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LOUDSPEAKERS, MICROPHONES, GRAMOPHONE PICK-UPS OR LIKE ACOUSTIC ELECTROMECHANICAL TRANSDUCERS; DEAF-AID SETS; PUBLIC ADDRESS SYSTEMS (generating mechanical vibrations in general B06B; transducers for measuring particular variables G01; transducers in clocks G04; producing sounds with frequency not determined by supply frequency G10K; transducers in recording or reproducing heads G11B; transducers in motors H02)
Definition statement
This subclass covers:
  • loudspeakers, microphones, acoustic transducers therefor producing acoustic waves or variations of electric current or voltage, or gramophone pick-ups
  • arrangements actuated by variations of electric current or voltage for cutting grooves in records;
  • circuits for the above-mentioned loudspeakers, microphones, acoustic transducers, gramophone pick-ups or arrangements;
  • monitoring or testing of the above-mentioned loudspeakers, microphones, acoustic transducers, gramophone pick-ups, arrangements or circuits therefor.
Relationship between large subject matter areas

Regarding producing sound, this subclass covers producing sound with a frequency determined by the frequency of the electrical signal applied to the transducer, whereas G10K covers producing sounds with frequency not so determined.

Informative references
Attention is drawn to the following places, which may be of interest for search:

Generating mechanical vibrations in general

Transducers for measuring particular variables

Transducers in recording or reproducing heads

Transducers in motors

Transmission systems employing ultrasonic, sonic or infrasonic waves

Special rules of classification within this subclass
  • Classification of invention information and additional information is obligatory.
  • Further detail not provided for in any of the main groups is provided for in the subgroups of Indexing Code groups H04R 2201/00 - H04R 2231/00, H04R 2307/00 and H04R 2400/00H04R 2499/00. These indexing code groups should be used in combination with CPC main trunk symbols to classify information highly relevant to the invention only. Classification is obligatory as indicated for each of the indexing groups concerned.
  • Of Indexing Code groups H04R 2201/00 - H04R 2231/00, H04R 2307/00 and H04R 2400/00 - H04R 2499/00 and of Indexing Code groups H04R 2201/02, H04R 2201/10 and H04R 2201/40 ONLY the subgroups should be used for classification.
  • Further detail not provided for in any of the main groups is provided for in the subgroups of Indexing Code groups H04S 2400/00 and H04S 2420/00 below. Classification is obligatory.
  • Modifications to the transducers itself (e.g. a Helmholtz resonator attached to a through-hole in the magnetic circuit or zeolytes attached to the frame) in order to modify the frequency response are to be classified in the appropriate place for the type of transducer (H04R 9/00 - H04R 23/00) as invention information in combination with H04R 1/22 as additional information.
Glossary of terms
In this subclass, the following terms (or expressions) are used with the meaning indicated:

Acoustic, Sound

cover the technical field dealing with ultrasonic, sonic or infrasonic waves

Deaf aid

hearing aid

Loudspeaker

transducer mounted in a casing for producing sound

Microphone

transducer mounted in a casing for collecting sound

Stereophonic system

two- or more channel system, e.g. quadraphonic, ambisonic or similar system

Transducer

a device that converts an electrical signal to an acoustic signal with a frequency which is determined by the frequency of the electrical signal applied to the transducer, or vice versa

Micro-structural device

1. micro-mechanical devices comprising movable, flexible or deformable elements; 2. three-dimensional structures without movable, flexible or deformable elements, comprising microformations designed to accomplish an essential structural function for interacting with their environment, as opposed to purely electronic or chemical functions, regardless of whether the structures are combined with micro-electronic devices or formed from specific materials;

Micro-structural system

1. systems of cooperating micro-structural devices; 2. micro-electro-mechanical or micro-opto-mechanical systems, which combine on a common substrate the specific features of micro-structural devices and electrical or optical components, e.g. for controlling, analysing or signalling the functioning of micro-structural devices.

Details of transducers, {loudspeakers or microphones}
Definition statement
This group covers:

Details of transducers, loudspeakers or microphones.

References relevant to classification in this group
This group does not cover:

Diaphragms for acoustic transducers

Details of transducers characterised by the nature of the transducer

Examples of places where the subject matter of this group is covered when specially adapted, used for a particular purpose, or incorporated in a larger system:

Mountings specially adapted for telephone equipment

Informative references
Attention is drawn to the following places, which may be of interest for search:

Mounting radio sets or communication systems in helmets

Special rules of classification within this group

Further detail is covered by the Indexing Code group H04R 2201/003 listed below. Classification is obligatory.

Glossary of terms
In this group, the following terms (or expressions) are used with the meaning indicated:

Casing

housing, cabinet, enclosure

Deaf aid

hearing aid, auditory prosthesis

Stereophonic system

two- or more channel system, e.g. quadraphonic, ambisonic or similar systems

{using digitally weighted transducing elements}
Definition statement
This subgroup covers:

Example for a loudspeaker transducer (the number of windings of the 15 coils ranges from 20-214)

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Example for a microphone transducer:

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Casings; Cabinets; {Supports therefor;} Mountings therein (H04R 1/28 takes precedence; {attachments for microphones H04R 1/08; mounting of transducers in earpieces H04R 1/1075})
Definition statement
This subgroup covers:

Casings, cabinets for transducers, their manufacture, their support, or mountings for transducers therein.

References relevant to classification in this group
This subgroup does not cover:

Mounting of transducers in earpieces

Attachments for microphones

Transducer mountings or enclosures modified by provision of mechanical or acoustic impedances, e.g. resonator, damping means

Informative references
Attention is drawn to the following places, which may be of interest for search:

Mounting of acoustic transducers in vehicles

Special rules of classification within this group

Further detail is covered by the subgroups of Indexing Code group H04R 2201/02 listed below. Classification is obligatory.

{Screens for loudspeakers}
Definition statement
This subgroup covers:

A mesh or grating covering the loudspeaker transducer or a sound path leading to the loudspeaker transducer

{Arrangements for fixing loudspeaker transducers, e.g. in a box, furniture}
Informative references
Attention is drawn to the following places, which may be of interest for search:

Furniture aspects of radio, television

Adaptations of chairs or stools for incorporating lamps, radio sets, bars, telephones, ventilation, heating or cooling arrangements or the like

{Supports for loudspeaker casings}
Definition statement
This subgroup covers:

Means to hold a loudspeaker casing for and during use

Informative references
Attention is drawn to the following places, which may be of interest for search:

Decoupling of vibrations by means of point-of-contact supports, e.g. ball bearings

Supports and stands in general

Structural association of microphone with electric circuitry therefor (in deaf-aid sets H04R 25/00)
Definition statement
This subgroup covers:

As shown in the figure circuitry (81) can be mounted inside the microphone (80)

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References relevant to classification in this group
This subgroup does not cover:

Structural association of microphone with electric circuitry therefor in deaf-aid sets

Informative references
Attention is drawn to the following places, which may be of interest for search:

MEMS packages

Micro-structural systems comprising a MEMS connected to control electronics, i.e. smart-MEMS

Packaging of Smart-MEMS, i.e. packaging together processing unit and MEMS

Arranging circuit leads; Relieving strain on circuit leads
Definition statement
This subgroup covers:

Connection or contacting arrangements specially adapted to transducers, loudspeakers or headphones.

In the example the tinsel wire 145 is prevented from contacting the diaphragm during vibration, by ring structure 150.

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In the example, the terminal 30 is prevented from bending too much during mounting, by stopper 29.

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Informative references
Attention is drawn to the following places, which may be of interest for search:

Means for relieving strain on wire connection, e.g. cord grip, for avoiding loosening of connections between wires and terminals within a coupling device terminating a cable or for flat or ribbon cables

Interconnections between the MEMS and external electrical signals

Connecting electric signal lines from the MEMS device with external electrical signal lines, e.g. through vias

Special rules of classification within this group

Further detail is covered by the subgroup of Indexing Code group H04R 2420/09 listed below. Classification is obligatory.

Mouthpieces; {Microphones;} Attachments therefor
Definition statement
This subgroup covers:

Microphones, mouthpieces or attachments therefor, e.g. spiders or microphone booms, or protective screens therefor, e.g. all weather or wind screens.

References relevant to classification in this group
This subgroup does not cover:

Throat mountings for microphones

Informative references
Attention is drawn to the following places, which may be of interest for search:

Supports and stands in general

Synonyms and Keywords

In patent documents, the expression/word “spider” is often used with the meaning “shock mount to elastically fasten microphones to stands”.

{Protective screens, e.g. all weather or wind screens}
Special rules of classification within this group

Further detail is covered by the subgroup of Indexing Code group.

Further detail is covered by Indexing Code group H04R 2410/07. Classification is obligatory.

Earpieces; Attachments therefor; {Earphones; Monophonic headphones (H04R 1/28 takes precedence; stereophonic headphones H04R 5/033)}
Definition statement
This subgroup covers:
  • Earphones or monophonic headphones;
  • Attachments therefor, e.g. ear hooks;
  • Details of headphones both of monophonic and stereophonic type, e.g. earpieces, e.g. intra-aural or supra-aural, or mechanical or electronic switches or control elements peculiar thereto, or accumulators or arrangements for charging peculiar thereto;
  • Assembly or manufacture thereof, e.g. ear pads;
  • Mechanical or electrical reduction of external noise.
References relevant to classification in this group
This subgroup does not cover:

Transducer mountings or enclosures modified by provision of mechanical or acoustic impedances, e.g. resonator, damping means

Example for the precedence rule:

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Earphone wherein the frequency response can be changed by changing (with slide 130) the number of holes (124) that are open/closed

Invention information: H04R 1/2826

Additional information: H04R 1/1016, H04R 1/1041

Informative references
Attention is drawn to the following places, which may be of interest for search:

Badges

Ornaments for ears

Earphones measuring physiological sounds (e.g. heart rate, breathing, pulse)

Transceivers carried on the body, e.g. in helmets

Sanitary or hygienic devices for earpieces

Special rules of classification within this group
  • When classifying in this group or in its subgroups, aspects relating to stereophonic headphones are to be classified in H04R 5/033 (additional information) as well.
  • Concerning inventions relating to hearing devices, if an application describes and shows the invention using only embodiments relating to ear- or headphones then H04R 1/10 or subgroups or H04R 5/033 or subgroups should be given as invention information. Dependent on the case, the mere statement that the invention is also applicable to hearing aids may render classification under H04R 25/00 useful, but only as additional information. Only if specific non-trivial embodiments for hearing aids are also shown, classification under H04R 25/00 as invention information may be considered as well.
{Earpieces of the intra-aural type}
Informative references
Attention is drawn to the following places, which may be of interest for search:

Earplugs for protection

Ear moulds for hearing aids

Special rules of classification within this group

Further detail is covered by the subgroups of Indexing Code group H04R 2460/09 and H04R 2460/11 listed below. Classification is obligatory.

{Accumulators or arrangements for charging (secondary cells per se H01M 10/00; charging in general H02J 7/00)}
Definition statement
This subgroup covers:

Adaptations to earpieces to enable charging.

For example:

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Informative references
Attention is drawn to the following places, which may be of interest for search:

Secondary cells per se

Charging in general

Battery chargers characterised by the mechanical construction, e.g. adapted for holding portable devices containing batteries

Aspects of accumulators, e.g. rechargeable batteries, fuel cells, in hearing aids

{Cables or cables storage, e.g. cable reels (cord reels per se H02G 11/02; arrangements for storing and repeatedly paying-out and re-storing lengths of conductors or cables B65H 75/34; extensible conductors or cables, e.g. self-coiling cords H01B 7/06)}
Definition statement
This subgroup covers:

For example:

A stereophonic earphone with two earpieces each with a cable (4,5). The cable is wound on a spool (8) for storing the cables when the earphone is not in use.

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For example:

A stereophonic headphone with a U-shaped slider (8) to adjust the length of the cable.

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Informative references
Attention is drawn to the following places, which may be of interest for search:

Arrangements for storing and repeatedly paying-out and re-storing lengths of conductors or cables

Extensible conductors or cables, e.g. self-coiling cords

Insulated conductors or cables characterised by their form with arrangements for facilitating mounting or securing

Cord reels per se

Protection of telephone cord; Guiding telephone cord; Winding-up telephone cord

{Mechanical or electronic switches, or control elements (switches in general H01H)}
Definition statement
This subgroup covers:

For example (electronic switch/control elements)

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For example (mechanical control element):

Earphone wherein the frequency response can be changed by changing (with slide 130) the number of holes (124) that are open/closed. Please take note of precedence rule referring to H04R 1/28.

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Informative references
Attention is drawn to the following places, which may be of interest for search:

Switches in general

Line cord switches

Hand-held casings specially adapted for remote control, e.g. of audio or video apparatus

Aspects relating to mechanical or electronic switches or control elements in hearing aids

{Earpiece supports, e.g. ear hooks (for stereophonic headphones H04R 5/0335)}
Definition statement
This subgroup covers:

For example:

Earpiece support 30 is used to attach headset to the ear. The arms 31 of support 30 are rotatable around hinge H.

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References relevant to classification in this group

Examples of places where the subject matter of this subgroup is covered when specially adapted, used for a particular purpose, or incorporated in a larger system:

Earpiece supports for stereophonic headphones

{Manufacture or assembly}
Definition statement
This subgroup covers:

Methods of manufacture or assembling as well as the way devices are assembled or constructed

For example:

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Informative references
Attention is drawn to the following places, which may be of interest for search:

Manufacture of mono- or stereophonic headphone parts not otherwise provided for in H04R, e.g. moulding of ear pads

{Constructional aspects of the interconnection between earpiece and earpiece support (earpiece support for monophonic headphones H04R 1/105; earpiece support for stereophonic headphones H04R 5/0335)}
Definition statement
This subgroup covers:

Example (ear hook):

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Example (headband):

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Example (headband):

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Informative references
Attention is drawn to the following places, which may be of interest for search:

Earpiece support for monophonic headphones

Earpiece support for stereophonic headphones

{Mountings of transducers in earphones or headphones}
Definition statement
This subgroup covers:

For example: (positioning of the transducers (4, 5, 6) in the earpiece)

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For example: (mounting of the loudspeakers mounted on the head support (in figure only the left side: left front 22L and left rear 24L both ported to the left ear)

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Informative references
Attention is drawn to the following places, which may be of interest for search:

Mounting transducers in general

{Reduction of ambient noise (active noise reduction per se G10K 11/175; protective devices for the ear, e.g. providing acoustic protection A61F 11/06)}
Definition statement
This subgroup covers:

For example:

A personal noise exposure dose meter integrated in an active hearing protective communications earplug, comprising a main section 1 containing two microphones an outer microphone M1 and an inner microphone M2, and a sound generator SG, which are used for active noise control. A sealing section 2 is attached to the main section. An acoustic transmission channel T1 connects microphone M2 to the inner portion of the meatus 3. Microphone M2 therefore picks up the sound present in the meatus 3, just outside the eardrum (tympanum) 4. An acoustic transmission channel T2 connects sound generator SG to the inner portion of the meatus 3. The sound generator SG may provide audible information to the user, in form of warning signals or synthetic speech.

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For example:

Noise reduction using feedback (23):

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Noise reduction using feedforward (33).

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Informative references
Attention is drawn to the following places, which may be of interest for search:

Protective devices for the ear, e.g. providing acoustic protection

Active noise reduction per se

Active noise control in general for microphones or earphones

Special rules of classification within this group

Further detail is covered by Indexing Code group H04R 2460/01. Classification is obligatory.

{Details not provided for in groups H04R 1/1008 - H04R 1/1083}
References relevant to classification in this group

Places in relation to which this group is residual:

Earpieces of the supra-aural or circum-aural type

Earpieces of the intra-aural type

Accumulators or arrangements for charging

Cables or cables storage, e.g. cable reels

Mechanical or electronic switches, or control elements

Earpiece supports, e.g. ear hooks

Manufacture or assembly

Reduction of ambient noise

Special rules of classification within this group
Sanitary or hygienic devices for mouthpieces or earpieces, e.g. for protecting against infection
Informative references
Attention is drawn to the following places, which may be of interest for search:

Hygienic or sanitary devices on telephone equipment

Mouthpieces in general

Earpieces in general

Ear wax barrier for hearing aids

Throat mountings for microphones
Informative references
Attention is drawn to the following places, which may be of interest for search:

Transceivers carried on the body, e.g. in helmets

Mouthpieces in general

Special adaptations for use as contact microphones

Arrangements for obtaining desired frequency or directional characteristics (for stereophonic purpose H04R 5/00)
References relevant to classification in this subclass/group
This subgroup does not cover:

Arrangements for obtaining desired frequency or directional characteristics for stereophonic purposes

Informative references
Attention is drawn to the following places, which may be of interest for search:

Speech enhancement by processing of the speech signal

for obtaining desired frequency characteristic only (circuit for combining transducers having different responses H04R 3/00 {for hearing aids H04R 25/407})
Definition statement
This subgroup covers:

Arrangements where the focus lies in the way the desired frequency characteristic is obtained

References relevant to classification in this subgroup

Examples of places where the subject matter of this group is covered when specially adapted, used for a particular purpose, or incorporated in a larger system:

Arrangements in hearing aids for obtaining desired frequency characteristic

Informative references
Attention is drawn to the following places, which may be of interest for search:

Circuits for combining transducers having different responses

Special rules of classification within this group

If a directivity effect is also addressed classification in H04R 1/32 or subgroups as additional information is required as well

Transducer mountings or enclosures modified by provision of mechanical or acoustic impedances, e.g. resonator, damping means {(combinations of transducers with horns, i.e. front-loaded horns H04R 1/30)}
Definition statement
This subgroup covers:

Transducer enclosure modified by provision of mechanical or acoustic impedances to achieve a desired frequency or phase response, e.g. enclosures:

  • of the bass reflex type,
  • of the bandpass type,
  • using passive membranes,
  • using acoustic labyrinths or transmission lines,
  • using back-loaded horns.
  • with adjustable volume
  • Virtual enlargement by e.g. zeolytes.

Transducer mountings or enclosures modified to reduce undesired resonances, i.e. standing waves within enclosure, or of vibrations, i.e. of the enclosure itself, by e.g.:

  • damping materials in the enclosure,
  • enclosure stiffening structures,
  • Helmholtz resonators,
  • special mountings of transducers.
References relevant to classification in this group
This subgroup does not cover:

Combinations of transducers with horns, i.e. front loaded horns

Examples of places where the subject matter of this group is covered when specially adapted, used for a particular purpose, or incorporated in a larger system:

Transducer mounting in telephone equipment improving the acoustic characteristics by means of constructional features of the housing, e.g. ribs, walls, resonating chambers or cavities.

Informative references
Attention is drawn to the following places, which may be of interest for search:

Mountings for loudspeaker in general

Mountings for microphones in general

Circuits for combining transducers having different responses

Special rules of classification within this group

Applications of the mountings or enclosures for loudspeaker transducers is to be classified in the appropriate subgroup with title "{for loudspeaker transducers}";

Further detail is covered by the subgroup of Indexing Code group H04R 2201/029. Classification is obligatory.

{for loudspeaker transducers}
Definition statement
This subgroup covers:

Example for porous material (12) for virtual volume increase, to improve bass response:

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Example for porous carbon material (20) for virtual volume increase, to improve bass response, membrane (22) is to prevent moisture from reaching the porous carbon material; membrane acoustically transparent)

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Special rules of classification within this group

The use of porous materials in loudspeaker enclosures for equivalent volume increase is classified under H04R 1/2803). For mid- and high-frequencies the porous material works as a damping material too. Thus classification in H04R 1/2876 or Indexing Code may be required if this aspect is addressed as well.

{Enclosures comprising vibrating or resonating arrangements (for the reduction of undesired resonances or vibrations H04R 1/2869)}
Definition statement
This subgroup covers:

Example (for H04R 1/2811): movable side wall (4) for varying volume to adapt frequency response:

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Example (for H04R 1/2811): left-hand figure amplified bass, and right-hand figure normal bass:

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{Vents, i.e. ports, e.g. shape thereof or tuning thereof with damping material (number or position of ports H04R 1/2815; vents in bandpass type enclosures H04R 1/2846)}
Definition statement
This subgroup covers:

Examples (for H04R 1/2826):

Vent with variable length:

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Shape of the vent:

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Shape and structure of the vent

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References relevant to classification in this group
This subgroup does not cover:

Number or position of ports in enclosures of the bass reflex type

Informative references
Attention is drawn to the following places, which may be of interest for search:

Vents in bandpass type enclosures

{using a passive diaphragm}
Special rules of classification within this group
  • Passive diaphragms or their suspension (invention) and being used in a bandpass type enclosure is classified in in H04R 1/283 or H04R 1/2834 (invention information), but H04R 1/2838 or H04R 1/2842 (additional information) is to be given as well;
  • Passive diaphragms or their suspension themselves are to be classified as diaphragms for transducers, i.e. in H04R 7/00 or H04R 31/003 (invention or additional information) where appropriate, but H04R 1/283 or H04R 1/2834 (additional information) is to be given as well.
Glossary of terms
In this subgroup, the following terms (or expressions) are used with the meaning indicated:

Passive diaphragm

Diaphragm driven by a fluid and providing an acoustic impedance

{of the bandpass type}
Definition statement
This subgroup covers:

For example (for H04R 1/2842):

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(vent 9 is not tuned to the wavelength)

Example 1st classification rule (the vent is replaced by a passive membrane):

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Example 2nd classification rule (vent replaced by tube tuned to the wavelength)

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Special rules of classification within this subclass/group
  • Bandpass type enclosures (invention) and using a passive membrane should be classified in H04R 1/2838 or H04R 1/2842 (invention information), but H04R 1/283 or H04R 1/2834 (additional information) is to be given as well.
  • Bandpass type enclosures (invention) and using an acoustic labyrinth of transmission line should be classified in H04R 1/2838 or H04R 1/2842 (invention information) but H04R 1/2853 or H04R 1/2857 (additional information) is to be given as well.
{Vents, i.e. ports, e.g. shape thereof or tuning thereof with damping material (number or position of ports H04R 1/2838; vents in bass reflex type enclosures H04R 1/2823)}
References relevant to classification in this group
This subgroup does not cover:

Number or position of ports in enclosures of the bandpass type

Informative references
Attention is drawn to the following places, which may be of interest for search:

Vents in bass reflex type enclosures

{using an acoustic labyrinth or a transmission line}
Definition statement
This subgroup covers:

Enclosures using an acoustic labyrinth or a transmission line. The acoustic labyrinth or the transmission line can be open or closed.

For example (for H04R 1/2857):

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The length of the top tubular part is tuned to the wavelength.

Special rules of classification within this group

Acoustic labyrinths or transmission lines (invention) and being used in a bandpass type enclosure is classified in H04R 1/2853 or H04R 1/2857 (invention information), but H04R 1/2838 or H04R 1/2842 (additional information) is to be given as well.

{using a back-loaded horn}
Definition statement
This subgroup covers:

Enclosures using a back-loaded horn. The horn has an aperture surface area that increases with distance from the transducer along the horn axis.

{Reduction of undesired resonances, i.e. standing waves within enclosure, or of undesired vibrations, i.e. of the enclosure itself}
Definition statement
This subgroup covers:

Reduction of undesired resonances not covered by its subgroups, e.g. by means of Helmholtz resonators

{by means of damping material, e.g. as cladding (damping material for tuning desired resonances H04R 1/2807, e.g. in vents H04R 1/2823, H04R 1/2846)}
References relevant to classification in this group
This subgroup does not cover:

The use of damping material to tune vents

The use of damping material to tune transmission lines

{by means of the enclosure structure, i.e. strengthening or shape of the enclosure (by means of Helmholtz resonators H04R 1/2869)}
Definition statement
This subgroup covers:

For example (for H04R 1/2888):

Stiffening panels inside the enclosure

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Shape of the enclosure to reduce reflexions within the enclosure

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References relevant to classification in this group
This subgroup does not cover:

Reduction of undesired resonances by means of Helmholtz resonators

{Mountings or supports for transducers}
Definition statement
This subgroup covers:

For example (for H04R 1/2896): DE202004017450U (rubber transducer mounting), US2005152570.

For example (for H04R 1/2896):

Rubber transducer mounting (5) combined with flexible cables (3):

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Elastic mounting (20) with dampening buffer element (30)

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Combinations of transducers with horns, e.g. with mechanical matching means {, i.e. front-loaded horns} (horns in general G10K; {transducer enclosures or mountings using a back-loaded horn H04R 1/2861; application of horns as guiding means to obtain a predetermined directivity characteristic H04R 1/345})
Definition statement
This subgroup covers:

Combinations of transducers with front-loaded horns; Enclosures using front-loaded horns, the acoustic horns predominantly being characterised by the mechanical matching, even though a directivity effect is also present

The horn has an aperture surface area that increases with distance from the transducer along the horn axis

For example:

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In the example shown on the left the exponential area increase is obtained by the combination of a cylindrical housing (1) with a flat sloped plate (3).

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Informative references
Attention is drawn to the following places, which may be of interest for search:

Horn in general

Transducer enclosures or mountings using a back-loaded horn

Application of horns as guiding means to obtain a predetermined directivity characteristic

Special rules of classification within this group

Further detail is covered by the subgroup of Indexing Code group H04R 2400/13 listed below. Classification is obligatory.

for obtaining desired directional characteristic only {(specially adapted for hearing aids H04R 25/40)}
Definition statement
This subgroup covers:

Arrangements where the focus lies in the way the desired directional characteristic is obtained

References relevant to classification in this group

Examples of places where the subject matter of this main group is covered when specially adapted, used for a particular purpose, or incorporated in a larger system:

Arrangements in hearing aids for obtaining desired directional characteristic

Informative references
Attention is drawn to the following places, which may be of interest for search:

Mounting transducers, e.g. provided with mechanical moving or orienting device

Special rules of classification within this group
  • If a frequency effect is also addressed classification in H04R 1/22 or subgroups as additional information is required as well
  • Further detail is covered by Indexing Code group H04R 2410/01. Classification is obligatory.
by using a single transducer with sound reflecting, diffracting, directing or guiding means {(specially adapted for hearing aids H04R 25/402)}
Definition statement
This subgroup covers:

Sound reflecting, diffracting, directing or guiding means, e.g. horns to obtain a desired directivity characteristic, acoustic lenses, tubes, or phase plugs

References relevant to classification in this group

Examples of places where the subject matter of this main group is covered when specially adapted, used for a particular purpose, or incorporated in a larger system:

Arrangements specially adapted for hearing aids

{for loudspeakers}
Definition statement
This subgroup covers:

For example: (horn (top figure) used to obtain predetermined directivity (lower figures)

media44.png

For example: (plurality of plates (210) functioning as an acoustic lens).

media47.png

Informative references
Attention is drawn to the following places, which may be of interest for search:

Methods or devices for sound-focusing or directing

Horn-loaded compression drivers and impedance frequency matching

Single aperture acoustic lenses

Special rules of classification within this group

Further detail is covered by Indexing Code group H04R 2201/34 listed below. Classification is obligatory.

{for obtaining a phase-shift between the front and back acoustic wave}
Definition statement
This subgroup covers:

For example:

media48.png

by using a single aperture of dimensions not greater than the shortest operating wavelength
Definition statement
This subgroup covers:

Such an aperture functions as an acoustic lens

Informative references
Attention is drawn to the following places, which may be of interest for search:

Other types of acoustic lenses

by combining a number of identical transducers {(specially adapted for hearing aids H04R 25/405)}
References relevant to classification in this group
This subgroup does not cover:

Combining a number of identical transducers for stereophonic purpose

Examples of places where the subject matter of this main group is covered when specially adapted, used for a particular purpose, or incorporated in a larger system:

Combining a number of identical transducers specially adapted for hearing aids

Informative references
Attention is drawn to the following places, which may be of interest for search:

Constructional aspects of beam steering

Sound-focusing or directing using electrical steering of transducer arrays, e.g. beam steering

Special rules of classification within this group

Further detail is covered by the subgroups of Indexing Code group H04R 2201/40. Classification is obligatory.

{loud-speakers}
Informative references
Attention is drawn to the following places, which may be of interest for search:

Circuits for distributing signals of two or more loudspeakers

{microphones}
Informative references
Attention is drawn to the following places, which may be of interest for search:

Circuits for combining the signals of two or more microphones

Special rules of classification within this group

Further detail is covered by the subgroup of Indexing Code group H04R 2410/05. Classification is obligatory.

Special adaptations for use as contact microphones, e.g. on musical instrument, on stethoscope (throat mountings H04R 1/14)
References relevant to classification in this subclass/group
This subgroup does not cover:

Throat mountings for microphones

Circuits for transducers {, loudspeakers or microphones}
Definition statement
This group covers:

Circuits for transducers, e.g.:

  • Damping motional feedback circuits.
  • Circuits for combining the signals of two or more microphones.
  • Protection circuits for transducers.
  • Circuits for preventing acoustic reaction.
  • Circuits for distributing a signal to a plurality of loudspeakers.
  • Circuits for correcting the frequency response of transducers.
References relevant to classification in this group
This group does not cover:

Arrangements for producing a reverberation or echo sound

Amplifiers

Testing of transducer, loudspeaker or microphone connection for non-stereophonic purposes

Examples of places where the subject matter of this group is covered when specially adapted, used for a particular purpose, or incorporated in a larger system:

Circuits for stereophonic arrangements

Circuits for combining the signals of two or more microphones or loudspeakers specially adapted for hearing aids

Public address systems, e.g. circuits therefor

Stereophonic systems

Informative references
Attention is drawn to the following places, which may be of interest for search:

Driving circuits for generating mechanical vibrations of infrasonic, sonic, or ultrasonic frequency (specially adapted for particular applications, see the relevant subclass)

Audio-frequency transformers or mutual inductances, i.e. not suitable for handling frequencies considerably beyond the audio range

Low frequency amplifiers, e.g. audio preamplifiers

Power amplifiers using a combination of several semiconductor amplifiers

Combinations of amplifiers using coupling networks with distributed constants

Combinations of amplifiers, e.g. multi-channel amplifiers for stereophonics

Control of amplification

Remote control of amplification, tone, or bandwidth

Arrangements for preventing acoustic feedback

Two-way loud-speaking telephone systems with means for conditioning the signal, e.g. for suppressing echoes for one or both directions of traffic

Special rules of classification within this group

Further detail is covered by the subgroups of Indexing Code groups H04R 2201/401, H04R 2201/403, H04R 2201/405, H04R 2203/12, H04R 2410/07, H04R 2420/01, H04R 2420/03, H04R 2420/05, H04R 2430/01 and H04R 2430/03. Classification is obligatory.

Glossary of terms
In this group, the following terms (or expressions) are used with the meaning indicated:

Deaf aid

hearing aid, auditory prosthesis

Stereophonic system

two- or more channel system, e.g. quadraphonic, ambisonic or similar systems

{for combining the signals of two or more microphones (specially adapted for hearing aids H04R 25/407)}
References relevant to classification in this group

Examples of places where the subject matter of this group is covered when specially adapted, used for a particular purpose, or incorporated in a larger system:

Circuits for combining the signals of two or more microphones to obtain desired directional characteristics specially adapted for hearing aids

Circuits for combining the signals of two or more microphones, i.e. mixing, specially adapted for hearing aids

Informative references
Attention is drawn to the following places, which may be of interest for search:

Spatial or constructional stereophonic arrangement of microphones

Combining a number of identical transducers

H04R 1/40 and the subgroups of H04R 2201/40

Direction-finders for determining the direction from which infrasonic, sonic, ultrasonic, not having a directional significance, are being received

Systems for determining distance or velocity not using reflection or re-radiation and using ultrasonic, sonic, or infrasonic waves

Circuits for sound-focusing or directing using electrical steering of transducer arrays, e.g. beam steering

Speech recognition techniques specially adapted for robustness in adverse environments

Combining signals of a signal microphone and a noise microphone for speech processing

Beamforming for speech processing

Telephonic conference arrangements

Video conference systems

Special rules of classification within this group

Further detail is covered by Indexing Code groups H04R 2410/01, H04R 2410/05 and H04R 2430/20 and its subgroups. Classification is obligatory.

for preventing acoustic reaction {, i.e. acoustic oscillatory feedback (specially adapted for hearing aids H04R 25/453)}
References relevant to classification in this group

Examples of places where the subject matter of this main group is covered when specially adapted, used for a particular purpose, or incorporated in a larger system:

Electronic prevention acoustic reaction specially adapted for hearing aids

Informative references
Attention is drawn to the following places, which may be of interest for search:

Mechanical acoustic echo cancellation for telephony

Electronic acoustic echo cancellation for telephony

for correcting frequency response
Informative references
Attention is drawn to the following places, which may be of interest for search:

Tone control or bandwidth control in amplifiers

Synergistic effects of band splitting and sub-band processing

for distributing signals to two or more loudspeakers {(specially adapted for hearing aids H04R 25/407)}
References relevant to classification in this group

Examples of places where the subject matter of this main group is covered when specially adapted, used for a particular purpose, or incorporated in a larger system:

Circuits for combining the signals of two or more loudspeakers to obtain a desired directivity characteristic specially adapted for hearing aids

Public address systems

Informative references
Attention is drawn to the following places, which may be of interest for search:

Directing sound using electrical steering of transducer arrays, e.g. beam steering

Special rules of classification within this group

Further detail is covered by Indexing Code groups H04R 2203/12 and H04R 2430/20. Classification is obligatory.

Stereophonic arrangements (stereophonic pick-ups H04R 9/16, H04R 11/12, H04R 17/08, H04R 19/10)
Definition statement
This group covers:

Spatial or constructional arrangements of loudspeakers or of electro-acoustic devices for stereophonic purposes or specific circuit arrangements therefor, e.g.

  • aspects relating to docking-station type assemblies to obtain an acoustical effect,
  • positioning of loudspeakers for spatial sound reproduction,
  • plurality of transducers corresponding to a plurality of sound channels in each earpiece of headphones or in a single enclosure,
  • single (sub)woofer with two or more satellite loudspeakers for higher frequency band reproduction driven via the (sub)woofer,
  • sound field microphones, or
  • dummy heads
References relevant to classification in this group
This group does not cover:

Stereophonic pick-ups, i.e. wherein signals are recorded or played back by vibration of a stylus in two orthogonal directions simultaneously

Glossary of terms
In this group, the following terms (or expressions) are used with the meaning indicated:

Stereophonic system

two- or more channel system, e.g. quadraphonic, ambisonic or similar systems

Spatial or constructional arrangements of loudspeakers
Definition statement
This subgroup covers:

Spatial or constructional arrangements of loudspeakers or loudspeaker transducers for stereophonic reproduction, e.g.

  • aspects relating to docking-station type assemblies to obtain an acoustical effect,
  • positioning of loudspeakers for spatial sound reproduction,
  • plurality of transducers corresponding to a plurality of sound channels in each earpiece of headphones or in a single enclosure, or
  • single (sub)woofer with two or more satellite loudspeakers for higher frequency band reproduction driven via the (sub)woofer.
Informative references
Attention is drawn to the following places, which may be of interest for search:

Mounting radio sets or communication systems in helmets

Mounting of acoustic transducers in vehicles

Special rules of classification within this group

Further detail is covered by Indexing Code groups H04R 2205/021, H04R 2205/022, H04R 2205/024 and H04R 2205/026. Classification is obligatory.

Spatial or constructional arrangements of microphones, e.g. in dummy heads
Definition statement
This subgroup covers:

Spatial or constructional arrangements of microphones or microphone transducers for stereophonic sound capture.

For example (dummy head):

media49.png

media50.png

For example (sound field microphone):

media51.png

Informative references
Attention is drawn to the following places, which may be of interest for search:

Arrangements for obtaining desired frequency or directional characteristics by combining a number of identical transducers microphones

Circuits for combining the signals of two or more microphones for non-stereophonic purposes

Hearing aid circuits for combining signals of transducers

Binaural hearing aids

Details of transducer arrays

Headphones for stereophonic communication {(details thereof, e.g. relating to batteries, cables or control elements H04R 1/10)}
References relevant to classification in this group
This subgroup does not cover:

Details thereof, e.g. relating to batteries, cables or control elements

Transceivers carried on the body, e.g. in helmets

Sound field enhancement in stereophonic headphones

Special rules of classification within this group
  • Concerning inventions relating to hearing devices, if an application describes and shows the invention using only embodiments relating to ear- or headphones then H04R 1/10 or subgroups or H04R 5/033 or subgroups should be given as invention information. Dependent on the case, the mere statement that the invention is also applicable to hearing aids may render classification under H04R 25/00 useful, but only as additional information. Only if specific non-trivial embodiments for hearing aids are also shown, classification under H04R 25/00 as invention information may be considered as well.
  • Further detail is covered by the subgroups of Indexing Code groups H04R 2201/103, H04R 2201/105, H04R 2420/09 and H04R 2460/03. Classification is obligatory.
{Earpiece support, e.g. headbands or neckrests (for monophonic headphones H04R 1/105)}
Definition statement
This subgroup covers:

For example: segmented headband for easy storage of the headphone

media53.png

For example: (head support with loudspeakers mounted thereon (in figure only the left side: left front speaker 22L and left rear speaker 24L both ported to the left ear)

media16.png

Informative references
Attention is drawn to the following places, which may be of interest for search:

Earpiece support for monophonic headphones, e.g. earhooks

Circuit arrangements, {e.g. for selective connection of amplifier inputs/outputs to loudspeakers, for loudspeaker detection, or for adaptation of settings to personal preferences or hearing impairments (combinations of amplifiers H03F 3/68; stereophonic systems H04S)}
References relevant to classification in this group

Examples of places where the subject matter of this group is covered when specially adapted, used for a particular purpose, or incorporated in a larger system:

Circuits or components specially adapted for stereophonic broadcast systems

Broadcast systems for the distribution of stereophonic information

Circuits or components specially adapted for stereophonic broadcast receiving

Stereophonic systems

Informative references
Attention is drawn to the following places, which may be of interest for search:

Amplifiers

Low frequency amplifiers, e.g. audio preamplifiers

Power amplifiers using a combination of several semiconductor amplifiers

Combinations of amplifiers using coupling networks with distributed constants

Combinations of amplifiers, e.g. multi-channel amplifiers for stereophonics

Control of amplification

Remote control of amplification, tone, or bandwidth

Transmission systems for stereophonic reception

Powerline communication in general

Audio/video applications of powerline communications

Testing of transducer, loudspeaker or microphone connection for non-stereophonic purposes

Special rules of classification within this group

Further detail is covered by Indexing Code groups H04R 2205/041, subgroups of H04R 2420/00, and H04R 2430/01. Classification is obligatory.

Diaphragms for electromechanical transducers (in general F16J 3/00); Cones (for musical instruments G10 ){(cones, diaphragms or the like, for emitting or receiving sound in general G10K 13/00; Mounting thereof)}
Definition statement
This group covers:
  • Diaphragms for electromechanical transducers.
  • Cones
  • Mountings thereof, e.g. outer suspension.
Informative references
Attention is drawn to the following places, which may be of interest for search:

MEMS structures allowing for movement

Type of movement

Diaphragms in general

Pressure measurement / constructional details associated with semiconductive diaphragm sensors, e.g. etching of diaphragms

Cones, diaphragms or the like, for emitting or receiving sound in general

Apparatus or processes specially adapted for the manufacture of diaphragms or surrounds for transducers

characterised by the construction
Special rules of classification within this group

Further detail is covered by Indexing Code groups H04R 2207/021, H04R 2231/001, H04R 2231/003 and H04R 2307/021 - H04R 2307/029. Classification is obligatory.

Plane diaphragms
Informative references
Attention is drawn to the following places, which may be of interest for search:

In vehicles

Projection screens allowing free passage of sound

Special rules of classification within this group

Further detail is covered by Indexing Code groups H04R 2440/01 and H04R 2440/07. Classification is obligatory.

{using the distributed mode principle, i.e. whereby the acoustic radiation is emanated from uniformly distributed free bending wave vibration induced in a stiff panel and not from pistonic motion}
Definition statement
This subgroup covers:

For example: Upon excitation of diaphragm 1 by piezoelectric exciter 15 the diaphragm generating bending wave in itself and eventually produces sound by resonating.

media55.png

media56.png

Informative references
Attention is drawn to the following places, which may be of interest for search:

Touch screens using propagation of acoustic waves

Using non-resonant travelling waves

Special rules of classification within this group

Further detail is covered by Indexing Code groups H04R 2440/03 and H04R 2440/05. Classification is obligatory.

{dome-shaped}
Definition statement
This subgroup covers:

For example: (dome 52).

media60.png

corrugated, pleated or ribbed
Definition statement
This subgroup covers:

For example: DE202007016414 (air motion transformer).

For example: ribs to provide rigidity to the central part of the loudspeaker diaphragm

media61.png

For example: air motion transformer (AMT) with a meander shaped diaphragm and air pockets (6). Upon energising the transformer (current through conductors 2) and due to the magnetic field perpendicular to the current, the air in the pockets is pushed out or pulled in, thus producing sound.

media62.png

Mounting or tensioning of diaphragms or cones
Definition statement
This subgroup covers:

For example: diaphragm is mounted to the frame (26) by surround (29) which is connected to the membrane (27) within its periphery (at 200)

media63.png

at the periphery
Definition statement
This subgroup covers:

For example: membrane (2) is extended to form outer suspension (21), whose elastic properties are adapted by the elastic layer (22).

media64.png

For example: membrane (34) divided in a suspension part (34A, 34B) and a central sound producing part (34C)

media65.png

Informative references
Attention is drawn to the following places, which may be of interest for search:

Manufacture of surrounds

Securing diaphragm or cone resiliently to support by flexible material, springs, cords, or strands
Definition statement
This subgroup covers:

For example:

media66.png

Special rules of classification within this group

Further detail is covered by Indexing Code groups H04R 2231/001, H04R 2231/003, H04R 2307/201 - H04R 2307/207. Classification is obligatory.

Clamping rim of diaphragm or cone against seating
Definition statement
This subgroup covers:

For example: Microphone comprising a vibrating plate (12) with polar ring which is clamped via a spacer (13) between base (14, 16) and the casing (102). Groove 102h is formed to prevent deformation of the polar ring which would negatively affect the acoustic properties membrane (2) is extended to form outer suspension (21), whose elastic properties are adapted by the elastic layer (22).

media67.png

Tensioning by means acting directly on free portions of diaphragm or cone
Definition statement
This subgroup covers:

For example: EP0330423.

For example: tensioning by springs 5’

media68.png

Damping by means acting directly on free portion of diaphragm or cone (air damping H04R 1/28)
Definition statement
This subgroup covers:

For example: damping by elastic material 27

media70.png

media71.png

For example: sound producing diaphragm provided with a damping layer (12) to dampen vibration in the diaphragm

media72.png

Informative references
Attention is drawn to the following places, which may be of interest for search:

Transducer mountings or enclosures providing mechanical or acoustic impedances by air damping

Transducers of moving-coil, moving-strip, or moving-wire type
Definition statement
This group covers:

Transducers of moving-coil, moving-strip, or moving-wire type, e.g.

  • general constructional aspects thereof
  • cooling aspects;
  • constructional aspects of the magnetic circuit, e.g. to reduce eddy currents or stray flux;
  • aspects of the voice coil, i.e. mounting, construction or centring thereof
Informative references
Attention is drawn to the following places, which may be of interest for search:

Generating mechanical vibrations of infrasonic, sonic, or ultrasonic frequency operating with electromagnetism, e.g. using vibrating magnet, armature or coil system

Dynamo-electric motors with vibrating magnet, armature or coil system

Special rules of classification within this group

Further detail is covered by Indexing Code group H04R 2201/003 and the subgroups of Indexing Code group H04R 2440/00. Classification is obligatory.

Details
Definition statement
This subgroup covers:
  • General constructional aspects of the transducers;
  • Cooling aspects;
  • Constructional aspects of the magnetic circuit, e.g. to reduce eddy currents or stray flux;
  • Aspects of the voice coil, i.e. mounting, construction or centring thereof.
Special rules of classification within this group

Further detail is covered by Indexing Code groups H04R 2209/021 - H04R 2209/027 and the subgroups of Indexing Code group H04R 2400/00. Classification is obligatory.

{Magnetic circuit}
Informative references
Attention is drawn to the following places, which may be of interest for search:

Manufacturing aspects of the magnetic circuit of loudspeaker or microphone transducers

{Air gaps using a magnetic fluid}
Informative references
Attention is drawn to the following places, which may be of interest for search:

Magnetic liquids in general, e.g. ferrofluids

Construction, mounting, or centering of coil
Special rules of classification within this group

Further detail is covered by the subgroups of Indexing Code groups H04R 2209/041 and H04R 2209/043 listed below. Classification is obligatory.

{Inner suspension or damper, e.g. spider (outer suspension or surround H04R 7/16)}
Definition statement
This subgroup covers:

For example: the inner suspension (13) is formed with leg portions (13b, 13c) having equal length, to prevent lateral vibration of the bobbin (8). Thus excursion of suspension and thus of the diaphragm can be increase without increasing the diameter of the inner suspension.

media73.png

Informative references
Attention is drawn to the following places, which may be of interest for search:

Outer suspension or surround

Glossary of terms
In this subgroup, the following terms (or expressions) are used with the meaning indicated:

spider

inner suspension usually placed between voice coil former and frame, for providing a restoring force enabling the return of the transducer membrane to its normal resting position and for centring the voice coil

{Mounting (H04R 9/043 takes precedence)}
Definition statement
This subgroup covers:

Mounting of the voice coil or the bobbin on which the voice coil is wound

For example: the connection between bobbin (8) and diaphragm (2) is provided with a groove, which is filled with glue to strengthen the connection.

media74.png

Example: bobbin assembly (355) removably mounted to the inner circumference of the diaphragm (310). Thus replacement of damaged assembly requires minimal effort.

media75.png

Example: bobbin (140) is mounted at its top directly to outer suspension and in the middle via bridge (160). Thus the bobbin is prevented from bending.

media76.png

Informative references
Attention is drawn to the following places, which may be of interest for search:

Inner suspension or damper

{Construction}
Definition statement
This subgroup covers:
  • Constructional aspects of the voice coil, e.g. shape of the coil, the winding angle, shape or material of the windings,
  • Constructional aspects of the bobbin on which a voice coil is to be wound, e.g. material, shape, connection with voice coil
Informative references
Attention is drawn to the following places, which may be of interest for search:

Coils per se and their manufacture

Loudspeakers
Definition statement
This subgroup covers:
  • Transducers for loudspeakers of the pistonic type, e.g. compression drivers, or of the distributed mode type;
  • Inertial transducers, i.e. transducers for loudspeakers wherein the voice coil is directly mounted to vibrating diaphragm and the magnetic circuit is floating but suspended with respect to the diaphragm and voice coil.
Informative references
Attention is drawn to the following places, which may be of interest for search:

Telephone receivers

Special rules of classification within this group

Further detail is covered by Indexing Code group and by H04R 2400/13. Classification is obligatory.

{using the principle of inertia}
Definition statement
This subgroup covers:

Transducers for loudspeakers wherein the voice coil is directly mounted to vibrating diaphragm and the magnetic circuit is floating but suspended with respect to the diaphragm and voice coil.

For example: body sensed speaker, that can be placed in e.g. waistcoats, cushions, matrasses, belts

media248.png

For example: exciter for distributed mode loudspeakers (DML)

media78.png

Informative references
Attention is drawn to the following places, which may be of interest for search:

Transducers of moving-armature or moving-core type

Special rules of classification within this group

Further detail is covered by Indexing Code group H04R 2400/07. Classification is obligatory.

Microphones
Informative references
Attention is drawn to the following places, which may be of interest for search:

Transducers having separately controllable opposing diaphragms, e.g. for ring-tone and voice, or for combined microphone/-receiver in telephones

Transducers used as a loudspeaker to generate sound as well as a microphone to detect sound

Telephone receivers
Informative references
Attention is drawn to the following places, which may be of interest for search:

Generating mechanical vibrations of infrasonic, sonic, or ultrasonic frequency using vibrating magnet, armature or coil system

Generating vibrations with systems involving rotary unbalanced masses

Tactile signalling systems

Transducers having separately controllable opposing diaphragms, e.g. for ring-tone and voice

Transducers used as a loudspeaker to generate sound as well as a microphone to detect sound

Transducers capable of generating both sound as well as tactile vibration e.g. as used in cellular phones

Transducers of moving-armature or moving-core type (acoustic diaphragm of magnetisable material directly coacting with electromagnet H04R 13/00)
Informative references
Attention is drawn to the following places, which may be of interest for search:

Generating mechanical vibrations of infrasonic, sonic, or ultrasonic frequency operating with electromagnetism, e.g. using vibrating magnet, armature or coil system

Dynamo-electric motors with vibrating magnet, armature or coil system

Transducers of moving-coil, moving-strip, or moving-wire type

Loudspeaker transducers using the principle of inertia

Acoustic diaphragm of magnetisable material directly co-acting with electromagnet

Special rules of classification within this group

Further detail is covered by the subgroups of Indexing Code groups H04R 2400/01, H04R 2400/03, and H04R 2440/01 - H04R 2440/07.

Loudspeakers
Definition statement
This subgroup covers:

For example:

The voice coil (2) is static. Upon energising the magnets (4-6) move.

media79.png

Example of a hearing aid receiver:

Armature 136 has a fixed (146) and a movable arm (144). When coils 134 is energised, movable arm 144 moves and drives membrane (118) via a linkage 138, thus producing sound.

media80.png

Example of a bone conduction speaker:

media81.png

Voice coil 30 is mounted directly to base plate 14 which is part of the transducer frame. The magnetic circuit (yoke 22, magnet 24, base plate 26) is movably attached to the frame 12 via damper 20, such that upon energising the voice coil the armature moves.

References relevant to classification in this group
This subgroup does not cover:

Telephone receivers of the moving-armature or moving-core type

Special rules of classification within this group

Further detail is covered by Indexing Code group H04R 2400/07 and H04R 2400/11. Classification is obligatory.

Telephone receivers
Informative references
Attention is drawn to the following places, which may be of interest for search:

Generating vibrations with systems involving rotary unbalanced masses

Tactile signalling systems

Transducers having separately controllable opposing diaphragms, e.g. for ring-tone and voice

Transducers used as a loudspeaker to generate sound as well as a microphone to detect sound

Transducers capable of generating both sound as well as tactile vibration e.g. as used in cellular phones

Transducers having an acoustic diaphragm of magnetisable material directly co-acting with electromagnet
Definition statement
This group covers:

Transducers for loudspeakers or microphones, in which the membrane is part of the magnetic circuit.

For example:

media82.png

Special rules of classification within this group

Further detail is covered by the subgroup of Indexing Code group H04R 2400/11 listed below. Classification is obligatory.

Magnetostrictive transducers (magnetostrictive elements in general H01L 41/00)
Definition statement
This group covers:

In the example shown in the figure below a configuration of the magnetostrictive actuator 103 is presented. The magnetostrictive actuator 103 has a rod-like magnetostrictive element 151 that is displaced along its extension direction, a solenoid coil 152 for generating a magnetic field, which is positioned around this magnetostrictive element 151, a driving rod 103a as driving member, which is connected to an end of the magnetostrictive element 151 and transmits any displacement output of the magnetostrictive actuator 103, and a container 154 that contains the magnetostrictive element 151 and the solenoid coil 152 therein.

media83.png

Informative references
Attention is drawn to the following places, which may be of interest for search:

Magnetostrictive elements in general

Details of magnetostrictive devices

Materials; Manufacture of magnetostrictive devices

Special rules of classification within this group

Further detail is covered by Indexing Code group H04R 2201/003, H04R 2217/01, H04R 2400/03 and H04R 2400/11. Classification is obligatory.

Piezo-electric transducers; Electrostrictive transducers (piezo-electric or electrostrictive elements in general H01L 41/00; details of piezo-electric or electrostrictive motors, generators or positioners {H01L 41/00})
Informative references
Attention is drawn to the following places, which may be of interest for search:

Piezo-electric or electrostrictive elements in general

Details of piezo-electric or electrostrictive motors, generators or positioners

Details of piezo-electric or electrostrictive devices

Selection of materials for piezo-electric or electrostrictive devices

Manufacture of piezo-electric or electrostrictive devices

Details of piezo-electric or electrostrictive motors, generators or positioners

Special rules of classification within this group

Further detail is covered by Indexing Code group H04R 2201/003, H04R 2217/01, H04R 2400/03, H04R 2400/11 and the subgroups of Indexing Code group H04R 2440/00. Classification is obligatory.

{using a piezo-electric polymer}
Informative references
Attention is drawn to the following places, which may be of interest for search:

Piezo-electric or electrostrictive devices of macromolecular compositions

Microphones
Informative references
Attention is drawn to the following places, which may be of interest for search:

Piezo-electric or electrostrictive devices with mechanical input and electrical output

Special rules of classification within this group

Further detail is covered by Indexing Code group H04R 2410/03. Classification is obligatory.

{using a piezo-electric polymer}
Informative references
Attention is drawn to the following places, which may be of interest for search:

Piezo-electric or electrostrictive devices of macromolecular compositions

Electrostatic transducers
Informative references
Attention is drawn to the following places, which may be of interest for search:

Generating mechanical vibrations of infrasonic, sonic, or ultrasonic frequency using electrostatic transducers, e.g. electret-type

Special rules of classification within this group

Further detail is covered by Indexing Code groups H04R 2400/11 and H04R 2410/03. Classification is obligatory.

{using semiconductor materials}
Informative references
Attention is drawn to the following places, which may be of interest for search:

Transducers other than those covered by groups H04R 9/00 - H04R 21/00 using solid state devices

Arrangements for avoiding sticking of the flexible or moving parts of MEMS devices having such parts

MEMS packages and encapsulations

Microphones and microspeakers

MEMS structures allowing for movement

Type of movement

Pressure measurement / constructional details associated with semiconductive diaphragm sensors, e.g. etching of diaphragms

Loudspeakers (H04R 19/01 takes precedence)
References relevant to classification in this subclass/group
This subgroup does not cover:

Electrostatic transducers characterised by the use of electrets

for loudspeakers

Microphones (H04R 19/01 takes precedence)
References relevant to classification in this subclass/group
This subgroup does not cover:

Electrostatic transducers characterised by the use of electrets

for microphones

Variable-resistance transducers (gaseous resistance transducers H04R 23/00; magneto-resistive transducers H04R 23/00)
References relevant to classification in this group
This group does not cover:

Gaseous resistance transducers

Magneto resistive transducers

Transducers other than those covered by groups H04R 9/00 - H04R 21/00 {(diaphragms for transducers of the distributed-mode type H04R 7/045)}
References relevant to classification in this group

Places in relation to which this group is residual:

Transducers of moving-coil, moving-strip or moving-wire type

Transducers of moving-armature or moving-core type

Transducers having an acoustic diaphragm of magnetisable material directly co-acting with electromagnet

Magnetostrictive transducers

Piezo-electric transducers; Electrostrictive transducers

Electrostatic transducers

Variable-resistance transducers

Informative references
Attention is drawn to the following places, which may be of interest for search:

Diaphragms for transducers of the distributed-mode type

{using ionised gas}
Informative references
Attention is drawn to the following places, which may be of interest for search:

Sound producing devices using optical excitation, e.g. laser bundle

Sound producing devices using electric discharge

{using solid state devices (solid state devices per se H01L)}
Definition statement
This subgroup covers:

Acoustic transducers using solid state devices and not covered by H04R 9/00 - H04R 21/00

References relevant to classification in this subclass/group
This subgroup does not cover:

Electrostatic transducers using semiconductor materials

Informative references
Attention is drawn to the following places, which may be of interest for search:

Solid state devices per se

Deaf-aid sets {providing an auditory perception; Electric tinnitus maskers providing an auditory perception} (constructions of transducers per se H04R 9/00 - H04R 23/00; {non-electric hearing aids A61F 11/008; replacing direct auditory perception by another kind of perception A61F 11/04; electrical stimulation of auditory nerves to promote the auditory function A61N 1/36032} ; structural combination with spectacle frames G02C 11/06; processing of speech signals G10L 21/00)
Definition statement
This group covers:
  • Electric hearing aids acting indirectly, e.g. acoustically, or directly on the ear drum, mastoid, ossicles or cochlea and providing an auditory perception
  • Electric tinnitus maskers providing an auditory perception
  • Electrical or mechanical aspects thereof, e.g.
  • signal processing, e.g. beamforming, prevention of acoustic reaction or noise reduction,
  • electronic fitting, i.e. initial adaptation, e.g. by a hearing aid acoustitian, or subsequent adaptation of hearing aid parameters, e.g. in dependence of listening situation
  • testing or monitoring
  • wired or wireless external connection or remote control
  • manufacture or assembly, e.g. mounting of transducers or of the batteries
  • ear tips, ear moulds or there manufacture
  • WARNING:
  • Groups H04R 25/30 - H04R 25/75 do not correspond to former or current IPC groups.
  • Concordance CPC : IPC for these groups is as follows:
References relevant to classification in this group
This group does not cover:

Electrical stimulation of auditory nerves to promote the auditory function, e.g. cochlear implants

Informative references
Attention is drawn to the following places, which may be of interest for search:

Constructions of transducers per se

Amplifying systems for the deaf

Monitoring arrangements; Testing arrangements in general

Ornaments for ears

Earphones measuring physiological sounds, e.g. heartrate, breathing, pulse

Non-electric hearing aids

Replacing direct auditory perception by another kind of perception

Structural combination of hearing aids with spectacle frames

Teaching or communicating with deaf persons

Directing sound using electrical steering of transducer arrays, e.g. beam steering

Coding or decoding of speech or audio signal, using source filter models or psychoacoustic analysis

Processing of speech signals

Automatic gain control in audio amplifiers

Telephone sets for the hearing impaired

Mobile telephones for the hearing impaired

Special rules of classification within this group
  • Classification should be directed to groups, H04R 25/02, H04R 25/04 and H04R 25/50 and its subgroups, if and only if the technical subject in consideration cannot be classified elsewhere under this main group.
  • Concerning inventions relating to hearing devices, if an application describes and shows the invention using only embodiments relating to hearing aids then H04R 25/00 or subgroups should be given as invention information. Dependent on the case, the mere statement that the invention is also applicable to ear- or headphones may render classification under H04R 1/10 or H04R 5/033 useful, but only as additional information. Only if specific non-trivial embodiments for ear- or headphones are also shown, classification under H04R 1/10 or H04R 5/033 as invention information may be considered as well.
  • Further detail is covered by Indexing Code groups H04R 2225/31, H04R 2225/33, H04R 2410/07, H04R 2430/03, H04R 2460/03, H04R 2460/13 and H04R 2460/17. Classification is obligatory.
Glossary of terms
In this group, the following terms (or expressions) are used with the meaning indicated:

Deaf aid

hearing aid, auditory prosthesis

Monitoring

encompasses indication

comprising pocket amplifiers
Definition statement
This subgroup covers:

The signal processing is done external to the hearing aid part that is in the ear (as for example shown in the figure)

media84.png

{Monitoring or testing of hearing aids, e.g. functioning, settings, battery power (testing arrangements for electro-acoustic transducers in general H04R 29/00; battery testing in general G01R 31/36)}
Definition statement
This subgroup covers:

For example testing of the functioning of an amplifier in a hearing aid (see figure). Switching circuit 20 measures a time period T, and interrupts the signal from the microphone 10 once every such period T. The interruption, or test time interval, lasts for another measured time segment t where t is less than T. During the interruption, the switching circuit 20 transmits the signal from the signal generator 22 to the hearing aid amplifier 12 to act as a test signal. Difference detector 24 detects malfunction of the amplifier. Difference detector 34 low battery status.

media85.png

Informative references
Attention is drawn to the following places, which may be of interest for search:

Testing arrangements for electro-acoustic transducers in general

Testing arrangements for cochlear implants

Battery testing in general

Indicators for indicating switching condition

For example: US4049930.

Special rules of classification within this group

Further detail is covered by Indexing Code group H04R 2460/15. Classification is obligatory.

Glossary of terms
In this subgroup, the following terms (or expressions) are used with the meaning indicated:

Monitoring

also encompasses indicating

{Self-monitoring or self-testing}
Definition statement
This subgroup covers:

Example of a self-diagnosis system with which the transducers and other component can be checked, see figure.

media86.png

Special rules of classification within this group

Further detail is covered by Indexing Code subgroup H04R 2225/39. Classification is obligatory.

{Frequency, e.g. frequency shift or compression}
Definition statement
This subgroup covers:

For example:

media87.png

{Amplitude, e.g. amplitude shift or compression}
Definition statement
This subgroup covers:

For example:

media88.png

Informative references
Attention is drawn to the following places, which may be of interest for search:

Compression/ expansion

Frequency-dependent volume compression or expansion in general, e.g. multiple-band systems

{using contructional means}
Informative references
Attention is drawn to the following places, which may be of interest for search:

Obtaining a desired directivity characteristic using constructional means in general

{by combining a plurality of transducers}
Definition statement
This subgroup covers:

Mechanical aspects, e.g. orientation, relative placement, of acoustic transducers in hearing aids to obtain a desired directional characteristic.

For example microphone openings (17A-17C) arranged along a straight line (see figure):

media89.png

For example microphones (8a,8b) mounted in a BTE housing and additional microphones (8c, 8d) mounted in a lever (4) which can be swung away from the housing to adapt the directivity of the hearing aid.

media90.png

Informative references
Attention is drawn to the following places, which may be of interest for search:

Arrangements for obtaining a desired directional characteristic by combining a number of identical acoustic transducers

Special rules of classification within this group

The mere fact that more than one microphone is used to obtain a desired directivity need not be classified, especially if H04R 25/407 has to be given anyway (cf. the first 2 EXAMPLES given for H04R 25/407).

Further detail is covered by Indexing Code group H04R 2410/01. Classification is obligatory.

{Circuits for combining signals of a plurality of transducers}
Definition statement
This subgroup covers:

For example:

media91.png

Informative references
Attention is drawn to the following places, which may be of interest for search:

Circuits for combining signals of a plurality of acoustic transducers in general

Direction-finders for determining the direction from which infrasonic, sonic, ultrasonic, not having a directional significance, are being received

Systems for determining distance or velocity not using reflection or re-radiation and using ultrasonic, sonic, or infrasonic waves

Circuits for sound-focusing or directing using electrical steering of transducer arrays, e.g. beam steering

Speech recognition techniques specially adapted for robustness in adverse environments

Speech enhancement using two microphones, one receiving mainly the noise signal and the other one mainly the speech signal

Speech enhancement using microphone arrays or beamforming

Telephonic conference arrangements

Video conference systems

Special rules of classification within this group

Further detail is covered by Indexing Code groups H04R 2410/01 and H04R 2430/20 listed below. Classification is obligatory.

{Electronic input selection or mixing based on input signal analysis, e.g. mixing or selection between microphone and telecoil or between microphones with different directivity characteristics (H04R 25/407 takes precedence)}
Definition statement
This subgroup covers:

Example for input selection:

media92.png

Example for mixing:

media93.png

{electronically (in general H04R 3/02)}
Informative references
Attention is drawn to the following places, which may be of interest for search:

Prevention of acoustic reaction in general

{mechanically}
Informative references
Attention is drawn to the following places, which may be of interest for search:

Mounting and assembly of hearing aids

Housing parts, e.g. shells, tips or moulds

Aspects relating to vents in hearing devices

{using constructional means for obtaining a desired frequency response (H04R 25/652 takes precedence; in general H04R 1/22)}
References relevant to classification in this group
This subgroup does not cover:

Ear tips; Ear moulds

Informative references
Attention is drawn to the following places, which may be of interest for search:

Constructional means for obtaining a desired frequency response in general

{Customised settings for obtaining desired overall acoustical characteristics}
Definition statement
This subgroup covers:

General analog or digital signal processing in hearing aid not provided for in H04R 25/00 or its subgroups.

Special rules of classification within this group
{using an external connection, either wireless or wired}
Definition statement
This subgroup covers:

External connection for the purpose of data exchange between hearing aids, e.g. binaural hearing aids, or between hearing aid and external device, e.g. telecoil, remote control, or for charging of batteries in hearing aids

Example for wirelessly charging accumulators in a hearing aid (see figure)

media94.png

Informative references
Attention is drawn to the following places, which may be of interest for search:

Transmission systems in which the medium consists of the human body

Special rules of classification within this group
{Binaural}
Definition statement
This subgroup covers:

Binaural control, e.g. control of one hearing aid in dependence of the other; Data exchange between hearing aids to enable binaural control, e.g. type of data, timing, ...

Special rules of classification within this group

The mere fact that binaural control of data exchange is wired or wireless needs not be classified.

{using a wireless connection, e.g. between microphone and amplifier or using T-coils (near-field transmission in general H04B 5/00)}
Definition statement
This subgroup covers:

Electric hearing aids using wireless connection for the transmission audio representative data, e.g. T-coils, FM receivers (see e.g. the figure below)

media95.png

Informative references
Attention is drawn to the following places, which may be of interest for search:

Wireless connection in general

Near field transmission in general

Transmission systems in which the medium consists of the human body

Non-intrusive coupling means between telephone set and auxiliary equipment

Special rules of classification within this group

Binaural hearing aids (invention) are not to be classified in this group but in H04R 25/552. No classification in H04R 25/554 (as invention of additional information) is in principle needed.

{External connectors, e.g. plugs or modules}
Definition statement
This subgroup covers:

Example for an ITE hearing aid connected to a programmer (5):

media96.png

Example for a BTE hearing aid additionally provided with an FM receiver (3):

media97.png

Informative references
Attention is drawn to the following places, which may be of interest for search:

Local control of medical devices, e.g. graphical user interfaces, dedicated hardware interfaces

Connectors in general

Special rules of classification within this group

Connection between the BTE housing and the earmould via an earhook is not to be classified here but in H04R 25/60 in combination with H04R 2225/63.

{Remote control, e.g. of amplification, frequency (remote control of amplifications, tone, or bandwidth H03G 1/02; remote control, e.g. for Hi-Fi systems or audio/video combinations H04B 1/202; remote control in general G05F)}
Informative references
Attention is drawn to the following places, which may be of interest for search:

Telemetry systems for implants such as pace makers or cochlear implants

Input or output devices integrated in time-pieces

Audio-frequency transformers or mutual inductances, i.e. not suitable for handling frequencies considerably beyond the audio range

Indicators for indicating switching condition

Remote control of amplification, tone, or bandwidth

Combined remote-control of tuning and other functions, e.g. brightness, amplification

remote control, e.g. for HiFi systems or audio/video combinations

{Mounting, assembling or interconnection of hearing aid parts, e.g. inside tips, housing or to ossicles; Apparatus or processes therefor}
Definition statement
This subgroup covers:

Arrangements for mounting or interconnection of hearing aid parts.

Example: Details of mounting of ear tip (11) via tube (21 to BTE housing (30):

media98.png

References relevant to classification in this subclass/group
This subgroup does not cover:

Ear wax retarders, e.g. their mounting

Special rules of classification within this group

Further detail is covered by Indexing Code subgroups H04R 2225/49, H04R 2225/59, H04R 2225/61, H04R 2225/63 and H04R 2225/67. Classification is obligatory.

Glossary of terms
In this subgroup, the following terms (or expressions) are used with the meaning indicated:

Interconnection

covers both mechanical as well as electrical interconnection

{Arrangements for mounting batteries (batteries in general H01M 2/02)}
Definition statement
This subgroup covers:

Arrangements for mounting or interconnection of batteries in hearing aids

Informative references
Attention is drawn to the following places, which may be of interest for search:

Electrical supply for implants, e.g. pace makers or cochlear implants

Battery holders in general

Cabinets, cases, fixing devices, adapters, racks for miniature batteries or batteries for portable equipment

Constructional aspects of miniature batteries or batteries for portable equipment

Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries

{Arrangements for mounting transducers}
Definition statement
This subgroup covers:

Arrangements for mounting or interconnection of transducers in hearing aids

{acting directly on the eardrum, the ossicles or the skull, e.g. mastoid, tooth, maxillary or mandibular bone, or mechanically stimulating the cochlea, e.g. at the oval window}
Definition statement
This subgroup covers:

Mounting or interconnection aspects of implantable hearing aid transducers

Informative references
Attention is drawn to the following places, which may be of interest for search:

Earphones or headphones using bone-conduction transducers

Constructions of transducers per se

Implantable hearing aids or parts thereof

Electrode placement of cochlear implants

Controlling aspects of cochlear implants

Electrical supply for implants

{Apparatus or processes specially adapted for mounting, assembling or interconnecting hearing aid parts inside tips, moulds or housings}
Special rules of classification within this subclass/group

This group is no longer used for classification, its content is transferred to H04R 25/60.

{Housing parts, e.g. shells, tips or moulds, or their manufacture}
Definition statement
This subgroup covers:

Example CIC: housing (15) and ear tip (18)

media99.png

Example ITE: housing (15) and ear mould (21)

media100.png

Example BTE: housing (17) and ear tip (20).

media101.png

Informative references
Attention is drawn to the following places, which may be of interest for search:

Hearing aid ear hooks

Constructional arrangements, e.g. casings, for implants

Storage case for drying purposes

Housing specially adapted for small components

Special rules of classification within this group

Further detail is covered by Indexing Code group H04R 2225/77. Classification is obligatory.

{Ear tips; Ear moulds}
Definition statement
This subgroup covers:

For examples, please see H04R 25/65.

Informative references
Attention is drawn to the following places, which may be of interest for search:

Earpieces of the intra-aural type

Measuring physical dimensions, e.g. size of the entire body or parts thereof

Earplugs for protection

Computer-aided design

Three dimensional (3D) modelling, e.g. data description of 3D objects

Special rules of classification within this group

Further detail is covered by Indexing Code groups H04R 2460/09 and H04R 2460/11. Classification is obligatory.

{Ear wax retarders}
Definition statement
This subgroup covers:

Means for protecting electric components, e.g. receivers, microphones, in hearing aids against e.g. earwax, oil, moisture, debris, and other foreign material; Their mounting or interconnection

Informative references
Attention is drawn to the following places, which may be of interest for search:

Screens for loudspeakers

Protective screens for microphones, e.g. all weather or wind screens

Mounting or interconnection of hearing aid parts in general, e.g. inside tips, housing or to ossicles

{Non-customized, universal ear tips, i.e. ear tips which are not specifically adapted to the size or shape of the ear or ear canal}
Definition statement
This subgroup covers:

Example BTE:

media102.png

Example ITE:

media103.png

Example CIC:

media104.png

{Manufacture of housing parts}
Definition statement
This subgroup covers:

Aspects of design and manufacturing of housing parts

Example of design and subsequent manufacture of ear mould:

media105.png

Example of design of a vent in a hearing aid shell (left-hand figure: general modelling and right-hand figure a method for optimising the shape of the vent)

media107.png

Informative references
Attention is drawn to the following places, which may be of interest for search:

Moulding of plastics

Shaping of plastics in general

{Adaptation of deaf aid to hearing loss, e.g. initial electronic fitting}
Definition statement
This subgroup covers:

Electronic adaptation of the hearing aid settings in response to audiological test signals to compensate for hearing aid loss or changes therein, i.e. initial or subsequent fitting.

Initial fitting is generally carried out by an acoustician. Subsequent fitting can be carried out by the acoustician or by the user, e.g. with audiological test signals generated in the hearing aid.

Informative references
Attention is drawn to the following places, which may be of interest for search:

Audiometering

Ear tip or ear moulds for hearing aids

Special rules of classification within this group

Further detail is covered by Indexing Code subgroups H04R 2225/39, H04R 2225/81 and H04R 2225/83. Classification is obligatory.

{Electric tinnitus maskers providing an auditory perception (evaluating tinnitus A61B 5/128; devices or methods to cause a change in the state of consciousness A61M 21/00; masking sound in general G10K 11/175)}
Definition statement
This subgroup covers:

Electric tinnitus maskers providing an auditory perception e.g. an acoustic noise signal around the tinnitus frequency. The tinnitus maskers can be stand-alone devices or can be integrated in a hearing aid.

Informative references
Attention is drawn to the following places, which may be of interest for search:

Evaluating tinnitus

Devices or methods to cause a change in the state of consciousness

Masking sound in general

Public address systems (circuits for preventing acoustic reaction H04R 3/02; circuits for distributing signals to loudspeakers H04R 3/12; {monitoring or testing arrangements for public address systems H04R 29/007}; amplifiers H03F)
Definition statement
This group covers:

Audio distribution systems for buildings, e.g. stations or religious facilities, for venues, e.g. in stadiums or in concerts halls, or for domestic use, i.e. multiroom.

Public address systems for buildings, e.g. stations or religious facilities, for open air, for indoor and outdoor venues, e.g. in stadiums or in concerts halls, or for domestic use, i.e. multiroom.

References relevant to classification in this group
This group does not cover:

Circuits for preventing acoustic reaction

Monitoring or testing arrangements for public address systems

Informative references
Attention is drawn to the following places, which may be of interest for search:

Circuits for distributing signals to loudspeakers in general

Audible signalling systems and audible personal calling systems

Audible advertising

Combined visual and audible advertising or displaying, e.g. for public address

Speech enhancement, e.g. noise reduction, echo cancellation in public address systems

Installations of electric cables or lines in or on buildings or equivalent structures

Amplifiers

Powerline communication in general

Audio/video applications of powerline communications

Broadcasting

Special rules of classification within this group

Further detail is covered by the subgroups of Indexing Code group H04R 2227/00 and by Indexing Code groups H04R 2420/05 and H04R 2430/03. Classification is obligatory.

Amplifying systems for the deaf
Definition statement
This subgroup covers:

Inductive loop or similar systems to enable communication with the hard of hearing.

References relevant to classification in this group
This subgroup does not cover:

Cochlear implants

Teaching or communicating with deaf persons

Electric hearing aids

Monitoring arrangements; Testing arrangements {(for hearing aids H04R 25/30; detection of loudspeaker connection H04R 5/04; sound-field adaptation dependent on speaker detection H04S 7/308)}
Definition statement
This group covers:
  • Monitoring or testing arrangements for transducers, loudspeakers, microphones or public address systems;
  • Testing of transducer, loudspeaker or microphone connection
  • Visual indication of acoustic signal levels.
References relevant to classification in this group

Examples of places where the subject matter of this group is covered when specially adapted, used for a particular purpose, or incorporated in a larger system:

Detection of loudspeaker or microphone connection for stereophonic purposes

Monitoring or testing of hearing aids

Circuits or components specially adapted for stereophonic broadcast systems

Informative references
Attention is drawn to the following places, which may be of interest for search:

Measurement of mechanical vibrations or ultrasonic, sonic or infrasonic waves, e.g. sound dosimeter

Testing of electronic circuits in household appliances or professional audio/video equipment

Sound-field adaptation dependent on speaker detection

Special rules of classification within this group

Further detail is covered by the subgroup of Indexing Code groups H04R 2420/05 and H04R 2430/03. Classification is obligatory.

Glossary of terms
In this group, the following terms (or expressions) are used with the meaning indicated:

Monitoring

encompasses indication

{for loudspeakers (H04R 29/007 takes precedence)}
Definition statement
This subgroup covers:

Loudspeaker 102 the one under test is in the exemplary figures below.

Loudspeaker 108 is the reference loudspeaker.

media109.png

media108.png

References relevant to classification in this group
This subgroup does not cover:

Testing or monitoring arrangements for public address systems

Informative references
Attention is drawn to the following places, which may be of interest for search:

Signal processing adapting stereophonic sound system to listener position

{Loudspeaker arrays}
Definition statement
This subgroup covers:

As an illustrative example:

media110.png

media111.png

{of the moving-coil type}
Definition statement
This subgroup covers:

For example:

media253.png

{for microphones (H04R 29/007 takes precedence)}
Definition statement
This subgroup covers:

Example for test method:

media250.png

Example for testing arrangement to test a plurality of microphones:

media115.png

References relevant to classification in this group
This subgroup does not cover:

Testing or monitoring arrangements for public address systems

{Microphone arrays}
Definition statement
This subgroup covers:

For example:

Functioning of the microphones (102a, 102b) is monitored (error detection 110) and if one microphone is considered defect, its signal is not used for further processing.

media116.png

media117.png

{Microphone matching}
Definition statement
This subgroup covers:

For example: US6272229.

For example: microphone matching in a microphone array in general

media251.png

media252.png

For example: microphone matching (CABLE) in an adaptive interference canceller (side-lobe canceller):

media120.png

{for public address systems (public address systems per se H04R 27/00)}
Definition statement
This subgroup covers:

For example:

In the PA system shown in the figure control device (CD) polls all monitoring devices 12,14 and line monitoring devices 16 to check if errors have occurred: Monitoring 12 checks for example whether the voice coil in the loudspeaker is an open connection (e.g. loudspeaker is defect)

media121.png

Informative references
Attention is drawn to the following places, which may be of interest for search:

Public address systems per se

Testing and monitoring for signalling and alarm systems

{Visual indication of individual signal levels (visual indication of stereophonic sound image H04S 7/40)}
Informative references
Attention is drawn to the following places, which may be of interest for search:

Indicating measured values

Arrangements for displaying electric variables or waveforms

Visual indication of stereophonic sound image

Apparatus or processes specially adapted for the manufacture of transducers or diaphragms therefor {(manufacture of microstructural arrangements of deformable or non-deformable structures in general B81C 1/00182)}
Definition statement
This group covers:

Apparatus or processes specially adapted for the manufacture of

  • acoustic transducers, including MEMS acoustic transducers
  • diaphragms therefor;
  • means for securing diaphragm or cone resiliently to support by flexible material, springs, cords, or strands for diaphragms.
Informative references
Attention is drawn to the following places, which may be of interest for search:

Microphones and microspeakers

Manufacture of microstructural arrangements of deformable or non-deformable structures in general

Packaging of Smart-MEMS, i.e. packaging together processing unit and MEMS

Interconnecting the MEMS and the processing unit

Processes for packaging MEMS

Pressure measurement / constructional details associated with semiconductive diaphragm sensors, e.g. etching of diaphragms

Special rules of classification within this group

Further detail is covered by Indexing Code groups H04R 2201/003, H04R 2231/001 and H04R 2231/003. Classification is obligatory.

{for diaphragms or their outer suspension}
Definition statement
This subgroup covers:

For example: Aluminium diaphragm (1) is pressed (5-7) out of an aluminium plate. The diaphragm is chemically treated cleaned (8-10) and the resulting diaphragm is treated with anodic oxidation to form an amorphous ceramic diaphragm of Al2O3. The amorphous diaphragm is heat treated to create corundum, a crystalline form of Al2O3.

media122.png

Informative references
Attention is drawn to the following places, which may be of interest for search:

Moulding of plastics

Shaping of plastics in general

Manufacture of micromechanical membranes and diaphragms

Electroplating

Anodizing of metals

Diaphragms for electromechanical transducers characterised by the construction

Securing diaphragm or cone resiliently to support by flexible material, springs, cords, or strands

Special rules of classification within this group

Further detail is covered by Indexing Code group H04R 2207/021 and the subgroups of H04R 2307/00. Classification is obligatory.

{Interconnection of transducer parts (of diaphragm and outer suspension by moulding H04R 31/003)}
Definition statement
This subgroup covers:

For example: A transducer is assembled with the help of jig 1 and jig 12 used for relative positioning of the parts during assembly. Jig 12 is removed before mounting of bottom frame 8. Jig 1 is removed after complete assembly.

media124.png

For example: A centre pole cap 88 is formed with cap die press 82. With help of pattern roller 82 an axial griping surface 92 is formed on the centre pole 16, after which the cap is pressed on the pole with press 86. The cap is held in place by interference fit.

media125.png

Informative references
Attention is drawn to the following places, which may be of interest for search:

Adhesives

Assembly of magnetic circuit for electrodynamic transducers

Mems transducers or their use (of the electrostatic type H04R 19/005)
References relevant to classification in this group
This subgroup does not cover:

Mems transducers of the electrostatic type

Informative references
Attention is drawn to the following places, which may be of interest for search:

Arrangements for avoiding sticking of the flexible or moving parts of MEMS devices having such parts

MEMS packages and encapsulations

Microphones and microspeakers

MEMS structures allowing for movement

Type of movement

Glossary of terms
In this subgroup, the following terms (or expressions) are used with the meaning indicated:

MEMS

Microelectromechanical system

Transducers or their casings adapted for mounting in or to a wall or ceiling
Informative references
Attention is drawn to the following places, which may be of interest for search:

Sound or noise insulation, absorption, or reflection

Room acoustics, i.e. forms of, or arrangements in, rooms for influencing or directing sound

Sound or noise insulation, absorption, or reflection of floors or ceilings

Sound or noise insulation, absorption, or reflection of flooring

Transducers incorporated in garment, rucksacks or the like
Definition statement
This subgroup covers:

For example:

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Informative references
Attention is drawn to the following places, which may be of interest for search:

Garments adapted to accommodate electronic equipment

Footwear provided with sound or music source

Structural combinations of loudspeakers with built-in power amplifiers, e.g. in the same acoustic enclosure (H04R 2499/10 takes precedence; Single (sub)woofer with two or more satellite loudspeakers for mid- and high-frequency band reproduction driven via the (sub)woofer H04R 2205/026)
Definition statement
This subgroup covers:

For example: (amplifier (10) mounted to transducer (20))

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(amplifier mounted to loudspeaker enclosure)

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For example: (the active loudspeaker (311,312) is placed in a separate enclosure (11,12) used in a television)

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References relevant to classification in this group
This subgroup does not cover:

General applications

Informative references
Attention is drawn to the following places, which may be of interest for search:

Single (sub)woofer with two or more satellite loudspeakers for mid- and high-frequency band reproduction driven via the (sub)woofer

Manufacturing aspects of enclosures transducers
Definition statement
This subgroup covers:

For example: manufacture of loudspeaker casing with backloaded horn using two lateral plates (1) and a plurality of intermediate plates (2) which are screwed together (6,7).

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For example: assembly of loudspeaker.

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Manufacture of mono- or stereophonic headphone components
Definition statement
This subgroup covers:

Typical components are earpiece supports, ear tips, and ear cushions, transducers specially adapted for earphones or headphones.

References relevant to classification in this group
This subgroup does not cover:

Manufacture of diaphragms for acoustic transducers

Informative references
Attention is drawn to the following places, which may be of interest for search:

Manufacture or assembly of earphones or headphones

Manufacturing aspects of the magnetic circuit of loudspeaker or microphone transducers

Monophonic and stereophonic headphones with microphone for two-way hands free communication
Definition statement
This subgroup covers:

For example: (monophonic: microphone (40)).

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For example: (stereophonic; microphone (30)).

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Arrangements to adapt hands free headphones for use on both ears
Definition statement
This subgroup covers:

For example: (monophonic) rotatable joint 25 enables rotation about axes B and C.

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For example US5210792 (monophonic): rotatable joints 28a and 28b enable rotation of the microphone arm 24 and of the earpiece, respectively.

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For example: (stereophonic) earpieces are releasably mounted using Velcro.

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Informative references
Attention is drawn to the following places, which may be of interest for search:

Mouthpieces and attachments therefor in general

Throat mountings for microphones

Transceivers carried on the body, e.g. in helmets

Substation equipment including speech amplifiers providing hands-free use or loudspeaker mode

Directing or guiding sound by means of a phase plug
Definition statement
This subgroup covers:

For example:US5933508 (phase plug of a compression driver), US2006153412 (phase plug used with a transducer).

For example: (phase plug (30) of a compression driver)

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For example: (phase plug used with a transducer)

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Beamforming aspects for stereophonic sound reproduction with loudspeaker arrays
Definition statement
This subgroup covers:

See for example: generation of multiple sound channels (12-1, 12-2) to reproduce stereophonic sound

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Informative references
Attention is drawn to the following places, which may be of interest for search:

Beamforming aspects for sound reproduction in general

Aspects relating to docking-station type assemblies to obtain an acoustical effect, e.g. the type of connection to external loudspeakers or housings, frequency improvement
Definition statement
This subgroup covers:

For example: (electric connection)

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JP2005136895 (acoustic connection)

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Informative references
Attention is drawn to the following places, which may be of interest for search:

External expansion units, e.g. docking stations

Cabinets for information storage devices; Cases; Stands; Disposition of apparatus therein or thereon

Disposition of constructional parts in the apparatus for information storage devices, e.g. of power supply, of modules

Side-by-side or stacked arrangements for casings, cabinets or drawers for electric apparatus

Plurality of transducers corresponding to a plurality of sound channels in each earpiece of headphones or in a single enclosure
Definition statement
This subgroup covers:

For example: (two-channel microphones in earpiece (2a, 2b) mounted on a spherical structure (1) for four-channel sound capture).

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For example: (multiple channels (20, 20’) in earpiece (30) of headphones).

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For example: (multiple channels in single loudspeaker box).

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For example: (multiple channels in single loudspeaker box, comprising a pistonic loudspeaker transducer (7) and a distributed mode panel (3) with exciters (5)).

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Informative references
Attention is drawn to the following places, which may be of interest for search:

Positioning of loudspeaker enclosures for spatial sound reproduction

Positioning of microphones for spatial sound recording in general

Positioning of loudspeaker enclosures for spatial sound reproduction
Definition statement
This subgroup covers:

Aspect relating to the relative positioning of loudspeaker enclosures, e.g. determination of their actual position

References relevant to classification in this subclass/group
This subgroup does not cover:

Mounting of transducers in earphones or headphones

Public address systems

Electronic adaptation of stereophonic sound system to listener position or orientation

Single (sub)woofer with two or more satellite loudspeakers for mid- and high-frequency band reproduction driven via the (sub)woofer
Definition statement
This subgroup covers:

For example:

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Adaptation of stereophonic signal reproduction for the hearing impaired
References relevant to classification in this subclass/group
This subgroup does not cover:

Deaf-aid sets

Informative references
Attention is drawn to the following places, which may be of interest for search:

Telephone sets for the hearing impaired

Mobile telephones for the hearing impaired

Diaphragm extensions, not necessarily integrally formed, e.g. skirts, rims, flanges
Definition statement
This subgroup covers:

For example: (flange (a) to prevent deformation of dome during firing to obtain a ceramic diaphragm

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For example: (annular skirt (54) extending from the dome (52), around which a voice coil is wound)

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Manufacturing aspects of the magnetic circuit of loudspeaker or microphone transducers
Informative references
Attention is drawn to the following places, which may be of interest for search:

Magnetic circuits for electrodynamic loudspeaker transducers

Magnetic materials, cores, yokes and magnets in general, and their manufacture

Transducers having separately controllable opposing diaphragms, e.g. for ring-tone and voice (H04R 2400/03 takes precedence)
References relevant to classification in this group
This subgroup does not cover:

Transducers capable of generating both sound as well as tactile vibration e.g. as used in cellular phones

Electrical or mechanical reduction of yoke vibration
Definition statement
This subgroup covers:

For example: (passive reduction with the help of a weight (23) mounted at the rear side of the magnetic circuit (25) of loudspeaker transducer (25)).

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For example (active reduction with the help of a second magnetic circuit (5B). This second magnetic circuit is similar to the first magnetic circuit (5A) driving the diaphragm (8 and attached thereto. Voice coil 7B is driven with part of the signal with which voice coil 7A is driven, such that a weight coupled to the coil 7B move in a direction opposite to that of the diaphragm (8)).

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Short circuited voice coils driven by induction
Definition statement
This subgroup covers:

For example: (short circuited moving coil (28) and static driving coil (23)

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Non-planar magnetostrictive, piezo-electric or electrostrictive benders
Definition statement
This subgroup covers:

For example: a flat bi-layer tape (21) extending around a minor axis (24) in a helix to form a helical electro-active structure extending along the minor axis (24). The tape can be used as shown in the right-hand figure to obtain a loudspeaker driver (480).

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Parametric transducers where sound is generated or captured by the acoustic demodulation of amplitude modulated ultrasonic waves
Definition statement
This subgroup covers:

Construction or application of such transducers. Sound generation may be using piezoelectric, electrostatic, or other principles.

For example: schematic driving circuit (14, 6, 27) for a parametric loudspeaker array comprising a plurality of modules (12, 29).

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An example for the modules used with the driving circuit above is shown in the figure directly below. A conductive electrode unit (32), a dielectric spacer (34) provided with an array of apertures (36), and a metallized polymer membrane (38). The components (32-38) are compressed against the spring (30) by an upper ring (40) that bears against the film (38) and threadably engages a base member (42) that supports the spring (30). The module (29) comprises a plurality of electrostatic transducers, corresponding with the respective apertures (36) in the polymer spacer (34).

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For example: sound reproduction for a TV, one parametric loudspeaker and one conventional nonparametric loudspeaker per channel.

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Synonyms and Keywords

In patent documents, the expression/word “parametric loudspeaker” is often used with the meaning “superdirective loudspeaker”.

Aspects of the use of accumulators in hearing aids, e.g. rechargeable batteries or fuel cells
Definition statement
This subgroup covers:

For example: Rechargeable battery (31) and battery charger 5 with charging contacts (51, 51’)

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For example: Fuel cell (6) with fuel cell tank (8). Valve (9) is used for filling the tank and with the help of window (10) the amount of fuel can be checked.

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For example: Thermic semiconductor elements (2) arranged on the outer surface of hearing aid.

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Informative references
Attention is drawn to the following places, which may be of interest for search:

For earphones and headphones

Reduction of energy consumption in hearing aids

Electrical supply for implants

Fuel cells

Secondary cells (accumulators)

Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries

Aspects relating to adaptation of the battery voltage, e.g. its regulation, increase or decrease
Definition statement
This subgroup covers:

For example: A hearing aid comprises a step-down/step-up converter (3) as voltage regulator, which transforms both higher as well as lower operating voltage into at least one stabilised supply voltage.

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For example: Power source (206) is connected to a charge pump and voltage regulator (208), which generates a larger or smaller output voltage depending on the value of the power source (206) and stabilises the output voltage.

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Aspects relating to automatic logging of sound environment parameters and the performance of the hearing aid during use, e.g. histogram logging, or of user selected programs or settings in the hearing aid, e.g. usage logging
Definition statement
This subgroup covers:

For example: Hearing aid with data logger (60) which logs data relating to sound environment, programs used, etc. The data stored can be used by subsequent fitting.

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Informative references
Attention is drawn to the following places, which may be of interest for search:

Hearing aid fitting

Adaptation of hearing aid parameters to listening situation

Detection or adaptation of hearing aid parameters or programs to listening situation, e.g. pub, forest
Definition statement
This subgroup covers:

For example: Acoustic scene identification method for hearing device, which involves extracting characteristic feature of input signal and generating revised class information in processing stages to characterize and identify acoustic scenes. The settings can be adapted to the encountered acoustic scene, if its characteristics are detected.

Glossary of terms
In this subgroup, the following terms (or expressions) are used with the meaning indicated:

Listening situation

Acoustic scene, acoustic environment

Signal processing in hearing aids to enhance the speech intelligibility
Definition statement
This subgroup covers:

Application of speech processing techniques, e.g. formant processing, determination or use of speech intelligibility threshold, detection of voiced speech, to control a hearing aid to enhance speech intelligibility.

Informative references
Attention is drawn to the following places, which may be of interest for search:

Speech enhancement, e.g. noise reduction or echo cancellation

Speech enhancement using noise filtering characterised by the method used for estimating noise

Special rules of classification within this subclass/group

The mere mentioning of increasing speech intelligibility, which is a general aim for hearing aids, should not be classified.

Reducing the effects of electromagnetic noise on the functioning of hearing aids, by, e.g. shielding, signal processing adaptation, selective (de)activation of electronic parts in hearing aid
Definition statement
This subgroup covers:

For example: Passive shielding of a microphone transducer (21) by metal jacket (30)

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For example: Active shielding by attenuation loops (8, 9) to attenuate electromagnetic interference resulting from supply lines (6C, 6D, coming from battery (6)) or the amplifier (3) and receiver (4) at the site of antenna (7)

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For example: Compensation for em-noise in signal processing:

A hearing aid receives the electromagnetic disturbance signal (14) via the detector element (12) and therefore detects the presence of, for example, a GSM telephone in the D1 network. The detector element (12) transmits the information about the detected noise field type (namely GSM telephone, D1 network) to the DSP element (3), so that the filter element (13) can be configured in a way that is adapted to the detected noise field type for the particularly effective noise field suppression.).

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Informative references
Attention is drawn to the following places, which may be of interest for search:

MEMS packages for protecting against electromagnetic or electrostatic interferences

Measuring electromagnetic field characteristics

Screening of apparatus or components against electric or magnetic fields

Aspects of antennas and their circuitry in and for hearing aids
Definition statement
This subgroup covers:

For example: Construction of the antenna

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For example: Circuitry for transmitting signal between hearing aid (2) and an external device (1):

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Informative references
Attention is drawn to the following places, which may be of interest for search:

Adaptation of aerials for carrying or wearing by persons or animals

Aerials using equipment having another main function to serve additionally as an aerial

Loop aerials

Hearing aid for unilateral hearing impairment using Contralateral Routing Of Signals [CROS]
Definition statement
This subgroup covers:

For example: Sound delivered to the deaf ear (18) is sent to the other ear (19) and processed to maintain some directional hearing.

If the other ear is also impaired it is called Bi-CROS.

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Communication between hearing aids and external devices via a network for data exchange
Definition statement
This subgroup covers:

For example:

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Informative references
Attention is drawn to the following places, which may be of interest for search:

Remote monitoring using telemetry, e.g. using a communication network

Home automation networks, e.g. Home Audio Video Interoperability [HAVI] networks

Arrangements for selective connection between one or more amplifiers and one or more receivers within one hearing aid
Definition statement
This subgroup covers:

For example: multiple amplifiers to one single receivers

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For example: multiple amplifiers to multiple receivers, with same or different characteristics

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Informative references
Attention is drawn to the following places, which may be of interest for search:

For stereophonic purposes

Connection circuits to selectively connect loudspeakers or headphones to amplifiers

Aspects relating to mechanical or electronic switches or control elements in hearing aids (H04R 2225/43 takes precedence)
Definition statement
This subgroup covers:

For example:

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References relevant to classification in this group
This subgroup does not cover:

Electronic input selection or mixing based on input signal analysis, e.g. mixing or selection between microphone and telecoil or between microphones with different directivity characteristics (H04R 25/407 takes precedence)

Signal processing in hearing aids to enhance the speech intelligibility

Informative references
Attention is drawn to the following places, which may be of interest for search:

For earphones or headphones

Switching (mechanical) in general

Switches in or for hearing aids in general

Electronic switching in general

Aspects relating to ear hooks or their connection to the hearing aid housing or ear mould
Definition statement
This subgroup covers:

Details regarding the interconnection between housing of a BTE hearing aid and the earmould. Generally the complete interconnection involves an earhook (13) or a connector portion (14) connected to the housing (12), which earhook or connector portion is connected to a tube (24) (hollow or with an electrical conductor). The tube is connected to the earmould (15)

For example:

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Implantable hearing aids or parts thereof not covered by H04R 25/606
Definition statement
This subgroup covers:

Implantable hearing aids or parts thereof, e.g. receivers, housings, whereas in H04R 25/606 the emphasis is on the mounting of the transducers.

Design aspects, e.g. CAD, of hearing aid tips, moulds or housings
Definition statement
This subgroup covers:

For example:

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Informative references
Attention is drawn to the following places, which may be of interest for search:

Computer aided design in general

Aspects of electrical fitting of hearing aids related to problems arising from the emotional state of a hearing aid user, e.g. nervousness or unwillingness during fitting
Definition statement
This subgroup covers:

For example: The ohmic resistance of the skin is measured. Under stress the ohmic resistance reduces due to sweating. Thus this resistance can be taken as a measure of psychoacoustic variables, e.g. loudness, sharpness, audio stress, etc.

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Aspects of electrical fitting of hearing aids related to problems arising from growth of the hearing aid user, e.g. children
Definition statement
This subgroup covers:

For example: compensation for the change in characteristics of a child’s ear during growth

Adaptation of signal processing in PA systems in dependence of presence of noise
Definition statement
This subgroup covers:

Adaptation of the signal processing is generally done by sensing the interference signal or noise. For example: A PA system has two audio inputs (6, 7) provided for interference signal and a utility signal, respectively. An adjustment device (11) adjusts the utility signal with the interference signal in such manner that a modified utility signal is produced. An audio output is provided for the modified utility signal. The interference signal contains information about local distribution of static noises.

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Digital PA systems using, e.g. LAN or internet
Definition statement
This subgroup covers:

For example:

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Informative references
Attention is drawn to the following places, which may be of interest for search:

Home automation networks, e.g. Home Audio Video Interoperability [HAVI] networks

Audio distribution systems for home, i.e. multi-room use
Definition statement
This subgroup covers:

For example:

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Informative references
Attention is drawn to the following places, which may be of interest for search:

Receiver circuits for HiFi systems or audio/video combinations

Audio mixers

Glossary of terms
In this subgroup, the following terms (or expressions) are used with the meaning indicated:

Room

zone

Electronic adaptation of audio signals to reverberation of the listening space for PA
Definition statement
This subgroup covers:

For example: reverberation adaptation for indoor or outdoor venues for PA-systems.

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Informative references
Attention is drawn to the following places, which may be of interest for search:

Measuring reverberation time; Room acoustic measurements

Arrangements for producing a reverberation or echo sound

For stereophonic systems

Signal processing in [PA] systems to enhance the speech intelligibility
Definition statement
This subgroup covers:

For example: Amplifiers (312) have the amplification gain, which is the function of the bandwidth (308) of the filter (306), thus effectively augmenting the speech in noisy conditions, and hence preserving the overall sound pressure level and increasing speech intelligibility. The appropriate amplifier/filter combination is selected by a switch (304), which can be manually or automatically controlled by a switch controller (316) (cf. figure).

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For example: A method involves sensing the ambient sound in a region for a predetermined time interval, analyzing sensed ambient sound and overlaying ambient sound with test audio signals having predetermined characteristics. The overlaid ambient sound is sensed. The degradation of speech intelligibility beyond acceptable level is determined by analyzing ambient sound pressure level and ambient frequency domain characteristics (cf. figure).

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Informative references
Attention is drawn to the following places, which may be of interest for search:

Speech enhancement using two microphones, one receiving mainly the noise signal and the other one mainly the speech signal

Moulding aspects of diaphragm or surround
Definition statement
This subgroup covers:

For example: Polypropylene pellets (61) are grinded (S01) to prepare granulated polypropylene resin (62). Fibres 63 are partly cut (S02; 64) and mixed (S03) with the resin to produce a compound (15 which can be injection moulded (S04, S05) to produce a loudspeaker diaphragm.

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Manufacturing aspects of the outer suspension of loudspeaker or microphone diaphragms or of their connecting aspects to said diaphragms
Definition statement
This subgroup covers:

For example: Surround press-moulded onto a loudspeaker diaphragm (7)

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Diaphragms comprising ceramic-like materials, e.g. pure ceramic, glass, boride, nitride, carbide, mica and carbon materials
Informative references
Attention is drawn to the following places, which may be of interest for search:

Anodizing of metals

Diaphragms comprising polymeric materials
Informative references
Attention is drawn to the following places, which may be of interest for search:

Moulding of plastics

Shaping of plastics in general

Moulding aspects of diaphragm or surround

Diaphragms comprising metallic materials
Informative references
Attention is drawn to the following places, which may be of interest for search:
Damping aspects of the outer suspension of loudspeaker diaphragms by addition of additional damping means
Definition statement
This subgroup covers:

For example: membrane (2) is extended to form outer suspension (21), whose elastic properties are adapted by the elastic layer (22).

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For example: dampening material (20) for the edge (14a)

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Glossary of terms
In this subgroup, the following terms (or expressions) are used with the meaning indicated:

Outer suspension

surround

Shape aspects of the outer suspension of loudspeaker diaphragms
Definition statement
This subgroup covers:

For example: Pleats (26,27, 28,32, 33,34, 38,39, 40) are provided in the outer suspension in such a way the vibration of membrane is more uniform over the frequency range the transducer is to be used for.

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Glossary of terms
In this subgroup, the following terms (or expressions) are used with the meaning indicated:

Outer suspension

surround

Loudspeakers
Special rules of classification within this group

Only for those cases where the classification does not allow specification the type of transducer and the type is important, e.g. frequency control circuit (H04R 3/04 and subgroups) may require different circuit for microphones or for loudspeakers

Transducers used as a loudspeaker to generate sound aswell as a microphone to detect sound
Definition statement
This subgroup covers:

For example: US2002137478.

For example: Cellular telephone (1) has pair of transducers (8A,8B) functioning as stereo speakers during sound reproduction and functioning separately as speaker (8A) and microphone (8B) during conversation.

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Transducers capable of generating both sound as well as tactile vibration, e.g. as used in cellular phones
Informative references
Attention is drawn to the following places, which may be of interest for search:

Generating mechanical vibrations with vibrating magnet, armature or coil system;

Tactile signalling systems

Moving coil loudspeaker transducers

Moving armature loudspeaker transducers

Suspension between moving magnetic core and housing
Definition statement
This subgroup covers:

For example: The transducer shown in the figure below, comprises magnetic circuit (103, 104, 105) and a movable diaphragm (101) to produce sound when the voice coil (102) is supplied with a signal having a higher frequency. When the magnetic circuit and a weight (106) constitute a vibrator which is elastically supported against the case (110) by an upper and a lower suspension (107, 108). If the voice coil is supplied with a low frequency signal the vibrator starts vibrating, resulting in a tactile vibration.

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For example: an inertial transducer with a flexible membrane (3’) and magnetic circuit elastically supported by a suspension (9). Upon energising the voice coil (4b) the membrane starts producing sound and the magnetic circuit move as well, causing a tactile vibration to be simultaneously generated.

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Use or details of compression drivers
Definition statement
This subgroup covers:

For example: Details of construction of a compression driver.

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Microphones
Special rules of classification within this subclass/group

Only for those cases where the classification does not allow specification the type of transducer and the type is important, e.g. frequency control circuit (H04R 3/04 and subgroups) may require different circuit for microphones or for loudspeakers

Noise reduction using microphones having different directional characteristics
Definition statement
This subgroup covers:

For example: In this particular example the far field microphone is omnidirectional and the near field microphone is directional

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Informative references
Attention is drawn to the following places, which may be of interest for search:

Electronic input selection in hearing aids based on input signal analysis

Reduction of intrinsic noise in microphones
Definition statement
This subgroup covers:

Intrinsic noise is the noise which is generated inside the microphone (transducer) without any ambient acoustic signal (noise) being present, e.g. noise caused by parasitic capacitances in MEMS microphones or thermal noise.

Noise reduction with a separate noise microphone
Informative references
Attention is drawn to the following places, which may be of interest for search:

Speech enhancement using two microphones, one receiving mainly the noise signal, and the other one mainly the speech signal

Mechanical or electrical reduction of wind noise generated by wind passing a microphone
Definition statement
This subgroup covers:

For example: mechanical reduction with the help of a mesh (6,6’,6’’) over the sound openings (5,5’,5’’) of a microphone

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For example: electrical reduction using primary microphone (1) and a reference microphone (2) placed closely together. The microphone signals are input to adaptive noise canceller (6) (cf. Figure below).

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Informative references
Attention is drawn to the following places, which may be of interest for search:

Speech enhancement using noise filtering

Speech enhancement using noise filtering characterised by the method used for estimating noise

Input selection or mixing for amplifiers or loudspeakers (for hearing aids H04R 25/43)
Definition statement
This subgroup covers:

For example: selection

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For example: mixing

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Informative references
Attention is drawn to the following places, which may be of interest for search:

Audio mixers

Connection circuits to selectively connect loudspeakers or headphones to amplifiers
Definition statement
This subgroup covers:

For example:

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References relevant to classification in this group
This subgroup does not cover:

Public address systems

Detection of connection of loudspeakers or headphones to amplifiers
Definition statement
This subgroup covers:

Detection of state of connection of acoustic transducers, microphones, loudspeakers and headphones to amplifiers

For example: The information apparatus (100) includes speakers (FLS, FRS, RLS, RRS) connected to the amplifiers (12a-12d). An input switch circuit (22) performs the input of a predetermined inspection signal into the amplifier. A microcomputer (23) determines whether the speaker is connected to the amplifier based on a signal to be inspected which is produced from the input inspection signal in the input switch circuit (cf. Figure).

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Informative references
Attention is drawn to the following places, which may be of interest for search:

Means for preventing incorrect coupling by indicating incorrect coupling; by indicating correct or full engagement

Special rules of classification within this subclass/group

To be used in combination with H04R 5/04 (stereophonic) or H04R 29/00 (not stereophonic) (or its subgroups) to indicate detection of connection.

Applications of wireless loudspeakers or wireless microphones
Definition statement
This subgroup covers:

For example: stand for a microphone (not shown) having an antenna (3) and a transmitter (45))

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For example: loudspeaker

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References relevant to classification in this group
This subgroup does not cover:

Wireless connection for hearing aids

Informative references
Attention is drawn to the following places, which may be of interest for search:

Arrangements for transmitting signals characterised by the use of a wireless electrical link.

Portable transmitters

Near-field transmission systems using a receiver structurally associated with a loudspeaker or an earphone

Near-field transmission systems using a portable transmitter associated with a microphone

Indoor or near-field type systems for optical communication

Hands-free substation equipment including a wireless connection or interface

Special rules of classification within this group

The mere fact that a wireless connection for data transfer is used should not be classified.

Applications of special connectors, e.g. USB, XLR, in loudspeakers, microphones or headphones
Informative references
Attention is drawn to the following places, which may be of interest for search:

External connectors, e.g. plugs, modules for hearing aids

Aspects of volume control, not necessarily automatic, in sound systems
Definition statement
This subgroup covers:

Electronic aspects of volume control, e.g. for control based on sensor signals or for limiting the maximum sound level, or aspects of elements used for volume control, e.g. for simplicity in use or the construction of control element.

The mere presence of a volume control should not be classified.

Example (electronic aspects of volume control): The volume level set by the gain controller (205) of a headphone is determined in dependence of the ambient signal (B) picked up by a microphone (109) and an attenuated version (A) thereof.

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Example (aspects of the element used for control): The earphone 10 has a front side 12, from which sound is emitted from a speaker, and a back side 14 which the user can press with the user's finger or hand 15 in order to activate a switch that raises the volume level of the sound produced by the earphone 10.

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Informative references
Attention is drawn to the following places, which may be of interest for search:

Control of amplification per se

Automatic control of amplifiers dependent upon ambient noise level or sound level

Synergistic effects of band splitting and sub-band processing
Definition statement
This subgroup covers:

For example: EP1471765, US4953216, DE19632734.

Only if additional effects due to the combination of band splitting and sub-band processing are present (cf. the examples below).

The mere fact that band splitting and sub-band processing is applied should not be classified.

For example: Adaptive feedback cancellation for individual frequency band, which reduces computational effort, thus making cancellation faster and a good sound quality can be maintained.

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For example: For each frequency band (122a, 12b, ...) an automatic threshold switch (13a, 13b, ...) is opened if speech is present. Thus noise is only transmitted in the presence of louder speech in a frequency band and is suppressed if no speech is present in said band. Because the unwanted signals are transmitted only in those frequency channels wherein louder speech signals are simultaneously present, the unwanted signals are always covered by the louder speech signals, and the unwanted signals are thus no longer audible.

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Informative references
Attention is drawn to the following places, which may be of interest for search:

Crossover filters for loudspeakers

Digital filter banks

Special rules of classification within this group

The mere band splitting or presence of a filter bank (e.g. FFT or FIR) should not be classified.

Glossary of terms
In this subgroup, the following terms (or expressions) are used with the meaning indicated:

Deaf aid

hearing aid, auditory prosthesis

Stereophonic system

two- or more channel system, e.g. quadraphonic, ambisonic or similar systems

Processing of the output signals of the acoustic transducers of an array for obtaining a desired directivity characteristic (H04R 2203/12 takes precedence)
Definition statement
This subgroup covers:

Signal processing of the output signals of an array of microphones for direction finding or of the input signals of an array of loudspeakers for steering sound in a desired direction

References relevant to classification in this group
This subgroup does not cover:

Beamforming aspects for stereophonic sound reproduction with loudspeaker arrays

Array processing for suppression of unwanted side-lobes in directivity characteristics, e.g. a blocking matrix
Definition statement
This subgroup covers:

For example: microphone array

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For example: loudspeaker array comprising additionally high-directivity edge loudspeakers which are driven with only low-frequency signal, to cancel side-lobes.

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Acoustic transducers using travelling bending waves to generate or detect sound
Informative references
Attention is drawn to the following places, which may be of interest for search:

Plane diaphragms using the distributed mode principle

Aspects relating to the positioning and way or means of mounting of exciters to resonant bending wave panels
Definition statement
This subgroup covers:

For example: Repositioning of central exciter (42) which has to be positioned at the edge of a transparent panel to be used for a visual display.

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For example: mounting of the exciter (9) in the panel (2) (upper figure) or on the panel (2) (lower figure).

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Loudspeakers using bending wave resonance and pistonic motion to generate sound
Definition statement
This subgroup covers:

For example: Bending wave resonance speaker (1) for surround channels and pistonic loudspeaker transducer (7) for the main channel

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For example: The membrane (2) of loudspeaker (81) is actively driven with resonant bending waves by an exciter (9) for the high frequencies and is passively driven by a pistonic loudspeaker transducer (42) for the low frequencies.

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Hearing devices using active noise cancellation
Definition statement
This subgroup covers:

For example: US6661901 (earphone and hearing aid).

Informative references
Attention is drawn to the following places, which may be of interest for search:

Reduction of ambient noise in headphones in general

Ear defenders (electric or acoustic)

Active noise cancellation in general

Active noise control in general for earphones or microphones

Aspects of the reduction of energy consumption in hearing devices
Definition statement
This subgroup covers:

For example:

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Informative references
Attention is drawn to the following places, which may be of interest for search:

Battery saving arrangements in cordless telephones

Electronic compensation of the occlusion effect
Definition statement
This subgroup covers:

For example: Fitting a hearing aid including occlusion compensation filter (C).

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Informative references
Attention is drawn to the following places, which may be of interest for search:

Non-occlusive ear tips, i.e. leaving the ear canal open, for both custom and non-custom tips

Aspects relating to vents, e.g. shape, orientation, acoustic properties in ear tips of hearing aids to prevent occlusion

Non-occlusive ear tips, i.e. leaving the ear canal open, for both custom and non-custom tips (H04R 2460/11 takes precedence)
Definition statement
This subgroup covers:

For example:

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References relevant to classification in this group
This subgroup does not cover:

Aspects relating to vents, e.g. shape, orientation, acoustic properties in ear tips of hearing aids to prevent occlusion

Aspects relating to vents, e.g. shape, orientation, acoustic properties in ear tips of hearing devices to prevent occlusion
Definition statement
This subgroup covers:

For example: Improved venting of the ear canal due to the opposite orientation of valves (25, 26), which enables circulation (29) of air in the ear canal.

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For example: hearing aid device with a ventilation channel (5), cross-section of which can be adapted (6, 7) to the respective acoustic situation (e.g. acoustic feedback) in a fast and simple manner.

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Informative references
Attention is drawn to the following places, which may be of interest for search:

Prevention of acoustic feedback in hearing aids mechanically

Electronic compensation of the occlusion effect

Determination of the acoustic seal of ear moulds or ear tips of hearing devices
Definition statement
This subgroup covers:

For example:

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Hearing device specific tools used for storing or handling hearing devices or parts thereof, e.g. placement in the ear, replacement of cerumen barriers, repair, cleaning hearing devices
Definition statement
This subgroup covers:

For example: Haring aid (12) cleaning: a cleaning liquid (28) is pump up (with a pump system (252)) from a cartridge (224) into a reservoir (229) (cf. figure)

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For example: Tool for replacement of cerumen barriers: a cerumen barrier (19) is provided with two holes (21, 22) (upper figure). The tool (lower figure) (31) is provided with two pins (35, 36) which fit in said holes (21, 22) of the cerumen barrier. Thus the barrier can be easily screwed onto the outside thread (4) of the neck (3) of the ITE hearing aid module (1).

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For example: hearing aid storage box: When the lid (5) is closed the protrusion (7) pushes the on/off switch (3) in the off position.

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For example: safety loop for securing an earbud to e.g. a shirt.

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Transducers incorporated or for use in hand-held devices, e.g. mobile phones, PDA's, camera's
Informative references
Attention is drawn to the following places, which may be of interest for search:

Mountings specially adapted for telephone equipment

Improving the acoustic characteristics by means of constructional features of the housing (of telephone equipment), e.g. ribs, walls, resonating chambers or cavities

Supports for telephone transmitters and receivers

Substation equipment with increased funcionallity, e.g. for playing back music files

Acoustic transducers and sound field adaptation in vehicles
Definition statement
This subgroup covers:

For example: US6389147, EP1482763.

Subject matter relating to mounting of transducers on or within a vehicle, e.g. automobile, aircraft, motorcycle, and to electronic control of the sound field within a vehicle, e.g. automobile, aircraft, motorcycle.

For example: Mounting of transducers in vehicles

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For example: Sound control in vehicles

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Informative references
Attention is drawn to the following places, which may be of interest for search:

Mounting of acoustic transducers in vehicles

Automatic control of amplifiers dependent upon ambient noise level or sound level

Glossary of terms
In this subgroup, the following terms (or expressions) are used with the meaning indicated:

Stereophonic system

two- or more channel system, e.g. quadraphonic, ambisonic or similar systems

Multi-channel system

three- or more channel system

Transducers incorporated in visual displaying devices, e.g. televisions, computer displays, laptops
Informative references
Attention is drawn to the following places, which may be of interest for search:

Details related to the integrated loudspeakers in data processing equipment

Loudspeakers in televisions

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Last Modified: 10/11/2013