The subject matter of starting, regulating, electronically commutating, braking, or otherwise controlling the machines covered by this subclass is classified in subclass H02P.

Measuring the electric or magnetic variables involved in the functioning of the machines covered by this subclass is classified in subclass G01R.

Electric machines not based on dynamo-electric interaction, like e.g. electrostatic machines, piezoelectric actuators, electric motors using thermal effects, or electric machines based on not otherwise provided effects, are classified in subclass H02N.

The structural association with loads / prime motors can be classified either in H02K, or in the subclass covering the load / prime motor involved, or in both the subclasses, depending on which aspect is relevant. Relevant aspects of the dynamo-electric machine should always be classified in H02K, unless a reference explicitly indicate otherwise; on the contrary dynamo-electric machines only schematically represented in an a specific application (e.g. a wind turbine) are not classified in H02K and should only be classified in the relative application-oriented place.

The structural association with a specific component (e.g. connectors, bearings, sensors, magnetic and electric elements per se etc.) is classified, if relevant, in H02K. On the contrary specific aspects of the component, relevant for the component but not for the structural association with the electro-dynamic machine, are not classified in H02K and should only be classified in the relative function-oriented place.

Groups H02K 1/00-H02K 13/00 and H02K 17/00-H02K 99/00.

Details or general arrangements only applicable to specific dynamoelectric machines of a single basic type, are classified in the group (H02K 17/00-H02K 99/00) appropriate to the dynamo-electric machines of that basic type, e.g. H02K 21/12 (unless a specific group for this details exists in the details group, e.g. H02K 1/27).

Details or arrangements for a generic type of dynamo-electric machine (i.e. for a machine of unspecified type, or disclosed as applicable to two or more kinds of machines, or in any case not necessarily related to a specific type of machine) are classified in groups H02K 1/00-H02K 13/00.

The above mentioned rules for "special" machines covered by groups H02K 24/00 - H02K 26/00, H02K 31/00-H02K 35/00, H02K 41/00-H02K 99/00 are applied in the following way:

the document is always classified as invention information in the corresponding machine group, e.g. H02K 41/03;

relevant details which are not specific of the "special" machine (i.e. which could be used in any type of machine) are classified as invention in the corresponding detail groups (H02K 1/00-H02K 13/00);

on the contrary relevant details which are specific of the "special" machine, although invention information, are classified as additional information in the corresponding detail groups (H02K 1/00-H02K 13/00).

H02K 16/00 takes precedence over groups H02K 17/00-H02K 53/00. A machine consisting of a combination of two or more machines of the type covered in groups H02K 17/00-H02K 53/00 should also be classified as additional information in the groups corresponding to said machines.

Classification of additional information.

For example, a connector (H02K 5/225) in a geared motor (H02K 7/116) is classified:

only in H02K 5/225 as invention information if the connector is the invention and the fact that the machine is a gear motor is not relevant at all;

in H02K 5/225 as invention information and H02K 7/116 as additional information if the connector is the invention and the fact that the machine is a gear motor, although not interesting per se, could be a useful information for a search;

in both H02K 5/225 and H02K 7/116 as invention information if, beside the connector, the geared motor presents other inventive aspects covered by H02K 7/116;

in H02K 7/116 as invention information and H02K 5/225 as additional information if the invention refers to the gear motor, and the connector although not interesting per se, could contain useful information for a search;

in both / either / neither H02K 5/225, H02K 7/116 as additional information if the invention relates to some other aspect (which is classified as invention information in another subgroup) and both / either / neither the connector and the type of machine contain information which could play a role in a search.

Classification in a subgroup.

The subgroups characterised by a specific feature, e.g. H02K 1/165 (which is characterized by the form or location of the slot), cover only said specific feature. Documents comprising also other relevant features covered by the head group (e.g. H02K 1/16) should therefore also be classified in said head group (or, if appropriate, in relevant subgroups of said head group).

Subgroups being a subdivision based on general typological considerations of a larger group, e.g. H02K 21/14, H02K 21/22, H02K 21/24 (which are subdivisions of H02K 21/12 for PM machines with respectively inner rotor, outer rotor and axial rotor) cover all the machines / machine elements of a certain type. Documents in these subgroups are generally classified according to their type (e.g. inner / outer rotors) also when their relevant features are not specific to said type. Documents are classified in the head group (e.g. H02K 21/12) if the machine / machine element type is not clear, or if several types are only schematically indicated. In this latter case the document can also be classified as additional information in the concerned subgroups.

Documents concerning aspects which are covered by several subgroups dependent on the same higher hierarchy group (e.g. H02K 7/102-H02K 7/12, depending on H02K 7/10):

if it is the combination of the aspects covered by the subgroups which is relevant, the document is classified as invention information in the head group (e.g. H02K 7/10); furthermore the document should also be classified as additional information in all the concerned subgroups;

if the aspects covered by the subgroups are per se relevant (and not the combination), the document is classified as invention information in the subgroups for which relevant information is present.

A combination of the two cases is possible.

Example:

a motor comprising a gear box and a brake should be classified:

if only the combination of the brake and the gear is relevant (the brake and the gear being per se well known): in H02K 7/10 as invention, in H02K 7/102 and H02K 7/116 as additional information;

if beside the combination also the brake is relevant per se: in H02K 7/10 and H02K 7/102 as invention, in H02K 7/116 as additional information;

if the brake and the gear are relevant per se and the combination is obvious: in H02K 7/102 and H02K 7/116 as invention.

The groups H02K 2201/00 - H02K 2213/00 are used as transversal classification scheme to tag aspects, not otherwise provided for in this subclass.

Old documents relating to magnetic circuits characterised by the unusual type of magnetic material and without indication of the chemical composition could also be found in H02K 1/06 and subgroups.

Materials used for insulating or coating the magnetic circuit.

Certain details of non-magnetic parts , e.g. windage screens between salient poles, are classified in the group of the corresponding magnetic circuit part.

Air gap shapes:

when obtained by a generic combination of shapes of both the rotor and the stator are classified in H02K 1/06;

when obtained by a specific shape of either the rotor or the stator (the other member being normal) are classified in the subgroup specific for the member with the specific shape.

In any case relevant aspects of the air gap should be also classified in H02K 2201/03.

Following the rules of classification within this subclass:

a combination of stator and rotor features for a generic machine (i.e. not necessarily related to a specific type of machine) is classified in this group;

a combination of stator and rotor features which necessarily relates to a specific type of machine (e.g. a particular ratio of rotor and stator pole numbers, or a particular combination of rotor and stator pole shapes, for reducing torque ripples in a brushless motor) is classified in the group appropriate to said specific machine (e.g. H02K 29/03).

Poles in general (i.e. which could be either for rotors or stators)

This group mainly contains old documents and is rarely used, most of the documents with salient poles being classified in the relevant subgroups of H02K 1/12, H02K 1/22.

Stators consisting of a single, or of a plurality of separate I, E or similarly shaped cores, are classified in H02K 1/14. The I, E-shaped cores must be at least magnetically separated, but can be mechanically linked by tiny bridges (e.g. Fig. 12-15 in EP1248347)

I, E or similarly shaped cores which are not magnetically isolated, but are joined together to form a core, e.g. in which the magnetic flux can circulate in all the parts of the "annular" back iron are classified in H02K 1/148

Stators consisting of single or multiple C or U-shaped cores, separated or joined together, wherein the C or U-shaped core must have the poles at the two ends of the C/U (e.g. EP0743737, fig 14) and not in its centre. The C or U-shaped cores can consist of separate parts (e.g. WO9624187, fig. 1-12)

The C or U-shaped cores can be joined together, but they must be still clearly recognisable as C/U shapes (e.g. WO9624187, fig. 18-40); if they are combined and modified (e.g. two cores with some part in common) or combined with non-C-shaped cores, they are classified in H02K 1/14 .

Cores having one or more annular coils which are coaxial with the rotor axis.

This group covers annular undulated coils (e.g. fig 3, DE29623132U) only, if the undulation is not excessive. Annular coils with broad undulation ,see e.g. fig. 7-9 DE29623132U, are classified in H02K 1/146.

Annular cores or cores forming a closed circuit.

The shape of the "annular" ring must be a close circuit but it can have any shape, circular, rectangular etc.

The poles can extend radially or axially, be asymmetrical or even consist of only one salient pole.

The stator can be annular in the circumferential direction (very common), but the annular form can even lay in a plane containing the axis.

Cores of the general shape, but consisting of more than one part when seen in a section perpendicular to the rotor axis, e.g. parts joined together

Cores consisting of several annular parts, e.g. each made of one single piece, stacked axially and skewed are classified in H02K 1/146. Single packages of laminations consisting of sectional laminations (typically stacked axially and shifted around the axial direction), are also classified in H02K 1/146.

Cores consisting of strings of (e.g. T-shaped) elements, linked by mechanically links are normally classified in this group, unless the link is very thick (H02K 1/146).

It is not always evident to differentiate between cores with slots / teeth and cores with numerous salient poles. The terminology used in the patent is taken into consideration but not decisive. When possible the type of winding is used as discriminating factor (concentrate winding being usually used around salient poles and distributed winding in cores with slots).

Stator cores with every kind of slot, punched or not, are classified here, but older documents relating to non-punched slots could also be found in H02K 1/12

Constructional aspects of PM (permanent magnet) stator cores e.g.:

positioning and / or fixation of the magnets to the back iron / housing or of the back iron to the housing;

protection of the magnets (also against corrosion);

Magnetic aspects of stator cores in unspecified machines.

Means for mounting or fastening cores with PM are classified:

if the means are only suitable for PM arrangements: H02K 1/17;

if the means are suitable for magnetic cores in general (with or without PM): H02K 1/18. Further classification as additional information is made in H02K 1/17 whenever appropriate.

The back irons of H02K 1/17 machines without casing are classified here and not in H02K 5/04 (and subgroups); however the simple fixation of a tubular back iron to the end shield are classified in H02K 5/15

Mounting means between casing or similar support structures and magnetic stationary parts.

Means for mounting or fastening, including vibration dampers, magnetic stationary parts are classified in:

Means for mounting or fastening cores with PM are classified:

Further classification as additional information is made in H02K 1/17 whenever appropriate.

The fixation of magnetic stationary parts with other magnetic stationary parts, e.g. fixing the laminations together to form a lamination package, is classified in H02K 1/14 - H02K 1/17.

The fixation of I, E or similarly shaped cores (e.g. DE102010015441) is classified in H02K 1/18 as invention and in H02K 1/14 as additional information.

Mounting means for machines with more than one stator (with the exception of axial air gap machines), e.g. with inner and outer stators are classified in H02K 1/18 (not in the subgroups)

Rotors with permanent magnets (PM) and magnetisation windings or short-circuit windings

Only the combination of PM and windings is classified in the groups H02K 1/223, H02K 21/04 and H02K 21/46; if other aspects relevant for a specific subgroup of H02K 1/22 are present, the document should also be classified in the relevant subgroup thereof.

Minor modifications of the core only related to the problem of fastening the coil

Details of reluctance rotors including reluctance rotors with additional permanent magnets, when the function of the magnets is not the generation of extra excitation field but the achievement of an additional secondary effect, e.g. flux guide/reduction of stray flux.

PM rotors have sometimes some reluctance effect i.e. some low / high reluctance path, while reluctance rotors can comprise auxiliary PM e.g. for reducing the stray fields along the quadrature axis. The rule of classification is the following:

rotors of the PM type (where the PMs generate the excitation field) with a secondary and well known reluctance effect (this is often the case for embedded PM rotors like DE102005062922 figure 8): H02K 1/27;

rotors of PM type with an interesting although secondary reluctance effect (EP1830451, figure 1b): H02K 1/27 (invention), H02K 1/246 (additional information);

rotors with both relevant PM and reluctance features (including doubtful cases, in which it is not clear whether the rotor are PM rotors with consistent auxiliary reluctance features or reluctance rotors with consistent auxiliary PM, see e.g. DE102005062922 figures 2, 3, 6, 7): H02K 1/27 (invention) and H02K 1/246 (invention);

reluctance rotors with auxiliary PM having an additional secondary effect (e.g. flux guide/reduction of stray or quadrature flux, see e.g. EP1837980, the figures 3, 4): H02K 1/246 (invention) and H02K 1/27 (additional information);

Means for mounting or fastening cores with PM are classified:

Further classification as additional information is made in H02K 1/27 whenever appropriate.

PM rotors have sometimes some reluctance effect i.e. some low / high reluctance path, while reluctance rotors can comprise auxiliary PM e.g. for reducing the stray fields along the quadrature axis. The rule of classification is the following:

rotors of the PM type (where the PMs generate the excitation field) with a secondary and well known reluctance effect (this is often the case for embedded PM rotors like DE102005062922 figure 8): H02K 1/27;

rotors of PM type with an interesting although secondary reluctance effect (EP1830451, figure 1b): H02K 1/27 (invention), H02K 1/246 (additional information);

rotors with both relevant PM and reluctance features (including doubtful cases, in which it is not clear whether the rotor are PM rotors with consistent auxiliary reluctance features or reluctance rotors with consistent auxiliary PM, see e.g. DE102005062922 figures 2, 3, 6, 7): H02K 1/27 (invention) and H02K 1/246 (invention);

reluctance rotors with auxiliary PM having an additional secondary effect (e.g. flux guide/reduction of stray or quadrature flux, see e.g. EP1837980, the figures 3, 4): H02K 1/246 (invention) and H02K 1/27 (additional information).

Rotors between inner and outer stators, e.g. for transversal flux machines and combined outer and inner rotors (also with magnets on one side only) are classified in H02K 1/27 (not in the subgroups)

Annular magnets (including special forms like US4857786, figure 6)

Arrangements consisting of a plurality of magnets presenting in the circumferential direction the same, i.e. not alternating, polarity;

Magnets embedded in a magnetic core;

Magnets mounted on the surface of a magnetic core, but with polar extensions, pole shoes (even thin, e.g. EP1829188, figure 1, magnetic pole shoe 12).

The following cases are classified as follows:

Rotors with magnets located in pockets provided in the laminations, even if the outer thickness of the pockets is small (US2006131976, figure 2), are classified in H02K 1/276.

Rotors comprising a thin sleeve or similar cylindrical bandages, magnetic or not (EP1830451, figure 3) are classified in H02K 1/278.

However thick magnetic sleeves are classified in H02K 1/276.

The classical case of 4 or 6 radial magnets magnetized along the circumference (e.g. CH217877, figures 2 and 3) is classified in H02K 1/2773. However, when only 2 magnets are present (CH217877 figure 1), then, classification is made in H02K 1/276.

Embedded magnets having any type of configuration that involves the concentration of flux generated by magnets

All the magnets have to be disposed radially (i.e. each magnet has to be placed along a radius) and to be magnetized tangentially to the rotor circumference

The following cases are classified as follows:

The classical case of 4 or 6 radial magnets magnetized along the circumference (e.g. CH217877, figures 2 and 3) is classified in H02K 1/2773. However, when only 2 magnets are present (CH217877 figure 1), classification is made in H02K 1/276.

Magnets mounted on a surface of any rotor (in case directly on the shaft), hollow or not, magnetic or not.

The following cases are classified as follows:

The classification of claw poles follows the following rules:

fastening between shaft and the rotor (parts): H02K 1/28

fastening between the rotor parts, e.g. the two parts carrying each half of the poles which form the rotor: H02K 1/243

Means for mounting or fastening cores with PM are classified:

any intermediate part or parts, including spiders, sleeves, resin moulded between magnetic part and shaft

Cooling channels (partially) in the shaft supporting the rotor magnetic core are also classified in this group, (together with the channels in the rotor magnetic core)

Cooling channels extending in a generally axial direction in the zone between the salient poles;

Cooling channels between poles of claw pole rotors.

Cooling channels between salient poles working as ventilators are only classified in H02K 1/325, but not systematically classified, not even as additional information, in H02K 9/06.

Details of the winding covering any aspect, e.g. electric aspects, mechanical aspects, cooling.

The slots are usually in a magnetic core;

Any winding with conductor transposed within a slot or between the slots e.g.:

The auxiliary windings are classified according to the main winding, i.e. if the main winding is in slots the additional winding is classified in H02K 3/16

Windings for all type of salient poles, including claw poles.

The auxiliary windings are classified according to the main winding, i.e. if the main winding is for salient poles the additional winding is classified in H02K 3/20

Any type of channel between conductors e.g. channels, openings, spaces between or around conductors in the active part of the conductor or in the winding heads.

Winding schemes.

Insulation sheets,

Insulation plates

Insulators are classified in this group only, when they have exclusively an insulation function; insulation elements having also a supporting function, e.g. a bobbin which is supporting the winding and isolating it from the core, are classified in H02K 3/46.

Fastening of windings arranged in the air gap (with or without a ferromagnetic back iron)

Supports shaped like air gap cans, but with the only function of supporting the winding are not classified in H02K 5/128.

Slot-closing devices, e.g. slot wedges.

Elements between salient poles but similar to slot wedges are classified in H02K 3/52 as invention information and, if relevant, classified in H02K 3/487 as additional information

When it is not clear, whether the machine has salient pole windings or not, the document is classified in H02K 3/50.

Connections from the winding ends till the bus rings included (supported in any way, on the stator, the casing etc.) H02K 3/505; leads between the bus rings and the external connections: H02K 5/225

When it is not clear, whether the machine has salient pole windings or not, the document is classified in H02K 3/50.

Fastening salient pole windings or connections thereto for annular cores with salient poles; the shape of the core can also be irregular and only generally annular, the air gap could be either radial or axial.

Fastening salient pole windings or connections thereto for U-shaped, E-shaped, I-shaped or similarly shaped cores.

Fastening salient pole for windings consisting of one ore more annular coils which are coaxial with the rotor axis.

The terminals of annular coils are classified: in H02K 3/525, if the structural association with the coil is relevant, and in H02K 5/225, if the connection arrangement with the casing is relevant.

Details of the bobbins including their connectors or wire guiding parts.

Means for supporting the casing and / or fixing it to an external support not covered by H02K 5/24, H02K 5/26 are classified in H02K 5/00.

Means for mounting or fastening, including vibration dampers, magnetic stationary parts are classified in:

Shafts with insulating parts are classified as invention in H02K 7/003 (details of the shafts) and as additional information in H02K 5/08.

Drain passages and venting, breathing or pressure compensating means are always tagged in H02K 2205/09

Electrical connections specific to submersible machine are classified in H02K 5/132 (as invention) and in H02K 5/225 (as additional information).

Brush holder supports

Elastically supported brush or brush holders, e.g. for avoiding noise / vibrations, are classified as invention in H02K 5/14 and as additional information in H02K 5/24. If however other relevant aspects of a casing specially adapted for avoiding noise / vibrations are present, the document should also be classified as invention in H02K 5/24.

Schematically described displaceable, e.g. rotatable, brush holder supports in DC commutator motors or generators having displaceable main or auxiliary brushes are only classified in H02K 23/18. Details interesting for brush holders in general are classified in H02K 5/14.

Means for keeping the brushes in a retracted position during assembly are always tagged in the group H02K 2205/06

Mounting arrangements e.g. details of the parts (of the electrical machine) supporting the bearing

Classification in H02K 5/16 versus H02K 7/08.

The document is classified in H02K 5/16 if the bearing is a "normal bearing" placed in the "normal position" and the invention deals with the means for supporting the bearing or with other aspects (e.g. cooling) of the area where the bearing is supported.

The document is classified in H02K 7/08 if the invention deals with the structural association of the bearing with the machine or some other element, e.g.:

bearings integrated with other elements or supported by elements usually having a different function;

bearings mounted in unusual positions or in a specific position in relation to other elements of the machine;

bearings having particular properties in relation to the machine (aspects of the bearing "per se" are however not classified in H02K, but in F16C);

a particular combination of bearings (with regard to e.g. their position, distance, materials, type, properties).

Elastically mounted bearings are classified as invention in H02K 5/16 and as additional information in H02K 5/24. If however other relevant aspects of a casing specially adapted for avoiding noise / vibrations are present, the document should also be classified as invention in H02K 5/24.

The lubrication aspects of the bearings are generally classified in H02K 5/16. If cooling is present, e.g. oil circulation for lubrication and cooling of the bearings the documents are classified as follows.

If the invention refers to details of the elements adjacent to the bearing, e.g. channels in the end shield bearing mounting area, the document is classified in H02K 5/16 as invention information and classified either as invention (if the cooling aspects are relevant per se) or as additional information in the most appropriate subgroup of H02K 9/00.

If the invention refers to a cooling/lubricating scheme without or with little physical details of the mounting area of the bearing, the document is classified in H02K 7/08 as invention information and as invention or as additional information in the most appropriate subgroup of H02K 9/00.

If a combination of the two cases mentioned above is present the document is classified in both H02K 5/16 and H02K 7/08.

If relevant details of the cooling channels are present the document should also be classified in e.g. H02K 1/20, H02K 1/32, H02K 5/20).

The subgroups of H02K 5/16 are subdivided according to the position of the bearings radially supporting the rotor (shaft).

Arrangements wherein the radial bearings are on both sides of the rotor, i.e. the rotor is supported between the bearings, are classified in H02K 5/161, H02K 5/1672, H02K 5/1732.

Arrangements wherein the radial bearings are on one side only of the rotor, i.e. the rotor is supported in a cantilevered position, are classified in H02K 5/163, H02K 5/1675, H02K 5/1735.

Arrangements wherein the rotor is supported about a fixed spindle or the rotor is supported directly are classified in H02K 5/165, H02K 5/1677, H02K 5/1737 (these last groups take precedence over the previous groups)

Sliding-contact bearings including fluid bearings, e.g. hydrostatic and hydrodynamic bearings

Structural association of a connection, connector, terminal or terminal box with the casing.

Electrical connections specific to submersible machine are classified in H02K 5/132 (as invention) and in H02K 5/225 (as additional information).

Connections arrangements associated with the housing are classified in H02K 5/225, other connections, e.g. the coil terminations on the magnetic core, are classified in H02K 3/50, H02K 3/52.

Connections from the winding ends till the bus rings included, supported in any way, on the stator, the casing etc., are classified in H02K 3/50, H02K 3/52, leads between the bus rings and the external connections are classified in H02K 5/225.

The terminals of annular coils are classified: in H02K 3/525, if the structural association with the coil is relevant, in H02K 5/225, if the connection arrangement with the casing is relevant.

Casings with vibration / acoustic dampening arrangements.

Means for mounting or fastening, including vibration dampers, magnetic stationary parts are classified in:

H02K 5/04 and in particular H02K 5/24, optionally classified as additional information in H02K 1/18 and subgroups, if these means are part of the casing.

Elastically supported brush or brush holders, e.g. for avoiding noise or vibrations, are classified as invention in H02K 5/14 and as additional information in H02K 5/24. Elastically mounted bearings are classified as invention in H02K 5/16 and as additional information in H02K 5/24. If, however, other relevant aspects of a casing specially adapted for avoiding noise / vibrations are present, the document is also classified as invention in H02K 5/24.

Every arrangement allowing a movement of the entire machine with respect to its support, its load, its driving motor e.g. the adjustable supports for moving the machine and tensioning the belt in an electric machine driven / driving via a pulley.

The adjustable supports for moving the machine and tensioning a belt of a pulley are only classified here and not in H02K 7/1004

The following arrangements are classified in H02K 7/00 (not in the subgroups):

Shafts with insulating parts are classified in H02K 7/003 (invention) and H02K 5/08 (additional information).

The structural association of an electric machine, often a motor-generator with any element, e.g. flywheel, shaft, connecting the main I.C. (internal combustion) engine to the wheels.

The structural association of an electric machine with a flywheel is classified:

The structural association of an electric machine with a flywheel is classified:

Flywheels for storing electrical energy as mechanical energy, e.g. rotary battery.

A flywheel is always a device for storing energy. The flywheels, in which the amount of energy is relatively limited and only used to smooth an oscillation / vibration or to add some inertia to a tool, are classified in H02K 7/02, while the flywheel in which electrical energy is stored as mechanical energy, e.g. rotary battery, are classified in H02K 7/025.

H02J concerns the complete system for energy storage (and its control), the structural aspects are covered by H02K 7/025, F16F 15/30.

Electrical linear actuators are classified in H02K 7/06, when the structural association with the electric motor is relevant. Actuators disclosed as "black box" in a more complex system, are only classified with the system application; actuators only relevant for the screw mechanism are only classified in F16H 25/20.

Similar devices driven by stepping motors can also be found in H02K 37/24

Electric linear actuators comprising an electric motor rotor structurally associated with a screw mechanism are classified in H02K 7/06.

Machines producing vibrations by any sort of unbalance e.g. static unbalance, dynamic unbalance, eccentric bearings, eccentric forces.

Machines using as unbalanced masses elements of the machine itself, e.g. eccentric rotors, shafts or windings.

Electromechanical oscillators as US3585424 or US3355645.

Particular position or size or properties of the bearing in relation to the machine.

Classification in H02K 5/16 versus H02K 7/08.

The document is classified in H02K 5/16 if the bearing is a "normal bearing" placed in the "normal position" and the invention deals with the means for supporting the bearing or with other aspects (e.g. cooling) of the area where the bearing is supported.

The document is classified in H02K 7/08 if the invention deals with the structural association of the bearing with the machine or some other element, e.g.:

bearings integrated with other elements or supported by elements usually having a different function;

bearings mounted in unusual positions or in a specific position in relation to other elements of the machine;

bearings having particular properties in relation to the machine (aspects of the bearing "per se" are however not classified in H02K, but in F16C);

a particular combination of bearings (with regard to e.g. their position, distance, materials, type, properties).

The lubrication aspects of the bearings are generally classified in H02K 5/16. If cooling is present and the invention refers to a cooling/lubricating scheme without or with little physical details of the mounting area of the bearing, the document is classified in H02K 7/08 as invention information and as invention or as additional information in the most appropriate subgroup of H02K 9/00.

The subgroups H02K 7/083 - H02K 7/086 are subdivided according to the position of the bearings radially supporting the rotor (shaft).

Arrangements wherein the radial bearings are on both sides of the rotor, i.e. the rotor is supported between the bearings, are classified in H02K 7/083;

Arrangements wherein the radial bearings are on one side only of the rotor, i.e. the rotor is supported in a cantilevered position, are classified in H02K 7/085;

Arrangements wherein the rotor is supported about a fixed spindle or in which the rotor is directly supported are classified in H02K 7/086 (this last group take precedence over the previous groups).

Magnetic bearings are classified in H02K 7/09 (i.e. H02K 7/09 takes precedence over the subgroups H02K 7/083 - H02K 7/086).

Particular cases.

If the main bearing is a magnetic bearing combined with a non-magnetic backup bearing, classify in H02K 7/09 as invention information and,

if the backup bearings are only relevant in combination with the magnetic bearing, in the corresponding H02K 7/08 subgroup as additional information;

if the backup bearing are also relevant per se, in the corresponding H02K 7/08 subgroup (and if relevant in H02K 5/16 subgroups) as invention information.

If the main bearing is non-magnetic bearing with a secondary magnetic bearing effect (e.g. a biasing effect), classify as invention information in H02K 7/08 or H02K 5/16 subgroups and as additional information in H02K 7/09.

Bearing arrangements specially adapted to worm-wheel or worm-nut drive, e.g. bearing arrangements allowing axial movement of the rotor in the bearing system, needed because of the interaction with the gears, or biasing the rotor in a specific axial position.

H02K 7/081 takes precedence over H02K 7/1166

Magnetic bearings are classified in H02K 7/09 (i.e. H02K 7/09 takes precedence over the subgroups H02K 7/083 - H02K 7/086).

Particular cases.

If the main bearing is a magnetic bearing combined with a non-magnetic backup bearing, classify in H02K 7/09 as invention information and,

If the main bearing is non-magnetic bearing with a secondary magnetic bearing effect (e.g. a biasing effect), classify as invention information in H02K 7/08 or H02K 5/16 subgroups and as additional information in H02K 7/09.

Group H02K 7/12 takes precedence over groups H02K 7/102 - H02K 7/118

Brakes or clutches with teeth or similar members engaging corresponding notches (e.g. mechanical locks acting by interference and not by friction) are classified in H02K 7/10, not in the subgroups covering friction brakes or clutches

Pulleys or similar devices (e.g. drums)

Pulleys directly attached, integrated with, or mounted to the rotor.

Machines, with inner or outer rotor, positioned inside the pulley

Pulleys directly mounted on the outer surface of an outer motor rotor.

The tubular motors in which the motor drives a cylinder arranged around the motor, e.g. rolls for conveyor belts, are also classified together with the pulley in H02K 7/1012.

Brakes using annular electromagnets with axial air-gap acting along the machine axis, including array of several electromagnets generally annularly arranged.

Brakes actuated by magnetic field derived by the motor magnetic field by means of e.g. flux deflectors.

Brakes activated by stray fields acting on the brake "armature" in an area close to the stator/rotor magnetic core axial ends

The brake element that must be close to a motor/generator frontal area is the brake armature and not the braking pad support, which very often coincides with the armature.

Structural association with separate dynamo-electric brakes, including permanent magnets for locking the rotor in a predetermined position.

Structural adaptation of a motor / generator in order to brake it (or locking it at still stand) by electrodynamic forces e.g. generated by using the machine main windings and magnetic circuit.

Electric actuators of this type can be found in several application fields. Said actuators are classified in H02K 7/1166, when the structural association with the electric motor is relevant. Actuators disclosed as "black box" in a more complex system, should only be classified with the system application; actuators only relevant for the screw mechanism should be only classified in F16H.

Mechanical starting devices e.g.:

Starting devices comprising clutches or devices which allow a partial free rotation of the rotor (from the load) are classified in H02K 7/118 (without reversing means) and in H02K 7/1185 (with reversing means).

Starting devices comprising means for blocking the rotation of the rotor when started in the "wrong" direction and reversing said rotation (often, but not necessarily including clutches or devices which allow a partial free rotation of the rotor from the load).

Starting devices comprising clutches or devices which allow a partial free rotation of the rotor (from the load) are classified in H02K 7/118 (without reversing means) and in H02K 7/1185 (with reversing means).

H02K 7/12 is used as invention information only for cases covered by H02K 7/10 (structural association with clutches, brakes, gears, pulleys, mechanical starters). If this is not the case, the document is classified in H02K 7/12 as additional information only and classified as invention in the most appropriate group, e.g. H02K 7/00. In particular means for mechanical adjustment of the flux in PM synchronous machines are only classified H02K 21/021.

If the driving-load aspect predominates, see the relevant subclass.

Relevant aspects of a motor, concerning the structurally association with a driven load are classified in H02K 7/14. On the contrary machines described as a black box should be only classified in the application field.

The tubular motors in which the motor drives a cylinder arranged around the motor, e.g. rolls for conveyor belts, are classified together with the pulleys in H02K 7/1012.

Machines with shafts, bearing, rotors etc. specially modified for operation at high speed (problems with oscillation at critical speeds)

If the driving-motor aspect predominates, see the relevant subclass, e.g. F03B 13/00 for turbines. Relevant aspects of a generator, concerning the structurally association with a driving motor are classified in H02K 7/18. On the contrary machines described as a black box should be only classified in the corresponding application field.

The only aspects of gensets (generating set driven by a piston I.C. engine), which are classified in H02K 7/1815, are the ones relating to the adaptation of the generator. All other aspects, e.g. general aspects, of gensets are classified in F02B 63/04.

The structural association of an electric machine with a flywheel is classified:

Rotary generators driven by any turbine like machine e.g.

Documents concerning a generator for wind generators are classified in H02K 7/183 or H02K 7/1838.

Generators described as "black box" in a wind turbine are classified only in F03D 9/25. Documents are classified in H02K, when relevant aspects, e.g. electrical, magnetic, thermal, structural, of the generator are present. When classified in H02K 7/183 or H02K 7/1838 the documents are classified as:

invention, in case of structural association between generator and wind turbine, i.e. shared components; general structure of the generator specifically adapted to the use in a wind turbine,

additional information, if a clear structural association is not present (please note that even if the use in a wind turbine is just hinted a class as additional information is given).

In any case specific aspects of the generator, e.g. cooling channels, windings, cores, are classified in the respective H02K subgroups.

A bearing common to the blade rotor and the generator rotor is only classified in F03D 9/25 if the blade rotor aspects are clearly predominant, i.e. it is essentially the same bearing that would be used to support the blade rotor.

Generators structurally associated with prime motors that intrinsically deliver power to the generators in a non continuous way, .e.g.:

Generators continuously driven by animals (including humans) or vehicles, e.g.:

the sectional generators structurally associated with a wind turbine;

non-reciprocating linear generators, e.g. continuously moving on a rail (like a train).

The following generators are specifically classified in H02K 7/1869:

the sectional generators structurally associated with a wind turbine,

non-reciprocating linear generators, e.g. continuously moving on a rail (like a train)

Sectional generators structurally associated with a wind turbine, are classified:

in F03D only, if schematically described / if described as a black box;

in H02K 7/1869 (and possibly F03D), if described with some relevant detail of the generator.

The pistons must be "free pistons", i.e. not connected to a rotary shaft, of an engine (moved by a fluid inside the cylinder). The free pistons could also be linked one to another and could even consist of membranes.

In H02K 9/00 subgroups, documents often contain, explicitly or implicitly, aspects of a plurality of cooling means, which are covered by different subgroups.

As a general rule all the relevant aspects of said cooling means should be classified either as invention (if interesting also per se) or as additional information (if only interesting in combination with aspects covered by other subgroups). Aspects which are not relevant should however not be classified.

For example:

Cooling by using compressed air (in an open circuit) should be classified in this group

Cooling systems in which ambient air flows through the machine, having means for generating flow of cooling medium, consisting of i.e.

For the classification of documents containing aspects of a plurality of cooling means covered by different subgroups see special classification rules of H02K 9/00.

For the classification of documents containing aspects of a plurality of cooling means covered by different subgroups see special classification rules of H02K 9/00.

Conventional definition of the casing boundaries.

When classifying in the subgroups H02K 9/08 - H02K 9/18, in order to decide whether a gaseous cooling medium circulates inside/outside the casing, it is necessary to define where the boundaries of the casing are.

Since this is not always evident (because often the casing consists of additional elements, e.g. channels, assembled around the basic casing), for the purpose of classifying in all said groups, the casing is considered to be conventionally limited:

Please note that in simple machines said conventional boundaries coincide with the real casing).

Example of classification (only the cooling closed circuits inside the machine, e.g. passing through the winding heads 4, are considered).

For the classification of documents containing aspects of a plurality of cooling means covered by different subgroups see special classification rules of H02K 9/00.

For the conventional definition of the casing boundaries see classification rules of H02K 9/08.

Example of systems classified in H02K 9/10:

Cooling systems in which a gaseous cooling medium flows in closed circuit, a part of which is external to the machine casing, wherein there are no means, inside the machine casing, for generating flow of cooling medium

For the conventional definition of the casing boundaries see classification rules of H02K 9/08.

Cooling systems in which gaseous cooling medium circulates:

For the classification of documents containing aspects of a plurality of cooling means covered by different subgroups see special classification rules of H02K 9/00.

Any system in which cooling gaseous medium cools the machine by cooling the outside of the machine casing, with or without a surrounding mantle, is classified in this group, including systems in which the fluid circulates in ducts built in the thickness of the casing wall.

Systems wherein the fluid circulates in ducts built inside the conventional casing boundaries are classified in H02K 9/16 (for the conventional definition of the casing boundaries see classification rules of H02K 9/08).

Classification examples:

In order to be classified in H02K 9/16 the fluid must circulate in ducts built inside the conventional casing boundaries (for the conventional definition of the casing boundaries see classification rules of H02K 9/08). In systems classified in H02K 9/16 the "ducts within the casing" can at least in part coincide with cooling ducts in the stator laminations, see e.g. US5780946, fig. 1, 2.

Systems in which the fluid circulates in ducts built in the thickness of the casing walls are classified in H02K 9/14.

Cooling system in which (all these conditions must be fulfilled):

Consequently to the definition, if the heat exchanger is cooled:

the system is not classified in H02K 9/18, but in H02K 9/10, H02K 9/12 instead.

Machines with closed circuit liquid cooling;

Machine with any other form of liquid cooling.

For the classification of documents containing aspects of a plurality of cooling means covered by different subgroups see special classification rules of H02K 9/00.

Openings, ducts, and other arrangements for providing the cooling medium.

e.g. Machines with air gap sleeves or similar devices to provide for different cooling media

Cooling system in which the medium vaporises within the casing;

Heat pipes

Heat bridges

Heat sinks and other radiating means

For the classification of documents containing aspects of a plurality of cooling means covered by different subgroups see special classification rules of H02K 9/00.

Passive solid heat conducting materials creating a path of least resistance for heat transfer between the stator or the rotor and another solid material.

Vessels (e.g. pipes) containing a medium undergoing a phase transition and transferring heat between a first interface of the vessel in contact with the stator or the rotor and a second interface of the vessel in contact with a cooling medium (e.g. air, a liquid or a solid).

Passive solid heat conducting materials in thermal contact with the stator or the rotor and transferring heat to a fluid medium (e.g. air or a liquid coolant).

Safety devices;

Devices for rinsing the machine from H2 to avoid explosions.

Structural association

Casing and cooling aspects only relevant for details covered by H02K 11/00, e.g. the casing / cooling of the electronics, are in general only classified in H02K 11/00 and not in H02K 5/00 and H02K 9/00, unless they are also relevant for the machine in general.

When the electronics covered by H02K 11/00 is the only invention information and the machine to which the electronics is mounted does not have other relevant aspects the documents are in general classified (according to the special rules of classification within the subclass):

as invention information in H02K 11/00 or subgroups,

as additional information in the class of the type of machine, e.g. H02K 7/1166

Structural association with e.g. transformers, batteries, fuel cells, lamps, resistors, capacitors.

Shielding by any means, e.g. screens or coils.

Suppressing RFI [radio frequency interference] or EMI [electromagnetic interference].

If the suppressor is clearly associated (explicitly or even implicitly) with spark suppression, it is classified in H02K 13/105 (only), otherwise in H02K 11/028.

Devices for measuring distances or positions other that the position of the rotor in the rotary direction, e.g. measuring the air gap while the machine is operating.

In this group, both the detectors and the detected elements are classified.

Position or speed sensors used for commutating brushless machines are classified in H02K 29/06 - H02K 29/14 even if they are additionally used for measuring position or speed for other purposes, i.e. this type of sensors is in general not classified in H02K 11/21 and subgroups.

RF-chips are classified in H02K 11/21 (not in the subgroups)

Using separate detecting coils;

Using the machine windings also as detecting coils (i.e. sensorless position control).

Sensorless arrangements are classified in this group, when the coils or other parts of the machine, e.g. the rotor, are specifically adapted to the function of sensing speed or position.

Fuses responding (melting) to a current passing through the fuse

Control circuits in general with or without PCB

Control circuits comprising power electronics

Devices

Control circuits, with or without power electronics, associated with small gear motors of the worm and wheel type, e.g. of the type used in windshield wipers

Simple grounding of casing are additionally classified in H02K 5/225.

The structural association of brushes, brush holders, commutators or collectors (slip rings) with the electric machine is classified in H02K 13/00 or H02K 5/14.

On the contrary the following is classified in H01R 39/00:

specific details of brushes or commutators / collectors per se;

aspects relating to the interaction brush-collector / commutator.

Arrangements for improving commutation, which are structurally associated with the electric machine

If the suppressor is clearly associated (explicitly or even implicitly) with spark suppression it is classified in H02K 13/105 (only), otherwise in H02K 11/028.

Every method or apparatus specially adapted for the manufacturing, assembling, maintaining or repairing dynamo-electric machines.

Documents referring to manufacturing methods are classified in H02K 15/00 and subgroups only if they disclose "real" methods, i.e. disclose relevant information about the manufacturing aspects. Documents describing or formally claiming a method, which in fact only consists in the reformulation of a product claim, without any relevant manufacturing information, are NOT classified in H02K 15/00.

In general measuring electric properties on dynamoelectric machines is classified only in G01R 31/34 and not in H02K, however:

the structural association of a dynamo-electric machine with measuring devices which are constantly mounted in the machine are classified: in H02K 11/00, H02K 17/30, H02K 19/36, H02K 23/66, H02K 27/28

the structural association with devices which are temporarily mounted to the machine during tests / manufacturing, etc. is classified in H02K 15/00 or in its specific subgroups.

Methods or apparatus not specific to a process covered by a subgroup, e.g. cleaning in general moving, transporting, storing of electric machines or components thereof (including production lines and pallets) between different working stations are classified in H02K 15/00

Methods to obtain a type of machine, e.g. a permanent magnet alternator, by modifying another type of machine, e.g. an asynchronous motor, are classified as invention in H02K 15/0006 and in the group of the obtained machine and as additional information in the group of the original machine.

Binding the winding heads

Method or apparatus for manufacturing terminals or leads.

Helically wound cores

Inserting the prefabricated windings in the machine, usually in a magnetic core;

Moulding metallic powders around the windings.

Here are classified documents describing inserting methods specially adapted for large windings, usually consisting of large bars. In case of doubt or when the method can also be used for smaller winding the documents are classified here and in the other relevant groups.

Windings inserted perpendicularly to the axis of the slots or inter-polar channels, e.g. in the radial direction when considering a machine with radial air-gap

There can be a component in an other direction (e.g. along a slot), but the winding is inserted mainly in the direction indicated in the title.

Windings inserted parallelly to the axis of the slots or inter-polar channels, e.g. in the axial direction when considering a machine with radial air-gap

There can be a component in an other direction (e.g. perpendicular to the slot), but the winding is inserted mainly in the direction indicated in the title.

Windings inserted by means of a "stripper" inserter (e.g. US4750258).

Group H02K 16/00 takes precedence over groups H02K 17/00 - H02K 53/00, unless otherwise explicitly indicated in the references relevant to classification valid for this group and its subgroups.

Machines classified in H02K 16/00 as invention information should have at least the casing in common; a plurality of associated independent electric machines (e.g. a single gear box driving several independent electric generators attached to it), if the structural association among the machines is relevant, are classified in H02K 16/00 as additional information only.

Machines classified as invention in H02K 16/00 and consisting of the combination of two or more "elementary" machines of the type covered in groups H02K 17/00- H02K 99/00 should also be classified, usually as additional information (as invention if interesting per se), in the groups of said "elementary" machines.

Modular electric machines or machines with redundant armature windings should at least be classified as additional information.

The following types of documents are NOT classified in this group (unless they are specially adapted in order to be modular machines):

a plurality of identical stators/rotors units, disposed along the rotor axis and shifted to form the phases of a multi-phase machine,

axial air-gap machines consisting of a plurality of identical stator/rotor units fixed to the same shaft.

It is not very clear if two separate windings on a rotor/ stator should be considered as two rotors/stators; as a consequence many documents that could be classified in a subgroup are in fact classified in the top group H02K 16/00.

Machines with rotating "stators", i.e. armature and field counter-rotating.

The movement of the "stators" must be substantial, e.g. stators only adjustable but essentially fixed are not classified in H02K 16/005

The rotating "stator" can be blocked in certain circumstances (e.g. by a brake)

Machines in which a fixed stator drives a rotor which is mechanically connected with a moving "stator" which drives another rotor.

References / special rules are present for some of the subgroups (see the specific subgroup)

Synchronous motors with additional short-circuit winding are classified in H02K 19/14 or H02K 21/46

Asynchronous motors with additional means for synchronization (e.g. means for generating a rotor synchronous field by injecting in the rotor short-circuit winding a DC current, see e.g. WO2004079879; additional synchronizing electromagnetic devices, see GB2052885) are classified in H02K 17/26

In case of doubt classify in both subgroups

Documents characterised by the arrangement of exciting windings or exciting systems in general.

Synchronous motors with additional short-circuit winding are classified in H02K 19/14 or H02K 21/46

Asynchronous motors with additional means for synchronization (e.g. means for generating a rotor synchronous field by injecting in the rotor short-circuit winding a DC current, see e.g. WO2004079879; additional synchronizing electromagnetic devices, see GB2052885) are classified in H02K 17/26

In case of doubt classify in both subgroups

Documents characterised by the arrangement of exciting windings or exciting systems in general.

Schemes with rectifiers

PM machines in which the excitation flux (i.e. field) is regulated:

are classified in H02K 21/02 (not in the subgroups)

PM synchronous motors or generators in which the excitation flux (i.e. field) acting on the windings is regulated by mechanical means i.e. by moving some parts of the magnetic core of the machine in order to change the amount of excitation flux which interacts with said windings, e.g. by partially extracting the PM rotor from the stator)

Means for mechanical adjustment of the flux in PM (permanent magnets) synchronous machines are not classified in H02K 7/12.

Similar means for mechanical adjustment of the flux in machines which are NOT PM synchronous motors or generators (e.g. asynchronous machines, synchronous machine with wound field, PM coupling as classified in H02K 49/10) are not classified as invention in H02K 21/021, they are however classified in this group as additional information.

Machines in which the amount of excitation flux acting on the windings is controlled:

Machines in which the amount of excitation flux acting on the windings is controlled by varying the overlap, across the air gap, between rotor and stator surfaces, e.g. by relatively moving said rotor and / or stator in a direction perpendicular to the thickness of the air gap.

Radial air gap machine machines regulated by axially extracting the rotor from the stator or vice versa

Machines in which the amount of excitation flux acting on the winding is controlled by varying the thickness of the air gap, i.e. by moving rotor and stator closer or further apart.

Machines with a conical air gap, in which a conical rotor is axially translated with respect to a conical stator.

Machines in which the modification of the excitation flux is obtained by:

Overhanging poles or magnets, i.e. machines with rotor and stator positioned essentially side by side along the machine axis, one of the two members having polar elements extending inside or outside the other member.

Overhanging poles or magnets, i.e. machines with rotor and stator positioned essentially side by side along the machine axis, one of the two members having polar elements extending inside or outside the other member, as in GB2083953, are classified in H02K 21/12 not in the subgroups.

Transversal flux machines with annular armature coils which are coaxial with the rotor axis.

Transversal flux machines with annular armature coils which are coaxial with the rotor axis

Vehicle generators with a pot-shaped rotor used as a flywheel

The machines are classified according to the shape of the main stator core

Machines in this group, which often comprise a plurality of armature cores, are not be classified in H02K 21/48.

Machines with armature and magnets both on the same stationary member, the other member being the rotary flux distributor

Synchronous motors with additional short-circuit winding are classified in H02K 19/14 or H02K 21/46

Asynchronous motors with additional means for synchronization (e.g. means for generating a rotor synchronous field by injecting in the rotor short-circuit winding a DC current, see e.g. WO2004079879; additional synchronizing electromagnetic devices, see GB2052885) are classified in H02K 17/26

In case of doubt classify in both subgroups

Generic universal motors are normally classified together with the DC motors in the relevant H02K 23/00 subgroup, i.e. they are not systematically classified in H02K 23/64.

Armature schemes, e.g. layout of windings and / or of connections with commutator blades

only specific adaptation for running under DC/AC by choice, e.g. switches to select a particular circuit

Synchros, selsyns and resolvers and other similar devices working in the same ways, i.e. generating and sensing sinusoidal voltages/currents whose phase and amplitude is related to the rotor position. These machines can be used to measure an angle or to transmit the angle to a similar machine.

Machines with mechanical interrupters.

A rule of the thumb to discriminate between electromagnets with movable armature (H01F 7/08) or even rotary armature (H01F 7/145) and torque motors (H02K 26/00) is to consider the action of the magnetic field in the air gap:

electromagnets (H01F 7/08) act by closing the air gap (when the armature is attracted by the coil system);

electric motors (H02K 26/00) orient stator and rotor structures, without closing the air gap (as in a normal rotary dynamoelectric machine).

Spherical motors are classified:

Commutator machines having an armature connected to a commutator (like the machines of H02K 23/00) and a stator typical of an AC machine, e.g. an asynchronous motor.

These machines are inherently synchronous machines with an electronic control; structural aspects not specifically covered by H02K 29/00 and subgroups are classified in the groups for the corresponding synchronous machines, e.g. H02K 21/00 for PM synchronous machines.

If just details of the stator or of the rotor, winding etc. are involved the document can be classified as invention in the relevant detail group (e.g. H02K 1/27) and as additional information in H02K 29/03.

Position sensing devices for commutation purposes

In this group are not classified normal position sensing devices (of the type classified H02K 29/06 - H02K 29/12) from which a speed indication can be in principle derived by processing of the sensor position signal. It is also noted that the aspects of signal processing are covered by H02P.

Motors in which the mover/rotor can assume only a limited number of positions (usually two) between which the mover/rotor uninterruptedly reciprocates (e.g. vibrating motors).