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CONTROLLING COMBUSTION ENGINES (cyclically operating valves for combustion engines F01L; controlling combustion engine lubrication F01M; cooling internal combustion engines F01P; supplying combustion engines with combustible mixtures or constituents thereof, e.g. carburettors, injection pumps F02M; starting of combustion engines F02N; controlling of ignition F02P; controlling gas-turbine plants, jet-propulsion plants, or combustion-product engine plants, see the relevant subclasses for these plants)
Informative references
Attention is drawn to the following places, which may be of interest for search:
Automatic controllers for prime movers, in general
Glossary of terms
In this subclass/group, the following terms (or expressions) are used with the meaning indicated:
Engine
"engine" means a device for continuously converting fluid energy into mechanical power. Thus, this term includes, for example, internal-combustion piston engines, but it excludes single-stroke devices
Controlling fuel-injection pumps, e.g. of high pressure injection type (F02D 3/00 takes precedence; controlling fuel-injection electrically F02D 41/30) [N: pumping elements on fuel pressure acting for varying fuel delivery in quantity or timing F02M ]
Definition statement
This subclass/group covers:

Controlling fuel-injection pumps, e.g. of the high pressure injection type and pertains in particular to mechanical controlling and linkage of mechanically controlled fuel injection pumps.

References relevant to classification in this group
This subclass/group does not cover:
Controlling low-pressure fuel injection by means other than controlling only an injection pump

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

Peculiar to engines characterised by their use of non-liquid fuels, pluralities of fuels, or non-fuel substances added to the combustible mixtures
Peculiar to supercharged engines
Informative references
Attention is drawn to the following places, which may be of interest for search:
Cyclically operating valves for combustion engines
Controlling combustion engine lubrication
Cooling internal combustion engines
Controlling combustion engines
Controlling pumps peculiar to engines characterised by their use of non-liquid fuels, pluralities of fuels, or non-fuel substances added to the combustible mixtures
Controlling supercharged engines
Controlling fuel-injection electrically
Supplying combustion engines with combustible mixtures or constituents thereof, e.g. carburettors, injection pumps
Control of modern common rail fuel pumps
Starting of combustion engines
Controlling of ignition
Automatic controllers for prime movers, in general
Controlling gas-turbine plants, jet-propulsion plants, or combustion-product engine plants
see the relevant subclasses for these plants.
[N: by mechanical means dependent on engine speed for angular adjustment of driving and driven shafts]
Definition statement
This subclass/group covers:

E.g. using a centrifugal governor to adjust the angular timing of pump shaft.

[N: hydraulic]
Definition statement
This subclass/group covers:

Hydraulic adjustment of injection timing. E.g. using a hydraulic phase shifter device between pump and pump drive or angularly adjusting a cam profile to adjust the timing.

Controlling low-pressure fuel injection, i.e. where the air-fuel mixture containing fuel thus injected will be substantially compressed by the compression stroke of the engine, by means other than controlling only an injection pump (controlling fuel-injection electrically F02D 41/30; [N: controlling the feeding of liquid fuel from storage containers to carburettors or fuel-injection apparatus F02D 33/003;]carburettors F02M)
References relevant to classification in this group
This subclass/group does not cover:
Controlling fuel-injection electrically
Controlling, e.g. regulating, fuel injection peculiar to engines characterised by their use of non-liquid fuels, pluralities of fuels, or non-fuel substances added to the combustible mixtures
Carburettors

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

Peculiar to engines characterised by their use of non-liquid fuels, pluralities of fuels, or non-fuel substances added to the combustible mixtures
Peculiar to supercharged engines
Informative references
Attention is drawn to the following places, which may be of interest for search:
Cyclically operating valves for combustion engines
Controlling combustion engine lubrication
Cooling internal combustion engines
Controlling supercharged engines
Supplying combustion engines with combustible mixtures or constituents thereof, e.g. carburettors, injection pumps
Low pressure fuel-injection apparatus
Starting of combustion engines
Controlling of ignition
Other fuel-injection control
References relevant to classification in this group
This subclass/group does not cover:
Electric fuel-injection control
Control of fuel injection peculiar to engines characterised by their use of non-liquid fuels, pluralities of fuels, or non-fuel substances added to the combustible mixtures
Control of supercharged engines

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

Peculiar to engines characterised by their use of non-liquid fuels, pluralities of fuels, or non-fuel substances added to the combustible mixtures
Peculiar to supercharged engines
Informative references
Attention is drawn to the following places, which may be of interest for search:
Automatic controllers for prime movers, in general
Cyclically operating valves for combustion engines
Controlling combustion engine lubrication
Cooling internal combustion engines
Supplying combustion engines with combustible mixtures or constituents thereof, e.g. carburettors, injection pumps
Starting of combustion engines
Controlling of ignition
Controlling fuel injection where fuel is injected by compressed air
Informative references
Attention is drawn to the following places, which may be of interest for search:
Apparatus for injecting fuel by means of high pressure gas
Apparatus for low pressure fuel injection by compressed air
Controlling engines by throttling air or fuel-and-air induction conduits or exhaust conduits
Definition statement
This subclass/group covers:

Valves for controlling the air or air and fuel admission into or the exhaust out of the engine and the arrangement of such valves in intake or exhaust conduits.

Relationship between large subject matter areas

General aspects of valves can be found in F16K

References relevant to classification in this group
This subclass/group does not cover:
Lift valves
EGR valves
Lift valves in general
Informative references
Attention is drawn to the following places, which may be of interest for search:
Valves in general
Glossary of terms
In this subclass/group, the following terms (or expressions) are used with the meaning indicated:
Pivotally-mounted flaps
Flaps rotating around an axis
Synonyms and Keywords

In patent documents the following expressions/words "butterfly valve" and "pivotally-mounted flap valve" are often used as synonyms.

Arrangements for, or adaptations to, non-automatic engine control initiation means, e.g. operator initiated (specially for reversing F02D 27/00; arrangement or mounting of prime-mover control devices in vehicles B60K 26/00 )
Definition statement
This subclass/group covers:

Hand- and/or foot pedal operated engine control initiation means and control linkages between the hand and/or foot pedal and the controlled device, e.g. throttle valve, carburettor or fuel injector. The control linkage can be mechanical, e.g. combined with power drive assistance, or non-mechanical, e.g. hydraulic linkage e.g. combined with power drive assistance.

Relationship between large subject matter areas

Electronic engine control in general, F02D

References relevant to classification in this group
This subclass/group does not cover:
Arrangement or mounting of prime-mover control devices in vehicles
Electronic engine control initiation means
Engine control initiation means for reversing
Informative references
Attention is drawn to the following places, which may be of interest for search:
Arrangements or mounting of propulsion unit control devices in vehicles
Controlling members, e.g. knobs or handles; assemblies or arrangements thereof;
Glossary of terms
In this subclass/group, the following terms (or expressions) are used with the meaning indicated:
Power drive assistance
Drive assistance for hand or foot
Synonyms and Keywords

In patent documents the following expressions/words "prime mover" and "engine" are often used as synonyms.

of the electric type
Definition statement
This subclass/group covers:

Mechanical aspects/construction of electric throttles; Links between throttle and pedal as long as it concerns the electrical aspects, or the mechanical linking of the motor to the rest, e.g. clutch etc.

characterised by the function linking demand to actuation
Definition statement
This subclass/group covers:

Throttles characterised by the function of linking demand to actuation using:

- Different response curves between pedal and throttle, combination of pedal (or cable) displacement and motor movement, free gaps

- Torque control, i.e. conversion accelerator position -> torque demands -> actuator commands

Detection of demand or actuation
Definition statement
This subclass/group covers:

Detection of throttle position or accelerator position

Informative references
Attention is drawn to the following places, which may be of interest for search:
Sensors to detect relative movements
Pedal position sensors
Controlling the engine output power by varying inlet or exhaust valve operating characteristics, e.g. timing (modifying valve gear F01L)
Definition statement
This subclass/group covers:

Controlling the engine output power by varying inlet or exhaust valve operating characteristics, e.g. timing. The inlet and exhaust valves within an internal combustion engine are used to control the flow of the intake and exhaust gases into and out of the combustion chamber. The timing, duration and lift of these valve has a significant impact on engine performance. In a standard engine, the valve events are fixed, so performance at different loads and speeds is always a compromise between driveability, e.g. power and torque, fuel economy and emissions. An engine equipped with a variable valve actuation system is freed from this constraint, allowing performance to be improved over the engine operating range.

Relationship between large subject matter areas

Valve-gear or valve arrangements: F01L

Electronic engine control in general: F02D

References relevant to classification in this group
This subclass/group does not cover:
Modifications of valve gear
Electrical control of supply of combustible mixtures
Informative references
Attention is drawn to the following places, which may be of interest for search:
Modifications of valve gear
Electrical control of supply of combustible mixtures
Glossary of terms
In this subclass/group, the following terms (or expressions) are used with the meaning indicated:
Miller-Atkinson cycle
Combustion cycle characterised by extending the stroke and raising the expansion and compression ratio. Premature detonation is overcome by using valve timing variations to make the effective compression and expansion strokes asymmetrical.
Synonyms and Keywords

In patent documents the following abbreviations are often used:

VVT
Variable valve timing
SOHC
Single overhead camshaft
DOHC
Double overhead camshaft
EGR
Exhaust gas recirculation
Varying compression ratio (modifying valve gear F01L)
Definition statement
This subclass/group covers:

Varying compression ratio to adjust internal combustion engine cylinder compression ratios. For automotive use this needs to be done dynamically in response to the load and driving demands. Higher loads require lower ratios to be more efficient and vice versa. Variable compression engines allow for the volume above the piston at TDC to be changed.

Relationship between large subject matter areas

Other engines, F02B 75/00; varying inlet or exhaust valve operating characteristics, F02D 13/00; electrical control of supply of combustible mixtures, F02D 41/00.

References relevant to classification in this group
This subclass/group does not cover:
Means for creating variable distances between pistons at top dead-centre positions and cylinder heads.
Modifying valve gear
Informative references
Attention is drawn to the following places, which may be of interest for search:
Engines with variable distances between pistons at top dead-centre positions and cylinder heads.
Glossary of terms
In this subclass/group, the following terms (or expressions) are used with the meaning indicated:
TDC
Top Dead Centre
Controlling engines by cutting out individual cylinders; Rendering engines inoperative or idling (controlling or rendering inoperative by varying inlet or exhaust valve operating characteristics F02D 13/00 )
Definition statement
This subclass/group covers:

Controlling engines by cutting out individual cylinders; Rendering engines inoperative or idling. Cylinder deactivation is used to reduce the fuel consumption and emissions of an internal combustion engine during light-load operation. In typical light-load driving the driver uses only around 30 percent of an engine’s maximum power. In these conditions the throttle valve is nearly closed and the engine needs to work to draw air. This causes an inefficiency known as pumping loss. Some large capacity engines need to be throttled so much at light load that the cylinder pressure at top dead centre is approximately half that of a small 4-cylinder engine. Low cylinder pressure means low fuel efficiency. The use of cylinder deactivation at light load means there are fewer cylinders drawing air from the intake manifold, which works to increase its air pressure. Operation without variable displacement is wasteful because fuel is continuously pumped into each cylinder and combusted even though maximum performance is not required.

Relationship between large subject matter areas

Control systems for hybrid vehicles: B60W 20/00;

Controlling engines driving vehicles: F02D 29/00;

Starting engines: F02N 11/00.

References relevant to classification in this group
This subclass/group does not cover:
Cutting out cylinders by varying inlet or outlet valve operating characteristics
Rendering engine inoperative or idling by varying inlet or outlet valve operating characteristics
Informative references
Attention is drawn to the following places, which may be of interest for search:
Engines with air storage chambers
Piston pumps for charging
Varying inlet or exhaust valve operating characteristics
Controlling engines characterized by their use of non-liquid fuels, pluralities of fuels, or non-fuel substances added to the combustible mixtures (the non-fuel substances being gaseous F02D 21/00 )
Definition statement
This subclass/group covers:

Mechanical and control aspects of engines using gaseous fuels, solid fuels or a combination of gaseous and non gaseous fuels. The latter simultaneously or non simultaneously used. Important aspects of the group are: configuration and control of the fuel supply system, special operating modes depending on the type of fuel and measuring and estimating of the fuel and engine parameters.

Relationship between large subject matter areas

Control of engines using non-liquid fuels, F02D 41/0025

References relevant to classification in this group
This subclass/group does not cover:
Electronic control of engines using non-liquid fuels
Controlling engines being supplied with gaseous non-fuel substances
Informative references
Attention is drawn to the following places, which may be of interest for search:
Apparatus for supplying engines with gaseous fuels
Engines characterised by operating on gaseous fuels
Glossary of terms
In this subclass/group, the following terms (or expressions) are used with the meaning indicated:
Non-fuel gas
Oxygen, exhaust gas etc.
Controlling engines characterized by their being supplied with non-airborne oxygen or other non-fuel gas
Definition statement
This subclass/group covers:

Control systems in which oxygen or secondary air and/or exhaust or other non-fuel gases are being fed to the engine in order to increase the engine output power and/or to clean the exhaust gases.

Relationship between large subject matter areas

Engine-pertinent apparatus for adding non-fuel substances or small quantities of secondary fuel to combustion-air, main fuel, or fuel-air mixture, F02M 25/00;

Electrical control of supply of combustible mixture or its constituents, F02D 41/00; Methods of operating engines involving adding non-fuel substances or anti-knock agents to combustion air, fuel or fuel-air mixtures of engines, F02B 47/00.

References relevant to classification in this group
This subclass/group does not cover:
Methods and electrical aspects of controlling exhaust gas recirculation
Informative references
Attention is drawn to the following places, which may be of interest for search:
Chemical or biological purification of waste gases, e.g. engine exhaust gases, smoke, fumes, fuel gases, aerosols.
Glossary of terms
In this subclass/group, the following terms (or expressions) are used with the meaning indicated:
Non-airborne oxygenSecondary air
Oxygen not from the airAir not entering main intake
Controlling engines characterized by their being supercharged
Definition statement
This subclass/group covers:

Control systems for controlling the power output or rotational speed of the engine by other means than the throttle valve. In case of a supercharged engine it is possible for the power output or rotational speed to be additionally influenced for example by way of a controllable valve which is arranged parallel to the compressor in the induction track of the engine.

Relationship between large subject matter areas

Engines characterised by provision of pumps for charging or scavenging, F02B 33/00; engines characterised by provision of pumps driven at least for part of the time by exhaust, F02B 37/00.

References relevant to classification in this group
This subclass/group does not cover:
Electrical control of supply of combustible mixture or its constituents
Informative references
Attention is drawn to the following places, which may be of interest for search:
Component parts, details, or accessories relating to, driven charging or scavenging pumps, not provided for in groups F02B 33/00 to F02B 37/00
Glossary of terms
In this subclass/group, the following terms (or expressions) are used with the meaning indicated:
Supercharged
Turbocharged
Synonyms and Keywords

In patent documents the following expressions/words "supercharged" and "turbocharged " are often used as synonyms.

Controlling two or more co-operating engines
Definition statement
This subclass/group covers:

Methods and devices for controlling engine arrangements comprising at least a first and a second internal combustion engine, wherein each engine comprises a crankshaft and at least one cylinder with a piston connected to said crankshaft, a controllable clutch arranged between the crankshafts, an engine control unit (ECU) for controlling the first and second engine and sensors for monitoring at least one operating parameter for the said engines connected to the engine control unit.

Relationship between large subject matter areas

Propulsion units for ships, B63H 21/00; propulsion units for trains, B61C 11/00; power plants, F01K 7/00; transmitting power from propulsion power plant to

propulsive elements, B63H 23/00.

References relevant to classification in this group
This subclass/group does not cover:
Conjoint control of vehicle sub-units of different type or different function
Cutting out individual cylinders
Controlling engines, such controlling being peculiar to the devices driven thereby
Informative references
Attention is drawn to the following places, which may be of interest for search:
Combinations of two or more engines, not otherwise provided for
Glossary of terms
In this subclass/group, the following terms (or expressions) are used with the meaning indicated:
Conjoint control
Control of 2 or more cooperating engines
Master and slave engine
Primary and secondary engine
Controlling engines characterized by their being reversible
Definition statement
This subclass/group covers:

Engines that can be operated in two directions, i.e. of which the crankshaft can turn in two directions during running of the engine. These engines require amongst others displaceable camshafts. The reversing requires a control program during which several parameters of the engine, e.g. speed, throttle- position, fuel supply should be controlled.

Relationship between large subject matter areas

Ship propulsion units, B63H 21/00.

References relevant to classification in this group
This subclass/group does not cover:
Toothed gearings for reversing rotary motion
Informative references
Attention is drawn to the following places, which may be of interest for search:
Use of propulsion power plants or units on vessels
Modifications of valve-gear to facilitate reversing
Other engines
Program-control of engines (programme-control specific to a type or purpose covered by one of the groups of this subclass except groups F02D 29/00, F02D 39/00, or by one group of another subclass e.g. F01L, see that group; programme-control in general G05B 19/00 )
Definition statement
This subclass/group covers:

Program-control of engines. Although operator control is suitable for automobile engines, there are many systems, such as standby emergency electric power systems, where this type of control is impractical and expensive. For these applications, automatic program control systems have been devised which perform necessary engine control functions without operator attendance. Programme control is also used in remote starting systems for automobile engines for example heating up the passenger cabin.

Relationship between large subject matter areas

Electrical control of supply of combustible mixture or its constituents, F02D 41/00; conjoint electrical control of two or more functions, F02D 43/00; electrical control not provided for in groups F02D 41/00- F02D 43/00.

References relevant to classification in this group
This subclass/group does not cover:
Controlling engines, dependent on conditions exterior or interior to engines
Program control in general
Informative references
Attention is drawn to the following places, which may be of interest for search:
Automatic vehicle control systems
Controlling the engine output power by varying inlet or exhaust valve operating characteristics, e.g. timing
Starting of engines by means of electric motors
Traffic control systems for road vehicles
Controlling engines, such controlling being peculiar to the devices driven thereby, the devices being other than parts or accessories essential to engine operation, e.g. controlling of engines by signals external thereto
Definition statement
This subclass/group covers:

Control systems characterised by the device driven by the engine. This device can be for example a vehicle, a pump or an electric generator.

Relationship between large subject matter areas

Electrical control of internal combustion engines, F02D 39/00- F02D 45/00; positive displacement machines for liquids, F04B/00; controlling electric generators, H02P.

References relevant to classification in this group
This subclass/group does not cover:
Arrangement or mounting of plural diverse prime-movers for mutual or common propulsion, e.g. hybrid propulsion systems comprising electric motors and internal combustion engines
Conjoint control of vehicle sub-units of different type or different function
Control systems specially adapted for hybrid vehicles
Informative references
Attention is drawn to the following places, which may be of interest for search:
Propellers
Control e.g. of pump delivery, or of pump pressure, or safety measures for, machines, pumps, or pumping installations, not otherwise provided for.
Arrangements for controlling electric generators for the purpose of obtaining a desired output
Use of speed-sensing governors to control combustion engines, not otherwise provided for
Definition statement
This subclass/group covers:

Mechanical governors, e.g. Watt type

[N:Electric control of rotation speed]
Definition statement
This subclass/group covers:

Electrical control of engine rotation speed, e.g. by including a speed feedback loop

[N:controlling air supply]
Definition statement
This subclass/group covers:

Controlling the air supply, mainly by changing the throttle position, in order to control the engine speed

References relevant to classification in this group
This subclass/group does not cover:
Vehicle cruise control
[N:for idle speed control]
Definition statement
This subclass/group covers:

Throttle opening control after engine speed in idle mode; also setting of idle speed

[N:by controlling a throttle stop]
Definition statement
This subclass/group covers:

Control whereby an electric actuator urges the throttle, or the throttle lever from its closed position

[N:by controlling a throttle by-pass]
Definition statement
This subclass/group covers:

Control whereby in a bypass the air flow must be controlled after engine speed and throttle position

[N:for maximum speed control]
Definition statement
This subclass/group covers:

Control whereby throttle is used to limit engine speed.

[N:controlling fuel supply]
Definition statement
This subclass/group covers:

Rotation speed control by fuel amount, e.g. Diesel governors

[N: for idle speed control]
Definition statement
This subclass/group covers:

Feedback control of idling speed using fuel supply

Controlling delivery of fuel or combustion-air, not otherwise provided for [N: (using exhaust gas sensors F02D 35/0023, F02D 35/0046 )]
Definition statement
This subclass/group covers:

Controlling the feeding of liquid fuel from storage containers to carburettors or fuel-injection apparatus or the controlling the delivery of combustion air.

Relationship between large subject matter areas

Electrical control of supply of combustible mixtures, F02D 41/00; apparatus or systems for feeding liquid fuel from storage containers to carburettors or fuel-injection apparatus, F02M 37/00.

References relevant to classification in this group
This subclass/group does not cover:
Controlling air supply using exhaust gas sensors
Controlling fuel supply using exhaust gas sensors
Informative references
Attention is drawn to the following places, which may be of interest for search:
Control of electrical fuel pumps
Control of fuel flow to a common rail
Glossary of terms
In this subclass/group, the following terms (or expressions) are used with the meaning indicated:
Storage containers
Fuel tanks
Synonyms and Keywords

In patent documents the following expressions/words "common rail" and "fuel rail" are often used as synonyms.

Controlling engines, dependent on conditions exterior or interior to engines, not otherwise provided for
Definition statement
This subclass/group covers:

Controlling engines using information, e.g. sensor signals, about conditions exterior or interior to engines

[N: using electrical feedback (F02D 35/0015 takes precedence)]
Definition statement
This subclass/group covers:

Position feedback on an electrical actuator.

[N: using exhaust gas sensors (F02D 41/14 takes precedence)]
Relationship between large subject matter areas

This group contains engine controls using an exhaust gas sensor. Engine control using a gas sensor for sensing composition of combustion gases is classified in F02D 41/1438.

[N: Controlling air supply]
Definition statement
This subclass/group covers:

Control of air supply as a function of an air/fuel sensor signal

[N: Controlling fuel supply]
Definition statement
This subclass/group covers:

Fuel supply control after an air/fuel sensor.

[N: by means of a carburettor]
Definition statement
This subclass/group covers:

Carburettor control after an air/fuel sensor

[N: Controlling the emulsifying air only (F02D 35/0076, F02D 35/0084 take precedence)]
Definition statement
This subclass/group covers:

Controlling the emulsifying air only wherby most of the carburettors have a sub carburettor and it is the air/fuel mixture made in this sub carburettor (easier to control) which is drawn into the main venturi of the carburettor.

[N: Controlling the fuel flow only (F02D 35/0076, F02D 35/0084 take precedence)]
Definition statement
This subclass/group covers:

Fuel flow control via a valve in series in the fuel alimentation of the said sub carburettor or via a valve controlling the supply of air above the constant level fuel reservoir. If this valve is closed, less fuel can be sucked into the engine.

[N: using variable venturi carburettors]
Definition statement
This subclass/group covers:

Fuel flow using variable venturi carburettors, i.e. a special type of horizontal carburettor still used in the 80s.

on interior conditions
Definition statement
This subclass/group covers:

Control according to parameters interior to the combustion chamber that may be used to influence this combustion

References relevant to classification in this group
This subclass/group does not cover:
Knock control using ignition timing
Ignition timing control based on combustion pressure
[N: using an ionic current sensor]
References relevant to classification in this group
This subclass/group does not cover:
Ionic sensor for testing of ignition
Special rules of classification within this group

If the sensor is located in the combustion gases then classify in F02D 35/021 and F02D 41/1444 .

[N: using an optical sensor, e.g. in-cylinder light probe]
References relevant to classification in this group
This subclass/group does not cover:
Optical sensors in the exhaust system
Controlling conjointly two or more functions of engines, not otherwise provided for
one of the functions being ignition (ignition control per se F02P, [N: automatically advancing or retarding ignition combined with electronic control of other engine functions, e.g. fuel injection F02P 5/045 ])
Definition statement
This subclass/group covers:

Conjoint control using ignition timing and at least another parameter, e.g. air amount or fuel injection.

Other non-electrical control
Definition statement
This subclass/group covers:

Non-electrical control of four- or two-stroke engines; of engines adding the fuel substantially at the end or before the compression stroke; of free piston engines.

Relationship between large subject matter areas

Controlling engines, dependent on conditions exterior or interior to engines, not otherwise provided for F02D 35/00

References relevant to classification in this group
This subclass/group does not cover:
Two stroke engines
Controlling engines, such controlling being peculiar to the devices driven thereby
Rotary engines
Free piston engines
Informative references
Attention is drawn to the following places, which may be of interest for search:
Other types of engines, e.g. double acting engines
Glossary of terms
In this subclass/group, the following terms (or expressions) are used with the meaning indicated:
Free piston engines
Engines without rotary main shaft
Synonyms and Keywords

In patent documents the following expressions/words "non-electrical control" and "mechanical control" are often used as synonyms.

Electrical control of supply of combustible mixture or its constituents (F02D 43/00 takes precedence)
Definition statement
This subclass/group covers:

Electrical or electronical control of combustion engines

Relationship between large subject matter areas

Non-electrical aspects of electrically controlled devices are covered by

groups F02D 1/00 to F02D 39/00 or by subclass F02M;

- both electrical and non-electrical aspects of electrically controlled devices

are covered by groups F02D 1/00 to F02D 39/00 or by subclass F02M

References relevant to classification in this group
This subclass/group does not cover:
Control of engine starters
Electrical control of engine ignition timing
Informative references
Attention is drawn to the following places, which may be of interest for search:
Conjoint control of vehicle sub-units including control of combustion engine
Detection of engine misfires
Detection of engine knocking
Gas sensors, e.g. oxygen sensors
Special rules of classification within this group

Main group F02D 41/00 is not used. Use F02D41/00B or F02D 41/3005 instead.

Glossary of terms
In this subclass/group, the following terms (or expressions) are used with the meaning indicated:
EGR
Exhaust gas recirculation
Synonyms and Keywords

In patent documents the following abbreviations are often used:

VVT
Variable valve timing
[N: Details not otherwise provided for]
Definition statement
This subclass/group covers:

Casings or cooling of control circuits, special parameters or sensors.

[N: Controlling intake air]
Definition statement
This subclass/group covers:

Control of intake air amount, e.g. by using:

Throttle

Swirl throttle (Dralldrossel) on the side of intake pipe or in a second special intake pipe. It makes air flow to be twisted at low speeds to promote homogenization between air and fuel mist.

Variable valve timing and/or lift

Informative references
Attention is drawn to the following places, which may be of interest for search:
[N: for control of turbo-charged or super-charged engines (control of the pumps per se F02B 37/12 )]
Informative references
Attention is drawn to the following places, which may be of interest for search:
Control of turbochargers and superchargers per se
Mechanical control of turbocharged injected engine
[N: Controlling engines characterised by use of non-liquid fuels, pluralities of fuels, or non-fuel substances added to the combustible mixtures]
Definition statement
This subclass/group covers:

Controlling engines running with:

- non-liquid fuels- multiple fuels, e.g. different octane rates, alcohol + gasoline- additives added to the fuel/air (for catalyst, for enhancing burning (pure O2, N2O), etc)- alcohol, methanol and problems linked to the fuel quality/property

References relevant to classification in this group
This subclass/group does not cover:
Control using fuel type or fuel quality sensor
Control using fuel type or fuel quality estimation
Gas engines
Informative references
Attention is drawn to the following places, which may be of interest for search:
More mechanical aspects of control
Corresponding arrangements
[N: Adding fuel vapours, e.g. drawn from engine fuel reservoir
Definition statement
This subclass/group covers:

Control of the supply of fuel vapours which are normally drawn from a canister which adsorbs fuel vapours generated in the fuel tank

Informative references
Attention is drawn to the following places, which may be of interest for search:
System arrangements for fuel vapour purging
Fuel vapour system diagnosis
[N: Controlling the purging of the canister as a function of the engine operating conditions]
Definition statement
This subclass/group covers:

Engine conditions are taken into account and purging is controlled

[N: to achieve a special effect, e.g. to warm up the catalyst
Definition statement
This subclass/group covers:

Purging is used for a particular effect on the engine, e.g. to warm-up catalyst

[N: for diagnosing the engine (diagnosis of purge control systems F02M 25/0809 )]
Definition statement
This subclass/group covers:

Control of purging to achieve conditions which are suitable for engine Diagnosis. - If the expected effect due to purging does not occur, failure is determined- Switch off of purging to prevent influence on diagnosis

References relevant to classification in this group
This subclass/group does not cover:
Diagnosis of purge control systems
[N: Control of the valve or purge actuator, e.g. duty cycle, closed loop control of position]
Definition statement
This subclass/group covers:

Details specific to the control of the purge valve itself

[N: Controlling the combustible mixture as a function of the canister purging, e.g. control of injected fuel to compensate for deviation of air fuel ratio when purging]
Definition statement
This subclass/group covers:

Control of the engine mixture is adapted to purging taking place

[N: Estimating, calculating or determining the purging rate, amount, flow or concentration]
Definition statement
This subclass/group covers:

Details specific to the estimation, calculation or any kind of determination of the purge quantity

Controlling exhaust gas recirculation [EGR] (temperature control with cooler in recirculation circuit F02M 25/0738 )
Definition statement
This subclass/group covers:

Electrical control of exhaust gas recirculation (EGR)

Informative references
Attention is drawn to the following places, which may be of interest for search:
Mechanical control of EGR
Temperature control using EGR cooler
Constructional aspects of EGR circuits
Diagnosis of EGR
[N: Feedback control of engine parameters, e.g. for control of air/fuel ratio or intake air amount]
Definition statement
This subclass/group covers:

Feedback control using EGR for all parameter not directly related to EGR. This might include:

intake amount amount

intake manifold pressure

air/fuel ratio

combustion timing

engine roughness

References relevant to classification in this group
This subclass/group does not cover:
Internal EGR rate or amount feedback
External EGR rate or amount feedback
Special rules of classification within this group

The feedback parameter should be classified in the corresponding groups as well

[N: Special engine operating conditions, e.g. for regeneration of exhaust gas treatment apparatus]
Definition statement
This subclass/group covers:

Special control of EGR for non-ordinary operating conditions, e.g.:

- engine diagnosis- during fuel cut- Exhaust catalyst regeneration

[N: Specific combustion modes (combustion modes per se F02D 41/3017 )]
Definition statement
This subclass/group covers:

EGR control according to or during engine operation with specific combustion modes, e.g. special engines with two EGR modes on both sides of the peak of smoke which appears when the EGR rate is increased in a diesel engine or HCCI without anything specific to EGR control

Relationship between large subject matter areas

Feedback control of EGR to control combustion timing e.g. in HCCI mode; F02D 41/0052

Informative references
Attention is drawn to the following places, which may be of interest for search:
Combustion modes
[N: using internal EGR (control of valve overlap for internal EGR F02D 13/0261; arrangements for internal EGR F02M 25/0752 )
Definition statement
This subclass/group covers:

Exhaust gases are redirected into the combustion chamber or kept as residual gases during positive or negative valve overlap

Informative references
Attention is drawn to the following places, which may be of interest for search:
Valve overlap control
Arrangements for internal EGR
[N: Estimating, calculating or determining the internal EGR rate, amount or flow]
Definition statement
This subclass/group covers:

Determination of the EGR rate or residual gas amount remaining in the cylinder when internal EGR is used

Special rules of classification within this group

Only as additional information if parameter is only mentioned without details on how to determine it

[N: Specific aspects of external EGR control (constructional details of EGR system F02M 25/07 )]
Definition statement
This subclass/group covers:

something specific to external EGR, e.g. considering transport delays or when using low pressure and high pressure EGR circuits

[N: Estimating, calculating or determining the EGR rate, amount or flow (sensors in EGR systems F02M 25/0753 )]
Definition statement
This subclass/group covers:

Determination of the EGR rate in external EGR circuits

Special rules of classification within this group

Only as additional information if parameter is only mentioned without details on how to determine it

[N: Control of the EGR valve or actuator, e.g. duty cycle, closed loop control of position (EGR valve position sensor F02M 25/0756 )]
Informative references
Attention is drawn to the following places, which may be of interest for search:
EGR valve position sensors
[N: Controlling each cylinder individually]
Definition statement
This subclass/group covers:

Operation of individual engine cylinders with different operating parameters, e.g. different fuel amounts or air amounts

Informative references
Attention is drawn to the following places, which may be of interest for search:
Cylinder individual control of ignition timing
Special rules of classification within this group

Multiple classification for the corresponding actuator(s) applies

[N: per groups or banks (F02D 41/0087 takes precedence)]
Definition statement
This subclass/group covers:

Operation of cylinder groups with different operating parameters, e.g. first cylinder group operating lean and second cylinder group operating rich to achieve heating or regeneration of catalysts

Special rules of classification within this group

This group is not used for deactivation of cylinder banks which should be classified in F02D 41/0087 only

[N: Balancing of cylinder outputs, e.g. speed, torque or air-fuel ratio]
Definition statement
This subclass/group covers:

Control to equalise engine operating parameter for all cylinders

Relationship between large subject matter areas

There might be some overlap with F02D 41/1498, however F02D 41/1498 covers at least measuring/detecting roughness per se, control according to roughness when all cylinders are controlled in the same way (e.g. idling/lean rough limit). If there is roughness detection and individual control then both groups should be used. Some overlap with engine roughness

[N: Selective cylinder activation, i.e. partial cylinder operation (deceleration cut-off F02D 41/123 )]
Definition statement
This subclass/group covers:

Selective activation or deactivation of cylinders: every cylinder is fed with an optimal fuel quantity for an optimal combustion or with no fuel at all. The engine power also being controlled by the number of fed cylinders and not by the throttle and the air/fuel per cylinder.

References relevant to classification in this group
This subclass/group does not cover:
Complete fuel-cut in all cylinders during deceleration
using means for generating position or synchronisation signals
Definition statement
This subclass/group covers:

Detection of engine crank angle position and generation of synchronisation signals, i.e. information about which cylinder is in which cycle (intake, compression, expansion or exhaust cycle).

Informative references
Attention is drawn to the following places, which may be of interest for search:
Position for ignition
using means for generating speed signals
Definition statement
This subclass/group covers:

Detection and measurement of engine speed.

Informative references
Attention is drawn to the following places, which may be of interest for search:
Rotation speed measurement in general
Circuit arrangements for generating control signals
Special rules of classification within this group

This group should not be used.

[N: using an auxiliary engine speed control (engine speed control per se F02D 31/00 )]
Definition statement
This subclass/group covers:

Generator, pump or PTO (e.g. agricultural Power Take Off) engines with an externally needed regulated speed control.

References relevant to classification in this group
This subclass/group does not cover:
Vehicle cruise speed control
[N: Introducing corrections for particular conditions exterior to the engine (conjoint control of vehicle sub-units for propelling the vehicle B60W 30/18 )]
Definition statement
This subclass/group covers:

Control according to particular conditions exterior to the engine, e.g.

- positional information from navigation systems

- road conditions

- engine control in relation with other vehicle sub-systems

Special rules of classification within this group

The conditions exterior to the engine should also be classified in F02D 2200/70.

[N: in relation with elements of the transmission]
Definition statement
This subclass/group covers:

Control of the engine in relation with gearbox and/or clutch

Informative references
Attention is drawn to the following places, which may be of interest for search:
More general aspects of driveline control, conjoint control of driveline elements
[N: in relation with the gear ratio shifting (conjoint control for improving gear change B60W30/18M )]
Definition statement
This subclass/group covers:

Special control during the gear shift. Usually torque or speed control to target values

Informative references
Attention is drawn to the following places, which may be of interest for search:
Conjoint control to improve gear change
B60W30/18M
[N: in relation with the state of the exhaust gas treating apparatus (control of exhaust gas treating apparatus per se F01N)]
Definition statement
This subclass/group covers:

Control of engine in order to achieve specific effect on exhaust gas treatment device, e.g. regeneration or warming-up

Relationship between large subject matter areas

Borderline between F02D 41/0235 and F01N is defined based on where the intervention to achieve heating or regeneration takes place:

- F02D 41/0235 if the engine control is affected

- F01N if the control takes place in the exhaust, e.g. by injection into the exhaust pipe or electrical heating for catalysts

[N: to increase temperature of the exhaust gas treating apparatus]
Definition statement
This subclass/group covers:

Engine control to increase the temperature of an exhaust gas catalyst or filteralso given for regeneration, when method for temperature increase is important

[N: by increasing temperature of the exhaust gas leaving the engine]
Definition statement
This subclass/group covers:

Methods for raising catalyst temperature wherein additional heat is generated by combustion inside cylinder, e.g. by early post injection and delaying (main) injection timing.

[N: by changing the composition of the exhaust gas, e.g. for exothermic reaction on exhaust gas treating apparatus]
Definition statement
This subclass/group covers:

Methods for raising catalyst temperature wherein additional heat is generated in exhaust pipe or on catalyst, e.g. by late post injection with surplus of oxygen from same/other cylinder, or by driving cylinders with different air/fuel ratios so that exhaust gases from these cylinders mix in exhaust pipe.

[N: to purge or regenerate the exhaust gas treating apparatus]
Definition statement
This subclass/group covers:

Engine control without special control according to the type of catalyst

[N: the exhaust gas treating apparatus being a NOx trap or adsorbent]
Special rules of classification within this group

Parameters characterising the state of the exhaust gas treating apparatus should be classified in F02D 2200/08 as well. F02D 2200/0806-F02D 2200/0811 are of particular importance for NOx traps.

[N: Desulfurisation of NOx traps or adsorbent]
Special rules of classification within this group

Parameters characterising the state of the exhaust gas treating apparatus should be classified in F02D 2200/08 as well. F02D 2200/0818 is of particular importance for the desulfurisation of NOx traps.

[N: the exhaust gas treating apparatus being a particulate filter]
Informative references
Attention is drawn to the following places, which may be of interest for search:
Regenerating particle filter with means in exhaust;
Special rules of classification within this group

Parameters characterising the state of the exhaust gas treating apparatus should be classified in F02D 2200/08 as well. F02D 2200/0812 is of particular importance for the regeneration of particle filters.

[N: Control according to the amount of oxygen that is stored on the exhaust gas treating apparatus]
Definition statement
This subclass/group covers:

Control of engine air/fuel ratio so that amount of oxygen that is stored on (three-way)-catalyst with oxygen storage capacity meets target value.

Special rules of classification within this group

Parameters characterising the state of the exhaust gas treating apparatus should be classified in F02D 2200/08 as well. F02D 2200/0814 and F02D 2200/0816 are of particular importance for this group.

[N: for stopping the engine]
Definition statement
This subclass/group covers:

Control for stopping the engine or during the engine stopping period

Informative references
Attention is drawn to the following places, which may be of interest for search:
Stopping of diesel engines
[N: Taking into account fuel evaporation or wall wetting; (special correction after fuel cut-off F02D 41/126 )]
Definition statement
This subclass/group covers:

Control combining partial pressures of vapour fuel, fresh air, recycled exhaust gas, less deposited fuel to calculate real air/fuel ratio taken in each cylinder

Control using models to determine fuel film on intake and cylinder walls

for engine starting or warming up [N: (F02D 41/0255 takes precedence)]
Definition statement
This subclass/group covers:

Corrections during engine start or warm-up.

[N: the corrections being time dependent]
Definition statement
This subclass/group covers:

Corrections during engine start linked to a delay or timer.

[N: for starting (F02D 41/061 takes precedence)]
Definition statement
This subclass/group covers:

Corrections during engine start.

[N: at cold start (F02D 41/067 takes precedence)]
Definition statement
This subclass/group covers:

Engine control during engine start when engine is cold, e.g. increase of fuel injection amount to compensate increased fuel demand.

[N: at hot start or restart (F02D 41/067 takes precedence)]
Definition statement
This subclass/group covers:

Engine start when engine is warm or immediate restart, e.g. after stall or during engine start/stop control

[N: with control of the choke (non electronic control of choke see F02M 1/10 )]
Definition statement
This subclass/group covers:

Purely electrical chokes as well as mechanical automatic chokes where the bimetallic spiral or wax actuator is electrically heated when the engine has started.

[N: for warming-up]
Definition statement
This subclass/group covers:

Warming-up measures, e.g. fast idle to accelerate warming-up

for idling (F02D 41/06, F02D 41/16 take precedence)
Definition statement
This subclass/group covers:

Engine control during idling

Informative references
Attention is drawn to the following places, which may be of interest for search:
Feedback control of idling speed
F02D31/00D2B, F02D31/00D4B
[N: taking into account engine load variation, e.g. air-conditionning]
Definition statement
This subclass/group covers:

Engine control during idling considering external loads, e.g.

- air condition

- generators

- power steering

for acceleration
Definition statement
This subclass/group covers:

Engine control during acceleration, e.g. increase of fuel injection amount to meet increased demand.

[N: Switching from sequential injection to simultaneous injection]
Definition statement
This subclass/group covers:

Increase of the number of injectors in intake low pressure injection to increase fuel flow

[N: using asynchronous injection]
Definition statement
This subclass/group covers:

Control with extra fuel pulse at start of acceleration in addition to ordinary fuel pulses which are sequentially injected at regular intervals

[N: the fuel injection being cut-off]
Definition statement
This subclass/group covers:

The fuel being cut off in all cylinders during deceleration as long as there is no serious reason to restart.

Informative references
Attention is drawn to the following places, which may be of interest for search:
Selective activation/deactivation of some, but not all cylinders
[N: transitionnal corrections at the end of the cut-off period]
Definition statement
This subclass/group covers:

When the engine is decelerating it is necessary to restart the engine before idle speed is reached to avoid stalling if injection is restarted too late. Transitional measures may also be taken before. Special control to bring back catalyst to normal working range

[N: Characterised by the control or regulation method (F02D 41/1473, F02D 41/1477 take precedence)]
Definition statement
This subclass/group covers:

Documents giving details on the feedback loop should be put in this group and groups when it is not a PID or some basic controller, then prefer to classify in F02D 41/1473 and F02D 41/1477

Informative references
Attention is drawn to the following places, which may be of interest for search:
Control in general
Special rules of classification within this group

Classifiy as well according to what is controlled or what is measured., e.g. F02D 41/1438, F02D 41/16

[N: Adaptive control]
Definition statement
This subclass/group covers:

The parameters/coefficients of the controller are set/tuned on-line according to the output of the system (there must be a feedback). Also called Self-Tuning regulator.

Relationship between large subject matter areas

Not to be confused with "learning" where some values are stored to be re-used. This should be classified in F02D 41/2429. A controller having different coefficients stored in a table and where the coefficients are chosen according to operating conditions should be classified in F02D 2041/1422.

[N: Dithering techniques]
Informative references
Attention is drawn to the following places, which may be of interest for search:
Dithering for learning in air/fuel ratio control
[N: using means for determining characteristics of the combustion gases; Sensors therefor]
Definition statement
This subclass/group covers:

Control according to a characteristic of the combustion gases.

[N: Sensor in intake manifold]
Definition statement
This subclass/group covers:

Use of a gas concentration sensor in the intake manifold, e.g. to measure the O2/fuel ratio before the mixture enters the combustion chambers on order to avoid the two-revolutions delay.

[N: Plural sensors]
Definition statement
This subclass/group covers:

Multiple sensor arrangements in the exhaust system, e.g. one sensor before the catalyst converter and one after to check its functioning

Downstream sensor might be used for tuning the air/fuel ratio loop based on the upstream sensor

[N: with one sensor per cylinder or group of cylinders]
Definition statement
This subclass/group covers:

A sensor is provided for each cylinder group or bank, e.g.in the case of V- or flat engines for example

[N: characterised by the characteristics of the combustion gases or the type of sensor used]
Informative references
Attention is drawn to the following places, which may be of interest for search:
Gas sensors in general
[N: the sensor being an optical sensor]
Definition statement
This subclass/group covers:

Use of an optical sensor in the exhaust system, e.g. for smoke measurements by evaluating the color/transparency of the exhaust gases.

References relevant to classification in this group
This subclass/group does not cover:
Optical sensors in combustion chamber
[N: Regulating the air fuel ratio at a value other than stoechiometry]
Definition statement
This subclass/group covers:

Engine control to achieve an air-fuel ratio deviating from the stoichiometric air/fuel ratio, e.g. by:

- shifting the comparator level- having different rising and descending slopes for the integral or the proportional part of the control- using a linear sensor

[N: Biasing of the sensor]
Definition statement
This subclass/group covers:

Two-states sensors wherein a flow of O2 ions across the porous sensor is simulated by simply sending electrons

[N: characterised by the regulation circuit or part of it, (e.g. comparator, PI regulator, output)]
Definition statement
This subclass/group covers:

Air/fuel ratio control circuits and its components

[N: Using a comparator with variable reference]
Definition statement
This subclass/group covers:

Air/fuel ratio control with two-state air/fuel ratio sensor wherein the air/fuel ratio sensor signal is compared with a variable reference to have a lambda regulation value different from 1

Adaptation of the comparator value to variation of sensor characteristics, e.g. with temperature or age

[N: Using a plurality of comparators]
Definition statement
This subclass/group covers:

Air/fuel ratio control using a plurality of comparators, e.g. by selecting among them according to circumstances, to have a lambda regulation value different from 1.

[N: Using a delaying circuit]
Definition statement
This subclass/group covers:

Control related to the problem caused by the delay between the fuel injection and the sensing of exhaust gas properties due to travel in intake, compression, expansion, exhaust and travel in exhaust. To reduce the generated oscillation in steady some delays are introduced in the regulation loop.

[N: with correction for particular operating conditions]
Definition statement
This subclass/group covers:

Air/fuel ratio control during particular operating conditions, e.g. during transient conditions.

[N: Inhibiting the regulation]
Definition statement
This subclass/group covers:

Deactivation of air/fuel control based on exhaust sensor measurements, e.g. during transitions

[N: Details]
Definition statement
This subclass/group covers:

Constructional details of the air/fuel control circuit or its componentsAir/fuel ratio sensor input circuits

[N: Control of sensor heater]
Definition statement
This subclass/group covers:

Control of heating of an exhaust gas sensor to its operating temperature

[N: Detection of abnormalities in the air/fuel ratio feedback system]
Definition statement
This subclass/group covers:

Detection of abnormalities in the air/fuel ratio feedback system, especially air/fuel ratio sensor failure detection, e.g. by checking its temperature, its resistivity, its speed of reaction or its output voltage range.

Informative references
Attention is drawn to the following places, which may be of interest for search:
Sensor diagnosis per se
[N: With detection of the mechanical response of the engine
Definition statement
This subclass/group covers:

Control using demanded and measured torque, power etc...

[N: measuring engine roughness
Definition statement
This subclass/group covers:

Detection of roughness caused by misfires due to insufficient fuel in the cylinder or due to a too late ignition not able to reach the fuel cloud. Misfire is a lack of combustion. Detection of roughness caused by different contributions of individual cylinders

[N: by measuring intake air flow (measuring flow in general G01F)]
Definition statement
This subclass/group covers:

Direct air mass measurement

Three types of sensors:

- air flaps normally classified here, with a plate pushed away by air dynamic pressure, which moves a potentiometer giving a resistance or a voltage proportionnal to air flow,

- vortex (Karmann) flowmeters which give a frequency directly proportionnal to the mass of air flowing in the pipe see F02D 41/185

hot wires using a wire which resistance varies with temperature, and which is heaten by electric current and cooled by the air passing on it: they also give a voltage see F02D 41/187

Computed air flow after manifold depression or throttle opening may also be here with the keyword "parameter measurement - air model"

Relationship between large subject matter areas

There are two schools of injection control: the density based injection where an intake vacuum was combined with rpm after eventual temperature correction and a air-mass based based on an direct air mass flow measure.

Informative references
Attention is drawn to the following places, which may be of interest for search:
Measuring the volume flow or mass flow in general
Output circuits, e.g. for controlling currents in command coils(current control in inductive loads in general H03K 17/64 )
Definition statement
This subclass/group covers:

Circuits for driving injection valves but also gas exchange valves in engines

[N: for controlling piezo-electric injectors (drive and control circuit for piezo-electric devices in general H01L 41/042 )]
Informative references
Attention is drawn to the following places, which may be of interest for search:
Drive and control circuit for piezo-electric devices in general
Safety or indicating devices for abnormal conditions s [N: (in air/fuel ratio feedback systems F02D 41/1495, in electric control linkage F02D 11/107, in purge control systems F02M 25/0809 )]
Definition statement
This subclass/group covers:

Devices and methods for diagnosing the engine or specific components, e.g. actuators or sensors

Relationship between large subject matter areas

For the diagnosis, the type of the diagnosed actuator or the diagnosed sensor should be classified as well in the corresponding group, e.g.

F02D 41/30 for fuel injectors and F02D 41/1444 for exhaust sensors others than air/fuel ratio sensors

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

This group does not cover diagnosis of:

Air/fuel ratio feedback systems including air/fuel ratio sensor diagnosis
Electric control linkage, e.g. throttles
EGR systems
Fuel vapour purge systems
Exhaust gas treatment systems, e.g. catalytic converters
Informative references
Attention is drawn to the following places, which may be of interest for search:
Testing of engine ignition
Testing electrical properties on transport means
Registering data indicating performance e.g. black boxes
Detection of engine misfires
Detection of engine knocking
Testing of engines on test benches
[N: Addressing techniques specially adapted therefor]
Definition statement
This subclass/group covers:

Choice of addressing parameters for parameter retrieval using maps, e.g. rpm, throttle opening and intake pressure, for example

[N: One-parameter addressing technique]
Definition statement
This subclass/group covers:

Maps with only one input parameter

[N: Interpolation techniques]
Definition statement
This subclass/group covers:

Use of interpolation for operating points which are grid points of the maps

[N: Non-linear variation along at least one coordinate]
Definition statement
This subclass/group covers:

Choice of a logarithmic or an inverted value for a parameter to save memory space

[N: Selective use of one or more tables]
Definition statement
This subclass/group covers:

Choice of different tables according to certain criteria, e.g. fuel type, to combustion modes

[N: Methods of calibrating or learning]
Definition statement
This subclass/group covers:

Learning of engine, sensor or actuator characteristics, e.g. by learning an additive or multiplicative correction value to displace a complete table or a plurality of points of a complete table depending on the results of the learning.

Learning to consider dispersions between actuators or sensors.

Learning of control values to considers changes of engine, sensor or actuator characteristics due to aging

[N: Methods for rewriting]
Definition statement
This subclass/group covers:

Rewriting part of the controller memory with new data, e.g. during engine inspections, and associated methods

[N: Methods for preventing the loss of data]
Definition statement
This subclass/group covers:

Use of (semi-)permanent memories or using permanent batteries to feed normal memories

[N: the computer being backed-up or assisted by another circuit, e.g. analogue]
Definition statement
This subclass/group covers:

Analog or digital circuits in addition to the main control unit, e.g.

- a second control unit, e.g. cylinder control units controlling the actuators associated to one cylinder. - watchdog circuits for monitoring the main CPU

[N: Interface circuits]
Definition statement
This subclass/group covers:

Interface circuit between the control unit and associated elements, e.g. multiplexers or signal processing units between sensors and control unit.

[N: one mode being the stratified charge spark-ignited mode]
Definition statement
This subclass/group covers:

Gasoline engines with a stratified charge, which is usually caused by injection late in the compression stroke and subsequent ignition.

Special rules of classification within this group

Semi-stratified mode with injections in intake and compression stroke should additionally receive F02D 41/402

[N: further comprising a homogeneous charge spark-ignited mode]
Definition statement
This subclass/group covers:

Engines with stratified and homogeneous modes

[N: one mode being the premixed charge compression-ignition mode]
Definition statement
This subclass/group covers:

Engine control for engines wherein the mixture is partly or homogeneously premixed and then ignited by compression.

Also called HCCI for homogeneous charge compression ignition.

[N: with means for triggering compression ignition, e.g. spark plug]
Definition statement
This subclass/group covers:

Means used to trigger the compression-ignition in premixed charge compression ignition engines, e.g.:

- injection of fluids or gases, e.g. water to delay ignition or pressurized air to create pressure wave- activation of a spark-plug to change the mixture composition- change of compression ratio shortly before TDC- laser ignition aid

[N: said means being a secondary injection of fuel]
Definition statement
This subclass/group covers:

A second, small injection shortly before the compression stroke TDC to get local air-fuel ratio above self-ignition limit. Said fuel might also be ignited by spark to cause pressure increase and subsequent self-ignition of the homogeneous mixture

Special rules of classification within this group

Multiple Injections per se, e.g. with a first injection during the negative valve overlap normally called activation injection, should be classified in F02D 41/402

[N: the engine working with a variable number of cycles ]
Definition statement
This subclass/group covers:

Engines controlled to change from 2-cycle to 4-cycle or 6-cycle mode, e.g. by changing valve actuation and injection frequency

Informative references
Attention is drawn to the following places, which may be of interest for search:
Engine conversions to change number of cycles
[N: with special control during transition between modes]
Definition statement
This subclass/group covers:

Special measures to avoid problems during combustion mode transitions, e.g. considering the delay between different actuators

[N: with special conditions for selecting a mode of combustion, e.g. for starting, for diagnosing ]
Definition statement
This subclass/group covers:

Conditions other than load/speed map for selecting one of a plurality of combustion modesAdaptation of load/speed maps for selecting combustion modes

[N: Control of electrical fuel pumps]
Special rules of classification within this group

Control of electrical low pressure pumps in common rail systems only ass additional information

of the low pressure type [N: (F02D 41/3082 takes precedence)]
Definition statement
This subclass/group covers:

Control of fuel injection into intake manifold which is not air-mass based fuel injection control, i.e. essentially air density control after intake pressure and rpm is classified here

with means for controlling injection timing or duration (ignition timing F02P 5/00 )
Informative references
Attention is drawn to the following places, which may be of interest for search:
Control of injection duration after air flow
Control of duration after manifold pressure
Injection timing
of the high pressure type]
Definition statement
This subclass/group covers:

High pressure fuel injection control, e.g. control of fuel amount of electronically controlled direct injectors.

Informative references
Attention is drawn to the following places, which may be of interest for search:
Electronic control of mechanical fuel pumps
[N: Controlling the fuel pressure]
Definition statement
This subclass/group covers:

Controlling the fuel pressure in the common rail, also setting of target values

[N: by controlling the flow into the common rail, e.g. the amount of fuel pumped]
Definition statement
This subclass/group covers:

This includes both diverting the fuel directly from the high pressure pump and the control of fuel amount directed to the pump inlet via the so-called suction control valves

[N: with elements in the low pressure part, e.g. low pressure pump ]
Definition statement
This subclass/group covers:

The amount of fuel supplied to the high pressure pump is (indirectly) controlled using the low pressure fuel pump, fuel pressure regulators in the low pressure part of the common rail system or other elements in the low pressure circuit

References relevant to classification in this group
This subclass/group does not cover:
Suction control valve in the pump inlet
[N: by controlling the flow out of the common rail, e.g. using pressure relief valves
Definition statement
This subclass/group covers:

Common rail pressure control via pressure relief valves.

[N: characterised by leakage flow in injectors]
Definition statement
This subclass/group covers:

Short actuations of the injector which cause some fuel to leak out of the injector and return to the fuel tank. These actuations are usually too short to cause fuel injector opening and therefore supply of fuel to engine.

[N: of the in-line type]
Definition statement
This subclass/group covers:

Fuel amount control in in-line injection pumps

[N: of the distributing type]
Definition statement
This subclass/group covers:

Fuel amount control in distributor injector pumps

Conjoint electrical control of two or more functions, e.g. ignition, fuel-air mixture, recirculation, supercharging, exhaust-gas treatment (electrical control of exhaust gas treating apparatus per se F01N 9/00 )
References relevant to classification in this group
This subclass/group does not cover:
Conjoint control of several parameters
Special rules of classification within this group

Used only for documents controlling the air amount after fuel amount. control of several parameters shouls be classified in right individual groups under F02D 41/00.

Electrical control not provided for in groups F02D 41/00 to F02D 43/00 (electrical control of exhaust gas treating apparatus F01N 9/00; electrical control of one of the functions; ignition, lubricating, cooling, starting, intake-heating, see relevant subclasses for such functions)
Special rules of classification within this group

This group is not used

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Last Modified: 10/11/2013