Apparatus for supplying fuel, air or non fuel substances to combustion engines, e.g. carburettors for liquid fuel; apparatus for feeding, or treating combustion-air, fuel, or fuel-air mixture; Fuel injection apparatus

When the engine is cold, fuel vaporizes less readily and tends to condense on the walls of the intake manifold, starving the cylinders of fuel and making the engine difficult to start; thus, a richer mixture is required to start and run the engine until it warms up. To provide the extra fuel, a choke is typically used; this is a device that restricts the flow of air at the entrance to the carburettor, before the venturi. With this restriction in place, extra vacuum is developed in the carburettor venturi, which pulls extra fuel through the main metering system to supplement the fuel being pulled from the idle and off-idle circuits. This provides the rich mixture required to sustain operation at low engine temperatures. In addition, the choke can be connected to a cam or other device which prevents the throttle plate from closing fully while the choke is in operation. This causes the engine to idle at a higher speed. Fast idle serves as a way to help the engine warm up quickly, and give a more stable idle while cold by increasing airflow throughout the intake system which helps to better atomize the cold fuel. In many carburetted cars, the choke is controlled by a cable connected to a pull-knob on the dashboard operated by the driver. In some carburetted cars it is automatically controlled by a thermostat employing a bimetallic spring, which is exposed to engine heat, or to an electric heating element. This heat may be transferred to the choke thermostat via simple convection, via engine coolant, or via air heated by the exhaust. Some carburettors do not have a choke but instead use a mixture enrichment circuit. Typically used on small engines, enricheners work by opening a secondary fuel circuit below the throttle valves. This circuit works exactly like the idle circuit, and when engaged it simply supplies extra fuel when the throttle is closed.

Carburettors are used in all types of engines. Nowadays new inventions mainly take place in the field of small engines. e.g. motorcycles, lawn mowers.

Devices for delivering the correct amount of fuel and air under idling i.e. slow running conditions of the engine.

Low-pressure fuel-injection apparatus, F02M 69/00.

To ensure a ready mixture, the carburettor has a float chamber that contains a quantity of fuel at near-atmospheric pressure, ready for use. This reservoir is constantly replenished with fuel supplied by a fuel pump. The correct fuel level in the bowl is maintained by means of a float controlling an inlet valve When fuel is used up, the float drops, opening the inlet valve and admitting fuel. As the fuel level rises, the float rises and closes the inlet valve. The level of fuel maintained in the float bowl can usually be adjusted by a setscrew.

Carburettors with means for influencing, e.g. enriching or keeping constant, fuel/air ratio of charge under varying conditions, F02M 7/00.

Under all engine operating conditions, the carburettor must measure the airflow of the engine, deliver the correct amount of fuel to keep the air/fuel mixture in the proper range and distribute the two finely and evenly. This job would be simple if air and gasoline were ideal fluids; in practice, however, their deviations from ideal behaviour due to viscosity, fluid drag, inertia, etc. require a great deal of complexity to compensate for exceptionally high or low engine speeds. A carburettor must provide the proper air/fuel mixture across a wide range of ambient temperatures, atmospheric pressures, engine speeds and loads and centrifugal forces, like cold start, hot start, idling, acceleration, high speed at full throttle (high load), slow speed at part throttle (light load).

To function correctly under all these conditions, carburettors contain a complex set of mechanisms to support several different operating modes.

Electrical control of supply of combustible mixture or its constituents, F02D 41/00.

A carburettor basically consists of an open pipe through which the air passes into the inlet manifold of the engine. The pipe is in the form of a venture, which narrows in section and then widens again, causing the airflow to increase in speed in the narrowest part. Below the venturi is a valve called the throttle valve. This valve controls the flow of air through the carburettor throat and thus the quantity of air/fuel mixture the system will deliver, thereby regulating engine power and speed. The throttle valve is connected through a mechanical linkage of rods and joints to the accelerator pedal.

Controlling engines by throttling air or fuel-and-air induction conduits or exhaust conduits, F02D 9/00.

Carburettors with a plurality of means for adjusting the air to fuel mixing ratio according to the operational requirements, like acceleration, deceleration and idling of the engine.

Electrical control of supply of combustible mixture or its constituents, F02D 41/00.

The arrangement of two or more carburettors on the intake conduits of internal combustion engines and related constructional features.

Combustion air cleaners, air intakes, intake silencers or induction systems specially adapted for, or arranged on, internal combustion engines, F02M 35/00.

Carburettors with means for preventing freezing or overheating of the carburettor.

Apparatus for thermally treating combustion-air, fuel, or fuel-air mixture, F02M 31/00.

Carburettors with a different type of configuration, like fuel bath carburettors or normal carburettors having special properties, like membrane carburettors.

Low-pressure fuel-injection apparatus, F02M 69/00.

Residual group for details of carburettors which are not covered by main groups F02M 1/00 – F02M 17/00. This group covers, e.g. metering orifices, spray nozzles, venturis, external control gear.

Low-pressure fuel-injection apparatus, F02M 69/00.

Systems like tanks, vaporizers, pumps and injectors for supplying engines with a non-liquid, mostly gaseous fuel. A gas engine differs from a petrol engine in many ways. The fuel and air are mixed differently. The combustion of a gas/ air mixture is different form a liquid fuel/ air mixture and requires adaptation of the combustion space. Also the energy contents of gas is much lower than that of a liquid fuel. Since (natural) gas is a clean, economical and readily available fuel, many industrial engines are either designed or modified to use gas, as distinguished from gasoline.

Controlling engines characterised by their use of non-liquid fuels, pluralities of fuels, or non-fuel substances added to the combustible mixtures, F02D 19/00.

Apparatus for adding secondary air to the air/fuel mixture for varying or keeping constant the air/fuel ratio under varying engine operating circumstances, like acceleration, deceleration, cold start and high torque.

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.

Apparatus for adding water, lubricant vapours or fuel vapours to the combustion mixture. These substances are added to improve the combustion properties of the fuel/air mixture and/or make the exhaust gases cleaner or prevent harmful gases from escaping to atmosphere.

Controlling engines characterised by their being supplied with non-airborne oxygen or other non-fuel gas, F02D 21/00

Positive crankcase ventilation [PCV] should also be classified in F01M 13/02.

Apparatus for adding exhaust gases to the combustion mixture. The exhaust gas is added to improve the combustion properties of the fuel/air mixture and/or make the exhaust gases cleaner or prevent harmful gases from escaping to atmosphere.

Apparatus for treating combustion-air, fuel or fuel-air mixture by catalysts, electric means, magnetism, (radioactive) rays or sound waves in order to improve the combustibility of the fuel-air-mixture.

Chemical, physical or physic-chemical processes in general; their relevant apparatus, B01J 19/00.

Especially when the air is cold the process of vaporisation of fuel into the air is more difficult. Apparatus for re-atomising condensed fuel, e.g. fuel droplets on the inner side of the air intake tube, or homogenising fuel-air mixture, e.g. distribution of fuel and air, help to improve this process.

Modifying induction systems for imparting a rotation to the charge in the cylinder, F02B 31/00.

Apparatus for thermally treating combustion-air, fuel or fuel-air mixture for improving the combustion properties of the fuel-air mixture.

Carburettors with heating, F02M 15/00; fuel injection apparatus with heating, F02M 53/00; fuel filters with heating, F02M 35/024; air filters with heating, F02M 35/024.

Other apparatus for treating combustion-air, fuel or fuel-air mixture, like collectors for condensed fuel, coatings of intake passages.

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

F02M 35/00 has relationships with many subject matter areas in the field F02B, F02D and F02M dealing with the air and fuel supply to the internal combustion engine.

Positive crankcase ventilation [PCV] should also be classified in F01M 13/02.

Apparatus or systems for feeding liquid fuel from storage containers to carburettors or fuel-injection apparatus, like pumps, fuel conduits and venting means, including fuel return lines.

Feeding liquid fuel from storage containers to carburettors or fuel-injection apparatus by means of driven pumps.

Arrangements for purifying liquid fuel specially adapted for, or arranged on, internal-combustion engines, e.g. arrangements in the feeding system that are characterised by filters or filter arrangements.

Arrangements for purifying liquid fuel specially adapted for, or arranged on, internal-combustion engines characterised by air purging means.

The physical or geometrical relation of fuel-injection apparatus to an engine or the drive arrangement of a fuel pump.

Arrangements of fuel-injection pumps including mounting, i.e. fitting or attaching the pumps to the engines.

Fuel injection apparatus having a driven sequential distributor, combined with or separated from a pump or common pressure source.

Injection pumps for metering and distributing fuel.

Fuel injection apparatuses operating simultaneously on two or more fuels or on a liquid fuel and another liquid, the other liquid can e.g. be an antiknock additive, e.g. water.

One of the fuels may be gaseous.

This group does not contain documents describing gaseous fuel injection system. It is limited to constructional aspects of pumps or injectors.

However fuel injection apparatuses operating simultaneously on two or more fuels, one of them being gaseous, also fall under F02M 43/00.

Both functional and constructional aspects of injection apparatus. When a pump or injector is specially designed for such injection, then they are classified in these groups.

Apparatus with each cyclic delivery being separated into two or more parts or if there is "a continuous cyclic delivery with variable pressure", or

in case "each cyclic delivery" is not "separated into two or more parts", i.e. in case injector doesn't close between parts.

Functional and constructional aspects of injection apparatus.

Apparatus having more than one injection-valve controlling discharge orifices, even if "each cyclic delivery" is not "separated into two or more parts". Also used if there is "a continuous cyclic delivery with variable pressure".

Apparatus providing a continuous cyclic delivery with variable pressure. "Variable pressure" is understood to include "variable flow rate".

Injectors only. The needle valves of these injectors are closed by a fluid pressure, with the exception of injectors classified in F02M 47/046

Illustrative example of subject matter classified in this group.

Using fluid, other than the fuel taking part of the injection, for injection-valve actuation. Thus it also covers the case where the actuation fluid is actually fuel that is not taking part of the injection or stems from a separate fuel line, i.e. shown in this example:

Fuel injectors not covered by F02M 47/02 and F02M 47/04.

Illustrative example of subject matter classified in this group.

E.g.: electrical wirings, pumps with electric plunger drive and injectors with electric needle drive (solenoid, piezoelectric etc.)

Injectors peculiar thereto, with electrical means directly or indirectly via a hydraulic or mechanical linkage operating the valve needle.

Illustrative example of subject matter classified in this group.

Injectors featuring hollow actuators, e.g. the needle passing through the hollow space. Example:

Illustrative example of subject matter classified in this group.

Illustrative example of subject matter classified in this group.

Illustrative example of subject matter classified in this group.

Illustrative examples of subject matter classified in this group.

Illustrative example of subject matter classified in this group.

Armatures having a valve attached thereto or integrated therewith.

Illustrative example of subject matter classified in this group.

Illustrative example of subject matter classified in this group.

Illustrative example of subject matter classified in this group.

Illustrative example of subject matter classified in this group.

The armature and the valve being allowed to move relatively to each other or not being attached to each other or at least part of valve being flexible.

E.g.:

Illustrative examples of subject matter classified in this group.

In cases where it cannot be easily determined whether the valve body attached to the armature is short or elongated both F02M 51/0667 and F02M 51/0671 should be used.

The armature having an elongated valve body attached thereto, or the armature having an elongated valve body integrated therewith, e.g. the armature constituting in itself an elongated valve body. Eg.:

E.g.:

In cases where it cannot be easily determined whether the valve body attached to the armature is short or elongated both F02M 51/0667 and F02M 51/0671 should be used.

The valve body having cylindrical guiding or metering portions, e.g. with fuel passages. E.g.:

Illustrative example of subject matter classified in this group.

Illustrative example of subject matter classified in this group.

In cases where it cannot be easily determined whether the valve body attached to the armature is short or elongated both F02M 51/0667 and the appropriate class/code F02M 51/0671+ should be used.

The armature and the valve being allowed to move relatively to each other or not being attached to each other or at least part of valve being flexible.

Example:

Injectors using electromagnetic operating means and permanent magnets

Illustrative example of subject matter classified in this group.

Illustrative example of subject matter classified in this group.

Fuel injection apparatus having heating, cooling or thermally-insulating means, including devices to influence the fuel temperature in injectors or common rails

E.g. fuel conduits between pump and injector, their coupling, constructional aspects of accumulators or common rails.

Venting means, i.e. for venting gases.

Specific arrangements or details of fuel passages inside injectors. E.g. or

Fuel injectors combined or associate with other devices, e.g. injectors combined with fuel pumps, injectors combined with sensors, injectors combined with engine valves, and injectors combined with plugs.

Pumps specially adapted for fuel-injection and not provided for in groups F02M 39/00 - F02M 57/00. For further subject-matter covered, see the section "Special rules of classification".

The structure of this group comprises:

Besides the subject-matter covered by the main group title, this place also covers details of the pumps classified in F02M 41/00, F02M 43/00, F02M 51/00.

Reciprocating piston type pumps with cylinders arranged radially to driving shaft, e.g. in V or star arrangement. "arranged radially" is interpreted to be understood as excluding in-line pumps.

Illustrative example of subject matter classified in this group.

Illustrative example of subject matter classified in this group.

Constructional parts (F02M 61/02-F02M 61/12) and a general, details part (F02M 61/16-F02M 61/205).

Fuel-injectors not provided for in groups F02M 39/00 - F02M 57/00 or F02M 67/00 having valves, e.g. having a plurality of valves in series.

Means for adjusting injection-valve lift during operation of the valve, in order to adjust it to the operating conditions and requirements of the moment.

Assembling; Disassembling; Manufacturing and Adjusting in the sense of calibrating during manufacture.

Discharge orifices arranged so that the jets are flowing therethrough at an angle to the normal axis of the injector.

Illustrative example of subject matter classified in this group.

Discharge orifices having variable cross section, e.g. divergent, convergent or stepwise changing cross section. E.g.:

E.g. the exact size, diameter is given, or a special relationship between a diameter and a length is given.

Most active subgroup in this group is F02M 63/0225 dealing with the common rails. The groups F02M 63/0003 - F02M 63/0008 include injection system having a fuel pressure source and an on/off valve in each fuel conduit to injector. These systems are different from accumulator type fuel injectors classified in F02M 47/02. Also these valves have different function than the control valves in the fuel injection pumps defined by the groups F02M 59/36-F02M 59/366.

Valves other than fuel injection valves, i.e. fuel injectors, whenever relevant.

Not to be used to characterise fuel injection valves, i.e. fuel injectors, unless they have pertinent characteristics or have details, component parts or accessories not provided for in F02M 61/00, F02M 51/06, or Indexing Codes F02M 2200/00.

The valves in F02M 63/0012 may be part of fuel injection apparatus for which there exist specific classes elsewhere, and which are thus classified both in that specific class and in F02M 63/0012, if the valve has a relevant feature per se.

The fixed armature is the magnetic core that does not move.

Illustrative example of subject matter classified in this group.

Illustrative example of subject matter classified in this group.

Illustrative example of subject matter classified in this group.

Valve unit controlling more than one function.

Valves that open when a specific pressure has been reached.

Testing of fuel injection apparatus.

Testing injection timing.

Measuring injector spray angle

Quality check of fuel-injection apparatus.

Monitoring the function of the fuel injection apparatus in situ, e.g. for monitoring injection timing or injection quantity, or malfunction detection.

These groups relate mostly to old technology, however there are some recent inventions. These groups can overlap with the group F02M 69/08. The classification can be made in both groups.

Low pressure fuel injection apparatuses including such apparatus with both continuous and intermittent injection, and apparatus injecting different types of fuel. Low pressure fuel injection normally means gasoline fuel injection. However in the recent years with common rail technology development the gap between diesel fuel injection and gasoline fuel injection has become very narrow. Therefore, it is more practical to classify the details of gasoline fuel injection apparatus just in the groups F02M 41/00-F02M 63/00. In specific cases and the injection of fuel in the air inlet manifold, the inventions are classified in the subgroups of F02M 69/00.

Low pressure fuel injection apparatuses means normally gasoline fuel injection. However in the recent years with common rail technology development the gap between diesel fuel injection and gasoline fuel injection has become very narrow. Therefore, it is more practical to classify the details of gasoline fuel injection apparatus just in the groups F02M 41/00-F02M 63/00. In specific cases and the injection of fuel in the air inlet manifold, the inventions are classified in the subgroups of F02M 69/00.

The injection nozzle opening into the engine cylinder for direct injection, i.e. in-cylinder injection.

One injector injecting fuel in the intake plus one injector injecting directly into the combustion chamber.