DE2343203A1 - FUEL INJECTION SYSTEM - Google Patents

Description

COHAUSZ & FLORACK

PAT B NT AN WALT S OFFICE 4 DÜSSELDORF SCHOMANNSTR. 97

PATENT LAWYERS: Dipl.-lng. W. COHAUSZ Dipl.-Ing. W. FLORACK Dipl.-Ing. R. KNAUF · Dr.-lng., Dipl.-Wirtsch.-lng. A. GERBER

C.A.V. Liiüited

Veil Street

Birmingham / England August 24th 1973

Fuel injection system

The invention relates to a fuel injection system for an internal combustion engine; fcpjr> i t $ 5i% ^ i ^ e ^ KrafvtgtQfcßeinspritzdüse for arrangement on an engine in such a way that fuel is directed into a combustion chamber of the engine, the fuel injection nozzle having a valve element which is in a closed position to prevent the flow of fuel to the engine is biased, but is opened by the action of the fuel at a target pressure at an inlet of the nozzle.

The invention is based on the object of making such a system in a simple and appropriate form.

According to the invention, the system has a valve for regulating the supply of fuel under pressure to the inlet, with the valve on the pressure prevailing in the combustion chamber responds, wherein means for supplying a controlled amount of fuel to the inlet via said Valve are provided.

The invention is shown below on the basis of an exemplary embodiment With reference to the drawing explained in more detail, in which the system is shown schematically in application to a three-cylinder diesel engine.

In the drawing, the engine is shown at 10 and it is with cylinders 11 veersehen, in which pistons 12 sit, which in a known V / eise with a crankshaft of the engine are connected. Each cylinder is with

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409810/0494 ⁰ ^ GfNAL inspected

an air inlet and an outlet valve, both not shown are, and the es-um over deia piston forms a combustion chamber in the fuel is burned in a lux charge in the known 61st eice.

A fuel injector I5 is assigned to each cylinder, and each Nozzle has a spring-loaded valve el em ent I4 ε-uf, which is known in is designed to allow the flow of fuel through openings 15 to control in the associated combustion chamber. liie nozzle is ax an inlet 16 through which fuel under pressure to the nozzle can flow, and the arrangement is such that when the Fuel reaches a target pressure, the valve element 14 pen from the seat the action of the spring force on it lifts to a flow to allow fuel through the openings 15.

Each inlet 16 is provided with lines to the outlet 17 of a source 10 for Fuel connected under pressure. This source includes a fuel pump which is driven in synchronism with the engine so that it supplies fuel at certain times while the engine is running. It also has means by which the amount and timing of the supply of fuel can be adjusted.

The fuel flow to the individual nozzles is controlled by the relevant Valve 19 controlled. Each valve 19 has a spring-loaded valve member 20 shows that in the closed position there is a flow of fuel from the outlet 17 of the source to the associated nozzle. In the open position, the flow of fuel can proceed like that has been said above. Each valve member 20 is assigned an actuating member, expediently in the form of a membrane 21, which is exposed to the pressure that prevails in the associated combustion chamber. The membrane 21 acts against a thrust member 22 which is integral with the valve member is trained. The tree on the far side of the membrane opposite the combustion chamber is ventilated to a low pressure.

The arrangement is such that the associated valve 19 opens only when if the pressure in the combustion chamber assumes a certain value, then if

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SAD ORIGINAL

the compression stroke of the piston takes place. The valve members of the remaining valves 19 are in the closed position, see above daö the fuel supplied by the source 18 only to the nozzle 1J of the ijlinders flows, whose piston performs the compression stroke. As above mentioned, the flow of fuel from the source is dependent on time to the engine and when the pressure of the fuel reaches a target value, the valve element 14 of the relevant nozzle 15 opens to allow fuel to flow into the combustion chamber to prevent.

Expectations

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Claims (4)

Expectations 1. Fuel injection system for an internal combustion engine, with a Fuel injector for placement on an engine in such a manner that fuel is directed into a combustion chamber of the engine; wherein the fuel injector has a valve element that is in a closed position to prevent an inflow of fuel is biased to the engine, but by the action of the fuel is opened at a target pressure at an inlet of the nozzle, thereby characterized in that the system includes a valve for regulating the supply of fuel under pressure to the inlet, the valve is responsive to the pressure in the combustion chamber, means for supplying a controlled amount of fuel to the inlet via said valve are provided. 2. System according to claim 1, characterized in that the valve having a valve element and a seat and spring means epannen the valve element against the seat, a membrane from the pressure in the Combustion chamber of the engine is acted upon so that a movement of the valve element caused against the action of the spring means away from the seat will. 3. System according to claim 2, characterized in that the means for Supply of fuel have a fuel pump that supplies fuel at certain times during the running of the engine. 4. System according to claim 3, characterized by a plurality of fuel injection nozzles and respective valves by which the nozzles are supplied with fuel from the single pump. 409810/0494