DE2452951A1 - COMBUSTION MACHINE - Google Patents

Description

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η.
October 28, 1974 Su / Kb

Annex to the patent and utility model registration

ROBERT BOSCH GMBH, Stuttgart

Internal combustion engine

The invention relates to an internal combustion engine with a main combustion chamber arranged above the piston, the inlet of which is controlled by a motorized valve before opening of the valve, fuel is stored upstream and connected to the main combustion chamber by an overflow opening Pre-combustion chamber, which contains an ignition device and an inlet of fuel or fuel-air mixture has controlling valve, which is operated synchronously with the engine valve.

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609820/0536

2452351

It is known that a fuel-air mixture must have 10 to 15 % fuel content in order to be easily ignitable, with the highest engine output being achieved at the same time. In contrast, poorer mixtures, which would be desirable in view of the significantly lower content of toxic exhaust gases, are more difficult to ignite. For this reason, internal combustion engines with a pre-combustion chamber have been developed. A rich fuel-air mixture is ignited in the pre-combustion chamber, as a result of which a jet flame develops towards the main combustion chamber, which then serves to ignite the lean, more difficult-to-ignite mixture in the main combustion chamber. The result is a significant reduction in pollutants in the exhaust gas with lower fuel consumption at the same time.

In such systems, the fuel supply required, separate from the pre-combustion chamber and the main combustion chamber, takes place as is well known, either in the intake manifolds of the combustion chambers or directly in the combustion chambers. The feed directly into the Combustion chambers are usually carried out via injection systems that work with a correspondingly high delivery pressure and are very expensive in terms of cost. In addition, there are also not inconsiderable problems for the preparation of the fuel-air mixture in the combustion chambers of such direct injectors. The same is essentially true of procedures; in which the main combustion chamber is already supplied with the fuel-air mixture via the engine inlet valve, while is injected directly into the pre-combustion chamber. Even internal combustion engines in which the fuel supply is in the Intake pipes of the combustion chambers require, for example, two separate carburetor systems when using carburetors, but which have to work synchronously.

The invention is based on the object of developing an internal combustion engine of the type mentioned at the outset, in which A minimum of effort is necessary for the distribution of the fuel quantities to the main combustion chamber and pre-combustion chamber, whereby also for the fuel metering per engine cylinder

60982Ö / 0S36 -3-

only one fuel metering system is required.

This object is achieved according to the invention in that Engine valve and intake valve have a common movable valve part, which is one in the valve seat surface of the Engine valve arranged opening controls, which is connected to the pre-combustion chamber, preferably as Serve opening bores which open into an annular channel which is arranged parallel to the seat and which passes through a suction channel is connected to the pre-combustion chamber. As soon as the engine valve opens, a very high negative pressure is generated in the gap between the movable valve part and the valve seat. This negative pressure is transmitted through the bores into the pre-combustion chamber, which then causes this negative pressure to flow through the overflow opening the very rich fuel-air mixture that first enters the main combustion chamber is sucked into the pre-combustion chamber. Valve port and bores act on the principle of a water jet pump. After completion of the intake stroke of the internal combustion engine there is a significantly richer and therefore more ignitable mixture in the pre-combustion chamber than in the main combustion chamber. Ignition then takes place via the spark plug in the pre-combustion chamber and from the pre-combustion chamber through the Overflow opening in the main combustion chamber.

An embodiment of the subject matter of the invention is shown in the drawing and will be described in more detail below described.

In the cylinder head 1 of a stratified charge internal combustion engine, an engine intake valve 2, an injector 3 and a Pre-combustion chamber 4 arranged. The pre-combustion chamber 4 into which a spark plug 5 protrudes, is connected to the main combustion chamber 7 of the internal combustion engine through an overflow opening 6, which by the engine piston 8, the cylinder 9 and the

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b U 9 8 2 0/0 5 3 6

Cylinder head 1 is limited. The engine valve 2 has a valve disk 11 which cooperates with a stationary seat 12. The seat 12 is arranged on a ring 13 which, with the cylinder head 1, encloses an annular channel 14. from the seat 12 lead to the annular channel 14 holes 15, which are controlled by the valve disk 11. A suction channel 17 leads from the annular channel 14 to the pre-combustion chamber 4 and there opens into an annular space 18 arranged coaxially to the spark plug 5.

The engine intake valve 2 is supplied with fuel via the injection nozzle 3 upstream, which then occurs during the suction stroke of the piston 8 and after the valve disk 11 has been opened into the main combustion chamber 7 is sucked. In the annular gap formed between valve disk 11 and valve seat 12, a high flow velocity is created, due to the principle of the water jet pump via the bores 15 and the suction channel 17 a particularly high negative pressure is set in the pre-combustion chamber. Because of this negative pressure, part of the too The beginning of the very rich air mixture entering the main combustion chamber is sucked into the antechamber 4 via the overflow opening 6. This same overflow opening then serves as a flame duct during the combustion stroke of the internal combustion engine in which the rich mixture has been ignited in the prechamber 4 via the spark plug 5 and the flame jet via the overflow opening 6 reaches the main combustion chamber 7 in order to ignite the lean fuel-air mixture there.

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60982Ö / 0G36

Claims (4)

Claims «, £ ■ 4 A f IJ internal combustion engine with one arranged above the piston Main combustion chamber, the input of which is controlled by an engine valve, upstream of the fuel before opening the valve and with one through an overflow opening to the main combustion chamber connected pre-combustion chamber, which contains an ignition device and an inlet of fuel or Has the fuel-air mixture controlling valve which is actuated synchronously with the engine valve, characterized in that, that the engine valve (2) and control valve (15) of the pre-combustion chamber are a common movable valve part (11) which controls an opening (15) arranged in the valve seat surface (12) of the Mötör valve, which opens with the Pre-combustion chamber (4) is connected. 2. Internal combustion engine according to claim 1, characterized in that bores (15) serve as the opening, which in a parallel to the seat (12) arranged annular channel (14) open through a suction channel (17) is connected to the pre-combustion chamber (4) 3. Internal combustion engine according to claim 2, characterized in that the suction channel (17) in a particular concentric the annular space (18) arranged around the ignition device (5) opens. -6- 609820/0536 Z 4 ί - 4. Internal combustion engine according to claim 2 or 3, characterized in that that the annular channel (14) between an insert ring carrying the valve seat (12) and containing the bores (15) (13) and the cylinder head (1) is formed. 609820/0536