DE3136111A1 - Engine system with a reciprocating piston internal combustion engine - Google Patents

Description

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description

The invention relates to an engine system with a reciprocating internal combustion engine · 'With \ an air intake manifold and an exhaust manifold, one connecting the manifolds Conduit, a valve located in the conduit used to control the flow of exhaust gas into the air intake manifold is adjustable, and one. Fuel delivery facility for. Delivering fuel to the internal combustion engine.

The main purpose of exhaust gas recirculation is to reduce the level of harmful gases in the engine exhaust, generally with an increase in the fuel supply amount to the internal combustion engine, the amount of exhaust gas supplied to the air intake manifold at a given engine speed should decrease.

There are systems in which the setting of the valve is determined by a device that can be actuated by pressure medium pressure that responds directly or indirectly to a pressure medium pressure within the fuel delivery device, the changes when the amount of fuel supplied to the internal combustion engine changes changes. The disadvantage of such a system is the delay involved in setting the valve occurs following an increase in the amount of fuel supplied to the internal combustion engine. This leads to a weak Combustion of the fuel.

The object of the invention is to create an engine system of the specified type in a simple and expedient form, that of the above. Avoids disadvantage.

This object is achieved according to the invention by the Subject matter of claim 1..

Advantageous further developments of the invention are the subject of the subclaims.

In the following, exemplary embodiments of the invention are described with reference to the drawing. Show it:

1 shows a schematic view of the internal combustion engine with associated components;

Fig. 2 is a block diagram of part of an example of the engine system;

Figure 3 is a block diagram of part of another example the engine system;

FIG. 4 is a block diagram of a portion of that shown in FIG Motor systems.

According to Fig. 1, an engine system includes an internal combustion engine 10 with compression ignition including injection nozzles 11, which are connected to the respective outlets of a fuel injection pump 12 are connected, which is driven in a temporal relationship with the internal combustion engine 10. The fuel injectors direct the fuel into the respective combustion chambers of the internal combustion engine. The internal combustion engine also has an air intake manifold 13 and an exhaust manifold 14, which are connected to one another via a line 15. In A valve 16 is arranged in line 15, the setting of which is controlled by a servomotor 17. Operational opening valve 16 allows exhaust gas to flow from the exhaust manifold into the air intake manifold in a known manner Control of the production of harmful gases during the operation of the internal combustion engine.

In FIG. 2, the valve 16 is together with its servomotor 17 shown with the fuel injection pump 12. The servomotor 17 is generated by a signal at the output of a comparator 18

delivered signal controlled. The comparator 18 receives a Signal from a MAP represented by a block 19. Of the MAP receives two inputs and provides an appropriate signal to the comparator indicating the desired position of the valve indicates. For this purpose, an engine speed signal and additionally a signal 21 for the actual Motor fuel ·. delivered. .MM ».contains the saved Information regarding the specific internal combustion engine.

The fuel signal 21 represents the actual amount The fuel supplied to the internal combustion engine is represented by a converter and a decoding circuit (not shown) derived, the converter from the fuel injection pump will be carried. A fuel control signal 31 becomes Fuel injection pump supplied by a control loop which includes a circuit block 22 to be described and an operator demand signal from a converter 23 and also the engine speed signal from converter 20 .. The effect of circuit block 22 is to generate an appropriate fuel tax signals 31 according to the demand and the engine speed. So that the maximum delivered to the internal combustion engine Fuel quantity does not exceed a given value, a maximum fuel MAP 24 is provided which is the engine speed signal and receives a maximum fuel signal or limit signal to circuit block 22 supplies. This limit signal can be modified by a further block 25 to be described. The fuel control signal 31 is used to determine the setting of the fuel control member the fuel injection pump 12. The circuit block 22 is also used to control the maximum speed of the associated internal combustion engine and also the idling speed. The fuel signal 21 and also the engine speed signal received from the converter 20 are represented by a block 26 provided further MAP. This block 26 delivers from the stored information about the fuel injection pump

a signal that controls the timing of fuel delivery determined for the associated internal combustion engine.

The other input to the comparator 18 in the example of Fig. is a correction signal received from a converter 27 which supplies a signal representing the fresh air flow to the internal combustion engine. This converter is therefore in the Air inlet manifold 13 is arranged upstream of its connection to line 15. Between the converter 27 and the comparator 18 there is a circuit block 28 which changes the signal according to the ventilation density. That the airflow The signal representing the circuit is also supplied to the circuit block 25. The effect of this is that the maximum Amount of fuel delivered to the internal combustion engine and provided by the MAP 24, modified by the actual air flow to the engine will. Even if the operator of the internal combustion engine suddenly increases the demand for the internal combustion engine consequently the fuel flow to the internal combustion engine accordingly controlled by the air flow to the internal combustion engine. As the airflow increases, so does the amount of fuel delivered to the internal combustion engine. A limit is imposed by the MAP 24 which ensures that no more than that permissible maximum fuel quantity of the internal combustion engine in Depending on the speed of which is supplied.

The circuit block 22 includes, as shown in FIG. 4, a comparator 32, from the output of which the fuel control signal is obtained, one input of which is the signal for the actual fuel derived from the decoding circuit connected to the converter carried by the fuel injection pump. The other input of the comparator is connected to the output of a limiting circuit 33 ^that: receives signal from the circuit block 25 and whose input is connected to the output of a fuel demand calculation circuit of the engine speed signal from the transducer 20

and the operator demand signal. receives from converter 23. The fuel requirement calculation circuit 34 takes the engine speed into account in order to limit the maximum engine speed Execute control function.

In the arrangement of Fig. 3, parts having the same function have the same reference numerals as in Fig. 2. The converter 27 is omitted. In its place, a converter 29 is provided, which provides an indication of the position of the valve 16. Of the The output of the converter 29 is passed through a block 30, which ensures that the signal supplied to the comparator 18 represents the air flow to the internal combustion engine. The arrangement of FIG. 3 is possible in connection with an internal combustion engine with compression ignition, since at a given engine speed the total volume of what is sucked into the internal combustion engine Air-exhaust gas mixture is essentially constant, so that the volume of sucked into the internal combustion engine Fresh air can be determined by observing the position of the valve 16.

The systems of Figures 2 and 3 can be modified by modifying the output of the comparator 18 according to the differential of that from the converter 23 can be changed. So if a rapid change in demand is carried out, there is a rapid change in the position of valve 16. When described. In the same system, analog, digital, or both techniques can be used, depending on the expediency.

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Claims (5)

Expectations Engine system with a reciprocating internal combustion engine, marked ic h η e t - through an air intake manifold (13) and an exhaust manifold (14), - By a line connecting the bends (13, 14) (15) with a valve (16), - by an electrical controller to control the setting the valve (16) for controlling the flow of exhaust gas into the air intake manifold (13), - by a fuel delivery device (12) for delivery from fuel to the internal combustion engine (10), - By an electrical control device for controlling the operation of the controller, - by a device for supplying an electrical signal representing the air flow to the internal combustion engine (10), - The electrical control device for determining the setting of the valve (16) to the signal and on the engine speed and that of the internal combustion engine responds to signals representing the amount of fuel delivered, and 67-102009 T - by another device for controlling the through the fuel delivery device (12) for. Internal combustion engine (10) the amount of fuel supplied, - where the further device responds to the signal, whereby the maximum amount of fuel that can be delivered to the internal combustion engine (10) from the air flow to the internal combustion engine (10) depends. 2. System according to claim 1,
characterized, - That the further device has a control loop with - a first circuit device responsive to operator demand ssignal and an engine speed signal is responsive for providing a fuel demand signal to the fuel delivery device (12), - A second circuit device for supplying a Fuel limit signal to the first circuit device, wherein the fuel limit signal depends on the engine speed, as a result of which the maximum amount of fuel that can be delivered to the internal combustion engine (10) depends on the engine speed, and - a third responsive to the electrical signal Circuit device for changing the limit signal so that the one that can be supplied to the internal combustion engine (10) maximum amount of fuel also depends on the air flow to the internal combustion engine (10). 3. System according to claim 1 or 2,
characterized, - that the electrical control device contains: - an electrical comparator, the output of which is connected to the controller, - A first input to the comparator, which is switched in this way is that he receives the electrical signal, and - Another circuit device which is connected to a second input of the comparator, and - That the further circuit device receives signals relating to the engine speed and those relating to the internal combustion engine (1.0) indicate the actual amount of fuel delivered, and on the basis of these signals a signal to the second The input of the comparator supplies which indicates the desired setting of the valve (16). 4. System according to claim 1,
marked, - through a converter for delivering the air flow to the internal combustion engine (10) representing signal and - by a device for modifying the signal accordingly 'the air density, - the converter being upstream of the duct (15) in the air intake manifold (13) is arranged and the output of the device is the electrical signal. 5. System according to claim 1, ■ characterized - That the internal combustion engine (10) with compression ignition operates and a converter for supplying a signal indicating the setting of the valve (16) and a Has means for modifying the signal at least as a function of an engine speed signal, so that the output of the device is the air flow to the internal combustion engine (10) and forms the electrical signal.