KR20010051615A - Method for operation of engine - Google Patents

Abstract

PURPOSE: A method for operating an engine is provided for discharging toxic material and reducing engine instability. CONSTITUTION: A method for operating engine has a combustion chamber(4) and involves directly injecting fuel into the combustion chamber(4) during the compression stroke in one function mode and in the induction stroke in a second mode. The engine(1) operates in the compression stroke injection mode when the engine is cold. A controller(18) controls switching function modes.

Description

How the engine works {METHOD FOR OPERATION OF ENGINE}

The present invention relates to an engine, in particular a method of operating a vehicle engine. Fuel is injected into the combustion chamber during the compression phase in the first mode of operation and during the intake phase in the second mode of operation, the two modes of operation being switched over. The present invention relates to a corresponding engine and a control device for this type of engine.

Such methods, engines and control devices of this type are known, for example, in fuel direct injection. In a fuel direct injection engine, fuel is injected into the combustion chamber of the engine during the intake phase in homogeneous operation and during the compression phase in stratified operation. Homogeneous operation is provided for full load of the engine, but stratified operation is suitable for idling and partial load of the engine.

Lamellar operation cannot be carried out without further measures, especially when the engine is cool. In stratified operation, when the engine is cooled, toxic emissions and engine instability are elevated.

It is an object of the present invention to achieve an engine operating method in which stratified operation can be carried out even when the engine is cooled.

This object is solved through the method according to the invention in which the injection is controlled and / or adjusted in accordance with the temperature in the first mode of operation when the engine is cooled. In the engine and control device of the type described above, the object of the invention is correspondingly solved according to the invention.

Through temperature control and / or adjustment, an improved warm up of the engine is achieved, in particular after a cold start of the engine. In particular, the operation quietness of the engine and the operation associated with the exhaust gas can be improved with temperature. In addition, the warm-up phase can be shortened so that the time of switching the engine to another operating mode can be shortened.

In an advantageous refinement of the invention, the transition to the first mode of operation when the engine is cooled is controlled and / or adjusted in accordance with the temperature. This means that not only the stratified operation but also the switching of the operating mode is performed according to the temperature as well. This also affects the timing and the transition process.

In an advantageous refinement of the invention, the injection timing and / or ignition timing are controlled and / or adjusted in accordance with the temperature, and / or the exhaust gas return ratio through the throttle valve angle and / or the exhaust gas return valve is controlled and controlled in accordance with the temperature. And / or adjusted.

In another advantageous refinement of the invention, the engine temperature and / or the exhaust air temperature and / or the exhaust gas temperature are measured.

What is important is that the method according to the invention is achieved in particular as a control element for a control device of a vehicle engine. The control element stores an executable program stored in a computing device, in particular a microprocessor, suitable for achieving the method according to the invention. In this case, since the present invention is accomplished by the above program stored in the control element, the control element provided with the program executes the present invention in the same manner as the above program suitable for carrying out the present invention. As the control element, in particular, an electrical storage medium such as read-only-memory or flash-memory can be used.

Other features, possibilities, and advantages of the invention can be seen through the embodiments of the invention described below. All features described or presented are formed on their own or in any combination different from the subject matter of the present invention, without departing from the specification, the description or the drawings.

1 is a schematic block diagram illustrating an embodiment of an engine according to the present invention.

<Explanation of symbols for main parts of drawing>

1: engine

2; piston

4: combustion chamber

5: intake valve

6: exhaust valve

7: intake pipe

8: exhaust pipe

10: injection valve

11: throttle valve

14; Exhaust gas return valve

15: fuel tank

16: fuel tank ventilation line

18: control device

22: temperature sensor

1 shows a vehicle engine 1 in which a piston 2 reciprocates in a cylinder 3. The cylinder 3 is provided with a combustion chamber limited by the piston 2, the intake valve 5 and the exhaust valve 6. An intake pipe 7 is connected to the intake valve 5 and an exhaust pipe 8 is connected to the exhaust valve 6.

In the region of the intake valve 5 and the exhaust valve 6, the injection valve 9 and the spark plug 10 protrude into the combustion chamber. Fuel is injected into the combustion chamber 4 through the injection valve 9. Fuel is ignited in the combustion chamber 4 by the spark plug 10.

A pivotable throttle valve 11 is arranged in the intake pipe 7, through which air can be supplied to the intake pipe 7. The amount of air supplied depends on the angle of the throttle valve 11. In the exhaust pipe 8 is arranged a catalytic converter 12 which is used to purify the exhaust gas generated through combustion of the fuel.

An exhaust gas return line 13 is guided from the exhaust pipe 8 to the intake pipe 7. An exhaust gas return valve 14 is disposed in the exhaust gas return line 13 to adjust the amount of exhaust gas returned to the intake pipe 8. The exhaust gas return line 13 and the exhaust gas return valve 14 return the exhaust gas.

The fuel tank ventilation line 16 is guided from the fuel tank 15 to the intake pipe 7. A tank ventilation valve 17 is disposed in the fuel tank ventilation line 16 so that the amount of fuel vapor introduced from the fuel tank 15 into the intake pipe 7 can be adjusted. The fuel tank vent line 16 and the fuel tank vent valve 17 ventilate the fuel tank.

The piston 2 is converted into a reciprocating motion, which is transmitted to a crankshaft not shown in the combustion chamber 4 to generate torque through combustion of fuel.

The control device 18 activates an input signal 19 representing the operating variable of the engine 1 measured by the sensor. For example, the control device 18 is connected to an air mass sensor, a lambda sensor, a speed sensor, and the like. In addition, the control device 18 is connected with an accelerator pedal sensor that transmits a signal that generates the required torque through the position of the accelerator pedal operable by the driver. The control device 18 generates an output signal 20 that can affect the operation of the engine 1 via an actuator or setter. For example, the control device 18 is connected to the injection valve 9, the spark plug 10 and the throttle valve 11 and the like to generate a signal necessary for control.

First of all, the control device 18 controls and / or adjusts operating parameters of the engine 1. For example, the amount of fuel injected from the injection valve 9 into the combustion chamber 4 is controlled and / or adjusted by the control device 18, in particular in view of low fuel consumption and / or low emissions of harmful substances. For this purpose, the control device 18 has a microprocessor which stores a program suitable for carrying out said control and / or adjustment in a storage medium, in particular flash memory.

The engine 1 of FIG. 1 can be operated in a number of operating modes. That is, the engine 1 can be operated by homogeneous operation, laminar operation, homogeneous lean operation, lean layer operation, and the like.

In homogeneous operation, fuel is injected directly into the combustion chamber 4 of the engine 1 by the injection valve 9 during the intake phase. This continues to vortex until the fuel is ignited, producing a substantially homogeneous fuel / air mixture in the combustion chamber 4. The generated moment is set by the control device 18 substantially via the position of the throttle valve 11. In homogeneous operation, the operating parameters of the engine 1 are controlled and / or adjusted so that the lambda equals one. Homogeneous operation is especially used at full load of the engine.

The homogeneous lean operation corresponds to the homogeneous operation, but lambda is set to less than one.

In laminar operation, fuel is injected directly into the combustion chamber 4 of the engine 1 by the injection valve 9 during the compression step. Thereby, a homogeneous mixer is not provided in the combustion chamber upon ignition through the spark plug 10, and a layer of fuel is formed. The throttle valve 11 is fully open except for example the need for exhaust gas return and / or fuel tank ventilation, whereby the engine 1 is operated without throttling. In stratified operation, the moment generated is set by the fuel amount. The engine 1 is operated in layered operation, especially at idle and partial loads.

The aforementioned operating modes of the engine 1 can be switched between each other. Switching in this manner is performed by the control device 18.

Also double injection is possible. That is, several fuel injections are performed to each combustion chamber 3 during the expansion stroke of the piston 2. This injection is carried out during the intake phase and / or the compression phase. Such multiple injections in particular represent an intermediate state, which switches between the operating modes described above.

According to the drawings a number of temperature sensors are provided. The temperature sensor 22 'is arranged in the area of the intake pipe 7 and measures the temperature to be sucked in. The other temperature sensors 22 &quot;, 22 &quot; '' are disposed in the white tube 80 region, i.e., before or after the catalytic converter 12. The other temperature sensors 22 &quot; '' are applied to the coolant or the engine and transmission oil. The engine temperature is determined via the temperature of the coolant or via the oil temperature At least one of the above-mentioned temperature sensors is provided In some cases, a plurality or all temperature sensors may be provided. The temperature sensor at is indicated by reference numeral 22.

When the engine 1 is in a cooled state, switching to stratified operation is controlled and / or adjusted in accordance with the temperature measured by the temperature sensor 22. Alternatively or additionally, the layered operation is controlled and / or adjusted in accordance with the temperature measured by the temperature sensor 22.

The control and / or adjustment according to the temperature corresponding to the engine 1 in the cooled state is based on the injection timing of the injection valve 9 and / or the ignition timing of the spark plug 10 and / or the angle and / or the throttle valve 11. Affects the exhaust gas return rate through the exhaust gas return valve. At least one of these operating variables is controlled and / or adjusted depending on the temperature. It is also possible to correspond correspondingly to many or all operating variables.

The influence on the operating parameters of the engine 1 in the cooled state is used for redundant injection in switching to and / or in stratified operation.

According to the present invention, there is provided a method of operating an engine in which layered operation can be carried out without further measures even when the engine is in a cooled state, thus reducing harmful substance emission and engine instability.

Claims (9)

In a method of operating an engine, in particular a vehicle engine, in which fuel is injected into the combustion chamber 4 during the compression step in the first mode of operation and during the intake phase in the second mode of operation, the two modes of operation are switched between each other, When the engine (1) is in a cooled state, the injection in the first mode of operation is controlled and / or adjusted according to the temperature. 2. Method according to claim 1, characterized in that when the engine (1) is in a cooled state, switching to the first mode of operation is controlled and / or adjusted in accordance with the temperature. 3. Method according to any one of the preceding claims, characterized in that the injection timing and / or the ignition timing are controlled and / or adjusted in accordance with the temperature. The method according to any one of claims 1 to 3, characterized in that the angle of the throttle valve 11 and / or the exhaust gas return ratio through the exhaust gas return valve 14 is controlled and / or adjusted in accordance with the temperature. How the engine works. 4. A method according to any one of the preceding claims, wherein the engine temperature and / or the intake air temperature and / or the exhaust gas temperature are measured. 6. The method of claim 5 wherein the coolant temperature and / or the oil temperature are measured. A control element for an engine, in particular for the control device 18 of the vehicle engine 1, in particular a program executable and stored in a computing device, in particular a microprocessor, suitable for achieving any one of claims 1 to 6. ROM or flash memory. Engine 1, in particular a vehicle, with fuel injected into the combustion chamber 4 during the compression phase in the first mode of operation and during the intake phase in the second mode of operation, with a control device 18 for switching between the two modes of operation. In the engine, A temperature sensor (22) is provided, characterized in that when the engine (1) is in a cooled state, the injection in the first mode of operation is controllable and / or adjustable in accordance with the temperature via the control device (18). An engine, in particular a vehicle, having a combustion chamber 4, in which fuel is injectable into the combustion chamber during the compression phase in the first mode of operation and during the intake phase in the second mode of operation and provided for switching between the modes of operation In the control device for the engine of, When the engine (1) is in the cooled state, the injection in the first mode of operation is controlled and / or adjustable in accordance with the temperature via the control device (18).