KR19990003451A - Engine afterburn prevention method and device - Google Patents

Abstract

The present invention provides a method and an apparatus for preventing post-combustion of an engine for correcting an ignition timing and a fuel injection amount to prevent damage of an exhaust gas purifying device due to a post-combustion flame by suppressing post-combustion due to aging of the spark plug or lack of intake. A first process of detecting the amount of flame discharged from the combustion chamber through an optical sensor installed in the exhaust manifold of the engine, a second process of determining whether the detected amount of flame is greater than a threshold value, and the determination result And a third step of correcting the ignition timing of the ignition device and the fuel injection amount of the fuel supply device when the amount is greater than or equal to the threshold value.

In an engine that obtains power by burning with a spark plug of an ignition device in a state in which a mixture of fuel and air supplied from a fuel supply device and an intake device to a combustion chamber is compressed, the engine is installed in an exhaust manifold through which the combustion gas of the combustion chamber is discharged. And an optical sensor for detecting the amount of flame emitted from the combustion chamber, and an engine ECM for detecting the amount of flame through the optical sensor to determine the post-combustion and prematurely ignite the ignition timing of the ignition device. Provide afterburn prevention device.

Description

Engine afterburn prevention method and device

The present invention relates to a method and a device for preventing post-combustion of an automobile engine, and more particularly, to determine the post-combustion by detecting the flame amount of an exhaust manifold due to aging of the spark plug or lack of intake air. The present invention relates to an engine post-combustion prevention method and apparatus for correcting an ignition timing or fuel injection amount during combustion to suppress post-combustion and to prevent damage to an exhaust gas purifying device caused by a post-combustion flame.

In general, the engine of an automobile is to obtain power by burning fuel compressed at high temperature and high pressure in a combustion chamber. Among the engines that are currently widely used, gasoline engines using gasoline as a fuel and diesel fuel are used as fuel. It is roughly classified as a diesel engine.

Here, the gasoline engine compresses the fuel to a state of high temperature and high pressure in the combustion chamber formed between the cylinder and the cylinder head and the piston reciprocating in the cylinder, and then burns by electric spark ignition, and occurs in the combustion process The mechanical force is obtained from thermal energy by rotating the crankshaft through the connecting rod connected to the piston.

That is, as shown in FIG. 1, the cylinder head 102 of the engine 100 includes an intake valve 104 for providing a mixture of fuel and air to be combusted in the combustion chamber 103, as shown in FIG. 1. The suction mixer is provided with a spark plug 130 for igniting a flame and an exhaust valve 105 provided for discharging the burned gas. That is, the intake valve 104 and the exhaust valve 105 are to be opened and closed by the valve opening and closing mechanism 120 connected to the crankshaft 115, the spark plug 130 in the ignition coil not shown It is to be able to generate an electric spark by the generated high-voltage current.

On the other hand, the engine 100 usually forms a plurality of cylinders (101a) in one cylinder block 101 and can harmonize the power generated in each combustion chamber 103 to draw a stable rotational force to the crankshaft (115) Make sure In addition, when the engine 100 performs a series of processes such as suction stroke, compression stroke, explosion stroke, and exhaust stroke by inhaling a mixer in which air and fuel are mixed, the stroke that substantially generates power in the engine 100 is performed. The ignition timing, which is the point of initiation of fuel combustion of the explosion stroke, acts as a major factor to enable harmonious operation and efficient operation of the engine 100.

As described above, the ignition timing is controlled by the distributor, and in the distributor, the rotation angle of the engine crankshaft 115 may be adjusted so as to provide an ignition timing suitable for the operation state continuously in synchronization with the engine in various operation states. The information is transmitted directly to the drive shaft of the distributor, and the ignition timing is adjusted to advance or perceive the ignition timing by a mechanical method.

However, when the ignition plug 130 is aged or damaged due to combustion gas or combustion heat of the combustion chamber 103, the ignition flame is weak or delayed, and thus the mixer in the compressed state cannot be ignited at the optimum ignition time. Accordingly, the mixer of the combustion chamber 103 undergoes post-combustion at the time when the exhaust valve 105 is opened, and thus the combustion gas in which the post-combustion proceeds is not completed in combustion, so the exhaust manifold 102a is accompanied by a flame. There is a problem in that the purifier installed in the exhaust pipe communicating with the exhaust manifold 102a, in particular, the three-way catalyst is overheated while being discharged to the exhaust manifold (102a).

In addition, even when the intake air is insufficient compared to the injection amount of the fuel, there is a problem that the ignition timing is also delayed to damage the purifier by generating the post combustion as described above.

Therefore, the present invention has been made in view of the above problems, the engine after-burning to prevent the damage of the exhaust gas purifier according to the after-burning flame by suppressing the post-burning due to aging of the spark plug or lack of intake It is an object of the present invention to provide a prevention method and an apparatus thereof.

1 is a partial cross-sectional view showing a one-time automobile engine

Figure 2 is a block diagram showing the configuration of the engine afterburn prevention device according to an embodiment of the present invention

3 is a flowchart illustrating an operation control process according to an embodiment of the present invention.

Explanation of symbols on the main parts of the drawings

1: engine 1a: combustion chamber

2b: Intake manifold 1c: Exhaust manifold

10: engine ECM 34: fuel supply unit-injector

40: ignition device-spark plug 50: light sensor

51: heating coil

The present invention for achieving the above object, the first process of detecting the amount of sparks discharged from the combustion chamber through an optical sensor installed in the exhaust manifold of the engine, and the second to determine whether the detected amount of sparks is greater than the threshold value And a third step of correcting the ignition timing of the ignition device and the fuel injection amount of the fuel supply device when the spark amount is greater than or equal to the threshold as a result of the determination;

In an engine that obtains power by burning with a spark plug of an ignition device in a state in which a mixture of fuel and air supplied from a fuel supply device and an intake device to a combustion chamber is compressed, the engine is installed in an exhaust manifold through which the combustion gas of the combustion chamber is discharged. And an optical sensor for detecting the amount of flame emitted from the combustion chamber, and an engine ECM for detecting the amount of flame through the optical sensor to determine post-combustion and prematurely ignite the ignition timing of the ignition device. It provides an engine afterburn prevention device.

Hereinafter, an embodiment of the present invention will be described in more detail with reference to the accompanying drawings.

2 is a block diagram showing a configuration of an engine post-combustion prevention apparatus according to an embodiment of the present invention, in which fuel supplied from a fuel tank 30 of a fuel supply device through a fuel pump 31 is supplied to a combustion chamber of an engine 1. An injector 34 for injecting in 1a, an ignition plug 40 of an ignition device for igniting fuel injected from the injectors 34, a coolant temperature sensor 11 for detecting a temperature of the coolant, The throttle position sensor 21 which detects the opening degree of the throttle valve 20, that is, the degree of the accelerator pedal being stepped down, and the MAP sensor 12 which indirectly detects the intake air amount according to the vacuum variation of the intake manifold 1b (manifold) an absolute pressure sensor), a crank angle sensor 41 for detecting a rotation angle of the crankshaft rotated in conjunction with the piston 1d, and an exhaust manifold 1c through which the combustion gas of the combustion chamber 1a is discharged. Light beam sensing the amount of flame emitted from the combustion chamber 1a The engine 50 is largely comprised of an engine electronic control module (ECM) 10 that controls each drive unit through the sensors.

That is, the engine ECM 10 determines the acceleration and deceleration of the vehicle through information input from the throttle position sensor 21, the crank angle sensor 41, the coolant temperature sensor 11, the MAP sensor 12, and the like. The fuel injection amount and the injection timing through the injector 34 of the fuel supply device are determined, and the ignition plug 40 of the ignition device is determined.

In particular, the engine ECM 10 detects the amount of flame through the optical sensor 50 to determine the post-combustion and to prematurely ignite the ignition plug 40 of the ignition device after the post-combustion, The injector 34 reduces the fuel injection amount.

On the other hand, on one side of the optical sensor 50 is provided a heating coil 51 to remove the exhaust gas particles formed in the light transmitting portion of the optical sensor 50, that is, soot.

In the drawings, reference numeral 22 denotes an air filter for filtering impurities of intake air supplied to the combustion chamber 1a through the intake manifold 1b, and 32 denotes the injector 34 through the fuel pump 31. Is a fuel filter for filtering impurities in the fuel supplied to the fuel cell, and 33 denotes an intake manifold for the pressure of the fuel applied to the injector 34 to maintain a constant fuel injection amount in response to the pressure change of the intake manifold 1b. The fuel pressure regulator adjusts the pressure higher than the pressure of the fold 34 to return to the fuel tank 30 through the fuel return line when the fuel pressure exceeds the set pressure.

As illustrated in FIG. 3, an operation according to an embodiment of the present invention configured as described above will be described according to an operation control process of the engine ECM 10.

First, the engine ECM 10 detects the amount of flame discharged from the combustion chamber 1a through the optical sensor 50 provided in the exhaust manifold 1c of the engine in step S101, and advances to step S102. In step S102, it is determined whether the detected flame amount is greater than or equal to a threshold value, and when the determination result is that the flame amount is greater than or equal to the threshold value, that is, after combustion, the operation proceeds to step S103 to early the ignition timing of the ignition device, and the early ignition is performed for a predetermined time ( Hold during T1).

As described above, when the early ignition passes the predetermined time T1, the flow proceeds to step S104 to detect the amount of flame discharged from the combustion chamber 1a through the optical sensor 50 again, and proceeds to step S105 to detect the result. It is determined whether the amount of sparks that has been fired is above a threshold. That is, it is confirmed whether the cause of the post combustion is the aging of the spark plug 40. As a result of the determination, if the flame amount is greater than or equal to the threshold value, the post-combustion is not solved, that is, the spark plug 40 is not the cause of aging. Therefore, the flow proceeds to step S106 to determine that the intake amount is insufficient. Reduce during (T2).

When the fuel injection amount reduction time has elapsed as described above, the flow proceeds to step S107, and again, the amount of sparks discharged from the combustion chamber 1a is detected again through the optical sensor 50, and the flow proceeds to step S108. It is judged whether the detected flame amount is more than a threshold value. In other words, it is determined again that the cause of the post-combustion is only the fuel injection amount according to the intake air, and as a result, when the spark amount is more than the threshold value, the ignition timing of the ignition device is premature and the fuel injection amount of the fuel supply device is reduced. Let's go.

Accordingly, in the present invention, when the cause of the post-combustion is due to premature ignition of the ignition plug 40, the combustion of the mixer is caused by the weakening of the ignition plug 40 or the delay of the spark generated from the ignition plug 40. It is possible to prevent the post-combustion, and when the post-combustion due to the lack of the intake air amount can also prevent the post-combustion by reducing the fuel injection amount.

In addition, when the post-combustion is not only one cause of aging of the spark plug 40 or insufficient intake air amount, the post-combustion can be more surely overcome by simultaneously correcting the ignition timing and the fuel injection amount.

As described above, the present invention detects the flame amount of the exhaust manifold due to the aging of the spark plug or the lack of intake air to determine the post combustion, and to control the post combustion by correcting the ignition timing or fuel injection amount during the post combustion. It is useful to prevent damage to the exhaust gas purification device due to the post combustion flame.

While the invention has been shown and described with respect to particular embodiments, it will be understood by those skilled in the art that various modifications and changes can be made without departing from the spirit and scope of the invention as indicated by the appended claims. Anyone can grow up easily.

Claims (5)

A first process of detecting an amount of flame discharged from the combustion chamber 1a through an optical sensor 50 installed in an exhaust manifold 1c of the engine, a second process of determining whether the detected amount of flame is greater than or equal to a threshold value, And the third step of correcting the ignition timing of the ignition device and the fuel injection amount of the fuel supply device when the spark amount is greater than or equal to the threshold value. The method of claim 1, wherein the third process comprises the step of prematurely igniting the ignition time for a predetermined time when the spark amount is greater than or equal to the threshold value, and after the predetermined time elapses, the combustion chamber (50) through the optical sensor 50 again. Detecting the amount of flame discharged from 1a), determining whether the detected amount of flame is greater than or equal to a threshold value, and if the result is that the amount of flame is greater than or equal to the threshold value, reducing the amount of fuel injected by the fuel supply device for a predetermined time; Detecting the amount of flame discharged from the combustion chamber 1a again through the optical sensor 50 after the predetermined time has elapsed; and determining whether the detected amount of flame is greater than or equal to a threshold value; Reducing the amount of fuel injected by the fuel supplying device at the same time as the ignition timing of the ignition device when the spark amount is above the threshold; How to prevent combustion engine, characterized in that. In an engine that obtains power by burning with a ignition plug 40 of an ignition device in a state in which a mixture of fuel and air supplied from a fuel supply device and an intake device to the combustion chamber 1a is compressed, the combustion gas of the combustion chamber 1a Is installed in the exhaust manifold (1c) to discharge the light sensor 50 for detecting the amount of flame emitted from the combustion chamber (1a) and the amount of flame through the light sensor 50 to determine the post-combustion The engine post-combustion prevention apparatus further comprises the engine ECM (10) which makes the ignition timing of the said ignition device early on combustion. The engine post-combustion prevention apparatus according to claim 3, wherein the engine ECM (10) drives the fuel supply device to reduce the injection amount of fuel during the post-combustion. 4. The apparatus of claim 3, wherein a heating coil (51) is provided on one side of the optical sensor (50) to remove exhaust gas particles formed in the optical sensor (50).