JPS6146446A - Suppressing method and device of knocking in spark-ignition internal-combustion engine - Google Patents

Abstract

PURPOSE:To prevent an engine from decreasing its output, by injecting knocking suppressing fluid to be supplied to a combustion chamber when knocking is detected and decressing an advance angle of the ignition timing when the knocking is still detected even after it is first detected. CONSTITUTION:When an engine is driven in operation, a control device 25 first calculates an optimum ignition timing advance angle on the basis of the output of a rotary angle sensor 46 and an intake air pressure sensor 42. Next the engine 1 is in operation within a predetermined speed range with cooling water at a predetermined temperature or more, and if the generation of knocking is detected by a knocking sensor 44, the opening of a flow control valve 26, interposed in a route where alcohol 30 having used as the knocking suppressing fluid is added to fuel in a supply fuel pipe 20, is increased in a fine degree step by step till the knocking disappears. And an ignitor 47 is controlled for decreasing the advance angle of the ignition timing only when the knocking is detected still after the valve 26 is fully opened.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a spark ignition internal combustion TFI 130, and more particularly to a method and apparatus for suppressing knocking in a spark ignition internal combustion engine.

BACKGROUND OF THE INVENTION In general, in spark-ignition internal combustion engines, so-called knocking, which generates large vibrations and knocking noises, may occur due to rapid combustion of end gas. It has been known that it is effective to inject and supply a knocking suppressing liquid such as water, alcohol, or a mixture thereof into the combustion chamber of an internal combustion engine as one method for suppressing the occurrence of such knocking. For example, some examples of such methods and apparatuses are disclosed in Japanese Patent Application No. 1983.
No.-46938, Patent Application No. 1983-46939, Utility Model No. 1983
5-94450, Japanese Patent Application Laid-Open No. 57-181957, etc., 1 m is shown.

Problems to be Solved by the Invention However, in these conventional methods and devices, when the internal combustion engine is operated under operating conditions where knocking is likely to occur, a predetermined amount of knock suppressing fluid corresponding to the operating conditions is used. Since the fuel is injected into the combustion chamber, the amount of knocking suppressing liquid consumed is relatively large, and as a result, the reservoir tank that stores the knocking suppressing liquid has to be tilted to a large extent.

In addition, as one of the conventional knocking suppression methods, Japanese Patent Application No. 56-1441 filed by the same applicant as the present applicant
As disclosed in No. 99, when knocking occurs, the ignition timing advance angle is reduced, and when knocking occurs even though the ignition timing advance angle has been reduced to a predetermined value, the ignition timing advance is reduced. It is already known to inject anti-knock liquid into the combustion chamber without reducing the angle beyond the predetermined value. However, in such a method, when knocking occurs, the advance angle of the ignition timing is first reduced, which reduces the thermal efficiency of the internal combustion engine and reduces the engine output.In particular, the intake air is not supercharged by the turbocharger. In internal combustion engines, an increase in the exhaust gas temperature by 2 may have an undesirable thermal effect on the turbocharger.

SUMMARY OF THE INVENTION In view of the above-mentioned problems in conventional methods and devices for suppressing knocking, it is an object of the present invention to provide a method and device for suppressing non-knocking for a spark ignition internal combustion engine that does not cause such problems.

Means for Solving the Problems According to the present invention, knocking is detected by a knocking sensor, and when knocking is detected by the knocking sensor, knocking suppressing fluid is injected and supplied to the combustion chamber of an internal combustion engine. After that, when knocking is detected by the knocking sensor, the knocking suppressing fluid injected and supplied to the combustion chamber is increased by ffi, and the knocking suppressing fluid is injected and supplied to the combustion chamber at the maximum supply. A method for suppressing knocking in a spark-ignition internal combustion engine, which reduces the advance angle of ignition timing when knocking is detected by the knocking sensor, and a knocking sensor and a knocking suppressing liquid injected into the combustion chamber of the internal combustion engine. a knock suppressing liquid injection supply means for controlling the knock suppressing liquid, a flow control means for controlling the increase or decrease of the flow rate of the knock suppressing liquid injected into the combustion chamber, an ignition timing setting means for setting the ignition timing, and a knock suppressing liquid injection supply means for controlling the knock suppressing liquid by the knocking sensor. When this is detected, the knocking suppressing liquid injection supplying means is controlled to inject and supply knocking suppressing liquid to the combustion chamber in response to the detection, and even in such a case, knocking is detected by the knocking sensor. In some cases, in response to this, the flow rate control means is controlled to increase the amount of the knock suppressing liquid injected and supplied to the combustion chamber, so that the knock suppressing liquid is injected and supplied to the combustion chamber at the maximum supply amount. Nevertheless, non-king is detected by the knocking sensor and is sometimes achieved by a knocking suppression device for a spark ignition internal combustion engine having a control device that controls to reduce the advance angle of the ignition timing.

Effects and Effects of the Invention According to the present invention, when knocking is detected by the knocking sensor, the advance angle of the ignition timing is not reduced, but the knocking suppressing fluid is first injected and supplied to the combustion chamber, and then However, when knocking is detected by the knocking sensor, the amount of knocking suppressing fluid injected into the combustion chamber is increased, and even though the knocking suppressing fluid is being injected into the combustion chamber at the maximum amount, the knocking sensor detects knocking. When detected, the ignition timing advance angle is reduced. Therefore, compared to conventional methods and devices in which the advance angle of the ignition timing is immediately reduced when knocking occurs, it is possible to reduce the reduction in output of the internal combustion engine, and to respond in response to the occurrence of knocking. The amount of the knock suppressing fluid to be injected and supplied is adjusted accordingly, so that a predetermined amount of the knock suppressing fluid is injected and supplied in accordance with the operating conditions of the internal combustion engine, regardless of whether knocking is occurring or not. The amount of consumption of the knock suppressing liquid can be reduced compared to the case of the knock suppressing liquid, and thereby the capacity of the reservoir tank storing the knock suppressing liquid can be reduced.

According to one preferred embodiment of the method and device of the present invention, when the knocking suppressing liquid is being injected and supplied to the combustion chamber and no knocking is detected by the knocking sensor, the knocking suppressing liquid is injected and supplied to the combustion chamber. The advance angle of the ignition timing is increased when the knocking sensor does not detect knocking even if the liquid is corrected to be reduced and the knocking suppressing liquid is not injected and supplied to the combustion chamber. According to this embodiment, the consumption of the knock suppressing fluid is further reduced, and the internal combustion engine is operated with the ignition timing advanced to the limit just before knocking occurs, so that the output of the internal combustion engine is reduced. can be further improved.

EXAMPLES The present invention will now be described in detail by way of examples with reference to the accompanying drawings.

FIG. 1 is a schematic configuration diagram showing a spark ignition type internal combustion tEJI valve incorporating an embodiment of the non-knocking suppressor according to the present invention, and FIG. 2 shows the knocking suppressor according to the embodiment shown in FIG. 1. The block diagram, FIG. 3, is a flowchart showing one embodiment of the knocking suppression method according to the present invention, which is implemented by the embodiment shown in FIGS. 1 and 2.

In these figures, 1 indicates an internal combustion engine, and the internal combustion engine 1 has a cylinder block 2 and a cylinder head 3. The cylinder block 2 receives a piston 4 in a cylinder bore formed therein, and defines a combustion chamber 5 above the piston 4 in cooperation with the cylinder head 3.

An intake boat 6 and an exhaust boat 7 are formed in the cylinder head 3, and these boats are closed by an intake pulp 8 and an exhaust pulp 9, respectively. Further, an ignition plug 10 is attached to the cylinder head 3, and the ignition plug is supplied with the current generated by the ignition coil 11 via a distributor 12, and the current generated by the ignition coil 11 is supplied to the combustion chamber 3.
It is designed to generate sparks due to electrical discharge inside.

An intake manifold 13, a surge tank 14, a throttle valve 16 including a throttle valve 15, an intake pipe and an air cleaner (not shown in the figure) are connected in this order to the intake boat 6, and these constitute the intake system of the engine. .

A fuel injection valve 17 is attached near the connection end of the intake manifold 13 to the intake boat 6. The fuel injection valve 17 is connected to a fuel tank 22 storing a liquid fuel 21 such as gasoline through a fuel supply conduit 20 having a fuel pump 18 and a fuel filter 19 therebetween. A return conduit 23 is connected in communication between a portion of the fuel supply conduit 20 downstream of the fuel filter 19 and the fuel tank 22, and a portion of the fuel supply conduit 20 downstream of the fuel pump 18 is connected midway through the return conduit. A pressure control valve 24 is provided to control the fuel pressure within the portion wJ to a predetermined value. The fuel injection valve 17 is injected into the fuel pump 2 by the fuel pump 18.
2, fuel is supplied through a fuel supply conduit 20, and the valve opening time is controlled by a signal generated by a control device 25, which will be explained in detail later, and the amount of fuel injection is controlled by metering. ing.

One end of an S pipe 27 having an electromagnetic flow control valve 26 in the middle is connected to a part of the fuel supply pipe 20 downstream from the part to which the return pipe 23 is connected, and the other end of the pipe 27 is connected to an electromagnetic flow control valve 26. The switching valve 20 and the conduit 29 communicate with a reservoir tank 31 that stores alcohol 30 as a knock suppressing liquid. An alcohol pump 32 and an alcohol filter 33 are provided in the middle of the conduit 29. A return conduit 34 is connected between the switching valve 28 and the reservoir tank 31, and the switching valve 28 is connected to the control device 25. Based on a positive signal, the S pipe 29 and the conduit 27 are selectively switched to a first position where the S pipe 29 and the conduit 27 are connected to each other, and a second position where the two conduit pipes are connected to the return conduit 34. There is. The switching valve 28 also has a pressure control valve (not shown in the figure) inside that controls the pressure in the portion of the conduit 29 downstream of the alcohol pump 32 to a predetermined value.

The υj wave control device 25 may be a conventional microcomputer, an example of which is clearly shown in FIG. The microcomputer 25 includes a central processing unit (CPU, ) 3
5, read-only memory (ROM>36, random access memory (RAM>37), and input boat device 38
and an output port Bffff39, which are interconnected by a bidirectional common bus 40.

The input boat device 38 receives an intake pressure signal generated by an intake pressure sensor 42 attached to the surge pump 14, a cooling water temperature signal generated by a cooling water temperature sensor 43 attached to the cylinder block 2, and a cooling water temperature signal generated by a cooling water temperature sensor 43 attached to the cylinder block 2. A signal indicating that knocking has occurred generated by the knocking sensor 44, and a cylinder discrimination signal and a crank rotation angle signal generated by the cylinder discrimination sensor 45 and rotation angle sensor 46 attached to the distributor 12 are inputted, respectively. The data is converted into signals as appropriate and sent to the CPU.
35, the data is output to the CPU and RAM 37. Based on the data detected by the sensors according to the program and map stored in the ROM 36, the CPU 35 sets the fuel injection timing to υ1111, the ignition timing, and the alcohol injection amount to υ1111, and sends the fuel injection signal based thereon to the fuel injection valve 17. The ignition timing signal is output to the igniter 47, the switching signal to the switching valve 28, and the flow rate control signal to the flow rate control valve 26 via an output boat device 39 and a drive circuit (not shown). .

The igniter 47 is attached to the ignition coil 11 as shown in FIG.
When the ignition timing signal generated by 5 is given, the power supply circuit of the primary coil of the ignition coil 11 is cut off, and the advance angle of closing at the time of ignition is controlled (tII).

Next, referring to the flow "f yard" shown in FIG. 3, the operation of the embodiment shown in FIGS. 1 and 2 and one of the knock suppression methods according to the present invention carried out by the embodiment An example will be explained.

The routine shown in FIG. 3 is performed for each stroke of the internal combustion engine, and in the first step 1, the engine rotational speed N is determined based on the crank rotation angle measured by the rotation angle sensor 46. , the intake pressure P measured by the intake pressure sensor 42
Then, each data of the cooling water 1 t measured by the cooling water temperature sensor 43 is read. In the next step 2, I! Based on the data of engine speed N and noon intake pressure P, RAM3
The optimal ignition timing advance angle T from the map stored in 7.
o is squeezed out.

In the next step 3, the engine speed N is within a predetermined range,
For example, it is determined whether 800 rpm+≦N≦5600 rpm. If it is determined that the engine speed is within a predetermined range, then in the next step 4, the intake pressure P is determined to be equal to or higher than a predetermined value, for example, P≧−2001111.
! A determination is made as to whether or not it is equal to or higher than lHg. If it is determined that the intake pressure is greater than or equal to a predetermined value, in the next step 5, it is determined whether or not the cooling water temperature t is greater than or equal to a predetermined value. A determination is made.

If it is determined that the cooling water temperature is equal to or higher than the predetermined value, the process proceeds to the next step 6, where the switching valve 28 is switched to the first position or maintained at the first position, and then the heating step is performed. Proceed to step 7. If it is determined in step 3 that the engine speed is not within the predetermined range, and if it is determined in step 4 that the intake pressure is not greater than the predetermined value, then in step 5 If it is determined that the cooling water temperature is not higher than the predetermined value, the switching valve 28 is switched to the second position or maintained at the second position in the next step 8, and then reset. .

In step 7, it is determined whether or not knocking is occurring and whether or not a signal is being output from the knocking sensor 44. If it is determined that knocking has occurred, proceed to the next step 9,
Based on the signal output from the output boat device 39 to the flow control valve 26, it is determined whether the flow control valve is fully open, that is, whether the opening degree θ of the flow control valve is θnax. be exposed.

If it is determined that the flow m control valve 26 is not fully open, the process proceeds to the next step 10, where the opening degree θ of the flow m control valve is increased by a predetermined minute amount Δθ, and then reset. Further, if it is determined in step 9 that the opening 1 θ of the 8i quantity control well 26 is fully open, in the next step 11, the ignition timing advance angle T is adjusted by a predetermined minute difference ΔT. reduced and then reset.

If it is determined in step 7 that knocking has not occurred, the flow ffi is determined in the next step 12.
It is determined whether the ff1lJ all valve 2G is fully open, that is, whether or not the opening degree is θ-〇.

If it is determined that the flow control til+ valve is not fully open, the opening degree θ of the flow m control valve is reduced by a predetermined minimum Δθ in the next step 13, and then reset. On the other hand, if it is determined in step 12 that the flow m control valve is fully open, in the next step 14, it is determined whether the ignition advance angle T is T≦To−ΔT. A determination is made.

If it is determined that T≦To−ΔT, in the next step 15, the ignition vIJ! l] The lower advance angle is increased by ∆K and is then set accordingly.゛If it is determined in step 14 that T>To-Δ, the ignition timing advance angle T is changed to the advance angle extracted in step 2 in the next step 16. "To, and then reset."

Thus, according to the illustrated embodiment, when the occurrence of knocking is detected, the advance angle of the ignition timing is not first reduced, but the opening degree of the flow m control valve is increased by a predetermined amount, thereby reducing the amount of alcohol. If the injection supply amount is increased and non-king occurs even if the alcohol injection supply amount reaches the 100% value, the ignition timing advance angle is reduced by a predetermined amount, and if knocking no longer occurs, the flow m The opening degree of the control valve 26 is reduced by a predetermined amount, the amount of alcohol injection and supply is reduced by a predetermined amount, and if knocking does not occur even when the flow rate control valve is fully opened, the ignition timing advance angle T is increased by a predetermined amount, This improves the output of the tsuboseki.

Although the present invention has been described in detail with respect to specific embodiments above, the present invention is not limited to such embodiments, and it is understood that various embodiments are possible within the scope of the present invention. It will be clear to those skilled in the art. For example, alcohol may be injected into the intake air stream via an alcohol injection valve attached to a surge tank or the like.

[Brief explanation of drawings]

FIG. 1 is a schematic configuration diagram showing a spark ignition internal combustion engine incorporating an embodiment of the knocking suppression device according to the present invention;
FIG. 2 is a block diagram showing the embodiment shown in FIG. 1;
FIG. 3 is a flowchart showing one embodiment of the knocking suppression method of the present invention carried out by the embodiments shown in FIGS. 1 and 2. 1... Internal combustion engine, 2... Cylinder block, 3...
・Cylinder head, 4...Piston, 5...Combustion chamber, 6...Intake boat, 7...Exhaust boat, 8...
Inhalation pulp. 9...Exhaust valve, 10...Spark plug, 11...
・Ignition coil, 12...Distributor, 13・
...Intake manifold, 14...Surge tank, 15
... Throttle valve, 16... Throttle body, 17... Fuel injection valve, 18... Fuel pump, 19
...Fuel filter, 20...Fuel supply conduit, 21.
... Liquid fuel, 22 ... Fuel tank, 23 ... Return S pipe, 24 ... Pressure control valve, 25 ... Control device (microcomputer), 26 ... Flow m control valve, 2
7... Conduit, 28... Switching valve, 29... Conduit, 3
0...Alcohol, 31...Reservoir tank, 32
...Alcohol pump, 33...Alcohol filter, 34...Return conduit, 35...CPLJ, 3
6...ROM, 37...RAM, 38...input boat @P? , 39... Output boat Hfff, 40.
...Common bus, 42...Intake pressure sensor, 43...
Cooling water temperature sensor, 44...Knocking sensor, 45.
...Cylinder discrimination sensor, 46...Rotation angle sensor, 47.
...Igniter patent applicant Toyota Motor Corporation representative
Attorney Patent Attorney Masatake Akashi Figure 1

Claims (2)

[Claims] (1) detecting knocking by a knocking sensor; when knocking is detected by the knocking sensor, injecting and supplying knocking suppressing fluid to the combustion chamber of the internal combustion engine;
Even after that, when knocking is detected by the knocking sensor, the amount of the knocking suppressing fluid injected and supplied to the combustion chamber is increased and the knocking suppressing fluid is injected and supplied to the combustion chamber at the maximum amount. A method for suppressing knocking in a spark ignition internal combustion engine, which reduces the advance angle of ignition timing when knocking is detected by the knocking sensor. (2) a knocking sensor, a knocking suppressing liquid injection supply means for injecting and supplying a knocking suppressing liquid to a combustion chamber of an internal combustion engine, and a flow rate control means for increasing and decreasing the flow rate of the knocking suppressing liquid injected and supplied to the combustion chamber; ignition timing setting means for setting ignition timing, and when knocking is detected by the knocking sensor, controlling the knocking suppressing liquid injection supplying means to inject and supply knocking suppressing liquid to the combustion chamber in response to the detection of knocking, After that, when knocking is detected by the knocking sensor, the flow rate control means is controlled to increase the amount of the knocking suppressing fluid injected into the combustion chamber in response to the knocking, so that the knocking suppressing fluid reaches its maximum level. a spark ignition internal combustion engine, comprising: a control device that controls to reduce the advance angle of ignition timing when knocking is detected by the knocking sensor even though the fuel is injected into the combustion chamber at the supplied amount; Knock suppression device.