JPS6032958A - Fuel control device for electronic fuel injection system engine - Google Patents

Abstract

PURPOSE:To improve acceleration responsive property by providing an acceleration detecting means for detecting the acceleration of an engine, a means for applying acceleration increment pulses to a duel injection valve and a means for applying temporary pulses to the fuel injection valve. CONSTITUTION:When an acceleration detecting means A judges the acceleration condition of an engine, an acceleration increment pulse applying means B is operated to generate temporary acceleration increment pulses. Also, a first temporary pulse applying means D for receiving signals from an idle switch C generates first temporary pulses when a throttle valve begins to open. Further, a second temporary pulse applying means E generates second temporary pulses a predetermined time after the first temporary pulses are generated. These pulses are applied to a fuel injection valve F separately from the basic pulse. Thus, acceleration responsive property in start or acceleration can be improved.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to a fuel control device for an electronic fuel injection engine, and particularly to a fuel control device for increasing the amount of fuel injection during acceleration. It's true.

(Prior art) Generally, in an engine that uses a fuel 1'+1 injection valve to supply fuel 31, the engine's rotational speed, intake negative pressure, etc. are detected, and pulses are generated in accordance with these. The fuel injection valve is configured to apply a pulse signal of a certain width to the fuel injection valve, and to increase or decrease the fuel supply m depending on the operating state. However, according to this J: Una control, when the throttle valve is pressed when starting from an idling state or during normal acceleration, the m for rrj''i of the fuel injection valve corresponds to the increase in intake negative pressure. There is a tendency for there to be a shortage of 1J fuel, which causes a problem that the required acceleration performance cannot be achieved.

To solve this problem, we installed a secondary system (installed an idle switch that is linked to the throttle valve), and when the switch changes from ON to OFF, that is, when the throttle valve starts to hear, there is no signal from this switch. Based on the signal, a temporary pulse different from the pulse with a pulse width corresponding to the above-mentioned engine speed and intake negative pressure is applied to the fuel injection valve, and the amount of fuel supplied is increased accordingly. Acceleration 1 (i) performance is being improved.

Furthermore, as disclosed in Japanese Patent Publication NXT 49-47931, for example, engine acceleration is detected based on changes in intake negative pressure, and a temporary pulse is applied to the fuel injection valve during acceleration to increase the intake negative pressure. Attempts have been made to improve acceleration performance by injecting more ml of fuel than the amount corresponding to the number of minutes.

By the way, when detecting the acceleration state by capturing changes in the intake negative pressure, a die 17 flam type pressure response mechanism is generally used as the negative pressure sensor, but this type of sensor number, L throttle There is a tendency for the operation to be slow in response to changes in the intake negative pressure accompanying the opening movement of the valve. Further, it takes some time after the negative pressure sensor responds to a change in the intake negative pressure until the fuel injection valve injects the fuel 1. Therefore, the timing of increasing the amount of fuel necessary for acceleration is delayed, making the driver feel that the acceleration response is poor. In addition, the injection amount increase control based on such changes in intake negative pressure,
Even if the increase control based on the signal from the idle switch described above is used (If), the increase control based on the change in the intake negative pressure 01
1 is delayed, and a state of fuel shortage occurs after fuel increase control is performed based on the signal from the idle switch.
During this period, the engine speed may temporarily stall.

(Object of the Invention) The present invention is intended to address the above-mentioned problems in electronic fuel injection type engines. , eliminates the delay in fuel increase timing due to response delay of the acceleration detection means, etc., and enables J3 t when starting or accelerating
: The purpose is to improve acceleration response.

(Composition of light) The present invention is configured as follows to achieve the above object.

That is, as shown in FIG. 1, when the acceleration detecting means A determines the acceleration state of the engine based on the temporal change rate of the intake negative pressure, the acceleration increasing pulse applying means B operates to generate a temporary acceleration increasing pulse. let Further, the first temporary pulse applying means receives a signal from the idle switch C that detects the fully open state of the throttle valve, and generates the first temporary pulse when the throttle valve starts to hear the signal, and also generates a first temporary pulse when the throttle valve starts to hear the signal. The second @ time pulse application means E receiving the signal from the predetermined time 11! after the above-mentioned first temporary pulse is generated. A second temporary pulse is generated when l has elapsed. These pulses are applied to the fuel 111% fl = 1 valve, which injects fuel at 16U in response to the input pulse signal, separately from the basic pulses that are applied in synchronization with the rotation of the engine. It consists of two.

(Example) Hereinafter, the present invention will be explained based on embodiments shown in the drawings.

As shown in FIG. 2, the engine 1 has a plurality of combustion engines 2...
2, and the negative side thereof is provided with an intake pipe 4 which has branch passages 3...3 communicating with each combustion outlet 2...2, respectively. The intake pipe 4 has an enono cleaner 5 at its end.
However, throttle valves 6 are provided on the downstream side thereof, and injectors 7, .

Of course, these? l! il'! l The injection valves 7...7 are supplied with a pulse signal 8 output from the control unit 8.
1 is applied, and when the voltage is applied, the injection valves 7 . . . 7 inject fuel corresponding to the pulse width of the 11 pulses. Therefore, the J control unit 8 receives an idle signal 82 from an idle switch 9 which outputs an ON signal when the throttle valve 6 is fully closed in conjunction with the throttle valve 6, and an idle signal 82 from the intake pipe. 4] A crank angle sensor that detects the crank angle of the engine 1, such as an intake negative pressure signal S3 from an intake negative pressure sensor 10 installed on the downstream side of the torque valve 5.
The output timing and pulse width of the pulse signal $1 are determined based on these signals 82 to S4.

Next, the operation of the above embodiment will be explained.

The control unit 8 is controlled by a microcomputer and executes a background routine shown in FIG. 3 and an interrupt routine shown in FIG.

Figure 4 i! The routine including 11J starts execution when the crankshaft of the engine 1 reaches a predetermined crank angle (for example, 60 degrees before the top dead center of a specific cylinder) according to the crank angle signal Q S 4 from the crank angle hinge sensor 11. Steps P+, P based on the crank angle signal S4
Calculate the engine rotation speed in step 2, and step 3
Intake negative pressure is detected by the intake negative pressure signal S3 from the intake negative pressure sensor 10.Next, in step P4, as shown in FIG. The pulse width of the basic pulse x 1 corresponding to the engine speed and intake negative pressure at that time is read from a map in which the pulse width is set in advance, and the injection timing is waited for in step P5.

Then, when a predetermined injection timing (for example, the upper row of a specific cylinder) comes, step P6 is executed, and the basic pulse of the above pulse width x 1 is set as a pulse 4m S + for each fuel injection valve 7...7 to be applied. As a result, m of fuel J corresponding to the rotational speed of the engine 1 and the intake negative pressure is supplied from the fuel injection valves 7...7 to each of the branch passages 3...3 leading to the intake pipe 4.
'11 will be injected respectively. Here, the basic pulse x1 is outputted as an IC pulse in synchronization with the engine rotation as shown in FIG. 6(C). .

However, the above-mentioned interrupt routine shown in FIG.
When a predetermined time comes during the execution of the background routine t1 shown in the figure, the background routine is temporarily stopped and executed, and when the execution is finished, the execution of the background routine is resumed. . Next, this background routine will be explained.

First, this routine initializes various numerical values in step 01'C, and then sets the intake negative pressure sensor 10 in step Q2.
The intake negative pressure value indicated by the signal S3 from the controller is A-D converted.

Next, in step Q3, it is determined whether the idle signal @$2 of the idle switch 9 hl etc. has been switched from ON to OFF. , the signal S2 is switched from ON to OFF, step Q4 is executed, and the first temporary pulse x2 different from the basic pulse x1 is output as shown in FIG. 6(d). As a result, when the throttle valve 6 is opened during acceleration, each fuel injection valve 7...7 will perform increased injection at approximately the same time.Then, the control unit 1-8 executes step Q7. However, at this point, even though the throttle valve 6 is activated, the intake air input to the control unit 1-8 as shown in FIG. The negative pressure signal S3 does not indicate an increase in the intake negative pressure. Therefore, the acceleration increase pulse x4 is not generated in step Q8, and the fuel injection is not performed.

However, since the control unit 8 executes step Q3 to step Q5 in the next and subsequent V cycles, the step Q6 is completed, and the second temporary pulse x3 is output.

Therefore, the second increase injection is performed following the first increase injection when the idle signal S2 is switched.

Then, while this second temporary pulse increases the injection amount once or several times, the signal 83 from the intake negative pressure sensor 10 begins to respond to the increase in the intake negative pressure. If the upper bound rate exceeds a certain level, the control unit 8 executes step Q8 following step Q7, and performs the sixth step.
As shown in the figure ([), acceleration increase m pulses x 4 are output.

In this way, the first
The second temporary pulse x3 will be output between the output of the temporary pulse x2 and the output of the acceleration multiplication pulse x4 due to the change in intake negative pressure, and the fuel shortage during that time will be resolved. In addition, the idle switch 9 is the thrower 1.
~ ON when valve 6 is fully open /Jl
Since the control switches to R, O, and 1, the above injection amount increase control is performed not only when accelerating from an idle state, but also during normal driving (accelerating at 1 o'clock) when throttle valves 1 to 6 are at 1; will be held.

(Effects of the Invention) As described above, according to the present invention, acceleration of the engine is detected by changes in intake negative pressure, and the injection amount is increased during acceleration. In an injection type engine, a temporary increase pulse is applied to the fuel injector when the throttle valve starts listening and after a predetermined period of time has elapsed. This eliminates the poor acceleration response caused by the delay in injection amount increase control based on changes in the upper I intake negative pressure when starting or accelerating, and improves acceleration performance (m).

[Brief explanation of drawings]

Fig. 1 is an overall diagram of the present invention, Fig. 2 is a system diagram showing an embodiment of the invention, and Fig. 3.4 does not show the operation of the embodiment. - Fig. 5 is an explanatory diagram of a map used in this embodiment, and Fig. 6 is a time chart 1 to 1 showing the operation of this embodiment. Δ... Acceleration detection means B... Acceleration period pulse application means C... Idle switch D... First temporary pulse application means [... Second temporary pulse application means F... Fuel injection valve 1...1 engine, 5...thrower 1 to le valve, 7.
・・Fuel injection valve, 9・IZLE switch, 10・
...Negative intake pressure [Applicant: Toyo Kogyo Co., Ltd. Figure 5 Engine rotation → Figure 6 OFF (C1)

Claims (1)

[Claims] (1) A fuel injection valve that injects fuel according to an input pulse signal and detects engine acceleration based on changes in intake negative pressure.
an acceleration detecting means for detecting acceleration; and a signal receiving means from the acceleration detecting means.
an acceleration increase pulse applying means for applying an acceleration increase pulse to the injection valve during acceleration; an idle switch for detecting a fully open position of the throttle valve; a first temporary pulse applying means for applying a temporary pulse of Jll+ to the spout valve; and a second temporary pulse applying means for applying a second temporary pulse to the nozzle valve when a predetermined time has elapsed after application of the first temporary pulse. An electronic fuel injection type one-engine fuel control device comprising a pulse application means.