JPS59183038A - Electronic engine control apparatus - Google Patents

Abstract

PURPOSE:To enable to obtain smooth feeling in driving vehicle, by selecting the most appropriate control mode according to the operational conditions of an engine in making accelerating or decelerating correction to a basic injection quantity of fuel. CONSTITUTION:A control unit 4 furnishes a signal instructing a basic injection quantity of fuel to an injector 6 on the basis of the data relating to the quantity of intake air supplied to an engine 1 that is obtained from the output signal of an air-flow meter 3 and data relating to the engine speed that is obtained from a crank-angle sensor 5. Further, the injection quantity of fuel supplied to the engine 1 is controlled by applying a signal instructing a corrected injection quantity of fuel on the basis of data representing the conditions of acceleration and deceleration of the engine 1 that is obtained from the output signal of a throttle sensor 7 and data representing the temperature of the engine 1 that is obtained from the output signal of a water-temperature sensor 8. That is, the shock caused at the time of acceleration is moderated by setting a plurality of different conditions for making the accelerating correction and making the accelerating correction by way of a plurality of different modes.

Description

[Detailed Description of the Invention] [Field of Application of the Invention] The present invention relates to an electronic fuel injection control device for an internal combustion engine such as a gasoline engine, and particularly to an electronic fuel injection control device for an internal combustion engine such as a gasoline engine. The present invention relates to a device that can perform such operations.

[Prior art]

In fuel injection type engines, control of the fuel supply amount is divided into basic injection amount control and correction injection amount control.The former mainly controls the air-fuel ratio, and the latter mainly controls the engine operating characteristics. It is common practice to do so.

Therefore, in such a conventional control device, the corrected injection amount during engine acceleration is controlled by interrupt injection and additional injection according to four stages of acceleration levels and engine cooling water temperature.

For this reason, with conventional control devices, if normal acceleration correction is applied when the engine is accelerated from an idle state with a low rotation speed, the air-fuel ratio becomes too rich, causing a shock due to acceleration, and driving The disadvantage is that the feeling deteriorates.

In addition, such conventional control devices detect when the engine is in a state of deceleration based on changes in the throttle opening, and correct the amount of fuel supplied during deceleration. However, this has the disadvantage that exhaust gas tends to deteriorate due to the response delay that exists in the system, especially when the vehicle is decelerated from a high load state with a large amount of fuel injection.

[Purpose of the invention]

An object of the present invention is to provide an engine control device that eliminates the drawbacks of the prior art described above and that allows a smooth driving feeling to be obtained at all times without generating a shock even when the engine accelerates from a deceleration state. Of course,
i1. Ta. Another object of the present invention is to provide an engine control device that prevents deterioration of exhaust gas even when the engine is decelerated from a high load state.

[Summary of the invention]

In order to achieve this object, one aspect of the present invention is that the control mode when acceleration correction or deceleration correction is entered is switched to one of a plurality of modes depending on the operating state of the engine at that time,
It is characterized by the fact that the optimum control mode is always selected.

[Embodiments of the invention]

Embodiments of the electronic engine control device according to the present invention will be described below with reference to the drawings.

FIG. 1 shows an embodiment of an engine control device to which the present invention is applied. In the figure, %1 is the engine, 2 is the air cleaner, and 3
4 is a hot wire air flow meter, 4 is a control unit, 5 is a crank angle sensor, 6 is an injector, 7 is a throttle sensor, 8 is a cooling water sensor, and 9 is an intake manifold.

The control unit 4 supplies the injector 6 with a signal that provides a basic injection amount based on the intake air amount data of the engine 1 based on the signal from the air flow meter 3 and the rotation speed data of the engine 1 based on the signal from the crank angle sensor 5. Acceleration of the engine 1 based on the signal of the throttle sensor 7,
A signal giving a corrected injection amount is supplied to the injector 6 based on the data representing the deceleration state and the data representing the temperature of the engine 1 based on the signal from the water temperature sensor 8, so that the fuel injection amount to the engine 1 is always in the optimum state. control.

By the way, in such an engine control device, as mentioned above, when accelerating from a state where the rotational speed of the engine 1 is below the idling state, the acceleration correction for normal acceleration is applied as is. If applied, the air-fuel ratio will become too rich, causing shock during acceleration.

Therefore, in one embodiment of the present invention, the conditions for entering the acceleration correction are set to a plurality of different conditions, and the acceleration correction is performed in a plurality of modes.

FIG. 2 shows an example of how the throttle opening and engine speed change over time when accelerating from an idling state.

In this embodiment, among the multiple conditions that apply to the acceleration correction described above, it is determined that the acceleration is from a time when the engine is in a deceleration state, when a predetermined period of time has elapsed from the time point 1o when the idle switch was turned OFF. For time T8 and a predetermined engine speed Ns where the engine speed is equal to or higher than the idle speed, the time when engine acceleration is detected is set to 11 after the idle switch is turned off, and the engine speed at that time is n.
This is carried out on the condition that the following equation (1) holds when 1.

nl<Ns When it is detected that the engine has entered an acceleration state by the signals from the throttle sensor 7 and the crank angle sensor 5, the moxibustion condition of the above formula (1) is checked, and it is determined that the moxibustion condition of formula (1) is satisfied. When it was not, the normal acceleration arrest and delinquency were carried out,
When formula (1) is satisfied, Fi is made to perform less correction than normal acceleration correction.

Therefore, the operation according to the above embodiment is shown in a flowchart as shown in FIG.

In the embodiment shown in Fig. 3, normal acceleration correction is performed by interrupt injection and additional injection relative to the reference injection amount, and the additional injection amount is calculated in four stages determined by the throttle angle, engine temperature, etc. It is designed to be carried out according to the level. When the above formula (1) is satisfied, the interrupt injection is stopped and the additional injection amount is calculated based on the level one level below the Luher. ,
This prevents the air-fuel ratio from becoming too rich due to the cracking, thereby preventing acceleration shock from occurring.

Therefore, according to the embodiment shown in FIG. 3, no shock occurs in the engine under any acceleration operation, and smooth acceleration operation can always be provided.

Next, in such an engine control device, as described above, even when the engine is decelerated from a high load state, the air-fuel ratio remains rich and the exhaust gas condition deteriorates.

Therefore, an embodiment of the present invention that improves this point will be described below.

In one embodiment of the present invention shown in FIG. 1, the fuel injection amount is controlled by the width of the pulse supplied to the injector 6. Therefore, if the width of the pulse giving the basic injection amount is Tl, then T1 is determined as shown in the following equation.

kl = constant F: intake air amount N: engine speed and 1 A predetermined correction is made to the pulse T1 that provides this basic injection amount and is supplied to the engine engine 16 in order to obtain an unnecessary injection amount. ing.

Of these, the correction during deceleration is performed by detecting deceleration of the engine using a signal from a throttle sensor 7 that detects the opening position of the throttle. In other words, deceleration is detected by comparing the throttle opening obtained last time with the throttle opening obtained this time.

If it is detected that deceleration has finally started, proceed to the next step (3).
The pulse width TI for fuel injection is corrected according to the formula so that the pulse width Txt4-this T2 is supplied to the injector 6.

T2 Ni ni 2・TI ・・・・・・・・・・・・
(3) In this equation (3), k2 is a deceleration correction coefficient, which is a value of 1 or less.

By the way, in the deceleration correction as described above, the condition of the exhaust gas deteriorates when the vehicle is decelerated from a high load, as described above.

In other words, when the engine is operated under high load, the amount of intake air increases and the basic injection pulse width TI becomes thicker.

Therefore, when decelerating from this region, the amount of air decreases rapidly, but since a large amount of fuel is flowing inside the intake manifold 9, the air-fuel mixture becomes rich and the exhaust gas deteriorates. be.

Therefore, in this embodiment, a soft timer by the microcomputer of the control unit 40 is activated, and when the basic injection pulse width T1 is greater than or equal to a predetermined value, this soft timer (referred to as TMI) is set, and when the pulse width T1 is less than or equal to the predetermined value, a countdown is performed. to be done. When deceleration is detected by the signal from the throttle sensor 7, if the count 1 of the soft timer TMI is 0, it is processed as normal deceleration correction and the count value of the soft timer TMI is not 0. When such a situation occurs, the deceleration correction is performed by switching to a plurality of modes so as to process the deceleration correction from the high load area.

In this way, when decelerating from a high load area, control will be performed in a mode different from normal deceleration correction.
Deterioration of exhaust gas can be prevented.

FIG. 4 is a flowchart of this embodiment, and the deceleration correction when the soft timer TMI is 0 is performed by setting the correction coefficient k in equation (3) to 0.8.
is not OK, control is performed so that 2 becomes 0.5 in the correction coefficient, and when decelerating from a high load region, the injection pulse width T2 becomes narrower, preventing the mixture from becoming richer. Purification of exhaust gas will be maintained.

Next, FIG. 5 is a flowchart showing the operation of another embodiment of the present invention. In the embodiment of FIG. 3, in order to detect a high load, whether the basic injection pulse width T1 has reached a predetermined value or not In contrast, the embodiment shown in FIG. 4 uses an intake negative pressure switch, and detects a high load state by turning it on and off.

According to this embodiment, by utilizing the fact that the negative pressure in the intake eyebrow fold 9 becomes close to atmospheric pressure in a high load state, a high load state can be easily and reliably detected by turning the negative pressure switch ON-OFF. .

[Droplight effect]

As explained above, according to the present invention, the fuel injection amount correction operation during engine acceleration and deceleration is performed in one of a plurality of control modes depending on the operating state before engine acceleration and deceleration. Since the engine is switched to
It is possible to easily provide an engine control device that can provide fine control according to the operating state of the engine and that does not cause shock during acceleration or deterioration of exhaust gas during deceleration.

[Brief explanation of drawings]

Fig. 1 is an overall configuration diagram showing one embodiment of an electronic engine control device according to the present invention, Fig. 2 is a characteristic curve diagram regarding time changes in throttle opening and engine speed, and Fig. 3 is an embodiment of the present invention. FIG. 4 is a flowchart showing the operation of another embodiment. FIG. 5 is a flowchart showing the operation of another embodiment.
It is. 1...Engine, 2...Air cleaner, 3...Hot wire type air flow 1k total, 4...Control unit,
5... Crank angle sensor, 6... Injector, 7
...Slot #-(=7s, g...Cooling water temperature sensor, 9...Intake manfold. Agent: Patent attorney Akio Takahashi Soim

Claims (1)

[Claims] 1. In an engine control device that controls the amount of fuel supplied to the engine by controlling both a basic injection amount and a correction injection amount for this basic injection amount, the above-mentioned correction when the engine accelerates is provided. An electronic engine six-way control device characterized in that the control of the injection amount is controlled by switching between two modes: Ngl and a second mode. 2. /l? In claim 1, the above-mentioned
The conditions for entering control in one of the first and second modes are that the time when it is detected that the engine operating state has become accelerated is within a predetermined time from the idling state, and the engine rotational speed has reached the predetermined rotational speed. An electronic engine control device characterized in that the electronic engine control device is configured to be in a state where the engine is not reached. 3. In an engine control device that controls the amount of fuel supplied to the engine by controlling both a basic injection amount and a correction injection amount with respect to this basic injection amount, the correction injection amount is controlled during engine deceleration, An electronic engine control device characterized in that it is configured to switch between a plurality of modes depending on the load condition of the engine. 4. The electronic engine control device according to claim 3, wherein the electronic engine control device is configured to detect the load condition of the engine based on the basic injection amount. 5. The electronic engine control device according to claim 3, characterized in that the load condition of the engine is detected by engine intake negative pressure.