JP2884875B2 - Ignition timing control device for resuming fuel supply of internal combustion engine - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ignition timing control for resuming fuel supply in an internal combustion engine for stopping fuel supply at a predetermined deceleration and controlling ignition timing to be retarded.

[0002]

2. Description of the Related Art Conventionally, in an internal combustion engine equipped with an electronic fuel injection control device, at a predetermined operation time, for example, 1800 rpm
When the throttle valve is fully closed at m or more, fuel injection is stopped. After that, when the rotational speed becomes equal to or less than 1200 rpm, fuel injection is restarted.

[0003] However, if the fuel supply is stopped or restarted at once in all cylinders, a large change in torque causes discomfort due to a shock. Some cylinders are designed to be performed step by step.
20374). Further, in order to further reduce the torque shock, there has been proposed an apparatus in which the ignition timing at the time of resuming the fuel supply is controlled to be retarded in parallel with the fuel supply stop and restart control.

[0004]

However, in the ignition timing retardation control system parallel to the fuel supply stop / restart control as in the above-mentioned conventional example, even if the fuel supply is restarted stepwise, the fuel supply is started in the first stage. Only when the retard control is performed, and when the fuel supply to all the cylinders is restarted, the retard control is not performed, so that the shock cannot be sufficiently reduced.

The present invention has been made in view of such a conventional problem, and in accordance with the stepwise control of the fuel supply restart, the ignition timing is retarded in accordance with the number of cylinders in which the fuel supply is restarted. An object of the present invention is to provide an ignition timing control device for resuming fuel supply of an internal combustion engine, which solves the above-mentioned problem by performing the operation stepwise.

[0006]

Therefore, an ignition timing control apparatus for resuming fuel supply of an internal combustion engine according to the present invention is shown in FIG.
As shown, fuel supply stop and restart control means for stopping fuel supply in all cylinders at the time of a predetermined deceleration operation, and thereafter restarting fuel supply after resuming all cylinder fuel after performing stepwise by a plurality of divided cylinder groups. Delays the ignition timing in response to
In an internal combustion engine provided with an ignition timing control means for turning the fuel supply and an ignition timing retard control means for gradually returning the ignition timing at the time of restarting the fuel supply to the advanced side, the restart is started every time the fuel supply is restarted step by step. With the ignition timing at the beginning as the initial value
Ignition timing according to the number of cylinders supplied with fuel
Thus, the configuration is such that the retard control amount setting means for setting the ignition timing retard control amount is provided.

[0007]

With this configuration, every time the number of cylinders for which fuel supply is restarted increases, the retard control is performed with the retard control amount set stepwise according to the number of cylinders as an initial value. ,
The torque shock at the time of stopping and restarting the fuel supply is reduced as much as possible.

[0008]

Embodiments of the present invention will be described below with reference to the drawings. In FIG. 2 showing the configuration of one embodiment, an internal combustion engine 1
The air is sucked through the air cleaner 2, the intake duct 3, the throttle chamber 4 and the intake manifold 5.

The intake duct 3 is provided with an air flow meter 6 for detecting an intake air flow rate Q. The throttle chamber 4 is provided with a throttle valve 7 interlocked with an accelerator pedal (not shown) to control the intake air flow rate Q. The throttle valve 7 is provided with a throttle sensor 15 for detecting the opening TVO by a potentiometer.

The intake manifold 5 is provided with an electromagnetic fuel injection valve 8 for each cylinder, and injects fuel supplied from a fuel pump (not shown) and controlled to a predetermined pressure by a pressure regulator to the intake manifold 5. Supply. The control of the fuel injection amount is performed by a control unit 9 having a built-in microcomputer and an engine rotation speed calculated based on an intake air flow rate Q detected by an air flow meter 6 and a signal from a crank angle sensor 10 built in a distributor 13. From N, the basic fuel injection amount T
Calculates the _P, and the basic fuel injection quantity T _P a final fuel injection amount T _I is calculated by correcting, based on the coolant temperature and the like, a drive pulse having a pulse width corresponding to the fuel injection amount T _I By outputting the signal to the fuel injection valve 8 in synchronization with the engine rotation, a required amount of fuel is injected and supplied to the engine 1. And at the time of predetermined deceleration operation,
For example, during a deceleration operation in which the throttle valve 7 is fully closed when the engine speed is equal to or higher than the first set value N ₀ , fuel injection for two cylinders is stopped, and after a predetermined time has elapsed, fuel injection for all four cylinders is stopped. . From this state, the engine speed is reduced to the second set value N.
_When it becomes ₁ (<N ₀ ) or less, fuel injection for two cylinders is restarted, and after a lapse of a predetermined time, fuel injection for all four cylinders is restarted. The control for stopping and restarting the fuel injection by the control unit 9 corresponds to the fuel supply and restart control means.

Here, the detection of the engine rotational speed is calculated as the reciprocal of the generation cycle of the reference signal REF position (time since the previous generation of the reference signal REF). Further, each cylinder of the engine 1 is provided with an ignition plug 11, and a voltage generated by an ignition coil 12 is constantly applied to the ignition plug 11 via a distributor 13, thereby spark-igniting the air-fuel mixture. To ignite and burn. Here, in the ignition coil 12, the generation timing of the high voltage is controlled via an attached power transistor 12a. Therefore, the ignition timing (ignition advance value) ADVT is controlled by the power transistor.
The OFF timing of 12a is performed by controlling the ignition timing signal from the control unit 9.

Here, the fuel supply stop / restart control during the deceleration operation performed by the control unit 9 and the ignition timing retard control performed in parallel with this will be described with reference to the program shown in the flowchart of FIG. In step (denoted by S in the figure) 1, it is determined whether or not normal injection is being performed in which all cylinders are injected in a four-cylinder engine.

When it is determined that the fuel injection is the normal injection, this routine is terminated. When it is determined that the fuel injection is not the normal injection, the routine proceeds to step 2, in which the fuel supply is stopped during the predetermined deceleration operation, or It is determined whether the fuel supply is restarted. If it is determined in step 2 that the fuel supply is to be stopped, the process proceeds to step 3 and it is determined whether the fuel supply has been stopped for two cylinders or all four cylinders have been stopped.

When it is determined in step 3 that the fuel supply has been stopped for two cylinders, the routine proceeds to step 4, where the retard control amount of the ignition timing is set to FCADV1. If it is determined in step 3 that the fuel supply has been stopped for all four cylinders, the process proceeds to step 5, and the retard control amount is set to FCADV1.
Set to + FCADV2. If it is determined in step 2 that the fuel supply is to be restarted, the process proceeds to step 6, where it is determined whether the fuel supply has been restarted for two cylinders or for all four cylinders.

When it is determined in step 6 that the fuel supply has been restarted for two cylinders, the process proceeds to step 7 in which the current retard control amount FCADV1 + FCADV2 is set as an initial value, and only the value of FCADV2 is set to 0 within a predetermined time from this value. Is gradually reduced as follows. When it is determined in step 6 that all four cylinders have resumed the fuel supply, the process proceeds to step 8, in which the current retard control amount FCADV1 is gradually reduced so as to become 0 within a predetermined time. In this way, in step 6, the initial value FCA of the retard control amount according to the restart of fuel supply for two cylinders
The function of setting DV1 + FCADV2 and setting the initial value FCADV1 in step 8 in response to the restart of fuel supply to all cylinders corresponds to the retard control amount setting means.

With such a configuration, as shown in FIG. 4, every time the fuel supply is restarted stepwise, the retard control amount is controlled in accordance with the number of cylinders. Can be mitigated as much as possible. In this embodiment, the ignition timing is controlled to be retarded from the time when the fuel supply is stopped. However, the retard control may be performed simultaneously with or immediately before the fuel supply is restarted.

[0017]

As described above, according to the present invention, since the retard control amount of the ignition timing is controlled stepwise in accordance with the number of cylinders restarted when fuel supply is restarted, the fuel supply is restarted. The torque shock can be reduced as much as possible.

[Brief description of the drawings]

FIG. 1 is a block diagram showing the configuration of the present invention.

FIG. 2 is a diagram showing a configuration of an embodiment of the present invention.

FIG. 3 is a flowchart showing an ignition timing control routine at the time of fuel supply stop and restart control according to the embodiment;

FIG. 4 is a time chart at the time of fuel supply stop and restart control of the embodiment.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Internal combustion engine 8 Fuel injection valve 9 Control unit 11 Spark plug

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int. Cl. ⁶ , DB name) F02D 43/00 F02D 41/10 F02D 17/02 F02P 5/15

Claims (1)

(57) [Claims] 1. A fuel supply stop / restart control means for stopping fuel supply in all cylinders during a predetermined deceleration operation, resuming fuel supply in a stepwise manner for each of a plurality of cylinder groups, and then resuming fuel in all cylinders. And the ignition timing is delayed according to the fuel supply stop.
In an internal combustion engine provided with an ignition timing control means for turning the fuel supply and an ignition timing retard control means for gradually returning the ignition timing at the time of restarting the fuel supply to the advanced side, the restart is started every time the fuel supply is restarted step by step. With the ignition timing at the beginning as the initial value
Ignition timing according to the number of cylinders supplied with fuel
An ignition timing control device for resuming fuel supply of an internal combustion engine, comprising a retard control amount setting means for setting an ignition timing retard control amount as described above .