JPH0751929B2 - Ignition timing control device for internal combustion engine - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ignition timing control device for an internal combustion engine for an automobile, and more particularly to an ignition timing control device for suppressing shock during acceleration.

<Prior Art> In recent years, internal combustion engines for automobiles, particularly those equipped with an electronically controlled fuel injection device, provide fuel with a high response in accordance with the engine operating state, so that the engine is not operated during acceleration operation. The torque follows the change in the opening of the throttle valve with good responsiveness and rises sharply. Therefore, an acceleration shock occurs.

Further, since the vehicle has a large weight and a large inertia, it is not possible to follow the sudden output increase of the engine with good responsiveness. Therefore, when the vehicle shifts from the acceleration state to the steady state, the vehicle reciprocates (changes in the vehicle front-rear G). ), Jerky vibrations occur, and engine rotation fluctuations occur, which deteriorates drivability and riding comfort.

Therefore, when acceleration is detected based on the amount of change in the throttle valve opening, the ignition timing is corrected to a retarded side by a predetermined amount to suppress a rapid torque change, and the ignition timing is changed to the engine rotation for a predetermined time thereafter. It is proposed to correct the engine speed based on the amount of change in the number of rotations (that is, advance when the rotation is falling and retard when the rotation is increasing) to suppress the rotation fluctuation. (See Japanese Patent Application No. 62-70439).

<Problems to be Solved by the Invention> However, recent demands for drivability for vehicles are extremely strict, and there is a demand for a feeling of acceleration that is contrary to the reduction of acceleration shock. Has become.

From this point, looking at the ignition timing control at the time of acceleration as a measure against acceleration shock, acceleration is detected based on the amount of change in the throttle valve opening, and only this acceleration detection is a condition, regardless of the gear position of the transmission. Since the condition is satisfied, even when the acceleration shock is not so problematic, the ignition timing control at the time of acceleration is performed, and there is a problem that the acceleration is greatly impaired depending on the gear position.

That is, in general, there is almost no problem about the acceleration shock at the first gear position in the market needs, and rather, the feeling of acceleration due to some shock is preferred. Further, since the driving force by the engine decreases at the high speed side gear position such as the fourth and fifth speeds, if the ignition timing control at the time of acceleration is performed at this gear position, the feeling of acceleration is significantly reduced.

In view of such problems, an object of the present invention is to make it possible to more favorably perform the ignition timing control for acceleration as a countermeasure against acceleration shock in consideration of the gear position of the transmission during acceleration. To do.

<Means for Solving Problems> Therefore, according to the present invention, as shown in FIG. 1, an engine operating state detecting means for detecting an engine operating state including an engine speed, a load, and a throttle valve opening, Basic ignition timing setting means for setting ignition timing based on the engine operating state detected by the engine operating state detecting means, and acceleration start based on the amount of change in throttle valve opening detected by the engine operating state detecting means An acceleration determination means for detecting the time, a time counting means for measuring an elapsed time from the time when the acceleration start is detected by the acceleration determination means, and the basic ignition timing until the first predetermined time elapses from the acceleration start based on the time counting means. A first ignition timing acceleration correction means for correcting the ignition timing set by the setting means to a retard side, and a second predetermined time after a lapse of the first predetermined time based on the timing means. A second ignition timing acceleration correction means for correcting the ignition timing set by the basic ignition timing setting means in a direction to suppress fluctuations in the engine speed detected by the engine operating state detection means, and A gear position detecting means for detecting a gear position, and the first and second gear positions when the gear position detected by the gear position detecting means at the time of detecting the start of acceleration by the acceleration determining means is a first speed gear or a high speed side gear position. The ignition timing control device for coping with the acceleration shock is configured by providing a small correction amount of the ignition timing acceleration correction means or an acceleration correction stop means for stopping the correction.

<Operation> When the acceleration determination means detects the start of acceleration based on the amount of change in the throttle valve opening, the first time until the first predetermined time elapses from the start of acceleration under the control of the time measuring means.
The ignition timing acceleration correcting means corrects the ignition timing to the retard side, whereby the increase in torque becomes relatively gentle and acceleration shock is prevented. After the lapse of the first predetermined time period, the second ignition timing acceleration correction means rotates the engine toward the advance side in response to the fluctuation of the engine speed, that is, when the engine speed is lowered, until the second predetermined time period elapses. When rising, the ignition timing is corrected to the retard side, whereby rotation fluctuation is prevented.

However, during the ignition timing control for acceleration, the gear position detected by the gear position detection means is determined, and in the case of the first speed gear or the high speed side (for example, fourth and fifth speed) gear position, the acceleration correction stop means The correction amount by the first and second ignition timing acceleration correction means is reduced or the correction is stopped. As a result, a sufficient feeling of acceleration can be obtained when accelerating at those gear positions where acceleration shock is hardly a problem, and of course, acceleration performance is also improved.

<Examples> Examples of the present invention will be described below.

Referring to FIG. 2, air is taken into the engine 1 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 a hot-wire type air flow meter 6 to detect the intake air flow rate. The throttle chamber 4 is provided with a throttle valve 7 that works in conjunction with an accelerator pedal (not shown) to control the intake air flow rate. The throttle valve 7 is provided with a potentiometer-type throttle sensor 8 for detecting the throttle valve opening, and the throttle sensor 8 has a built-in idle switch (not shown) that is turned on at the fully closed position of the throttle valve 7. ing. The intake manifold 5 is provided with an electromagnetic fuel injection valve 9 for each cylinder, and injects fuel controlled to a predetermined pressure by a pressure regulator fed from a fuel pump (not shown) to the engine 1.

The control of the fuel injection amount is calculated based on the intake air flow rate Q detected by the air flow meter 6 in the microcomputer incorporated in the control unit 20 and the signal from the crank angle sensor 10 incorporated in the distributor 13 described later. The basic fuel injection amount Tp = K · Q / N (K is a constant) is calculated from the engine speed N to be stored, and the final fuel injection amount Ti = Tp · COEF + Ts (COEF
Is a correction coefficient including an acceleration correction coefficient and Ts is a voltage correction amount), and a drive pulse signal having a pulse width corresponding to Ti is given to the fuel injection valve 9 at a predetermined timing synchronized with the engine rotation.

Each cylinder of the engine 1 is provided with a spark plug 11, to which a high voltage generated in an ignition coil 12 is sequentially applied via a distributor 13, whereby spark ignition is performed to ignite and burn an air-fuel mixture. . Here, the ignition coil 12 has its high voltage generation timing controlled via a power transistor 12a attached thereto. Therefore, the ignition timing is controlled by controlling the on / off timing of the power transistor 12a with the ignition signal from the control unit 20.

For this ignition timing control, the engine speed N calculated based on the signal from the crank angle sensor 10 as a parameter of the engine operating state, and the basic fuel injection amount calculated as described above to represent the load Tp and are used. Further, the throttle valve opening TVO detected based on the signal from the throttle sensor 8 is used. Further, a signal from the gear position sensor 15 that detects the gear position of the transmission 14 is used.

Here, the crank angle sensor 10, the air flow meter 6 and the throttle sensor 8 correspond to engine operating state detecting means,
The gear position sensor 15 corresponds to gear position detecting means, and the ignition coil 12, the distributor 13 and the spark plug 11 constitute an ignition device.

The microcomputer in the control unit 20 performs arithmetic processing according to the ignition timing control routine shown as a flowchart in FIGS. 3 and 4 to control the ignition timing (ignition advance angle) ADV.

The ignition timing control routine of FIG. 3 is executed every predetermined time. As a premise of this routine, although omitted in the flowchart, the throttle valve opening TVO
_Is detected, the previous value is stored as TVO _oLd , and then the current value
Stored as TVO _new and the amount of change in throttle valve opening Δ
TVO = TVO _new −TVO _oLd is calculated. Further, the engine speed N is detected, the previous value is stored as N _oLd , the current value is stored as N _new , and the engine speed change amount ΔN =
N _new −N _oLd is calculated.

In step 1 (denoted as S1 in the figure; the same applies hereinafter), the value of the acceleration determination flag F ₁ is determined. If F ₁ = 0 (before acceleration determination), the process proceeds to step 2 and the throttle valve opening degree Acceleration determination is made as to whether or not the change amount ΔTVO is equal to or greater than a predetermined value. The step 2 corresponds to the acceleration determining means.

If ΔTVO <predetermined value and acceleration is not determined,
From step 2 to step 4, the acceleration correction amount DLTADV is set to zero.

Then, the routine proceeds to step 20, where the basic ignition timing MADV is set by searching with reference to the map based on the engine speed N and the basic fuel injection amount Tp. This step 20 corresponds to the basic ignition timing setting means.

Then, the routine proceeds to step 21, where the acceleration correction amount DLTADV (DLTADV = 0 in this case) is added to the basic ignition timing MADV to calculate the final ignition timing ADV, and this routine is ended.

If ΔTVO ≧ predetermined value and acceleration start is detected, the process proceeds from step 2 to step 3 and the gear position sensor
Determine the gear position based on the signal from 15.

In the case of the 1st, 4th, or 5th gear position, the process proceeds from step 3 to step 4, and the acceleration correction amount DLTADV is set to zero. Then, as in the case described above, the routine proceeds to steps 20 and 21, where the ignition timing ADV is set without acceleration correction, and this routine ends. Therefore, in this case, the acceleration determination flag F ₁ is maintained at 0, and the ignition timing control for acceleration as a countermeasure against acceleration shock is not entered. Therefore, step 3 corresponds to the acceleration correction stopping means.

In the case of the 2nd speed or the 3rd speed gear position, the control proceeds to the ignition timing control for acceleration as a countermeasure against acceleration shock. That is, the routine proceeds from step 3 to step 5 to set the acceleration determination flag F ₁ to 1, and then proceeds to step 6 to start the timer TIM as a time measuring means.

Then, the routine proceeds to step 7, where the retard amount TRADV (negative value) is set by searching according to the acceleration level by referring to the map based on the variation amount ΔTVO of the throttle valve opening at the time of acceleration determination. Further, the process proceeds to step 8 to set the time coefficient KDADV to 1 and the phase control amount DNADV to 0.

Then, the routine proceeds to step 17, where the acceleration correction amount DLTADV is calculated according to the following equation.

DLTADV = TRADV · KDADV + DNADV In this case, since KDADV = 1 and DNADV = 0, DLTADV = TRADV.

Then, proceed to steps 20 and 21 to set the ignition timing ADV,
This routine ends. Therefore, the ignition timing in this case
ADV is the basic ignition timing MADV corrected to the retard side by TRADV.

When this routine is executed after the acceleration determination (that is, after the acceleration determination flag F ₁ becomes 1), the process proceeds to step 9 by the determination of the value of the acceleration determination flag F _{1 in} step 1.

Step comparison 9 the value of the timer TIM and a first predetermined time T _1, and it is to the step 17,20,21 If TIM <T ₁ (i.e. first predetermined time T ₁ from the start of acceleration) move on.

Therefore, the ignition timing is corrected to the retard side by TRADV until the first predetermined time T ₁ has elapsed from the start of acceleration. Therefore, the steps 7, 8, 9, 17, 20, 21 correspond to the first ignition timing acceleration correction means.

When the first predetermined time T ₁ has elapsed from the start of acceleration, the process proceeds from step 9 to step 10 to compare the value of the timer TIM with the second predetermined time T _2, and TIM <T ₂ (that is, from the start of acceleration to the first If the second predetermined time T _{2 has} elapsed after the predetermined time T _{1 has} passed, the process proceeds to step 11. In step 11, the time coefficient KDADV is 0
If it is not 0, the time coefficient KDADV (initial value 1) is decreased by a predetermined amount in step 12.

Then, the procedure proceeds to step 13, where the value of the phase control start flag F ₂ is determined, and if F ₂ = (before phase control start), then step
Proceeding to 14, it is judged whether or not the change amount ΔN of the engine speed becomes negative (that is, the engine speed starts to decrease), and ΔN
If ≧ 0, proceed to steps 17, 20, and 21.

Therefore, after the elapse of the first predetermined time T ₁ , the acceleration correction amount DLTADV = TRADV · KDADV (however, KD
ADV: 1 → 0), and the ignition timing ADV gradually approaches the basic ignition timing MADV.

If ΔN <0 in the determination in step 14, the process proceeds to step 15 to set the phase control start flag F ₂ to 1 and then proceeds to step 16 to start the phase control.

Further, when the phase control start flag F ₂ is set to 1, the process proceeds to step 16 from the next time based on the determination of the value of the phase control start flag F ₂ in step 13, and the phase control is performed.

The control contents of the phase control are shown in FIG.
The positive / negative of ΔN is judged with, and if ΔN <0 (rotational drop), the process proceeds to step 32, and it is determined whether or not the time coefficient KDADV is 0. = K2X · (−ΔN), and if it has already become 0, proceed to step 34, and the phase control amount DNADV = K2Y · (−
ΔN). K2X and K2Y are constants. Also, step 3
If ΔN ≧ 0 (rotation increase) in the judgment in 1, step 3
After setting the time coefficient KDADV to 0 in step 5, the process proceeds to step 36 to set the phase control amount DNADV = −K1 · ΔN. K1 is a constant.

Therefore, the phase control amount DNADV has a positive value for correction to the advance side when the rotation falls, and the phase control amount DNADV has a negative value for correction to the retard side when the rotation increases.

When the phase control amount DNADV is set in this way, the routine proceeds to step 17, where the acceleration correction amount DLTADV is set based on this, and the routine proceeds to steps 20 and 21 where the ignition timing ADV is set.
Is calculated.

Thus, until the second predetermined time elapses, the ignition timing is corrected to the advance side when the rotation is decreased, and the ignition timing is corrected to the retard side when the rotation is increased to suppress the rotation fluctuation. Therefore, the steps 9, 10, 16, 17, 20, and 21 correspond to the second ignition timing acceleration correction means.

When the second predetermined time T ₂ has elapsed from the start of acceleration, the step
After proceeding from step 10 to step 18, both the acceleration determination flag F ₁ and the phase control start flag F ₂ are set to 0, then proceeding to step 19, the acceleration correction amount DLTADV is set to 0, and proceeding to steps 20 and 21, ignition timing ADV Determine. This returns to normal control.

FIG. 5 shows the state of the ignition timing control at the time of acceleration.

In the above embodiment, the acceleration correction is stopped at the time of accelerating at the 1st, 4th, and 5th gear positions, but the acceleration correction amount may be decreased as compared with the acceleration at the 2nd, 3rd speed gear position. Also, 1
The acceleration correction may be stopped at the time of acceleration at the high speed gear position, and the acceleration correction amount may be decreased at the time of acceleration at the fourth and fifth speed gear positions. To decrease the acceleration correction amount, use TRADV, K2X, K2Y,
The value of K1 should be reduced.

<Effects of the Invention> As described above, according to the present invention, acceleration timing ignition timing control for acceleration shock countermeasures is performed at the time of acceleration at an intermediate gear position, and acceleration is performed at acceleration at the first speed or high speed side gear position. Since the hour ignition timing control is stopped or the correction amount is made small, there is an effect that both reduction of the acceleration shock and improvement of the feeling of acceleration can be achieved in consideration of the gear position during acceleration.

[Brief description of drawings]

FIG. 1 is a block diagram showing the configuration of the present invention, FIG. 2 is a system diagram showing an embodiment of the present invention, FIGS. 3 and 4 are flow charts showing control contents, and FIG. 5 shows control characteristics. It is a time chart. 1 ... Engine, 6 ... Air flow meter, 7 ... Throttle valve, 8 ... Throttle sensor, 9 ... Fuel injection valve, 10
…… Crank angle sensor, 11 …… Spark plug, 12 …… Ignition coil, 13 …… Distributor, 14 …… Transmission, 15 …… Gear position sensor, 20 …… Control unit

Claims (1)

[Claims] 1. An engine operating state detecting means for detecting an engine operating state including an engine speed, a load and a throttle valve opening,
Basic ignition timing setting means for setting ignition timing based on the engine operating state detected by the engine operating state detecting means, and acceleration start based on the amount of change in throttle valve opening detected by the engine operating state detecting means An acceleration determination means for detecting the time, a time counting means for measuring an elapsed time from the time when the acceleration start is detected by the acceleration determination means, and the basic ignition timing until the first predetermined time elapses from the acceleration start based on the time counting means. First ignition timing acceleration correction means for correcting the ignition timing set by the setting means to the retard side, and the basic means for the second predetermined time after the first predetermined time elapses based on the timing means. A second ignition timing acceleration for correcting the ignition timing set by the ignition timing setting means in a direction to suppress the fluctuation of the engine speed detected by the engine operating state detecting means. Positive means, gear position detecting means for detecting the gear position of the transmission, and when the gear position detected by the gear position detecting means when the acceleration start is detected by the acceleration determining means is the first speed gear or the high speed side gear position. An ignition timing control device for an internal combustion engine, comprising: an acceleration correction stop means for reducing a correction amount by the first and second ignition timing acceleration correction means or for stopping the correction.