JPH076478B2 - Ignition timing control device for internal combustion engine - Google Patents

Description

The present invention relates to an ignition timing control device for an internal combustion engine.

A conventional ignition timing control device of this type is disclosed in
There is one as shown in Japanese Patent No. 59-126071.

In the conventional device of this type, generally, the ignition timing is set when the reference crank angle position signal is output, and the ignition control is performed when the ignition timing is reached.

<Problems to be Solved by the Invention> By the way, particularly in an internal combustion engine or the like equipped with an electronically controlled fuel injection device, fuel injection control is performed with good responsiveness in accordance with the engine operating state, and therefore the following problems occur. Was occurring.

That is, during the acceleration operation, the fuel injection amount is increased and corrected, so that the combustion pressure (the indicated mean effective pressure) responds to the change in the opening of the intake throttle valve with good responsiveness and rises sharply as shown in FIG.

However, since the weight of the vehicle is large and the inertia is large, distortion of the force due to poor followability to the increase in output of the engine is accumulated somewhere in the vehicle during acceleration of the vehicle, and it is released all at once after the end of acceleration. As a result, as shown in the drawing, a vehicle torsional vibration (a jerky vibration in the traveling direction and the backward direction of the vehicle, hereinafter referred to as vehicle vibration) is generated, and a rotational fluctuation of the engine is generated to deteriorate drivability and riding comfort.

In the above-mentioned conventional ignition timing control, the ignition timing is set corresponding to the detected engine operating state (engine speed, load, etc.) when the operating state is steady. In the case of acceleration as described above, when the engine rotation fluctuation occurs, the ignition timing is also advanced / retarded as shown in FIG. 8 according to the rotation fluctuation. The engine speed fluctuation and the vehicle vibration are also promoted because the control is performed in the direction of promoting the engine. Moreover, such a phenomenon also occurs during deceleration operation. In order to solve such a problem, the applicant of the present application detects a rotational fluctuation during transient operation to detect a state of occurrence of a surge (a longitudinal vibration) of a vehicle, and thereby advances or retards the ignition timing in a direction of suppressing the surge. We proposed a control method (see Japanese Utility Model Application No. 60-150837).

By the way, in this device, the detection of the surge is performed as follows. That is, for each signal output of the signal (REF signal) output from the crank angle sensor for each reference crank angle (for example, 180 ° in a 4-cylinder engine), the reciprocal of the period T from the previous signal output to the previous signal output The rotation speed N ₁ is calculated as a proportional value, and the difference ΔN (= ΔN ₁ −ΔN ₀ ) from the rotation speed N ₀ calculated at the time of the previous signal output is calculated in the same manner as the change amount ΔN of the rotation speed N, and the magnitude thereof is calculated. That is, it is determined that the surge level is the surge level, and the advance / retard angle correction of the ignition timing corresponding to the surge level is performed to suppress the surge.

However, in such a method, the surge level should be detected by the vibration acceleration, and therefore, the change amount of the engine speed is obtained as the change amount for each output of the reference crank angle signal, and is used as a substitute for the detection of the surge level. However, the surge level varies depending on the engine speed at the time of occurrence, and when the ignition timing advance / retard correction control is performed based on the detection result, the surge convergence is excellent only in a certain rotation range. It was found that in other rotation speed regions, the effect was poor or, on the contrary, too effective, good characteristics could not be obtained.

The present invention has been made by paying attention to such a conventional problem, and accurately detects the surge level of the vehicle during overwave operation, and corrects and controls the ignition timing based on the detection result to thereby vary the engine speed. An object of the present invention is to provide an ignition timing control device for an internal combustion engine that suppresses vehicle vibration and improves drivability and riding comfort.

<Means for Solving Problems> Therefore, according to the present invention, as shown in FIG. 1, reference crank angle signal output means for outputting a signal for each reference crank angle during engine rotation, and engine speed for each reference crank angle. An engine speed detecting means for detecting the engine speed, an engine speed change amount calculating means for calculating an engine speed change amount for each reference crank angle signal input based on a detection signal from the engine speed detecting means, and the engine speed Rotation speed change amount conversion means for converting the rotation speed change amount for each reference crank angle calculated by the change amount calculation means into rotation speed change amount per unit time, and acceleration / deceleration for detecting the acceleration / deceleration operation state of the engine An operation detecting means, a basic ignition timing setting means for setting a basic ignition timing corresponding to a steady operation state according to an engine operating state, and an acceleration / deceleration operation detected by the acceleration / deceleration operation detecting means. Ignition timing correction means for correcting the basic ignition timing set by the basic ignition timing setting means in such a direction as to suppress a change in the engine rotational speed, depending on the rotational speed change amount converted by the rotational speed change amount converting means. And an ignition signal output means for outputting an ignition signal to the ignition device at the ignition timing corrected by the ignition timing correction means.

<Operation> When a signal is output from the reference crank angle signal output means for each reference crank angle, the engine speed detection means detects the engine speed based on the generation cycle of the signal and the like. As a difference between the engine speed detected this time and the engine speed detected last time, the amount of change in the engine speed is calculated by the number-of-rotations change calculating means.

The rotation speed change amount conversion means converts the change amount of the engine speed for each reference Kunrank angle generation cycle calculated as described above into the change amount of the engine speed per unit time.

On the other hand, the basic ignition timing setting means sets the basic ignition timing based on the engine operating state.

Then, when the acceleration / deceleration operation detecting means detects the acceleration / deceleration state, the direction of suppressing the change in the engine speed based on the amount of change in the engine speed per unit time converted as described above. The basic ignition timing is corrected.

When the ignition timing corrected in this way is reached, the ignition signal output means outputs an ignition signal to the spark plug to perform ignition.

<Example> Below, the Example of this invention is described based on drawing.

In FIG. 2 showing the configuration of the embodiment, an air flow meter 3 for detecting an intake air flow rate and a throttle sensor 5 as an acceleration / deceleration detecting means for detecting an opening of an intake throttle valve 4 are provided in an intake passage 2 of an engine 1. , Are provided, and these detection signals are input to the control device 6. Further, the engine 1 is provided with a fuel injection valve 7 for each cylinder. These fuel injection valves 7
Is opened by an injection pulse signal corresponding to the fuel injection amount from the control device 6, and fuel is injected and supplied to the engine.

An ignition plug 8 is provided in each cylinder of the engine 1.
The high voltage generated in the ignition coil 9 is sequentially applied to the spark plugs 8 through the distributor 10, whereby spark ignition is performed to ignite and burn the air-fuel mixture. Here, the ignition coil 9 controls the generation timing of the high voltage via the power transistor 11 attached thereto. The ignition timing is controlled by controlling the ON / OFF timing of the power transistor 11 with an ignition signal from the control device 6.

The distributor 10 has a built-in photoelectric crank angle sensor 12. The crank angle sensor 12 includes a signal disk plate 14 that rotates integrally with the distributor shaft 13, and a detection unit 15. The signal disc plate 14 is formed with 360 position signal (1 ° signal) slits 16 and four reference crank rank angle signal (180 ° signal) slits 17 for four cylinders. One of the slits 17 for crank angle signal is also used for determining the # 1 cylinder. The detection unit 15 detects the slits 16 and 17, and outputs a position signal and a reference crank angle signal including a cylinder discrimination signal to the control device 6. As described above, the crank angle sensor 12 has a function of the reference crank angle signal output means.

18 is an auxiliary air passage 19 that bypasses the throttle valve 4.
Idle control valve for controlling idle speed, which is installed in
0 is the air cleaner.

Next, the operation will be described with reference to the flowchart of FIG.

FIG. 3 is executed every time the reference crank angle signal is input, and the engine speed and the amount of change for each input of the reference crank angle signal, and the value obtained by converting this into the amount of change per unit time are obtained.

First, in step (denoted as S in the figure, the same applies hereinafter) 1,
The engine speed N is detected by calculation as a value that is inversely proportional to the period (measured by a software timer) from the last input of the reference crank angle signal to the current input.

This function corresponds to the engine speed detecting means.

In step 2, the engine speed N ₀ detected last time is subtracted from the engine speed N detected this time in step 1,
Change Δ in engine speed N for each reference crank angle signal input
Calculate N _R.

This function corresponds to rotation speed change amount calculation means.

In step 3, this engine speed for the next calculation is
Set to N ₀ .

In step 4, the change amount ΔN _R for each reference crank angle obtained in step 2 is converted into the change amount ΔN _T per unit time by the following equation, for example.

However, N _U is a unit speed (for example, 3000 rpm). 1 / N _U may be set as a constant.

Besides this, It can be converted in the same manner by using the above.

Next, the acceleration / deceleration operation detection routine will be described with reference to FIG. This routine is executed every unit time (for example, 10 ms).

In step 11, the throttle valve opening α is input from the throttle sensor 5.

In step 12, the change amount Δα of the throttle valve opening α (difference between the current value and the previous value of α) is calculated.

In step 13, it is determined whether or not the acceleration operation is performed depending on whether or not Δα is larger than a predetermined positive value Δα ₀ , and if YES, the process proceeds to step 14.

In step 14, it is determined whether or not the acceleration determination in step 13 is the first time. If it is the first time, the process proceeds to step 15 and the timer TMAC
After resetting C to 0, the routine proceeds to step 16 to reset the acceleration flag FACC to 1.

After the second acceleration judgment, proceed from step 14 to step 17 to increment the timer TMACC and then to step 1
Go to step 8 and compare the value of TMACC with the set value T ₀ (for example, 1 second). If TMACC <T ₀ , go to step 19 and accelerate the flag FAC.
C is held at 1, but when TMACC ≧ T ₀ , the process proceeds to step 20 and FACC is reset to 0.

After setting the acceleration flag FACC in this way and when the acceleration operation is not determined in step 13, the process proceeds to step 21, and the intake air flow rate detected by the air flow meter 3 and the routine detected in FIG. 3 are detected. Based on the engine speed N and
A basic fuel injection amount T _P proportional to the cylinder intake air amount per unit time is calculated.

In step 22, various correction coefficients COEF are set based on the cooling water temperature, the throttle valve opening degree, etc., and the voltage correction amount T _S based on the battery voltage is set.

In step 23, the final fuel injection amount Ti is calculated by the following equation.

Ti = T _P · COEF + T _S An injection pulse signal having a pulse width corresponding to the fuel injection amount Ti calculated in this way is output to the fuel injection valve 7 at a timing synchronized with the engine rotation, and the fuel injection valve 7 is driven. Then, fuel injection is performed.

Next, the ignition timing control routine will be described with reference to FIG.

In step 31, the basic ignition timing ADV ₀ is set based on the detected engine speed N and the calculated basic injection amount T _P by searching the map stored in the ROM or the like.

This function corresponds to the basic ignition timing setting means.

In step 32, it is determined whether the acceleration flag FACC is 1 or 0. If it is 1, the process proceeds to step 33.

In step 33, the corrected advance value HADV is retrieved from the map based on the change amount ΔN per unit time. As shown in FIG. 6, the corrected advance value is set so that the ignition timing is retarded as the change amount ΔN increases in a region where the change amount ΔN is positive (a region where the rotational speed tends to increase). In a region where the variation amount ΔN is negative (a region where the rotation speed tends to decrease), the ignition timing is set to advance as the variation amount ΔN increases. The corrected advance value HADV may be set corresponding to the engine characteristics in the area surrounded by the broken line in FIG.

In step 34, the ignition timing ADV (= ADV ₀ + HADV) is calculated by adding the corrected advance value HADV to the basic ignition timing ADV ₀ .

When the acceleration flag FACC is determined to be 0 in step 32, the routine proceeds to step 35, where the ignition timing ADV is set to the basic ignition timing A.
Set as DV ₀ .

In this way, an ignition signal is output in another routine (not shown) according to the ignition timing set in step 34 or step 35, and when the ignition timing is reached, the power transistor
The power supply to 11 is cut off, the spark plug 8 is discharged at a high voltage, and ignition is performed.

As described above, when the ignition timing ADV ₀ is corrected based on the change amount ΔN, the corrected ignition timing is retarded more than usual when the engine rotation tends to increase as shown by the solid line in FIG. When is decreasing, the angle is advanced more than usual. As a result, fluctuations in the combustion pressure (indicated average effective pressure) during acceleration operation are suppressed as indicated by the dotted line in FIG. 7, so engine speed fluctuations and vehicle vibrations are also suppressed as shown in the figure.

Further, in the present invention, the rotational speed change amount is calculated for each reference crank angle input from the normal crank angle sensor, and is corrected to the change amount per unit time, so that the surging (rotational fluctuation) is large. The accurate time-synchronous measurement circuit (IOLS
Cost I can be reduced because I) is unnecessary.

The ignition timing is advanced due to fluctuations in the indicated mean effective pressure of the combustion chamber, vehicle vibration due to the acceleration pickup (G sensor), etc.
The retard control may be performed. Further, as shown by the dotted line in FIG. 7, the ignition timing may be first sharply raised or lowered and then corrected so as to gradually change. Furthermore, a correction similar to the integral control as shown by the one-point chain stopper may be performed.

Further, in the present embodiment, although the ignition timing correction is performed only during the acceleration operation, the engine rotation variation and the vehicle vibration can be suppressed by similarly performing the ignition timing correction in the direction of suppressing the rotation variation during the deceleration operation.

<Advantages of the Invention> As described above, the present invention has a configuration in which the ignition timing is advanced / retarded in the direction of suppressing the engine rotation fluctuation during the acceleration / deceleration operation. As a result, the ride quality can be suppressed, the drivability can be improved, and the riding comfort can be improved.

Also, because the configuration is such that the change in engine speed is read for each reference crank angle and is corrected to the change amount per unit time,
The time-synchronous measurement circuit is unnecessary and can be implemented at low cost.

[Brief description of drawings]

FIG. 1 is a block diagram showing the configuration of the present invention, FIG. 2 is a configuration diagram showing an embodiment of the present invention, FIGS. 3 to 5 are flowcharts showing various control routines of the same embodiment, and FIG. Is a map of the correction advance value used for the same control, FIG. 7 is a diagram for explaining the operation of the conventional example and the example, and FIG. 8 is an ignition timing characteristic diagram. 1 ... Engine, 5 ... Throttle sensor, 6 ... Control device, 8 ... Spark plug, 9 ... Ignition coil, 10 ... Distributor, 11 ... Power transistor, 12 ... Crank angle sensor

Claims (1)

[Claims] 1. A reference crank angle signal output means for outputting a signal for each reference crank angle during engine rotation, an engine speed detection means for detecting an engine speed for each reference crank angle, and the engine speed detection means. Based on the detection signal of the reference crank angle signal, a rotation speed change amount calculation means for calculating the change amount of the engine rotation speed for each input of the reference crank angle signal, and a rotation speed change amount for each reference crank angle calculated by the rotation speed change amount calculation means. The rotational speed change amount conversion means for converting the engine speed to the rotational speed change amount, the acceleration / deceleration operation detection means for detecting the acceleration / deceleration operation state of the engine, and the steady operation state corresponding to the engine operation state A basic ignition timing setting means for setting a basic ignition timing, and a rotation speed converted by the rotation speed change amount conversion means during acceleration / deceleration operation detected by the acceleration / deceleration operation detection means. The ignition timing correction means for correcting the basic ignition timing set by the basic ignition timing setting means in a direction of suppressing a change in the engine speed, and the ignition timing corrected by the ignition timing correction means. An ignition timing control device for an internal combustion engine, comprising: an ignition signal output means for outputting an ignition signal to the ignition device.