JPH0636301Y2 - Ignition timing control device for internal combustion engine - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial field of application> The present invention relates to an ignition timing control device for an internal combustion engine, and more particularly to improvement of retard correction control for mitigating acceleration shock.

<Prior Art> A conventional ignition timing control device is disclosed in, for example, JP-A-59-12.
There is one such as shown in Japanese Patent No. 6071.

In the conventional type of this type, generally, when the reference crank angle position is detected, the ignition timing corresponding to the operating state is calculated from the ignition timing data set in advance according to the operating state such as the engine load and the rotation speed. Data is searched for, the ignition timing is measured from the reference crank angle position, and an ignition signal is output to the ignition device when the ignition timing is reached.

By the way, in an internal combustion engine equipped with an electronically controlled fuel injection device, in particular, the fuel injection control is performed with good responsiveness according to the operating state of the engine, and thus has the following problems.

That is, during acceleration operation, the fuel injection amount increases in proportion to the engine demand, the engine torque follows the change in the opening of the throttle valve with good responsiveness, and rises sharply. However, since the vehicle has a large weight and a large inertia, the vehicle speed and the engine speed cannot follow the rapid output increase of the engine with good responsiveness.
Torsional vibration of the vehicle is generated and the engine rotation is also changed, which deteriorates the riding comfort.

As a countermeasure against such vehicle vibration, conventionally, as disclosed in Japanese Unexamined Patent Publication No. 61-283748, there is a technique that retards the ignition timing immediately after acceleration to suppress the rise of engine torque.

<Problems to be Solved by the Invention> However, in the system that suppresses the rise of the engine torque by the retard control of the ignition timing, the change of the air amount is small with respect to the change of the throttle valve opening. Even in acceleration in the flat region), the same retardation control as that during normal acceleration in which the air amount changes greatly is performed. Therefore, during acceleration in the Q flat region, hesitation (breathing) may occur due to a decrease in combustion pressure. It was

That is, in the acceleration in the Q flat region, since the rise of the engine torque with respect to the change of the throttle valve opening is slow and the acceleration shock is slight, it is not necessary to retard the ignition timing to suppress the engine torque. However, since the Q flat region was not discriminated in the retard correction condition, the ignition timing retard correction was performed in the same manner as in normal acceleration, and hesitation may occur.

The present invention has been made in view of the above problems, and prohibits retard control in acceleration in the Q flat region that does not require retard control of ignition timing, thereby causing hesitation during acceleration in the Q flat region. This is intended to prevent this and improve acceleration drivability.

<Means for Solving Problems> Therefore, in the present invention, as shown in FIG. 1, a throttle valve opening degree detecting means for detecting an opening degree of a throttle valve provided in an intake passage of an internal combustion engine, and Acceleration operation detection means for detecting acceleration operation of the engine based on the rate of change of throttle valve opening detected by the throttle valve opening detection means, and engine operation state detection means for detecting engine operation state including at least engine rotation speed And a basic ignition timing setting means for setting a basic ignition timing corresponding to a steady operating state according to an engine operating state, and a predetermined period after the acceleration operation is detected at least on condition of acceleration detection by the acceleration operation detecting means. Acceleration retard correction means for correcting the basic ignition timing set by the ignition timing setting means according to the acceleration state, the basic ignition timing setting means, and the acceleration delay angle Ignition signal output means for outputting an ignition signal to the ignition device at the ignition timing set or retarded by the correction means, and retard angle correction for setting a throttle valve opening region for prohibiting the retard angle correction in accordance with the engine speed. The throttle valve opening detected by the throttle valve opening detection means at the first time of the acceleration operation detection by the prohibition area setting means and the acceleration operation detection means is the throttle valve opening set by the retard correction inhibition area setting means. When included in the region, the ignition timing control device is configured to include retard correction inhibiting means for inhibiting retard correction of the ignition timing by the acceleration retard correction means.

<Operation> According to the ignition timing control device having such a configuration, the retardation correction prohibition region setting means sets the throttle valve opening region in which the retardation correction is prohibited in accordance with the engine speed, and the throttle valve opening region is set in this throttle valve opening region. When the throttle valve opening at the first time of acceleration detection is included, the retard correction of the ignition timing by the acceleration retard correction means is prohibited by the retard correction prohibiting means.

That is, the operating region (Q flat region) in which the change in the intake air flow rate is small with respect to the change in the opening of the throttle valve changes according to the engine rotation speed, and the higher the engine rotation speed, the higher the opening. Therefore, in order to prohibit the retard correction of the ignition timing in the Q flat region, the throttle valve opening region in which the retard correction is prohibited is set according to the detected engine rotation speed, and the acceleration is from the Q flat region. When it is determined that the ignition timing retard correction for suppressing the rise of the engine torque is prohibited, the normal ignition timing control is performed.

<Example> An example of the present invention will be described below.

In FIG. 2, the engine 1 has an air cleaner 2 and an intake duct.
3, Air is taken in through the throttle chamber 4 and the intake manifold 5. An air flow meter 6 for outputting a voltage signal corresponding to the intake air amount Q to the intake duct 3
And a throttle valve 7 is provided in the throttle chamber 4 and the opening degree of the throttle valve 7 is variably operated by an accelerator pedal (not shown).
The intake air flow rate is controlled. Reference numeral 8 denotes a throttle sensor as a throttle valve opening detecting means for detecting the opening of the throttle valve 7.

Further, the intake manifold 5 is equipped with a fuel injection valve 9 for each cylinder, and the valve is opened by a drive pulse signal output from a control unit 22 having a built-in microcomputer to control the fuel injection amount to each cylinder. Control.

On the other hand, the spark plug 10 installed in each cylinder of the engine 1
The high voltage generated in the ignition coil 11 is sequentially applied through the distributor 12, and the spark ignition by the high voltage is used to ignite and burn the air-fuel mixture in the cylinder. The ignition coil 11 has its high voltage generation timing controlled via a power transistor 13 attached thereto, and controls the on / off timing of the power transistor 13 by an ignition signal output from the control unit 22. The ignition timing is controlled, and these spark plugs 10, ignition coils 11,
The distributor 12, the control unit 22, etc. constitute an ignition device.

The distributor 12 has a photoelectric crank angle sensor.
Built in 14. This photoelectric crank angle sensor 14
It is composed of a signal disk plate 16 that rotates integrally with the distributor shaft 15 and a detection section 17, and the signal disk plate 16 has 180 position signal (2 ° signal) slits 18 and the number of cylinders of the engine 1. The same number (4 in the case of 4 cylinders) of slits 19 for reference signals (180 ° signal in the case of 4 cylinders) are formed. still,
One of the reference signal slits 19 also serves as a slit for discriminating the first cylinder.

Here, the detection unit 17 detects the slits 18 and 19 and outputs a position signal and a reference signal including a cylinder discrimination signal. Therefore, the engine rotation speed N can be obtained by measuring the period of the reference signal or counting the number of input position signals per unit time. Therefore, the crank angle sensor 14 determines the rotation phase (crank angle) of the crankshaft. Not only does it function as a means for detecting the engine speed N. Therefore, the photoelectric crank angle sensor
14, the air flow meter 6 and the like correspond to the engine operating state detecting means.

Reference numeral 21 is a water temperature sensor provided so as to face the water jacket 20 of the engine, and the engine cooling water temperature (hereinafter referred to as water temperature)
The voltage signal corresponding to is output.

Next, the ignition timing retard control during acceleration according to the present invention will be described with reference to the flowchart of FIG. The functions of the basic ignition timing setting means, the acceleration operation detecting means, the acceleration retard angle correcting means, the retard angle correction prohibition region setting means, the retard angle correction prohibiting means, and the ignition signal output means are shown in the flowchart of FIG. The control unit 22 is provided with software as shown in FIG.

Step (denoted as S in the figure, the same applies hereinafter) 1
Then, signals corresponding to various operating states output from the respective sensors are input.

In step 2, based on the intake air flow rate Q detected by the air flow meter 6 and the engine rotation speed N calculated based on the signal from the photoelectric crank angle sensor 14, the basic fuel injection amount Tp (= K × Q / N; K is a constant) is calculated.

Since the basic fuel injection amount Tp is normally calculated by the control routine for calculating the final fuel injection amount Ti, the calculation result may be input.

In step 3, the basic fuel injection amount Tp corresponding to the engine addition
The basic fuel injection amount calculated in step 2 from the map of the ignition timing (basic ignition timing indicating how many crank angle positions before top dead center) ADV that is preset and stored in accordance with the engine speed N Based on Tp and the engine speed N based on the signal from the photoelectric crank angle sensor 14 input in step 1, the data of the ignition timing ADV corresponding to the operating state is searched. This step 3 corresponds to the basic ignition timing setting means.

In step 4, the acceleration operation state of the engine 1 is determined by whether or not the change in the opening α of the throttle valve 7 detected by the throttle sensor 8 is a predetermined value or more in the opening direction. This step 4 corresponds to the acceleration operation detecting means.

Here, if it is determined that the engine 1 is in the accelerated operation state,
In step 5, it is determined whether or not the acceleration determination is the first time. When the first determination is made, the process proceeds to step 6, and when it is determined that it is not the first time, it is determined in step 4 that the engine 1 is not in the acceleration operation state. Same as step 11
Go to.

When the process proceeds from step 5 to step 6, the retardation control determination level opening α _s preset according to the engine speed N is set.
Is calculated based on the current engine speed N. The retard control determination level opening α _s is the engine speed N at that time.
In the above, the boundary opening α is a region where the intake air flow rate Q hardly changes even if the throttle valve 7 is further opened (hereinafter referred to as the Q flat region), and this step 6 corresponds to the retard correction inhibition region setting means. .

In the next step 7, the current throttle valve opening α detected by the throttle sensor 8 is compared with the retardation control determination level opening α _s obtained in step 6, and the current throttle valve opening α is delayed. When it is larger than the angle control determination level opening α _s (α ≧ α _s ), the current operating state is in the Q flat region and the intake air flow rate Q hardly changes even if the throttle valve 7 is opened. Ignition timing ADV
On the other hand, the control jumps to step 15 without performing the retard control, and controls the on / off timing of the power transistor 13 so that the ignition is performed at the ignition timing ADV set in step 3. Therefore, step 7 corresponds to retard correction inhibiting means, and step 15 corresponds to ignition signal outputting means.

On the other hand, if it is determined in step 7 that the current throttle valve opening α is less than the retardation control determination level opening α _s (α <α _s ), the routine proceeds to step 8 and the acceleration operation state (throttle A retard correction amount (retard correction crank angle) ADV _RET is set according to the valve opening change rate Δα, etc., and the flag is set to 1 in the next step 9.

In step 10, the retard correction amount ADV _RET set in step 8 is subtracted from the ignition timing ADV set in step 3 to perform retard correction, and a new ignition timing ADV is set.
This step 10 corresponds to a retard angle correction means during acceleration.

That is, when the operation state at the initial acceleration determination is in the Q flat region, retardation correction of the ignition timing ADV is not performed even at the beginning of acceleration, and hesitation is prevented from occurring due to the retardation correction of the ignition timing ADV. When it is not in the flat region, the ignition timing ADV is retarded to prevent the occurrence of acceleration shock.

Ignition timing, not the Q flat region, at the first acceleration judgment
When the retard correction of ADV is performed, the processing in steps 11 to 13 is performed from the next time onward, and the ignition timing ADV with the retard correction is calculated from the map according to the basic fuel injection amount Tp and the engine rotation speed N. The ignition timing ADV is gradually approximated.

That is, when the ignition timing AVD is retarded at the first acceleration determination, the flag is set to 1 in step 9. Therefore, when the process proceeds to step 11 next time, the flag is determined to be 1 Go to 12.

In step 12, by subtracting the predetermined angle β from the previous retard correction amount ADV _RET and newly setting the retard correction amount ADV _RET , the retard correction amount becomes smaller than the previous amount by the predetermined angle β. To do.

Then, in step 13, it is determined whether or not the value obtained by subtracting the predetermined angle β from the previous retard correction amount ADV _RET is a value close to zero, and if it is determined to be a value near zero, step Proceed to 14 to set the flag to zero and return to normal ignition timing control.

On the other hand, when the subtraction result in step 12 is not a value near zero, the process proceeds to step 10, and the ignition timing ADV is retarded using the retard correction amount ADV _RET newly set in step 12.

Thus, in the first acceleration detection, whether or not it is in the Q flat region is determined based on the throttle valve opening α and the engine speed N at that time, and when it is in the Q flat region, retard correction is performed. Instead, the ignition timing is controlled according to the ignition timing ADV obtained from the basic fuel injection amount Tp and the engine rotation speed N, and when not in the Q flat region, the retard angle is corrected according to the acceleration state at that time, and then from Tp and N. Delay angle correction amount ADV so that it gradually approaches the required ignition timing ADV
_RET is set small.

Therefore, it is possible to avoid the occurrence of hesitation without retard correction at the time of acceleration in the Q flat region where the change of the intake air flow rate Q is small, in other words, the rise of the engine torque is slow, and the intake air flow rate Q is Prevents the occurrence of acceleration shock by correcting the ignition timing ADV at the time of acceleration detection in an operating region (other than the Q flat region) where the rise of the engine torque during acceleration is rapid in response to changes in the throttle valve opening To do.

<Advantages of the Invention> As described above, according to the present invention, there is no correction of the ignition timing retardation during acceleration from the Q flat region, and it is possible to improve the acceleration drivability by avoiding the occurrence of hesitation. There is.

[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, and FIG. 3 is a flowchart showing ignition timing control in the same embodiment. 1 ... Engine, 6 ... Air flow meter, 7 ... Throttle valve, 8 ... Throttle sensor, 10 ... Spark plug, 11 ...
Ignition coil, 12 …… Distributor, 14 …… Photoelectric crank angle sensor, 22 …… Control unit

Claims (1)

[Scope of utility model registration request] 1. A throttle valve opening detecting means for detecting an opening of a throttle valve provided in an intake passage of an internal combustion engine, and a change rate of the throttle valve opening detected by the throttle valve opening detecting means. Acceleration operation detection means for detecting the acceleration operation of the engine based on, engine operation state detection means for detecting the engine operation state including at least the engine rotation speed, the basic ignition timing corresponding to the steady operation state according to the engine operation state The basic ignition timing setting means for setting and the basic ignition timing set by the basic ignition timing setting means for a predetermined period after the acceleration operation is detected at least on condition of the acceleration detection by the acceleration operation detecting means is retarded according to the acceleration state. Ignition device ignites at the ignition timing corrected or corrected by the acceleration retard correction means, the basic ignition timing setting means, and the acceleration retard correction means. An ignition signal output means for outputting the item,
Delay angle correction prohibition region setting means for setting a throttle valve opening region for prohibiting retard angle correction according to the engine speed, and detection by the throttle valve opening degree detection means at the first time of acceleration operation detection by the acceleration operation detection means When the throttle valve opening is within the throttle valve opening range set by the retard correction prohibited area setting means, the retard correction for prohibiting the ignition timing retard correction by the acceleration retard correction means An ignition timing control device for an internal combustion engine, comprising: prohibiting means.