JP2825524B2 - Ignition timing control method for internal combustion engine - Google Patents

Description

The present invention relates to a method for controlling the ignition timing of an internal combustion engine.

2. Description of the Related Art Conventionally, as a method of controlling an ignition timing of an internal combustion engine, a basic ignition advance, that is, an MBT (Minimun Spark for Best Torque) has been previously determined according to the rotation speed and load of the internal combustion engine. A configuration is used in which the basic ignition advance is corrected and the actual ignition advance is obtained in accordance with the warm-up state of the internal combustion engine, the state of the air-heat ratio, the temperature of the cooling water, or the like. I have.

Here, in a typical prior art, the final advance value actually used for ignition timing control is AOP, and a basic advance term obtained on the basis of the rotational speed, load state, and the like of the internal combustion engine is AB.
SE, the advance correction term determined based on the cooling water temperature and the like is ACLD, the retard correction term corresponding to the rotational acceleration of the internal combustion engine is ATRN, the retard correction term corresponding to the occurrence of knocking is AKNK, The retard correction term corresponding to the shifting operation of the transmission
When ATRQ is set, the final advance value AOP is obtained from the following equation: AOP = ABSE + ACLD- (ATRN + AKNK + ATRQ) (1)

Accordingly, for example, the speed change operation of the transmission is performed during acceleration while accelerating uphill, and the retard correction term ATRN, AKN
In the case where K and AIRQ are all satisfied, if the ignition timing control is performed using the final advance value AOP obtained as described above, the ignition timing will be excessively retarded, and the output of the internal combustion engine will increase significantly. Will decrease.

Another prior art for solving the above-mentioned problem is disclosed in Japanese Patent Application Laid-Open No. 59-201970. In this prior art,
A retard amount related to the temperature of the internal combustion engine, such as a cooling water temperature,
A retard amount corresponding to the load state of the internal combustion engine is calculated and obtained, and a smaller value of the two retard amounts thus obtained is subtracted from the basic advance term ABSE to obtain a final advance. Value AO
Seeking P. For this reason, knocking due to an over-advance angle is likely to occur, and a failure is likely to occur in the internal combustion engine.

An object of the present invention is to prevent a decrease in the output of an internal combustion engine due to an excessive retard angle, to prevent a decrease in the reliability of the internal combustion engine due to an excessive advance angle, and to optimize the advance according to the state of the internal combustion engine. An object of the present invention is to provide a method for controlling an ignition timing of an internal combustion engine that can perform angle control.

Means for Solving the Problems The present invention relates to an ignition timing control method for an internal combustion engine in which an advance term is corrected by a sum of a plurality of retard correction terms including at least a retard correction term for acceleration to obtain a final ignition advance. The present invention provides an ignition timing control method for an internal combustion engine, wherein, during acceleration, a final ignition advance is obtained by correcting an advance term by a maximum retard correction term among the plurality of retard correction terms.

Further, according to the present invention, the advance term is a basic advance term ABSE obtained based on a rotational speed of the internal combustion engine, a load state, and the like.
And the advance correction term AC obtained based on the cooling water temperature, etc.
A first correction term ATRN corresponding to the rotational acceleration of the internal combustion engine, a second correction term AKNK corresponding to the occurrence of knocking, and a third correction term AKNK corresponding to the shift operation of the transmission. Correction term ATRQ
And characterized in that:

Also, according to the present invention, when the first correction term ATRN is equal to or less than a predetermined value, the retard correction term is changed to the first to third correction terms ATRN, AKNK,
When the first correction term ATRN is larger than the predetermined value, the retard correction term is obtained from each of the first to third correction terms ATRN, A.
It is characterized by selecting the largest correction term among KNK and ATRQ.

According to the present invention, the ignition timing of the internal combustion engine is determined by the final ignition advance obtained by correcting the advance term with the retard correction term. The retardation correction term is composed of a plurality of retardation correction terms, and the correction term includes at least a retardation correction term for acceleration. By detecting whether or not the internal combustion engine is in an accelerating state, during acceleration, the advancing term is corrected by the maximum retarding correction term. It is possible to prevent the retard control from being performed excessively.

According to the invention, the advance angle term is a basic advance angle term obtained based on the rotational speed of the internal combustion engine, the state of the load, and the like.
ABSE and an advance correction term ACLD obtained based on the cooling water temperature, etc., and the retard correction term is a correction term ATRN corresponding to the rotational acceleration of the internal combustion engine, and occurrence of knocking. And a correction term ATRQ corresponding to the shift operation of the transmission.

Furthermore, for example, the retardation correction term is a correction term ATRN
Is less than a predetermined value, all correction terms ATRN, AKN
When the correction term ATRN is larger than the predetermined value, the largest correction term is selected from all the correction terms ATRN, AKNK, ATRQ.

Therefore, during steady-state running in which the correction term ATRN is equal to or less than a predetermined value, the retard correction amount is obtained from the sum of the correction term AKNK and the correction term ATRQ, and therefore, the over-advance angle does not occur.
The occurrence of knocking of the internal combustion engine can be suppressed, and the failure occurrence rate of the internal combustion engine can be reduced. Further, when the correction term ATRN is larger than a predetermined value, the correction term ATRN and the correction term AKNK
The largest correction term among the correction term ATRQ is used as the retardation correction term. Therefore, each correction term ATRN, AKNK, ATRQ
The excessive retardation due to the cooperation of the above can be prevented, and the decrease in the output of the internal combustion engine can be suppressed.

Embodiment FIG. 1 is a block diagram showing a control device 1 for an internal combustion engine using an ignition timing control method according to an embodiment of the present invention and a configuration related thereto. The combustion air introduced from the intake port 2 is purified by the air cleaner 3, the flow rate of the combustion air is adjusted from the intake pipe 4 by the throttle valve 5 interposed in the intake pipe 4, and then flows into the surge tank 6. Surge tank 6
The combustion air flowing out of the engine is mixed with fuel injected from a fuel injection valve 8 interposed in an intake pipe 7 and supplied to a combustion chamber 11 of an internal combustion engine 10 through an intake valve 9. An ignition plug 12 is provided in the combustion chamber 11, and the combustion exhaust gas from the combustion chamber 11 is discharged through an exhaust valve 13, and is discharged from the exhaust pipe 14 to the atmosphere via a three-way catalyst 15.

The intake pipe 4 is provided with an intake air temperature detector 21 for detecting the temperature of intake air, the throttle valve 5 is provided with a throttle valve opening detector 22, and the surge tank 6 is provided with an intake pressure detector 23. Provided. In the vicinity of the combustion chamber 11,
A cooling water temperature detector 24 and a knocking detector 37 realized by an acceleration sensor or the like are provided. In the exhaust pipe 14, an oxygen concentration detector 25 is provided upstream of the three-way catalyst 15, and an exhaust temperature detector 26 is provided downstream of the three-way catalyst 15. The rotational speed and rotational acceleration of the internal combustion engine 10 are detected by a crank angle detector 27.

In the control device 1, together with the detectors 21 to 27, 37,
A vehicle speed detector 28, a start detector 29 that detects whether a starter motor 33 that starts the internal combustion engine 10 has been started, and an air conditioning detector 30 that detects use of a cooling machine,
When the vehicle equipped with the internal combustion engine 10 is equipped with an automatic transmission, a detection result from a neutral detector 31 for detecting whether or not the gear position of the automatic transmission is at a neutral position is input. Furthermore, this control device 1
Is energized by a battery 34, and the control device 1 controls the detection results of the detectors 21 to 31, 37 and the power supply voltage of the battery 34 detected by the voltage detector 20. The fuel injection amount, the ignition timing, and the like are calculated based on the calculated values, and the fuel injection valve 8, the ignition plug 12, and the like are controlled.

The intake pipe 4 is also provided with a bypass 35 that bypasses the upstream and downstream sides of the throttle valve 5, and the bypass 35 is provided with a flow control valve 36. The flow control valve 36 controls the flow rate of the combustion air at the time of idling when the throttle valve 5 is almost fully closed, based on the output from the control device 1. The control device 1 also drives the fuel pump 32 when the internal combustion engine 10 is operating.

FIG. 2 is a block diagram showing a specific configuration of the control device 1. The detection results of the detectors 20 to 25 are provided from an input interface circuit 41 to a processing circuit 43 as ignition timing control means via an analog / digital converter 42.
The detection results of the detectors 22, 27 to 31, 37 are supplied to the processing circuit 43 via an input interface circuit 44. The processing circuit 43 is provided with a memory 45 for storing various control maps and learning values, which will be described later, and the processing circuit 43 receives the power from the battery 34 through a constant voltage circuit 46. Is supplied via

The control output from the processing circuit 43 is derived through an output interface circuit 47, and is applied to the fuel injection valve 8 to control the amount of fuel injection, and is also applied to an ignition plug 12 via an igniter 48 for ignition. The timing is controlled, and the flow is supplied to the flow control valve 36 to control the flow rate of the inflowing air through the bypass 35 during idling. The exhaust gas temperature detector 26
Is given to the exhaust gas temperature detection circuit 49 in the control device 1, and when the detection result is abnormally high, the warning lamp 51 is turned on via the drive circuit 50.

In the control device 1 configured as described above, the basic advance term ABSE is calculated based on the rotational speed NE of the internal combustion engine 10 detected by the crank angle detector 27, for example, the rotational speed NE, and the intake pressure detector. In the processing circuit 43, the memory 45 is stored in the processing circuit 43 from the intake pressure detected by the throttle valve 23 and the intake air flow rate Q determined based on the throttle valve opening detected by the throttle valve opening detector 22. Stored third
The three-dimensional map shown in FIG.

Further, the advance correction term AC at the time of warm-up operation of the internal combustion engine 10, etc.
The LD is stored in the memory 45 in the processing circuit 43 from the cooling water temperature THW detected by the cooling water temperature detector 24, and is obtained based on the graph shown in FIG. That is, for example, when the cooling water temperature THW is equal to or lower than −20 ° C., the advance correction term ACLD is, for example, a 10 ° crank angle (hereinafter referred to as “ΔCA”), and
The cooling water temperature THW decreases from 0 ° C. and decreases as the cooling water temperature THW increases.

Further, the processing circuit 43 is stored in the memory 45 from the predetermined rate of change ΔPM per unit time of the intake pressure PM detected by the intake pressure detector 23, and FIG.
The retard correction term ATRN is obtained based on the graph shown by the following equation, and the retard correction term ATRN changes within a range of, for example, 0 to 10 CA. This correction term ATRN is, as shown in FIG.
For example, it is reduced by 1 CA for each ignition of the internal combustion engine 10.

As shown in FIG. 6, the processing circuit 43 adds the retardation correction term AKNK by 1 CA when the occurrence of knocking is detected by the knocking detector 37 as shown in FIG. Is not detected, 1 CA is subtracted.

Further, when the processing circuit 43 detects that the gear position of the automatic transmission has been changed from the neutral position to the drive position in response to the output from the neutral detector 31 shown in FIG. As shown in FIG. 7 (2), the retard correction term ATRQ is set to 15 CA, and thereafter, for example, it is decreased by 1 CA every 100 msec.

The angle retardation correction terms ATRN, AKNK, AT thus obtained
FIG. 8 shows the relationship between the RQ, the throttle valve opening, and the intake pressure PM. That is, when the throttle valve 5 is opened at the time t1 as shown in FIG. 8A, the intake pressure PM detected by the intake pressure detector 23 is influenced by the surge tank 6 and the intake pressure PM. Fig. 8 (2) from the response delay of
Changes as shown by.

At time t2 when the intake pressure PM rises and the time rate of change ΔPM of the intake pressure PM becomes equal to or greater than the predetermined value ΔPMth, as shown in FIG. When it is set to a value corresponding to the time change ΔPM shown in FIG. 1A and the acceleration state is no longer detected, as shown in FIG. 5B, 1 ゜ CA per ignition cycle. It is gradually reduced.

Further, the retardation correction amount AKNK is calculated as shown in FIG.
As shown in the drawing, the value is increased by 1 CA every time knocking is detected, and is decreased by 1 CA every 0.5 seconds when no knocking is detected.

Furthermore, at times t3 and t4, the neutral detector 3
According to 1, when the gear position of the automatic transmission is changed from the neutral position to the drive position, at this time t3, the retard correction term ATRQ is shown in FIG. 8 (5) and FIG. 7 (2). To be 15 CA.

Hereinafter, a specific operation for obtaining each of the retard angle correction terms ATRN, AKNK, ATRQ and the final advance value AOP will be described. FIG. 9 and FIG. 10 are flowcharts for explaining the operation for obtaining the retard correction term ATRN. The intake pressure PM detected by the intake pressure detector 23 is digitally converted by the analog / digital converter 42 and read into the processing circuit 43. In step n1, the time change rate ΔPM of the intake pressure PM is obtained. It is determined whether the time rate of change ΔPM exceeds a predetermined value ΔPMth, that is, whether the vehicle is accelerating,
If so, the retard angle correction term ATRN is set to 10 ゜ in step n2.
CA is substituted and the operation moves to another operation. In step n1, when the time rate of change ΔPM of the intake pressure PM is equal to or less than the predetermined value ΔPMth, the operation directly proceeds to another operation. This step
The setting operation of the retard correction term ATRN during acceleration indicated by n1 and n2 is performed, for example, every time the analog / digital conversion operation is performed every 2 msec.

On the other hand, every time the ignition control of the internal combustion engine 10 is performed, step n3 is performed.
Then, the retard correction term ATRN is updated by subtracting 1 CA, and the operation proceeds to another operation. By repeating this step n3, the retard correction term AT is obtained as shown in FIG.
RN gradually decreases.

FIG. 11 and FIG. 12 are flowcharts for explaining the operation for obtaining the retardation correction term AKNK. When the vibration of the internal combustion engine 10 is detected by the knocking detector 37, the processing circuit 43 proceeds to a knock determination operation, and performs a step.
At n11, whether or not knocking has occurred is determined based on whether or not the output of the knocking detector 37 is equal to or higher than a predetermined knock determination level. When occurrence of knocking is detected in step n11, 1 ゜ CA is added to the retard correction term AKNK and updated in step n12, and the operation proceeds to another operation. If it is determined in step n11 that the detected vibration is not knocking, the operation directly proceeds to another operation.

If no vibration is detected by the knocking detector 37 every 0.5 seconds, the retard correction term AKNK is set in step n13.
Is updated by subtracting 1 CA from. At step n14, it is determined whether or not the updated retard correction term AKNK is 0 or more. If not, at step n15, after the retard correction term AKNK is reset to 0, the operation proceeds to another operation. If the retard correction term AKNK is equal to or greater than 0 in step n14, the operation directly proceeds to another operation. In this way, the retard correction term AKNK that changes as shown in FIG. 6 can be obtained.

FIG. 13 and FIG. 14 are flowcharts for explaining the operation for obtaining the retard correction term ATRQ. The output of the neutral detector 31 is detected at a predetermined cycle by the processing circuit 43, and at step n21, it is determined whether or not the gear position of the transmission has been shifted from the neutral position to the drive position. If so, at step n22, 15 ° CA is substituted for the retard correction term ATRQ and the operation proceeds to another operation. Otherwise, the operation directly proceeds to another operation. The retard correction term ATRQ is updated by subtracting 1 CA from every 100 mesc in step n23. Thus, the retard correction term ATRQ shown in FIG. 7 (2) can be obtained.

Each of the retard correction terms ATRN, AKNK,
Using the ATRQ, a final advance value AOP used for actual ignition timing control is calculated by the operation shown in FIG.
In step n31, an intake air flow rate Q calculated and calculated based on the rotational speed NE of the internal combustion engine 10 detected by the crank angle detector 27 and the intake pressure PM detected by the intake pressure detector 23. And the rotational speed NE, the basic advance term ABSE is obtained based on the graph shown in FIG.

In step n32, the advance correction term ACLD is obtained from the coolant temperature THW detected by the coolant temperature detector 24 based on the graph shown in FIG. Step n3
In step 3, the basic advance term ABSE obtained in step n31 is used.
And the sum of the advance angle correction term ACLD obtained in step n32 is calculated and stored in the register B as the advance amount.

In step n34, it is determined whether or not the retard correction term ATRN obtained by the operation shown in FIGS. 9 and 10 is a predetermined value 0. If so, that is, the steady state is continued. If so, the process proceeds to step n35, where the sum of the respective retard correction terms ATRN, AKNK, ATRQ is obtained and stored in the register A. At step n36, the stored contents of the register A are subtracted from the stored contents of the register B, the final advance value AOP is calculated, and the operation ends.

When the retard correction term ATRQ is not 0 in step n34, that is, when the acceleration state or immediately after the end of the acceleration state, the process proceeds to step n37 to determine whether the retard correction term ATRN is larger than the retard correction term AKNK. If so, in step n38, the retard correction term ATRN is stored in the register A and proceeds to step n40, otherwise, in step n39 the retard correction term AKNK is stored in register A and proceeds to step n40.

In step 40, it is determined whether or not the stored content of the register A is larger than the retard correction term ATRQ. If so, in step n41, the stored content of the register A is replaced with the retard correction term ATRQ and the process proceeds to step n36. If not, go directly to step n36 from step n40.

In this manner, during acceleration when the retard correction term ATRN is not zero, in steps n37 to 41, each of the retard correction terms ATRN and AKN
After the largest delay correction term is selected from K and ATRQ,
At step n36, the final advance value AOP is calculated by subtracting from the advance term stored in the register B. That is, AOP = ABSE + ACLD-MAX (ATRN, AKNK, ATRQ) (2) Thus, during steady operation of the internal combustion engine 10, the sum of the retard angle correction terms ATRN, AKNK, ATRQ obtained in FIGS. Thus, in the transient state of the internal combustion engine 10 such as during acceleration, the retard control is performed by the largest retard correction term among the above-described retard correction terms ATRN, AKNK, ATRQ.

Accordingly, the unnecessary retard control in the case where the conditions of the respective retard corrections are likely to be satisfied, such as when the speed of the transmission is accelerated in the first speed, is suppressed, and the output of the internal combustion engine 10 is reduced. Can be prevented. Further, during steady running, there is no over-advance angle, and the occurrence of knocking can be suppressed, and the failure occurrence rate of the internal combustion engine 10 can be reduced. Furthermore, the ignition timing control operation shown in FIG. 15 can be realized by a relatively simple calculation processing operation as compared with a method of setting an upper limit and a lower limit for the retard correction amount.

Effects of the Invention As described above, according to the present invention, the retardation correction term for correcting the advancement term is constituted by a plurality of retardation correction terms including at least the retardation correction term for acceleration. In response to whether or not the vehicle is in an acceleration state, it is possible to prevent excessive retard control due to a sudden change in the plurality of correction terms during acceleration.

According to the invention, the advance angle term is a basic advance angle term obtained based on the rotational speed of the internal combustion engine, the state of the load, and the like.
ABSE and an advance correction term ACLD obtained based on the cooling water temperature and the like, and the retard correction term corresponds to a correction term ATRN corresponding to the acceleration of the internal combustion engine, and corresponds to occurrence of knocking. A correction term AKNK and a correction term ATRQ corresponding to a shift operation of the transmission are configured. Further, for example, when the correction term ATRN is zero, all of the correction terms ATRN, AKNK , ATRQ, the correction term ATRN
When is not zero, among the correction terms ATRN, AKNK, ATRQ,
Since the largest correction term is selected, an over-advance angle does not occur during steady running, so that the occurrence of knocking can be suppressed and the failure occurrence rate of the internal combustion engine can be reduced. Further, during acceleration, the excessive retardation due to the cooperation of the correction terms ATRN, AKNK, ATRQ can be prevented, and a decrease in the output of the internal combustion engine can be suppressed.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a control device 1 of an internal combustion engine using an ignition timing control method according to an embodiment of the present invention and a configuration related thereto, FIG. 2 is a block diagram showing a specific configuration of the control device 1, FIG. 3 is a graph showing the relationship between the rotational speed control NE of the internal combustion engine 10, the intake air amount Q, and the basic advance term ABSE. FIG. 4 is a graph showing the relationship between the coolant temperature THW and the advance correction term ACLD. FIG. 5 is a graph showing a change in the retard correction term ATRN, and FIG.
FIG. 7 is a graph showing the change in the retard correction term AKNK, FIG. 7 is a graph showing the change in the retard correction term ATRQ, and FIG. 8 is a change in the throttle valve opening and the intake pressure PM and the retard correction term ATRN, AKNK. , ATRQ
9 to 15 are flowcharts for explaining the ignition timing control operation. DESCRIPTION OF SYMBOLS 1 ... Control device, 10 ... Internal combustion engine, 20-31, 37 ... Detector, 43 ... Processing circuit, 45 ... Memory, 48 ... igniter

──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Tatsuyuki Sugiyama 1 Toyota Town, Toyota City, Aichi Prefecture Inside Toyota Motor Corporation (58) Field surveyed (Int.Cl. ⁶ , DB name) F02P 5/15 F02P 5/152

Claims (3)

(57) [Claims] 1. An ignition timing control method for an internal combustion engine for obtaining a final ignition advance by correcting an advance term by a sum of a plurality of retard correction terms including at least a retard correction term for acceleration. An ignition timing control method for an internal combustion engine, wherein a final ignition advance is obtained by correcting an advance term by a maximum retard correction term among retardation correction terms. 2. The advance term includes a basic advance term ABSE obtained based on a rotational speed of the internal combustion engine, a state of a load, and the like, and an advance correction term ACLD obtained based on a coolant temperature and the like. The retard correction term includes a first correction term ATRN corresponding to the rotational acceleration of the internal combustion engine, a second correction term AKNK corresponding to the occurrence of knocking, and a third correction term ATRQ corresponding to the shift operation of the transmission.
2. The ignition timing control method for an internal combustion engine according to claim 1, comprising: 3. When the first correction term ATRN is equal to or less than a predetermined value, the retard correction term includes first to third correction terms ATRN, AKNK, ATRQ.
When the first correction term ATRN is larger than the predetermined value, the retard correction term is set to the first to third correction terms ATRN, AKNK,
3. The ignition timing control method for an internal combustion engine according to claim 2, wherein the largest correction term is selected from ATRQ.