JP2002031024A - Ignition timing controller for internal combustion engine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an ignition timing controller for an internal combustion engine capable of determining an ignition period for controlling the knock regardless of the load and an intake temperature of the internal combustion engine. SOLUTION: An α deg.C maximum lag ignition period akmf is calculated on the basis of an engine rotating speed NE and an engine load factor, and a maximum lag correction amount akmftha is calculated by executing the interpolating operation in reference to a map on the basis of the intake temperature and the engine load factor. The maximum lag amount akmax from the basic ignition period absef is calculated on the basis of a formula: akmax= akmf-absef+akmftha.

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 device for controlling an ignition timing according to an operating state of an internal combustion engine.

[0002]

2. Description of the Related Art Conventionally, the ignition timing of an internal combustion engine (engine) is one of the factors that greatly affect the exhaust gas, fuel efficiency, drivability (output torque of the engine), etc. of the engine. Therefore, it is necessary to control the ignition timing so as to be an optimal timing according to the operation state of the internal combustion engine. In a basic ignition timing control device that performs this type of control, a computer calculates an optimum ignition timing based on the operating state of the engine, for example, the rotation speed and load of the engine, and turns on the ignition plug at the calculated ignition timing. Activate.

Incidentally, as an ignition timing control device, in order to extract the maximum output torque in the operating state of the engine, as shown in FIG. 5, the knocking limit ignition timing at which the engine starts to knock as shown in FIG. 5 (line (a)) And the final ignition timing is controlled near the α ° knock limit ignition timing. The α ° knock limit ignition timing is determined according to the engine load at the intake air temperature α ° C. To perform such ignition timing control, as shown in FIG. 5, a basic ignition timing absef (> 0) is calculated based on the engine speed and the engine load. Also,
The α ° C. maximum retarded ignition timing akmf (> 0), which is retarded by a predetermined amount from the α ° knock limit ignition timing determined according to the operating state of the engine 11, is calculated. Thereafter, the maximum retardation amount akmax ′ (<0) from the basic ignition timing absef is calculated by subtracting the basic ignition timing absef from the α ° C most retarded ignition timing akmf. Next, the knock learning value akg (> 0) calculated based on the advance of the α ° most retarded ignition timing akmf based on the engine knock detection and the correction amount akcs (<0) are maximum retarded. Quantity akmax '
To calculate the retard amount akkn (<0) from the basic ignition timing absef. Then, the final ignition timing aop is calculated by adding the retard amount aknk to the basic ignition timing absef. From another viewpoint, the final ignition timing aop is α according to the load at that time.
Knocking learning value akg for ° C most retarded ignition timing akmf
And the correction amount akcs. Therefore, when the engine load changes suddenly, the knock learning value akg
The final ignition timing aop is calculated by adding the knock learning value akg and the correction amount akcs to the α ° most retarded ignition timing akmf corresponding to the load at that time. In this case, the final ignition timing aop falls within the range of the knock limit ignition timing indicated by the line (a), and it is possible to suppress the generation of knock and to suppress the decrease in output torque.

[0004]

However, the inventor of the present application filed a β ° C knock limit ignition timing (line (b) in FIG. 5) when the intake air temperature of the engine is high (for example, β ° C) when the vehicle is suitable for an actual vehicle. ) Is lower than the α ° knock limit ignition timing, and furthermore, the retard amount is insufficient at the α ° maximum retard ignition timing akmf, and the engine knock is not extinguished. As shown in FIG. 5, the difference between the β ° knock limit ignition timing and the α ° knock limit ignition timing is larger on the small load side than on the large load side. β ℃ knock limit ignition timing is α ℃ most retarded ignition timing akm on the heavy load side
Although the value is larger than f, on the small load side, the β ° knock limit ignition timing is smaller than the α ° most retarded ignition timing akmf. Therefore, α ℃ only by knock learning
If the difference between the knock limit ignition timing and the β ° knock limit ignition timing is absorbed, the parallelism between the α ° knock limit ignition timing and the maximum retard amount may be broken, and the knock learning principle may not be established.

FIG. 6 shows the influence on the knock limit based on the intake air temperature and the amount of retardation from the basic ignition timing when the engine load is set to a predetermined value. In FIG. 6, the normal retard width (most retarded ignition timing akmf) is θ0 (° CA).
It is. The sensitivity SEN to the knock limit with respect to the intake air temperature is large, and when the intake air temperature exceeds TB, the most retarded ignition timing akm
At f, the amount of retardation is insufficient, and knock occurs in the shaded area.

The present invention has been made in view of the above circumstances, and has as its object to set an ignition timing capable of suppressing knocking regardless of the load and intake air temperature of the internal combustion engine. To provide an ignition timing control device.

[0007]

The means for achieving the above object and the effects thereof will be described below. According to a first aspect of the present invention, there is provided a basic ignition timing calculating means for calculating a basic ignition timing of an internal combustion engine according to an operation state of the internal combustion engine, and a knock limit ignition timing previously obtained according to an operation state of the internal combustion engine. A most retarded ignition timing calculating means for calculating a most retarded ignition timing delayed by a predetermined amount; and a maximum retarded amount from the basic ignition timing by subtracting the basic ignition timing from the most retarded ignition timing. And a knock learning value calculated based on the advance amount from the most retarded ignition timing based on the knock detection of the internal combustion engine is added to the maximum retard amount. A retard amount calculating means for calculating a retard amount according to the operating state, and a final ignition timing calculating means for calculating a final ignition timing by adding the retard amount to the basic ignition timing. The point of equipped internal combustion engine In timing control device, the maximum retard amount calculating means summarized as further comprising a correction means for correcting, based an the maximum retardation amount to environmental conditions and engine load.

[0008] In an internal combustion engine, the knock limit ignition timing may shift from the basic ignition timing to the retard side depending on the environmental conditions in which the internal combustion engine is used and changes in the engine load.
For this reason, the maximum retardation amount calculated by subtracting the basic ignition timing from the most retarded ignition timing may cause the case where the retardation amount is insufficient, and may not be able to suppress the occurrence of knock. On the other hand, according to the first aspect of the present invention, the maximum retard amount is corrected based on the environmental condition and the engine load. Therefore, the corrected maximum retard amount depends on the environmental condition and the engine load. Insufficiency of the retard amount with respect to the corresponding knock limit ignition timing can be prevented, and the occurrence of knock can be suppressed.

According to a second aspect of the present invention, in the ignition timing control device for an internal combustion engine according to the first aspect, the environmental condition is an intake air temperature of the internal combustion engine. Since the influence of the intake air temperature on the knock limit ignition timing is large, by correcting the maximum retardation amount based on the intake air temperature as in the second aspect of the present invention, the corrected maximum retardation amount becomes equal to the intake air temperature. Insufficiency of the retard amount with respect to the corresponding knock limit ignition timing can be prevented, and the occurrence of knock can be appropriately suppressed.

According to a third aspect of the present invention, in the ignition timing control device for an internal combustion engine according to the second aspect, the correction means increases the maximum retard amount as the engine load decreases, and increases the intake air temperature. The gist is that the correction is made so as to increase the maximum retard amount as much as possible.

In an internal combustion engine, the knock limit ignition timing shifts from the basic ignition timing to the retard side as the intake air temperature increases or the engine load decreases. For this reason, the maximum retardation amount calculated by subtracting the basic ignition timing from the most retarded ignition timing may cause the retardation amount to be insufficient. On the other hand, according to the invention of claim 3, since the maximum retard amount is increased as the engine load decreases, the maximum retard amount is corrected so as to increase as the intake air temperature increases. The corrected maximum retard amount does not become insufficient with respect to the knock limit ignition timing according to the intake air temperature and the engine load, and the occurrence of knock can be appropriately suppressed.

According to a fourth aspect of the present invention, in the ignition timing control apparatus for an internal combustion engine according to the third aspect, the correction means corrects the maximum retardation amount by correcting the most retarded ignition timing. The point is to do.

According to a fourth aspect of the present invention, by correcting the most retarded ignition timing and subtracting the basic ignition timing from the corrected most retarded ignition timing, the maximum retarded amount from the basic ignition timing is corrected. You.

According to a fifth aspect of the present invention, in the ignition timing control apparatus for an internal combustion engine according to the fourth aspect, the most retarded ignition timing calculating means includes an engine load and a most retarded ignition timing at a predetermined intake air temperature. Is stored as internal data, the most retarded ignition timing is calculated from the engine load by referring to the map, and the correction means corrects the intake temperature and the engine load and the correction amount of the most retarded ignition timing. The gist of the present invention is to hold a map relating to (i) as internal data, and to interpolate the correction amount of the most retarded ignition timing from the intake air temperature and the engine load by referring to the map.

According to the fifth aspect of the present invention, a map relating to the engine load and the most retarded ignition timing at a predetermined intake air temperature,
Since a map relating to the intake air temperature, the engine load, and the correction amount of the most retarded ignition timing may be held as internal data, the data amount is small, and the capacity of the memory for storing the data can be reduced.

According to a sixth aspect of the present invention, in the ignition timing control apparatus for an internal combustion engine according to the fourth aspect, the most retarded ignition timing calculating means includes an engine load and a most retarded ignition timing at a predetermined intake air temperature. Is stored as internal data, the most retarded ignition timing is calculated from the engine load by referring to the map, and the correction means determines the engine load and the most retarded ignition timing at the second intake air temperature. The gist of the present invention is to hold a map relating to (i) as internal data, and to interpolate the correction amount of the most retarded ignition timing from the intake air temperature and the engine load by referring to the map.

According to the invention of claim 6, a map relating to the engine load and the most retarded ignition timing at a predetermined intake air temperature,
Since a map relating to the engine load and the most retarded ignition timing at the second intake air temperature may be held as internal data,
Since the amount of data is small, the capacity of the memory for storing the data can be reduced.

[0018]

FIG. 1 is a schematic diagram showing a gasoline engine system. A gasoline engine (hereinafter simply referred to as “engine”) 11 as an internal combustion engine includes a cylinder 13 formed in a cylinder block 12 and a piston 1 reciprocating vertically in the cylinder 13.
5, a combustion chamber 16 defined by a cylinder 13, a cylinder head 14, and an upper surface of a piston 15, a crankshaft 17 as an output shaft of the engine 11, and a reciprocating motion of the piston 15 converted into a rotational motion of the crankshaft 17. And a connecting rod 19 for conversion.

The outside air drawn into the intake passage 26 from an air cleaner (not shown) flows through the intake ports 22 corresponding to the respective cylinders. Injector 28 provided for each cylinder
Injects fuel to each intake port 22. The mixture of the outside air and the fuel is introduced into the combustion chamber 16 when the intake port 22 is opened by the intake valve 24 provided for each cylinder. Further, when the ignition plug 38 provided for each cylinder is operated, the air-fuel mixture explodes and burns in the combustion chamber 16 and the piston 15 is operated, so that the driving force of the engine 11 is obtained. Thereafter, when the exhaust port 23 is opened by the exhaust valve 25 provided for each cylinder, the burned gas is discharged from the combustion chamber 16 to the outside through the exhaust passage as the exhaust gas.

A throttle valve 29 provided in the middle of the intake passage 26 operates in conjunction with operation of an accelerator pedal (not shown) to open and close the intake passage 26. By the operation of the throttle valve 29, the intake air amount Q with respect to the intake passage 26 is adjusted.

An intake air temperature sensor 30 provided in the intake passage 26 near the air cleaner detects the temperature (intake air temperature) THA of the air taken into the intake passage 26 and outputs a signal corresponding to the temperature. . An air flow meter 31 provided in the intake passage 26 near the air cleaner detects an intake air amount Q in the intake passage 26 and outputs a signal corresponding to the amount. A throttle sensor 32 provided near the throttle valve 29 detects the opening degree (throttle opening degree) TA of the throttle valve 29 and outputs a signal corresponding to the opening degree.

A water temperature sensor 33 provided in the cylinder block 12 detects a temperature (cooling water temperature) THW of cooling water flowing for cooling the block 12, and outputs a signal corresponding to the temperature. Further, a knock sensor 34 provided as a knock detection means provided on the cylinder block 12 is provided.
Detects a vibration including knocking generated in the engine 11 and outputs a knock signal corresponding to the magnitude of the vibration. A rotation speed sensor 35 provided near the crankshaft 17 detects the rotation speed (engine rotation speed) N of the engine 11 based on the rotation of the crankshaft 17.
E is detected, and a signal corresponding to the speed is output.

The igniter 36 conducts and cuts off current to and from a primary coil of an ignition coil 37 based on an ignition signal output from an electronic control unit (hereinafter, simply referred to as “ECU”) 40. When the primary current is cut off, high voltage induced on the secondary coil causes a spark discharge in the spark plug 38 to ignite the air-fuel mixture. That is, the ignition timing of the ignition plug 38 is determined by the ignition signal from the igniter 36. In this embodiment, each spark plug 3
8 and the igniter 36 constitute the ignition device of the present invention.

In the engine 11 having such a structure, four strokes of intake, compression, combustion / expansion, and exhaust are performed in the combustion chamber 16 in order to obtain the power. That is, in the intake stroke, a mixed gas of the fuel injected from the fuel injection valve 28 and the air sucked from the intake passage 26 is opened by the opening of the intake valve 24 and the downward movement of the piston 15 so that the intake port It is sucked into the combustion chamber 16 through 22. Next, in the compression stroke, the piston 15 that has reached the bottom dead center moves upward with the closing of the intake valve 24. Thereby, the volume of the combustion chamber 16 is reduced, and the mixed gas filled in the combustion chamber 16 is compressed. In the subsequent combustion / expansion stroke, the ignition plug 3
From 8, a spark is ignited at a predetermined ignition timing, and the compressed mixed gas is ignited. Thereby, the mixed gas in the combustion chamber 16 explodes, and the combustion expansion of the mixed gas pushes down the piston 15 in the direction of the bottom dead center, so that power is applied to the engine 11. Then, in the exhaust stroke, the mixed gas after combustion is sent out from the exhaust port 23 as exhaust gas with the opening of the exhaust valve 25 at a predetermined timing and the upward movement of the piston 15.

In this embodiment, various sensors 3 and the like are used.
0 to 35 constitute an operating state detecting means of the present invention for detecting the operating state of the engine 11. Here, the ECU 4
Reference numeral 0 denotes the basic ignition timing calculation means, the most retarded ignition timing calculation means, the maximum retardation amount calculation means, the retardation amount calculation means, the final ignition timing calculation means and the correction means of the present invention. This ECU 4
0 inputs signals output from the various sensors 30 to 35 described above. The ECU 40 controls each injector 28 and each igniter 36 based on these input signals.

The ECU 40 includes a read-only memory (ROM) in which a predetermined control program and the like are stored in advance, and a central processing unit (CP) that executes the program stored in the ROM.
U), a random access memory (RAM) for temporarily storing the calculation results of the CPU, and a backup RA for storing data to be stored when the engine 11 is stopped.
M and so on.

The ECU 40 reads signals from various sensors 30 to 35 as input values, and executes fuel injection amount control including air-fuel ratio control and ignition timing control including knock control based on the input values. Each member 28, 3
8 and so on.

Here, the fuel injection amount control means that the engine 1
That is, the amount of fuel injected from each injector 28 is controlled in accordance with the first operation state. The air-fuel ratio control is to control the air-fuel ratio in the engine 11. The ignition timing control is to control the igniter 36 in accordance with the operation state of the engine 11 to operate each ignition plug 38 to control the ignition timing of the air-fuel mixture in each combustion chamber 16. Further, the knock control means the knock sensor 3
That is, the occurrence of knocking is determined based on the detection value of No. 4, and the occurrence of knocking is controlled by controlling the ignition timing based on the determination result.

In this embodiment, the RO of the ECU 40
M is a predetermined amount (θ0 in the present embodiment) from the map for calculating the basic ignition timing absef (see FIG. 5) and the α ° knock limit ignition timing (see FIG. 5) obtained according to the operating state of the engine 11. (° CA))
A map for calculating the ° C most retarded ignition timing akmf is stored in advance. Further, in the ROM of the ECU 40, for example, as shown in FIG. 4, a map relating to the intake air temperature and the engine load and the correction amount of the most retarded ignition timing is stored in advance.
In this map, the relationship among the intake air temperatures T1, T2, T3, and T4 is T1 <T2 <T3 <T4. Intake air temperature T1, T
2, the most retarded angle correction amount at T3 (−θ1), (−θ
2), (−θ3), (−θ4), (−θ5), (−θ
6), (−θ7), (−θ8), and (−θ9) are negative values. The correction amount (−θ1) at the intake air temperature T2, (−θ
2), the relationship between (−θ3) is (−θ1) <(− θ2) <
(−θ3), and the correction amount (−θ) at the intake air temperature T3.
4), (−θ5), and (−θ6) have a relationship of (−θ4) <
(−θ5) <(− θ6), and the relationship among the most retarded correction amounts (−θ7), (−θ8), and (−θ9) at the intake air temperature T4 is (−θ7) <(− θ8) <(− θ9). Also,
Correction amount (-θ1), (-θ4), (-θ
The relationship of (7) is (−θ1)> (− θ4)> (− θ7), and the relationship of the correction amounts (−θ2), (−θ5), and (−θ8) is (−θ2)> (− θ5). > (− Θ8), and the relationship among the correction amounts (−θ3), (−θ6), and (−θ9) is (−θ8).
3)> (− θ6)> (− θ9).

The ECU 40 interpolates and calculates the correction amount akmftha of the most retarded ignition timing based on the intake air temperature and the engine load factor by referring to the map shown in FIG. FIG.
The line (d) shown in FIG. 7 shows the β ° C. most retarded ignition timing akmf ′ when the intake air temperature is β ° C., and the β ° C. most retarded ignition timing a
kmf ′ is obtained by adding the correction amount akmftha to the α ° most retarded ignition timing akmf.

In this embodiment, the ECU 40
Calculates the final ignition timing of the engine 11 as follows. First, the ECU 40 determines the basic ignition timing ab based on the engine speed NE and the engine load factor.
sef (> 0) is calculated. Next, the ECU 40 calculates the α ° most retarded ignition timing akm obtained according to the engine load factor.
f (> 0) is calculated. Since the amount of retardation is insufficient at the α ° most retarded ignition timing akmf due to the intake air temperature and the engine load factor of the engine 11, the ECU 40 performs an interpolation calculation based on the intake air temperature and the engine load factor with reference to the map of FIG. As a result, the correction amount akmft of the most retarded ignition timing is obtained.
ha (<0) is calculated, and the calculated correction amount akmft is calculated.
The most retarded ignition timing is calculated by adding ha to the α ° most retarded ignition timing akmf. Thereafter, the ECU 40 determines that α
℃ The most advanced ignition timing akmf to the basic ignition timing absef
Is subtracted from the basic ignition timing absef to calculate the maximum retardation amount akmax (<0) from the basic ignition timing absef. Next, the knock learning value akg (> 0) calculated based on the advance amount from the most retarded ignition timing based on the knock detection of the engine 11 and the correction amount akcs (<0) are converted into the maximum retard amount akmax. To calculate the retard angle amount aknk (<0). Then, the ECU 40 calculates the final ignition timing aop by adding the retardation amount ankk to the basic ignition timing absef.

Next, the operation when the ECU 40 sets the final ignition timing aop will be described with reference to the flowcharts shown in FIGS. The routine shown in FIGS. 2 and 3 is executed at every predetermined rotation angle (for example, at every 180 ° CA in a four-cylinder internal combustion engine). FIG. 2 shows a procedure for calculating a maximum retard amount used in the ignition timing calculation processing, and FIG. 3 shows a procedure for the ignition timing calculation processing.

First, the processing for calculating the maximum retard amount in FIG. 2 will be described. In step 110, based on the engine speed NE obtained from the detection signal of the rotation speed sensor 35 and the engine load factor calculated from the intake air amount Q obtained from the detection signal of the air flow meter 31, the α ° C most retarded ignition timing akmf ( (See FIG. 5).

In step 120, an interpolation operation is performed by referring to the map of FIG. 4 based on the intake air temperature obtained from the detection signal of the intake air temperature sensor 30 and the engine load factor, thereby obtaining the most retarded angle correction amount shown in FIG. akmftha is calculated.

Then, at step 130,
Based on the maximum ignition timing a from the basic ignition timing absef
Calculate kmax.

[0036]

## EQU00001 ## akmax = akmf-absef + akmftha Next, the ignition timing calculation process of FIG.

First, at step 210, a knock determination process is executed based on the detection signal of knock sensor 34. In the next step 220, it is determined whether or not there is a knock. If it is determined in step 220 that there is a knock, the process proceeds to step 230. In step 230, a fixed value is subtracted from the correction amount akcs of the knock learning value akg (see FIG. 5). If it is determined in step 220 that there is no knock, the process proceeds to step 240. In step 240, a fixed value is added to the correction amount akcs of the knock learning value akg.

In step 250, the retard amount aknk from the basic ignition timing absef is calculated based on Equation 2 (see FIG. 5).
Is calculated.

[0039]

## EQU2 ## Next, in step 260, upper and lower limit guards (0 <aknk <akmax) are set for the retard amount ank, and the routine proceeds to step 270.

In step 270, the final ignition timing aop is calculated on the basis of the equation (3), and the routine proceeds to step 280. The ignition timing of each spark plug 38 is controlled based on the final ignition timing aop calculated in step 270.

[0041]

Aop = absef + aknk In the next step 280, the addition or subtraction of the correction amount akcs in the step 230 or 240 is reflected on the knock learning value akg, and the correction amount akcs is returned to a predetermined value.

As described above, according to the ignition timing control device of the present embodiment, the following effects can be obtained. In the engine 11, the knock limit ignition timing shifts from the basic ignition timing absef to the retard side as the intake air temperature increases or the engine load factor decreases. On the other hand, in the present embodiment, as shown in FIG. 5, based on the map regarding the intake temperature and the engine load and the correction amount of the most retarded ignition timing shown in FIG. The absolute value of the maximum retardation amount akmax is increased by making correction such that the maximum retardation ignition timing akmf decreases as the load factor decreases, and correction is performed such that the maximum retardation ignition timing akmf decreases as the intake air temperature increases. Thus, the correction is made so as to increase the absolute value of the maximum retard amount akmax. for that reason,
With the corrected maximum retard amount akmax, the retard amount does not become insufficient with respect to the knock limit ignition timing according to the intake air temperature and the engine load, and the occurrence of knock can be appropriately suppressed. FIG. 6 shows the effect on the knock limit based on the intake air temperature and the amount of retardation from the basic ignition timing when the engine load factor is set to a predetermined value. The retard amount becomes larger than the sensitivity SEN to the knock limit, and the engine 11
Knocking can be appropriately suppressed.

In the present embodiment, a map relating to the engine load factor and the most retarded ignition timing akmf at the intake temperature α ° C. is held as internal data, and the intake temperature and the engine load factor and the most retarded ignition timing are corrected. Since it is sufficient to hold the map relating to the amount as the internal data, the amount of data is small, and the capacity of the memory of the ECU 40 that stores the amount can be reduced.

The embodiment can be modified and embodied as follows. In the above embodiment, the map relating to the engine load and the most retarded ignition timing akmf at the intake air temperature α ° C.
Load and maximum retarded ignition timing akm at intake temperature β ° C
A map relating to f ′ (see FIG. 5) may be held as internal data, and the correction amount of the most retarded ignition timing may be interpolated from the intake air temperature and the engine load by referring to both maps.

In the above embodiment, the maximum retard amount is corrected by correcting the maximum retard ignition timing.
The maximum retard amount itself may be corrected based on the intake air temperature and the engine load factor.

In the above embodiment, the maximum retardation amount akmf is corrected by correcting the maximum retardation ignition timing akmf based on the intake air temperature as an environmental condition. However, the maximum retardation ignition timing akmf is corrected based on humidity. May be corrected.

In the above embodiment, the ignition timing control device is applied to a gasoline engine as an internal combustion engine. However, the ignition timing control device may be applied to an LPG engine.

[Brief description of the drawings]

FIG. 1 is a schematic sectional view and a block diagram showing an engine according to an embodiment of the present invention.

FIG. 2 is a flowchart illustrating a maximum retard amount calculation process.

FIG. 3 is a flowchart showing an ignition timing calculation process.

FIG. 4 is a map relating to an intake air temperature, an engine load, and a correction amount of a most retarded ignition timing.

FIG. 5 is a graph showing a relationship between an engine load factor and an ignition timing.

FIG. 6 is a graph showing an influence on a knock limit based on an intake air temperature and a retard amount at a predetermined engine load.

[Explanation of symbols]

11: engine as internal combustion engine, 30: intake air temperature sensor, 31: air flow meter, 38: spark plug, 33
... water temperature sensor, 34 ... knock sensor, 35 ... rotation speed sensor, 36 ... igniter, 40 ... ECU.

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Kenji Hashimoto 1 Toyota Town, Toyota City, Aichi Prefecture Inside Toyota Motor Corporation (72) Inventor Kenji Shioya 1-2-28 Goshodori, Hyogo-ku, Kobe City, Hyogo Prefecture Fujitsu Ten Corporation F term (reference) 3G022 DA02 DA04 DA10 EA02 FA05 FA06 GA05 GA06 GA08 GA09 GA11 GA13 GA14

Claims (6)

[Claims] 1. A basic ignition timing calculating means for calculating a basic ignition timing of an internal combustion engine according to an operation state of the engine, and a predetermined amount delayed from a knock limit ignition timing previously obtained according to an operation state of the internal combustion engine. A most retarded ignition timing calculating means for calculating the retarded most retarded ignition timing, and a maximum retardation amount from the basic ignition timing by subtracting the basic ignition timing from the most retarded ignition timing. Retarding amount calculating means, and a knock learning value calculated based on the advance amount from the most retarded ignition timing based on the knock detection of the internal combustion engine is added to the maximum retard amount to thereby determine an operating state. A retard amount calculating means for calculating a retard amount according to: a final ignition timing calculating means for calculating a final ignition timing by adding the retard amount to the basic ignition timing;
An ignition timing control device for an internal combustion engine, comprising: a maximum retardation amount calculating unit that corrects the maximum retardation amount based on an environmental condition and an engine load. 2. An ignition timing control apparatus for an internal combustion engine according to claim 1, wherein said environmental condition is an intake air temperature of the internal combustion engine. 3. The internal combustion engine according to claim 2, wherein said correction means increases the maximum retard amount as the engine load decreases, and increases the maximum retard amount as the intake air temperature increases. Ignition timing control device. 4. The ignition timing control device for an internal combustion engine according to claim 3, wherein said correction means corrects said maximum retardation amount by correcting said maximum retardation ignition timing. 5. The most retarded ignition timing calculating means holds a map relating to the engine load and the most retarded ignition timing at a predetermined intake air temperature as internal data, and refers to the map to determine the engine load from the engine load. The correction means holds a map relating to the intake temperature and the engine load and the correction amount of the maximum retard ignition timing as internal data, and refers to the map to determine the intake temperature and the intake temperature. 5. The ignition timing control device for an internal combustion engine according to claim 4, wherein a correction amount of the most retarded ignition timing is interpolated from the engine load. 6. The most retarded ignition timing calculating means holds a map relating to the engine load and the most retarded ignition timing at a predetermined intake air temperature as internal data, and refers to the map to determine the engine load from the engine load. The most retarded ignition timing is calculated, and the correction means holds a map regarding the engine load and the most retarded ignition timing at the second intake temperature as internal data, and refers to the map to determine the intake temperature and the intake temperature. 5. A method for interpolating a correction amount of a most retarded ignition timing from an engine load.
3. The ignition timing control device for an internal combustion engine according to claim 1.