JP2009002165A - Control device for internal combustion engine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a technology capable of operating an internal combustion engine by appropriate fuel injection and intake air amounts. <P>SOLUTION: A specific crank angle during a rotational speed transition period is set as a reference crank angle. A plurality of crank angles that come after the reference crank angle in order are set as crank angles for determination. Times for each of crank angles to advance from the reference crank angle to each of the crank angles for determination are set as respective crank angle advancement times for determination. Each of times it actually took to advance from the reference crank angle to each of the crank angles for determination during the rotational speed transition period are sequentially calculated as respective crank angle advancement times. A target value of ignition timing is changed only by an amount according to a difference between the actual crank angle advancement time and the crank angle advancement time for determination. The target value of the ignition timing is guarded by an advance guard and a delay guard. When the target value of the ignition timing is on the advance side than the advance guard, or when it is on the delay side than the delay guard, the fuel injection amount or the intake air amount is corrected (S210). <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

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

There is known a technique of storing a history of success or failure of start by a starter motor and changing a fuel injection amount or ignition timing at the start according to the number of start failures (see, for example, Patent Document 1). Further, a technique is known that prohibits the control of the ignition timing to the advance side based on the determination of knocking according to the frequency at which the logarithmic conversion value of the vibration intensity exceeds the upper limit value of the dynamic range (for example, Patent Document 2). reference.).
JP 2003-172174 A JP 2002-188504 A

  By the way, the amount of fuel and intake air supplied to the internal combustion engine may change due to secular change. For example, deposits deposited on the fuel injection valve may cause the fuel injection amount to be smaller than the command value and leaner than the assumed air-fuel ratio. Here, since there is a demand for accurately adjusting the air-fuel ratio to the target value at the time of cold start of the internal combustion engine, more accurate air-fuel ratio control is desired.

  The present invention has been made in view of the above-described problems, and provides a technique capable of operating an internal combustion engine with an appropriate fuel injection amount and intake air amount in a control device for the internal combustion engine. With the goal.

In order to achieve the above object, an internal combustion engine control apparatus according to the present invention employs the following means. That is, the control device for an internal combustion engine according to the present invention provides:
In the control device for an internal combustion engine that controls the ignition timing during the rotational speed transition period from when the internal combustion engine is started until the engine rotational speed changes at a constant rotational speed,
The specific crank angle during the rotational speed transition period is set as a reference crank angle,
A plurality of crank angles that come in order after the reference crank angle during the rotational speed transition period are set as crank angles for determination,
The time taken for the crank angle to advance from the reference crank angle to each judgment crank angle when a fuel having a predetermined property is used is a judgment crank angle advance time,
The time actually taken to travel from the reference crank angle to each judgment crank angle during the rotational speed transition period is sequentially calculated as an actual crank angle progress time, respectively.
The actual crank angle progress time is compared with the corresponding determination crank angle progress time. When the actual crank angle progress time is shorter than the determination crank angle progress time, the actual crank angle progress time and the determination crank angle progress time are The target value of the ignition timing is retarded by an amount corresponding to the difference, and when the actual crank angle progress time is longer than the judgment crank angle progress time, it corresponds to the difference between the actual crank angle progress time and the judgment crank angle progress time. Ignition timing calculation means for advancing the target value of the ignition timing by the amount,
If the ignition timing target value calculated by the ignition timing calculation means is more advanced than the advance guard, which is the advance guard value, the ignition timing target value is changed to an advance guard, or ignition is performed. Ignition timing guard means for changing the target value of the ignition timing to the retard guard when the timing is retarded from the retard guard which is the retard guard value;
The fuel injection amount or the intake air amount is corrected when the target value of the ignition timing calculated by the ignition timing calculation means is on the advance side of the advance guard or on the retard side of the retard guard. Correction means to
It is characterized by providing.

  Here, there are fuels ranging from light to heavy. In general, the lighter the fuel, the higher the volatility and the greater the torque obtained from combustion. Therefore, in order to achieve the required torque, it is necessary to change the ignition timing or the fuel injection amount according to the properties of the fuel.

  The lighter the fuel, the greater the generated torque, and the faster the engine speed increases. Therefore, when a plurality of crank angles that come in order after the reference crank angle during the rotational speed transition period are used as the determination crank angles, the time required to advance from the reference crank angle to each determination crank angle (hereinafter, “ The "crank angle progression time" is shorter when the fuel is light than when it is heavy.

  For example, the crank angle advance time when heavy fuel is used is obtained in advance as the reference crank angle advance time, and if the actual crank angle advance time during the rotational speed transition period is equal to the judgment crank angle advance time, If it is shorter than the determination crank travel time, it can be determined that light fuel is being used.

  The required torque can be obtained by correcting the ignition timing based on such determination.

  Here, if the ignition timing is advanced or retarded too much, the combustion state of the internal combustion engine is adversely affected. Therefore, for example, the advance angle guard and the retard angle guard are set so that the required torque can be obtained. For example, the advance guard and the retard guard may be set so that knocking does not occur and the concentration of HC and CO in the exhaust does not exceed a threshold value. The advance angle guard and the retard angle guard may not be constant. When the target value of the ignition timing calculated by the ignition timing calculating means is between the advance guard and the retard guard, the actual ignition timing is adjusted to the target value. On the other hand, when the calculated target value of the ignition timing is more advanced than the advance guard, the actual ignition timing is adjusted to the advance guard. Further, when the calculated target value of the ignition timing is on the retard side with respect to the retard guard, the actual ignition timing is adjusted to the retard guard.

  As described above, even when the actual ignition timing is set to the advance guard or the retard guard, the ignition timing calculation means calculates the target value of the ignition timing. That is, if the target value of the ignition timing calculated thereafter becomes a value between the advance angle guard and the retard angle guard, the actual ignition timing is set as the target value calculated by the ignition timing calculation means.

  When the number of times that the ignition timing reaches the advance guard or the retard guard is large, it is conceivable that the fuel injection amount or the intake air amount is not appropriate. That is, it is considered that it is difficult to adjust the engine speed to the target value by adjusting the ignition timing. In such a case, by correcting the fuel injection amount or the intake air amount, the fuel injection amount or the intake air amount can be set to an appropriate value, so the number of times that the ignition timing reaches the advance guard or the retard guard. Can be reduced. Thereby, the ignition timing according to the difference between the target engine speed and the actual engine speed can be set.

In the present invention, the target value of the ignition timing calculated by the ignition timing calculating means is the number of times that the advance side is more advanced than the advance side guard, which is the advance side guard value, or the retard side guard value. It further comprises a number of times integration means for integrating the number of times of being retarded from a certain retardation guard,
The correction means corrects the fuel injection amount to be increased when the number of times the advance angle side of the advance angle guard is greater than or equal to the specified number of times in the specified period, and the number of times the delay angle side is more retarded than the delay angle guard is specified. When the specified number of times is exceeded in the period, it is possible to perform correction to reduce the intake air amount.

  It can be considered that the fuel injection amount or the intake air amount is not so appropriate that the advance side or the retard side is more frequent than the advance guard. If the engine speed is low because the output torque of the internal combustion engine is small, the calculated target value of the ignition timing is on the more advanced side than the advanced angle guard. In this case, it can be considered that the air-fuel ratio is leaner than expected. On the other hand, if the correction for increasing the fuel injection amount is performed, the air-fuel ratio can be further lowered, so that the engine speed can be increased. That is, the calculated target value of the ignition timing is less likely to be on the advance side than the advance guard.

  On the other hand, if the engine speed is high due to the large output torque of the internal combustion engine, the calculated target value of the ignition timing is on the retard side with respect to the retard guard. In this case, it can be considered that the amount of air is larger than expected and more fuel is being injected. On the other hand, if the intake air amount is reduced, the fuel injection amount can be reduced, so that an increase in engine speed can be suppressed.

  The specified period is a period necessary for determining whether or not correction of the fuel injection amount or the intake air amount is necessary. For example, it may be set as the number of start times of the internal combustion engine, or may be set as an elapsed time from the start of starting when the internal combustion engine is started once, for example. Further, the specified number of times may be a lower limit value of the number of times that correction of the fuel injection amount or the intake air amount is necessary. Further, the specified number of times may be determined according to the state of exhaust from the internal combustion engine, the startability of the internal combustion engine, and the safety factor. Note that the correction value of the fuel injection amount or the intake air amount may be increased as the integration value by the number integration means increases.

In the present invention, the crank angle corresponding to the advance angle side of the advance angle guard, which is the advance angle side guard value calculated by the ignition timing calculating means, is integrated, or the ignition timing is calculated. The engine further includes an excess accumulation unit that integrates the crank angle corresponding to the retard angle side of the target value of the ignition timing calculated by the timing calculation unit,
The correction means performs correction to increase the fuel injection amount when the crank angle integrated value that is more advanced than the advance guard is equal to or greater than the specified value in the specified period, and is slower than the retard guard. When the integrated value of the crank angle corresponding to the angle side is equal to or more than the specified value in the specified period, it is possible to perform correction for reducing the intake air amount.

  Here, the difference between the calculated ignition timing target value and the retard guard or the advance guard increases as the fuel injection amount or the intake air amount departs from the appropriate value. That is, it can be determined that the larger the integrated value of the difference is, the farther the fuel injection amount or the intake air amount is from the appropriate value. Then, by changing the fuel injection amount or the intake air amount in accordance with the integrated value of the difference, it becomes possible to change the fuel injection amount or the intake air amount according to the degree of deviation from the appropriate value. The specified period is a period necessary for determining whether or not correction of the fuel injection amount or the intake air amount is necessary. For example, it may be set as the number of start times of the internal combustion engine, or may be set as an elapsed time from the start of starting when the internal combustion engine is started once, for example. Further, the specified value may be a lower limit value that requires correction of the fuel injection amount or the intake air amount. Note that the correction value of the fuel injection amount or the intake air amount may be increased as the integrated value obtained by the excess adding means increases.

  According to the present invention, the internal combustion engine can be operated with an appropriate fuel injection amount and intake air amount.

  Hereinafter, specific embodiments of a control device for an internal combustion engine according to the present invention will be described with reference to the drawings.

  FIG. 1 is a diagram illustrating a schematic configuration of an internal combustion engine 1 to which the control device for an internal combustion engine according to the present embodiment is applied, and an intake system and an exhaust system thereof. An internal combustion engine 1 shown in FIG. 1 is a water-cooled four-stroke gasoline engine. A spark plug 12 that generates a spark in the combustion chamber 2 is attached to the internal combustion engine 1.

  An intake passage 3 that leads to the combustion chamber 2 is connected to the internal combustion engine 1. An air flow meter 4 for measuring the intake air amount of the internal combustion engine 1 is attached in the middle of the intake passage 3. A throttle 5 is provided in the intake passage 3 closer to the internal combustion engine 1 than the air flow meter 4.

  A fuel injection valve 6 that injects fuel into the intake passage 3 is attached to the intake passage 3 closer to the internal combustion engine 1 than the throttle 5.

  On the other hand, an exhaust passage 7 leading to the combustion chamber 2 is connected to the internal combustion engine 1.

  The internal combustion engine 1 configured as described above is provided with an ECU 10 that is an electronic control unit for controlling the internal combustion engine 1. The ECU 10 controls the operation state of the internal combustion engine 1 according to the operation conditions of the internal combustion engine 1 and the request of the driver.

  In addition to the above sensors, the ECU 10 outputs an electric signal corresponding to the amount of depression of the accelerator pedal 14 by the driver, and an accelerator opening sensor 15 that can detect the engine load, and a crank position that detects the engine speed. Sensors 11 are connected via electric wiring, and output signals of these various sensors are input to the ECU 10.

  On the other hand, the fuel injection valve 6 and the spark plug 12 are connected to the ECU 10 via electric wiring, and the fuel injection valve 6 and the spark plug 12 are controlled by the ECU 10.

  By the way, as shown in FIG. 2, when the internal combustion engine 1 is started, the engine speed NE settles at a certain speed (so-called idling speed) NEst. Here, if an attempt is made to make the trajectory followed by the engine speed until the engine speed NE settles at a constant speed NEst, the torque to be output from the combustion of the mixture of fuel and air in each cylinder. (Hereinafter referred to as “required torque”) is determined. In the present embodiment, the required torque is set so that the trajectory followed by the engine speed before the engine speed settles to a constant speed becomes a predetermined trajectory. Then, the amount of fuel to be injected from the fuel injection valve 6 (hereinafter referred to as “target fuel injection amount”) is set so that the required torque is achieved.

Fuels range from light to heavy. In general, lighter fuel is more volatile and heavier fuel is less volatile. Therefore, when the same amount of fuel is supplied to the combustion chamber 2 so that the air-fuel ratio of the air-fuel mixture becomes leaner than the stoichiometric air-fuel ratio, and the air-fuel mixture is ignited by the spark plug 12 at the same timing, the lighter the fuel The torque obtained from the combustion of fuel (hereinafter referred to as “output torque”) is large, and the heavier fuel, the smaller the output torque. Therefore, when the target fuel injection amount is set on the assumption that the fuel is light, the required torque cannot be achieved when the fuel actually used is heavy. On the other hand, when the target fuel injection amount is set on the assumption that the fuel is heavy, the required torque cannot be achieved even when the fuel actually used is light. In any case, in order to achieve the required torque, it is necessary to change the target fuel injection amount in accordance with the properties of the fuel.

  However, especially after the start of the internal combustion engine 1 is started (that is, after the cranking of the internal combustion engine 1 is started) until the engine speed settles to a constant speed (hereinafter referred to as “starting period” or “ It is difficult to accurately control the actual fuel injection amount to the target fuel injection amount even if it is attempted to change the fuel injection amount so that the required torque can be achieved during the “rotational speed transition period”. is there. On the other hand, the output torque can also be changed by changing the ignition timing. The ignition timing can be easily changed even during the starting period.

  In this embodiment, therefore, the ignition timing is controlled in accordance with the fuel properties so that the required torque can be achieved during the rotational speed transition period. Next, ignition timing control at this time will be described.

  As described above, when the air-fuel ratio of the air-fuel mixture is leaner than the stoichiometric air-fuel ratio, if the fuel injection amount is the same, the output torque is lighter than when the fuel is heavy. It is bigger in some cases. Therefore, the increase in the engine speed during the speed transition period is faster when the fuel is lighter than when the fuel is heavy. Therefore, when a specific crank angle during the rotational speed transition period is set as a reference crank angle, and a plurality of crank angles that come in order after the reference crank angle during the rotational speed transient operation period are set as crank angles for determination, The time required to travel from the reference crank angle to each judgment crank angle (hereinafter referred to as “crank angle progress time”) is shorter when the fuel is light than when the fuel is heavy. Therefore, for example, the crank angle progression time when heavy fuel is used is obtained in advance as an experiment using the crank angle progression time as the reference crank angle progression time, and the actual crank angle progression time during the rotational speed transition period is determined as the reference crank angle. Heavy fuel is used if it is equal to or approximately equal to the travel time, and light fuel is used if the crank angle travel time calculated during the rotational speed transition period is shorter than the reference crank angle travel time. Will be.

  Therefore, in this embodiment, first, the ignition timing that is the most advanced in the range where knocking does not occur when the heaviest fuel is used is obtained in advance by experiments or the like as the reference ignition timing. Then, a plurality of crank angles that come after the reference crank angle during the rotational speed transition period are selected as judgment crank angles, and when the heaviest fuel is used, the crank angle is deviated from the reference crank angle. The time taken to advance to each determination crank angle is obtained in advance through experiments or the like as the determination crank angle advancement time. When the actual crank angle progression time during the rotational speed transition period is equal to or substantially equal to the corresponding determination crank angle progression time, the ignition timing is set as the reference ignition timing (that is, the ignition timing is not changed). When the actual crank angle progress time during the rotational speed transition period is shorter than the corresponding determination crank angle progress time, the ignition timing is increased by an amount corresponding to the difference between the actual crank angle progress time and the reference crank angle progress time. Is retarded from the reference ignition timing.

  That is, according to this, the determination crank angle that arrives after the reference crank angle is sequentially set as the first determination crank angle, the second determination crank angle, the third determination crank angle (the same applies hereinafter), The time required for the angle to advance from the reference crank angle to the first determination crank angle is defined as the first crank angle advance time, and the time required for the crank angle to advance from the first determination crank angle to the second crank angle is defined as the second time. When the crank angle advancement time is set, and the time taken for the crank angle to advance from the second crank angle to the third crank angle is set as the third crank angle advancement time, first, the first crank angle advancement time and the corresponding determination are made. The crank timing advance time is compared, and the ignition timing is retarded from the reference ignition timing by an amount corresponding to the difference between these times.

Then, the value obtained by adding the second crank angle advance time to the first crank angle advance time is compared with the corresponding crank angle for determination, and the ignition timing is set to the reference ignition by an amount corresponding to the difference between these times. Delayed from time. That is, the difference between the first crank angle progress time and the corresponding determination crank angle progress time is obtained by adding the difference between the second crank angle progress time and the corresponding determination crank angle progress time (hereinafter referred to as “progress”). The ignition timing is retarded from the reference ignition timing by an amount corresponding to “time difference integrated value”). According to this, for example, disturbance or the like affects the calculation of the first crank angle advance time, and the difference between the first crank angle advance time and the corresponding crank angle advance time for determination accurately reflects the properties of the fuel. Even if not, there is no influence of disturbance or the like on the calculation of the next second crank angle advance time, and the difference between the second crank angle advance time and the corresponding determination crank angle advance time accurately determines the fuel properties. If it is reflected, the influence on the integrated time difference is small. Therefore, the ignition timing is set to an optimum ignition timing according to the properties of the fuel.

  Similarly, the value obtained by adding the second crank angle advance time and the third crank angle advance time to the first crank angle advance time is compared with the corresponding crank angle advance time for determination, and according to the difference between these times. The ignition timing is retarded from the reference ignition timing by the amount. In this case, the difference between the first crank angle advance time and the corresponding determination crank angle advance time is different from the difference between the second crank angle advance time and the corresponding determination crank angle advance time and the third crank angle advance. The ignition timing is retarded from the reference ignition timing by an amount corresponding to the value obtained by integrating the time and the difference between the corresponding crank angle advance times (advance time difference integrated values). According to this, even if there is an influence of disturbance or the like on the calculation of the first crank angle advancement time, the influence of the influence on the advancement time difference integrated value is even smaller. Therefore, the optimal ignition timing is set more accurately according to the properties of the fuel.

  Also, the difference between the actual crank angle progress time and the corresponding determination crank angle progress time corresponds to the difference in the properties of the fuel actually used with respect to the heaviest fuel on a one-to-one basis. According to this embodiment, the difference in the properties of the fuel actually used with respect to the heaviest fuel is reflected in the ignition timing control finely.

  In this embodiment, the reference ignition timing and the judgment crank angle advance time are those when the heaviest fuel is used, but when the fuel with a predetermined property is used. May be adopted. In this case, when the lighter fuel than the heaviest fuel is used as the determination crank angle advance time, the actual crank angle advance time becomes longer than the determination crank angle advance time. It can happen. In this case, the ignition timing is advanced from the reference ignition timing by an amount corresponding to the difference between the actual crank angle advance time and the determination crank angle advance time.

  Further, in this embodiment, when the actual crank angle advance time is first calculated, the difference between the crank angle advance time and the corresponding determination crank angle advance time is reflected in the retard of the ignition timing. However, not when the actual crank angle advance time is calculated for the first time, but when the actual crank angle advance time is calculated a predetermined number of times, the crank angle advance time and the corresponding determination crank angle advance time The difference may be reflected in the retard of the ignition timing.

  In this embodiment, the ignition timing that is the most advanced in the range where knocking does not occur when the heaviest fuel is used is used as the reference ignition timing. According to this, when the heaviest fuel is used, the required torque can be achieved with the smallest amount of fuel. However, the amount of fuel required to achieve the required torque is slightly larger, but slightly retarded from the most advanced ignition timing in the range where knocking does not occur when the heaviest fuel is used. The ignition timing on the side may be used as the reference ignition timing. This is advantageous when the fuel actually used is heavier than the fuel he thought was the heaviest fuel.

  In other words, if the fuel actually used was heavier than the fuel that was considered the heaviest fuel, the fuel actually used would be the heaviest fuel. If the required torque is to be achieved with the same amount of fuel as that of the fresh fuel, the ignition timing must be advanced from the reference ignition timing. However, if the reference ignition timing is the most advanced ignition timing within the range where knocking does not occur, knocking may occur if the ignition timing is advanced from the reference ignition timing. . However, if the ignition timing slightly retarded from the most advanced ignition timing is used as the reference ignition timing within the range where knocking does not occur when the heaviest fuel is used, knocking will occur. In other words, the ignition timing can be retarded from the reference ignition timing. In this case, in order to achieve the required torque, the target ignition timing is set to the target ignition timing as compared with the case where the ignition timing that is most retarded in the range where knocking does not occur when the heaviest fuel is used. The fuel injection amount is set slightly larger.

  In this embodiment, a four-cylinder internal combustion engine is described. However, the present invention is also applicable to an internal combustion engine having a plurality of other cylinders. In the present embodiment, the internal combustion engine provided with the fuel injection valve so as to inject fuel into the intake port is described. However, the fuel injection valve is provided so as to inject fuel directly into the combustion chamber 2. It can also be applied to an internal combustion engine.

  Next, a specific example of ignition timing control will be described. In the internal combustion engine 1 according to the present embodiment, in each cylinder, four strokes of an intake stroke, a compression stroke, an expansion stroke, and an exhaust stroke are executed as one cycle. When the four cylinders are referred to as the first cylinder, the second cylinder, the third cylinder, and the fourth cylinder, respectively, the cycle of each cylinder is the same as that of the first cylinder, the third cylinder, the fourth cylinder, and the second cylinder. The crank angle is shifted by 180 ° in order. One cycle is completed at a crank angle of 720 °.

  Here, for example, when the cycle in which the air-fuel mixture burns first during the rotational speed transition period is the cycle executed in the first cylinder, the compression top dead center in the compression stroke of the cycle in which the air-fuel mixture burns first is calculated. The reference crank angle is set, and the compression top dead center in the compression stroke of the third cylinder performed immediately after the compression stroke of the first cylinder is set as the first crank angle, and the crank angle advances from the reference crank angle to the first crank angle. The calculated time is calculated as the first crank angle progress time.

  Further, the time taken for the crank angle to advance from the first crank angle to the second crank angle, with the compression top dead center in the compression stroke of the fourth cylinder performed immediately after the compression stroke of the third cylinder as the second crank angle. Is calculated as the second crank angle progression time. Furthermore, the compression top dead center in the compression stroke of the second cylinder performed immediately after the compression stroke of the fourth cylinder is defined as the third crank angle, and the time taken for the crank angle to advance from the second crank angle to the third crank angle. Is calculated as the third crank angle progression time. Furthermore, the compression top dead center in the compression stroke of the first cylinder performed immediately after the compression stroke of the second cylinder is the fourth crank angle, and the time taken for the crank angle to advance from the third crank angle to the fourth crank angle Is calculated as the fourth crank angle progression time. Similarly, the fifth crank angle progress time is calculated.

  A value obtained by integrating the first crank angle advance time to the fifth crank angle advance time is defined as the crank angle advance time integrated value.

Then, a value obtained by integrating the first crank angle advance time to the fifth crank angle advance time when the heaviest fuel is used is obtained in advance by an experiment or the like as a determination crank angle advance time integrated value. Furthermore, when the heaviest fuel is used, when the fuel of the target fuel injection amount is injected from the fuel injection valve, the ignition timing capable of achieving the required torque is set as the reference ignition timing through experiments or the like in advance. I ask for it. Then, the actual crank angle progress time integrated value is compared with the corresponding determination crank angle progress time integrated value, and the actual crank angle progress time integrated value is smaller than the corresponding determination crank angle progress time integrated value. Sometimes, the ignition timing is retarded from the reference ignition timing by an amount corresponding to the difference between these integrated values. On the other hand, when the actual crank angle advance time integrated value is larger than the corresponding determination crank angle advance time integrated value, the ignition timing is advanced from the reference ignition timing by an amount corresponding to the difference between these integrated values. When the actual crank angle progress time integrated value is equal to or substantially equal to the corresponding determination crank angle progress time integrated value, the ignition timing is set as the reference ignition timing.

  In this embodiment, the reference crank angle is the crank angle in the cycle in which the air-fuel mixture is first combusted during the rotational speed transition period, but the crank angle before the air-fuel mixture is first combusted can also be used as the reference crank angle. Good.

  Next, this ignition timing control will be described with reference to FIG. In FIG. 3, 0 indicates the time when the crank angle is at the reference crank angle, T1 to T5 indicate the time when the crank angle is at the first determination crank angle after the reference crank angle, and the second determination crank. The time at the angle, the time at the third determination crank angle, the time at the fourth determination crank angle, and the time at the fifth determination crank angle are shown.

  In FIG. 3, PX1 to PX5 indicate the time required for the crank angle to advance from the reference crank angle to the first determination crank angle when the heaviest fuel is used (hereinafter referred to as “first "Crank angle progress time for determination")) Time required to advance to the second determination crank angle (hereinafter referred to as "second determination crank angle progress time"), third determination crank angle (Hereinafter referred to as “third determination crank angle progress time”) and time required to proceed to the fourth determination crank angle (hereinafter referred to as “fourth determination crank angle progress time”). The time taken to advance to the fifth determination crank angle (hereinafter referred to as “fifth determination crank angle advancement time”) is shown.

  On the other hand, in FIG. 3, PY1 to PY5 are the time taken for the crank angle to actually advance from the reference crank angle to the first determination crank angle (hereinafter referred to as “first crank angle advancement time”). Time taken to advance to the second judgment crank angle (hereinafter referred to as “second crank angle advancement time”) Time taken to advance to the third judgment crank angle (hereinafter referred to as “ 3rd crank angle advancement time)) Time taken to advance to the 4th determination crank angle (hereinafter referred to as "4th crank angle advancement time") Up to the 5th determination crank angle It shows the time taken to travel (hereinafter referred to as “fifth crank angle progression time”).

  According to the present embodiment, when the first crank angle advance time PY1 is calculated, this is compared with the first determination crank angle advance time PX1. Here, as shown in FIG. 3, when the time PY1 is shorter than the time PX1 and there is a time difference D1 between these times, the ignition timing is retarded from the reference ignition timing by an amount corresponding to the time difference D1. . Further, when the second crank angle advance time PY2 is calculated, it is compared with the second determination crank angle advance time PX2. Here, as shown in FIG. 3, when the time PY2 is shorter than the time PX2 and there is a time difference D2 between these times, the ignition timing is retarded from the reference ignition timing by an amount corresponding to the time difference D2. .

Further, when the third crank angle advance time PY3 is calculated, the ignition timing is retarded from the reference ignition timing by an amount corresponding to the time difference D3 between this and the third determination crank angle advance time PX3. When the fourth crank angle advance time PY4 is calculated, the ignition timing is retarded from the reference ignition timing by an amount corresponding to the time difference D4 between this and the fourth determination crank angle advance time PX4. Further, when the fifth crank angle advance time PY5 is calculated, the ignition timing is retarded from the reference ignition timing by an amount corresponding to the time difference D5 between this and the fifth determination crank angle advance time PX5.

  Here, in the example shown in FIG. 3, since the time difference D1 increases in order from the time difference D1, the ignition timing corresponds to the time difference D2 rather than the case where the ignition timing is retarded from the reference ignition timing by an amount corresponding to the time difference D1. When retarded from the reference ignition timing by that amount, the retarded angle is greatly retarded. Similarly, the amount of retardation increases in the order of time difference D3, time difference D4, and time difference D5.

  That is, an example of the ignition timing control described with reference to FIG. 3 is as follows when described with reference to FIG. In FIG. 4, PZ1 is the time taken for the crank angle to actually travel from the reference crank angle to the first determination crank angle T1 (hereinafter referred to as “first crank angle advancement time”), PZ2. Is the time taken for the crank angle to actually travel from the first determination crank angle T1 to the second determination crank angle T2 (hereinafter referred to as “second crank angle advancement time”), and PZ3 is PZ4 is actually the time taken for the crank angle to travel from the second determination crank angle T2 to the third determination crank angle T3 (hereinafter referred to as “the third crank angle advancement time”). The time taken for the crank angle to travel from the third determination crank angle T3 to the fourth determination crank angle T4 (hereinafter referred to as “fourth crank angle advancement time”). , PZ5 is the time taken for the crank angle to actually travel from the fourth determination crank angle T4 to the fifth determination crank angle T5 (hereinafter referred to as “fifth crank angle advancement time”). Say.

  That is, according to the present embodiment, when the first crank angle advance time PZ1 (this corresponds to the first crank angle advance time PY1 shown in FIG. 3) is calculated, this and the first determination crank. The angle progression time PX1 is compared. Here, as shown in FIG. 4, when the time PZ1 is shorter than the time PX1 and there is a time difference D1 between these times, the ignition timing is retarded from the reference ignition timing by an amount corresponding to the time difference D1. . Further, when the second crank angle advance time PZ2 is calculated, this is added to the first crank angle advance time PZ1, and the first integrated value (this is the second crank angle advance time PY2 shown in FIG. 3). And the first integrated value is compared with the second determination crank angle advance time PX2. Here, as shown in FIG. 4, when the first integrated value (PZ1 + PZ2) is shorter than the time PX2 and there is a time difference D2 between these times, the ignition timing is the reference ignition timing corresponding to the time difference D2. Is delayed.

  Further, when the third crank angle advance time PZ3 is calculated, it is added to the first integrated value (PZ1 + PZ2) to obtain a second integrated value (this is the third crank angle advance time PX3 shown in FIG. 3). The second integrated value is compared with the third determination crank angle travel time PX3. Here, as shown in FIG. 4, when the second integrated value (PZ1 + PZ2 + PZ3) is shorter than the time PX3 and there is a time difference D3 between these times, the ignition timing is the reference ignition timing corresponding to the time difference D3. Is delayed. Further, when the fourth crank angle advance time PZ4 is calculated, it is added to the second integrated value (PZ1 + PZ2 + PZ3) to obtain a third integrated value (this is the fourth crank angle advance time PX4 shown in FIG. 3). And the third integrated value is compared with the fourth determination crank angle travel time PX4. Here, as shown in FIG. 4, when the third integrated value (PZ1 + PZ2 + PZ3 + PZ4) is shorter than the time PX4 and there is a time difference D4 between these times, the ignition timing is determined by the amount corresponding to the time difference D4. Delayed from ignition timing.

Further, when the fifth crank angle advance time PZ5 is calculated, it is added to the third integrated value (PZ1 + PZ2 + PZ3 + PZ4) to obtain a fourth integrated value (this is the fifth crank angle advance time PX5 shown in FIG. 3). And the fourth integrated value is compared with the fifth determination crank angle travel time PX5. Here, as shown in FIG. 4, when the fourth integrated value (PZ1 + PZ2 + PZ3 + PZ4 + PZ5) is shorter than the time PX5 and there is a time difference D5 between these times, the ignition timing is determined by the amount corresponding to the time difference D5. Delayed from ignition timing.

  According to the ignition timing control according to the present embodiment, the heavier the fuel used, the more the ignition timing is set to the advance side, so that the combustion becomes stable. Further, the heavier the fuel used, the higher the combustion efficiency when the ignition timing is set to the advance side. For this reason, if the fuel injection amount is the same, the output torque increases as the combustion efficiency increases, so that the operating state of the internal combustion engine 1 can be quickly stabilized after the internal combustion engine 1 is started. On the other hand, since the required torque can be achieved even if the fuel injection amount is reduced, the required torque can be achieved and the fuel efficiency can be improved when the fuel injection amount is reduced, as the combustion efficiency increases. Can be made.

  Further, the lighter the fuel used, the higher the combustion efficiency, and the required torque can be achieved with less fuel. In other words, if the fuel injection valve is injected with an amount of fuel that can achieve the required torque when the fuel used is the heaviest, even though the fuel used is light, a torque that exceeds the required torque is generated. End up. However, according to the ignition timing control according to the present embodiment, the lighter the fuel used, the retarded the ignition timing, so that the energy that becomes the torque for driving the internal combustion engine 1 is reduced. Therefore, if the retard amount of the ignition timing is set to an appropriate amount, the required torque can be achieved.

  Furthermore, if the ignition timing is retarded as the fuel used is lighter, the energy that does not become the torque that drives the internal combustion engine 1 becomes thermal energy, so that the temperature of the exhaust gas rises. Therefore, when an exhaust purification device such as a three-way catalyst is disposed in the exhaust passage, the temperature of the exhaust purification catalyst can be quickly raised to the activation temperature. Therefore, it is possible to reduce the discharge amount of harmful substances.

  Further, according to the ignition timing control according to the present embodiment, if the fuel used is light, the ignition timing is sequentially retarded for each cylinder. That is, in each cylinder, an appropriate ignition timing is set for achieving the required torque and reducing the discharge amount of harmful substances. Therefore, even if the fuel injection amount for each cylinder is the same, the required torque can be achieved and the emission amount of harmful substances can be reduced.

  If the ignition timing is retarded, knocking may occur in the combustion chamber 2. Therefore, the ignition timing at which knocking may occur or the ignition timing at which knocking may occur is retarded. It is good also as a limit when doing. Further, if the ignition timing is retarded too much, the amount of energy that is not consumed by the torque that drives the internal combustion engine 1 increases, so that the ignition timing that does not consume all of the energy by the torque that drives the internal combustion engine 1 is used as the reference ignition. It is good also as a limit when retarding a time.

  FIG. 5 is a flowchart showing a flow of ignition timing control according to the present embodiment. In the routine of FIG. 5, in step S101, it is determined whether or not the number of times of ignition Nsa to the air-fuel mixture executed after the air-fuel mixture is first combusted is equal to or less than the predetermined number Nsath. Here, when it is determined that Nsa> Nsath, this routine ends as it is. On the other hand, when it is determined that Nsa ≦ Nsath, the process proceeds to step S102.

In step S102, a difference Td between the time taken for the crank angle to advance from the reference crank angle to the third determination crank angle and the corresponding determination crank angle advance time is calculated. That is, when the time taken for the crank angle to travel from the reference crank angle to the third determination crank angle is “T3” and the corresponding determination crank angle progress time is “RT3”, these times The difference Td is calculated according to the equation Td = RT3−T3.

  Next, in step S103, the ignition timing TSA is calculated based on the difference Td calculated in step S102. That is, when the ignition timing is “TSAbase” and the retarding coefficient serving as a reference for retarding the reference ignition timing is “K”, the ignition timing TSA is calculated according to the equation TSA = TSAbase + Td × K. . In this embodiment, the ECU 10 that processes step S103 corresponds to the ignition timing calculation means in the present invention.

  Next, in step S104, the ignition timing TSA calculated in step S103 is behind the ignition timing at which knocking occurs, and the ignition timing is such that all of the energy is not consumed by the torque driving the internal combustion engine 1. The ignition timing TSA is guarded so as to be on the advance side. Here, the ignition timing at the most retarded side among the ignition timings at which knocking occurs is hereinafter referred to as “advance angle guard”, and is the most among the ignition timings in which all of the energy is not consumed by the torque driving the internal combustion engine 1. Hereinafter, the ignition timing on the advance side is referred to as “retard guard”. That is, the actual ignition timing is between the advance guard and the retard guard. In this embodiment, the ECU 10 that processes step S104 corresponds to the ignition timing guard means in the present invention.

  The ignition timing calculated by the current routine is reflected in the fifth ignition with the ignition that first burns the air-fuel mixture as the first ignition. Then, the routine of FIG. 5 continues to calculate the ignition timing unless it is determined in step S101 that Nsa> Nsath. Accordingly, when it is determined in step S101 that Nsa ≦ Nsath is next executed when the routine of FIG. 5 is executed, the crank angle advances from the reference crank angle to the fourth determination crank angle in step S102. A difference Td between the time taken and the corresponding crank angle progression time is calculated.

  Next, in step S103, the ignition timing TSA is calculated based on the difference Td. In step S104, the ignition timing TSA is guarded. The ignition timing calculated by this routine is reflected in the sixth ignition timing. Thereafter, similarly, the routine of FIG. 5 continues to calculate the ignition timing until it is determined in step S101 that Nsa> Nsath.

  The retardation coefficient K used in the above-described routine may be a constant value, but may be a value that varies based on various conditions. For example, when the temperature in the cylinder is high, the air-fuel mixture is easily combusted, so that the output torque increases even if the ignition timing is the same. That is, if the temperature in the cylinder is high, the required torque can be achieved even if the ignition timing is retarded. Therefore, the retardation coefficient K used in the routine described above may be a value that increases as the temperature in the cylinder increases.

  In the above-described embodiment, the time taken for the crank angle to advance from the reference crank angle to the predetermined crank angle is adopted as the fuel property determination parameter. However, the engine speed and the angular acceleration of the crankshaft are determined as the fuel property determination parameter. It may be adopted as a parameter. Here, when the engine speed is adopted as the fuel property parameter, for example, the engine speed at the reference crank angle and the engine speed at a predetermined crank angle when the heaviest fuel is used. The difference is determined in advance as an engine speed difference for determination through experiments, and the difference between the engine speed at the reference crank angle and the engine speed at the predetermined crank angle is calculated as the engine speed difference during the engine speed transition period. When the rotational speed difference is larger than the determination rotational speed difference, the ignition timing is retarded from the reference ignition timing by an amount corresponding to the difference between the rotational speed difference and the determination rotational speed difference. Of course, when the above-described rotational speed difference is equal to or substantially equal to the determination rotational speed difference, the ignition timing is set as the reference ignition timing.

  Further, when the angular acceleration of the crankshaft is adopted as the fuel property parameter, for example, the angular acceleration at the first crank angle is added to the angular acceleration at the reference crank angle when the heaviest fuel is used. The obtained value is obtained in advance by experiments or the like as the reference angular acceleration integrated value. Then, during the rotational speed transition period, the angular acceleration at the first crank angle is added to the angular acceleration at the reference crank angle, and this is used as the angular acceleration integrated value. When the angular acceleration integrated value is equal to the reference integrated value, it is determined that the fuel is heavy. When the angular acceleration integrated value is larger than the reference angular acceleration integrated value, the angular acceleration integrated value and the reference angular acceleration are determined. The ignition timing is retarded from the reference ignition timing by an amount corresponding to the difference from the integrated value. Of course, when the angular acceleration integrated value is equal to or substantially equal to the reference angular acceleration integrated value, the ignition timing is set as the reference ignition timing.

  In this embodiment, the reference crank angle and the first crank angle are used as the compression top dead center of the compression stroke in each cylinder. However, if the corresponding crank angle is used in each cylinder, for example, the expansion bottom dead center or the exhaust top dead center. A crank angle such as a point may be used. That is, in this embodiment, the reference crank angle and the first crank angle are set to the predetermined crank angle corresponding to each cylinder.

  In this embodiment, the ignition timing is controlled, but instead, the fuel injection amount may be controlled. Further, the ignition timing and the fuel injection amount may be controlled. When controlling the fuel injection amount, for example, when the actual crank angle advance time is shorter than the determination crank angle advance time, the fuel injection amount is decreased by an amount corresponding to the difference between these times, and the actual crank angle When the advance time is longer than the determination crank angle advance time, the fuel injection amount is increased by an amount corresponding to the difference between these times. Further, when controlling the ignition timing and the fuel injection amount, for example, when the actual crank angle advance time is shorter than the determination crank angle advance time, the ignition timing is retarded by an amount corresponding to the difference between these times. In addition, when the fuel injection amount is reduced and the actual crank angle advance time is longer than the determination crank angle advance time, the ignition timing is advanced by an amount corresponding to the difference between these times, and the fuel injection amount is increased. To do.

  In this embodiment, when the calculated ignition timing TSA is more advanced than the advance guard, the correction is made to increase the fuel injection amount and the retard is slower than the retard guard. If the number of corners is more than the specified number, correction is performed to reduce the intake air amount.

  Here, for example, in an operation region where the change in the output torque becomes large with respect to the change in the air-fuel ratio in the combustion chamber 2, it is easy to determine whether or not the air-fuel ratio in the combustion chamber 2 is appropriate. For example, when the calculated ignition timing TSA is on the advance side with respect to the advance guard, it is considered that the output speed is insufficient and the engine speed is reduced. That is, it is considered that the air-fuel ratio is lean. For example, if deposits adhere to the fuel injection valve 6, the fuel injection amount per unit time from the fuel injection valve 6 will be smaller than when it is new. That is, the fuel injection amount decreases with respect to the command value from the ECU 10, and the air-fuel ratio becomes lean. On the other hand, if the command value from the ECU 10 is changed so that more fuel is injected from the fuel injection valve 6, the actual fuel injection amount becomes an appropriate value. Can be controlled. At this time, the intake air amount may be constant.

  On the other hand, for example, when the calculated ignition timing TSA is on the retard side with respect to the retard guard, for example, the intake air amount is increased and the fuel injection amount is considered to be increased accordingly. . That is, it is considered that as the intake air amount increases, the output torque increases and the engine speed increases. On the other hand, since the fuel injection amount can be reduced by reducing the intake air amount, an increase in output torque can be suppressed. For example, the amount of intake air can be reduced by turning the throttle 5 to the closed side. At this time, the intake air amount and the fuel injection amount may be decreased so that the air-fuel ratio becomes constant.

  Here, FIG. 6 shows the fuel injection amount or the intake air amount in accordance with the number of times the calculated ignition timing TSA is advanced from the advance guard or the retard from the retard guard. It is the flowchart which showed the flow which changes. This routine is executed in conjunction with the routine shown in FIG.

  In step S201, the routine shown in FIG. 5 is executed.

  In step S202, it is determined whether the internal combustion engine 1 has been normally started. Here, when the internal combustion engine 1 is not normally started, it is difficult to determine what is causing the abnormality, so only when the internal combustion engine 1 is normally started. The fuel injection amount or the intake air amount is changed.

  If an affirmative determination is made in step S202, the process proceeds to step S203. On the other hand, if a negative determination is made, the correction amount is reset in step S204, and the process returns to step S201. This correction amount is a correction amount for the fuel injection amount or the intake air amount.

  In step S203, it is determined whether or not the calculated ignition timing TSA is ahead of the advance guard. That is, it is determined whether or not the calculated ignition timing TSA reaches the advance guard and the actual ignition timing is equal to the advance guard. If an affirmative determination is made in step S203, the process proceeds to step S205, and if a negative determination is made, the process proceeds to step S206.

  In step S205, the advance angle memory is counted up. This advance memory counts the number of times that the calculated ignition timing TSA has advanced from the advance guard.

  In step S206, it is determined whether or not the calculated ignition timing TSA is behind the retard guard. That is, it is determined whether or not the calculated ignition timing TSA reaches the retard guard and the actual ignition timing is equal to the retard guard. If an affirmative determination is made in step S206, the process proceeds to step S207, and if a negative determination is made, the process proceeds to step S208.

  In step S207, the retard memory is counted up. This retard memory counts the number of times that the calculated ignition timing TSA is retarded from the retard guard.

  In the present embodiment, the ECU 10 that processes step S205 or step S207 corresponds to the number accumulation means in the present invention.

  In step S208, it is determined whether the number of trips has reached a predetermined value or more. The number of trips is the number of times past the rotational speed transition period. Moreover, it is good also as the frequency | count that the internal combustion engine 1 started. Furthermore, the number of times the routine shown in FIG. 5 is executed in one start of the internal combustion engine 1 may be used. The predetermined value is the number of trips necessary for determining whether or not the fuel injection amount or the intake air amount needs to be corrected. That is, in this step, it is determined whether or not a period enough to determine whether correction of the fuel injection amount or the intake air amount is necessary has elapsed. If an affirmative determination is made in step S208, the process proceeds to step S209, and if a negative determination is made, the process proceeds to step S212.

In step S209, it is determined whether or not the advance memory calculated in step S205 or the retard memory calculated in step S207 is within a specified range (that is, a threshold value or less). This threshold value is obtained in advance by experiments or the like as a value that requires correction of the fuel injection amount or the intake air amount. The threshold value may be set to different values for the advance angle memory and the retard angle memory. If an affirmative determination is made in step S209, the process proceeds to step S211. If a negative determination is made, the process proceeds to step S210.

  In step S210, the fuel injection amount or the intake air amount is corrected. That is, if the advance angle memory is equal to or greater than the threshold value, the fuel injection amount is increased, and if the retard angle memory is equal to or greater than the threshold value, the intake air amount is decreased. The correction value may be a prescribed value, and may be changed according to the number of times stored in the advance angle memory or the retard angle memory. That is, the correction value may be increased as the number of times increases. In this embodiment, the ECU 10 that processes step S210 corresponds to the correcting means in the present invention.

  In step S211, the advance angle memory, the retard angle memory, and the number of trips are reset. That is, all are set to 0.

  In step S212, the number of trips is counted up.

  In this way, since the fuel injection amount or the intake air amount can be corrected, the internal combustion engine can be controlled more appropriately.

  In this embodiment, when the calculated ignition timing TSA is on the advance side with respect to the advance guard, the extent to which the advance guard is exceeded is integrated, or the retard side is on the retard side with respect to the retard guard. When it becomes, it is accumulated how much it exceeds the retard guard. Then, the fuel injection amount or the intake air amount is corrected according to each integrated value. Since other hardware is the same as that of the first embodiment, description thereof is omitted.

  FIG. 7 is a flowchart showing a flow for changing the fuel injection amount or the intake air amount according to this embodiment. Note that portions different from the routine shown in FIG. 6 will be mainly described.

  In step S301, the difference between the advance guard and the calculated ignition timing TSA is integrated. That is, the crank angle corresponding to the calculated ignition timing TSA exceeding the advance guard is integrated.

  In step S302, the difference between the calculated ignition timing TSA and the retard guard is integrated. That is, the crank angle corresponding to the calculated ignition timing TSA exceeding the retard guard is integrated.

  In this embodiment, the ECU 10 that processes step S301 or step S302 corresponds to the excess accumulation means in the present invention.

  In step S303, it is determined whether or not the integrated value calculated in step S301 or the integrated value calculated in step S302 is within a specified range (that is, a threshold value or less). This threshold value is obtained in advance by experiments or the like as a value that requires correction of the fuel injection amount or intake air amount. The threshold value may be set to a different value for the advance value on the advance side and the integrated value on the retard side. If an affirmative determination is made in step S303, the process proceeds to step S305, and if a negative determination is made, the process proceeds to step S304.

In step S304, the fuel injection amount or the intake air amount is corrected. That is, the fuel injection amount is increased if the integrated value on the advance side is equal to or greater than the threshold value, and the intake air amount is decreased if the integrated value on the retard side is equal to or greater than the threshold value. The correction value may be a fixed value, or may be increased according to the size of each integrated value.

  In step S305, the advance value, the retard value, and the number of trips are reset. That is, all are set to 0. In this embodiment, the ECU 10 that processes step S305 corresponds to the correcting means in the present invention.

  In this way, the fuel injection amount or the intake air amount can be corrected according to the value at which the calculated ignition timing TSA exceeds the advance guard or retard guard, so that the internal combustion engine is controlled more appropriately. be able to.

1 is a diagram illustrating a schematic configuration of an internal combustion engine to which an internal combustion engine control device according to an embodiment is applied, and an intake system and an exhaust system thereof. FIG. It is a figure which shows transition of the engine speed at the time of engine starting. It is a figure which shows the time taken for a crank angle to advance from a reference | standard crank angle to each predetermined crank angle. It is a figure which shows the time taken for a crank angle to advance from a reference | standard crank angle to each predetermined crank angle. It is the flowchart which showed the flow of ignition timing control. A flow of changing the fuel injection amount or the intake air amount in accordance with the number of times the calculated ignition timing TSA is advanced from the advance guard or from the retard guard is shown. It is a flowchart. 6 is a flowchart illustrating a flow for changing a fuel injection amount or an intake air amount according to a second embodiment.

Explanation of symbols

1 Internal combustion engine 2 Combustion chamber 3 Intake passage 4 Air flow meter 5 Throttle 6 Fuel injection valve 7 Exhaust passage 10 ECU
11 Crank position sensor 12 Spark plug 14 Accelerator pedal 15 Accelerator opening sensor

Claims (3)

In a control device for an internal combustion engine that controls ignition timing during a rotational speed transition period from when the internal combustion engine is started until the engine rotational speed changes at a constant rotational speed,
The specific crank angle during the rotational speed transition period is set as a reference crank angle,
A plurality of crank angles that come in order after the reference crank angle during the rotational speed transition period are set as crank angles for determination,
The time taken for the crank angle to advance from the reference crank angle to each judgment crank angle when a fuel having a predetermined property is used is referred to as a judgment crank angle progress time,
The time actually taken to travel from the reference crank angle to each judgment crank angle during the rotational speed transition period is sequentially calculated as an actual crank angle progress time, respectively.
The actual crank angle progress time is compared with the corresponding determination crank angle progress time. When the actual crank angle progress time is shorter than the determination crank angle progress time, the actual crank angle progress time and the determination crank angle progress time are The target value of the ignition timing is retarded by an amount corresponding to the difference, and when the actual crank angle progress time is longer than the judgment crank angle progress time, it corresponds to the difference between the actual crank angle progress time and the judgment crank angle progress time. Ignition timing calculation means for advancing the target value of the ignition timing by the amount,
If the ignition timing target value calculated by the ignition timing calculation means is more advanced than the advance guard, which is the advance guard value, the ignition timing target value is changed to an advance guard, or ignition is performed. Ignition timing guard means for changing the target value of the ignition timing to the retard guard when the timing is retarded from the retard guard which is the retard guard value;
The fuel injection amount or the intake air amount is corrected when the target value of the ignition timing calculated by the ignition timing calculation means is on the advance side of the advance guard or on the retard side of the retard guard. Correction means to
A control device for an internal combustion engine, comprising: The number of times the target value of the ignition timing calculated by the ignition timing calculation means is advanced from the advance guard, which is the advance guard value, or later than the retard guard, which is the retard guard value. It further includes a number-of-times integrating means for integrating the number of times on the corner side,
The correction means corrects the fuel injection amount to be increased when the number of times the advance angle side of the advance angle guard is greater than or equal to the specified number of times in the specified period, and the number of times the delay angle side is more retarded than the delay angle guard is specified. 2. The control apparatus for an internal combustion engine according to claim 1, wherein the correction is performed so that the intake air amount is reduced when the number of times is equal to or more than the prescribed number. The crank angle corresponding to the advance angle side of the advance angle guard, which is the advance angle side guard value calculated by the ignition timing calculation means, is integrated or calculated by the ignition timing calculation means. Further includes an excess accumulating means for accumulating the crank angle corresponding to the retarded ignition timing target value from the retard guard,
The correction means performs correction to increase the fuel injection amount when the crank angle integrated value that is more advanced than the advance guard is equal to or greater than the specified value in the specified period, and is slower than the retard guard. 2. The control apparatus for an internal combustion engine according to claim 1, wherein when the integrated value of the crank angle corresponding to the angle side is equal to or greater than a specified value in a specified period, correction is performed to reduce the intake air amount.

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