JP3460942B2 - Control device for internal combustion engine - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a control device for an internal combustion engine that discharges exhaust gas via a purifying device.

[0002]

2. Description of the Related Art Generally, in an internal combustion engine equipped with a catalyst device such as a three-way catalyst, the required purification performance of exhaust gas is ensured unless the temperature of the catalyst device rises to some extent and the catalyst device is activated. Difficult to do. For this reason, securing the exhaust gas purification performance immediately after the start of the internal combustion engine in which the temperature of the catalyst device is relatively low has become a more important issue than in the past.

Techniques for solving such problems are
The applicant of the present application has proposed in Japanese Patent Application No. 9-109197, and this is the following technique.

That is, in the idling operation after the internal combustion engine is started, the intake air amount of the internal combustion engine is increased as compared with the normal idling operation (for example, the idling operation after the running of the vehicle equipped with the internal combustion engine). Further, after the intake air amount is started to be increased, the rotation speed (actual rotation speed) of the internal combustion engine, which tends to increase due to this increase, is converged to the required target rotation speed for the idling operation immediately after the internal combustion engine is started. A command value for the ignition timing of the internal combustion engine is generated by feedback control processing. Then, by controlling the actual ignition timing of the internal combustion engine based on the generated command value of the ignition timing, the ignition timing of the internal combustion engine is corrected and controlled so as to be retarded as compared with the normal case.

By performing such an increase control of the intake air amount of the internal combustion engine and a control of retarding the ignition timing, the combustion heat generation amount of the internal combustion engine increases and the temperature of the exhaust gas rises, As a result, the catalyst device heated by the exhaust gas is activated early. As a result, the required purification performance of the catalyst device can be secured at an early stage after the start of the internal combustion engine.

Further, in the above-mentioned technique, the engine speed, which tends to rise as a result of the increase in the intake air amount of the engine, is feedback-controlled to the target engine speed, and as a result, the ignition timing is retarded. Therefore, the intake air amount increase control and the ignition timing control can be performed independently of each other, and the control system thereof can be simplified.

By the way, the ignition timing of the internal combustion engine has a permissible range in which the ignition timing can be actually manipulated due to the mechanical or electrical characteristics of an ignition device such as a distributor and the operating characteristics of the internal combustion engine. However, at an ignition timing that deviates from this allowable range, stable operation of the internal combustion engine cannot be ensured.

Therefore, even in the technique of controlling the ignition timing to the retard side as described above, the command value of the ignition timing generated by the above-mentioned feedback control processing (this is how in the calculation processing of the feedback control. However, the actual ignition timing of the internal combustion engine is forcibly set to the retard side limit value. I try to limit it.

On the other hand, the friction (friction) of each part of the internal combustion engine decreases as it warms up. Therefore, after a certain amount of time elapses after the internal combustion engine is started, the rotational speed of the internal combustion engine is constant at the intake air amount. Then, the engine speed tends to increase with respect to the target engine speed. For this reason, the command value of the ignition timing generated by the above-described feedback control process is likely to be on the retard side of the retard side limit value.

However, in such a state that the command value of the ignition timing generated by the feedback control exceeds the retard side limit value, as described above, the actual ignition timing of the internal combustion engine is changed to the retard side limit value. Therefore, the actual ignition timing is on the advance side of the command value of the ignition timing generated so as to converge the rotation speed of the internal combustion engine to the target rotation speed. As a result, it becomes impossible to suppress the tendency of the rotation speed of the internal combustion engine to increase with respect to the target rotation speed, and the rotation speed of the internal combustion engine actually increases to a rotation speed higher than the target rotation speed. .

Therefore, in the technique proposed by the applicant of the present application in Japanese Patent Application No. 9-109197, a certain amount of time elapses after the internal combustion engine is started in consideration of the reduction in friction after the internal combustion engine is started. Then, the amount of increase in the intake air amount of the internal combustion engine is gradually decreased according to a predetermined time table, thereby suppressing the increasing tendency of the rotational speed of the internal combustion engine due to the reduction of friction. Then, by suppressing the rising tendency of the rotation speed of the internal combustion engine in this way, it is possible to avoid a situation in which the command value of the ignition timing generated by the feedback control process described above exceeds the retard side limit value. I have to.

However, the form of reduction in friction of the internal combustion engine depends on the fuel properties, the type of lubricating oil, the amount of lubricating oil,
Influenced by various factors such as lubricating oil temperature and cooling water temperature,
It was found by further study by the inventors of the present application that the friction is often greater than usual or is likely to be reduced early.

In such a case, even if the increase amount of the intake air amount is gradually decreased from the time when a certain time elapses after the internal combustion engine is started as described above, the feedback control process described above is performed. In many cases, the command value of the generated ignition timing exceeds the retard side limit value, and as a result, the actual ignition timing of the internal combustion engine is limited to the retard side limit value, and the internal combustion engine rotation speed is reduced. There is a disadvantage that it may not be possible to prevent the number from increasing with respect to the target rotation speed.

Further, in the technique proposed by the applicant of the present application in the above-mentioned Japanese Patent Application No. 9-109197, for example, proportional integral control (PI control) is adopted as a feedback control method of the ignition timing based on the rotational speed of the internal combustion engine. is doing. In this proportional-plus-integral control, a proportional term proportional to the deviation between the internal combustion engine rotation speed (actual rotation speed) and the target rotation speed, and an integration according to the integrated value (deviation integrated value) of the deviation for each control cycle In order to converge the rotation speed of the internal combustion engine to the target rotation speed by calculating and adding the term and for each control cycle to obtain the correction amount of the ignition timing and correcting the basic ignition timing by the correction amount. The ignition timing command value is calculated.

In this case, the command value of the ignition timing thus generated exceeds the retard side limit value as described above, and the actual ignition timing is continuously maintained at the retard side limit value. In this state, the value of the PI control integral term increases on the retard side of the ignition timing. Therefore, when the actual ignition timing is kept at the retard side limit value, the PI control is performed when the internal combustion engine rotation speed decreases to the target rotation speed due to an increase in the internal combustion engine load or the like. However, the time required for the value of the integral term to change to the advance side to a value that can suppress the downward trend of the rotation speed of the internal combustion engine tends to be long. As a result, the tendency of the internal combustion engine to decrease in rotation speed cannot be quickly suppressed, and the rotation speed may drop significantly with respect to the target rotation speed.

The above-mentioned inconvenience is caused by the PI control.
Further, even when PID control in which a differential term is added is adopted, the same inconvenience occurs.

[0017]

SUMMARY OF THE INVENTION In view of the above background, the present invention is designed to increase the intake air amount of the internal combustion engine after starting the internal combustion engine as compared with during normal idling operation in order to activate the catalyst device early. A control device for an internal combustion engine, which feedback-controls an ignition timing so as to converge the rotational speed of the internal combustion engine to a required target rotational speed, is capable of improving the controllability and stability of the rotational speed of the internal combustion engine. An object is to provide a control device.

[0018]

In order to achieve such an object, a control device for an internal combustion engine according to the present invention provides a control system for an internal combustion engine that discharges exhaust gas through the cleaning device after the internal combustion engine is started.
Idling luck in operating mode for early activation
At the time of rotation, change the intake air amount of the internal combustion engine to a value other than the above operation mode.
Intake air amount control means for increasing the intake air amount by a predetermined increase from the intake air amount during idling operation in the mode, and after the increase of the intake air amount is started, the rotational speed of the internal combustion engine is converged to a predetermined target rotational speed. An ignition timing for correcting the ignition timing to a retard side by generating a command value for the ignition timing of the internal combustion engine by feedback control processing and controlling the ignition timing for the internal combustion engine based on the generated command value for the ignition timing. In a control device for an internal combustion engine including a control means, an ignition timing command value generated by the ignition timing control means by the feedback control processing is within a predetermined allowable range of the ignition timing at which the internal combustion engine can normally operate. When it becomes a value on the retard side of a predetermined threshold value set on the retard side of the ignition timing,
It is characterized in that the intake air amount control means is provided with a means for correcting the increase amount of the intake air amount to the decrease side of the intake air amount.

According to the present invention, when the intake air amount control means controls the increase of the intake air amount of the internal combustion engine and the ignition timing control means controls the ignition timing of the internal combustion engine, When the rotational speed of the internal combustion engine tends to increase with respect to the target rotational speed due to a decrease in friction of each part, the ignition timing control means generates the ignition of the internal combustion engine by a feedback control process based on the rotational speed of the internal combustion engine. The command value of the timing shifts to the retard side of the ignition timing. Then, as this transition progresses, the command value of the ignition timing becomes a value on the retard side with respect to the threshold value,
In such a state, the intake air amount control means
The increase amount of the intake air amount is corrected to the decrease side of the intake air amount. Therefore, the increasing tendency of the rotation speed of the internal combustion engine is suppressed, and the command value of the ignition timing is further suppressed from being retarded. Then, at this time, since the threshold value is within the allowable range of the ignition timing, the command value of the ignition timing is likely to be within the allowable range. In other words,
When the command value of the ignition timing is likely to deviate from the allowable range to the retard side due to the increasing tendency of the internal combustion engine speed, the intake air amount increase is corrected to the decrease side, and the internal combustion engine speed is changed. By suppressing the increasing tendency of the number, it becomes difficult for the state in which the command value of the ignition timing actually continuously deviates from the allowable range to the retard side. As a result, in a situation where the engine speed of the internal combustion engine tends to increase with respect to the target engine speed due to a decrease in friction of the internal combustion engine or the like, generation of an ignition timing command value that deviates from the allowable range to the retard side. While avoiding, the ignition timing of the internal combustion engine can be controlled according to the command value of the ignition timing generated so as to converge the rotational speed of the internal combustion engine to the target rotational speed. Then, by such control, stability of convergence of the rotation speed of the internal combustion engine to the target rotation speed is enhanced.

Therefore, according to the present invention, in controlling the intake air amount and the ignition timing of the internal combustion engine for the early activation of the catalyst device, the controllability and stability of the rotational speed of the internal combustion engine can be improved. .

According to the present invention, the intake air amount control means is in a state where the command value of the ignition timing generated by the ignition timing control means by the feedback control processing is a value on the retard side with respect to the predetermined threshold value. It is preferable to gradually increase the correction amount to the decreasing side of the increase amount of the intake air amount.

In this way, by gradually increasing the correction amount to the decrease side by the increase amount of the intake air amount in the state where the command value of the ignition timing is on the retard side of the predetermined threshold value, Even if the internal combustion engine has a relatively large increase in the rotational speed due to a relatively large decrease in friction, the generated ignition timing command value may deviate from the allowable range to the retard side. It is possible to avoid the situation, and at the same time, it is possible to avoid a sudden change in the rotation speed and ignition timing of the internal combustion engine, and to secure the stability of the operating state or combustion state of the internal combustion engine.

In this case, when gradually increasing the correction amount to the decreasing side by the increase amount of the intake air amount as described above, the correction amount is a predetermined amount set according to the warm-up state of the internal combustion engine. It is particularly preferable to increase the value every predetermined control cycle.

That is, the form of the temporal change of the friction reduction of the internal combustion engine basically depends on the warm-up state of the internal combustion engine (for example, the engine temperature), and therefore, it corresponds to the increase in the intake air amount. By increasing the correction amount to the decreasing side by a predetermined amount set according to the warm-up state of the internal combustion engine, for each predetermined control cycle, the amount of increase in the intake air amount is set to the friction reduction time of the internal combustion engine. It can be reduced according to the form of dynamic change. Therefore, it is possible to accurately suppress the increase tendency of the rotation speed of the internal combustion engine due to the reduction of the friction of the internal combustion engine, in which the command value of the ignition timing easily deviates from the allowable range to the retard side.

Further, in the case of gradually increasing the correction amount to the decreasing side of the increase amount of the intake air amount as described above, when the correction amount to the decreasing side of the increase amount of the intake air amount is performed. When the command value of the ignition timing generated by the ignition timing control means by the feedback control process changes to the advance side from the threshold value, the current correction amount of the intake air amount increase is decreased. It is preferable to keep the amount. That is, the fact that the command value of the ignition timing changes to the advance side from the threshold value during the correction of the increase amount of the intake air amount to the decrease side does not mean that the increase amount of the intake air amount is further corrected to the decrease side. In addition, since the increasing tendency of the rotation speed of the internal combustion engine is suppressed, by holding the correction amount of the increased amount in the present state, the increased amount of the intake air amount is excessively decreased to reduce the internal combustion engine. It is possible to avoid a situation in which the amount of heat generation becomes too small, and thus it is possible to ensure early activation of the catalyst device.

Further, in the present invention, the threshold value may be set to a retard side limit value of the allowable range, for example. However, the threshold value is advanced to the retard side of the allowable range of the ignition timing. Is preferably set to. By thus setting the threshold value on the advance side with respect to the retard side limit value, the command value of the ignition timing reaches the retard side limit value with the increasing tendency of the rotation speed of the internal combustion engine. Before, since the increasing tendency of the rotation speed of the internal combustion engine is suppressed by the correction of the increase amount of the intake air amount to the decreasing side, the command value of the ignition timing is
Within the permissible range, it becomes easier and more reliable. Therefore, the ignition timing of the internal combustion engine can be controlled more reliably according to the command value of the ignition timing, and the controllability and stability of the rotation speed of the internal combustion engine can be further enhanced.

Further, in the present invention, the ignition timing control means successively generates a command value of the ignition timing of the internal combustion engine by using proportional integral control (PI control) as the feedback control processing, and the generated ignition is carried out. When the command value of the timing becomes a value on the retard side of the retard side of the allowable range of the ignition timing or more, the ignition timing of the internal combustion engine is limited to the retard side limit value, and the proportional integration is performed. The value of the integral term in control is held at the current value.

According to this, even if the intake air amount is increased and the intake air amount is corrected to a decreasing side due to a sudden decrease in the load of the internal combustion engine, the increasing tendency of the internal combustion engine speed cannot be immediately suppressed, and the ignition When the command value of the timing becomes a value on the retard side of the retard side limit value of the allowable range of the ignition timing or more, the ignition timing of the internal combustion engine is advanced from the command value of the ignition timing. By limiting to the retard side limit value, the rotation speed of the internal combustion engine increases. However, at this time, the value of the integral term of the proportional-plus-integral control for generating the command value of the ignition timing is held at the current value, and thereafter, the intake air amount is further decreased by the increase amount or the internal combustion engine When the rotation speed of the internal combustion engine turns downward with respect to the target rotation speed due to a sudden increase in load, the command value of the ignition timing generated in the proportional-plus-integral control is promptly set to the retard side limit value. Also turns to the advance side. Therefore, it becomes possible to quickly control the ignition timing of the internal combustion engine according to the command value of the ignition timing,
It is possible to quickly suppress the downward trend of the rotation speed of the internal combustion engine and ensure the convergence of the rotation speed to the target rotation speed.

In the present invention, the proportional-plus-integral control includes proportional-plus-integral-derivative control (PID control) in which a derivative term is further added in addition to the proportional term and the integral term.

Further, in the present invention, after the intake air amount control means starts the increase control of the intake air amount, the rotational speed of the internal combustion engine becomes a predetermined set rotational speed which is set higher than a predetermined idling rotational speed. After reaching the target rotation speed, the target rotation speed is set while changing the target rotation speed from the set rotation speed toward the idling rotation speed.

As described above, after the increase of the intake air amount during the idling operation after the internal combustion engine is started, the rotation speed of the internal combustion engine becomes higher than the predetermined target idling speed, which is the final target rotational speed. After the number reaches, by changing the target rotation speed for performing the feedback control of the ignition timing from the set rotation speed toward the idling rotation speed, the rotation of the internal combustion engine is started by the feedback control of the ignition timing. It is possible to avoid the situation where the operation of the internal combustion engine becomes unstable due to a sudden drop in the engine speed or a drastic drop of the engine speed from the final target engine speed, the idling engine speed. .

Further, in the present invention, the intake air amount control means sets the increased amount of the intake air amount in the uncorrected state according to the engine temperature of the internal combustion engine.

That is, for example, in a state where the engine temperature of the internal combustion engine is relatively high, if the heat generation amount of the internal combustion engine is excessively increased by the intake air amount increase control and the ignition timing feedback control, the internal combustion engine is burdened. In many cases, the temperature of the catalyst device is relatively high when the engine temperature is relatively high. Therefore, by setting the increase amount of the intake air amount according to the engine temperature of the internal combustion engine, control is performed such that the internal combustion engine is overloaded or the combustion heat of the internal combustion engine becomes unnecessarily large. Such a situation can be avoided.

Further, in the present invention, the intake air amount control means controls the increase amount of the intake air amount in the uncorrected state so as to gradually increase immediately after the internal combustion engine is started. That is, if the intake air amount is increased stepwise immediately after the internal combustion engine is started, the operating state of the internal combustion engine may become unstable, but as described above, the intake air amount is gradually increased. By doing so, it is possible to avoid a situation in which the operating state of the internal combustion engine becomes unstable.

Further, according to the present invention, the intake air amount control means sets a predetermined time after starting the increase control of the intake air amount for the increase amount in the uncorrected state of the increase amount of the intake air amount. After that, it is controlled so as to gradually decrease with the passage of time in a predetermined form. In this way, even in the uncorrected state of the intake air amount increase, by gradually decreasing the intake air amount increase amount after a predetermined time has elapsed from the start of the intake air amount increase control, As described above, when the command value of the ignition timing becomes a value on the retard side with respect to the threshold value, the increase amount of the intake air amount is corrected to the decrease side, and at the same time, the internal combustion engine is reduced due to the reduction of friction. The rising tendency of the engine speed can be suppressed appropriately.

[0036]

DETAILED DESCRIPTION OF THE INVENTION An embodiment of the present invention will be described with reference to FIGS.

FIG. 1 shows a system configuration of a control device for an internal combustion engine according to the present embodiment. Reference numeral 1 is an internal combustion engine, and 2 is a controller for controlling the internal combustion engine 1.

The internal combustion engine 1 is mounted on a vehicle such as an automobile or a hybrid vehicle as a propulsion source thereof, and discharges exhaust gas into the atmosphere via a catalyst device 3 composed of, for example, a three-way catalyst.

In the system of the present embodiment, as an auxiliary structure for controlling the operation of the internal combustion engine 1, a rotational speed sensor 4 for detecting the rotational speed NE of the internal combustion engine 1, an engine temperature of the internal combustion engine 1 (cooling water temperature). Engine temperature sensor 5 for detecting TW, intake pressure sensor 6 for detecting intake pressure PB of the internal combustion engine 1, atmospheric temperature
Various sensors such as an atmospheric temperature sensor 7 for detecting TA, an accelerator sensor 8 for detecting an operation amount AP of an accelerator pedal not shown, and a vehicle speed sensor 9 for detecting a vehicle speed V are provided. Further, as an auxiliary structure for driving the internal combustion engine 1, an ignition device 10 for igniting an air-fuel mixture of the internal combustion engine 1 is provided.
A fuel supply device 11 that supplies fuel to the internal combustion engine 1, a throttle actuator 12 that drives a throttle valve (not shown) of the internal combustion engine 1, and the like are provided. Although illustration is omitted, intake of the internal combustion engine 1 is performed through both a flow passage provided with a throttle valve and a bypass flow passage bypassing the throttle valve.

Although not shown in the figure, in addition to the above configuration,
A starter motor for starting the internal combustion engine 1, a power source battery for various electronic devices, and a transmission for transmitting power of the internal combustion engine 1 to drive wheels (an automatic transmission in the system of the present embodiment).
It is needless to say that the above-mentioned mechanism and the like are provided in the same manner as in a normal automobile, and that the pumps driven by the internal combustion engine 1 associated with the power steering device, the air conditioner device, etc. Provided as part.

The controller 2 is constructed by using a microcomputer, and the various sensors 4 to 4 described above are used.
The ignition device 10, the fuel supply device 11, the throttle actuator 12 and the like are controlled on the basis of the output (detection value) of 9 and a predetermined program, a preset data value, etc. to perform the required operation of the internal combustion engine 1. .

The controller 2, as a main functional configuration according to the present invention, controls the throttle actuator 12 so as to increase the intake air amount of the internal combustion engine 1 during idling operation after the internal combustion engine 1 is started. Air amount control means 13, target speed setting means 14 for setting a target speed of the internal combustion engine 1 when the intake air amount is increased, and ignition of the internal combustion engine 1 by the ignition device 10 based on the target speed. An ignition timing control means 15 for feedback-controlling the timing and a determination means 16 for performing a condition determination as to whether or not the control by the intake air amount control means 13 and the ignition timing control means 15 should be released (prohibited) are provided. Detailed functions of these respective means 13 to 16 will be described later.

Next, the operation of the system of this embodiment will be described.

First, an outline of the basic operation of the system of this embodiment will be briefly described with reference to FIG. Figure 2
The upper, middle, and lower stages show exemplary forms of changes over time in the opening of the throttle valve, the ignition timing, and the rotational speed of the internal combustion engine 1 in the system of the present embodiment, respectively.

Referring to FIG. 2, in the system of this embodiment, when the system is started by operating a start switch (not shown) while the internal combustion engine 1 is stopped, the operation of the system is as follows. 1 is performed by a starter motor (not shown) while starting the internal combustion engine 1 (hereinafter referred to as a start mode). In this starting mode, the opening degree of the throttle valve and the ignition timing are controlled as shown in the figure, and the rotation speed of the internal combustion engine 1 changes as shown in the figure.

Next, when the so-called complete explosion of the internal combustion engine 1 is confirmed in this starting mode, the operation of the system is a control for early activation of the catalyst device 3 while performing the idling operation of the internal combustion engine 1. Operation mode (hereinafter, CW
U mode).

In the CWU mode, first, the internal combustion engine 1
The throttle valve opening THO (hereinafter referred to as throttle opening THO) that regulates the intake air amount of the intake air amount of the internal combustion engine 1 is increased (THO>
By controlling to 0), the intake air amount is increased as compared with the normal idling operation of the internal combustion engine 1. Here, in the system of the present embodiment, the throttle opening THO is "0" during normal idling operation of the internal combustion engine 1 (during idling operation other than the CWU mode) when the vehicle is temporarily stopped during traveling. In this state, the intake air of the internal combustion engine 1 is performed only through the bypass passage bypassing the throttle valve. Therefore, the intake air amount of the internal combustion engine 1 in the CWU mode is increased by the control of the throttle opening THO as described above in the same manner as the throttle opening THO as compared with the normal idling operation. (Throttle opening THO corresponds to the throttle opening including the increase in intake air amount compared to normal idling operation).

The form of change in the throttle opening THO, that is, the form of change in the amount of increase in the intake air amount is appropriately corrected to the side in which the amount of increase is decreased under the required conditions.

In addition, the rotational speed NE of the internal combustion engine 1 in the CWU mode increases as the intake air amount increases (throttle opening THO increases) in the form shown by the solid line in the lower part of FIG. When the number of revolutions reaches a set number of revolutions higher than the predetermined idling speed NOBJ by a predetermined amount NECPIS,
The ignition timing IGLOG of the internal combustion engine 1 is controlled to the retard side in the form shown by the solid line in the middle stage.

In the control of retarding the ignition timing IGLOG, the target engine speed NE / CWU of the internal combustion engine 1 is set in the form shown by the broken line in the lower part of FIG. The target speed NE / CWU
Is reduced from the set rotational speed (NOBJ + NECPIS) toward the required idling rotational speed NOBJ at a predetermined degree (inclination), and is maintained at the idling rotational speed NOBJ after reaching the idling rotational speed NOBJ. . The idling speed NOBJ is set to be higher than the speed during normal idling operation.

The target rotational speed set in this way
Feedback control processing (PI control is adopted in this embodiment) so as to converge the rotational speed NE of the internal combustion engine 1 to the NE / CWU.
Therefore, the correction amount IG / CPID for retarding the ignition timing (indicated by a broken line in the middle of FIG. 2; hereinafter referred to as the retard correction amount IG / CPID).
Ignition time IGBASE
The ignition timing IGLOG (more accurately, the command value of the ignition timing) is determined by correcting (indicated by the one-dot chain line in the middle of FIG. 2).

Next, for example, when the driver of the vehicle operates the accelerator pedal to start the vehicle in the middle of the CWU mode as described above, the CWU mode is released and the operation of the system is carried out according to the operation of the accelerator pedal. Organization 1
The operation mode (hereinafter, referred to as a normal mode) in which the operation is performed shifts to. In this normal mode, the throttle valve opening TH
O is immediately controlled according to the operation amount of the accelerator pedal (see the upper right part of FIG. 2). In addition, the internal combustion engine 1
The ignition timing IGLOG of is gradually returned to the original ignition timing IGBASE on the advance side after the CWU mode is released, as shown in the middle right part of FIG.

The CWU mode may be omitted depending on the situation, and may be released under conditions other than the operation of the accelerator pedal.

Based on the above, the detailed operation of the system of this embodiment will be described below.

When the system of this embodiment is started up with the internal combustion engine 1 stopped, the controller 2 executes the main routine processing shown in the flowchart of FIG. 3 in a predetermined control cycle. The control cycle is the crank angle cycle (= TDC) in this embodiment.

The controller 2 first determines whether or not the operation mode of the system is the starting mode (ST).
EP3-1). This determination is made, for example, based on whether or not a so-called complete explosion of the internal combustion engine 1 is confirmed, and the operation mode is the start mode until the complete explosion is confirmed. The confirmation of the complete explosion is performed based on the output (rotational speed NE) of the rotational speed sensor 4.

If it is determined in STEP 3-1 that the operation mode is the start mode, the controller 2 performs the start mode process (S) for operating the internal combustion engine 1 in the start mode.
After performing TEP3-2), the processing of this control cycle is ended.

In the start-up mode process, the controller 2 sets the fuel supply amount to the internal combustion engine 1, the ignition timing, and the command value of the throttle opening THO to the detected values of the various sensors 4 to 8 and a predetermined map, respectively. , Is determined based on an arithmetic expression or the like. Then, by operating the fuel supply device 11, the ignition device 10, and the throttle actuator 12 in accordance with the determined command value, the internal combustion engine 1 is cranked by a starter motor (not shown),
The internal combustion engine 1 is started.

In the start mode processing, the controller 2 controls the CWU mode (details will be described later).
Initialize various parameters such as flags for performing.

Here, the parameter for initial setting is C
In the WU mode, the ignition timing retard correction amount IG / CPID (n) (n in parentheses indicates the number of control cycles. The same applies below) and the ignition timing correction amount IG / CPID. (n)
Term when the proportionality integral control (PI control) is calculated
I / IGCWU (n) and the count value T / CWU of the count-up timer (hereinafter, CWU elapsed time T / CWU) that counts the elapsed time in CWU mode (elapsed time after the start mode ends), A flag F / CWUON (hereinafter referred to as CWU availability flag F / CWUON) indicating whether or not the operation mode is the CWU mode, and whether or not the ignition timing is retarded or is being corrected. Flag F / NEFB (hereinafter,
The retard correction propriety flag F / NEFB) and the command value IGLOG of the ignition timing obtained as described later in the CWU mode are on the retard side of the predetermined threshold value and the throttle opening THO (increase in the intake air amount) Flag F / THODEC (hereinafter, increase correction flag F /
THODEC) and the correction amount THO / DEC of the throttle opening THO when correcting the increase of the intake air amount (this corresponds to the correction amount of the increase of the intake air amount. Below, throttle correction amount THO / DEC The value of each of these parameters is set to "0".

The value of the CWU enable / disable flag F / CWUON means that the operation mode is the normal mode when it is "0", and the operation mode is the CWU mode when it is "1". Means that. Similarly, when the value of the retard correction allowance flag F / NEFB is "0", it means that the ignition timing is not corrected to the retard side, and when it is "1", the ignition correction is performed. It means that the timing is retarded or is being corrected. When the value of the increase correction flag F / THODEC is "0", it means that the throttle opening THO should not be corrected to the decrease side, and when it is "1", the throttle opening is set. This means that the THO should be corrected to the decreasing side.

In the starting mode process, the engine temperature TW at the time of starting the internal combustion engine 1 is detected by the engine temperature sensor 5 and stored in a memory (not shown).

On the other hand, when the operation mode is not the starting mode (when complete combustion of the internal combustion engine 1 is confirmed) in the determination of STEP3-1, the controller 2 instructs the fuel supply amount to the internal combustion engine 2 to be a command value. Is calculated (STEP3-3), and the judgment means 16 further judges whether or not the CWU mode control should be performed (STEP3-3).
4) The opening command value THO of the throttle valve of the internal combustion engine 1 is calculated by the intake air amount control means 13 (STEP3
-5), and the command value IGLOG of the ignition timing of the internal combustion engine 1
Is calculated by the ignition timing control means 15 (ST
EP3-6). Then, after performing these processes, the process of this control cycle is ended.

In the calculation process of the command value of the fuel supply amount in STEP 3-3, first, the rotational speed NE of the internal combustion engine 1 detected by the rotational speed sensor 4 and the intake pressure sensor 6 is detected.
And the basic fuel supply amount is obtained from the intake pressure PB using a preset map, and the basic fuel supply amount is further detected by the engine temperature sensor 5 and the atmospheric temperature sensor 7 such as the engine temperature TW and the atmospheric temperature TA. The command value of the fuel supply amount is calculated by performing the correction according to

The command value of the fuel supply amount calculated in this way is given from the controller 2 to the fuel supply device 11, and the fuel supply device 11 supplies the fuel to the internal combustion engine 1 according to the given command value. I do.

The condition judgment in STEP3-4 is made by the judgment means 16 of the controller 2 as shown in the flow chart of FIG.

That is, the judging means 16 first determines whether or not the present CWU elapsed time T / CWU is within a predetermined time limit TCWULMT (whether T / CWU <TCWULMT). Judge (STEP4-1), T / CWU ≧ TC
If it is WULMT, the CWU availability flag F / CWUON
Is set to the normal mode (STEP 4-11), and the value of CWU elapsed time T / CWU is forcibly set to the time limit TCWULMT (STEP 4-12). The above time limit TCWULM
T is an internal combustion engine 1 which will be described later within the time limit TCWULMT.
By increasing the intake air amount and controlling the ignition timing to the retard side (control in the CWU mode), a time is set such that the catalyst device 3 rises to a temperature at which it is sufficiently activated.

When the condition of STEP 4-1 is satisfied, the determination means 16 further sets the retard angle correction availability flag set in the flowchart (FIG. 10) of the calculation process of the retard angle correction amount described later. When the current value of F / NEFB is judged (STEP4-2), and if F / NEFB = 0, the current CWU elapsed time T / CWU is a predetermined time limit TCWUNG (this time limit TCWUNG is the above-mentioned STEP4- Whether it is within the time limit TCWULMT in the judgment of 1) (T / CWU <
(Whether it is TCWUNG) is determined (STEP4-3).
In this determination, if T / CWU ≥ TCWUNG, that is, the state where the ignition timing is retarded is not corrected (F / NEFB = 0), the elapsed time after the start mode is ended (= CWU When the elapsed time T / CWU) is equal to or longer than the predetermined time limit TCWUNG, the above STEP4-11, 4-12
Is processed (normal mode setting).

When F / NEFB = 1 in the judgment of STEP4-2, or T / CWU <in the judgment of STEP4-3.
If it is TCWUNG, the determination means 16 further determines whether the vehicle speed V detected by the vehicle speed sensor 9 is smaller than a predetermined value V / CWUL and the vehicle is in a stopped state (STEP).
4-4) and the detected value of the accelerator pedal operation amount AP by the accelerator sensor 8 is smaller than a predetermined value APCLOSE,
Judgment of whether or not the accelerator pedal is almost fully closed (S
TEP4-5) are sequentially performed. And those STE
When the conditions of P4-4 and 4-5 are not satisfied (when not in the idling operation state), the above STEP4-1 is performed.
Processes 1 and 4-12 are performed (normal mode setting).
Further, when each of the conditions of STEPs 4-4 and 4-5 is satisfied, that is, when the internal combustion engine 1 is in the idling operation state, the determination means 16 further causes the rotation speed sensor 4 to rotate the internal combustion engine 1. It is judged whether the detected value of the number NE is within a predetermined range (STEP 4-6) and whether the engine temperature TW of the internal combustion engine 1 by the engine temperature sensor 5 is within a predetermined range (STEP 4-6). 7) and are sequentially performed. Then, if the conditions of STEP 4-6 and 4-7 are not satisfied, the processing of STEP 4-11 and 4-12 is performed (normal mode setting).

When the conditions of STEP 4-6 and 4-7 are satisfied, the determination means 16 further determines the air conditioner device (more accurately, the compressor associated with the air conditioner device) and the power steering device (not shown). To be more precise, the hydraulic pump attached to the hydraulic power steering device)
Is in the OFF state, that is, whether the clutch of the compressor of the air conditioner is in the disengaged state or the hydraulic pump of the power steering device is in the no-load state (STEP4-8, 4-9). If the device or the power steering device is not in the OFF state and either is operating, the above STEP4-11,
The process 4-12 is performed (normal mode setting). Also, S
When the conditions of TEP4-8 and 4-9 are satisfied (in this case, all the conditions of STEP4-1 to 4-9 are satisfied), the value of the CWU permission flag F / CWUON is set to "1".
Is set to CWU mode (STEP 4-10).

By the condition determination processing by the determination means 16 as described above, after the internal combustion engine 1 is started, the state of the vehicle, the air conditioner device, the power steering device, which is the load of the internal combustion engine 1, the rotational speed NE of the internal combustion engine 1, Engine temperature TW and
When the CWU elapsed time T / CWU satisfies the conditions of STEPs 4-1 to 4-9, the CWU mode is set (C
WU enable / disable flag F / CWUON = 1).

Then, immediately after the internal combustion engine 1 is started, the vehicle, the air conditioner device, and the power steering device, which are loads on the internal combustion engine 1, should be driven, or in such a condition, the CWU mode is set. If it occurs during the operation, the above STEP 4-4, 4-5,
Since the conditions 4-8 and 4-9 are not satisfied, the system operation mode is set to the normal mode immediately after the start,
Alternatively, the CWU mode is canceled midway and the normal mode is set (CWU enable / disable flag F / CWUON = 0).

Similarly, the rotational speed NE of the internal combustion engine 1 and the engine temperature
In situations where TW is too high or too low, the STE
Since the conditions of P4-6 and 4-7 are not satisfied, the operation mode of the system is set to the normal mode immediately after the start, or the CWU mode is canceled midway and the normal mode is set (CWU enable / disable). Flag F / CWUON =
0).

The elapsed time of the operation of the internal combustion engine 1 in the CWU mode (= CWU elapsed time T / CWU) is the time limit.
TCWULMT or more (STEP4-1 condition is satisfied), or the ignition timing is not corrected to the retard side (F / NEFB = 0), and the CWU elapsed time T / CWU is a predetermined time limit. When TCWUNG or more (STEP4-3 condition is satisfied. In such a state, in the CWU mode, the rotation speed of the internal combustion engine 1 is affected by, for example, the fuel property.
The CWU mode is canceled and the normal mode is set (which occurs when the NE does not reach the set rotation speed described later forever) (CWU enable / disable flag F / CWUON = 0). By this process, in a state where the rotation speed of the internal combustion engine 1 rises badly (in other words, the combustion state is bad) for some reason, the combustion can be stabilized by canceling the CWU mode.

When the normal mode is set, as long as the operation of the internal combustion engine 1 continues, the CWU
Elapsed time T / CWU is time limit TCWULMT in STEP4-12
After that, the condition of STEP 4-1 is not satisfied until the internal combustion engine 1 is restarted (CW
U elapsed time T / CWU is initialized only in the start mode), and therefore CWU mode is set when the vehicle is running or when the vehicle is idling (temporarily idling). There is no such thing.

That is, in the CWU mode, only during the first idling operation after starting the internal combustion engine 1, under predetermined conditions such as the load state of the internal combustion engine 1, the rotational speed NE, the engine temperature TW, etc.
It is set within the time limit TCWULMT.

In the present embodiment, the engine temperature TW is used for determining the condition of the CWU mode including the meaning of substituting the temperature state of the catalyst device 3, but the temperature of the catalyst device 3 is directly detected and this is used. It may be used for condition determination in the CWU mode.

Although not adopted in this embodiment,
The operation mode of the system may not be set to the CWU mode until a certain amount of time elapses after the start mode ends.

Next, the calculation process of the throttle valve opening command value THO in STEP 3-5 of FIG. 3 is performed by the intake air amount control means 13 of the controller 2 as shown in the flowcharts of FIGS. 5 and 6. Be seen.

That is, referring to FIG. 5, the intake air amount control means 13 first sets the command value THO / CWU of the throttle opening in the CWU mode to the start mode processing (STE).
In P3-2), it is calculated based on the engine temperature TW detected by the engine temperature sensor 5 and the CWU elapsed time T / CWU (STEP 5-1).

More specifically, in the calculation process of STEP 5-1, as shown in FIG. 6, the intake air amount control means 1
3. First, the value of the CWU enable / disable flag F / CWUON is judged (STEP6-1), and when F / CWUON = 1, that is, the operation mode is set to the CWU mode by the condition judgment of STEP3-4. In the case of the CWU mode, the throttle opening command value THO / for increasing the intake air amount of the internal combustion engine 1 compared to the normal idling operation is used.
The basic value THO / CTBL of CWU is calculated from the detected value of the engine temperature TW obtained during the start mode processing using a predetermined data table as shown in FIG. 7 (STEP6
-2). Here, this data table shows that the basic value THO / CTBL of the throttle opening command value THO / CWU becomes almost constant in the low and medium temperature range of the engine temperature TW, and the throttle opening command value in the high temperature area. It is set to reduce the basic value THO / CTBL of THO / CWU.

Next, the intake air amount control means 13 causes the increase correction flag F / THOD to be set in the flow chart (FIG. 11) for limiting the command value of the ignition timing IGLOG, which will be described later.
Judging the current value of EC (STEP6-3), F / THODEC =
When it is 0 (when it is not in a state where the throttle opening THO should be corrected to the decreasing side), the processing of STEP 6-6 is performed.

When F / THODEC = 1 (when the throttle opening THO should be corrected to the decreasing side), the intake air amount control means 13 controls the throttle opening.
Unit correction value for each THO control cycle d / THODEC (> 0)
From the detected value of the engine temperature TW obtained during the starting mode processing (this represents the warm-up state at the time of starting the internal combustion engine 1) using a predetermined data table as shown in FIG. (STEP6-4). Here, this data table shows the unit correction value in the low and medium temperature range of the engine temperature TW.
The d / THODEC is set to a relatively small value, and the unit correction value d / THODEC is set to be large in the high temperature region.
Then, the intake air amount control means 13 uses the calculated unit correction value d / THODEC as the current throttle correction amount THO / DEC.
(This is initialized to "0" in the start mode process)
After updating the throttle correction amount THO / DEC (STEP 6-5), the processing of STEP 6-6 is performed.

Next, at STEP 6-6, the intake air amount control means 13 corrects the basic value THO / CTBL of the throttle opening command value THO / CWU obtained at STEP 6-2 according to the CWU elapsed time T / CWU. Basic value correction factor KM / CWU
From the CWU elapsed time T / CWU using a predetermined data table (time table) as shown in FIG. The basic value correction coefficient KM / CWU is a coefficient (≦ 1) for correcting the basic value THO / CTBL by multiplying it by the basic value THO / CTBL, and in the data table of FIG.
The basic value correction coefficient KM / CWU gradually increases with the passage of time toward the maximum value "1" at the initial stage (time 0 to t1) of the CWU elapsed time T / CWU, and thereafter, reaches the maximum value for a predetermined time. After being continuously maintained at "1" (time t1 to t2), it is set to gradually decrease with the passage of time.

The data table as described above is set separately when the lever of the automatic transmission (not shown) of the vehicle is in the N range (neutral range) and in the D range (drive range). You may keep it. This is because the load applied to the internal combustion engine 1 differs between the N range and the D range, and the combustion state of the internal combustion engine 1 can be controlled more optimally by setting the data table according to the load. Becomes

Further, in the data table of FIG. 9, the CWU elapsed time T /
Basic value correction coefficient KM at the initial stage of CWU (time 0 to t1)
/ CWU may be gradually increased in the form shown by the dotted line in FIG. 9, for example.

Next, the intake air amount control means 13 starts ST
The basic value THO / CTBL of the throttle opening command value THO / CWU obtained in EP6-2 is multiplied by the basic value correction coefficient KM / CWU obtained in STEP6-6, and from the multiplication result, the current value Throttle correction amount THO / DEC (F6 in STEP 6-3
THODEC = 0), or throttle correction amount THO / DEC updated in STEP6-5 (F / TH in STEP6-3)
The command value THO / CWU of the throttle opening in the CWU mode is calculated by subtracting (ODEC = 1) (ST
EP6-7).

The intake air amount control means 13 uses the STEP
The command value THO / CWU of the throttle opening calculated in 6-7 is
It is judged whether or not it is within a range between a predetermined upper limit value THCWUH and a lower limit value THCWUL (STEP6-8, 6-
9) If the upper limit value THCWUH is exceeded or the lower limit value THCWUL is exceeded, the throttle opening command value THO / CWU is limited to the upper limit value THCWUH and the lower limit value THCWUL, respectively (STEP 6-10, 6). -11).

Further, in the judgment of STEP6-1, the F / CW
When UON = 0, that is, when the normal mode is set in the condition judgment of STEP3-4, the command value THO / CWU of the throttle opening and the value of the basic value correction coefficient KM / CWU are cleared. Yes (set each value to "0". STE
P6-12).

Returning to FIG. 5, after obtaining the throttle opening command value THO / CWU in the CWU mode as described above,
The intake air amount control means 13 uses the CWU availability flag F / CW.
If the value of UON is judged (STEP 5-2) and F / CWUON = 1 (when CWU mode is set),
Set the final throttle opening command value THO to STEP 5-1.
Determined to the command value THO / CWU obtained in (STEP5-
3). When F / CWUON = 0 in the judgment of STEP5-2 (when the normal mode is set), the intake air amount control means 13 sets the final throttle opening command value THO to the accelerator. A value corresponding to the detected value of the pedal operation amount AP is determined (STEP 5-4). In this case, the throttle opening command value THO according to the accelerator pedal operation amount AP in the normal mode is "0" in a normal idling operation state in which the accelerator pedal is not operated, and CW
In the U mode, it is smaller than the opening command value THO / CWU obtained according to the engine temperature TW and the CWU elapsed time T / CWU as described above.

As described above, after the internal combustion engine 1 is started,
When the CWU mode is set in the condition judgment of STEP3-4, the command value THO of the throttle opening is determined according to the engine temperature TW and the CWU elapsed time T / CWU, and the normal mode is set. If it is performed, it is determined according to the operation amount AP of the accelerator pedal. Then, the controller 2 instructs the throttle actuator 12 with the throttle opening command value THO thus determined, and the throttle actuator 12 drives the throttle valve in accordance with the given throttle opening command value THO. . As a result, the intake air amount of the internal combustion engine 1 is controlled according to the throttle opening command value THO.

In this case, the command value TH of the throttle opening during idling operation of the internal combustion engine 1 in the CWU mode
O is for idling operation while the vehicle is temporarily stopped, etc.
Since it is determined to be larger than that during the normal idling operation in the normal mode, the intake air amount of the internal combustion engine 1 is increased as compared with that during the normal idling operation.

The command value THO (= THO / CWU) of the throttle opening in the CWU mode is the throttle correction amount.
When THO / DEC is “0” (uncorrected state of increasing intake air amount), the above-mentioned characteristics of the basic value correction coefficient KM / CWU timetable (see FIG. 9) As shown by the solid line in the upper part of FIG. 2, in the initial stage immediately after the start of the CWU mode, the temperature gradually rises toward the basic value THO / CTBL, and then the basic value THO / CTBL is continuously maintained. After that, the basic value THO / CTBL gradually decreases with the lapse of time, and the intake air amount of the internal combustion engine 1 is increased in comparison with the normal idling operation in the same manner. That is, the value obtained by multiplying the basic value THO / CTBL by the basic value correction coefficient KM / CWU defines the basic form of the increase of the intake air amount by the intake air amount control means 13 in the present embodiment. It is a thing. Further, the increase amount of the intake air amount in this case is set according to the engine temperature TW by setting the basic value THO / CTBL according to the engine temperature TW when the internal combustion engine 1 is started.

When the throttle correction amount THO / DEC is not "0" (THO / DEC> 0), the throttle opening THO is equal to the basic value THO / CTBL and the basic amount by the throttle correction amount THO / DEC. By reducing the basic throttle opening determined by the value correction coefficient KM / CWU (STEP6
(See -7), the amount of increase in the intake air amount is corrected to the decrease side with respect to the basic amount of increase by an amount corresponding to the throttle correction amount THO / DEC. In this case, when the increase correction flag F / THODEC is "1" (this is because the command value IGLOG of the ignition timing obtained using the feedback control process (PI control) as described later is later than the predetermined threshold value. The throttle correction amount THO / DEC is increased by the unit correction value d / THODEC for each control cycle by the processing of STEP 6-5, so that the intake air amount The correction amount to the decreasing side of the increase amount is increased in each control cycle by the amount corresponding to the unit correction value d / THODEC.

In this way, the throttle correction amount THO / DEC is
If the increase correction flag F / THODEC changes from "1" to "0" while the value is being increased by the unit correction value d / THODEC (details will be described later), the processing of STEP6-5 is not performed. Therefore, the throttle correction amount THO / DEC will not be updated and will be maintained at the current value.

Next, the calculation process of the command value IGLOG of the ignition timing of the internal combustion engine 1 in STEP 3-6 of FIG. 3 is performed by the target rotation speed setting means 14 and the ignition timing control means 15 of the controller 2 as shown in FIGS. 11 is performed as shown in the flowchart.

That is, with reference to FIG. 10, the ignition timing control means 15 first obtains the basic value IGMAP of the ignition timing (STEP 10-1). This basic value IGMAP is obtained, for example, from a map determined in advance from the detected value of the rotational speed NE of the internal combustion engine 1 and the detected value of the intake pressure PB.

Then, the ignition timing control means 15 sets the correction value IGHK for correcting the basic value IGMAP according to the detected value of the engine temperature TW of the internal combustion engine 1 and the detected value of the atmospheric temperature TA. Is obtained using a map or a predetermined arithmetic expression (STEP 10-2). This correction value IGHK is the basic value
The basic value IGMAP is corrected by adding it to IGMAP. In this case, the ignition timing determined by the value (IGMAP + IGHK) obtained by adding the correction value IGHK to the basic value IGMAP is the ignition timing IGBA on the advance side shown by the dashed line in the middle part of FIG.
SE (IGBASE = IGMAP + IGHK), which corresponds to the ignition timing on the advance side for properly operating the internal combustion engine 1 in the normal mode. Below, this ignition timing IGBA
SE is referred to as normal ignition timing IGBASE.

Next, the ignition timing control means 15 causes the CWU
In the mode, the retard correction amount IG / CPID for correcting the normal ignition timing IGBASE is calculated (STEP10-
3).

More specifically, in the calculation process of STEP10-3, as shown in FIG. 11, the ignition timing control means 15 first determines the value of the CWU enable / disable flag F / CWUON (STEP11-1). , If F / CWUON = 1, then
That is, when the CWU mode is set, the current value of the retard angle correction availability flag F / NEFB is determined (S
TEP 11-2). At this time, if F / NEFB = 0,
That is, in a state where the correction of the ignition timing to the retard side has not started yet, the value of the parameter T / CPIS for grasping the start time of the correction of the ignition timing to the retard side is set to the current CWU elapsed time T. / CWU (STEP 11-3). In addition, STE
If F / NEFB = 1 in the judgment of P11-2, ST
The processing of EP11-3 is omitted. Therefore, the value of the above parameter T / CPIS is the value of the delay angle correction availability flag F / NEFB,
CWU elapsed time T / CWU at that time (more precisely, one control cycle before) at the time when it is changed from "0" to "1" (when the ignition timing is retarded) Fixed to.

Next, the ignition timing control means 15 causes the target rotation speed setting means 14 to calculate the target rotation speed NE / CWU of the internal combustion engine 1 (STEP 11-4). In this case, the target rotation speed setting means 14 calculates the target rotation speed NE / CWU by the following equation (1).

NE / CWU = NOBJ + NECPIS- [K / NERED. (T / CWU-T / CPIS)] (1) Here, NOBJ in the formula (1) is a predetermined value shown in the lower part of FIG. Of idling speed (target speed during idling operation), and the term (NOBJ + NECPIS) indicates the set speed that is higher than the idling speed NOBJ by a predetermined amount NECPIS. In addition, (T /
CWU-T / CPIS), that is, the difference between the CWU elapsed time T / CWU and the value of the parameter T / CPIS, the value of the retard correction propriety flag F / NEFB is "0", the above STEP11-
By the process of 3, (T / CWU-T / CPIS) becomes 0 (at this time, NE / CWU = NOBJ + NECPIS = set speed), but the value of the delay angle correction enable / disable flag F / NEFB becomes "0". From the time when the value is changed from "1" to "1" (at this time, the rotational speed NE of the internal combustion engine 1 is set to the set rotational speed (NOBJ + NE
CPIS) and the elapsed time from). Further, K / NERED in the square brackets is the target rotation speed NE / CWU as described above with reference to FIG.
It is a predetermined coefficient (> 0) that defines the degree of decrease (slope) when decreasing from BJ + NECPIS) toward the idling speed NOBJ.

When obtaining the target revolution speed NE / CWU by the equation (1), the lower limit of the target revolution speed NE / CWU is set to the idling revolution speed NOBJ, and the calculation result on the right side of the equation (1) is When it becomes lower than the idling speed NOBJ, the target speed NE / CWU is thereafter set to the idling speed NOBJ.
Fixed to.

After the target engine speed NE / CWU is obtained by the target engine speed setting means 14 in this way, the ignition timing control means 15 detects the target rotational speed NE of the engine speed NE of the present internal combustion engine 1 and the target engine speed NE. Compared with / CWU (STEP 11-5),
If NE <NE / CWU, the process proceeds to STEP 11-7. However, if NE ≧ NE / CWU, after setting the value of the retard correction propriety flag F / NEFB to “1”. (STEP1
1-6), and shifts to the processing of STEP 11-7.

In this case, when the value of the retard correction propriety flag F / NEFB is "0", the target rotational speed NE / CWU calculated in STEP 11-4 is the set rotational speed (NOBJ +
Since it is NECPIS), the value of the retard correction propriety flag F / NEFB is changed from "0" to "1" when the rotation speed NE of the internal combustion engine 1 rises to the set rotation (NOBJ + NECPIS). After this change, that is, after the rotation speed NE of the internal combustion engine 1 rises to the set rotation speed (NOBJ + NECPIS), the target rotation speed NE calculated in STEP 11-4 is obtained.
/ CWU is the set speed (NOBJ + NE
CPIS) gradually decreases from idling speed NOBJ to a predetermined degree, and the idling speed
After reducing to NOBJ, the target speed NE / CWU will be maintained at the idling speed NOBJ. This is a form of temporal change of the target engine speed NE / CWU indicated by the broken line in the lower part of FIG.

Next, at STEP 11-7, the ignition timing control means 15 determines the current value of the retard correction propriety flag F / NEFB, and when F / NEFB = 1, that is, the rotation speed NE of the internal combustion engine 1. Is a state after the point where the set speed (NOBJ + NECPIS) is reached, the integral term I / calculated when the retard correction amount IG / CPID (n) is obtained by PI control in the previous control cycle. The value of IGCWU (n-1) is stored as the value of the parameter I / IGX (STEP 11-8). further,
The ignition timing control means 15 has a proportional term P / IGCWU (n) and an integral term I / IGCWU (n) for obtaining the retard correction amount IG / CPID (n) in the current control cycle by PI control, respectively.
Calculated by the following equations (2) and (3) based on the deviation (NE / CWU-NE) between the current target speed NE / CWU and the detection of the speed NE, P / IGCWU (n) = IGCWU • (NE / CWU-NE) …… (2) I / IGCWU (n) ＝ KIIGCWU ・ (NE / CWU−NE) ＋ I / IGCWU (n-1) …… (3) Furthermore, their proportional term P / IGCWU (n ) And the integral term I / IGCWU
The retard correction amount IG / CPID (n) in the current control cycle is calculated by adding (n) as in the following equation (4) ((S
TEP 11-9). The KPIGCW of the above formulas (2) and (3)
U and KIIGCWU are predetermined gain coefficients of the proportional term and the integral term, respectively.

IG / CPID (n) = P / IGCWU (n) + I / IGCWU (n) (4) Further, the ignition timing control means 15 controls the retard correction amount IG / CPID obtained in STEP 11-9. Limit processing for limiting the upper and lower limits is performed (STEP 11-10), and the processing for calculating the retard correction amount IG / CPID in the current control cycle is ended.

In addition, at the judgment of STEP 11-7, F / NEFB
= 0, that is, when the rotational speed NE of the internal combustion engine 1 has not yet reached the set rotational speed (NOBJ + NECPIS), the retard correction amount IG / CPID (n) in the present control cycle
Also, the value of the integral term I / IGCWU (n) is set to "0" (STEP 11-11), and the calculation process of the retard correction amount IG / CPID in the current control cycle is ended.

The retard correction amount IG / CPID calculated in STEP 11-9 as described above is set to the normal ignition timing.
By adding to IGBASE, the ignition timing is corrected to the retard side, and the value of the retard correction amount IG / CPID is basically a negative value. That is, the rotational speed of the internal combustion engine 1 is controlled by increasing the intake air amount by the intake air amount control means 13.
Since NE tends to increase with respect to the idling speed NOBJ, the speed NE of the internal combustion engine 1 is made to converge to the target speed NE / CWU, in other words, their deviation (NE / CWU-
PI control (feedback control) to eliminate NE)
The retard correction amount IG / CPID calculated by
The above-mentioned normal ignition timing IGBA
SE is corrected on the retard side (negative side of the ignition timing).
As a result, in the CWU mode, the retard correction amount IG / CPID is calculated in the form shown by the broken line in the middle of FIG. In FIG. 2, the lever of the automatic transmission (not shown) is changed from the N range (neutral range) to the D range (drive range) during the CWU mode, so the load of the internal combustion engine 1 is slightly increased. , The rotational speed NE slightly drops from the idling rotational speed NOBJ, and as a result, the magnitude (absolute value) of the retard correction amount IG / CPID after changing the transmission lever range becomes smaller than before the change. There is.

On the other hand, in the judgment of STEP 11-1, C
When the WU enable / disable flag F / CWUON = 0 (in the normal mode), the ignition timing control means 15 determines whether or not the current retard correction amount IG / CPID is equal to or greater than “0” ( ST
EP11-12). In this case, the current retard correction amount IG / CPI
If D is not equal to or greater than "0" (IG / CPID <0), the system operation mode immediately after shifting from the CWU mode in which the retard correction amount IG / CPID is calculated in STEP 11-9 to the normal mode. In this case, the ignition timing control means 15 sets the retard correction amount IG / CPID (n) in the present control cycle to the retard correction amount IG / CPID (n-1) in the previous control cycle. Predetermined value for DIG / CPI (>
0) is added (STEP 10-12). That is, the retard correction amount IG / CPID is set to a predetermined value for each control cycle.
DIG / CPI is gradually returned to the advance side. At this time, the upper limit value of the retard correction amount IG / CPID is set to “0”, and IG / CPID (n-1) +
If the calculation result of DIG / CPI becomes larger than "0", the retard correction amount IG / CPID (n) in this control cycle
Is set to "0".

[0111] In addition, IG / C is determined by the judgment of STEP 11-12.
When PID ≧ 0, that is, the above STEP 11-9
When the operation mode becomes the normal mode without the calculation of the retard correction amount IG / CPID in step S11, or after the CWU mode is switched to the normal mode, the delay correction amount is finally determined by the processing of STEP 11-13. When IG / CPID is returned to "0", the integral term I / IGCWU and the delay angle correction availability flag F /
Each value of NEFB, parameter T / CPIS, and target speed NE / CWU is cleared to “0” (STEP 10-13).

Returning to FIG. 10, as described above, the retard correction amount
After calculating the IG / CPID, the ignition timing control means 15
Basic value IGMAP of ignition timing obtained in STEP 10-1
And the correction value IGHK obtained in STEP 10-2 and ST
The retard correction amount IG / CPID obtained in EP10-3 is added, in other words, the normal ignition timing IGBASE (= IGMAP +
IGHK) is added to the retard correction amount IG / CPID to obtain the ignition timing command value IGLOG in the present control cycle (STEP 10-4). The ignition timing command value IGLOG thus obtained (more accurately, the ignition timing command value IGLOG obtained when the retard correction propriety flag F / NEFB is set to "1") is The rotational speed NE of the internal combustion engine 1 is set to the target rotational speed NE / C by PI control (feedback control).
It was decided to converge on WU.

Next, the ignition timing control means 15 sets the command value IGLOG of the ignition timing to the internal combustion engine 1 (including the ignition device 10).
Of the final ignition timing is determined by carrying out a limit process for limiting the value within an allowable range for normal operation of the engine and a process of setting the increase correction flag F / THODEC as follows (STEP 10-5). ).

That is, referring to the flowchart of FIG. 12, the ignition timing control means 15 first sets the retard side allowable limit value IGLGG which is the limit value on the retard side of the allowable range of the ignition timing to the current engine temperature TW. It is determined using a data table according to the above (STEP 12-1). Next, the ignition timing control means 15 sets a predetermined threshold value IGX (see FIG. 13) set to the advance side by a predetermined amount with respect to the retard side allowable limit value IGLGG.
Ignition timing command value IG determined in STEP 10-4
Compare with LOG (STEP12-2). At this time, IG
If LOG ≧ IGX and the command value IGLOG is on the advance side of the threshold value IGX (including the case of IGLOG = IGX), the above S
The value of the increase correction flag F / THODEC used in the determination process of TEP6-3 (see FIG. 6) is set to "0" (STE
P12-3), IGLOG <IGX and the command value IGLOG is the threshold value IG.
If it is on the delay side of X, the increase correction flag F /
Set the value of THODEC to "1" (STEP12-
4).

As a result, in this control cycle, the ignition timing command value IG determined in STEP 10-4 is determined.
When LOG is on the advance side of the threshold value IGX, in the process of FIG. 6 for obtaining the throttle opening command value THO / CWU in the CWU mode in the next control cycle, the throttle correction amount THO / DEC is kept at the previous value. Also,
Ignition timing command value IGLOG determined in STEP 10-4
Is on the retard side of the threshold value IGX, the throttle correction amount is determined by the processing of FIG. 6 in the next control cycle.
THO / DEC is corrected by the unit correction value d / THODEC to the side where the throttle opening is decreased.

After setting the value of the increase correction flag F / THODEC in this way, the ignition timing control means 15 determines in STEP10-
STEP12 of the ignition timing command value IGLOG determined in 4
-1 compared to the retard side allowable limit value IGLGG (ST
EP12-5), the command value IGLOG is the retard side allowable limit value IGLG
When it is on the advance side of G (when IGLOG ≧ IGLGG),
That is, when the command value IGLOG is within the allowable range of the ignition timing, the processing of FIG. 10 is terminated (the final ignition timing command value IGLOG is set to the value determined in STEP 10-4). On the other hand, when the command value IGLOG is on the retard side of the retard side allowable limit value IGLGG and deviates from the allowable range (IGLOG <
IGLGG), the final ignition timing command value IGLOG
Is forcibly limited to the retard limit side allowable limit value IGLGG (STEP
12-6), and further, the current value I / IGCWU (n) of the integral term in the PI control is set to the parameter I / IG in STEP 11-8.
The previous value I / IGCWU (n-1) stored as the IGX value is forcibly set (STEP 12-7). This makes PI
The value of the integral term I / IGCWU in control is STEP10-4.
When the command value IGLOG of the ignition timing determined in step 1 is on the retard side of the retard side allowable limit value IGLGG, the current value (the value in the previous control cycle) is held.

The controller 2 which has determined the final ignition timing command value IGLOG by the ignition timing control means 15 as described above, is controlled by the ignition timing control means 15.
G is instructed to the ignition device 10, at which time the ignition device 1
0 ignites the internal combustion engine 1 in accordance with the designated ignition timing IGLOG.

By controlling the ignition timing described above, C
In the WU mode, when the engine speed NE reaches the set engine speed (NOBJ + NECPIS) after the internal combustion engine 1 is started, the target engine speed NE / CWU set as described above (this finally becomes the idling engine speed NOBJ The ignition timing retard correction amount IG / CPID is obtained by PI control so that the rotational speed NE of the internal combustion engine 1 is converged.
The internal combustion engine 1 is ignited in accordance with the ignition timing command value IGLOG corrected by. That is, at the ignition timing of the internal combustion engine 1, the rotational speed NE of the internal combustion engine 1 is equal to the target rotational speed NE.
/ CWU to converge (finally idling speed
Feedback control is performed so that it converges to NOBJ.

At this time, the intake air amount of the internal combustion engine 1 is increased as compared with the normal idling operation as described above, and the rotational speed NE of the internal combustion engine 1 tends to increase with respect to the idling rotational speed NOBJ. As a result, the retard correction amount IG / PID becomes the correction amount on the retard side of the ignition timing (IG / PID <0) as shown by the broken line in the middle of FIG. As indicated by the solid line in the middle of 2, the control is performed on the retard side.

When the operation mode of the system shifts from the CWU mode to the normal mode (when the CWU mode is released) by operating the accelerator pedal while the internal combustion engine 1 is operating in the CWU mode. Gradually decreases the magnitude (absolute value) of the retard correction amount IG / PID obtained in the CWU mode, as shown in the right part of the middle part of FIG. 2, and finally becomes “0”. Therefore, the ignition timing IGLOG gradually returns to the normal ignition timing IGNASE on the advance side after the CWU mode is released.

By the operation of the system of the present embodiment described above, the intake air amount increase control of the internal combustion engine 1 and the ignition timing retard control are performed in the CWU mode after the internal combustion engine 1 is started. The calorific value of the internal combustion engine 1 becomes larger than that during the normal idling operation, and as a result, the temperature of the exhaust gas of the internal combustion engine 1 becomes high, and the temperature of the catalyst device 3 rapidly rises, The device 3 is activated early. As a result, the required purification capacity of the catalyst device 3 after the start of the internal combustion engine 1 can be secured at an early stage,
The exhaust performance can be improved.

In this case, in the initial stage of increasing the intake air amount, the intake air amount is gradually increased by gradually increasing the throttle opening, so that the rotational speed NE of the internal combustion engine 1 immediately after the start is smoothly increased. You can raise it. Further, when a certain amount of time has passed after the start of increasing the intake air amount (time t2 in FIG. 9), the throttle opening (more specifically, the basic value THO /
The basic throttle opening (= THO / CWU · KM / CWU) determined by CWU and basic value correction coefficient KM / CWU is gradually decreased with the passage of time in the form shown in the timetable of FIG. Basically, it is possible to prevent the rotational speed NE from increasing due to the decrease in friction of each part of the internal combustion engine 1 without correcting the ignition timing to the retard side more than necessary.

Then, in this case, the basic value THO / CTBL of the throttle opening (see FIG. 7) is set according to the engine temperature TW, and particularly in the high temperature region of the engine temperature TW, the basic value THO / CTBL is set.
To suppress the increase of the intake air amount to a lower value, the internal combustion engine 1 in the CWU mode in which the heat generation amount increases
It is possible to reduce the burden of.

Further, in controlling the ignition timing to the retard side in the CWU mode, the internal combustion engine 1 is set to a set rotational speed (NOBJ + NECPIS) higher than the idling rotational speed NOBJ which is the final target value of the rotational speed NE. Engine 1 speed NE
When the ignition timing is retarded, the target rotation speed NE / CWU is not immediately set to the idling rotation speed NOBJ, but rather the target rotation speed NE / CWU is set to the target rotation speed NEBJ.
/ CWU is set while gradually changing from the set speed (NOBJ + NECPIS) to the idling speed NOBJ, so sudden changes in the ignition timing to the retard side can be avoided. As a result, a situation in which the engine speed NE of the internal combustion engine 1 fluctuates significantly or becomes too low in the initial stage of starting the ignition timing control is eliminated, and the internal combustion engine 1 is operated stably. The rotation speed NE
Can be converged to the required idling speed NOBJ, and the purification performance of the exhaust gas by the purification device 3 can be stably ensured. In particular, in this embodiment,
As described above, when the ignition timing is feedback-controlled by the PI control so that the engine speed NE of the internal combustion engine 1 converges to the target engine speed NE / CWU (the retard angle correction availability flag F /
NEFB is set to "1"), STEP10-
The command value IGLOG of the ignition timing obtained in 4 is the threshold value IGX
Throttle opening THO
Is the basic throttle opening (= THO / CWU · KM / CWU) determined by the basic value THO / CWU and the basic value correction coefficient KM / CWU.
To the decreasing side and the increasing amount of the intake air amount is corrected to the decreasing side, so that there is an effect as will be described with reference to FIG. In addition, in the following description, in the state where the delay angle correction enable / disable flag F / NEFB is set to "1", STEP10
The command value IGLOG of the ignition timing obtained at -4 is called the feedback command value IGLOG. Further, FIG. 13 shows the changes in the rotational speed NE (actual rotational speed) of the internal combustion engine 1, the throttle opening THO, and the ignition timing feedback command value IGLOG with the solid lines in the upper, middle, and lower diagrams, respectively. It is shown.

That is, the manner in which the friction of each part of the internal combustion engine 1 is reduced as the internal combustion engine 1 warms up depends not only on the engine temperature TW but also on the influence of various factors such as the lubricating oil amount and the lubricating oil temperature. As described above, the throttle opening TH corresponding to the increase of the intake air amount in the form shown in the time table of FIG. 9 as described above.
In some cases, the friction may be reduced at a timing earlier than the timing of starting the reduction of O (time t2 in FIG. 9), or the friction may be significantly reduced as compared with the normal case. In this case, throttle opening
THO is the basic value THO / CWU and basic value correction factor KM / CWU
Basic throttle opening determined by (= THO / CWU ・ KM / C
For example, the rotation speed NE of the internal combustion engine 1 tends to increase with respect to the target rotation speed NE / CWU as shown in part A of the upper part of FIG. Also, with this,
The ignition timing feedback command value IGLOG is shown in FIG.
As shown in part B of the lower figure, the retard side allowable limit value IG
If the engine speed approaches the LGG and the upward trend of the rotational speed NE continues (see the phantom line a in the upper diagram of FIG. 13), finally, the value becomes on the retard side rather than the retard side allowable limit value IGLGG. It changes (see phantom line b in the lower diagram of FIG. 13). Then, in this way, the ignition timing feedback command value IGLO
G, that is, the rotational speed NE of the internal combustion engine 1 is the target rotational speed NE / CWU
Ignition timing command value IGLOG
However, when the value becomes on the retard side of the retard side allowable limit value IGLGG, the ignition timing that the controller 2 actually instructs the ignition device 10 is delayed as described above in order to ensure the normal operation of the internal combustion engine 1. Although it is limited to the corner-side allowable limit value IGLGG, in such a state, the rising tendency of the rotational speed NE cannot be suppressed, and the rotational speed NE is the target as shown by the phantom line a in the upper diagram of FIG. The number of revolutions NE / CWU increases greatly.

However, in the present embodiment, when the feedback command value IGLOG of the ignition timing is on the retard side of the threshold value IGX set slightly on the advance side of the retard side allowable limit value IGLGG, the state continues. As long as throttle opening THO
For each control cycle, the basic throttle opening (= THO / CWU and basic value correction coefficient KM / CWU)
THO / CWU · KM / CWU) by the unit correction value d / THODEC (see part C in the middle diagram of FIG. 13). In other words, the basic value THO / CWU and the basic value correction coefficient KM / C
The basic increase amount of the intake air amount defined by WU is corrected to the decreasing side by an amount corresponding to the unit correction value d / THODEC of the throttle opening. Further, in this case, the unit correction value d / THODEC of the throttle opening is set according to the engine temperature TW (the warm-up state of the internal combustion engine 1) when the internal combustion engine 1 is started, and therefore the friction of the internal combustion engine 1 is reduced. The amount of increase of the intake air amount can be corrected to the decreasing side in a form adapted to.

Therefore, the upward tendency of the rotational speed NE can be suppressed by the correction of the increase amount of the intake air amount to the decrease side. As a result, the ignition timing feedback command value IG
After LOG changes to the retard side with respect to the threshold value IGX, further change to the retard side is suppressed, and basically, as shown in part D of the lower diagram of FIG. It will return to the advance side without changing to the retard side up to IGLGG. In this case, the throttle opening THO that regulates the increase of the intake air amount is the basic throttle opening (= THO / CWU · KM / CWU) determined by the basic value THO / CWU and the basic value correction coefficient KM / CWU. ) Unit correction value d / THOD
Since the EC is gradually reduced, the increase of the intake air amount is gradually corrected to the decreasing side. Therefore, the command value IGLOG of the ignition timing, which is determined so as to converge the rotational speed NE to the target rotational speed NE / CWU, does not suddenly change.

Therefore, the ignition timing feedback command value IGLOG, which is determined so as to converge the rotational speed NE of the internal combustion engine 1 to the target rotational speed NE / CWU, is basically larger than the retard side allowable limit value IGLGG. The ignition device 10 is operated in accordance with the feedback command value IGLOG without causing any sudden change while being within the advance side, and the rotation speed NE of the internal combustion engine 1 is stably converged to the target rotation speed NE / CWU. Can be made.

Further, in the present embodiment, when the feedback command value IGLOG of the ignition timing reaches the threshold IGX in the process of returning from the value on the retard side to the advance side of the threshold IGX as described above, Throttle correction amount THO / DEC (This is the unit correction value d / THODEC for each control cycle from the time when the feedback command value of the ignition timing shifts to the retard side from the threshold value IGX until it returns to the threshold value IGX. The accumulated value) is held at the current value (value determined in the previous control cycle). Therefore, the ignition timing command value IGLO
After reaching the threshold value IGX in the process of G returning to the advance side, the basic throttle opening (= THO / CW) unless the ignition timing command value IGLOG shifts to the retard side from the threshold value IGX again.
The throttle correction amount THO / DEC with respect to (U · KM / CWU) is maintained constant without further increase (see the portion E in the middle diagram of FIG. 13).

As a result, it is possible to avoid a situation in which the amount of increase in the intake air amount is unnecessarily reduced, the heat generation amount of the internal combustion engine 1 is reduced, and the activation of the catalyst device 3 is delayed.

Further, in the present embodiment, the feedback command value IG of the ignition timing is set by the sudden decrease of the load of the internal combustion engine 1 or the like.
When LOG exceeds the retard side allowable limit value IGLGG and changes to the retard side, the integral term I /
Holding the value of IGCWU has an effect as will be described with reference to FIG. Note that FIG. 14 shows the changes in the rotational speed NE (actual rotational speed) of the internal combustion engine 1, the throttle opening THO, and the ignition timing feedback command value IGLOG with the solid lines in the upper, middle, and lower diagrams, respectively. It is shown.

That is, for example, when the automatic transmission connected to the internal combustion engine 1 is changed from the D range to the N range in a state where the friction of the internal combustion engine 1 is relatively greatly reduced, the load of the internal combustion engine 1 is rapidly reduced. Then, the increasing tendency of the rotational speed NE appears strongly (refer to the portion F in the upper diagram of FIG. 14), and the correction to the decreasing side by the increase amount of the intake air amount as described above immediately causes the increase of the rotational speed NE. It is not possible to suppress the rising tendency, and the feedback command value IGLOG of the ignition timing becomes the retard side allowable limit value IGLG.
There may be a sudden change to the retard side exceeding G (see the G portion in the lower diagram of FIG. 14).

In such a case, even if the feedback command value IGLOG exceeds the retard side allowable limit value IGLGG on the retard side, the calculation / update of the integral term I / IGCWU in PI control is continued. Then, since the integral term I / IGCWU is the temporal integration of the deviation (NE−NE / CWU) between the rotational speed NE and the target rotational speed NE / CWU, its value increases,
Therefore, the feedback command value IGLOG obtained by using the value of the integral term I / IGCWU is a value larger on the retard side than the retard side allowable limit value IGLGG as shown by a virtual line c in the lower diagram of FIG. It will become. Therefore, thereafter, as the correction of the throttle opening THO decreases as described above (see the middle diagram of FIG. 14), the increasing tendency of the rotational speed NE is suppressed, and the rotational speed NE tends to decrease. However, the feedback command value IGLOG is advanced beyond the retard side allowable limit value IGLGG as shown by a virtual line c in the lower diagram of FIG. It takes time to come back to the side. As a result, it is not possible to quickly suppress the downward trend of the rotational speed NE, and the rotational speed NE causes a large drop with respect to the target rotational speed NE / CWU as shown by a virtual line d in the upper diagram of FIG. It is easy to store.

However, in the present embodiment, when the feedback command value IGLOG exceeds the retard side allowable limit value IGLGG on the retard side, the integral term I as shown by the I portion of the dashed line in the lower diagram of FIG. Since / IGCWU is held at the value at that time, the feedback command value IGLOG is the deviation (NE−NE / CWU) between the rotation speed NE and the target rotation speed NE / CWU for each control cycle.
Only the proportional term P / IGCWU (see the broken line in the lower diagram of FIG. 14) proportional to ## EQU1 ## changes as shown in the J portion of the lower diagram of FIG. 14 (in this J portion, the internal combustion engine 1
The actual ignition timing of is limited to the retard side allowable limit value IGLGG). Therefore, the feedback command value IGLOG does not change greatly from the retard side allowable limit value IGLGG to the retard side. Therefore, thereafter, as the correction of the throttle opening THO decreases as described above (see the middle diagram of FIG. 14), the increasing tendency of the rotational speed NE is suppressed and the rotational speed NE tends to decrease. When it comes to (see H part of the upper diagram of FIG. 14), the feedback command value
IGLOG quickly returns to the advance side of the retard side allowable limit value or more, as indicated by the J portion in the lower part of FIG. As a result,
The actual ignition timing of the internal combustion engine 1 can now be promptly controlled in accordance with the feedback command value IGLOG on the advance side over the retard side allowable limit value, and the downward tendency of the rotational speed NE can be quickly suppressed. , It becomes possible to converge to the target rotational speed NE / CWU as shown by K in the upper diagram of FIG.

As described above, in the system of the present embodiment, when the ignition timing is feedback-controlled so that the rotation speed NE of the internal combustion engine 1 converges to the target rotation speed NE / CWU, various conditions are satisfied. The convergence and stability of the control can be accurately ensured.

In addition, in the system of this embodiment, the internal combustion engine 1 can be used when the vehicle is running or when the air conditioner is operated.
Depending on the situation, the load must be driven, or the engine speed NE and engine temperature TW of the internal combustion engine 1 are too high or too low, and the operating time of the internal combustion engine 1 in the CWU mode is a predetermined time limit TCWULMT. CWU mode is canceled or the system does not operate in the CWU mode, the required drive performance of the load by the internal combustion engine 1 can be ensured and the internal combustion engine 1
It is possible to avoid an excessive burden on the.

Then, in this case, when the CWU mode is released, the increase control of the intake air amount of the internal combustion engine 1 is immediately released and the opening of the throttle valve is made to correspond to the operation amount of the accelerator pedal. At the same time, since the ignition timing is gradually returned to the original advance side, the running of the vehicle (drive of the load by the internal combustion engine 1) can be started by the smooth operation of the internal combustion engine 1 according to the operation of the accelerator pedal. .

Further, in the control of the ignition timing to the retard side in the CWU mode, the intake air amount is increased, and the rotation speed NE of the internal combustion engine 1 obtained as a result of the increase is set to the target rotation speed NE / CWU. Is performed by correcting the ignition timing so that the intake air is not affected by the delay in the change in the intake air amount due to the control of the opening degree of the throttle valve. Retardation correction amount IG
/ PID controls the ignition timing to the retard side.

Therefore, the intake air amount increasing control for activating the catalyst device 3 early and the ignition timing retarding control can be independently performed. The control to the retard side can be performed by the feedback control focusing only on the rotational speed NE of the internal combustion engine 1. Therefore, the system of the present embodiment can be simplified while ensuring necessary controllability. be able to.

In the present embodiment described above, the target engine speed NE / CWU (the target engine speed from the time when the engine speed NE reaches the set engine speed (NOBJ + NECPIS)) during the control on the retard side of the ignition timing. ) Was changed linearly from the set speed (NOBJ + NECPIS) toward the idling speed NOBJ with a certain degree of decrease, but the target speed NE / CWU was changed from the set speed (NOBJ + NECPIS) to the idling speed It may be changed in other forms, such as changing in a curve toward the number NOBJ.

Further, in this embodiment, the retard correction amount IG / PID of the ignition timing for converging the rotational speed NE of the internal combustion engine 1 to the target rotational speed NE / CWU is obtained by using PI control. However, the retardation correction amount IG / PID may be obtained using PID control in which not only the proportional term and the integral term but also the derivative term is added.

Further, in this embodiment, the intake air amount is controlled by the throttle actuator 12, but the intake air amount is bypassed by controlling the intake air amount by interlocking the throttle valve with a normal accelerator pedal. It may be performed by controlling the flow rate of the bypass flow path. In this case, the flow rate control valve that controls the flow rate of the bypass flow path may be provided with a flow rate characteristic that can secure the amount of intake air required in this embodiment. Further, the opening degree of the flow control valve is the opening degree TH of the throttle valve described in the present embodiment.
It can be calculated similarly to the value of O.

[Brief description of drawings]

FIG. 1 is a system configuration diagram of an embodiment of a control device for an internal combustion engine of the present invention.

FIG. 2 is a diagram for explaining an outline of operation of the system of FIG.

FIG. 3 is a flowchart for explaining control processing of the system of FIG.

FIG. 4 is a flowchart for explaining a control process of the system of FIG.

5 is a flowchart for explaining control processing of the system in FIG.

FIG. 6 is a flowchart for explaining control processing of the system of FIG.

7 is a diagram showing a data table used in the control processing of the flowchart of FIG.

8 is a diagram showing a data table used in the control processing of the flowchart of FIG.

9 is a diagram showing a data table used in the control processing of the flowchart of FIG.

10 is a flowchart for explaining control processing of the system of FIG.

FIG. 11 is a flowchart for explaining control processing of the system of FIG.

FIG. 12 is a flowchart for explaining control processing of the system of FIG.

FIG. 13 is a diagram for explaining the operation of the control processing of the system of FIG.

FIG. 14 is a diagram for explaining the operation of the control processing of the system of FIG.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Internal combustion engine, 3 ... Catalyst device, 13 ... Intake air amount control means, 14 ... Target rotation speed setting means, 15 ... Ignition timing control means.

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification symbol FI F02D 43/00 310 F02P 5/15 EK (72) Inventor Yoshihisa Iwaki 1-4-1 Chuo Wako, Saitama Prefecture Honda Co., Ltd. Inside Technical Research Institute (72) Inventor Tadashi Sato 1-4-1 Chuo, Wako-shi, Saitama Inside Corporate Research Laboratories, Inc. (56) Reference JP-A-3-9056 (JP, A) JP-A-2-185674 ( JP, JP-A-63-186948 (JP, A) JP-A-11-50937 (JP, A) JP-A-2-161153 (JP, A) JP-A-4-128538 (JP, A) JP-A Flat 10-299631 (JP, A) (58) Fields investigated (Int.Cl. ⁷ , DB name) F02P 5/145-5/155 F02D 41/00-41/40 F02D 43/00-43/04 F02D 45/00

Claims (10)

(57) [Claims] 1. A system for performing early activation of the purification device after starting an internal combustion engine that discharges exhaust gas through the purification device.
During idling operation in operation mode, the intake air amount of the internal combustion engine is idled in modes other than the above operation modes.
Intake air amount control means for increasing the intake air amount by a predetermined increase from the intake air amount during operation, and after the intake air amount starts increasing, the internal combustion engine rotation speed is made to converge to a predetermined target rotation speed. Ignition timing control means for generating a command value of the ignition timing by feedback control processing, and controlling the ignition timing of the internal combustion engine based on the generated command value of the ignition timing to correct the ignition timing to the retard side. In a control device for an internal combustion engine, the command value of the ignition timing generated by the ignition timing control means by the feedback control processing, the ignition timing of the ignition timing within a predetermined allowable range of the ignition timing capable of normal operation of the internal combustion engine. The intake air amount control means is provided with means for correcting the intake air amount increase amount to the intake air amount decrease side when the value becomes on the delay angle side with respect to the predetermined threshold value set on the retard angle side. A control device for an internal combustion engine, characterized in that 2. The intake air amount control means is characterized in that the intake air is controlled in a state in which a command value of the ignition timing generated by the ignition timing control means by the feedback control processing is a value on the retard side of the predetermined threshold value. 2. The control device for an internal combustion engine according to claim 1, wherein the correction amount to the decreasing side of the increase amount of the amount is gradually increased. 3. The intake air amount control means sets the correction amount according to the warm-up state of the internal combustion engine when gradually increasing the correction amount to the decreasing side of the increase amount of the intake air amount. 3. The control device for an internal combustion engine according to claim 2, wherein the control amount is increased by a predetermined amount for each predetermined control cycle. 4. The command for the ignition timing generated by the ignition timing control means by the feedback control processing when the intake air amount control means corrects the increase amount of the intake air amount toward the decrease side. 4. The internal combustion engine according to claim 2, wherein when the value changes to the advance side from the threshold value, the correction amount to the decrease side of the increase amount of the intake air amount is held at the current correction amount. Control device. 5. The internal combustion engine according to claim 1, wherein the threshold value is set to an advance side with respect to a retard side limit value of the allowable range of the ignition timing. Control device. 6. The ignition timing control means successively generates a command value of the ignition timing of the internal combustion engine by using proportional integral control as the feedback control process, and the generated command value of the ignition timing is the ignition timing. When the value on the retard side exceeds the retard side limit value of the allowable range of, the ignition timing of the internal combustion engine is controlled by the retard side limit value, and the value of the integral term in the proportional integral control is currently set. 6. The control device for an internal combustion engine according to claim 1, wherein the control device holds the value of. 7. After the rotational speed of the internal combustion engine reaches a predetermined set rotational speed that is higher than a predetermined idling rotational speed after the intake air amount control means starts increasing control of the intake air amount, 7. The internal combustion engine control according to claim 1, further comprising target rotation speed setting means for setting the target rotation speed while changing the target rotation speed from the set rotation speed toward the idling rotation speed. apparatus. 8. The intake air amount control means sets the increase amount of the increase amount of the intake air amount in a non-corrected state according to the engine temperature of the internal combustion engine. 5. A control device for an internal combustion engine according to any one of 1. 9. The intake air amount control means controls the increase amount of the increase amount of the intake air amount in a non-corrected state so as to gradually increase immediately after the internal combustion engine is started. A control device for an internal combustion engine according to any one of claims 1 to 8. 10. The intake air amount control means preliminarily adjusts the increased amount of the increased intake air amount in a non-corrected state after a predetermined time has elapsed from the start of the increased intake air amount control. The control device for an internal combustion engine according to any one of claims 1 to 9, characterized in that the control is performed so as to gradually decrease with a lapse of time in a predetermined form.