JP6758451B1 - Internal combustion engine control device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To realize early activation of a catalyst while ensuring stall resistance and drivability even for a vehicle having a large friction loss due to vehicle variation regardless of a driving state such as idle or off-idle. Until the catalyst reaches the light-off temperature, the target ignition timing for achieving the target torque during idle operation is retarded until the catalyst warm-up target ignition timing for early activation of the catalyst. As described above, the required exhaust heat conversion torque is increased and corrected by the required exhaust heat conversion torque correction value, and the intake amount according to the throttle opening is increased. When switching from idle operation to off-idle operation, the required exhaust heat conversion torque correction value is stored, and the required exhaust heat conversion torque is stored using the required exhaust heat conversion torque correction value stored even during off-idle operation. The calculation is performed to increase the intake amount due to the throttle opening and to delay the ignition by the increased torque increase regardless of the operating state of idle / off idle. [Selection diagram] Fig. 4

Description

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

Hazardous components in the exhaust gas of internal combustion engines are one of the major causes of air pollution. Therefore, a catalyst device that converts the harmful substance into a harmless substance is generally used. Since the catalyst device does not function sufficiently when the catalyst does not reach a predetermined temperature, when the catalyst is cold, harmful substances are discharged as they are without being treated. In order to solve such a problem, various catalyst warm-up controls for activating the catalyst at an early stage have been conventionally proposed, and examples of this type of control device include Patent Document 1, Patent Document 2, and Patent Document 1. A disclosure proposal is made in Document 3.

Patent Document 1 is a control device for an internal combustion engine that feedback-controls the ignition timing to the retard side so as to converge the ignition timing to the target rotation speed at idle while increasing the intake amount as the catalyst warm-up control as compared with the normal idle operation. It is about.
Further, Patent Document 2 sets the ignition timing as catalyst warm-up when the engine speed converges to the target speed during idle operation before the ignition timing is retarded to the target ignition timing due to variations among engines. It relates to a control device of an internal combustion engine that retards the ignition timing to the target ignition timing for the purpose and feedback-controls the intake amount to the increase side.
In both the disclosed techniques of Patent Document 1 or Patent Document 2, early activation of the catalyst is achieved by raising the temperature of the exhaust gas flowing to the catalyst due to the retardation of the ignition timing.

Further, Patent Document 3 retards the ignition timing as catalyst warm-up control, but when the amount of change or decrease in output torque exceeds a predetermined range, the engine system corrects the ignition timing to the advance side. It is about. This eliminates combustion failure or torque shortage when it is desired to increase the output torque during acceleration.

Japanese Unexamined Patent Publication No. 11-210608 Japanese Unexamined Patent Publication No. 2005-214072 Japanese Unexamined Patent Publication No. 08-218995

According to the control device for an internal combustion engine disclosed in Patent Document 1 or Patent Document 2, a target rotation speed during idle operation is set in advance, and the ignition timing or intake amount is feedback-controlled toward the target rotation speed. For example, when the vehicle is started by operating the accelerator pedal, the catalyst warm-up control is released and the internal combustion engine is controlled according to the normal operation of the accelerator pedal. In other words, when driving, drivability is prioritized over early activation of the catalyst so as not to cause acceleration failure.

Further, in Patent Document 2, both the variation in the friction loss of the engine itself and the required amount for raising the temperature of the exhaust heat flowing to the catalyst are collectively feedback-controlled by the intake amount, so that the catalyst warm-up control is performed. If the increase in the intake air amount is invalidated at the time of interruption or termination, if the friction loss varies to the larger side, the idle rotation due to insufficient output torque will decrease and drivability will deteriorate.

Further, according to the engine system disclosed in Patent Document 3, the ignition timing is corrected to the advance side in order to increase the output torque at the time of acceleration or the like so that the acceleration is not worse than the early activation of the catalyst during running. Priority is given to drivability.

That is, in the techniques of Patent Document 1, Patent Document 2, or Patent Document 3, when the ignition retard command is prioritized in order to activate the catalyst at an early stage, the rotation is reduced during idle operation or during running due to insufficient output torque. If the acceleration failure occurs and the ignition advance command is prioritized to secure the output torque, the temperature of the exhaust gas flowing to the catalyst will drop, and the time required to activate the catalyst will increase. There is a problem that the two factors that are in a trade-off relationship between the two factors cannot be compatible.

The present application discloses a technique for solving the above-mentioned problems, and stall resistance or a driver even for a vehicle having a large friction loss due to vehicle variation regardless of a driving state such as idle or off-idle. It is an object of the present invention to provide a control device for an internal combustion engine capable of realizing early activation of a catalyst while ensuring the ability.

The internal combustion engine control device disclosed in the present application includes a required shaft torque for intake control obtained from the accelerator opening, a preset loss torque, a rotation speed feedback amount during idle operation, and a requirement for early activation of the catalyst. A target throttle opening calculation means for calculating the target throttle opening based on the required combustion torque for intake control obtained from the required exhaust heat conversion torque obtained by converting the exhaust heat amount into torque.
The required retard angle from the MBT ignition timing in order to realize the required shaft torque for ignition control obtained from the accelerator opening, the loss torque, and the required combustion torque for ignition control obtained from the rotation speed feedback amount during idle operation. A target ignition timing calculation means that calculates the target ignition timing by calculating the amount,
If the target ignition timing is on the advance side of the catalyst warm-up target ignition timing that activates the catalyst early during the idle operation, the required exhaust heat conversion torque correction value is gradually increased to convert the required exhaust heat amount. The required exhaust heat conversion torque calculation means for increasing and correcting the torque,
With
When the target throttle opening is controlled to the open side and the idle operation is switched to the off-idle operation, the required exhaust heat conversion torque correction value is stored, and the requested exhaust heat conversion torque correction value is used. It is characterized by calculating the exhaust heat conversion torque.

According to the control device of the internal combustion engine disclosed in the present application, the catalyst can be used while ensuring stall resistance or drivability even for a vehicle having a large loss torque due to vehicle variation regardless of the operating state such as idle or off-idle. Early activation can be achieved.

It is a block diagram which shows typically the engine controlled by the control device of the internal combustion engine which concerns on Embodiment 1. FIG. It is a block diagram which shows the calculation means of the target ignition timing and the target throttle opening degree in the control device of the internal combustion engine which concerns on Embodiment 1. FIG. It is a block diagram which shows the calculation means of the required exhaust heat amount conversion torque in the control device of the internal combustion engine which concerns on Embodiment 1. FIG. FIG. 5 is a time chart diagram showing changes in ignition timing, throttle opening degree, and the like in the control device of the internal combustion engine according to the first embodiment. It is a figure which shows an example of the hardware of the control device of the internal combustion engine which concerns on Embodiment 1. FIG.

Hereinafter, preferred embodiments of the internal combustion engine control device according to the present application will be described with reference to the drawings.

Embodiment 1.
FIG. 1 is a configuration diagram schematically showing an engine controlled by a control device for an internal combustion engine according to a first embodiment. As the internal combustion engine in the present embodiment, an internal combustion engine of a vehicle equipped with a gasoline engine is assumed.
In FIG. 1, an electronically controlled throttle valve 2 that is electronically controlled to adjust the intake air flow rate is provided upstream of the intake system of the engine 1. Further, a throttle opening sensor 3 for measuring the opening degree of the electronically controlled throttle valve 2 is provided. Further, an air flow sensor 4 for measuring the intake air flow rate is provided upstream of the electronically controlled throttle valve 2, and the pressure in the surge tank 5 is applied to the engine 1 side downstream of the electronically controlled throttle valve 2. An intake pressure sensor 6 for measuring is provided. Both the air flow sensor 4 and the intake pressure sensor 6 may be provided, or only one of them may be provided.

Although not shown, an intake air temperature sensor that detects the temperature of the passing intake air of the electronically controlled throttle valve 2 is provided upstream of the electronically controlled throttle valve 2 or in the surge tank 5. An injector 7 for injecting fuel is provided in the intake passage downstream of the surge tank 5. The injector 7 may be provided so that it can be directly injected into the cylinder of the engine 1. Further, the engine 1 is provided with an ignition coil 8 and a spark plug 9 for igniting the air-fuel mixture in the cylinder of the engine 1, and also determines the rotation speed (hereinafter referred to as the rotation speed) or the crank angle position of the engine 1. A crank angle sensor 10 for detecting is provided. The crank angle sensor 10 detects the edge of the plate provided on the crankshaft, and detects the rotation speed of the engine 1 or the crank angle position.

An air-fuel ratio sensor 11 for measuring the air-fuel ratio of the exhaust gas is provided in the exhaust passage downstream of the engine 1, and a catalyst 12 for purifying the exhaust gas is further downstream. As the catalyst 12, for example, a three-way catalyst, a NOX storage catalyst, or the like is used. In order to purify the exhaust gas of any of the catalysts 12, it is necessary to raise the temperature to a temperature higher than the light-off temperature at which the purification ability begins to be exhibited.

Although not shown, the vehicle is provided with an accelerator pedal and a brake pedal, and is provided with an accelerator opening sensor for detecting the operation amount of the accelerator pedal and a brake sensor for detecting the operation of the brake pedal. As the brake sensor, a brake stroke sensor that detects the amount of operation of the brake pedal, a brake switch that detects the presence or absence of operation of the brake pedal, and the like are used.

Next, torque-based control, which is known as one of the control methods for the engine 1, will be briefly described.
In torque-based control, the intake air flow rate, fuel injection amount, ignition timing, etc. are controlled based on the magnitude of torque required for the engine. For example, a target value of torque to be output by the engine is calculated based on the accelerator opening degree or the number of revolutions, and the operating state of the engine is controlled so that this target torque can be obtained. Further, in a vehicle equipped with an external control system such as an automatic transmission, an auto cruise device, and a collision damage mitigation device, the output request from each external control system to the engine is converted into a torque value and unified in the engine control unit (ECU). It is controlled and the torque behavior of the engine is comprehensively controlled.

In the torque-based control in the present embodiment, it is assumed that two types of control having different responsiveness to each control operation amount, that is, high-speed response torque control and low-speed response torque control are performed. In the former high-speed response torque control, the torque is controlled by the ignition timing by operating the ignition coil 8 and the spark plug 9. Further, in the latter low-speed response torque control, the torque is controlled by the intake air flow rate by operating the electronically controlled throttle valve 2. Since these controls differ not only in torque responsiveness but also in the controllable torque output range, each control operation amount is coordinatedly adjusted according to the operating state of the engine or the running state of the vehicle.

In FIG. 2, in this torque-based control, the calculation means of the target ignition timing and the target throttle opening degree in the control device of the internal combustion engine according to the first embodiment will be described.
In FIG. 2, the ignition control required shaft torque calculation means 201 calculates the ignition control required shaft torque to be realized by controlling the operation amount of the ignition timing from the accelerator opening or the rotation speed (not shown), and is used for ignition control. It is sent to the required combustion torque calculation means 202. The shaft torque here indicates the moment of force on the crankshaft of the engine 1. Further, the combustion torque indicates a torque equivalent amount (pressure corresponding to the torque) expressed by the average effective pressure acting on the piston of the engine 1.

In addition to the ignition control required shaft torque, a loss torque which is a total value of various loss torques of the engine 1 is input to the ignition control required combustion torque calculating means 202. The loss torque includes friction loss torque equivalent to mechanical loss, pump loss torque equivalent to intake loss, auxiliary load torque equivalent to auxiliary load from a generator or air conditioner, and rotation speed feedback toward the target rotation speed during idle operation. Among the controls, the loss torque learning value stored and retained can be mentioned as the learning value of the machine difference variation.

Further, the rotation speed feedback amount in the rotation speed feedback control is also sent to the ignition control required combustion torque calculation means 202. The rotation speed feedback amount is a value corresponding to the torque of the rotation speed feedback amount (P term) by proportional control and the rotation speed feedback amount (I term) by integral control according to the deviation between the target rotation speed and the actual rotation speed. Given in. In the ignition control required combustion torque calculation means 202, the required combustion torque for ignition control to be realized is calculated by adding up these input information and controlling the operation amount of the ignition timing, and is sent to the target ignition timing calculation means 203. ..

Next, in the target ignition timing calculation means 203, the target ignition timing is calculated using the filling efficiency obtained from the rotation speed or the intake air flow rate (not shown) in addition to the required combustion torque for ignition control. Generally, when the rotation speed and the filling efficiency are constant, the combustion torque TQ generated in the engine 1 is approximated as a quadratic function of the ignition timing IG. More specifically, as shown in the following equation (1), MBT (Minimum Advance for Best Torque) is approximated by a quadratic function with the ignition timing B as the apex, and A, B, and C are the rotation speed and the filling efficiency. It is preset as a map of.
TQ = -A (B-IG) ² + C ... (1)
After calculating A, B, and C from the map according to the operating state of the engine, the target ignition timing for realizing the required combustion torque for ignition control is calculated from the relation of the equation (1). Here, as the characteristics of A, B, and C for each operating state, the higher the filling efficiency, the larger the C value corresponding to the combustion torque at the time of MBT, but A corresponding to the torque reduction coefficient according to the amount of retardation from the MBT. Since the value is also large, the amount of decrease in the combustion torque with respect to the amount of retardation from the MBT tends to be large during traveling when the filling efficiency is higher than during idle operation.

Subsequently, the intake control request shaft torque calculation means 204 has the same configuration as the ignition control request shaft torque calculation means 201, and is desired to be realized by controlling the operation amount of the throttle opening from the accelerator opening or the rotation speed (not shown). The intake control required shaft torque is calculated and sent to the intake control required combustion torque calculation means 205.

In addition to the intake control required shaft torque, the loss torque and the rotation speed feedback amount (term I) are input to the intake control required combustion torque calculation means 205. Regarding the rotation speed feedback amount (P term), there is a concern that the output torque or idle rotation speed may hunt in low-speed response torque control that controls the torque by the intake air flow rate, so it is input only under limited conditions such as engine stall relief. Therefore, it is not shown here. Further, the required exhaust heat conversion torque described later is also sent to the intake control required combustion torque calculation means 205, and the required intake control required combustion torque to be realized by adding up these input information and controlling the throttle opening operation amount. Is calculated and sent to the target throttle opening degree calculation means 206.

Next, in the target throttle opening degree calculating means 206, in addition to the required combustion torque for intake control, information indicating the operating state of the engine 1 such as the rotation speed, the filling efficiency, the intake manifold pressure, and the air-fuel ratio (not shown) is input. The target throttle opening is calculated. Specifically, the target filling efficiency for outputting the required combustion torque for intake control is calculated from the conversion coefficient correlated with the thermal efficiency of the engine 1 in the current operating state, and the throttle is set so as to achieve the target filling efficiency. The target throttle opening area is calculated using the front-rear pressure or the intake air temperature, and the target throttle opening is calculated from the characteristics of the electronically controlled throttle valve 2. Here, the intake delay from the electronically controlled throttle valve 2 to the cylinder is also corrected by using information such as the intake manifold pressure or the surge tank volume.

As shown in FIG. 2, the control operation amount of the catalyst warm-up control is only in the intake control required combustion torque calculation means 205 in the process of calculating the target throttle opening as shown in the calculation means of the target ignition timing and the target throttle opening. By adding the required exhaust heat conversion torque, the intake air flow rate is increased, and the ignition timing is delayed so as to realize the required shaft torque for ignition control at the target ignition timing.

Next, in FIG. 3, the calculation means of the required exhaust heat conversion torque in the control device of the internal combustion engine according to the first embodiment will be described.
The required exhaust heat conversion torque reference value calculation means 301 calculates the required exhaust heat conversion torque reference value based on a map centered on the filling efficiency and the cooling water temperature. This map uses a standard engine 1 to which the friction loss torque or auxiliary load torque is adapted, and actually retards the ignition timing from the required amount to raise the temperature of the catalyst, and the grid points of the map. It is adapted every time. When adapting this map, the catalyst warm-up target ignition timing, which is the required value for how far the ignition timing should be retarded for catalyst warm-up, is also measured, and the catalyst warm-up target ignition timing calculation means. In 302, the catalyst warm-up target ignition timing is calculated based on the map centered on the filling efficiency and the cooling water temperature. The target ignition timing for warming up the catalyst is set to the retard side within a range that does not cause misfire due to ignition retardation or high temperature enough to melt the catalyst.

Subsequently, the required exhaust heat conversion torque correction value calculation means 303 uses the catalyst warm-up target ignition timing and the target ignition timing calculated by the target ignition timing calculation means 203 of FIG. 2 as input information to convert the required exhaust heat amount. Calculate the torque correction value. Specifically, the required exhaust heat conversion torque correction value is gradually corrected to the increasing side so that the target ignition timing delays the ignition until the catalyst warm-up target ignition timing for early activation of the catalyst. Here, if the engine itself conforms to the map of the required exhaust heat conversion torque reference value, the target ignition timing and the catalyst warm-up target ignition timing are about the same value without increasing the required exhaust heat conversion torque correction value. However, in an engine with a large friction loss torque, the intake air flow rate is increased by the rotation speed feedback, and the target ignition timing is a catalyst based on the above equation (1) and the characteristics of A, B, and C for each operating state. Warm-up control The rotation speed during idle operation stabilizes on the advance side of the target ignition timing.

Next, the required exhaust heat conversion torque reference value and the required exhaust heat conversion torque correction value are input to the required exhaust heat conversion torque calculation means 304, and the required exhaust heat conversion torque is calculated by adding up the two torque information. Calculate. Here, the required exhaust heat conversion torque calculation means 304 is input with accelerator information that identifies whether the vehicle is idle or has the intention of traveling, and brake information that identifies whether the vehicle intends to brake by operating the brake during the operation. To. The input required exhaust heat conversion torque correction value allows the correction amount to be updated to the increase side during idle operation, but prohibits the update during driving or no-road racing operation state due to accelerator depression, etc., and is idle immediately before. Hold and store the value updated during operation. As a result, the intake air flow rate can be increased by using the required exhaust heat conversion torque for catalyst activation, which is updated at idle even during running, and the target ignition timing can achieve the required shaft torque for ignition control. Since the ignition timing can be delayed, early activation of the catalyst is realized while ensuring stall resistance or drivability even for vehicles with large loss torque due to vehicle variation regardless of driving conditions such as idle and off-idle. can do.

In addition, by gradually correcting the required exhaust heat conversion torque correction value to the increasing side during idle operation, if the target ignition timing is retarded to the catalyst warm-up target ignition timing, the required exhaust heat conversion torque correction value By stopping the update of and holding the value, unnecessary fluctuations in the throttle opening are suppressed and the stability of idle rotation is improved, while misfire due to excessive ignition timing or high temperature enough to melt the catalyst. Prevent becoming.

Further, in the required exhaust heat conversion torque calculation means 304, when the braking mode is entered by stepping on the brake during traveling, the required exhaust heat conversion torque is calculated in order to secure the negative pressure in the in-mani for braking. It is invalidated, and the addition of the required exhaust heat conversion torque by the required combustion torque calculating means 205 for intake control in FIG. 2 is prohibited. As a result, when there is an intention to decelerate, the output torque is reduced with priority given to safety, and the braking ability by the brake can be exhibited by securing the negative pressure in the intake manifold. In particular, it exerts a great effect of ensuring braking performance in an environment where the altitude is high and the atmospheric pressure is low.

Further, in the required exhaust heat conversion torque calculation means 304, when the braking mode is released by releasing the brake during traveling, the required exhaust heat conversion torque is set to the required exhaust heat conversion torque reference value in the current operating state. Then, the catalyst warm-up control is restarted by gradually increasing and correcting the sum of the required exhaust heat conversion torque correction values stored at idle. As a result, it is possible to realize drivability in which a sudden increase or decrease in torque during traveling is suppressed while realizing early activation of the catalyst.

Further, in the required exhaust heat conversion torque calculation means 304, after the catalyst reaches the light-off temperature, the required exhaust heat conversion torque is gradually reduced and corrected until the catalyst warm-up control becomes invalid. As a result, the catalyst warm-up control can be terminated without causing a sudden change in the operating state of the engine 1, so that the stall resistance during idle operation and the drivability during traveling are not impaired. Whether or not the catalyst has reached the light-off temperature is determined by a catalyst temperature sensor that measures the temperature of the catalyst (not shown in FIG. 1), or the integrated value of the intake air flow rate after the engine 1 is started. There are various means such as determining whether or not the accumulated amount exceeds a preset value.

Next, the behavior of the operating state of the engine and various control operation amounts when the control device of the internal combustion engine according to the first embodiment is applied will be described.
In FIG. 4, when the control device for the internal combustion engine according to the embodiment is applied, the vehicle speed Vs, the rotation speed Ne, the target ignition timing Igt, the rotation speed feedback amount (I term) TQfbi, and the rotation speed feedback amount (P term). It is a chart figure which showed the behavior of TQfbp, the required exhaust heat amount conversion torque TQwup, and the target throttle opening degree Tht by a solid line. Regarding the target ignition timing Igt and the required exhaust heat conversion torque TQwup, the solid line is shown by A, and for comparison, the behavior when the catalyst warm-up control is not performed is shown by the double line C. The behavior when the control device for the internal combustion engine according to No. 1 is not applied is shown by the alternate long and short dash line B.

The rotation speed Ne rises sharply with the start of the engine, greatly exceeds the target rotation speed Net, reaches a peak, and then starts to decrease. After that, the rotation speed feedback control during idle operation is started at the timing of time t1, and in order to converge the rotation speed Ne to the target rotation speed Net, the rotation speed feedback amount (I term) TQfbi and the rotation speed feedback amount (P). Item) TQfbp is increased or decreased and corrected.
FIG. 4 shows an example in which the friction loss torque is large and each rotation speed feedback amount is corrected to the increase side, and the rotation speed feedback amount (I term) TQfbi is reflected on the side where the target throttle opening Tht opens. The rotation speed feedback amount (P term) TQfbp is reflected on the side where the target ignition timing Igt advances.

At the timing of time t2 when the rotation speed Ne converges to within a predetermined value with respect to the target rotation speed Net, the rotation speed feedback amount (I term) TQfbi is maintained and the rotation speed feedback amount (P term) TQfbp is corrected. It has been reset to the state of none. When it is determined that the rotation speed feedback amount (I term) TQfbi is a deviation of the loss torque peculiar to the engine after the engine is completely warmed up, the value of the rotation speed feedback amount (I term) TQfbi is learned as loss torque. Since it is reflected in the value, the rotation speed Ne converges to the target rotation speed Net at an early stage when the cold machine is started after the learning, and the timing at time t2 is also accelerated.

The catalyst warm-up control is started after it is determined that the rotation speed Ne converges to the target rotation speed Net at the timing of time t2 and there is little concern about engine stall or abnormal rotation speed. As the catalyst warm-up control, the required exhaust heat conversion torque TQup is gradually increased up to a preset required exhaust heat conversion torque reference value TQwupb based on information such as filling efficiency (not shown). The target throttle opening Tht is controlled to the open side and the target ignition timing Igt is controlled to the retard side in conjunction with the required exhaust heat conversion torque TQwup.

Subsequently, at the timing of time t2', the increase correction for the required exhaust heat conversion torque reference value TQupb is completed. At this point, in this example in which the friction loss torque is large, the target ignition timing Igt is on the advance side of the catalyst warm-up target ignition timing Igtwup as compared with the case where the required exhaust heat conversion torque reference value TQwupb is set in advance. Therefore, sufficient early catalyst activation cannot be realized. Therefore, the required exhaust heat conversion torque correction value TQwupc is gradually increased from the timing of time t2'. This increase is increased until the target ignition timing Igt is retarded to the catalyst warm-up target ignition timing Igtwup, the target ignition timing Igt is retarded to the catalyst warm-up target ignition timing Igtwup, and the operating condition is stable for a predetermined time or longer. If it is determined that the value is satisfied, the required exhaust heat conversion torque correction value TQwupc is retained and stored. As a result, the target ignition timing Igt is retarded to the catalyst warm-up target ignition timing Igtwup on the solid line A when the present embodiment is applied, as opposed to the one-dot dashed line B when the present embodiment is not applied. On the other hand, the target throttle opening Tht is controlled to the opening side.

Then, the accelerator is depressed at the timing of time t3 to start traveling. At this time, the required exhaust heat conversion torque correction value TQwupc is continuously maintained with respect to the required exhaust heat conversion torque reference value TQwupb that changes depending on the operating state, and the required exhaust heat conversion torque TQwup is calculated. As a result, the required shaft torque required from the accelerator opening and the like can be realized by increasing the intake air flow rate while realizing the ignition retard angle for catalyst activation updated at idle even during running. ..

Then, the brake is depressed at the timing of time t4, and braking is started toward the stop. At this time, the catalyst warm-up control is temporarily interrupted even if the catalyst has not reached the light-off temperature, the required exhaust heat conversion torque TQwup is invalidated, the target throttle opening Tht is controlled to the closed side, and the target ignition timing is performed. The Igt is controlled to the advance side until it coincides with the double line C on which the catalyst warm-up control is not performed. As a result, the braking ability by the brake can be exhibited by securing the negative pressure in the intake manifold. However, in this example, the ignition retard control or the fuel cut control for deceleration is not shown.

As described above, in the control device of the internal combustion engine that controls the increase of the intake amount and the retard angle control of the ignition timing as the catalyst warm-up control regardless of whether the vehicle is idle or running, even for a vehicle having a large loss torque due to vehicle variation. It is possible to realize early activation of the catalyst while ensuring stall resistance or drivability.

Here, the ignition control required shaft torque calculating means 201, the ignition control required combustion torque calculating means 202, the target ignition timing calculating means 203, the intake control required shaft torque calculating means 204, and the intake control required combustion are described with reference to FIG. Torque calculation means 205, target throttle opening calculation means 206, required exhaust heat conversion torque reference value calculation means 301, catalyst warm-up target ignition timing calculation means 302, required exhaust heat conversion torque correction value calculation means 303. The required exhaust heat conversion torque calculation means 304 is a calculation means included in the control device of the internal combustion engine. The control device 501 of the internal combustion engine includes a processor 502 and a storage device 503, as shown in FIG. 5 as an example of hardware. Although the storage device 503 is not shown, it includes a volatile storage device such as a random access memory and a non-volatile auxiliary storage device such as a flash memory. Further, an auxiliary storage device of a hard disk may be provided instead of the flash memory. The processor 502 executes the program input from the storage device 503. In this case, the program is input from the auxiliary storage device to the processor 502 via the volatile storage device. Further, the processor 502 may output data such as a calculation result to the volatile storage device of the storage device 503, or may store the data in the auxiliary storage device via the volatile storage device.

It should be noted that the embodiment is merely an example, and the present application is not limited to such a specific embodiment, and various other embodiments are possible within the scope of the gist of the present application. In the above embodiment, the required exhaust heat conversion torque reference value is given on the map, but the required exhaust heat amount itself is given in the process of calculating the target filling efficiency from the required torque without converting the required exhaust heat amount into torque. It may be controlled or converted to torque using the target retardation timing from the catalyst warm-up target ignition timing or the preset base ignition timing during normal operation, and a coefficient that correlates with the current or predicted thermal efficiency. You may. Further, the reference map of the required exhaust heat conversion torque reference value may be switched according to the accelerator information or the number of revolutions so as to distinguish between the idle operation and the off-idle operation. When switching according to the number of revolutions, a reference value may be given on the map of the number of revolutions and the filling efficiency, and a coefficient based on the cooling water temperature may be multiplied. Further, the determination of idle driving and off-idle operation based on the accelerator opening and the determination of braking based on the brake information determine whether or not driving or braking is required when the accelerator pedal or the brake pedal is not operated as in an auto cruise device. As the information to be determined, the required torque information from the auto cruise device may be substituted.

As mentioned above, although exemplary embodiments are described in the present application, the various features, embodiments, and functions described in the embodiments are not limited to the application of a particular embodiment. , Alone, or in various combinations, are applicable to embodiments.
Therefore, innumerable variations not illustrated are envisioned within the scope of the techniques disclosed in the present application. For example, it is assumed that at least one component is modified, added or omitted.

1 Engine, 2 Electronically controlled throttle valve, 3 Throttle opening sensor, 4 Airflow sensor, 5 Surge tank, 6 Intake pressure sensor, 7 Injector, 8 Ignition coil, 9 Spark plug, 10 Crank angle sensor, 11 Air fuel ratio sensor, 12 Catalyst, 201 Ignition control required shaft torque calculation means, 202 Ignition control required combustion torque calculation means, 203 Target ignition timing calculation means, 204 Intake control required shaft torque calculation means, 205 Intake control required combustion torque calculation means, 206 Target throttle opening calculation means, 301 Required exhaust heat conversion torque reference value calculation means, 302 Catalyst warm-up target ignition timing calculation means, 303 Required exhaust heat conversion torque correction value calculation means, 304 Required exhaust heat conversion torque calculation means, 501 Internal combustion engine controller, 502 processor, 503 storage device.

Claims (5)

Required shaft torque for intake control obtained from accelerator opening, preset loss torque, rotation speed feedback amount during idle operation, and required exhaust heat conversion torque obtained by converting the required exhaust heat amount for early activation of the catalyst into torque The target throttle opening calculation means for calculating the target throttle opening based on the required combustion torque for intake control obtained from
The required retard angle from the MBT ignition timing in order to realize the required shaft torque for ignition control obtained from the accelerator opening, the loss torque, and the required combustion torque for ignition control obtained from the rotation speed feedback amount during idle operation. A target ignition timing calculation means that calculates the target ignition timing by calculating the amount,
If the target ignition timing is on the advance side of the catalyst warm-up target ignition timing that activates the catalyst early during the idle operation, the required exhaust heat conversion torque correction value is gradually increased to convert the required exhaust heat amount. The required exhaust heat conversion torque calculation means for increasing and correcting the torque,
With
When the target throttle opening degree is controlled to the open side and the idle operation is switched to the off-idle operation, the required exhaust heat conversion torque correction value is stored, and the requested exhaust heat conversion torque correction value is used. An internal combustion engine control device characterized by calculating the exhaust heat conversion torque. The required exhaust heat conversion torque correction value is held as a value when the correction is completed when the target ignition timing is retarded to the catalyst warm-up target ignition timing by the catalyst warm-up control during the idle operation. The control device for an internal combustion engine according to claim 1. The control device for an internal combustion engine according to claim 1 or 2, wherein the required exhaust heat conversion torque is invalidated when there is a request for securing a negative pressure during traveling. The required exhaust heat conversion torque is gradually increased and corrected by using the required exhaust heat conversion torque correction value stored at the time of switching from the idle operation to the off-idle operation when the catalyst warm-up control during running is restarted. The control device for an internal combustion engine according to any one of claims 1 to 3, wherein the internal combustion engine is controlled. The request amount of exhaust heat conversion torque regardless during idling and off idle operation, according to claim 1 in which the catalyst is characterized in that it is gradually decreasing correction to become disabled state after reaching the light-off temperature 4. The control device for an internal combustion engine according to any one of 4.

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