JP2015001179A - Control device for internal combustion engine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a control device for an internal combustion engine, capable of controlling an ignition timing to make actual torque of the internal combustion engine follow target torque even when auxiliary equipment is driven during executing catalyst warming-up retard control.SOLUTION: The control device for the internal combustion engine which can execute catalyst warming-up retard control includes an EG-ECU for calculating load torque required for driving an air conditioning unit in response to a request to drive an air conditioning unit to be driven utilizing an engine output and increasing a target intake air amount in intake air amount increase control depending on the load torque. The EG-ECU applies reduction correction of an increase correction amount for the target intake air amount in the intake air amount increase control depending on the retard amount (the basic retard amount) of an ignition timing during executing the catalyst warming-up retard control, and advances the ignition timing to compensate for a reduction of the load torque due to the reduction correction of the increase correction amount for the target intake air amount.

Description

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

  In general, when an auxiliary machine such as an air conditioner compressor, which becomes an engine load, is started in an idle operation state of the engine, the engine load changes suddenly and the engine speed temporarily decreases.

  Conventionally, as a control device for an internal combustion engine that suppresses a decrease in the engine speed during idling, the engine at idling is performed by increasing the intake air amount or advance the ignition timing according to the operating state of the air conditioner compressor. Has been known (for example, see Patent Document 1).

Japanese Patent Laid-Open No. 62-41951

  However, in a conventional control device for an internal combustion engine, an auxiliary device such as a compressor for an air conditioner is started in a state in which so-called catalyst warm-up retarding control is performed in which ignition timing is retarded during catalyst warm-up. If the intake air amount is increased, the actual torque that is excessive with respect to the target torque may not be reduced to the target torque.

  Specifically, when a drive request for an auxiliary machine is made during execution of the catalyst warm-up delay angle control, the intake air amount is increased in order to increase the target torque of the engine. At this time, the intake air amount becomes excessive, and the actual torque of the engine may exceed the target torque.

  In such a case, since it is necessary to reduce the actual torque, the ignition timing is controlled to the retard side by the ignition timing control that is more responsive than the feedback control of the intake air amount, and the excessive torque is reduced. Is desirable.

  However, the ignition timing has already been retarded by the catalyst warm-up retard control. For this reason, in the conventional control device for an internal combustion engine, even if it is attempted to control the ignition timing that has already been retarded further to the retard side, in consideration of the misfire limit, it may not be possible to retard further. In such a case, the actual torque of the engine cannot be reduced to the target torque.

  As described above, in the conventional control device for an internal combustion engine, when the auxiliary machine is driven during the catalyst warm-up delay angle control, the actual engine torque is made to follow the target torque by controlling the ignition timing. There was a risk of not being able to.

  The present invention has been made in view of the circumstances as described above. Even when the auxiliary machine is driven during the catalyst warm-up delay angle control, the actual torque of the internal combustion engine is controlled by controlling the ignition timing. An object of the present invention is to provide a control device for an internal combustion engine that can follow the torque.

  In order to achieve the above object, the control device for an internal combustion engine according to the present invention is (1) a control device for an internal combustion engine capable of performing catalyst warm-up retarding control for retarding ignition timing during catalyst warm-up, The load torque required to drive the auxiliary machine is calculated according to the drive request of the auxiliary machine driven using the output of the internal combustion engine, and the target intake air amount of the internal combustion engine is increased according to the load torque And a control means for correcting the decrease in the increased target intake air amount in accordance with the retard amount of the ignition timing during execution of the catalyst warm-up delay angle control, and the increased target It has a configuration that compensates for a decrease in load torque due to a reduction in intake air amount by advancing the ignition timing.

  With this configuration, the control apparatus for an internal combustion engine according to the present invention corrects the target intake air amount increased according to the retard amount of the ignition timing during execution of the catalyst warm-up retard angle control, so that the actual intake air amount is corrected. It is possible to suppress the actual intake air amount that is the air amount from exceeding the target intake air amount. Therefore, it is possible to prevent the actual torque, which is the actual torque of the internal combustion engine when driving the auxiliary equipment during catalyst warm-up, from becoming excessive with respect to the target torque. Therefore, as in the past, in order to make the actual torque of the internal combustion engine excessive with respect to the target torque follow the target torque, the ignition timing delayed by the catalyst warm-up delay control is further controlled to the retard side. There is no need to do it.

  Further, the control means compensates for the decrease in the load torque due to the decrease correction of the increased target intake air amount by advancing the ignition timing, so that the actual performance of the internal combustion engine with respect to the target torque at the time of driving the auxiliary machine during catalyst warm-up is increased. The shortage of torque can be compensated.

  Therefore, the control device for an internal combustion engine according to the present invention causes the actual torque of the internal combustion engine to follow the target torque by controlling the ignition timing even when the auxiliary device is driven during the catalyst warm-up delay angle control. be able to.

  The control apparatus for an internal combustion engine according to the present invention is the control apparatus for an internal combustion engine according to (1), wherein (2) the control means delays the ignition timing during execution of the catalyst warm-up delay angle control. As the angular amount is larger, the amount of reduction by the reduction correction of the increased target intake air amount is increased.

  With this configuration, the control device for an internal combustion engine according to the present invention increases the amount of reduction due to the reduction correction of the target intake air amount that has been increased as the amount of retardation of the ignition timing during execution of the catalyst warm-up delay angle control is larger. Therefore, the target intake air amount can be corrected to decrease so that the actual torque of the internal combustion engine does not exceed the target torque when the ignition timing is approaching the misfire limit due to a large retard amount of the ignition timing.

  According to the present invention, control of an internal combustion engine that can cause the actual torque of the internal combustion engine to follow the target torque by controlling the ignition timing even when the accessory is driven during the execution of the catalyst warm-up delay angle control. An apparatus can be provided.

1 is a schematic configuration diagram of a vehicle to which a control device for an internal combustion engine according to an embodiment of the present invention is applied. 1 is a schematic configuration diagram of an engine according to an embodiment of the present invention. It is a figure which shows the relationship between an auxiliary machine load and the increase correction amount. It is a figure which shows the relationship between an engine ignition timing and an engine torque. It is a figure which shows an example of the intake air amount reduction correction map which concerns on embodiment of this invention. It is a flowchart which shows the intake air amount reduction | decrease correction process in embodiment of this invention.

  Embodiments of the present invention will be described below with reference to the drawings.

  In the following description, an example in which the control device for an internal combustion engine according to the present invention is applied to an FR (Front engine Rear drive) vehicle equipped with a transmission will be described.

  As shown in FIG. 1, a vehicle 1 according to the present embodiment includes an engine 2 constituting an internal combustion engine, a torque converter 3 that amplifies output torque output from the engine 2, and a rotational speed of an output shaft of the torque converter 3. The transmission mechanism 5 that rotates the output shaft 4 at the rotational speed obtained by shifting the transmission shaft 4, the differential gear 7 that transmits the rotational force of the output shaft 4 of the transmission mechanism 5 to the drive shafts 6 L and 6 R, and the drive shafts 6 L and 6 R are rotated. The driving wheels 8L and 8R that are driven by this are provided.

  Here, the torque converter 3 and the transmission mechanism 5 constitute a transmission 9. As the transmission 9, it is possible to use a multi-stage automatic transmission having a plurality of shift speeds different from each other and connected to the engine 2 or a continuously variable transmission capable of continuously changing the speed ratio. As the transmission 9, a manual transmission that can switch a plurality of shift stages in accordance with a driver's shift operation may be employed. In this case, the torque converter 3 is not provided.

  Further, the vehicle 1 electrically connects an engine electronic control unit (hereinafter referred to as “EG-ECU”) 10 that controls the engine 2, a hydraulic control circuit 11 that controls the transmission 9 by hydraulic pressure, and a hydraulic control circuit 11. Electronic control unit for transmission (hereinafter referred to as “TM-ECU”) 12, air conditioning unit 13, and electronic control unit for air conditioner that controls air conditioning unit 13 (hereinafter referred to as “A / C-ECU”) 14. The EG-ECU 10 in the present embodiment constitutes a control means according to the present invention.

  As shown in FIG. 2, the engine 2 includes a cylinder block 20, a cylinder head 21 fixed to the upper part of the cylinder block 20, and an oil pan 22 that stores oil, and the cylinder block 20, the cylinder head 21, Thus, a plurality of cylinders 23 are formed.

  In the present embodiment, the engine 2 is assumed to be an in-line 4-cylinder engine. However, in the present invention, the in-line 6-cylinder engine, the V-type 6-cylinder engine, the V-type 12-cylinder engine, or the horizontal You may be comprised by various types of engines, such as an opposed 6 cylinder engine. Note that the engine 2 shown in FIG. 2 shows one cylinder 23 among four cylinders arranged in series.

  A piston 24 is accommodated in the cylinder 23 so as to be able to reciprocate. A combustion chamber 25 of each cylinder 23 is formed by the cylinder block 20, the cylinder head 21, and the piston 24. In the present embodiment, the engine 2 is described as being constituted by a four-cycle engine that performs a series of four strokes including an intake stroke, a compression stroke, a combustion stroke, and an exhaust stroke while the piston 24 reciprocates twice. To do.

  Pistons 24 housed in the cylinders 23 are connected to a crankshaft 27 via connecting rods 26. The connecting rod 26 converts the reciprocating motion of the piston 24 into the rotational motion of the crankshaft 27.

  Therefore, the engine 2 reciprocates the piston 24 by burning the fuel / air mixture in the combustion chamber 25 and rotates the crankshaft 27 via the connecting rod 26, thereby supplying power to the torque converter 3. To communicate.

  In addition, although the fuel used for the engine 2 is gasoline, it may replace with gasoline and may be alcohol fuel which mixed alcohol and gasoline, such as hydrocarbon fuels, such as light oil, and ethanol.

  The engine 2 is provided with an intake pipe 30 for introducing air into the combustion chamber 25. The intake pipe 30 includes an air cleaner 31 that cleans air flowing from outside the vehicle, an air flow sensor 32 that detects a flow rate of air introduced into the combustion chamber 25, that is, an intake air amount, and a throttle valve that adjusts the intake air amount. 33 is provided.

  The air cleaner 31 is configured to remove foreign substances in the intake air by using, for example, a paper or synthetic fiber nonwoven fabric filter accommodated therein. The air flow sensor 32 is provided on the upstream side of the throttle valve 33 and outputs a detection signal indicating the intake air amount to the EG-ECU 10.

  The opening of the throttle valve 33 is adjusted by the throttle valve actuator 34 so that the intake air amount can be adjusted. The throttle valve actuator 34 is connected to the EG-ECU 10.

  Further, the engine 2 is provided with an exhaust pipe 35 for discharging the exhaust gas in the combustion chamber 25 to the outside of the vehicle. The exhaust pipe 35 is provided with a catalyst 36 for oxidation-reduction purification of harmful substances in the exhaust gas.

  The cylinder block 20 is formed with a water jacket 37 through which cooling water circulates, and a water temperature sensor 38 that detects the temperature of the cooling water circulated through the water jacket 37. The cylinder head 21 is formed with an intake port 40 for communicating the intake pipe 30 and the combustion chamber 25 and an exhaust port 41 for communicating the combustion chamber 25 and the exhaust pipe 35.

  Further, the cylinder head 21 has an intake valve 42 for controlling the introduction of combustion air from the intake pipe 30 to the combustion chamber 25 and an exhaust valve for controlling the discharge of exhaust gas from the combustion chamber 25 to the exhaust pipe 35. An exhaust valve 43, an injector 44 for injecting fuel into the combustion chamber 25, and a spark plug 45 for igniting the air-fuel mixture in the combustion chamber 25 are provided.

  The injector 44 and the spark plug 45 are connected to the EG-ECU 10, and the EG-ECU 10 controls the propriety and timing of fuel injection, the ignition timing, and the like.

  The crankshaft 27 is provided with a crank rotor (not shown) that rotates together with the crankshaft 27. The engine 2 includes a crank angle sensor 61 for detecting the rotation angle of the crank rotor.

  The crank angle sensor 61 is connected to the EG-ECU 10 and outputs a crank angle signal corresponding to the detection result to the EG-ECU 10.

  The hydraulic control circuit 11 is provided with various solenoids, and controls speed change, line pressure, and lock-up state via these solenoids.

  In FIG. 1, an EG-ECU 10 is a microprocessor that includes a CPU (Central Processing Unit), a ROM (Read Only Memory), a RAM (Random Access Memory), a flash memory, and an input / output port (not shown). It is configured.

  A program for causing the microprocessor to function as the EG-ECU 10 is stored in the ROM of the EG-ECU 10. That is, the CPU of the EG-ECU 10 functions as the EG-ECU 10 by executing a program stored in the ROM using the RAM as a work area.

  In the present embodiment, on the input side of the EG-ECU 10, in addition to the crank angle sensor 61, the airflow sensor 32, and the water temperature sensor 38, an accelerator opening sensor 91 that detects an accelerator opening representing the opening of the accelerator pedal 90 is provided. Are connected to a vehicle speed sensor 92 for detecting the vehicle speed.

  The accelerator opening sensor 91 outputs a signal representing the accelerator opening indicating the opening of the accelerator pedal 90 to the EG-ECU 10 when the accelerator pedal 90 is operated by the driver.

  The vehicle speed sensor 92 detects the rotation angles of the drive shafts 6L and 6R, and outputs a signal representing the vehicle speed obtained by averaging the detected rotation angles of the drive shafts 6L and 6R to the EG-ECU 10.

  The EG-ECU 10 communicates with other ECUs such as the TM-ECU 12 and the A / C-ECU 14 via the high-speed CAN, and performs various controls with other ECUs such as the TM-ECU 12 and the A / C-ECU 14. Signals and data are exchanged.

  For example, the EG-ECU 10 controls the fuel injection control for the injector 44, the ignition control for the spark plug 45, and the intake air amount for the throttle valve actuator 34 based on detection signals input from various sensors that detect the operating state of the engine 2. While performing operation control of the engine 2 such as adjustment control, data related to the operation state of the engine 2 is output to the TM-ECU 12 as necessary.

  Further, the EG-ECU 10 controls ISC control, catalyst warm-up delay control for retarding the ignition timing during catalyst warm-up, and auxiliary equipment such as an air conditioning unit 13 to be described later as part of operation control of the engine 2. The intake air amount increase control for increasing the intake air amount of the engine 2 as it is driven is executed.

  The ISC control is a control that is executed to maintain the idle speed of the engine 2 at the target idle speed when the engine 2 is idling. Specifically, the EG-ECU 10 sets the target idle speed in advance as a low speed at which the engine 2 can be idle without causing a stall, and maintains the idle speed at the target idle speed. The intake air amount at the time is feedback controlled.

  The catalyst warm-up delay angle control is a control for retarding the ignition timing in order to activate the catalyst 36 at the time of cold start of the engine 2 to increase the exhaust purification efficiency, and this catalyst warm-up delay angle control is executed. As a result, the warm-up of the catalyst 36 is promoted. Further, the EG-ECU 10 is configured to simultaneously execute control for increasing the intake air amount in accordance with the retard amount in order to maintain the idle speed.

  The intake air amount increase control is a control for maintaining the idle speed of the engine 2 in a stable state when a load (auxiliary load) due to driving of auxiliary equipment such as the air conditioning unit 13 increases.

  The EG-ECU 10 sets the target rotational speed of the engine 2 based on the cooling water temperature or the like when the engine 2 is idling, and feedback-controls the intake air amount in accordance with the deviation between the target rotational speed and the actual rotational speed. It is like that. In the idling operation state where the intake air amount feedback control is performed, for example, when the air conditioning unit 13 is driven, a drop in the engine speed occurs due to the auxiliary load accompanying the driving of the air conditioning unit 13.

  Therefore, in order to prevent such a decrease in engine speed during idle operation, the EG-ECU 10 increases the intake air amount and increases the engine output when auxiliary equipment such as the air conditioning unit 13 is driven in the idle operation state. Is to increase.

  Specifically, the EG-ECU 10 calculates a load torque necessary for driving the auxiliary machinery according to the driving request of the auxiliary machinery such as the air conditioning unit 13, and feedbacks the intake air amount according to the calculated load torque. The target intake air amount in the control is corrected to increase, that is, the target intake air amount is increased. Then, the EG-ECU 10 increases the opening of the throttle valve 33 via the throttle valve actuator 34 so that the actual intake air amount (hereinafter referred to as the actual intake air amount) becomes the target intake air amount that has been corrected to increase. It is like that.

  Here, the above-described accessories are devices that are driven using the output of the engine 2, and examples include an alternator and a power steering device in addition to the air conditioning unit 13. In the present embodiment, an air conditioning unit 13 will be described as an example of the auxiliary machines.

  The TM-ECU 12 is configured by a microprocessor that includes a CPU, a ROM, a RAM, a flash memory, and an input / output port (not shown). A program for causing the microprocessor to function as the TM-ECU 12 is stored in the ROM of the TM-ECU 12.

  That is, the CPU of the TM-ECU 12 functions as the TM-ECU 12 by executing a program stored in the ROM using the RAM as a work area.

  In the present embodiment, a shift position sensor 94 that detects the shift position selected by the shift lever 93 is connected to the input side of the TM-ECU 12.

  The TM-ECU 12 communicates with other ECUs such as the EG-ECU 10 and the A / C-ECU 14 via the high-speed CAN, and performs various controls with other ECUs such as the EG-ECU 10 and the A / C-ECU 14. Signals and data are exchanged.

  For example, the TM-ECU 12 controls the hydraulic control circuit 11 based on the shift position detected by the shift position sensor 94 and the operating state of the engine 2 output from the EG-ECU 10, so Are formed, and information representing the speed stage formed in the speed change mechanism 5 is output to the EG-ECU 10.

  The air conditioning unit 13 is housed in the engine room of the vehicle 1, and includes a compressor 101 as a compressor, a condenser 102 as a condenser, an expansion valve 103 as a decompression unit, and an evaporator 104 as a heat exchanger. It has.

  The compressor 101, the condenser 102, the expansion valve 103, and the evaporator 104 are communicated with each other through the refrigerant circulation path 100, and the refrigeration cycle is executed by circulating the refrigerant through the refrigerant circulation path 100. As the refrigerant, for example, an antifreeze liquid used as engine cooling water is used. Note that a gas such as carbon dioxide may be used as the refrigerant instead of the antifreeze liquid. The air conditioning unit 13 according to the present embodiment constitutes an auxiliary machine according to the present invention.

  The compressor 101 compresses the refrigerant in the low pressure gas phase state and discharges it in the high temperature and high pressure superheated gas phase state. The compressor 101 is connected to the crankshaft 27 of the engine 2 via a drive belt 105 and a pulley 106. Therefore, when the crankshaft 27 rotates, the compressor 101 is driven by the driving force output from the engine 2. Therefore, when the air conditioning unit 13 is in an operating state, that is, when the compressor 101 is being driven, the driving torque of the compressor 101 at this time is the engine 2 as an external load (auxiliary load), that is, a load of the air conditioning unit 13. Act on.

  The compressor 101 is a variable displacement compressor. The variable capacity compressor 101 adjusts the refrigerant suction pressure by changing the stroke of the piston by changing the current value of the energization current to the solenoid by the A / C-ECU 14 (to be described later) or changing the duty ratio. ing.

  The condenser 102 is connected to the downstream side of the compressor 101 in the refrigerant circuit 100, and is disposed, for example, on the front surface of the radiator. The condenser 102 is configured to cool the superheated gas phase refrigerant discharged from the compressor 101 to the condensation point by a vehicle wind during driving or a wind of a cooling electric fan (not shown) to a liquid phase state.

  The expansion valve 103 is disposed downstream of the capacitor 102, and depressurizes the liquid-phase refrigerant that has flowed out of the capacitor 102 to a low-pressure liquid-phase state.

  The evaporator 104 evaporates the low-pressure liquid phase refrigerant that has flowed out of the expansion valve 103 into a low-pressure gas-phase state, and constitutes an evaporator. The evaporator 104 is disposed in an air conditioning duct (not shown) that communicates between the interior and exterior of the vehicle. The evaporator 104 cools the air-conditioning air by exchanging heat between the refrigerant circulating in the refrigerant circuit 100 and the air-conditioning air sucked into the air-conditioning duct and passing through the evaporator 104. .

  The A / C-ECU 14 is configured by a microprocessor having a CPU (Central Processing Unit), a ROM (Read Only Memory), a RAM (Random Access Memory), a flash memory, and an input / output port (not shown). ing.

  A program for causing the microprocessor to function as the A / C-ECU 14 is stored in the ROM of the A / C-ECU 14. That is, when the CPU of the A / C-ECU 14 executes a program stored in the ROM using the RAM as a work area, the microprocessor functions as the A / C-ECU 14.

  The A / C-ECU 14 communicates with other ECUs such as the EG-ECU 10 and the TM-ECU 12 via the high-speed CAN, and various control signals and other ECUs such as the EG-ECU 10 and the TM-ECU 12 It is designed to exchange data.

  The A / C-ECU 14 is supplied with switch signals from switches on a control panel provided on the front surface of the vehicle interior. Here, each switch on the control panel includes an air conditioner (A / C) switch for instructing to drive and stop the compressor 101, a temperature setting switch for setting the temperature in the passenger compartment to a desired temperature, Examples include an air volume switching switch for switching the air volume, an air outlet switching switch for switching the air outlet mode, and the like.

  The A / C-ECU 14 controls the rotational speed of a blower fan (not shown), for example, by driving a blower motor in accordance with signals input from the above-described various sensors, switches, and the like. Controls the airflow (blower airflow) of the conditioned air blown out.

  By the way, in the vehicle 1 configured as described above, for example, when the air conditioning unit 13 is driven as an auxiliary machine of the engine 2 during execution of the catalyst warm-up delay angle control, the following problems may occur.

  That is, when the air conditioning unit 13 is driven, the target intake air amount is increased and corrected by the intake air amount increase control.

  Normally, in this increase correction of the target intake air amount, as shown in FIG. 3, the increase correction amount is increased from substantially the center or the center of the variation width in consideration of the variation in the auxiliary equipment load of the air conditioning unit 13. Set to the side. The actual intake air amount is increased by the increase correction of the target intake air amount. The normal time is a state in which the air conditioning unit 13 is not driven, for example.

  Here, when the auxiliary load of the air conditioning unit 13 varies to a smaller side during the catalyst warm-up delay angle control, the actual torque of the engine 2 (hereinafter referred to as the intake air amount increased by the increase correction). May be excessive with respect to the target torque. In this case, the engine speed of the engine 2 is increased.

  At this time, even if the actual torque of the engine 2 is to be reduced, during the execution of the catalyst warm-up delay angle control, as shown in FIG. 4, the ignition timing has already been retarded and therefore the misfire limit is approached. In some cases, the ignition timing cannot be retarded.

  In such a case, the torque of the engine 2 cannot be reduced by the ignition timing control. Therefore, the torque of the engine 2 needs to be reduced by feedback control of the intake air amount that is less responsive than the ignition timing control. This is not preferable because the engine speed increases for a predetermined period.

  Therefore, in the present embodiment, in order to eliminate the above-described problems, when the auxiliary equipment such as the air conditioning unit 13 is driven during the catalyst warm-up delay angle control, the intake air amount increase control is performed. Thus, the amount of increase in the target intake air amount that is corrected for increase, that is, the intake air amount decrease correction process for decreasing the increase correction amount is executed. This intake air amount decrease correction process is executed by the EG-ECU 10.

  Specifically, the EG-ECU 10 corrects the increase correction amount of the target intake air amount in the intake air amount increase control in accordance with the retard amount of the ignition timing during execution of the catalyst warm-up delay angle control. ing. In other words, the EG-ECU 10 corrects a decrease in the target intake air amount increased by the intake air amount increase control according to the retard amount of the ignition timing during execution of the catalyst warm-up delay angle control. Yes. Further, at this time, the EG-ECU 10 compensates for a decrease in the above-described load torque (load torque necessary for driving the auxiliary machinery) due to a decrease correction of the increased target intake air amount by advancing the ignition timing. It is like that.

  Further, the EG-ECU 10 determines a decrease amount of the increase correction amount of the target intake air amount to be corrected in the intake air amount decrease correction process with reference to a map shown in FIG. The map shown in FIG. 4 is obtained by experimentally determining in advance the relationship between the retard amount of the ignition timing during the catalyst warm-up retard control and the decrease amount of the increase correction amount of the target intake air amount. Is stored in the ROM.

  Here, the map shown in FIG. 4 has a characteristic that the amount of decrease in the increase correction amount increases as the retard amount of the ignition timing increases. Therefore, the EG-ECU 10 performs the reduction amount related to the decrease correction of the increase correction amount of the target intake air amount, that is, the intake air amount increase control as the ignition timing delay amount during execution of the catalyst warm-up delay angle control is larger. The amount of decrease due to the decrease correction of the increased target intake air amount is increased.

  Next, the intake air amount reduction correction process will be described with reference to FIG.

  The intake air amount decrease correction process shown in FIG. 6 is repeatedly executed by the EG-ECU 10 at predetermined time intervals.

As shown in FIG. 6, the EG-ECU 10 determines whether or not a predetermined predetermined weight reduction condition is satisfied (step S1). Specifically, the EG-ECU 10 determines whether all the following conditions (1) to (5) are satisfied.
(1) The catalyst warm-up delay angle control is being executed (2) Preparation for feedback control related to ISC control is completed (3) The coolant temperature is equal to or higher than a predetermined temperature (4) The air conditioning unit 13 (5) The current engine speed (idle speed) is not significantly different from the target engine speed (target idling speed).

  Here, whether or not the catalyst warm-up delay angle control is being executed is, for example, whether or not the catalyst warm-up delay angle control is retarded with respect to the ignition timing (see FIG. 4) in a normal idling operation state that does not require catalyst warm-up. That is, it can be determined by whether or not there is a basic retardation amount. Note that the basic retard amount in the catalyst warm-up retard control is calculated based on, for example, a map (not shown) showing the relationship between the coolant temperature and the engine load factor.

  In addition, the fact that the preparation for feedback control related to ISC control is completed means that, for example, the transient due to ON / OFF of the compressor 101 is not performed even when feedback control is not actually performed, except when the intake air amount is actually feedback controlled. It is a concept including a preparation stage of feedback control in the period.

  Further, that the cooling water temperature is equal to or higher than the predetermined temperature includes that the water temperature sensor 38 has not failed.

  Further, whether or not the compressor 101 is in transition can be determined based on whether or not the compressor 101 is driven and less than a predetermined time from the start of driving of the compressor 101. For example, when the compressor 101 is driven and it is less than a predetermined time from the start of driving the compressor 101, it is determined that the compressor 101 is in a transient state.

  In the present embodiment, when all the conditions (1) to (5) are satisfied, it is determined that a predetermined weight reduction condition is satisfied. In addition, when only the above (1) is satisfied, it may be determined that a predetermined weight reduction condition is satisfied.

  If the EG-ECU 10 determines that the predetermined weight reduction condition has not been established, the EG-ECU 10 ends this process.

  On the other hand, if the EG-ECU 10 determines that the predetermined reduction condition is satisfied, the EG-ECU 10 calculates a reduction amount of the target intake air amount increase correction amount (step S2). Specifically, the EG-ECU 10 refers to the map shown in FIG. 4 and calculates a reduction amount corresponding to the retard amount (basic retard amount) of the ignition timing at the catalyst warm-up retard control.

  Next, the EG-ECU 10 executes a predetermined annealing process for slowing the change in the amount of reduction calculated in step S2 (step S3). Thereafter, the EG-ECU 10 reflects the decrease amount after the annealing process in the increase correction amount of the target intake air amount (step S4), and ends this process. By reflecting the decrease amount in the increase correction amount, the increase correction amount of the target intake air amount in the intake air amount increase control is decreased. That is, the target intake air amount in the intake air amount increase control is corrected to be reduced compared to the case where the intake air amount decrease correction process shown in FIG. 6 is not executed.

  As described above, the control device for the internal combustion engine according to the present embodiment has the target intake air amount increased in accordance with the retard amount (basic retard amount) of the ignition timing during execution of the catalyst warm-up retard control. Therefore, the actual intake air amount, which is the actual intake air amount, can be prevented from exceeding the target intake air amount.

  Therefore, it is possible to prevent the actual torque, which is the actual torque of the engine 2 when driving the auxiliary equipment such as the air conditioning unit 13 during catalyst warm-up, from becoming excessive with respect to the target torque. Therefore, as in the prior art, the ignition timing retarded by the catalyst warm-up retard control is further controlled to the retard side in order to cause the actual torque of the engine 2 that is excessive relative to the target torque to follow the target torque. There is no need to do it.

  Further, since the EG-ECU 10 compensates for a decrease in the load torque due to the decrease correction of the increased target intake air amount by advancing the ignition timing, the engine 2 with respect to the target torque at the time of driving the auxiliary machine during the catalyst warm-up. The shortage of actual torque can be compensated.

  Therefore, the control apparatus for an internal combustion engine according to the present embodiment performs the actual operation of the engine 2 by controlling the ignition timing even when an auxiliary machine such as the air conditioning unit 13 is driven during the catalyst warm-up delay angle control. The torque can be made to follow the target torque.

  Further, the control device for an internal combustion engine according to the present embodiment increases the amount of reduction due to the reduction correction of the target intake air amount that is increased as the amount of retardation of the ignition timing during execution of the catalyst warm-up delay angle control is larger. Therefore, the target intake air amount can be corrected to be reduced so that the actual torque of the engine 2 does not exceed the target torque when the ignition timing is approaching the misfire limit because the ignition timing retard amount is large.

  In the present embodiment, the example in which the control device for an internal combustion engine according to the present invention is applied to an FR vehicle has been described. However, the control device for an internal combustion engine according to the present invention is applied to an FF (Front engine Front drive) vehicle. Alternatively, it may be applied to a four-wheel drive vehicle.

  In this embodiment, an example in which ISC control is executed by adjusting the opening degree of the throttle valve 33 has been described. However, an idle speed control valve is separately provided, and ISC control is executed by adjusting the opening degree of the idle control valve. May be.

  As described above, the control apparatus for an internal combustion engine according to the present invention targets the actual torque of the internal combustion engine by controlling the ignition timing even when the auxiliary machine is driven during the catalyst warm-up delay angle control. This is useful for a control device for an internal combustion engine that can follow the torque and can execute catalyst warm-up delay angle control during catalyst warm-up.

DESCRIPTION OF SYMBOLS 1 ... Vehicle, 2 ... Engine (internal combustion engine), 10 ... EG-ECU (control means), 13 ... Air-conditioning unit (auxiliary machine), 14 ... A / C-ECU, 32 ... Air flow sensor, 33 ... Throttle valve, 34 ... Throttle valve actuator, 36 ... Catalyst, 45 ... Spark plug, 101 ... Compressor

Claims (2)

A control device for an internal combustion engine capable of executing catalyst warm-up delay angle control for retarding ignition timing during catalyst warm-up,
The load torque required to drive the auxiliary machine is calculated according to the drive request of the auxiliary machine driven using the output of the internal combustion engine, and the target intake air amount of the internal combustion engine is increased according to the load torque Control means for
The control means corrects a decrease in the increased target intake air amount in accordance with a retard amount of the ignition timing during execution of the catalyst warm-up delay angle control, and corrects a decrease in the increased target intake air amount. A control apparatus for an internal combustion engine, which compensates for a decrease in load torque due to the ignition timing by advancing the ignition timing.   The control means increases the amount of reduction by the reduction correction of the increased target intake air amount as the amount of retardation of the ignition timing during execution of the catalyst warm-up delay angle control is larger. 2. A control device for an internal combustion engine according to 1.

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