JP7067850B2 - Vehicle control device - Google Patents

Description

The present invention relates to an internal combustion engine mounted as a prime mover in a vehicle and a control device for controlling an air conditioner for air-conditioning a vehicle interior.

The air conditioner, which works to control the temperature inside the vehicle, compresses the gaseous refrigerant with a compressor that rotates by receiving engine torque transmitted from the internal combustion engine, dissipates the compressed refrigerant in the condenser, and liquefies it. It is guided to an evaporator to vaporize and exchange heat with the air in the room. A magnet clutch that connects and disconnects the internal combustion engine and the compressor for compressing the refrigerant is interposed, and the clutch is engaged when the air conditioner is operated to operate the compressor. When the air conditioner is not operating, the clutch is released to stop the operation of the compressor (see Patent Document 1 below).

When the driver requests deceleration of the vehicle without depressing the accelerator pedal while the vehicle is running, it is conceivable to recover the kinetic energy of the vehicle to improve efficiency and fuel efficiency. For example, the compressor for compressing the refrigerant is of a variable capacity type, and a cold storage agent is attached to the evaporator, the discharge capacity of the refrigerant by the compressor is intentionally increased when the vehicle is decelerated, and the generated cold heat is stored in the cold storage agent. Attempts have been made to use it for later air conditioning (see Patent Document 2 below). However, it is undeniable that the cost will increase due to the adoption of a variable displacement compressor and the addition of a cold storage agent to the evaporator.

If you try to regenerate the vehicle during deceleration only by switching the engagement and disengagement of the clutch that connects the internal combustion engine and the compressor without using a cold storage agent, if the compressor continues to operate with the clutch engaged for a long time, The temperature of the evaporator becomes extremely low, and it becomes difficult to keep the temperature of the air blown into the vehicle interior at an appropriate temperature.

Japanese Unexamined Patent Publication No. 2017-172423 Japanese Unexamined Patent Publication No. 2015-033994

An object of the present invention is to improve the control during deceleration running when the driver does not depress the accelerator pedal to improve the practical fuel consumption.

In the present invention, a fuel cut is executed in which the fuel supply to the cylinder of the internal combustion engine is temporarily interrupted on the condition that the amount of depression of the accelerator pedal by the driver is 0 or less than the threshold value close to 0 while the vehicle is running. Also, when the temperature of the evaporator of the air conditioner that air-conditions the passenger compartment or its vicinity rises above the operating condition temperature, a clutch interposed between the internal combustion engine and the compressor for compressing the refrigerant is engaged to output the internal combustion engine. When at least a part of the engine torque is supplied to the compressor to operate the compressor and the temperature of the evaporator or its vicinity drops below the cut condition temperature lower than the operating condition temperature, the clutch is disengaged and the engine torque is applied. The operation of the compressor is stopped without supplying the engine to the compressor, the fuel is cut while the vehicle is running, the vehicle speed or engine speed is higher than a predetermined value, and the operation of the compressor is stopped most recently. A vehicle control device is configured in which the difference between the operating condition temperature and the cut condition temperature when a predetermined time has elapsed has been set to be smaller than the difference when the predetermined time has not passed.

According to the present invention, it is possible to improve the control during deceleration running when the driver does not depress the accelerator pedal to improve the practical fuel consumption.

The figure which shows the outline of the internal combustion engine for a vehicle and the control device in one Embodiment of this invention. The figure which shows typically the drive system of the vehicle in the same embodiment. The figure which shows typically the structure of the air conditioner for a vehicle in the same embodiment. The flow diagram which shows the procedure example of the process which the control device of the same embodiment executes according to a program. The timing diagram explaining the content of the control performed by the control device of the same embodiment.

An embodiment of the present invention will be described with reference to the drawings. FIG. 1 shows an outline of an internal combustion engine 100 mounted on a vehicle as a prime mover. The vehicle internal combustion engine 100 is, for example, a spark-ignition type 4-stroke engine, and includes a plurality of cylinders 1 (one of which is illustrated in FIG. 1). An injector 11 for injecting fuel is provided in the vicinity of the intake port of each cylinder 1. Further, a spark plug 12 is attached to the ceiling of the combustion chamber of each cylinder 1. The spark plug 12 induces a spark discharge between the center electrode and the ground electrode in response to the application of the induced voltage generated by the ignition coil. The ignition coil is integrally built in the coil case together with the igniter having a semiconductor switching element.

The intake passage 3 for supplying intake air takes in air from the outside and guides it to the intake port of each cylinder 1. An air cleaner 31, an electronic throttle valve 32, a surge tank 33, and an intake manifold 34 are arranged on the intake passage 3 in this order from the upstream.

The exhaust passage 4 for exhausting the exhaust guides the exhaust generated as a result of burning the fuel in the cylinder 1 to the outside from the exhaust port of each cylinder 1. An exhaust manifold 42 and a three-way catalyst 41 for purifying exhaust gas are arranged on the exhaust passage 4.

The exhaust gas recirculation device 2 realizes a so-called high-pressure loop EGR in which a part of the exhaust gas flowing through the exhaust passage 4 is returned to the intake passage 3 and mixed with the intake air.

FIG. 2 shows an example of a drive system transmission provided in a vehicle. This transmission includes a torque converter 7 and automatic transmissions 8 and 9. As components of the automatic transmissions 8 and 9, for example, a forward / backward switching device 8 using a known planetary gear mechanism and a belt-type continuously variable transmission 9 which is a kind of continuously variable transmission are used. Can be adopted.

The engine torque output by the internal combustion engine 100 is input from the crankshaft, which is the output shaft of the internal combustion engine 100, to the pump impeller 71 on the input side of the torque converter 7, and is transmitted to the turbine runner 72 on the output side. The rotation of the turbine runner 72 is transmitted to the drive shaft 94 of the CVT 9 via the forward / backward switching device 8, and the driven shaft 95 is rotated through the shift in the CVT 9. The rotation of the driven shaft 95 is transmitted to the output gear 101. The output gear 101 meshes with the ring gear 102 of the differential device, and rotates the axle 103 and the drive wheels attached to the axle 103 via the differential device.

The torque converter 7 includes a lock-up mechanism. The lock-up mechanism is known in this field, and is a hydraulic fluid for driving the lock-up clutch 73 that fastens the input side and the output side of the torque converter 7 so as not to rotate relative to each other, and the lock-up clutch 73. The element is a lock-up solenoid valve (not shown) that controls pressure (hydraulic pressure). The lock-up solenoid valve is a flow rate control valve that receives a control signal t and changes its opening degree.

In a vehicle equipped with the CVT 9, when the vehicle speed is at least a certain level (for example, the vehicle speed is 10 km / h or more, or the engine speed is 1200 rpm or more), the torque converter 7 is almost always locked up. When the vehicle speed becomes lower than that (for example, 5 km / h to 8 km / h or less), the lockup of the torque converter 7 is released. At the time of lockup, the speed ratio, which is the ratio of the output side rotation speed of the torque converter 7 to the input side rotation speed, is 1. At the time of non-lockup, the speed ratio of the torque converter 7 becomes smaller or larger than 1 depending on the driving state.

FIG. 3 shows the configuration of the air conditioner 5 that air-conditions the interior of the vehicle. The air conditioner 5 includes a compressor 51 that compresses and increases the pressure of the refrigerant, a condenser 52 that dissipates and liquefies the compressed high-pressure refrigerant, and a condenser fan 53 for forcibly air-cooling the condenser 52, and does not liquefy. A receiver 54 that separates the gaseous refrigerant from the liquefied refrigerant, an expansion valve 55 that ejects the liquefied refrigerant, an evaporator 56 that receives the ejected and vaporized refrigerant and exchanges heat with the air in the room, and a heated internal combustion engine. A heater core 59 that receives 100 cooling water and exchanges heat with the air in the room, a blower fan 57 that sucks the air in the room and discharges it toward the evaporator 56 and sends the air back into the room, and an evaporator discharged from the blower fan 57. The element includes an air mix damper 50 that adjusts how much air that has passed through 56 is blown to the heater core 59. The compressor 51, the condenser 52, the receiver 54, the expansion valve 55 and the evaporator 56 are connected by a looping refrigerant flow path.

The compressor 51 is a kind of auxiliary machine attached to the internal combustion engine 100, and is rotationally driven by receiving engine torque transmitted from a crankshaft which is an output shaft of the internal combustion engine 100 to compress a refrigerant. A magnet clutch 6 capable of disconnecting and connecting the connection between the crankshaft of the internal combustion engine 100 and the compressor 51 is interposed. The rotation speed of the compressor 51 driven by the internal combustion engine 100 is proportional to the engine rotation speed.

The condenser 52 is arranged at a portion of the engine room of the vehicle where the running wind hits, and is cooled by the running wind blown into the engine room while the vehicle is running, regardless of whether the condenser fan 53 is rotated or not. Behind the condenser 52 is a radiator 7 that dissipates heat from the cooling water of the internal combustion engine 100. The radiator 7 is also cooled by the running wind.

The condenser fan 53 also serves as a radiator fan for forcibly air-cooling the radiator 7 that dissipates the cooling water of the internal combustion engine 100. The condenser fan / radiator fan 53 is located behind the radiator 7, and cools both the condenser 52 and the radiator 7 by sucking air from the front and discharging the air to the rear.

When the air discharged from the blower fan 57 passes through the evaporator 56, it obtains cold heat from the refrigerant (heat is taken away by the refrigerant) and the temperature is lowered. At the same time, the water vapor contained in the air condenses and adheres to the evaporator 56, and the humidity decreases. The evaporator 56 plays a role not only for cooling that lowers the temperature in the room in summer, but also for lowering the humidity in the room in winter to reduce fogging of the window glass of the vehicle.

The air mix damper 50 adjusts the ratio of the amount of air that has passed through the evaporator 56 to the room through the heater core 59 and the amount of air that bypasses the heater core 59 and heads into the room. With this air mix damper 50, it is possible to adjust the temperature of the wind blown into the room.

The electronic control unit (Electronic Control Unit) 0, which is a vehicle control device of the present embodiment, is a microcomputer system having a processor, a memory, an input interface, an output interface, and the like. The ECU 0 may be a plurality of ECUs or controllers connected to each other so as to be able to communicate with each other via a telecommunication line such as CAN (Control Area Network).

The input interface of ECU 0 has a vehicle speed signal a output from a vehicle speed sensor that detects the actual vehicle speed of the vehicle, a crank angle signal output from a crank angle sensor that detects the rotation angle of the crank shaft of the internal combustion engine 100 and the engine rotation speed. b, accelerator opening signal c output from a sensor that detects the amount of depression of the accelerator pedal by the driver as the accelerator opening (so to speak, the engine load factor required for the internal combustion engine 100), intake passage 3 (particularly, The intake air temperature / intake pressure signal d output from the temperature / pressure sensor that detects the intake air temperature and intake pressure in the surge tank 33), and the cooling output from the water temperature sensor that detects the cooling water temperature that suggests the temperature of the internal combustion engine 100. The water temperature signal e, the air fuel ratio signal f output from the air fuel ratio sensor that detects the air fuel ratio of the exhaust gas flowing through the exhaust passage 4, and the temperature of the evaporator 56 or its vicinity (may be downstream of the evaporator 56) are detected. Evaporator temperature signal g output from the temperature sensor, refrigerant pressure signal output from the refrigerant pressure sensor that detects the pressure of the refrigerant flowing down from the condenser 52 of the air conditioner 5 (downstream of the condenser 52 and upstream of the expansion valve 55). h etc. are input.

From the output interface of ECU 0, the ignition signal i for the igniter 13, the fuel injection signal j for the injector 11, the opening operation signal k for the throttle valve 32, and the opening operation for the EGR valve of the EGR device 2 Signal l, clutch engagement signal o for the switch on the electric circuit that energizes the magnet clutch 6, opening operation signal t for the lockup solenoid valve for switching the disconnection / disconnection of the lockup clutch 73, forward / backward switching device 8 The opening operation signal u is output to the solenoid valve for switching the disconnection / disconnection of the forward brake or the reverse clutch, and the gear ratio control signal v or the like is output to the CVT 9.

The processor of ECU 0 interprets and executes a program stored in the memory, calculates an operation parameter, and controls the operation of the internal combustion engine 100. The ECU 0 acquires various information a, b, c, d, e, f, g, h necessary for the operation control of the internal combustion engine 100 via the input interface, obtains the engine rotation speed, the intake pressure, and the like, and at the same time, obtains the engine rotation speed, the intake pressure, and the like. Required fuel injection amount, fuel injection timing (including the number of fuel injections per combustion), fuel injection pressure, ignition timing to the air-fuel mixture, corresponding to the intake amount (or fresh air amount) filled in the cylinder 1. Various operating parameters such as the required EGR rate (or EGR amount), ON / OFF of the operation of the compressor 51 of the air conditioner 5, whether to lock up the torque converter 7, and the gear ratio of the CVT 9 are determined. The ECU 0 applies various control signals i, j, k, l, o, t, u, v corresponding to the operation parameters via the output interface.

The ECU 0 executes a fuel cut that temporarily suspends the fuel supply to the cylinder 1 according to the operating condition of the vehicle. That is, the ECU 0 stops the fuel injection from the injector 11 when the predetermined fuel cut condition is satisfied. In ECU 0, at least the amount of depression of the accelerator pedal by the driver is 0 or less than the threshold value close to 0, the temperature of the internal combustion engine 100 (cooling water temperature) is higher than a predetermined value, the torque converter 7 is locked up, and the vehicle speed is high. Alternatively, it is judged that the fuel cut condition is satisfied when the engine speed is higher than the fuel cut permitted speed.

After that, when the predetermined fuel cut end condition is satisfied, the ECU 0 restarts the fuel injection from the injector 11 by returning from the fuel cut. The ECU 0 has a fuel cut end condition, such as the amount of depression of the accelerator pedal exceeds the threshold value, the lockup of the torque converter 7 is released, the vehicle speed or the engine speed has decreased to the fuel cut return speed, and the like. Is determined to have been established.

Further, the ECU 0 can execute an idle stop to stop the idle rotation of the internal combustion engine 100 when a predetermined idle stop condition is satisfied. In ECU 0, the amount of depression of the brake pedal or the master cylinder pressure is equal to or higher than the threshold value (the brake pedal is depressed), the temperature of the internal combustion engine 100 is higher than a predetermined value, and the charge amount or terminal voltage of the vehicle-mounted battery is higher than the predetermined value. High, the shift range is the driving range, the absolute value of the slope of the road surface where the vehicle is located is below the specified value, the magnitude of the negative pressure stored in the brake booster is above the threshold, and the previous idle stop ends. The idle stop condition is based on the fact that various conditions such as a history of accelerating to a certain vehicle speed (for example, 10 km / h) or more and a current vehicle speed of a certain vehicle speed (for example, 9 km / h) or less are all satisfied. Is determined to have been established.

After the idle stop condition is satisfied, when the predetermined idle stop end condition is satisfied, the internal combustion engine 100 is restarted. In ECU0, the depression amount of the brake pedal or the master cylinder pressure became 0 or less than the threshold value close to 0 (the brake pedal could not be depressed), and conversely, the depression amount of the brake pedal or the master cylinder pressure further increased (brake). The pedal is depressed more strongly), the accelerator opening is increased (accelerator pedal is depressed), the magnitude of the negative pressure stored in the brake booster drops below the threshold, and the idle stop state is set for a predetermined time (for example). It is judged that the idle stop end condition is satisfied by any of the following, such as the elapse of 3 minutes).

When starting the stopped internal combustion engine 100 (including not only the return from the idling stop but also the cold start), the ECU 0 rotates the crankshaft by an electric motor (starter or ISG (Integrated Starter Generator), not shown). Crank to make. The cranking ends when the internal combustion engine 100 goes from the first explosion to the continuous explosion and the engine speed exceeds the complete explosion determination value, assuming that the internal combustion engine 100 has completely exploded. The complete explosion determination value, which is the end condition of cranking, may fluctuate depending on the temperature of the internal combustion engine 100 and the like. Specifically, the lower the cooling water temperature of the internal combustion engine 100, the higher the setting.

In the ECU 0 of the present embodiment, the magnet clutch 6 is used in a situation where a command to operate the air conditioner 5 is given by a passenger including the driver of the vehicle and the compressor 51 should be operated to execute the compression of the refrigerant. It is fastened and the crankshaft of the internal combustion engine 100 and the compressor 51 are connected. As a result, the engine torque output by the internal combustion engine 100 is supplied to the compressor 51, the compressor 51 rotates, and the amount and pressure of the refrigerant discharged by the compressor 51 increase. The command to operate the air conditioner 5 is given, for example, by the passenger operating the air conditioner switch provided in the cockpit to ON by hand. The situation in which the compressor 51 should be operated is typically when the temperature at or near the evaporator 56 rises above the required operating condition temperature.

Then, in a situation where the operation of the compressor 51 should be stopped, the engagement of the magnet clutch 6 is released to disconnect the crankshaft of the internal combustion engine 100 from the compressor 51. As a result, the engine torque output by the internal combustion engine 100 is not supplied to the compressor 51, the rotation of the compressor 51 is stopped, and the refrigerant is not compressed. That is, the output of the compressor 51 is cut, that is, the discharge amount and the discharge pressure of the refrigerant by the compressor 51 are reduced as compared with the state in which the magnet clutch 6 is engaged. The situation in which the operation of the compressor 51 should be stopped is typically when the temperature of the evaporator 56 or its vicinity drops below the required cut condition temperature. If the temperature of the evaporator 56 or its vicinity is already sufficiently low, the cooling performance of the air conditioner 5 is sufficiently ensured even if the output of the compressor 51 is cut. Normally, the cut condition temperature is a lower value than the operating condition temperature.

Incidentally, when the compressor 51 is operated, unless the fuel is currently being cut or the idle stop is in progress, the ECU 0 increases the opening degree of the throttle valve 32 for the same accelerator pedal depression amount as compared with the case where the compressor 51 is not operated. It is greatly expanded to increase the amount of intake air and the amount of fuel injection filled in the cylinder 1. As a result, the engine torque output by the internal combustion engine 100 is increased to supplement the engine torque consumed by the compressor 51.

As shown in FIG. 4, the ECU 0 of the present embodiment is currently executing the fuel cut (step S2) during the deceleration running of the vehicle in which the driver does not depress the accelerator pedal (step S1). When the vehicle speed or the engine speed is higher than the predetermined value (step S3) and the predetermined time has elapsed from the time when the operation of the compressor 51 was stopped most recently (step S4), the above-mentioned operating condition temperature and cutting condition temperature The difference (hysteresis or dead zone) from the above is set smaller than the difference between the operating condition temperature and the cut condition temperature in the other case (step S5).

Specifically, if any of the conditions of steps S1 to S4 described above is not satisfied, the operating condition temperature is set to a value, for example, 3 ° C. higher than the cut condition temperature (step S6), whereas the operating condition temperature is set to a value of 3 ° C. higher than that of the cut condition temperature (step S6). If all the conditions of S4 are satisfied, the operating condition temperature is set to a value higher than the cut condition temperature by, for example, 1 ° C. (step S5). In other words, when the conditions of steps S1 to S4 are satisfied, the operating condition temperature is lowered from the operating condition temperature when the conditions are not satisfied.

FIG. 5 shows changes in the operation / stop of the compressor 51 (switching of engagement / disengagement of the clutch 6) and the temperature fluctuation of the evaporator 56 during deceleration running of the vehicle and during fuel cut. It is a representation. In FIG. 5, the square wave-like solid line MA is a pattern of switching between operation / stop of the compressor 51 when the operating condition temperature is set to a value 3 ° C. higher than the cut condition temperature F, and the square wave-like broken line MB. Is a pattern of switching between operation / stop of the compressor 51 when the operating condition temperature is set to a value 1 ° C. higher than the cut condition temperature F. Further, the sine wave-like solid line TA is the temperature of the evaporator 56 when the operating condition temperature is set to a value 3 ° C. higher than the cut condition temperature F, and the sine wave-like broken line TB is the operating condition temperature F. It is the temperature of the evaporator 56 when it is set to a value 1 ° C. higher than that.

When the operating condition temperature is changed from a value 3 ° C higher than the cut condition temperature F to a value 1 ° C higher than the cut condition temperature F and the difference between the operating condition temperature and the cut condition temperature is reduced, the frequency of switching between operation and stop of the compressor 51 increases. However, the cycle becomes shorter. At the same time, the amplitude of the temperature of the evaporator 56 becomes smaller, and the average temperature of the evaporator 56 decreases.

In FIG. 5, the square wave-like solid line E can prolong the cumulative operating time of the compressor 51 during fuel cutting by changing the operating condition temperature to a value 1 ° C. higher than the cutting condition temperature F. It shows whether or not it can be done. For example, assuming that the fuel cut condition is satisfied at the time point 0 shown in FIG. 5 and the fuel cut end condition is satisfied at the time point t1, that is, the fuel cut is executed from the time point 0 to the time point t1, the fuel cut period is assumed. The ratio of the operating time of the compressor 51 to the inside is when the operating condition temperature is 1 ° C higher than the cut condition temperature F and when the operating condition temperature is 3 ° C higher than the cut condition temperature F. Will be larger than. That is, when the vehicle is decelerating, the kinetic energy of the vehicle can be used to operate the compressor 51 for a longer time without consuming fuel, and cold heat can be stored in the evaporator 56. The fact that the square wave-like solid line E swings to the "advantageous" side means that setting the operating condition temperature to a value 1 ° C. higher than the cut condition temperature F is more advantageous in terms of efficiency. There is.

On the other hand, assuming that the fuel cut end condition is satisfied at the time point t2 shown in FIG. 5, that is, the fuel cut is executed from the time point 0 to the time point t2, the operating time of the compressor 51 occupied during the fuel cut period is The ratio is larger when the operating condition temperature is set to a value 3 ° C. higher than the cut condition temperature F than when the operating condition temperature is set to a value 1 ° C. higher than the cut condition temperature F. The fact that the square wave-like solid line E swings to the "disadvantageous" side means that setting the operating condition temperature to a value 1 ° C higher than the cut condition temperature F works more disadvantageously in terms of efficiency. There is.

Of course, if the fuel cut end condition is satisfied by the time point t0 shown in FIG. 5, that is, if the fuel cut is executed for a very short period of time but the compressor 51 is not operated during that time, it depends on the setting of the operating condition temperature. There can be no "advantage" or "disadvantage", it is a "tie".

In this way, the advantages / disadvantages of changing the operating condition temperature setting change depending on the time when the fuel cut ends, but overall, the square wave-like solid line E swings "advantageously". The former is longer in the section where the fuel is and the section where the fuel is "disadvantageous". Therefore, at the end of the fuel cut, there is a high probability that it will fall within the "advantageous" section. Further, it is basically "advantageous" from the start of executing the fuel cut until the time point t3 elapses. And, in the actual road driving in the city, most of the deceleration ends within the time point t3, and the fuel cut does not often continue beyond the time point t3. Therefore, by setting the operating condition temperature to a value 1 ° C. higher than the cut condition temperature F, the compressor 51 can be operated for a longer time during the fuel cut, and the kinetic energy of the vehicle can be efficiently recovered in the form of cold heat. Can be done.

In addition, as already mentioned, when the operating condition temperature is set to a value 1 ° C. higher than the cut condition temperature F, compared with the case where the operating condition temperature is set to a value 3 ° C. higher than the cut condition temperature F, The average temperature of the evaporator 56 during fuel cut decreases. When the vehicle is decelerating, after the fuel cut end condition is satisfied and the fuel cut is completed, the vehicle speed usually decelerates to 0 and the vehicle stops. While the vehicle is stopped, the internal combustion engine 100 is often idle-stopped. If the compressor 51 is operated during the fuel cut during deceleration and the cold heat is stored in the evaporator 56 in advance, even if the internal combustion engine 100 and the compressor 51 remain stopped due to idle stop, necessary and sufficient air conditioning (especially). , Cooling) Performance can be ensured, and the idle stop period can be extended without deteriorating the comfort of the passenger compartment. If the idle stop period can be extended, it will naturally contribute to the improvement of fuel efficiency.

In step S3, the condition that the current vehicle speed or engine speed is higher than a predetermined value is to avoid the concern that a shock (surge) may occur in the vehicle body due to the engagement or disconnection of the clutch 6. , And the noise generated by the engagement or disengagement of the clutch 6 (the clicking sound generated from the clutch 6 itself or from the relay switch on the electric circuit that energizes the magnet clutch 6) is intended to be masked by the running sound of the vehicle. ..

Further, in step S4, the condition that the predetermined time has already passed since the last stop of the operation of the compressor 51 is to appropriately suppress the frequency of engaging and disengaging the clutch 6. .. If the clutch 6 is repeatedly engaged and disconnected at an excessively high frequency, the clutch 6 may be worn and its life may be shortened, and the deterioration of NV (Noise and Vibration) performance due to the generation of noise cannot be ignored. ..

In the present embodiment, the fuel supply to the cylinder 1 of the internal combustion engine 100 is temporarily interrupted on the condition that the amount of depression of the accelerator pedal by the driver is 0 or less than the threshold value close to 0 while the vehicle is running. When the temperature of the evaporator 56 of the air conditioner 5 for air-conditioning the vehicle interior or its vicinity rises above the operating condition temperature, the clutch 6 interposed between the internal combustion engine 100 and the refrigerant compression compressor 51 At least a part of the engine torque output by the internal combustion engine 100 is supplied to the compressor 51 to operate the compressor 51, and the temperature of the evaporator 56 or its vicinity is lower than the operating condition temperature to be lower than the cut condition temperature. When the voltage drops, the clutch 6 is disengaged and the engine torque is not supplied to the compressor 51 to stop the operation of the compressor 51. The fuel is cut while the vehicle is running, and the vehicle speed or the engine rotation speed is reduced. Is higher than a predetermined value, and the difference between the operating condition temperature and the cut condition temperature when a predetermined time has elapsed from the time when the operation of the compressor 51 was stopped most recently is smaller than the difference when the temperature is not. The control device 0 of the vehicle to be set is configured.

According to the present embodiment, when the driver is decelerating without depressing the accelerator pedal, the compressor 51 is operated for a longer time without consuming fuel by using the kinetic energy of the vehicle, and cold heat is stored in the evaporator 56. be able to. The stored cold heat can be used for air conditioning in the passenger compartment later. As a result, it becomes possible to reduce the amount of fuel consumed for the operation of the compressor 51, which can contribute to the improvement of practical fuel consumption.

The present invention is not limited to the embodiment described in detail above. For example, the clutch 6 that connects the internal combustion engine 100 and the refrigerant compression compressor 51 is not limited to the magnet clutch. The clutch 6 may be driven by hydraulic pressure (hydraulic pressure) to switch between the internal combustion engine and the compressor 51.

When the conditions of steps S1 to S4 are all satisfied and the difference between the operating condition temperature and the cutting condition temperature is further reduced, in the above embodiment, the operating condition temperature is lowered without changing the cutting condition temperature. .. However, it is also conceivable to change both the operating condition temperature and the cutting condition temperature, or raise only the cutting condition temperature to reduce the difference between the operating condition temperature and the cutting condition temperature. In any case, the frequency of switching the operation / stop of the compressor 51 increases, and the cycle becomes shorter. However, since it is desirable to lower the average temperature of the evaporator 56 during fuel cut during deceleration, it is best to raise only the cut condition temperature to reduce the difference between the operating condition temperature and the cut condition temperature. not.

When the conditions of steps S1 to S4 are all satisfied and the difference between the operating condition temperature and the cutting condition temperature is further reduced, the difference is returned to the original size (according to the above embodiment, the operating condition temperature). (Returning from a value 1 ° C. higher than the cut condition temperature F to a value 3 ° C. higher) may be a time point at which the fuel cut end condition is satisfied, or a time point earlier than that. For example, when the vehicle speed or engine speed drops to a speed set slightly higher than the fuel cut return speed, the difference between the operating condition temperature and the cut condition temperature is restored to the original size. Can be done.

In addition, the specific configuration of each part, the content of the process, and the like can be variously modified without departing from the spirit of the present invention.

The present invention can be applied to the control of an internal combustion engine and an air conditioner mounted on a vehicle.

0 ... Control unit (ECU)
11 ... Injector 5 ... Air conditioner 51 ... Compressor 6 ... Magnet clutch 100 ... Internal combustion engine 103 ... Axle a ... Vehicle speed signal b ... Crank angle signal c ... Accelerator opening signal g ... Evaporator temperature signal j ... Fuel injection signal o ... Clutch Fastening signal

Claims (1)

A fuel cut is executed to temporarily suspend the fuel supply to the cylinder of the internal combustion engine, provided that the amount of depression of the accelerator pedal by the driver is 0 or less than the threshold value close to 0 while the vehicle is running.
In addition, when the temperature of the evaporator of the air conditioner that air-conditions the passenger compartment or its vicinity rises above the operating condition temperature, a clutch interposed between the internal combustion engine and the compressor for compressing the refrigerant is engaged to output the internal combustion engine. When at least a part of the engine torque is supplied to the compressor to operate the compressor and the temperature of the evaporator or its vicinity drops below the cut condition temperature lower than the operating condition temperature, the clutch is disengaged to reduce the engine torque. It does not supply to the compressor and stops the operation of the compressor.
The operating condition temperature when the fuel is cut while the vehicle is running, the vehicle speed or engine speed is higher than the specified value, and the specified time has elapsed from the time when the compressor operation was stopped most recently. A vehicle control device that sets the difference from the cut condition temperature to be smaller than the difference in other cases.

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