Vehicle air conditioning control system

Abstract

To provide an air-conditioning control system of a vehicle, which is configured so that an occupant in a vehicle interior is not aware of change in air-conditioning when an engine automatically stops during travelling of the vehicle.SOLUTION: A vehicle 1 is equipped with an engine 2 that can automatically stop under an automatic stop condition, an air conditioner 9, and a controller 60. The air conditioner has an air duct 10, heat exchange circuits 30 and 40 including heat exchangers 36 and 42 that exchange heat with air W in the air duct, and a blower 20 that blows air in the air duct to a vehicle interior 8. The controller makes volumes Qa of air blown by the blower 20 smaller than volumes Q0 of air blown by the blower at the time just before the engine automatically stops, in a no-vehicle speed air-conditioning mode Ma where a vehicle speed V of the vehicle is less than a first predetermined speed V1 at the time when the engine automatically stops, and makes reduced volumes (Q0-Qb) of the volumes Qb of air blown by the blower smaller than reduced volumes (Q0-Qa) in the no-vehicle speed air-conditioning mode, in a yes-vehicle speed air-conditioning mode Mb where a speed of the vehicle is equal to the predetermined speed or higher when the engine automatically stops.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present disclosure relates to an air conditioning control system for a vehicle.

Background Art

[0002] In order to improve the fuel efficiency of an engine, there is known a control technique for automatically stopping (idling stop) the engine when a predetermined automatic stop condition is satisfied, and automatically restarting (restart) the engine when a predetermined automatic restart condition is satisfied in the automatic stop state.

[0003] In the automatic stop state of the engine, a compressor or a pump that is driven in conjunction with the engine stops, and in the heat exchange circuit, the heat exchange medium is no longer supplied to an evaporator or a heater core as a heat exchanger, resulting in an increase in the evaporator temperature and a decrease in the heater core temperature, and a decrease in the heating and cooling capacity of the air conditioner. When the heating and cooling capacity of the air conditioner decreases, the engine has to be automatically restarted, so the fuel efficiency of the engine deteriorates.

[0004] Therefore, the vehicle control device according to Patent Document 1 predicts the parking duration at the next vehicle stop when the automatic stop condition is satisfied during traveling, calculates an evaporator temperature at which the engine is not automatically restarted during the predicted parking duration, calculates the time until the evaporator temperature reaches the above-mentioned evaporator temperature at which the engine is not automatically restarted when coasting driving is started, and executes coasting driving when the time is longer than the required parking time until the next vehicle stop.

[0005] According to such a configuration, the possibility of the engine being automatically restarted in the parking state of the vehicle is reduced, and the fuel efficiency can be improved.

Prior Art Documents

Patent Documents

[0006]

Patent Document 1

[0007] Incidentally, an air conditioner has a blower for supplying air from the air duct to the passenger compartment. When the engine is automatically stopped, a method is known to suppress the decrease in the cooling and heating capacity of the air conditioner by reducing the amount of air supplied by the blower, thereby suppressing heat exchange between the air in the air duct and the evaporator / heater core.

[0008] Even if the blower's airflow is reduced when the engine automatically shuts off while the vehicle is stopped (at no speed), vehicle vibrations and road noise are also reduced simultaneously, so it does not cause much discomfort to the occupants in the cabin.

[0009] However, if the engine automatically shuts off while the vehicle is in motion (at vehicle speed), reducing the blower's airflow can cause significant discomfort to occupants in the vehicle cabin, as there is no change in vehicle vibration or road noise, but only the blower's airflow is reduced.

[0010] This disclosure has been made in view of the above, and its purpose is to make it less likely for occupants in the vehicle to notice changes in the air conditioning when the engine automatically stops while the vehicle is in motion. [Means for solving the problem]

[0011] The vehicle air conditioning control system according to this disclosure comprises an engine that can be automatically stopped based on automatic stop conditions, an air conditioner that harmonizes the air in the passenger compartment, and a control device that controls the air conditioner, wherein the air conditioner includes an air duct through which air flows, a heat exchange circuit including a heat exchanger that performs heat exchange with the air in the air duct, and a blower that blows the air in the air duct into the passenger compartment, and the control device controls the speed of the vehicle when the engine is automatically stopped. 1. The air conditioning mode can be switched between a non-vehicle-speed air conditioning mode when the vehicle speed is below a predetermined speed and a vehicle-speed air conditioning mode when the vehicle speed is at or above the first predetermined speed when the engine is automatically stopped. The control device reduces the amount of air blown by the blower in the non-vehicle-speed air conditioning mode compared to the amount of air blown by the blower immediately before the automatic stop, and reduces the amount of air blown by the blower in the vehicle-speed air conditioning mode to be smaller than the amount of reduction in the non-vehicle-speed air conditioning mode.

[0012] Even if the blower's airflow is reduced when the engine automatically shuts off while the vehicle is stopped (at no speed), vehicle vibrations and road noise are also reduced simultaneously, so it does not cause much discomfort to the occupants in the cabin.

[0013] Therefore, in the non-vehicle-speed air conditioning mode, the blower airflow is reduced to a level lower than the blower airflow immediately before the engine automatically shuts off.

[0014] On the other hand, if the engine automatically shuts off while the vehicle is in motion (at vehicle speed), reducing the blower's airflow volume may cause significant discomfort to occupants in the vehicle cabin, as there will be no change in vehicle vibration or road noise, but only the blower's airflow volume is reduced.

[0015] Therefore, in the vehicle-speed air conditioning mode, the reduction in blower airflow is made smaller than the reduction in the non-vehicle-speed air conditioning mode. In other words, in the vehicle-speed air conditioning mode, the blower airflow is not reduced as much as possible from the blower airflow immediately before the engine automatically stops.

[0016] This can make it difficult for the passengers in the passenger compartment to notice the change in air conditioning when the engine automatically stops during the running of the vehicle. Furthermore, if the vehicle's speed reaches a second predetermined speed, which is lower than the first predetermined speed, while the vehicle's speed is in motion, the control device switches the air conditioning mode from the vehicle's speed air conditioning mode to the vehicle-in motion air conditioning mode. In the vehicle's speed air conditioning mode, the amount of air blower air is hardly reduced, so if the vehicle's speed air conditioning mode is maintained for a long time, heat exchange between the air in the air duct and the heat exchanger is promoted, which may reduce the cooling and heating capacity of the air conditioner. On the other hand, in the vehicle-in motion air conditioning mode, the amount of air blower air is reduced, so heat exchange between the air in the air duct and the heat exchanger is suppressed, and the cooling and heating capacity of the air conditioner is less likely to decrease. Therefore, by switching the air conditioning mode from the vehicle's speed air conditioning mode to the vehicle-in motion air conditioning mode when the vehicle's speed reaches a second predetermined speed, which is lower than the first predetermined speed, while the vehicle's speed is in motion, the decrease in the cooling and heating capacity of the air conditioner can be suppressed. Alternatively, the engine can be automatically restarted based on the automatic restart conditions, and the control device automatically restarts the engine in the vehicle-speed air conditioning mode based on the automatic restart conditions, which are stricter than those in the non-vehicle-speed air conditioning mode. As mentioned above, if the vehicle-speed air conditioning mode is maintained for a long period of time, heat exchange between the air in the air duct and the heat exchanger will be accelerated, which may reduce the cooling and heating capacity of the air conditioner. Therefore, in the vehicle-speed air conditioning mode, stricter automatic restart conditions are set than in the non-vehicle-speed air conditioning mode to make it easier to automatically restart the engine. This makes it possible to suppress the reduction in the cooling and heating capacity of the air conditioner caused by the automatic stopping of the engine.

[0017] In one embodiment, the control device does not reduce the air volume in the above vehicle speed air conditioning mode.

[0018] According to such a configuration, when the engine automatically stops during the running of the vehicle, it hardly gives a sense of discomfort to the passengers in the passenger compartment.

[0026] In one embodiment, the automatic restart condition includes at least one of the temperature condition of the heat exchanger and the comfort condition of the passenger compartment.

[0027] According to such a configuration, the automatic restart condition of the engine can be preferably set.

[0028] In one embodiment, the heat exchange circuit includes at least one of an evaporator and a heater core as the heat exchanger.

[0029] According to such a configuration, heat exchange with air in the air duct can be preferably performed.

[0030] In one embodiment, the vehicle includes a motor, and the vehicle is switchable between an electric mode driven only by the motor and a hybrid mode driven by at least one of the motor and the engine. In the case of the hybrid mode and the vehicle speed air conditioning mode, the vehicle runs by driving of the motor, or the vehicle is decelerating and the motor is regeneratively generating electricity.

[0031] According to such a configuration, even in the automatic stop state of the engine, the vehicle can be efficiently run.

[0032] In one embodiment, the vehicle is equipped with a motor, and the vehicle is switchable between an electric mode driven solely by the motor and a hybrid mode driven by at least one of the motor and the engine. In the electric mode, a different heat exchange circuit is used than the one used in the hybrid mode, and the non-speed air conditioning mode and the speed air conditioning mode can only be set in the hybrid mode.

[0033] With this configuration, by using different heat exchange circuits for the electric mode and the hybrid mode, suitable air conditioning control can be performed according to each operating mode. [Effects of the Invention]

[0034] According to this disclosure, it is possible to make it less likely for occupants in the vehicle to notice changes in the air conditioning when the engine automatically stops while the vehicle is in motion. [Brief explanation of the drawing]

[0035] [Figure 1] Figure 1 is a diagram showing the configuration of a vehicle air conditioning control system according to an embodiment of this disclosure. [Figure 2] Figure 2 is a flowchart showing the first half of the air conditioning control flow by the air conditioning control system. [Figure 3] Figure 3 is a flowchart showing the latter half of the air conditioning control flow by the air conditioning control system. [Figure 4] Figure 4 is a graph showing the relationship between ambient temperature and the compressor coefficient. [Figure 5] Figure 5 is a map showing the relationship between vehicle speed and air conditioning mode. [Figure 6] Figure 6 is a map showing the automatic stop and automatic restart conditions based on evaporator temperature for each air conditioning mode. [Figure 7] Figure 7 is a map showing the automatic stop and restart conditions based on the heater core temperature for each air conditioning mode. [Figure 8]Figure 8 is a map showing the automatic stop and restart conditions based on the cabin temperature for each air conditioning mode. [Figure 9] Figure 9 shows the air conditioning control time chart by the air conditioning control system. [Modes for carrying out the invention]

[0036] Embodiments of the present disclosure will be described in detail below with reference to the drawings. The following description of preferred embodiments is illustrative in nature and is not intended to limit the present disclosure, its applications, or its uses in any way.

[0037] (Vehicle configuration) Figure 1 shows an air conditioning control system S of a vehicle 1 according to an embodiment of the present disclosure. The vehicle 1 comprises an engine 2, a motor 3, a battery 4, a first clutch 5, a transmission 6, drive wheels 7, an air conditioner 9, and a controller 60 as a control device.

[0038] Vehicle 1 is a plug-in hybrid (PHEV) vehicle, and its driving mode can be switched between an electric mode (EV mode) driven solely by the motor 3, and a hybrid mode (HEV mode) driven by at least one of the motor 3 and the engine 2. The driving of Vehicle 1 by the engine 2 and the driving of Vehicle 1 by the motor 3 can be switched seamlessly.

[0039] Engine 2 is, for example, a gasoline engine. Engine 2 is capable of automatic stopping (idling stop) based on predetermined automatic stop conditions. Engine 2 is also capable of automatic restarting (restarting) based on predetermined automatic restart conditions.

[0040] Motor 3 is a synchronous motor in which permanent magnets are embedded in the rotor (rotating shaft) and stator coils are wound around the stator. Motor 3 is rotationally driven by power supplied from battery 4. Motor 3 also functions as a generator, producing electromotive force at both ends of the stator coils when the rotor is rotating due to an external force. Motor 3 generates regenerative power, for example, when vehicle 1 is decelerating.

[0041] Battery 4 is, for example, a lithium-ion battery and is rechargeable and dischargeable. Battery 4 supplies power to motor 3 by discharging. On the other hand, battery 4 is charged by the power generated by motor 3, which acts as a generator. Battery 4 can also be charged externally from an external power source via a charging plug (not shown). Although not shown, an inverter is interposed between motor 3 and battery 4.

[0042] The first clutch 5 is interposed between the engine 2 and the motor 3. The first clutch 5 connects (fastens) the output shaft of the engine 2 to the rotating shaft of the motor 3 (specifically, one end of the rotating shaft). The first clutch 5 also disconnects (releases) the output shaft of the engine 2 to the rotating shaft of the motor 3. In other words, the first clutch 5 switches between torque transmission and interruption between the engine 2 and the motor 3.

[0043] The first clutch 5 is, for example, a dry multi-plate clutch, and its transmission torque capacity can be changed by continuously or stepwise changing the flow rate and pressure of the clutch hydraulic fluid from an oil pump (not shown).

[0044] When the first clutch 5 is engaged, if either the output shaft of the engine 2 or the rotation shaft of the motor 3 rotates, the other also rotates. When the first clutch 5 is disengaged, even if one of the output shaft of the engine 2 or the rotation shaft of the motor 3 rotates, the other does not rotate.

[0045] The transmission 6 changes the speed of the power from the engine 2 and / or motor 3 and outputs it to the drive wheels 7. The transmission 6, although not shown in detail in the illustrations, includes a planetary gear mechanism, a brake mechanism, and a second clutch 6a. The second clutch 6a is, for example, a dry multi-plate clutch that switches between transmitting and disconnecting torque between the engine 2 and / or motor 3 and the drive wheels 7.

[0046] In hybrid mode, the first clutch 5 and the second clutch 6a are basically both engaged, and the engine 2 drives the drive wheels 7 (moves the vehicle 1) via the motor 3 and the transmission 6.

[0047] In hybrid mode, the motor 3 may act as an assist motor, assisting the engine 2 in driving the drive wheels 7 by driving the motor 3 while the engine 2 is driving the drive wheels 7.

[0048] In hybrid mode, the drive wheels 7 may be driven solely by the engine 2, without using the motor 3 as an assist motor. Alternatively, the engine 2 may be used to power the motor 3, which acts as a generator.

[0049] In hybrid mode, the drive wheels 7 may be driven by the motor 3 alone without driving the engine 2 (vehicle 1 may be driven). Here, if the first clutch 5 is engaged, the engine 2 will rotate in conjunction with the rotation of the motor 3, even though the engine 2 itself is not driving (combusting). On the other hand, if the first clutch 5 is disengaged, the engine 2 will not rotate even if the motor 3 rotates.

[0050] In hybrid mode, motor 3 may regenerate power while vehicle 1 is decelerating.

[0051] In electric mode, the first clutch 5 is disengaged and the second clutch 6a is engaged, and the drive wheels 7 are driven via the transmission 6 by the motor 3 alone.

[0052] (Air conditioner) The air conditioner 9 harmonizes the air W in the passenger compartment 8. The air conditioner 9 includes an air duct 10, a blower 20, a refrigerant circulation circuit 30 as a heat exchange circuit, an engine coolant circulation circuit 40 as a heat exchange circuit, and a hot water circulation circuit 50 as a heat exchange circuit.

[0053] The air duct 10 forms an air passage for introducing air W into the passenger compartment 8. Air W flows through the air duct 10. An outside air inlet 11 and an inside air inlet 12 are provided at the upstream end of the air duct 10. Outside air W (outside air) from outside the passenger compartment 8 is introduced into the air duct 10 via the outside air inlet 11. Inside air W (inside air) from inside the passenger compartment 8 is introduced into the air duct 10 via the inside air inlet 12.

[0054] A switching door 13 is located near the outside air inlet 11 and the inside air inlet 12. The switching door 13 is driven by an actuator (not shown) to switch between an outside air intake mode, in which outside air is introduced into the air duct 10 from the outside air inlet 11, and an inside air intake mode, in which inside air is introduced into the air duct 10 from the inside air inlet 12.

[0055] An air outlet 14 is provided at the downstream end of the air duct 10. The air outlet 14 communicates with the passenger compartment 8 and blows the air W inside the air duct 10 into the passenger compartment 8. There are multiple air outlets 14. A door 15 that opens and closes the air outlet 14 is located near the air outlet 14. The door 15 is opened and closed by an actuator (not shown).

[0056] Multiple air vents 14 include, for example, a defroster vent that blows air W toward the inner surface of the windshield, a face vent that blows air W toward the occupant's head or chest, and a foot vent that blows air W toward the occupant's legs.

[0057] Blower 20 is a centrifugal blower and is located on the upstream side of the air duct 10. Blower 20 blows air W from the air duct 10 into the passenger compartment 8. Blower 20 has an impeller 21 and a blower motor 22 that rotates the impeller 21. The definition of blower 20 includes all blowing devices that blow air W, regardless of the magnitude of the discharge pressure.

[0058] The amount of air W supplied by the blower 20 is controlled by controlling the rotational speed of the impeller 21 using the blower motor 22. The blower motor 22 is connected to a blower drive circuit (not shown) which includes an inverter.

[0059] The refrigerant circulation circuit 30 cools the air W flowing through the air duct 10 by circulating the refrigerant, thereby cooling the passenger compartment 8. The refrigerant circulation circuit 30 includes an electric compressor 31, a condenser 32, a cooling fan 33, a receiver 34, an expansion valve 35, an evaporator 36 acting as a heat exchanger, and refrigerant piping 37.

[0060] The electric compressor 31 compresses and discharges the inhaled refrigerant. The electric compressor 31 is electrically powered and operates independently of the engine 2. That is, the electric compressor 31 can be driven even when the engine 2 is in an automatic stop state. The operation of the electric compressor 31 causes the refrigerant to circulate through the refrigerant circulation circuit 30.

[0061] The refrigerant discharged from the electric compressor 31 flows into the condenser 32. The condenser 32 condenses and liquefies the refrigerant compressed by the electric compressor 31. The condenser 32 performs heat exchange between the refrigerant and the airflow from the cooling fan 33 and / or the airflow from the vehicle.

[0062] The receiver 34 separates the refrigerant condensed and liquefied by the condenser 32 into gas and liquid phases, allowing only the liquid refrigerant to flow downstream. The expansion valve 35 depressurizes and expands the liquid refrigerant separated by the receiver 34.

[0063] The evaporator 36 is located inside the air duct 10. The evaporator 36 evaporates the refrigerant that has been depressurized and expanded by the expansion valve 35. The evaporator 36 exchanges heat with the air W in the air duct 10. Specifically, the evaporator 36 cools the air W in the air duct 10 by evaporating the refrigerant.

[0064] The refrigerant piping 37 connects the electric compressor 31, condenser 32, receiver 34, expansion valve 35, and evaporator 36 in a ring shape.

[0065] The engine coolant circulation circuit 40 circulates engine coolant. The engine coolant is heated by circulating through various parts of the engine 2. The engine coolant circulation circuit 40 heats the air W flowing through the air duct 10 by circulating the heated engine coolant, thereby heating the passenger compartment 8.

[0066] Engine 2 is equipped with an engine coolant temperature sensor 2a. The engine coolant temperature sensor 2a measures the temperature of the engine coolant circulating in various parts of engine 2.

[0067] The engine coolant circulation circuit 40 includes a water pump 41, a heater core 42 as a heat exchanger, and engine coolant piping 43.

[0068] The water pump 41 is a mechanical pump that discharges engine coolant. The water pump 41 is connected to the crankshaft of the engine 2 via a pulley and a timing belt, etc. That is, the water pump 41 is driven in conjunction with the engine 2. The water pump 41 does not drive when the engine 2 is in an automatic stop state. When the engine 2 is in an automatic stop state, the engine coolant does not circulate in the engine coolant circulation circuit 40.

[0069] The heater core 42 is located downstream of the evaporator 36 within the air duct 10. Engine coolant discharged from the water pump 41 flows into the heater core 42. The heater core 42 exchanges heat with the air W in the air duct 10. Specifically, the heater core 42 heats the air W in the air duct 10 as a heat source.

[0070] The engine coolant piping 43 connects the water pump 41 and the heater core 42 in a ring shape. The engine coolant circulation circuit 40 also includes a radiator and the like for releasing the heat from the engine coolant into the atmosphere.

[0071] The hot water circulation circuit 50 heats the air W flowing through the air duct 10 by circulating hot water, thereby heating the passenger compartment 8. The hot water circulation circuit 50 includes an electric pump 51, a heater 52, hot water piping 53, and the aforementioned heater core 42.

[0072] The electric pump 51 discharges the medium. The electric pump 51 is electrically powered and operates independently of the engine 2. The electric pump 51 drives the medium through the hot water circulation circuit 50. The heater 52 heats the medium discharged from the electric pump 51 to make hot water.

[0073] Hot water heated by the heater 52 flows into the heater core 42. The heater core 42 acts as a heat source, exchanging heat with the air W in the air duct 10 to heat the air W in the air duct 10. The hot water piping 53 connects the electric pump 51, the heater 52, and the heater core 42 in a ring shape.

[0074] In hybrid mode, the refrigerant circulation circuit 30 and the engine coolant circulation circuit 40 are used. In electric mode, the refrigerant circulation circuit 30 and the hot water circulation circuit 50 are used.

[0075] In the air duct 10, an air mix door 16 is positioned between the evaporator 36 and the heater core 42. The air mix door 16 rotates between a maximum cooling position, where all the air W bypasses the heater core 42, and a maximum heating position, where all the air W passes through the heater core 42, driven by an actuator (not shown). By changing the ratio of air W that bypasses the heater core 42 to air W that passes through the heater core 42, the outlet temperature of the air W blown from the air outlet 14 into the passenger compartment 8 is adjusted.

[0076] (Air conditioning control system) The controller 60 is a well-known microcomputer-based controller. The controller 60 is composed of a computer, and although not shown in the diagram, it includes a processor (e.g., CPU) and memory such as ROM or RAM. The memory stores various programs and data that are interpreted and executed on the processor. The controller 60 has the function of controlling the power unit of the vehicle 1 and the function of controlling the air conditioner 9.

[0077] The controller 60 outputs control signals to the engine 2, inverter (not shown), first clutch 5, and transmission 6 (second clutch 6a). For example, the controller 60 adjusts the rotational speed and torque of the engine 2 by controlling the spark plug, fuel injector, throttle valve, etc. of the engine 2.

[0078] The controller 60 controls the first clutch 5 and the transmission 6 (second clutch 6a) via a hydraulic control circuit. The controller 60 also controls the motor 3 via an inverter to adjust the rotational speed and torque of the motor 3.

[0079] The controller 60 controls the air conditioner 9. Specifically, the controller 60 outputs control signals to the switching door 13, opening / closing door 15, air mix door 16, blower motor 22, electric compressor 31, cooling fan 33, electric pump 51, and heater 52 of the air conditioner 9.

[0080] The controller 60 controls the actuators for driving the switching door 13, the opening / closing door 15, and the air mix door 16 to adjust the position of each door 13, 15, and 16. The controller 60 also controls the rotation speed of the impeller 21 by controlling the blower motor 22 to adjust the amount of air W supplied by the blower 20.

[0081] The controller 60 controls the amount of refrigerant circulating in the refrigerant circulation circuit 30 (the amount of refrigerant flowing into the evaporator 36) by controlling the rotation speed of the electric compressor 31. The controller 60 controls the amount of hot water circulating in the hot water circulation circuit 50 (the amount of hot water flowing into the heater core 42) by controlling the rotation speed of the electric pump 51. The controller 60 may also control the rotation speed of the cooling fan 33 and the ON / OFF status of the heater 52.

[0082] The controller 60 automatically stops the engine 2 based on predetermined automatic stop conditions. The controller 60 automatically restarts the engine 2 based on predetermined automatic restart conditions. The automatic stop conditions and automatic restart conditions are stored in the controller 60 in advance. There are various conditions for the automatic stop conditions and automatic restart conditions, and examples of air conditioning-related conditions include the temperature conditions of the heat exchanger (evaporator 36 and heater core 42) and / or the comfort conditions of the passenger compartment 8 (temperature conditions, etc.).

[0083] (Air conditioning mode) The controller 60 can switch the air conditioning mode between a non-vehicle-speed air conditioning mode Ma and a vehicle-speed air conditioning mode Mb. The non-vehicle-speed air conditioning mode Ma is the mode used when the vehicle speed V is less than a first predetermined speed V1 when the engine 2 is automatically stopped. The vehicle-speed air conditioning mode Mb is the mode used when the vehicle speed V is equal to or greater than the first predetermined speed V1 when the engine 2 is automatically stopped. The first predetermined speed V1 can be set as appropriate and is stored in the controller 60 in advance. The first predetermined speed V1 is, for example, 5 km / h. The vehicle speed V is measured by a vehicle speed sensor.

[0084] In the engine-off air-conditioning mode Ma, the controller 60 reduces the air flow rate Qa of the air W by the blower 20 (Qa < Q0) compared to the air flow rate Q0 of the air W by the blower 20 immediately before the automatic stop of the engine 2. In other words, in the engine-off air-conditioning mode Ma, the controller 60 makes the rotational speed of the blower motor 22 (impeller 21) smaller than the rotational speed of the blower motor 22 immediately before the automatic stop of the engine 2.

[0085] "Immediately before the automatic stop of the engine 2" may include the moment (0 seconds before) of the automatic stop of the engine 2, or up to about 5 seconds before the automatic stop of the engine 2.

[0086] In the vehicle-speed air-conditioning mode Mb, the controller 60 does not reduce the air flow rate Qb of the air W by the blower 20 (Qb = Q0). That is, in the vehicle-speed air-conditioning mode Mb, the controller 60 makes the reduction amount (Q0 - Qb) of the air flow rate Qb of the air W by the blower 20 smaller than the reduction amount (Q0 - Qa) of the air flow rate Qa of the air W by the blower 20 in the engine-off air-conditioning mode Ma (Q0 - Qb < Q0 - Qa).

[0087] In other words, in the vehicle-speed air-conditioning mode Mb, the controller 60 does not reduce the rotational speed of the blower motor 22 (impeller 21). The controller 60 makes the reduction amount of the rotational speed of the blower motor 22 in the vehicle-speed air-conditioning mode Mb smaller than the reduction amount of the rotational speed of the blower motor 22 in the engine-off air-conditioning mode Ma.

[0088] When the speed V of the vehicle 1 reaches a second predetermined speed V2 smaller than the first predetermined speed V1 (V = V2) during the progress of the vehicle-speed air-conditioning mode Mb, the controller 60 switches the air-conditioning mode from the vehicle-speed air-conditioning mode Mb to the engine-off air-conditioning mode Ma. The second predetermined speed V2 can be set as appropriate and is stored in the controller 60 in advance. The second predetermined speed V2 is, for example, 0 km / h.

[0089] Even if the speed V of the vehicle 1 falls below the first predetermined speed V1 (e.g., 3 km / h) while the vehicle speed air conditioning mode Mb is in progress, the controller 60 maintains the air conditioning mode in the vehicle speed air conditioning mode Mb until the speed V of the vehicle 1 reaches the second predetermined speed V2 (e.g., 0 km / h).

[0090] For example, when vehicle 1 approaches a downhill slope, if the speed V of vehicle 1 reaches a first predetermined speed V1 while in motionless air conditioning mode Ma, the controller 60 switches the air conditioning mode from motionless air conditioning mode Ma to motion-controlled air conditioning mode Mb.

[0091] In the vehicle-speed air conditioning mode Mb, the controller 60 automatically restarts the engine 2 based on an automatic restart condition Yb that is stricter than the automatic restart condition Ya in the non-vehicle-speed air conditioning mode Ma. As described above, the automatic restart conditions Ya and Yb include the temperature conditions of the heat exchanger (evaporator 36 and heater core 42) and / or the comfort conditions (temperature conditions, etc.) of the passenger compartment 8.

[0092] Similarly, in the vehicle-speed air conditioning mode Mb, the controller 60 can automatically shut down the engine 2 based on an automatic shut-off condition Xb that is stricter than the automatic shut-off condition Xa in the non-vehicle-speed air conditioning mode Ma. As mentioned above, the automatic shut-off conditions Xa and Xb include the temperature conditions of the heat exchanger (evaporator 36 and heater core 42) and / or the comfort conditions (temperature conditions, etc.) of the passenger compartment 8.

[0093] In hybrid mode and with vehicle-speed air conditioning mode Mb, vehicle 1 is driven solely by motor 3, or vehicle 1 is decelerating and motor 3 is generating regenerative power.

[0094] In electric mode, a different hot water circulation circuit 50 is used than the engine coolant circulation circuit 40 used in hybrid mode.

[0095] The non-speed-controlled air conditioning mode Ma and the speed-controlled air conditioning mode Mb can only be set in hybrid mode. In other words, the non-speed-controlled air conditioning mode Ma and the speed-controlled air conditioning mode Mb are not available in electric mode.

[0096] (Air conditioning control flow) Figures 2 and 3 are flowcharts illustrating the air conditioning control flow by the air conditioning control system S. Figure 2 shows the first half, and Figure 3 shows the second half. The air conditioning control flow shown in Figures 2 and 3 mainly illustrates the case where the passenger compartment 8 is cooled (cooling scene).

[0097] Starting from the beginning, in step S1, the target rotational speed Nc1 of the electric compressor 31 in the refrigerant circulation circuit 30 is set. The rotational speed Nc of the electric compressor 31 is related to the outlet temperature of the air W into the passenger compartment 8. That is, the larger the rotational speed Nc of the electric compressor 31, the larger the amount of refrigerant circulated in the refrigerant circulation circuit 30, so the cooling capacity of the air W by the evaporator 36 increases, and the outlet temperature of the air W into the passenger compartment 8 decreases.

[0098] The target rotational speed Nc1 is determined based on the humidity of the outside air and the temperature and humidity of the vehicle interior 8. The target rotational speed Nc1 may not be set each time, but may be uniquely determined and stored in the controller 60.

[0099] Next, in step S2, the operating mode of vehicle 1 is determined. If the operating mode of vehicle 1 is determined to be hybrid mode (HEV mode), the process proceeds to step S3. If the operating mode of vehicle 1 is determined to be electric mode (EV mode), the process proceeds to step S23, where normal air conditioning control is performed using the refrigerant circulation circuit 30 and the hot water circulation circuit 50, and the process returns to the previous state.

[0100] If vehicle 1 is in hybrid mode (HEV mode), in step S3, the automatic stop conditions Xa and Xb for engine 2 are determined.

[0101] Next, in step S4, it is determined whether the first clutch 5 is in a disengaged state or a engaged state. If the first clutch 5 is in a disengaged state, the engine 2 will not rotate even if the motor 3 rotates. In other words, if the first clutch 5 is in a disengaged state, it can be determined that the rotational speed Ne of the engine 2 is less than a predetermined rotational speed Ne1. At this time, it can be determined that the engine 2 is in an automatic stop (idling stop) state.

[0102] On the other hand, when the first clutch 5 is engaged, the engine 2 rotates in conjunction with the rotation of the motor 3. That is, when the first clutch 5 is engaged, it can be determined that the rotational speed Ne of the engine 2 is equal to or greater than a predetermined rotational speed Ne1. The predetermined rotational speed Ne1 can be set as appropriate, for example, 500 rpm.

[0103] If it is determined in step S4 that the first clutch 5 is in a disengaged state (engine 2 rotational speed Ne is less than a predetermined rotational speed Ne1), the process proceeds to step S5. If it is determined in step S4 that the first clutch 5 is in a engaged state (engine 2 rotational speed Ne is equal to or greater than a predetermined rotational speed Ne1), the process proceeds to step S6.

[0104] In step S5, the water pump 41, which is linked to the engine 2, is not driven, so the engine coolant does not circulate through the engine coolant circulation circuit 40 and does not flow into the heater core 42. In other words, the temperature Th of the heater core 42 does not match the engine coolant temperature Te measured by the engine coolant temperature sensor 2a (Th ≠ Te).

[0105] Therefore, in step S5, the measured temperature Te of the engine coolant cannot be used directly as the temperature Th of the heater core 42. Thus, the temperature Th of the heater core 42 is predicted based on a temperature prediction model or the like, under conditions where engine coolant does not flow into the heater core 42.

[0106] In step S6, the water pump 41 is driven in conjunction with the rotation of the engine 2, so the engine coolant circulates through the engine coolant circulation circuit 40 and flows into the heater core 42. That is, the temperature Th of the heater core 42 matches the measured temperature Te of the engine coolant by the engine coolant temperature sensor 2a (Th = Te). Therefore, in step S6, the measured temperature Te of the engine coolant can be used directly as the temperature Th of the heater core 42.

[0107] After step S5, in step S7, air mix air conditioning control is performed using the refrigerant circulation circuit 30 and the engine coolant circulation circuit 40. When the air mix door 16 is in the maximum cooling position during air mix air conditioning control, all the air W bypasses the heater core 42.

[0108] Similarly, after step S6, in step S7', air mix air conditioning control is performed using the refrigerant circulation circuit 30 and the engine coolant circulation circuit 40. After step S7', the return process is initiated.

[0109] Next, in step S8, the level of cooling requirement is determined. The cooling requirement is determined mainly based on the outside air temperature Tm. If the outside air temperature Tm is high, the cooling requirement is high, and if the outside air temperature Tm is not so high, the cooling requirement is low. The threshold for the outside air temperature Tm that serves as the basis for determining the level of cooling requirement can be set as appropriate, for example, 25°C.

[0110] If it is determined in step S8 that the cooling requirement is low, proceed to step S9. If it is determined in step S8 that the cooling requirement is high, proceed to step S10.

[0111] In step S9, if the rotational speed Nc of the electric compressor 31 is increased despite the low cooling requirement, the air W will be overcooled by the evaporator 36. This necessitates reheating the air W with the heater core 42, which is inefficient.

[0112] Therefore, in step S9, the rotational speed Nc of the electric compressor 31 is set to its upper limit rotational speed Nc max The value obtained by multiplying by the compressor coefficient k (0 ≤ k ≤ 1) and the target rotational speed Nc1 are the smaller of these two values. That is, Nc = Min(Nc max ×k,Nc1) is the upper limit of rotational speed Nc max This is the maximum rotational speed that the electric compressor 31 can achieve. Note that the upper limit rotational speed Nc max Alternatively, the rated rotational speed may be used.

[0113] The compressor coefficient k is determined based on the ambient temperature Tm. Figure 4 is a graph showing the relationship between the ambient temperature Tm [°C] and the compressor coefficient k. When the ambient temperature Tm is 20°C or less, the compressor coefficient k is constant at 0. When the ambient temperature Tm is 30°C or higher, the compressor coefficient k is constant at 1. When the ambient temperature Tm is between 20°C and 30°C, the compressor coefficient k changes between 0 and 1 in proportion to the ambient temperature Tm. When the compressor coefficient k is 0, the rotational speed Nc of the electric compressor 31 is zero (the electric compressor 31 does not rotate).

[0114] On the other hand, in step S10, since the cooling requirement is high, the compressor coefficient k is not used in order to promote the cooling of the air W by the evaporator 36. In step S10, the rotational speed Nc of the electric compressor 31 is set to its upper limit rotational speed Nc max The smaller of the target rotation speed Nc1 is used. That is, Nc = Min(Nc max ,Nc1)

[0115] After steps S9 and S10, in step S11, it is determined whether the speed V of vehicle 1 is equal to or greater than the first predetermined speed V1 (5 km / h). Figure 5 is a map showing the relationship between the speed V of vehicle 1 and the air conditioning mode.

[0116] As shown in FIGS. 3 and 5, when the speed V of the vehicle 1 is greater than or equal to the first predetermined speed V1 (V≧V1), the process proceeds to step S12, and the air-conditioning mode is set to the vehicle-speed air-conditioning mode Mb. When the speed V of the vehicle 1 is less than the first predetermined speed V1 (V<V1), the process proceeds to step S13, and the air-conditioning mode is set to the non-vehicle-speed air-conditioning mode Ma. In addition, the white circles in FIG. 5 indicate the speed V of the vehicle 1 at the moment of automatic stop of the engine 2.

[0117] In the vehicle-speed air-conditioning mode Mb, in step S14, the air volume Qb of the air W blown by the blower 20 is not reduced from the air volume Q0 immediately before the automatic stop of the engine 2 (Qb = Q0, blower air volume reduction = NO).

[0118] On the other hand, in the non-vehicle-speed air-conditioning mode Ma, in step S15, the air volume Qa of the air W blown by the blower 20 is reduced compared to the air volume Q0 immediately before the automatic stop of the engine 2 (Qa < Q0, blower air volume reduction = YES).

[0119] That is, the reduction amount (Q0 - Qb) of the air volume Qb of the blower 20 in the vehicle-speed air-conditioning mode Mb is smaller than the reduction amount (Q0 - Qa) of the air volume Qa of the blower 20 in the non-vehicle-speed air-conditioning mode Ma (Q0 - Qb < Q0 - Qa).

[0120] FIG. 6 is a map showing the automatic stop conditions Xa, Xb and the automatic restart conditions Ya, Yb based on the temperature Tv [°C] of the evaporator 36 for each of the air-conditioning modes Ma, Mb. The upper part of FIG. 6 is the "vehicle-speed evaporator temperature map", which shows the automatic stop condition Xb and the automatic restart condition Yb based on the temperature Tv of the evaporator 36 in the vehicle-speed air-conditioning mode Mb. The lower part of FIG. 6 is the "non-vehicle-speed evaporator temperature map", which shows the automatic stop condition Xa and the automatic restart condition Ya based on the temperature Tv of the evaporator 36 in the non-vehicle-speed air-conditioning mode Ma.

[0121] When the vehicle speed air conditioning mode Mb is selected, in step S16, the "vehicle speed evaporator temperature map" is referenced to determine whether or not to automatically restart the engine 2 based on the temperature Tv of the evaporator 36 as the automatic restart condition Yb. On the other hand, when the vehicle speed air conditioning mode Mb is selected, in step S17, the "vehicle speed evaporator temperature map" is referenced to determine whether or not to automatically restart the engine 2 based on the temperature Tv of the evaporator 36 as the automatic restart condition Ya.

[0122] As shown in the upper part of Figure 6, in the vehicle speed air conditioning mode Mb, when the temperature Tv of the evaporator 36, which is the automatic restart condition Yb, reaches 12°C or higher, the engine 2 automatically restarts. After the engine 2 automatically restarts, when the temperature Tv of the evaporator 36, which is the automatic stop condition Xb, falls below 8°C, the engine 2 can be automatically stopped.

[0123] As shown in the lower part of Figure 6, in the non-vehicle-speed air conditioning mode Ma, when the temperature Tv of the evaporator 36, which is the automatic restart condition Ya, reaches 16°C or higher, the engine 2 automatically restarts. After the engine 2 automatically restarts, when the temperature Tv of the evaporator 36, which is the automatic stop condition Xa, falls below 12°C, the engine 2 can be automatically stopped.

[0124] As shown in Figure 6, the temperature Tv (12°C) of the evaporator 36 as the automatic restart condition Yb in the vehicle-speed air conditioning mode Mb is lower (more severe) than the temperature Tv (16°C) of the evaporator 36 as the automatic restart condition Ya in the non-vehicle-speed air conditioning mode Ma. Similarly, the temperature Tv (8°C) of the evaporator 36 as the automatic stop condition Xb in the vehicle-speed air conditioning mode Mb is lower (more severe) than the temperature Tv (12°C) of the evaporator 36 as the automatic stop condition Xa in the non-vehicle-speed air conditioning mode Ma. The white circles in Figure 6 indicate the temperature Tv of the evaporator 36 at the moment of automatic engine 2 stop.

[0125] Figure 7 is a map showing the automatic stop conditions Xa, Xb and automatic restart conditions Ya, Yb based on the heater core temperature Th [°C] for each air conditioning mode Ma, Mb. The upper part of Figure 7 is the "heater core temperature map with vehicle speed," showing the automatic stop conditions Xb and automatic restart conditions Yb based on the heater core temperature Th in the air conditioning mode Mb with vehicle speed. The lower part of Figure 7 is the "heater core temperature map without vehicle speed," showing the automatic stop conditions Xa and automatic restart conditions Ya based on the heater core temperature Th in the air conditioning mode Ma without vehicle speed.

[0126] When the vehicle speed air conditioning mode Mb is selected, in step S18, the "vehicle speed heater core temperature map" is referenced to determine whether or not to automatically restart the engine 2 based on the temperature Th of the heater core 42 as the automatic restart condition Yb. On the other hand, when the vehicle speed air conditioning mode Mb is selected, in step S19, the "vehicle speed heater core temperature map" is referenced to determine whether or not to automatically restart the engine 2 based on the temperature Th of the heater core 42 as the automatic restart condition Ya.

[0127] As shown in the upper part of Figure 7, in the vehicle speed air conditioning mode Mb, when the temperature Th of the heater core 42, which is the automatic restart condition Yb, falls below 50°C, the engine 2 automatically restarts. After the engine 2 automatically restarts, when the temperature Th of the heater core 42, which is the automatic stop condition Xb, rises to 55°C or higher, the engine 2 becomes capable of automatically stopping.

[0128] As shown in the lower part of Figure 7, in the non-vehicle-speed air conditioning mode Ma, when the temperature Th of the heater core 42, which is the automatic restart condition Ya, falls below 45°C, the engine 2 automatically restarts. After the engine 2 automatically restarts, when the temperature Th of the heater core 42, which is the automatic stop condition Xa, rises to 50°C or higher, the engine 2 becomes capable of automatically stopping.

[0129] As shown in Figure 7, the temperature Th (50°C) of the heater core 42 as the automatic restart condition Yb in the vehicle-speed air conditioning mode Mb is higher (more severe) than the temperature Th (45°C) of the heater core 42 as the automatic restart condition Ya in the vehicle-speed air conditioning mode Ma. Similarly, the temperature Th (55°C) of the heater core 42 as the automatic stop condition Xb in the vehicle-speed air conditioning mode Mb is higher (more severe) than the temperature Th (50°C) of the heater core 42 as the automatic stop condition Xa in the vehicle-speed air conditioning mode Ma. The white circles in Figure 7 indicate the temperature Th of the heater core 42 at the moment of automatic engine 2 shutdown.

[0130] Figure 8 is a map showing the automatic stop conditions Xa, Xb and automatic restart conditions Ya, Yb based on the temperature Tr [°C] of the vehicle compartment 8 for each air conditioning mode Ma, Mb. The temperature Tr of the vehicle compartment 8 is one of the comfort conditions for the vehicle compartment 8. In this example, the closer the temperature Tr of the vehicle compartment 8 is to 25°C, the higher the comfort level of the vehicle compartment 8 is set to be.

[0131] The upper part of Figure 8 is the "Vehicle Speed ​​Cabin Temperature Map," which shows the automatic stop condition Xb and automatic restart condition Yb based on the temperature Tr of the cabin 8 in the vehicle speed air conditioning mode Mb. The lower part of Figure 8 is the "Vehicle Speed ​​Non-Vehicle Cabin Temperature Map," which shows the automatic stop condition Xa and automatic restart condition Ya based on the temperature Tr of the cabin 8 in the non-vehicle speed air conditioning mode Ma.

[0132] When the vehicle is in speed-sensitive air conditioning mode Mb, in step S20, the system refers to the "vehicle-sensitive cabin temperature map" and determines whether or not to automatically restart the engine 2 based on the cabin temperature Tr of the cabin 8 as the automatic restart condition Yb. On the other hand, when the vehicle is not in speed-sensitive air conditioning mode Mb, in step S21, the system refers to the "vehicle-not-speed cabin temperature map" and determines whether or not to automatically restart the engine 2 based on the cabin temperature Tr of the cabin 8 as the automatic restart condition Ya.

[0133] As shown in the upper part of Figure 8, in the vehicle speed air conditioning mode Mb, when the temperature Tr of the passenger compartment 8, which is the automatic restart condition Yb, falls below 15°C or exceeds 35°C, the engine 2 automatically restarts. After the engine 2 automatically restarts, when the temperature Tr of the passenger compartment 8, which is the automatic stop condition Xb, falls below 20°C or exceeds 30°C, the engine 2 can be automatically stopped.

[0134] As shown in the lower part of Figure 8, in the non-vehicle-speed air conditioning mode Ma, when the temperature Tr of the passenger compartment 8, which is the automatic restart condition Ya, falls below 10°C or exceeds 40°C, the engine 2 automatically restarts. After the engine 2 automatically restarts, when the temperature Th of the passenger compartment 8, which is the automatic stop condition Xa, falls below 15°C or exceeds 35°C, the engine 2 can be automatically stopped.

[0135] As shown in Figure 8, the temperature Tr (15°C to 35°C) of the cabin 8 as the automatic restart condition Yb in the vehicle-speed air conditioning mode Mb is closer to 25°C and has a narrower (stricter) tolerance range than the temperature Tr (10°C to 40°C) of the cabin 8 as the automatic restart condition Ya in the vehicle-speed air conditioning mode Ma. Similarly, the temperature Tr (20°C to 30°C) of the cabin 8 as the automatic stop condition Xb in the vehicle-speed air conditioning mode Mb is closer to 25°C and has a narrower (stricter) tolerance range than the temperature Tr (15°C to 35°C) of the cabin 8 as the automatic stop condition Xa in the vehicle-speed air conditioning mode Ma. The white circles in Figure 8 indicate the temperature Tr of the cabin 8 at the moment of automatic engine 2 stop.

[0136] When the vehicle speed-activated air conditioning mode Mb is selected, after step S20, in step S22, it is determined whether the vehicle speed V of vehicle 1 has reached the second predetermined speed V2 (=0 km / h). If the vehicle speed V of vehicle 1 does not reach the second predetermined speed V2 (V>V2), the process returns. If the vehicle speed V of vehicle 1 has reached the second predetermined speed V2 (=0 km / h) (V=V2=0 km / h), the process proceeds to step S13, and the air conditioning mode switches from the vehicle speed-activated air conditioning mode Mb to the non-vehicle speed-activated air conditioning mode Ma. When the non-vehicle speed-activated air conditioning mode Ma is selected, the process returns after step S21.

[0137] (Air conditioning control time chart) Figure 9 shows the air conditioning control time chart by the air conditioning control system S. In Figure 9, the vehicle speed V, engine speed Ne of the engine 2, electric compressor speed Nc of the electric compressor 31, evaporator temperature Tv of the evaporator 36, heater core temperature Th of the heater core 42, and blower voltage U of the blower 20 are shown. Note that Figure 9 illustrates a heating scenario.

[0138] At time t1, the speed V of vehicle 1 is equal to or greater than the first predetermined speed V1 (5 km / h). Since engine 2 is rotating, the temperature Th of heater core 42 is maintained at a high level. Since electric compressor 31 is rotating, the temperature Tv of evaporator 36 is maintained at a low level. The voltage U of blower 20 is ON (blower motor 22 starts and impeller 21 rotates). In other words, heat exchange between the air W in air duct 10 and the heat exchanger (evaporator 36 and heater core 42) is promoted.

[0139] At time t2, engine 2 automatically stops, and the rotational speed Ne of engine 2 becomes zero. At the moment engine 2 automatically stops (time t2), the speed V of vehicle 1 is greater than or equal to the first predetermined speed V1. That is, the vehicle speed air conditioning mode Mb is applied. The speed V of vehicle 1 begins to decrease. Motor 3 may regenerate power during the deceleration of vehicle 1. Since the rotational speed Ne of engine 2 is zero, the temperature Th of heater core 42 begins to decrease. Electric compressor 31 is stopped. Since the rotational speed Nc of electric compressor 31 is zero, the temperature Tv of evaporator 36 begins to rise. Since the vehicle speed air conditioning mode Mb is applied, the voltage U of blower 20 is maintained ON.

[0140] At time t3, the temperature Th of the heater core 42 falls below the lower limit temperature Thb (e.g., 50°C) defined by the automatic restart condition Yb in the vehicle speed air conditioning mode Mb. Therefore, the engine 2 is automatically restarted and rotated. The speed V of the vehicle 1 decreases over time. As the engine 2 rotates, the temperature Th of the heater core 42 begins to rise. The electric compressor 31 rotates again. As the electric compressor 31 rotates, the temperature Tv of the evaporator 36 begins to decrease. The voltage U of the blower 20 is maintained ON.

[0141] At time t4, engine 2 is automatically stopped, and its rotational speed Ne is set to zero. At the moment engine 2 is automatically stopped (time t4), the speed V of vehicle 1 is greater than or equal to the first predetermined speed V1. That is, the vehicle speed air conditioning mode Ma is applied. The speed V of vehicle 1 decreases over time. Motor 3 may regenerate power during the deceleration of vehicle 1. Since the rotational speed Ne of engine 2 is zero, the temperature Th of heater core 42 begins to decrease. Electric compressor 31 is stopped. Since the rotational speed Nc of electric compressor 31 is zero, the temperature Tv of evaporator 36 begins to rise. Since the vehicle speed air conditioning mode Ma is applied, the voltage U of blower 20 is maintained ON.

[0142] At time t5, engine 2 remains in the automatic stop state, and the rotational speed Ne of engine 2 remains zero. The speed V of vehicle 1 reaches the second predetermined speed V2 (0 km / h). That is, the air conditioning mode switches from the vehicle speed air conditioning mode Mb to the vehicle speed air conditioning mode Ma. Since the vehicle speed air conditioning mode Ma is applied, the voltage U of the blower 20 is turned OFF (the blower motor 22 does not start and the impeller 21 does not rotate). That is, heat exchange between the air W in the air duct 10 and the heat exchanger (evaporator 36 and heater core 42) is suppressed. As a result, the rate at which the temperature Th of the heater core 42 decreases slows down. Similarly, the rate at which the temperature Tv of the evaporator 36 increases slows down.

[0143] At time t6, the temperature Th of the heater core 42 becomes lower than the no-vehicle-speed lower limit temperature Tha (<Thb, for example, 45°C) defined by the automatic restart condition Ya in the no-vehicle-speed air conditioning mode Ma. Therefore, the engine 2 is automatically restarted and rotated. Since the engine 2 rotates, the temperature Th of the heater core 42 begins to rise. The electric compressor 31 rotates again. Since the electric compressor 31 rotates, the temperature Tv of the evaporator 36 begins to drop. The voltage U of the blower 20 switches to ON.

[0144] The scene changes. At time t7, the speed V of the vehicle 1 is equal to or higher than the first predetermined speed V1. The engine 2 is rotating. At time t8, the engine 2 automatically stops and the rotational speed Ne of the engine 2 becomes zero. At this time, the vehicle 1 travels by driving the motor 3. Thereby, the speed V of the vehicle 1 is maintained at or higher than the first predetermined speed V1. At time t9, similar to time t3, the engine 2 is automatically restarted and rotated. Other conditions are the same as those at times t1 - t3.

[0145] (Function and effect) Even if the blower air volume Qa of the air W by the blower 20 is reduced when the engine 2 automatically stops during the stop (no vehicle speed) of the vehicle 1, the vibration and road noise of the vehicle 1 are also reduced at the same time. Therefore, it does not give much discomfort to the passengers in the passenger compartment 8.

[0146] Therefore, in the no-vehicle-speed air conditioning mode Ma, the blower air volume Qa of the blower 20 is reduced compared to the blower air volume Q0 of the blower 20 immediately before the automatic stop of the engine 2.

[0147] On the other hand, when the engine 2 automatically stops during the running (with vehicle speed) of the vehicle 1, if the blower air volume Qb of the air W by the blower 20 is reduced, although there is no change in the vibration and road noise of the vehicle 1, only the blower air volume Qb of the blower 20 is reduced. Therefore, it may give a great sense of discomfort to the passengers in the passenger compartment 8.

[0148] Therefore, in the vehicle-speed air-conditioning mode Mb, the reduction amount (Q0 - Qb) of the air volume Qb blown by the blower 20 is made smaller than the reduction amount (Q0 - Qa) of the air volume Qa blown by the blower 20 in the non-vehicle-speed air-conditioning mode Ma (Q0 - Qb < Q0 - Qa). In other words, in the vehicle-speed air-conditioning mode Mb, the air volume Qb blown by the blower 20 is not reduced as much as possible from the air volume Q0 of the blower 20 immediately before the automatic stop of the engine 2.

[0149] Thereby, it is possible to make it difficult for the passengers in the passenger compartment 8 to notice the change in air conditioning when the engine 2 automatically stops during the running of the vehicle 1.

[0150] Particularly in this embodiment, in the vehicle-speed air-conditioning mode Mb, the air volume Qb of the air W blown by the blower 20 is not reduced (Qb = Q0). Thereby, when the engine 2 automatically stops during the running of the vehicle 1, almost no discomfort is given to the passengers in the passenger compartment 8.

[0151] In the vehicle-speed air-conditioning mode Mb, since the air volume Qb of the blower 20 is hardly reduced, if the vehicle-speed air-conditioning mode Mb is maintained for a long time, the heat exchange between the air W in the air duct 10 and the heat exchangers (the evaporator 36 and the heater core 42) is promoted, and there is a possibility that the cooling and heating capacity of the air conditioner 9 may decrease.

[0152] On the other hand, in the non-vehicle-speed air-conditioning mode Ma, since the air volume Qa of the blower 20 is reduced, the heat exchange between the air W in the air duct 10 and the heat exchangers (the evaporator 36 and the heater core 42) is suppressed, and it becomes difficult for the cooling and heating capacity of the air conditioner 9 to decrease.

[0153] Therefore, when the speed V of the vehicle 1 reaches the second predetermined speed V2 (0 km / h) which is smaller than the first predetermined speed V1 (5 km / h) during the progress of the vehicle-speed air-conditioning mode Mb, by switching the air-conditioning mode from the vehicle-speed air-conditioning mode Mb to the non-vehicle-speed air-conditioning mode Ma, it is possible to suppress the decrease in the cooling and heating capacity of the air conditioner 9.

[0154] In the vehicle-speed air conditioning mode Mb, the automatic restart condition Yb is set to be stricter than the automatic restart condition Ya in the non-vehicle-speed air conditioning mode Ma, making it easier to automatically restart the engine 2. This suppresses the decrease in the cooling and heating capacity of the air conditioner 9 caused by the automatic shutdown of the engine 2.

[0155] The temperature conditions of the heat exchanger (evaporator 36 and heater core 42) and the comfort conditions of the passenger compartment 8 (temperature conditions of the passenger compartment 8) can be suitably set as the automatic restart conditions Ya and Yb for the engine 2.

[0156] The evaporator 36 and heater core 42 enable efficient heat exchange with the air W in the air duct 10.

[0157] In hybrid mode and with vehicle-speed air conditioning mode Mb, vehicle 1 is driven by motor 3, or vehicle 1 is decelerating and motor 3 is generating regenerative power, so even when engine 2 is automatically stopped, vehicle 1 can be driven efficiently.

[0158] By using different heat exchange circuits (hot water circulation circuit 50 vs engine coolant circulation circuit 40) for the electric mode and the hybrid mode, optimal air conditioning control can be performed according to each operating mode.

[0159] (Other embodiments) Although this disclosure has been described above with reference to preferred embodiments, this description is not limiting, and various modifications are, of course, possible.

[0160] In the vehicle speed air conditioning mode Mb, the airflow rate Qb of the air W supplied by the blower 20 may be slightly reduced. The automatic restart conditions Ya, Yb may include only one of the following: the temperature condition of the evaporator 36, the temperature condition of the heater core 42, and the comfort condition of the passenger compartment 8. The same applies to the automatic stop conditions Xa, Xb. The comfort condition of the passenger compartment 8 may include the humidity condition of the passenger compartment 8. The refrigerant circulation circuit 30 may include a mechanical compressor linked to the engine 2 instead of the electric compressor 31. The air conditioning control system S may be applied to both cases: when cooling the passenger compartment 8 (cooling scene) and when heating the passenger compartment 8 (heating scene). Vehicle 1 may be a mild hybrid (MHEV) vehicle. Vehicle 1 may be a simple engine vehicle. [Industrial applicability]

[0161] This disclosure is extremely useful and has high industrial applicability because it can be applied to vehicle air conditioning control systems. [Explanation of symbols]

[0162] S Air Conditioning Control System W Air Ma (Automatic Vehicle Speed ​​Air Conditioning Mode) Mb with vehicle speed air conditioning mode V speed V1 1st predetermined speed V2 2nd predetermined speed Q0 Air flow rate Qa Airflow Qb Air flow rate Xa automatic stop condition Xb automatic stop condition Ha Automatic Restart Conditions Yb Automatic restart conditions 1 vehicle 2 engines 3 motors 8 Cabin 9. Air conditioner 10 Air duct 20 Blower 30 Refrigerant circulation circuit (heat exchange circuit) 31 Electric Compressor 36 Evaporator (heat exchanger) 40. Engine coolant circulation circuit (heat exchange circuit) 41 Water pump 42 Heater core (heat exchanger) 50 Hot water circulation circuit (heat exchange circuit) 51 Electric pump 52 Heater 60 Controllers (control devices)

Claims

1. A vehicle air conditioning control system comprising an engine capable of automatically stopping based on automatic stop conditions, an air conditioner for harmonizing the air in the vehicle cabin, and a control device for controlling the air conditioner, The aforementioned air conditioner is An air duct through which air flows, A heat exchange circuit including a heat exchanger that performs heat exchange with the air in the air duct, The system includes a blower that supplies the air from the air duct to the vehicle compartment, The control device is capable of switching between a vehicle-speed-free air conditioning mode when the vehicle speed is below a first predetermined speed when the engine is automatically stopped, and a vehicle-speed-enabled air conditioning mode when the vehicle speed is at or above the first predetermined speed when the engine is automatically stopped. In the vehicle-speed-free air conditioning mode, the control device reduces the airflow rate of the blower to a level lower than the airflow rate of the blower immediately before the automatic stop. The control device, in the vehicle-speed air conditioning mode, reduces the amount of reduction in the airflow volume of the blower to a smaller amount than the amount of reduction in the vehicle-speed air conditioning mode. The control device is a vehicle air conditioning control system that, when the vehicle's speed reaches a second predetermined speed less than the first predetermined speed while the vehicle is in the vehicle speed air conditioning mode, switches the air conditioning mode from the vehicle speed air conditioning mode to the vehicle non-vehicle speed air conditioning mode.

2. A vehicle air conditioning control system comprising an engine capable of automatically stopping based on automatic stop conditions, an air conditioner for harmonizing the air in the vehicle cabin, and a control device for controlling the air conditioner, The aforementioned air conditioner is An air duct through which air flows, A heat exchange circuit including a heat exchanger that performs heat exchange with the air in the air duct, The system includes a blower that supplies the air from the air duct to the vehicle compartment, The control device is capable of switching between a vehicle-speed-free air conditioning mode when the vehicle speed is below a first predetermined speed when the engine is automatically stopped, and a vehicle-speed-enabled air conditioning mode when the vehicle speed is at or above the first predetermined speed when the engine is automatically stopped. In the vehicle-speed-free air conditioning mode, the control device reduces the airflow rate of the blower to a level lower than the airflow rate of the blower immediately before the automatic stop. The control device, in the vehicle-speed air conditioning mode, reduces the amount of reduction in the airflow volume of the blower to a smaller amount than the amount of reduction in the vehicle-speed air conditioning mode. The engine is capable of automatic restart based on automatic restart conditions. The control device is a vehicle air conditioning control system that, in the vehicle-speed air conditioning mode, automatically restarts the engine based on automatic restart conditions that are stricter than the automatic restart conditions in the non-vehicle-speed air conditioning mode.

3. A vehicle air conditioning control system according to claim 1 or 2, The control device is a vehicle air conditioning control system that does not reduce the amount of air supplied in the vehicle speed air conditioning mode.

4. A vehicle air conditioning control system according to claim 2, The automatic restart condition includes at least one of the temperature condition of the heat exchanger and the comfort condition of the passenger compartment, in a vehicle air conditioning control system.

5. A vehicle air conditioning control system according to claim 1 or 2, The heat exchange circuit is an air conditioning control system for a vehicle, comprising at least one of an evaporator and a heater core as the heat exchanger.

6. A vehicle air conditioning control system according to claim 1 or 2, The aforementioned vehicle is equipped with a motor, The vehicle is switchable between an electric mode, which is driven solely by the motor, and a hybrid mode, which is driven by at least one of the motor and the engine. A vehicle air conditioning control system in which, in the hybrid mode and the vehicle speed air conditioning mode, the vehicle is driven by the motor, or the vehicle is decelerating and the motor is generating regenerative power.

7. A vehicle air conditioning control system according to claim 1 or 2, The aforementioned vehicle is equipped with a motor, The vehicle is switchable between an electric mode, which is driven solely by the motor, and a hybrid mode, which is driven by at least one of the motor and the engine. In the case of the electric mode, a different heat exchange circuit is used than the heat exchange circuit used in the hybrid mode. The vehicle's air conditioning control system, wherein the aforementioned non-vehicle-speed air conditioning mode and the aforementioned vehicle-speed air conditioning mode can only be set in the hybrid mode.

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