Vehicle air conditioning device

Abstract

The vehicle air conditioner includes: a cooling heat exchanger (26) for cooling the supply air, a temperature detection unit (31) for detecting the cooling temperature of the supply air, a compressor (22) for compressing and discharging the refrigerant that has passed through the cooling heat exchanger (26), a target temperature setting unit (40a) for setting the target cooling temperature of the supply air, a compressor control unit (40b) for controlling the operation of the compressor, and a driving state determination unit (40c) for determining the driving state of the vehicle. The target temperature setting unit sets a corrected target temperature (TEOK) higher than the normal target temperature as the target cooling temperature when the driving state determination unit determines that the vehicle starts to decelerate. The compressor control unit stops the operation of the compressor when the vehicle starts to decelerate, and when the cooling temperature of the supply air becomes equal to or higher than the corrected target temperature, the compressor control unit starts the operation of the compressor.

Description

[0001] Cross-reference to Related Applications

[0002] This application is based on Japanese Patent Application No. 2020-74539 filed on April 20, 2020, the contents of which are incorporated herein by reference. Technical Field

[0003] The present invention relates to an air conditioner for a vehicle. Background Art

[0004] Patent Document 1 proposes an air conditioner for a vehicle that stores cold in an evaporator during deceleration and sets a correction temperature, which is a specified value higher than a reference temperature, as the target cooling temperature of the evaporator at the end of deceleration. In this vehicle air conditioner, it is possible to extend the stop time of the compressor during parking within a range that does not affect the cooling feeling.

[0005] Prior Art Documents

[0006] Patent Documents

[0007] Patent Document 1: Japanese Unexamined Patent Application Publication No. 2005-104306

[0008] However, as in the vehicle air conditioner of Patent Document 1 above, when using the heat and cold accumulated in the evaporator during driving after parking, since the parking time varies depending on conditions such as the road environment, for example, in the case of a short parking time, the heat and cold accumulated in the evaporator may not be used up. In such a case, the stop time of the compressor becomes short, and the effect of fuel consumption reduction becomes low. Summary of the Invention

[0009] In view of the above points, an object of the present invention is to improve the effect of fuel consumption reduction in a vehicle air conditioner that cools the interior of the vehicle with the compressor stopped during parking.

[0010] To achieve the above object, in a first aspect of the present invention, there are provided: a cooling heat exchanger, a temperature detection unit, a compressor, a target temperature setting unit, a compressor control unit, and a driving state determination unit.

[0011] The cooling heat exchanger exchanges heat between the supply air blown into the vehicle interior and a refrigerant to cool the supply air. The temperature detection unit detects the cooling temperature of the supply air based on the cooling heat exchanger. The compressor is driven by the vehicle engine, compresses and discharges the refrigerant that has passed through the cooling heat exchanger. The target temperature setting unit sets the target cooling temperature of the supply air based on the cooling heat exchanger. The compressor control unit controls the operation of the compressor based on the cooling temperature and the target cooling temperature. The driving state determination unit determines the driving state of the vehicle.

[0012] When the driving state determination unit determines that the vehicle is traveling normally, the target temperature setting unit sets the normal target temperature as the control target temperature. When the driving state determination unit determines that the vehicle starts to decelerate, the target temperature setting unit sets a corrected target temperature higher than the normal target temperature as the control target temperature.

[0013] When the driving state determination unit determines that the vehicle starts to decelerate, the compressor control unit stops the compressor, and when the cooling temperature detected by the temperature detection unit becomes equal to or higher than the corrected target temperature, the compressor control unit starts the compressor.

[0014] In addition, in the second aspect of the present invention, when the driving state determination unit determines that the vehicle starts to decelerate, the compressor control unit stops the compressor, and when a predetermined time has elapsed since the compressor stopped operating, the compressor control unit starts the compressor.

[0015] Thus, in addition to during parking, indoor cooling can be performed using the cold and heat accumulated in the evaporator even when the vehicle is decelerating. As a result, even when the parking time is short, the cold and heat accumulated in the evaporator can be effectively utilized to extend the compressor stop time as much as possible, and the fuel consumption saving effect can be improved. Description of the Drawings [[ID=X]] [[ID=X]]

[0016] [[ID=X]] Figure 1 is a diagram showing the vehicle air conditioner according to the first embodiment. [[ID=X]] [[ID=X]]

[0017] [[ID=X]] Figure 2 is a front view showing the evaporator. [[ID=X]] [[ID=X]]

[0018] [[ID=X]] Figure 3 is a flowchart showing the compressor control process executed by the vehicle air conditioner according to the first embodiment. [[ID=X]] [[ID=X]]

[0019] [[ID=X]] Figure 4 is a timing diagram showing the operation of the vehicle air conditioner according to the first embodiment. [[ID=X]] [[ID=X]]

[0020] [[ID=X]] Figure 5 is a flowchart showing the compressor control process executed by the vehicle air conditioner according to the second embodiment. [[ID=X]] Detailed Description of the Invention [[ID=X]] [[ID=X]]

[0021] Hereinafter, with reference to the accompanying drawings, a plurality of modes for implementing the present invention will be described. In each mode, parts corresponding to those described in the previous mode may be denoted by the same reference numerals and redundant descriptions may be omitted. When only a part of the structure is described in each mode, other previously described modes can be applied to other parts of the structure. In each embodiment, unless specifically indicated that combinations of parts that can be combined are combined with each other, parts of the embodiments can be combined with each other partially even if not specifically indicated as long as there is no particular obstacle to the combination.

[0022] (First Embodiment)

[0023] Hereinafter, based on the accompanying drawings, the first embodiment of the present invention will be described.

[0024] Figure 1 The vehicle air conditioner 1 shown is mounted on a vehicle equipped with, for example, an engine 10 as a driving internal combustion engine, and conditions the air in the vehicle interior. The vehicle of the present embodiment performs an engine stop control for stopping the engine 10 during a temporary stop of the vehicle. The engine stop control is a control for achieving fuel consumption reduction by stopping the engine 10 when the vehicle is stopped.

[0025] The engine 10 is an internal combustion engine mounted on a vehicle. The vehicle equipped with the vehicle air conditioner 1 may be, for example, a hybrid vehicle that further includes a driving electric motor in addition to the engine 10.

[0026] The vehicle air conditioner 1 includes a refrigeration cycle device 20. The refrigeration cycle device 20 is provided in a refrigerant flow path 21 through which a refrigerant circulates. In the present embodiment, an HFO-based refrigerant (specifically, R1234yf) is used as the refrigerant. The refrigeration cycle device 20 is a vapor compression type subcritical refrigeration cycle in which the refrigerant pressure on the high-pressure side does not exceed the critical pressure of the refrigerant.

[0027] A compressor 22, a condenser 23, a liquid receiver 24, an expansion valve 25, and an evaporator 26 are provided in the refrigerant flow path 21. The constituent devices 22 to 26 of these refrigeration cycle devices 20 are respectively connected through the refrigerant flow path 21 to form a closed loop.

[0028] The compressor 22 sucks in the refrigerant and compresses it until it becomes a high-pressure refrigerant and discharges it. The compressor 22 of the present embodiment is an engine-driven compressor that is driven by a rotational driving force transmitted from the vehicle driving engine 10 via a belt pulley, a belt, etc. The operation of the compressor 22 is controlled by an air conditioner control device 40. The air conditioner control device 40 will be described later.

[0029] The compressor 22 can be either a variable capacity type compressor or a fixed capacity type compressor. The variable capacity type compressor is a compressor capable of adjusting the refrigerant discharge capacity by changing the discharge capacity. The fixed capacity type compressor is a compressor capable of adjusting the refrigerant discharge capacity by changing the operation rate of the compressor through the disconnection of the electromagnetic clutch.

[0030] The compressor 22 is disposed, for example, in the engine room of the vehicle and is driven by the driving force of the engine 10. When the idling stop control is performed, the compressor 22 stops, and thus the refrigeration cycle device 20 stops. That is, the idling stop control can also be referred to as the compressor stop control.

[0031] In the present embodiment, the vehicle air conditioner 1 can be operated even during the idling stop control. During the idling stop control, air-conditioned air is blown into the vehicle interior in a state where the compressor 22 is stopped.

[0032] The refrigerant inlet side of the condenser 23 is connected to the discharge side of the compressor 22. The condenser 23 is a heat exchanger that exchanges heat between the high-pressure gaseous refrigerant discharged from the compressor 22 and the outside air blown by a cooling fan (not shown). The condenser 23 dissipates heat from the high-pressure gaseous refrigerant to condense it.

[0033] The accumulator 24 is connected to the outlet side of the condenser 23. The accumulator 24 stores the remaining liquid-phase refrigerant in the refrigeration cycle device 20 inside.

[0034] The expansion valve 25 is connected to the outlet side of the accumulator 24. The expansion valve 25 is a refrigerant flow rate adjustment mechanism that reduces the pressure of the refrigerant flowing out from the accumulator 24 and adjusts the refrigerant flow rate of the refrigerant circulating in the cycle.

[0035] The expansion valve 25 of the present embodiment is a thermal expansion valve that changes the throttle opening degree in such a way that the superheat degree of the refrigerant on the outlet side of the evaporator 26 approaches a preset reference superheat degree. The thermal expansion valve is a mechanical variable throttle mechanism having a temperature sensing portion and a valve core portion. The temperature sensing portion has a deformable member (specifically, a diaphragm) that deforms according to the temperature and pressure of the refrigerant on the outlet side of the evaporator 26, and the valve core portion is displaced according to the deformation of the deformable member, thereby changing the throttle opening degree.

[0036] The evaporator 26 is connected to the outlet of the expansion valve 25. The evaporator 26 is a cooling heat exchanger that cools the air blown into the vehicle interior. The evaporator 26 exchanges heat between the air blown into the vehicle interior and the low-pressure refrigerant flowing out from the expansion valve 25. The evaporator 26 evaporates the low-pressure refrigerant to exert an endothermic effect to cool the blown air.

[0037] Here, Figure 2 the evaporator 26 will be described. AsFigure 2 As shown, the evaporator 26 of the present embodiment has a pair of header tanks 26a, 26b and a plurality of tubes 26c connecting between these header tanks 26a, 26b. The pair of header tanks 26a, 26b are arranged in parallel with a specified distance separating them from each other. The plurality of tubes 26c are arranged at equal intervals between these header tanks 26a, 26b. Each tube 26c communicates with the corresponding header tank 26a, 26b at its end.

[0038] The tube 26c is formed in a flat shape and is a porous tube having a plurality of refrigerant passages inside. This tube 26c can be obtained by, for example, an extrusion manufacturing method. The plurality of refrigerant passages extend along the long side direction of the tube 26c and open at both ends of the tube 26c.

[0039] A plurality of gaps are formed between the plurality of tubes 26c. A plurality of fins 26d and a plurality of cold storage material containers 26e are provided in these plurality of gaps. The plurality of fins 26d and the plurality of cold storage material containers 26e are arranged, for example, according to a specified regularity.

[0040] The evaporator 26 is provided with fins 26d for increasing the contact area with the air supplied to the vehicle interior. The fins 26d are arranged in the air passages partitioned between two adjacent tubes 26c. The fins 26d are thermally bonded to two adjacent tubes 26c. The fins 26d are brazed to two adjacent tubes 26c. The fins 26d are formed by bending a thin metal plate such as aluminum into a corrugated shape.

[0041] The cold storage material container 26e is arranged between two adjacent tubes 26c. The cold storage material container 26e is made of a metal such as aluminum. The cold storage material container 26e is thermally bonded to the two tubes 26c arranged on both sides of it. The cold storage material container 26e of the present embodiment is brazed to the tube 26c.

[0042] A cold storage material capable of storing heat and cold is accommodated in the cold storage material container 26e. As the cold storage material, for example, paraffin having a freezing point of about 10°C can be used. The evaporator 26 is a cold storage heat exchanger that can solidify the cold storage material to store heat and cold when the refrigerant evaporates to exert a heat absorption effect.

[0043] In the evaporator 26, heat storage in the cold storage material is performed during the operation of the compressor 22. In the evaporator 26, when the engine 10 stops and the compressor 22 stops operating, cold is released from the cold storage material. Thus, even if the compressor 22 temporarily stops, the cold heat stored in the evaporator 26 can be used to cool the air supplied to the vehicle interior for interior refrigeration.

[0044] When the blowing temperature of the evaporator 26 is higher than a specified temperature, or when the restart condition of the engine 10 is satisfied, the engine 10 restarts and thus the compressor 22 starts operating. By the cold storage function of the evaporator 26, it is possible to extend the time required for the blowing temperature of the evaporator 26 to rise. Thereby, it is possible to extend the stop time of the compressor 22, and it is possible to improve the power saving effect of the compressor 22. In addition, as the stop time of the compressor 22 is extended, it is possible to extend the stop time of the engine 10, and thus it is possible to improve the fuel consumption saving effect of the engine 10.

[0045] Return Figure 1 , the evaporator 26 is disposed inside the air-conditioning case 30. The air-conditioning case 30 constitutes an air passage of the vehicle air-conditioning apparatus 1.

[0046] In the air-conditioning case 30, an evaporator blowing temperature sensor 31 is provided at a position immediately behind the evaporator 26 on the downstream side of the air flow. The evaporator blowing temperature sensor 31 is a temperature detection unit that detects the temperature of the supply air immediately after passing through the evaporator 26, and detects the evaporator cooling temperature TE which is the cooling temperature of the supply air based on the evaporator 26. The evaporator cooling temperature TE can also be referred to as the temperature of the evaporator 26. The sensor signal of the evaporator blowing temperature sensor 31 is input to the air-conditioning control device 40.

[0047] A blower 32 is provided in the air-conditioning case 30. The blower 32 constitutes a blowing unit that generates an air flow inside the air-conditioning case 30. The blower 32 blows the air inside the vehicle (inside air) or the air outside the vehicle (outside air) sucked from an outside-air / inside-air switching box (not shown) toward the passenger compartment. The operation of the blower 32 is controlled by the air-conditioning control device 40.

[0048] After the supply air passes through the evaporator 26, it passes through a heater unit (not shown) and is blown out from a blow-out port (not shown) toward the passenger compartment. The blow-out ports include: a face blow-out port that blows air toward the upper body of the occupant, a foot blow-out port that blows air toward the feet of the occupants inside the vehicle, and a defrost blow-out port that blows air toward the inner surface of the windshield. By switching the blow-out port through which the supply air is blown out, it is possible to switch the blow-out modes such as the face mode, the foot mode, and the defrost mode.

[0049] The vehicle air-conditioning apparatus 1 includes an air-conditioning control device 40. The air-conditioning control device 40 is composed of a well-known microcomputer including a CPU, a ROM, a RAM, and the like and its peripheral circuits. The air-conditioning control device 40 performs various operations and processes based on a control program stored in the ROM, and thereby controls the operation of various controlled devices connected to the output side.

[0050] In addition to the sensor signal from the evaporator outlet temperature sensor 31, the air conditioner control device 40 is also input with the sensor signal from the sensor group 41. The sensor group 41 includes an interior air temperature sensor, an exterior air temperature sensor, a sunlight sensor, etc. The interior air temperature sensor detects the temperature inside the vehicle compartment. The exterior air temperature sensor detects the temperature outside the vehicle. The sunlight sensor checks the amount of sunlight irradiating into the vehicle compartment.

[0051] The switch signal from an operation panel (not shown) is input to the air conditioner control device 40. The operation switches of the operation panel include a temperature setting switch, a blower volume switching switch, a blowing mode switching switch, an interior / exterior air switching switch, an air conditioner switch for giving an operation instruction to the compressor 22, etc.

[0052] The air conditioner control device 40 controls the operation of the compressor 22 based on the evaporator cooling temperature TE and the target cooling temperature. The air conditioner control device 40 sets the normal target temperature TEO as the target cooling temperature of the supply air during normal driving of the vehicle, and controls the operation of the compressor 22 in such a way that the evaporator cooling temperature TE approaches the normal target temperature TEO. Normal driving can be regarded as, for example, a driving state where the vehicle speed is greater than 0 km / h and the vehicle is not in a decelerating driving state.

[0053] The normal target temperature TEO is determined based on the target blowing temperature TAO of the air blown into the vehicle compartment and with reference to the control map stored in advance in the air conditioner control device 40. The target blowing temperature TAO is calculated and determined using the detection signals of various control sensors and the operation signals of the operation panel.

[0054] Taking the start of vehicle deceleration as an opportunity, the air conditioner control device 40 changes the target cooling temperature of the supply air to the corrected target temperature TEOK, and controls the compressor 22 based on the evaporator cooling temperature TE and the corrected target temperature TEOK.

[0055] Even when the vehicle stops after deceleration, the target cooling temperature of the supply air is maintained as the corrected target temperature TEOK. That is, the control of the compressor 22 based on the corrected target temperature TEOK is carried out during vehicle deceleration and when the vehicle is stopped.

[0056] The corrected target temperature TEOK is set to be higher than the normal target temperature TEO, which is the reference value, by a specified temperature. The specified temperature is set to a value that can maintain the comfort of the occupants. In other words, it is a value that the occupants can tolerate the temperature change of the supply air blown into the vehicle compartment. In this embodiment, the corrected target temperature TEOK is set on the high-temperature side about 6°C higher than the normal target temperature TEO.

[0057] The compressor 22 stops operating taking the start of vehicle deceleration as an opportunity. And when the evaporator cooling temperature TE is greater than the corrected target temperature TEOK, the compressor 22 starts operating again.

[0058] The air conditioner control device 40 is connected to the brake control device 42 and the engine control device 43. The brake control device 42 and the engine control device 43 are composed of a well-known microcomputer including a CPU, a ROM, a RAM, etc. and its peripheral circuits. The brake control device 42 performs various controls related to the vehicle brake (not shown). The engine control device 43 performs various controls related to the engine 10.

[0059] A brake operation signal related to the operation state of a brake pedal (not shown) is input from the brake control device 42 to the air conditioner control device 40. In addition, a signal related to the operating state of the engine 10 and a throttle operation signal related to the operation state of a throttle pedal (not shown) are input from the engine control device 43 to the air conditioner control device 40.

[0060] The air conditioner control device 40 determines the driving state of the vehicle based on the signals received from the brake control device 42 and the engine control device 43. The driving state of the vehicle includes the operation state of the brake, the operation state of the throttle, the start of vehicle deceleration, acceleration from deceleration, stopping from deceleration, starting from a stop, and the operating state of the engine 10, etc.

[0061] The operation state of the brake includes: brake on as the case where a brake operation is detected, and brake off as the case where no brake operation is detected. Similarly, the operation state of the throttle includes: throttle on as the case where a throttle operation is detected, and throttle off as the case where no throttle operation is detected.

[0062] In the air conditioner control device 40, the structure for setting the target cooling temperature of the blown air is the target temperature setting unit 40a. In the air conditioner control device 40, the structure for controlling the operation of the compressor 22 is the compressor control unit 40b. In the air conditioner control device 40, the structure for determining the driving state of the vehicle is the driving state determination unit 40c.

[0063] The engine control device 43 performs fuel injection control to the engine 10 based on the operation amount of the throttle pedal. In the case where a prescribed fuel injection stop condition is satisfied, the engine control device 43 of the present embodiment performs fuel cut control for stopping the fuel injection to the engine 10. The fuel injection stop condition can be set to, for example, the case where the rotational speed of the engine 10 is equal to or higher than a prescribed rotational speed and throttle off is detected. Thus, fuel cut control is performed when the vehicle is decelerating.

[0064] Moreover, the engine control device 43 of the present embodiment performs idle stop control. In the idle stop control, when a specified engine stop condition is satisfied during the operation of the engine 10, the engine 10 is stopped, and when a specified engine restart condition is satisfied during the stop of the engine 10, the engine 10 is restarted. The engine stop condition can be set, for example, as a case where the vehicle speed is 0 km / h and the brake is detected to be on. The engine restart condition can be set, for example, as a case where the vehicle speed is greater than 0 km / h during the stop of the engine 10, or a case where the brake is detected to be off.

[0065] During the period of performing idle stop control starting from fuel cut-off control, the fuel injection to the engine 10 is maintained stopped. And, the fuel injection to the engine 10 is restarted with the restart of the engine 10.

[0066] Next, based on Figure 3 the flowchart shown below, the compressor control process executed by the air conditioner control device 40 will be described.

[0067] In S100, it is determined whether the air conditioner switch is on. In the determination process of S100, when it is determined that the air conditioner switch is not on, the compressor control process is ended. On the other hand, in the determination process of S100, when it is determined that the air conditioner switch is on, in S101, it is determined whether the vehicle starts to decelerate. In S101, for example, when the vehicle speed is greater than 0 km / h and the throttle is detected to be cut off or the brake is detected to be on, it can be determined that the vehicle starts to decelerate.

[0068] In the determination process of S101, when it is determined that the vehicle does not start to decelerate, in S102, the normal target temperature TEO is set as the target cooling temperature of the supply air, and in S103, the compressor 22 is started to operate. The air conditioner control device 40 controls the compressor 22 such that the evaporator cooling temperature TE approaches the normal target temperature TEO.

[0069] On the other hand, in the determination process of S101, when it is determined that the vehicle starts to decelerate, in S104, the corrected target temperature TEOK is set as the target cooling temperature of the supply air.

[0070] Next, in S105, it is determined whether the evaporator cooling temperature TE is equal to or higher than the corrected target temperature TEOK. In the determination process of S105, when it is determined that the evaporator cooling temperature TE is equal to or higher than the corrected target temperature TEOK, the processes of S102 and S103 are executed. [[ID= twenty - one]] [[ID= twenty - two]]

[0071] On the other hand, in the determination process of S105, when it is determined that the evaporator cooling temperature TE is not equal to or higher than the corrected target temperature TEOK, that is, when the evaporator cooling temperature TE is lower than the corrected target temperature TEOK, the compressor 22 is stopped in S106. During the stop of the compressor 22, the cold heat accumulated in the evaporator 26 is used to cool the air sent into the vehicle interior.

[0072] Next, in S107, it is determined whether the vehicle is decelerating. In the determination process of S107, when it is determined that the vehicle is decelerating, the process returns to S105. After transferring to S105, when it is determined that the evaporator cooling temperature TE is equal to or higher than the corrected target temperature TEOK during deceleration, the processes of S102 and S103 are executed.

[0073] On the other hand, in the determination process of S107, when it is determined that the vehicle is not decelerating, in S108, it is determined whether the vehicle has accelerated during deceleration, or whether it has started moving after stopping during deceleration. In S108, for example, when the vehicle speed is greater than 0 km / h and the throttle is on, it can be determined that acceleration has occurred. In addition, in S108, for example, when the vehicle speed is greater than 0 km / h during a stop, it can be determined that the vehicle has started moving. In a vehicle that performs idle stop control as in the present embodiment, even when the engine 10 is started for starting preparation, it can be determined in S108 that the vehicle has started moving. That is, the situation where the vehicle has started moving from a stop includes the situation where the vehicle speed is greater than 0 km / h and the situation where the engine 10 has been started for starting preparation although the vehicle speed is 0 km / h.

[0074] In the determination process of S108, when it is determined that the vehicle has not accelerated or started moving, that is, when the vehicle is in a stopped state, the process returns to S105. Thus, even when the vehicle stops after deceleration, the target cooling temperature is maintained at the corrected target temperature TEOK. After transferring to S105, when the evaporator cooling temperature TE is greater than the corrected target temperature TEOK during a stop, the processes of S102 and S103 are executed. On the other hand, in the determination process of S108, when it is determined that the vehicle has accelerated or started moving, the processes of S102 and S103 are executed.

[0075] Next, Figure 4 the operation of the vehicle air conditioner according to the present embodiment will be described using Figure 4 a timing chart. In

[0076] As Figure 4As shown, during normal driving of the vehicle, the target cooling temperature of the supply air is set to the normal target temperature TEO. The operation of the compressor 22 is controlled such that the evaporator cooling temperature TE approaches the normal target temperature TEO.

[0077] In the present embodiment, upon the start of deceleration, the target cooling temperature is changed to the corrected target temperature TEOK, and the compressor 22 is stopped. In the present embodiment, during the stop after deceleration, the target cooling temperature is also maintained at the corrected target temperature TEOK. Fuel injection to the engine 10 is stopped at the start of deceleration, and further, the engine 10 is stopped during the stop.

[0078] Moreover, when the evaporator cooling temperature TE is greater than the corrected target temperature TEOK during the stop, or when the engine 10 is started during the stop, the target cooling temperature is changed to the normal target temperature TEO, and the compressor 22 is started. When the evaporator cooling temperature TE is greater than the corrected target temperature TEOK during the stop, the engine 10 and the compressor 22 are started together, and thus fuel injection to the engine 10 is restarted.

[0079] Figure 4 The example shown represents the case where the evaporator cooling temperature TE becomes greater than the corrected target temperature TEOK during the stop. The evaporator cooling temperature TE that has risen to the corrected target temperature TEOK decreases toward the normal target temperature TEO.

[0080] In the comparative example, during deceleration of the vehicle, the target cooling temperature is maintained at the normal target temperature TEO. And, at the start of the stop, the target cooling temperature is changed to the corrected target temperature TEOK, and the compressor 22 is stopped.

[0081] In the comparative example, the vehicle starts moving before the evaporator cooling temperature TE reaches the corrected target temperature TEOK during the stop. Therefore, the compressor 22 is started before the evaporator cooling temperature TE reaches the corrected target temperature TEOK. That is, in the comparative example, the cold heat accumulated in the evaporator 26 cannot be exhausted, and thus the effect of saving fuel consumption is reduced.

[0082] In the embodiment described above, on the occasion of the start of vehicle deceleration, the target cooling temperature is changed to the corrected target temperature TEOK on the high-temperature side, and the compressor 22 is stopped. As a result, in addition to during parking, indoor cooling can be performed using the cold heat accumulated in the evaporator 26 even during vehicle deceleration. As a result, even when the parking time is short, the cold heat accumulated in the evaporator 26 can be effectively utilized. Therefore, as long as it is a vehicle that performs fuel cut control and idle stop control, the stop time of fuel injection to the engine 10 can be extended as much as possible, and the effect of fuel consumption savings can be improved. Moreover, since the stop time of the compressor 22 can be extended as much as possible, the effect of fuel consumption savings can also be improved.

[0083] In addition, in the present embodiment, the evaporator 26 having a cold storage material is used. As a result, the cold storage amount of the evaporator 26 can be increased. Therefore, the time until the evaporator cooling temperature TE reaches the corrected target temperature TEOK can be extended, and thus the stop time of the compressor 22 can be effectively extended.

[0084] (Second Embodiment)

[0085] Next, a second embodiment of the present invention will be described. Hereinafter, only the parts different from the above-described first embodiment will be described.

[0086] In the present second embodiment, the compressor 22 is stopped from the start of vehicle deceleration, and the compressor 22 is started at the moment after a predetermined time has elapsed since the start of deceleration. The predetermined time is a time during which the comfort of the occupants can be maintained after the compressor 22 stops, and is set to the compressor stoppable time T1 of the temperature change of the supply air blown into the vehicle interior after the compressor 22 stops that the occupants can tolerate. The compressor stoppable time T1 can be set to, for example, the time required for the evaporator cooling temperature TE to reach a predetermined temperature (for example, the corrected target temperature TEOK in the above-described first embodiment) higher than the normal target temperature TEO.

[0087] The compressor stoppable time T1 varies according to the cold storage amount of the evaporator 26. For example, the larger the cold storage amount of the evaporator 26, the longer the compressor stoppable time T1, and the smaller the cold storage amount of the evaporator 26, the shorter the compressor stoppable time T1.

[0088] The cold storage amount of the evaporator 26 is related to the operating time of the compressor 22, and the operating time of the compressor 22 is related to the driving state of the vehicle. As information related to the driving state of the vehicle, for example, the driving time of the vehicle (that is, the operating time of the engine 10), the engine speed of the engine 10, etc. can be cited.

[0089] In addition, the stoppable time T1 of the compressor varies according to the outside air temperature. For example, the lower the outside air temperature, the longer the stoppable time T1 of the compressor, and the higher the outside air temperature, the shorter the stoppable time T1 of the compressor.

[0090] Therefore, the stoppable time T1 of the compressor can be calculated based on at least any one of the driving time of the vehicle, the rotational speed of the engine 10, and the outside air temperature. The stoppable time T1 of the compressor can be calculated based on any one of the driving time of the vehicle, the rotational speed of the engine 10, and the outside air temperature, or the stoppable time T1 of the compressor can be calculated by arbitrarily combining the driving time of the vehicle, the rotational speed of the engine 10, and the outside air temperature.

[0091] Next, based on Figure 5 the flowchart, the compressor control process executed by the air conditioner control device 40 of the second embodiment will be described. Figure 5 The processes of S100 to S103 and S106 to S108 in Figure 3 are the same as the processes of the above-described first embodiment described using

[0092] As Figure 5 shown, in the second embodiment, in the determination process of S101, when it is determined that the vehicle starts to decelerate, the stoppable time T1 of the compressor is set in S109, and the timer T is started in S110. In the process of S109, the stoppable time T1 of the compressor can be set based on, for example, information related to the driving state of the vehicle. The timer T is used to measure the elapsed time since the compressor 22 stopped operating. The elapsed time since the compressor 22 stopped operating is also the elapsed time since the vehicle started to decelerate.

[0093] Next, in S111, it is determined whether the timer T has reached or exceeded the stoppable time T1 of the compressor. In the determination process of S111, when it is determined that the timer T has reached or exceeded the stoppable time T1 of the compressor, the processes of S102 and S103 are executed. On the other hand, in the determination process of S111, when it is determined that the timer T has not reached or exceeded the stoppable time T1 of the compressor, the processes of S106 to S108 are executed.

[0094] In the second embodiment described above, the operation of the compressor 22 is stopped on the occasion of the start of deceleration of the vehicle, and the operation of the compressor 22 is started at the moment when the compressor stoppable time T1 has elapsed since the start of deceleration. Thus, in addition to during parking, indoor cooling can be performed using the cold heat accumulated in the evaporator 26 also during vehicle deceleration. As a result, even when the stop time of the vehicle is short, the cold heat accumulated in the evaporator 26 can be effectively utilized to extend the stop time of the compressor 22 as much as possible, and the effect of fuel consumption savings can be improved.

[0095] In addition, in the second embodiment, the operation of the compressor 22 is started at the moment when the measurement time measured by the timer T reaches the compressor stoppable time T1. Therefore, when restarting the operation of the compressor 22 that has been stopped on the occasion of the start of deceleration of the vehicle, it is not necessary to measure the evaporator cooling temperature TE by the evaporator outlet temperature sensor 31.

[0096] The present invention is not limited to the above-described embodiments, and various modifications can be made as follows within the scope not departing from the gist of the present invention. In addition, the means disclosed in the above-described embodiments can be appropriately combined within the range where they can be implemented.

[0097] For example, in the above-described embodiments, an example in which the evaporator 26 provided with the cold storage material is used has been described, but the present invention can also be applied to the case where an evaporator not provided with the cold storage material is used.

[0098] In addition, in the above-described embodiments, the operation of the compressor 22 is stopped simultaneously with the start of deceleration of the vehicle, but it is not necessarily the case that the operation of the compressor 22 is stopped simultaneously with the start of deceleration of the vehicle. Specifically, the operation of the compressor 22 can be stopped at any moment from the start of deceleration of the vehicle to the stop of the vehicle.

[0099] In addition, in the above-described embodiments, an example in which the vehicle air conditioner device of the present invention is applied to a vehicle performing idle stop control has been described, but the vehicle air conditioner device of the present invention can also be applied to a vehicle not performing idle stop control.

[0100] In addition, in the above-described embodiments, an example in which the vehicle air conditioner device of the present invention is applied to a vehicle performing fuel cut-off control has been described, but the vehicle air conditioner device of the present invention can also be applied to a vehicle not performing fuel cut-off control.

[0101] In addition, in the above-described embodiments, the start of deceleration is determined based on the vehicle speed and the throttle operation or the brake operation, but it is not limited thereto, and the start of deceleration of the vehicle can also be determined by different conditions.

[0102] The present invention has been described based on the embodiments, but it should be understood that the present invention is not limited to these embodiments and structures. The present invention also includes various modifications and variations within the equivalent scope. In addition, the present invention shows various combinations and modes, but combinations and modes that include only one element, more than one element, or less than one element are also included in the scope and spirit of the present invention.

Claims

1. An air conditioning device for a vehicle, characterized in that, Comprising: A cooling heat exchanger that exchanges heat between the supply air blown into the vehicle interior and a refrigerant to cool the supply air; A temperature detection unit that detects the cooling temperature of the supply air based on the cooling heat exchanger; A compressor driven by the vehicle engine that compresses and discharges the refrigerant that has passed through the cooling heat exchanger; A target temperature setting unit that sets a target cooling temperature of the supply air based on the cooling heat exchanger; A compressor control unit that controls the operation of the compressor based on the cooling temperature and the target cooling temperature; And A driving state determination unit that determines the driving state of the vehicle. When the driving state determination unit determines that the vehicle is in normal driving, the target temperature setting unit sets the normal target temperature as the target cooling temperature, and when the driving state determination unit determines that the vehicle starts to decelerate, the target temperature setting unit sets a corrected target temperature higher than the normal target temperature as the target cooling temperature. The compressor control unit stops the operation of the compressor when the driving state determination unit determines that the vehicle starts to decelerate, and during deceleration driving, the compressor control unit controls the cooling temperature so as to maintain the cooling temperature detected by the temperature detection unit as the corrected target temperature which is the target cooling temperature. During deceleration driving, when the cooling temperature becomes equal to or higher than the corrected target temperature, the compressor control unit starts the operation of the compressor.

2. The vehicle air conditioner according to claim 1, wherein When a predetermined time has elapsed since the compressor stopped operating, the compressor control unit starts the operation of the compressor.

3. The vehicle air conditioner according to claim 2, wherein The compressor control unit sets the predetermined time based on at least any one of the driving time of the vehicle, the engine speed, and the outside air temperature.

4. The vehicle air conditioner according to any one of claims 1 to 3, wherein After stopping the operation of the compressor, when the driving state determination unit determines that the vehicle has accelerated during deceleration or has started moving during a stop after deceleration, the compressor control unit starts the operation of the compressor.

5. The vehicle air conditioner according to any one of claims 1 to 3, wherein When the speed of the vehicle is greater than 0 km / h and no throttle operation of the vehicle is detected, or when a brake operation of the vehicle is detected, the driving state determination unit determines that the vehicle starts to decelerate.

6. The vehicle air conditioner according to any one of claims 1 to 3, wherein The cooling heat exchanger includes a cold storage material capable of storing cold and heat.

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