Vehicle heat pump circuit device

Abstract

The configuration makes it possible to suppress compressor noise while ensuring the necessary heating capacity. A compressor (11) is configured to suck in, compress, and discharge refrigerant; a heating unit (13, 131) is configured to heat an object to be heated by using refrigerant discharged from the compressor (11) as a heat source; an expansion unit (14c) is configured to expand refrigerant flowing out of the heating unit (13, 131); and a heat absorption unit (20) is configured to cause refrigerant expanded by the expansion unit (14c) to absorb heat generated by a heat generation unit (70). The heat absorption unit (20) is configured to increase a heat absorption amount in accordance with a reduction in the allowable noise level of the compressor (11).

Description

Cross-reference to related applications

[0001] This application is based on Japanese Patent Application No. 2022-179484, filed on November 9, 2022. The entire disclosures of all the above applications are hereby incorporated by reference. Technical area

[0002] The present disclosure relates to a vehicle heat pump cycle device having a heating unit that heats an object to be heated by using a refrigerant discharged from a compressor and heat generated by a heat generating unit as heat sources. State of the art

[0003] Conventionally, Patent Literature 1 describes a vehicle heat pump cycle that provides a required heating capacity (specifically, space heating capacity) through a sum of the amount of compressor work and the amount of heat absorbed by a chiller. The chiller is a heat exchanger that exchanges heat between a low-pressure refrigerant in a heat pump cycle and a low-temperature side heat medium in a low-temperature side heat medium circuit, and absorbs heat from the low-temperature side heat medium. An electric heater is provided in the low-temperature side heat medium circuit as a heat generation unit for heating the low-temperature side heat medium. State of the art literaturePatent literature

[0004] Patent Literature 1:JP2022-128546A Summary of the invention

[0005] With this conventional technology, when the amount of heat absorbed by the chiller is small, it is necessary to increase the compressor speed to increase the compressor's working amount. Increasing the compressor speed will result in an increase in compressor noise. Compressor noise is easily suppressed when the vehicle speed is high and the driving noise is loud, or when the air conditioning interior fan has a large air volume and the operating noise and blowing noise of the interior fan are loud. However, when the vehicle speed is low or the air volume of the interior fan is small, the compressor noise becomes noticeable and it may not be possible to increase the compressor speed. Therefore, it may be difficult to ensure the required heating capacity.

[0006] In view of the above, it is an object of the present disclosure to achieve both suppression of compressor noise and ensuring a necessary heating capability.

[0007] According to a first aspect of the present disclosure, a heat pump cycle device includes a compressor, a heating unit, an expansion unit, and a heat absorption unit.

[0008] The compressor is configured to suck in, compress, and discharge a refrigerant. The heating unit is configured to heat an object to be heated by using a refrigerant discharged from the compressor as a heat source. The expansion unit is configured to expand a refrigerant flowing out of the heating unit. The heat absorption unit is configured to cause a refrigerant expanded by the expansion section to absorb heat generated by a heat generation unit. The heat absorption unit is configured to increase a heat absorption amount in accordance with a reduction in a permissible noise level of the compressor.

[0009] Accordingly, the amount of heat absorbed in the heat absorption unit increases as the allowable noise level of the compressor decreases, so that the desired heating capacity in the heating unit can be ensured even if the compressor working amount (in other words, the compressor speed) is reduced. Therefore, it is possible to suppress the compressor noise while ensuring the necessary heating capacity.

[0010] According to a second aspect of the present disclosure, a heat pump cycle device includes a compressor, a heating unit, an expansion unit, a heat absorption unit, and an upper limit speed determination unit.

[0011] The compressor is configured to suck in, compress, and discharge a refrigerant. The heating unit is configured to heat an object to be heated by using a refrigerant discharged from the compressor as a heat source. The expansion unit is configured to expand a refrigerant flowing out of the heating unit. The heat absorption unit is configured to cause a refrigerant expanded by the expansion section to absorb heat generated by a heat generation unit. The upper-limit speed determination unit is configured to determine an upper-limit speed of the compressor.

[0012] The upper-limit speed determination unit lowers the upper-limit speed according to a reduction in the permissible noise level of the compressor. The heat absorption unit is configured to increase a heat absorption amount according to a reduction in the permissible noise level of the compressor.

[0013] This can produce the same effects as those of the first aspect. Brief description of the drawings

[0014] The above object and other objects, features and advantages of the present disclosure will become further apparent from the following detailed description with reference to the accompanying drawings. Fig. 1 is a schematic overall configuration diagram showing a vehicle air conditioner according to a first embodiment. Fig. 2 is a schematic configuration diagram showing an indoor air conditioning unit according to the first embodiment. Fig. 3 is a block diagram showing an electric control unit of the vehicle air conditioner according to the first embodiment. Fig. 4 is a control characteristic graph used in determination of allowable compressor noise in the first embodiment. Fig. 5 is a control characteristic graph used in determining a target chiller inlet water temperature in the first embodiment. Fig. 6 is a graph showing a relationship between a chiller inlet water temperature, a compressor rotational speed, a chiller heat absorption amount, and the work amount of the compressor in the first embodiment. Fig. 7 is a schematic overall configuration diagram showing a flow of refrigerant in a simple hot gas dehumidification-heating mode and a cooling-hot gas heating mode of a heat pump cycle in the first embodiment. Fig. 8 is a Mollier diagram showing a state change of a refrigerant in the simple hot gas heating mode of the heat pump cycle in the first embodiment. Fig. 9 is a schematic overall configuration diagram showing a vehicle air conditioner according to a second embodiment. Fig. 10 is a schematic overall configuration diagram showing a vehicle air conditioner according to a third embodiment. Fig. 11 is a schematic overall configuration diagram showing a vehicle air conditioner according to a fourth embodiment. Fig. 12 is a graph showing a relationship between a target chiller superheat degree and a chiller heat absorption amount in a fifth embodiment. Description of the embodiments

[0015] Hereinafter, embodiments for implementing the present disclosure will be described with reference to drawings. In the respective embodiments, parts corresponding to items already described in the previous embodiment are given reference numerals identical to the reference numerals of the items already described. Therefore, the same description will be omitted depending on the circumstances. In a case where only a part of the configuration is described in each embodiment, other embodiments described before may be applied to other parts of the configuration. Also, it is possible to partially combine the embodiments even if it is not explicitly described, as long as there is no problem in the combination as well as the combination of the parts where it is specifically and explicitly described that the combination is possible. (First embodiment)

[0016] A first embodiment of a heat pump cycle device according to the present disclosure will be described with reference to Fig. 1 to 8. In the present embodiment, the heat pump cycle device according to the present disclosure is applied to a vehicle air conditioner 1 mounted on an electric vehicle. The electric vehicle is a vehicle that obtains driving power from an electric motor. The vehicle air conditioner 1 performs air conditioning in a vehicle interior, which is a space to be air-conditioned, and adjusts the temperature of an in-vehicle device. Therefore, the vehicle air conditioner 1 can be referred to as an air conditioner with a temperature adjustment function of an in-vehicle device or as a temperature adjustment device of an in-vehicle device with an air conditioning function.

[0017] The vehicle air conditioning system 1 includes a heat pump circuit 10, a high-temperature side heat medium circuit 30, a low-temperature side heat medium circuit 40, an interior air conditioning unit 50, a control device 60, and the like.

[0018] The heat pump circuit 10, which is Fig. 1 is a vapor compression refrigeration cycle that adjusts the temperatures of ventilation air blown into the vehicle interior, a high-temperature side heat medium circulating in the high-temperature side heat medium circuit 30, and a low-temperature side heat medium circulating in the low-temperature side heat medium circuit 40.

[0019] The heat pump circuit 10 is configured to switch the refrigerant circuit according to different operating modes to perform air conditioning within the vehicle interior. The heat pump circuit 10 uses an HFO refrigerant (specifically, R1234yf) as the refrigerant. The heat pump circuit 10 forms a subcritical refrigerant circuit in which the pressure of a high-pressure side refrigerant does not exceed the critical pressure of the refrigerant.

[0020] A refrigeration oil for lubricating a compressor 11 is mixed into the refrigerant. The refrigerant oil is a PAG oil (i.e., a polyalkylene glycol oil) compatible with a liquid-phase refrigerant, or a POE (i.e., a polyol ester). A portion of the refrigerant oil circulates along with the refrigerant in the heat pump circuit 10.

[0021] Compressor 11 draws in, compresses, and discharges the refrigerant in heat pump circuit 10. Compressor 11 is an electric compressor that uses an electric motor to rotate a fixed-capacity compression mechanism with a fixed discharge rate. The refrigerant discharge rate (i.e., the rotational speed) of compressor 11 is controlled by a control signal transmitted from a controller 60.

[0022] The compressor 11 is provided in a drive unit chamber formed on a front side of the vehicle interior. The drive unit chamber forms a space in which at least a part of a device (for example, a motor generator as an electric traction motor) is provided, which is used to generate or regulate a driving force for driving the vehicle.

[0023] The inlet port side of a first three-way node 12a is connected to a discharge port of the compressor 11. The first three-way node 12a has three inlet / outlet ports that communicate with each other. As the first three-way node 12a, a node portion formed by joining a plurality of tubes or a node portion formed by providing a plurality of refrigerant passages in a metal block or a resin block can be used.

[0024] The heat pump cycle 10 includes a second three-way node 12b through a sixth three-way node 12f. The basic configuration of each of the second three-way node 12b, a third three-way node 12c, a fourth three-way node 12d, a fifth three-way node 12e, and a sixth three-way node 12f is the same as that of the first three-way node 12a. Furthermore, in embodiments to be described later, the basic configuration of each three-way node is similar to that of the first three-way node 12a.

[0025] In each of these three-way nodes, if one of the three inflow and outflow ports is used as an inflow port and the remaining two are used as outflow ports, the refrigerant flow is branched. If two of the three inflow and outflow ports are used as inflow ports and the remaining one is used as an outflow port, the refrigerant flows are combined. The first three-way node 12a is a branch section that branches the flow of the discharge refrigerant discharged from the compressor 11.

[0026] The inlet side of a refrigerant passage in a water / refrigerant heat exchanger 13 is connected to an outlet port of the first three-way node 12a. Another outlet port of the first three-way node 12a is connected to an inlet port of the sixth three-way node 12f.

[0027] The refrigerant passage from the other outlet port of the first three-way node 12a to an inlet port of the sixth three-way node 12f is a bypass passage 21c. A bypass-side flow rate regulating valve 14d is provided in the bypass passage 21c.

[0028] The bypass-side flow rate regulating valve 14d is a bypass-side expansion unit that expands a discharge refrigerant (i.e., the other of the discharge refrigerant branched at the first three-way node 12a) flowing out from the other outlet port of the first three-way node 12a in various operation modes, such as the hot gas air heating mode described later. The bypass-side flow rate regulating valve 14d is a bypass-side flow rate regulating unit that regulates the flow rate (the mass flow rate) of the refrigerant flowing through the bypass passage 21c.

[0029] The bypass-side flow rate regulating valve 14d is an electric variable throttle mechanism including a valve body that changes a throttle opening and an electric actuator (specifically, a stepping motor) as a drive unit that displaces the valve body. The operation of the bypass-side flow rate regulating valve 14d is controlled by a control pulse output from the controller 60.

[0030] The bypass-side flow rate regulating valve 14d has a full-opening function, which acts as a simple refrigerant passage without any refrigerant release action, and a flow rate regulating action by setting the throttle opening to a fully open state. The bypass-side flow rate regulating valve 14d has a full-closing function, which closes the refrigerant passage by setting the throttle opening to a fully closed state.

[0031] The heat pump cycle 10 includes an air heating expansion valve 14a, an air cooling expansion valve 14b, and a cooling expansion valve 14c. Each of the basic configurations of the air heating expansion valve 14a, the air cooling expansion valve 14b, and the cooling expansion valve 14c is similar to that of the bypass-side flow rate regulating valve 14d.

[0032] The refrigerant cycle can be switched by the air heating expansion valve 14a, the air cooling expansion valve 14b, the cooling expansion valve 14c, and the bypass-side flow rate regulating valve 14d, which have a fully closing function. Therefore, the air heating expansion valve 14a, the air cooling expansion valve 14b, the cooling expansion valve 14c, and the bypass-side flow rate regulating valve 14d function as a refrigerant cycle switching unit.

[0033] The air heating expansion valve 14a, the air cooling expansion valve 14b, the cooling expansion valve 14c, and the bypass-side flow rate regulating valve 14d may be configured by combining a variable throttle mechanism that does not have a full-closing function and an on / off valve that opens and closes a throttle passage. In this case, each on / off valve functions as the refrigerant cycle switching unit.

[0034] The water-to-refrigerant heat exchanger 13 is a heat dissipation heat exchange unit that exchanges heat between the high-pressure refrigerant discharged from the compressor 11 and the high-temperature-side heat medium circulating in the high-temperature-side heat medium circuit 30 to dissipate heat from the refrigerant to the high-temperature-side heat medium. The water-to-refrigerant heat exchanger 13 is a heating unit that uses the refrigerant discharged from the compressor 11 as a heat source to heat the high-temperature-side heat medium, which is an object to be heated.

[0035] In the present embodiment, a so-called subcooling heat exchanger is used as the water-refrigerant heat exchanger 13. For this reason, a condensing section 13a, a receiver 13b, and a subcooling section 13c are provided in the refrigerant passage of the water-refrigerant heat exchanger 13.

[0036] The condensing section 13a is a condensing heat exchange unit that exchanges heat between the high-pressure refrigerant discharged from the compressor 11 and the high-pressure side heat medium to condense the high-pressure refrigerant. The accumulator 13b is a high-pressure side gas / liquid separation unit that separates the refrigerant flowing out of the condensing section 13a into a gas and a liquid and stores the separated liquid-phase refrigerant as excess refrigerant in the cycle. The subcooling section 13c is a subcooling heat exchange unit that exchanges heat between the liquid-phase refrigerant flowing out of the accumulator 13b and the high-temperature side heat medium to subcool the liquid-phase refrigerant.

[0037] An inlet port side of the second three-way node 12b is connected to an outlet port of the refrigerant passage of the water-refrigerant heat exchanger 13 (specifically, the outlet port of the subcooling section 13c). An inlet side of an air-heating expansion valve 14a is connected to an outlet port of the second three-way node 12b. An inlet port side of a four-way node 12x is connected to the other outlet port of the second three-way node 12b.

[0038] The refrigerant passage from the other outlet port of the second three-way node 12b to an inlet port of the four-way node 12x is a dehumidification passage 21a. A dehumidification on / off valve 22a is provided in the dehumidification passage 21a.

[0039] The dehumidification on / off valve 22a is an on / off valve that opens and closes the dehumidification passage 21a. The dehumidification on / off valve 22a is an electromagnetic valve whose opening and closing operation is controlled by a control voltage output from the controller 60. The dehumidification on / off valve 22a can switch the refrigerant cycle by opening and closing the dehumidification passage 21a. Therefore, the dehumidification on / off valve 22a is a refrigerant cycle switching unit.

[0040] The four-way node 12x is a node section that has four inflow and outflow ports that communicate with each other. A node section formed in the same way as the three-way node described above can be used as the four-way node 12x. A node section formed by combining two three-way nodes can be used as the four-way node 12x.

[0041] The air-heating expansion valve 14a is an outdoor heat exchanger-side expansion unit that expands the refrigerant flowing into the outdoor heat exchanger 15 in an air-heating mode and the like among various operating modes. The air-heating expansion valve 14a is a flow rate regulating unit on the outdoor heat exchanger side that regulates the flow rate (mass flow rate) of the refrigerant flowing into the outdoor heat exchanger 15.

[0042] A refrigerant inlet side of the outdoor heat exchanger 15 is connected to an outlet of the air-heating expansion valve 14a. The outdoor heat exchanger 15 is an outdoor air heat exchange unit that exchanges heat between the refrigerant flowing out of the air-heating expansion valve 14a and outside air blown by an outside air fan (not shown). The outdoor heat exchanger 15 is provided on the front side of the power unit chamber. For this reason, during vehicle travel, the airflow flowing into the power unit chamber through a grille can be blown against the outdoor heat exchanger 15.

[0043] An inlet port of the third three-way node 12c is connected to the refrigerant outlet of the outdoor heat exchanger 15. Another inlet port side of the four-way node 12x is connected to an outlet port of the third three-way node 12c via a first check valve 16a. Another outlet port of the third three-way node 12c is connected to an inlet port of the fourth three-way node 12d.

[0044] The refrigerant passage from the other outlet port of the third three-way node 12c to an inlet port of the fourth three-way node 12d is an air heating passage 21b. An air heating on / off valve 22b is provided in the air heating passage 21b.

[0045] The air heating on / off valve 22b is an on / off valve that opens and closes the air heating passage 21b. The basic configuration of the air heating on / off valve 22b is the same as that of the dehumidification on / off valve 22a. Therefore, the air heating on / off valve 22b is a refrigerant cycle switching unit. The basic configuration of each on / off valve described in the embodiments to be described later is also similar to that of the dehumidification on / off valve 22a.

[0046] The first check valve 16a allows the refrigerant to flow from the third three-way node 12c side to the four-way node 12x side and prevents the refrigerant from flowing from the four-way node 12x side to the third three-way node 12c side.

[0047] The refrigerant inflow port side of an indoor evaporator 18 is connected to an outflow port of the four-way node 12x via the air cooling expansion valve 14b.

[0048] The air-cooling expansion valve 14b is an expansion unit on the indoor evaporator side that expands the refrigerant flowing into the indoor evaporator 18 in an air-cooling mode, a hot-gas dehumidification / air-heating mode, or the like among the various operating modes. Therefore, the air-cooling expansion valve 14b serves as a heating-unit-side expansion unit in the hot-gas dehumidification / air-heating mode or the like. The air-cooling expansion valve 14b is also a flow rate regulating unit on the indoor evaporator side that regulates the flow rate (mass flow rate) of the refrigerant flowing into the indoor evaporator 18.

[0049] The interior evaporator 18 is provided in an air conditioning housing 51 of the interior air conditioning unit 50, which is Fig. 2. The interior evaporator 18 is an air-cooling heat exchange unit that exchanges heat between the low-pressure refrigerant expanded by the air-cooling expansion valve 14b and the ventilation air blown toward the vehicle interior from an interior blower 52. In the interior evaporator 18, the ventilation air is cooled by evaporating the low-pressure refrigerant to exhibit the heat absorption action.

[0050] An inflow port side of the fifth three-way node 12e is connected to a refrigerant outflow port of the indoor evaporator 18 via a second check valve 16b. The second check valve 16b allows the refrigerant to flow from the refrigerant outflow port side of the indoor evaporator 18 to the fifth three-way node 12e side and prevents the refrigerant from flowing from the fifth three-way node 12e side to the refrigerant outflow port side of the indoor evaporator 18.

[0051] An inflow port side of a refrigerant passage in a chiller 20 is connected to another outflow port of the four-way node 12x via the cooling expansion valve 14c.

[0052] The cooling expansion valve 14c is a chiller-side expansion unit that expands the refrigerant flowing into the chiller 20, for example, in a cooling and air cooling mode, the hot gas air heating mode, or the like, from the various operating modes. Therefore, in the hot gas air heating mode or the like, the cooling expansion valve 14c serves as a heating unit-side expansion unit. The cooling expansion valve 14c is also a chiller-side flow rate regulating unit that regulates the flow rate (mass flow rate) of the refrigerant flowing into the chiller 20.

[0053] The chiller 20 is a temperature-regulating heat exchange unit that exchanges heat between the low-pressure refrigerant expanded by the cooling expansion valve 14c and the low-temperature side heat medium circulating in the low-temperature side heat medium circuit 40. In the chiller 20, the low-pressure refrigerant is evaporated to exert a heat absorption effect, so that the heat held by the low-temperature heat medium is absorbed by the low-pressure refrigerant.

[0054] The other inlet port side of the fourth three-way node 12d is connected to an outlet port of the refrigerant passage in the chiller 20. The other inlet port side of the fifth three-way node 12e is connected to an outlet port of the fourth three-way node 12d. The other inlet port side of the sixth three-way node 12f is connected to an outlet port of the fifth three-way node 12e. An inlet port side of the compressor 11 is connected to an outlet port of the sixth three-way node 12f.

[0055] Accordingly, in the hot gas air heating mode or the like, the sixth three-way node 12f serves as a merging unit that merges the flow of the heating unit-side refrigerant flowing out of the heating unit-side expansion unit and the flow of the bypass-side refrigerant flowing out of the bypass-side flow rate regulating valve 14d, and causes the merged flow to flow to the inflow port side of the compressor 11.

[0056] The refrigerant passage from the discharge port of the sixth three-way node 12f to the suction port of the compressor 11 is a suction-side passage 21d, which forms a suction-side passage.

[0057] The high-temperature-side heat medium circuit 30 is a heat medium circulation circuit that circulates the high-temperature-side heat medium. In the present embodiment, an aqueous ethylene glycol solution is used as the high-temperature-side heat medium. The high-temperature-side heat medium circuit 30 includes the heat medium passage of the water-refrigerant heat exchanger 13, a high-temperature-side pump 31, a heater core 32, and the like.

[0058] The high-temperature-side pump 31 is a high-temperature-side heat medium pressure transfer unit that pressurizes the high-temperature-side heat medium flowing out of the heat medium passage of the water-refrigerant heat exchanger 13 to the heat medium inlet side of the heater core 32. The high-temperature-side pump 31 is an electric pump whose rotational speed (i.e., pumping capacity) is controlled by a control voltage output from the controller 60.

[0059] The heater core 32 is a heater core heat exchanger that exchanges heat between the high-temperature side heat medium heated by the water / refrigerant heat exchanger 13 and the ventilation air passing through the interior evaporator 18 to heat the ventilation air. The heater core 32 is provided in the air conditioning case 51 of the interior air conditioning unit 50. The inlet side of a heat medium passage of the water / refrigerant heat exchanger 13 is connected to the heat medium outlet of the heater core 32.

[0060] Therefore, the constituent devices of the water / refrigerant heat exchanger 13 and the high-temperature side heat medium circuit 30 of the present embodiment are heating units that heat ventilation air as an object to be heated by using a discharge refrigerant branched at the first three-way node 12a as a heat source.

[0061] Next, the low-temperature-side heat medium circuit 40 will be described. The low-temperature-side heat medium circuit 40 is a heat medium circuit that circulates the low-temperature-side heat medium. In the present embodiment, the same type of fluid as the high-temperature-side heat medium is used as the low-temperature-side heat medium. A low-temperature-side pump 41, a cooling water passage 70a of an electric heater 70, the heat medium passage of the chiller 20, and the like are connected to the low-temperature-side heat medium circuit 40.

[0062] The low-temperature-side pump 41 is a low-temperature-side heat medium pressure transfer unit that pressurizes the low-temperature-side heat medium flowing out of the cooling water passage 70a of the electric heater 70 to the heat medium passage inlet side of the chiller 20. The basic configuration of the low-temperature-side pump 41 is similar to that of the high-temperature-side pump 31. The inlet side of the cooling water passage 70a of the electric heater 70 is connected to the heat medium passage outlet side of the chiller 20. The electric heater 70 is a heating element that generates heat when electric power is supplied to heat the high-temperature-side heat medium. The heat medium heating capacity (i.e., the heat generation amount) of the electric heater 70 is controlled by a control signal output from the controller 60.

[0063] The cooling water passage 70a of the electric heater 70 is a cooling water passage configured to cool the electric heater 70 by causing the low-temperature side heat medium cooled by the chiller 20 to flow therethrough.

[0064] The passage configuration of the cooling water passage 70a is a passage configuration in which a plurality of passages are connected in parallel within the battery-specific casing. As a result, all battery cells can be evenly cooled in the cooling water passage 70a. The inlet port side of the low-temperature side pump 41 is connected to the outlet of the cooling water passage 70a.

[0065] Next, the interior air conditioning unit 50 is described with respect to Fig. 2. The interior air conditioning unit 50 is a unit in which a plurality of components are integrated to blow ventilation air, whose temperature has been adjusted to an appropriate temperature for air conditioning the vehicle interior, to an appropriate location within the vehicle interior. The interior air conditioning unit 50 is provided within an instrument panel (the instrument panel) at the frontmost part of the vehicle interior.

[0066] The interior air conditioning unit 50 is configured by accommodating the interior blower 52, the interior evaporator 18, the heater core 32, and the like in the air conditioning case 51, which forms an air passage for ventilation air. The air conditioning case 51 is made of a resin (e.g., polypropylene) with a certain degree of elasticity and excellent strength.

[0067] An inside-outside air switching device 53 is provided on the most upstream side of a ventilation air flow in the air conditioning case 51. The inside-outside air switching device 53 alternately introduces inside air (i.e., air inside the vehicle interior) and outside air (i.e., air outside the vehicle interior) into the air conditioning case 51. Operation of the inside-outside air switching device 53 is controlled by a control signal output from the controller 60.

[0068] The interior fan 52 is provided on the downstream side of the ventilation air flow of the inside-outside air switching device 53. The interior fan 52 is an air blowing unit that blows air drawn in by the inside-outside air switching device 53 toward the vehicle interior. The rotational speed (i.e., a blowing capacity) of the interior fan 52 is controlled by a control voltage output from the controller 60.

[0069] The interior blower 18 and the heater core 32 are arranged on the downstream side of the ventilation air flow of the interior blower 52. The interior evaporator 18 is provided on the upstream side of the ventilation air flow of the heater core 32. A cold air bypass passage 55, through which the ventilation air that has passed through the interior evaporator 18 flows while bypassing the heater core 32, is formed in the air conditioning case 51.

[0070] An air mix door 54 is provided on the downstream side of the ventilation air flow of the indoor evaporator 18 in the air conditioning case 51 and on the upstream side of the ventilation air flow of the heater core 32 and the cold air bypass passage 55 in the air conditioning case 51.

[0071] The air mix damper 54 adjusts the air volume ratio between the air volume of the ventilation air passing through the heater core 32 and the air volume of the ventilation air passing through the cold air bypass passage 55 for the ventilation air that has passed through the interior evaporator 18. Operation of an actuator for driving the air mix damper 54 is controlled by a control signal output from the controller 60.

[0072] A mixing space 56 is formed on the downstream side of the ventilation air flow of the heater core 32 and the cold air bypass passage 55. The mixing space 56 is a space where the ventilation air heated by the heater core 32 and the ventilation air that has passed through the cold air bypass passage 55 and has not been heated are mixed.

[0073] Therefore, in the interior air conditioning unit 50, the temperature of the ventilation air (ie, air conditioning air) mixed in the mixing space 56 and blown into the vehicle interior can be adjusted by adjusting the opening of the air mix door 54. The air mix door 54 of the present embodiment is an air flow rate regulating unit that regulates the flow rate of the ventilation air subjected to heat exchange at the heater core 32.

[0074] A plurality of opening holes (not shown) for blowing air conditioning air to various locations in the vehicle interior are formed at the most downstream portion of the ventilation air flow in the air conditioning case 51. A blow mode door (not shown) that opens and closes each opening hole is provided in each of the plurality of opening holes. Operation of an actuator for driving the blow mode door is controlled by a control signal output from the controller 60.

[0075] Therefore, in the interior air conditioning unit 50, the air conditioning air adjusted to an appropriate temperature can be blown to appropriate locations in the vehicle interior by switching the openings opened and closed by the blow mode door.

[0076] Next, an electrical control unit of the present embodiment will be described. The control device 60 includes a known microcontroller including a central processing unit (i.e., a CPU), a read-only memory (i.e., a ROM), a working memory (i.e., a RAM), and surrounding circuits thereof. The control device 60 performs various calculations and operations based on a control program stored in the ROM. The control device 60 then controls the operations of the various control target devices 11, 14a to 14d, 22a, 22b, 31, 41, 52, 53, and the like connected to the output side based on the calculation and processing results.

[0077] As shown in the block diagram of Fig. 3, a control sensor group is connected to the input side of the controller 60. The control sensor group includes an indoor air temperature sensor 61a, an outdoor air temperature sensor 61b, an irradiance sensor 61c, a discharge refrigerant temperature sensor 62a, a high-pressure side refrigerant temperature and pressure sensor 62b, an outdoor unit-side refrigerant temperature and pressure sensor 62c, an evaporator temperature sensor 62d, a chiller-side refrigerant temperature and pressure sensor 62e, a suction refrigerant temperature sensor 62f, a high-temperature side heat medium temperature sensor 63a, a low-temperature side heat medium temperature sensor 63b, a heater temperature sensor 64, and an air-conditioning air temperature sensor 65.

[0078] The inside air temperature sensor 61a is an inside air temperature detection unit that detects a vehicle interior temperature (an inside air temperature) Tr. The outside air temperature sensor 61b is an outside air temperature detection unit that detects the vehicle outside air temperature (an outside air temperature) Tam. The irradiation sensor 61c is an irradiation amount detection unit that detects an irradiation amount As of irradiation radiating into the vehicle interior.

[0079] The discharge refrigerant temperature sensor 62a is a discharge refrigerant temperature detecting unit that detects a discharge refrigerant temperature Td of the discharge refrigerant discharged from the compressor 11.

[0080] The evaporator temperature sensor 62d is an evaporator temperature detection unit that detects a refrigerant evaporation temperature (an evaporator temperature) Tefin in the interior evaporator 18. Specifically, the evaporator temperature sensor 62d detects a heat exchange fin temperature of the interior evaporator 18.

[0081] The high-pressure-side refrigerant temperature and pressure sensor 62b is a high-pressure-side refrigerant temperature / pressure detection unit that detects a high-pressure-side refrigerant temperature T1, which is the temperature of the refrigerant flowing out of the water-refrigerant heat exchanger 13, and a discharge refrigerant pressure Pd, which is the pressure of the refrigerant flowing out of the water-refrigerant heat exchanger 13. The discharge refrigerant pressure Pd can be used as the pressure of the discharge refrigerant discharged from the compressor 11.

[0082] The outdoor unit-side refrigerant temperature and pressure sensor 62c is an outdoor unit-side refrigerant temperature and pressure detection unit that detects an outdoor unit-side refrigerant temperature T2, which is the temperature of the refrigerant flowing out of the outdoor heat exchanger 15, and an outdoor unit-side refrigerant pressure P2, which is the pressure of the refrigerant flowing out of the outdoor heat exchanger 15. Specifically, the temperature and pressure of the refrigerant flowing through the refrigerant passage from the refrigerant outflow port of the outdoor heat exchanger 15 to an inflow port of the third three-way node 12c are detected.

[0083] The chiller-side refrigerant temperature and pressure sensor 62e is a chiller-side refrigerant temperature / pressure detection unit that detects a chiller-side refrigerant temperature Tc, which is the temperature of the refrigerant flowing out of the refrigerant passage in the chiller 20, and a chiller-side refrigerant pressure Pc, which is the pressure of the refrigerant flowing out of the refrigerant passage in the chiller 20. The chiller-side refrigerant pressure Pc can be used as a suction refrigerant pressure Ps, which is the pressure of the suction refrigerant drawn into the compressor 11. Therefore, the chiller-side refrigerant temperature and pressure sensor 62e of the present embodiment is a suction pressure detection unit.

[0084] In the present embodiment, as the refrigerant temperature and pressure sensor, a detection unit in which the pressure detection unit and the temperature detection unit are integrated is used, but it is a matter of course that the pressure detection unit and the temperature detection unit configured separately may be used.

[0085] The suction refrigerant temperature sensor 62f is a suction refrigerant temperature detecting unit provided in the suction side passage 21d and detects a suction refrigerant temperature Ts, which is the temperature of the suction refrigerant sucked into the compressor 11.

[0086] The high-temperature side heat medium temperature sensor 63a is a high-temperature side heat medium temperature detection unit that detects a high-temperature side heat medium temperature TWH, which is the temperature of the high-temperature side heat medium flowing into the heater core 32. The low-temperature heat medium temperature sensor 63b is a low-temperature heat medium temperature detection unit that detects a low-temperature heat medium temperature TWL, which is the temperature of the low-temperature heat medium flowing in the cooling water passage 70a of the electric heater 70.

[0087] The heater temperature sensor 64 is a battery temperature detection unit that detects a heater temperature TB, which is the temperature of the electric heater 70.

[0088] The air conditioning air temperature sensor 65 is an air conditioning air temperature detection unit that detects a ventilation air temperature TAV of the air blown from the mixing chamber 56 into the vehicle interior. The ventilation air temperature TAV is an object temperature of the ventilation air as an object to be heated.

[0089] As in Fig. As shown in Figure 3, an operation panel 69, provided near the instrument panel at the front of the vehicle interior, is connected to the input side of the control device 60 in a wired or wireless manner. Operation signals from various operation switches provided on the operation panel 69 are input to the control device 60.

[0090] Specific examples of the various operation switches provided on the operation panel 69 include an automatic switch, an air conditioning switch, an air volume adjustment switch, and a temperature adjustment switch.

[0091] The automatic switch is an automatic control setting unit that sets or cancels the automatic control operation of the vehicle air conditioner 1. The air conditioning switch is a cooling request unit that requests the interior evaporator 18 to cool the ventilation air. The air volume setting switch is an air volume setting unit that manually adjusts the air blowing volume of the interior blower 62. The temperature setting switch is a temperature setting section for setting a set temperature Tset of the vehicle interior.

[0092] The control device 60 of the present embodiment is configured integrally with a control device that controls various control target devices connected to an output side thereof. Therefore, a configuration (hardware and software) that controls the operation of each device to be controlled constitutes a control device that controls the operation of each device to be controlled.

[0093] For example, in the control device 60, the configuration that controls the refrigerant discharge capacity of the compressor 11 configures a discharge capacity control unit 60a.

[0094] The discharge capacity control unit 60a controls the refrigerant discharge capacity of the compressor 11 so that the rotational speed of the compressor 11 does not exceed a maximum speed and an upper limit speed. The maximum speed is determined based on the durability of the compressor 11. The upper limit speed is a speed determined based on an allowable noise level of the compressor 11. That is, since the noise of the compressor 11 increases as the rotational speed of the compressor 11 increases, the rotational speed of the compressor 11 at which the noise of the compressor 11 reaches the allowable noise level is set as the upper limit speed. Therefore, the discharge capacity control unit 60a also functions as an upper limit speed determining unit that determines the upper limit speed of the compressor 11.

[0095] The configuration for controlling the operation of the heating-unit-side expansion unit (in the present embodiment, the air heating expansion valve 14a and the air cooling expansion valve 14b, as well as the cooling expansion valve 14c) configures a heating-unit-side control unit 60b. The configuration for controlling the operation of the bypass-side flow rate regulating valve 14d configures a bypass-side control unit 60c. The target heating capacity determination unit 60d determines a target heating capacity (in other words, the target heating capacity) in the indoor air conditioning unit 50. For example, a high-temperature-side target heat medium temperature (TWHO) is determined.

[0096] Next, the operation of the vehicle air conditioner 1 according to the present embodiment with the above configuration will be described. In the vehicle air conditioner of the present embodiment, various operation modes are switched to perform air conditioning of the vehicle interior. The switching of the operation mode is performed by executing a control program stored in advance in the controller 60. Various operation modes are described below.

[0097] First, an operation mode in which the refrigerant does not flow through the bypass passage 21c will be described. The operation modes in which the refrigerant is not circulated through the bypass passage 21c include (a) an air cooling mode, (b) a serial dehumidification-air heating mode, (c) an outside air heat absorption-air heating mode, and (d) a heating-heat absorption-air heating mode. (a) Air cooling mode

[0098] The air cooling mode is an operation mode in which the air in the vehicle interior is cooled by blowing cooled ventilation air into the vehicle interior. In the control program, the air cooling mode is selected primarily in summer when the outside air temperature Tam is relatively high (25°C or higher in the present embodiment).

[0099] In the heat pump cycle 10 in the air-cooling mode, the controller 60 brings the air-heating expansion valve 14a into a fully open state, the air-cooling expansion valve 14b into a throttling state exhibiting a refrigerant release action, brings the cooling expansion valve 14c into a fully closed state, and brings the bypass-side flow rate regulating valve 14d into a fully closed state. Furthermore, the controller 60 closes the dehumidification on / off valve 22a and also closes the air-heating on / off valve 22b.

[0100] Therefore, in the heat pump cycle 10 in the air cooling mode, the refrigerant circuit is switched to a refrigerant circuit in which the refrigerant discharged from the compressor 11 circulates in this order through the water / refrigerant heat exchanger 13, the air heating expansion valve 14a in the fully open state, the outdoor heat exchanger 15, the air cooling expansion valve 14b in the throttling state, the indoor evaporator 18, the suction side passage 21d, and the suction port of the compressor 11.

[0101] The controller 60 controls the refrigerant discharge capacity of the compressor 11 such that the evaporator temperature Tefin, detected by the evaporator temperature sensor 62d, approaches a target evaporator temperature TEO. The target evaporator temperature TEO is determined based on the target discharge temperature TAO with reference to a control map stored in advance in the controller 60.

[0102] The target blowout temperature TAO is a target temperature of ventilation air to be blown into the vehicle interior. The target blowout temperature TAO is calculated using the indoor air temperature Tr detected by the indoor air temperature sensor 61a, the outdoor air temperature Tam, the irradiation amount As detected by the irradiation sensor 61c, the setting temperature Tset set by the temperature setting switch, and the like. In the control map, it is determined that the target evaporator temperature TEO increases as the target blowout temperature TAO increases.

[0103] The superheat degree SH of the suction refrigerant can be determined by using the chiller-side refrigerant pressure Pc detected by the chiller-side refrigerant temperature and pressure sensor 62e and the suction refrigerant temperature Ts detected by the suction refrigerant temperature sensor 62f.

[0104] In the high-temperature side heat medium circuit 30 in the air-cooling mode, the controller 60 operates the high-temperature side pump 31 to exhibit a predetermined reference pumping capacity. Therefore, in the high-temperature side heat medium circuit 30 in the air-cooling mode, the heat medium pumped from the high-temperature side pump 31 circulates in this order through the heat medium passage of the water-refrigerant heat exchanger 13, the heater core 32, and the suction port of the high-temperature side pump 31.

[0105] With the interior air conditioning unit 50 in the air-cooling mode, the controller 60 controls the blowing capacity of the interior blower 52 based on the target blowing temperature TAO according to a control map stored in advance in the controller 60. The controller 60 adjusts the opening of the air mix door 54 so that the ventilation air temperature TAV detected by the air-conditioning air temperature sensor 65 approaches the target blowing temperature TAO. Furthermore, the controller 60 appropriately controls the operations of other control target devices.

[0106] Therefore, in the heat pump cycle 10 in the air cooling mode, a vapor compression refrigeration cycle is configured in which the water / refrigerant heat exchanger 13 and the outdoor heat exchanger 15 function as condensers, dissipate the heat of the refrigerant and condense the refrigerant, and the indoor evaporator 18 functions as an evaporator that evaporates the refrigerant.

[0107] In the high-temperature side heat medium circuit 30 in the air cooling mode, the high-temperature side heat medium heated by the water / refrigerant heat exchanger 13 flows into the heater core 32.

[0108] With the interior air conditioning unit 50 in the air cooling mode, the ventilation air supplied by the interior blower 52 is cooled by the interior evaporator 18. The ventilation air cooled by the interior evaporator 18 is reheated by the heater core 32 to approach the target blowout temperature TAO based on the opening of the air mix door 54. The ventilation air at a regulated temperature is blown into the vehicle interior, thus cooling the air in the vehicle interior. (b) Serial dehumidification air heating mode

[0109] The serial dehumidification-air heating mode is an operation mode in which the air in the vehicle interior is dehumidified and heated by reheating cooled and dehumidified ventilation air and blowing the reheated ventilation air into the vehicle interior. In the control program, the serial dehumidification-air heating mode is selected when the outside air temperature Tam is within a predetermined medium to high temperature range (equal to or higher than 10°C and lower than 25°C in the present embodiment).

[0110] In the heat pump cycle 10 in the serial dehumidification-air heating mode, the controller 60 places the air heating expansion valve 14a in the throttling state, the air cooling expansion valve 14b in the throttling state, the cooling expansion valve 14c in the fully closed state, and the bypass-side flow rate regulating valve 14d in the fully closed state. Furthermore, the controller 60 closes the dehumidification on / off valve 22a and also closes the air heating on / off valve 22b.

[0111] Therefore, in the heat pump cycle 10 in the serial dehumidification-air heating mode, the refrigerant circuit is switched to a refrigerant circuit in which the refrigerant discharged from the compressor 11 circulates in this order through the water / refrigerant heat exchanger 13, the air heating expansion valve 14a in the throttling state, the outdoor heat exchanger 15, the air cooling expansion valve 14b in the throttling state, the indoor evaporator 18, the suction side passage 21d, and the suction port of the compressor 11.

[0112] Furthermore, the controller 60 controls the throttle opening of the air-heating expansion valve 14a and the throttle opening of the air-cooling expansion valve 14b with reference to the control map stored in advance in the controller 60. In the control map, the throttle opening of the air-heating expansion valve 14a and the throttle opening of the air-cooling expansion valve 14b are determined in such a manner that the superheat degree SH of the intake refrigerant approaches the reference superheat degree KSH.

[0113] In the high-temperature side heat medium circuit 30 in the serial dehumidification air heating mode, the controller 60 operates the high-temperature side pump 31 as in the air cooling mode.

[0114] When the indoor air conditioning unit 50 is in the serial dehumidification-air heating mode, the controller 60 controls the ventilation power of the indoor blower 52 and the opening of the air mix door 54 as in the air cooling mode. Furthermore, the controller 60 appropriately controls the operations of the other control target devices.

[0115] Therefore, in the heat pump cycle 10 in the serial dehumidification air heating mode, a vapor compression refrigeration cycle is configured in which the water / refrigerant heat exchanger 13 functions as a condenser and the indoor evaporator 18 functions as an evaporator.

[0116] Furthermore, in the serial dehumidification air heating mode, when the saturation temperature of the refrigerant in the outdoor heat exchanger 15 is higher than the outside air temperature Tam, the outdoor heat exchanger 15 functions as a condenser. When the saturation temperature of the refrigerant in the outdoor heat exchanger 15 is lower than the outside air temperature Tam, the outdoor heat exchanger 15 functions as an evaporator.

[0117] In the high-temperature side heat medium circuit 30 in the serial dehumidification air heating mode, the high-temperature side heat medium heated by the water / refrigerant heat exchanger 13 flows into the heater core 32.

[0118] In the interior air conditioning unit 50 in the serial dehumidification-air heating mode, the ventilation air supplied by the interior blower 52 is cooled and dehumidified by the interior evaporator 18. The ventilation air cooled and dehumidified by the interior evaporator 18 is reheated by the heater core 32 to approach the target blowout temperature TAO based on the opening of the air mix door 54. The ventilation air at a regulated temperature is blown into the vehicle interior, so that the air in the vehicle interior is dehumidified and heated. (c) Outdoor air heat absorption air heating mode

[0119] The outside air heat absorption air heating mode is an operation mode in which the vehicle interior is heated by blowing heated ventilation air into the vehicle interior. In the control program, the outside air heat absorption air heating mode is selected primarily in winter when the outside air temperature Tam is relatively low (equal to or higher than -10°C and lower than 0°C in the present embodiment).

[0120] When the heat pump cycle 10 is in the outside air heat absorption air heating mode, the controller 60 places the air heating expansion valve 14a in the throttling state, the air cooling expansion valve 14b in the fully closed state, the cooling expansion valve 14c in the fully closed state, and the bypass-side flow rate regulating valve 14d in the fully closed state. Furthermore, the controller 60 closes the dehumidification on / off valve 22a and also closes the air heating on / off valve 22b.

[0121] Therefore, in the heat pump cycle 10 in the outdoor air heat absorption air heating mode, the refrigerant circuit is switched to a refrigerant circuit in which the refrigerant discharged from the compressor 11 circulates in this order through the water / refrigerant heat exchanger 13, the air heating expansion valve 14a in the throttling state, the outdoor heat exchanger 15, the air heating passage 21b, the suction side passage 21d, and the suction port of the compressor 22.

[0122] Furthermore, the controller controls the refrigerant discharge capacity of the compressor 11 such that the discharge refrigerant pressure Pd detected by the high-pressure side refrigerant temperature and pressure sensor 62b approaches a target high pressure PDO. The target high pressure PDO is determined based on the target discharge temperature TAO with reference to a control map stored in advance in the controller 60. In the control map, the target high pressure PDO is determined to increase as the target discharge temperature TAO increases.

[0123] The control device 60 also controls the throttle opening of the air heating expansion valve 14a in such a manner that the superheat degree SH of the suction refrigerant approaches the reference superheat degree KSH.

[0124] In the high-temperature side heat medium circuit 30 in the outside air heat absorption air heating mode, the controller 60 operates the high-temperature side pump 31 as in the air cooling mode.

[0125] When the indoor air conditioning unit 50 is in the outside air heat absorption air heating mode, the controller 60 controls the blowing capacity of the indoor blower 52 and the opening of the air mix door 54 as in the air cooling mode. Furthermore, the controller 60 appropriately controls the operations of the other control target devices.

[0126] Therefore, in the heat pump cycle 10 in the outdoor air heat absorption air heating mode, a vapor compression refrigeration cycle is configured in which the water / refrigerant heat exchanger 13 functions as a condenser and the outdoor heat exchanger 15 functions as an evaporator.

[0127] In the outside air heat absorption air heating mode, the high-temperature side heat medium heated by the water / refrigerant heat exchanger 13 flows into the heater core 32 as in the air cooling mode.

[0128] In the interior air conditioning unit 50 in the outside air heat absorption air heating mode, the ventilation air blown from the interior blower 52 passes through the interior evaporator 18. The ventilation air that has passed through the interior evaporator 18 is heated by the heater core 32 depending on the opening of the air mix door 54 to approach the target blowout temperature TAO. The temperature-adjusted ventilation air is blown into the vehicle interior, thus heating the vehicle interior. (d) Heating-heat absorption-air heating mode

[0129] The heater heat absorption air heating mode is an operation mode in which heat generated by the electric heater 70 is used as a heat source to blow heated air into the vehicle interior, thereby heating the vehicle interior. In the control program, the outside air heat absorption air heating mode is selected mainly in winter when the outside air temperature Tam is comparatively low (equal to or higher than -10°C and lower than 0°C in the present embodiment).

[0130] When the heat pump cycle 10 is in the heating-heat absorption air heating mode, the controller 60 brings the air heating expansion valve 14a to the fully closed state, brings the air cooling expansion valve 14b to the fully closed state, brings the cooling expansion valve 14c to the throttling state, and brings the bypass-side flow rate regulating valve 14d to the fully closed state. Furthermore, the controller 60 closes the dehumidification on / off valve 22a and also closes the air heating on / off valve 22b.

[0131] For this reason, in the heat pump cycle 10 in the heating heat absorption air heating mode, the refrigerant cycle is switched to a refrigerant cycle in which a refrigerant discharged from the compressor 11 circulates in this order through the water / refrigerant heat exchanger 13, the throttled cooling expansion valve 14c, the chiller 20, the suction side passage 21d, and the suction port of the compressor 11.

[0132] Furthermore, the controller 60 controls the refrigerant discharge capacity of the compressor 11 such that the discharge refrigerant pressure Pd detected by the high-pressure side refrigerant temperature and pressure sensor 62b approaches a target high pressure PDO. The target high pressure PDO is determined based on the target discharge temperature TAO with reference to a control map stored in advance in the controller 60. In the control map, the target high pressure PDO is determined to increase as the target discharge temperature TAO increases.

[0133] The controller 60 can control the refrigerant discharge capacity of the compressor 11 so that the high-temperature-side heat medium temperature TWH detected by the high-temperature-side heat medium temperature sensor 63a approaches the high-temperature-side target heat medium temperature TWHO. The high-temperature-side target heat medium temperature TWHO is determined based on the target discharge temperature TAO with reference to a control map stored in advance in the controller 60. In the control map, a high-temperature-side target heat medium temperature TWO is determined to be increased as the target discharge temperature TAO increases. The high-temperature-side target heat medium temperature TWHO is an index indicating a target heating capacity (in other words, a target air heating capacity) in the water-refrigerant heat exchanger 13 (in other words, the heater core 32).

[0134] The control device 60 also controls the throttle opening of the air heating expansion valve 14a in such a way that the superheat degree SH of the refrigerant approaches the reference superheat degree KSH.

[0135] In the high-temperature side heat medium circuit 30 in the heating-air heat absorption-air heating mode, the controller 60 operates the high-temperature side pump 31 as in the simple air cooling mode.

[0136] When the interior air conditioning unit 50 is in the heating-heat absorption air-heating mode, the controller 60 controls the blowing capacity of the interior blower 52 and the opening of the air mix door 54 as in the air-cooling mode. Furthermore, the controller 60 appropriately controls the operations of the other control target devices.

[0137] Therefore, in the heat pump cycle 10 in the heating heat absorption air heating mode, a vapor compression refrigeration cycle is configured in which the water / refrigerant heat exchanger 13 functions as a condenser and the chiller 20 functions as an evaporator.

[0138] In the heating heat absorption air heating mode, the high-temperature side heat medium heated by the water / refrigerant heat exchanger 13 flows into the heater core 32 as in the air cooling mode.

[0139] In the interior air conditioning unit 50 in the heating heat absorption air heating mode, the ventilation air blown from the interior blower 52 passes through the interior evaporator 18. The ventilation air that has passed through the interior evaporator 18 is heated by the heater core 32 depending on the opening of the air mix door 54 to approach the target blowout temperature TAO. The temperature-adjusted ventilation air is blown into the vehicle interior, thus heating the vehicle interior.

[0140] In the low-temperature side heat medium circuit 40 in the heater-heat absorption air heating mode, the low-temperature side heat medium, which has been heated by flowing through the cooling water passage 70a of the electric heater 70, absorbs heat in the chiller 20. As a result, the heat generated by the electric heater 70 can be effectively used to heat the blown air, thereby achieving heating of the vehicle interior.

[0141] Here, the control of the electric heater 70 in the heater heat absorption air heating mode is described. The control device 60 determines the permissible noise level of the compressor 11 based on the vehicle speed and with reference to the control map shown in Fig. 4. Specifically, the permissible noise level of the compressor 11 is determined to be high when the vehicle speed is higher than a predetermined value, and the permissible noise level of the compressor 11 is determined to be low when the vehicle speed is lower than the predetermined value. This is because the noise of the compressor 11 is easily masked by the driving noise when the vehicle speed is high.

[0142] When the allowable noise level of the compressor 11 is high, the controller 60 determines the upper limit speed of the compressor 11 to be a first upper limit speed Nclmt1, and when the allowable noise level of the compressor 11 is low, the controller 60 determines the upper limit speed of the compressor 11 to be a second upper limit speed Nclmt2 which is smaller than the first upper limit speed Nclmt1.

[0143] The controller 60 determines a target chiller inlet water temperature TWO based on the permissible noise level of the compressor 11 and a required heating capacity. Specifically, the target chiller inlet water temperature TWO is determined based on the permissible noise level of the compressor 11, the outside air temperature, and the target discharge temperature TAO with reference to the control map shown in Fig. 5 is shown.

[0144] Specifically, the higher the required heating capacity (e.g., the lower the outside air temperature, the higher the target discharge temperature TAO, the lower the intake air temperature of the indoor air conditioning unit 50, etc.), the higher the target chiller inlet water temperature TWO is set. Furthermore, the lower the required heating capacity (e.g., the higher the outside temperature, the lower the target discharge temperature TAO), the lower the target chiller inlet water temperature TWO is set.

[0145] Furthermore, the target chiller inlet water temperature TWO is set higher when the allowable noise level of the compressor 11 is low than that when the allowable noise level of the compressor 11 is high.

[0146] The controller 60 controls the power supplied to the electric heater 70 (in other words, the amount of heat generated by the electric heater 70) so that the chiller inlet water temperature TW approaches the target chiller inlet water temperature TWO. Specifically, the power supplied to the electric heater 70 (in other words, the amount of heat generated by the electric heater 70) is increased when the chiller inlet water temperature TW is lower than the target chiller inlet water temperature TWO, and the power supplied to the electric heater 70 (in other words, the amount of heat generated by the electric heater 70) is decreased when the chiller inlet water temperature TW is higher than the target chiller inlet water temperature TWO.

[0147] As a result, the amount of heat absorbed in the chiller 20 increases or decreases depending on the chiller inlet water temperature TW, as shown in Fig. 6, and the working amount of the compressor 11 (in other words, the rotational speed of the compressor 11) increases or decreases in a manner opposite to the amount of heat absorbed in the chiller 20, thereby achieving the desired heating capacity. Specifically, as the chiller inlet water temperature TW increases, the amount of heat absorbed in the chiller 20 increases, and the working amount of the compressor 11 (in other words, the rotational speed of the compressor 11) decreases.

[0148] As a result, the speed of the compressor 11 can be kept low when the allowable noise level of the compressor 11 is low, thus keeping the noise of the compressor 11 low. Furthermore, since the speed of the compressor 11 can be brought as close as possible to the allowable speed, the speed of the compressor 11 can be prevented from becoming too low. Therefore, it is possible to prevent the amount of heat absorbed by the chiller 20 from becoming too large, which leads to an increase in heat loss.

[0149] Next, an operation mode in which the refrigerant flows through the bypass passage 21c will be described. Examples of the operation mode in which the refrigerant flows through the bypass passage 21c include (d) a hot gas air heating mode, (e) a hot gas dehumidification air heating mode, and (f) a serial hot gas dehumidification air heating mode. (e) Hot gas air heating mode

[0150] The hot gas air heating mode is an operating mode for heating the vehicle interior. In the control program, the hot gas air heating mode is selected when the outside air temperature Tam is extremely low (less than -10°C in the present embodiment) or when it is determined that the heating performance of the ventilation air in the water / refrigerant heat exchanger 13 is insufficient in the outside air heat absorption air heating mode.

[0151] The control program determines that the ventilation air heating capacity is insufficient if the ventilation air temperature TAV is lower than the target discharge temperature TAO. The same applies to other operating modes.

[0152] Examples of the hot gas air heating mode include a simple hot gas air heating mode and a heating-heat absorption hot gas air heating mode. The simple hot gas air heating mode is an operation mode in which the air in the vehicle interior is heated without absorbing heat from the electric heater 70. The heating-heat absorption hot gas air heating mode is an operation mode in which heat is absorbed from the electric heater 70 to heat the vehicle interior. (e-1) Simple hot gas air heating mode

[0153] With the heat pump cycle 10 in the simple hot gas air heating mode, the controller 60 places the air heating expansion valve 14a in the fully closed state, the air cooling expansion valve 14b in the fully closed state, the cooling expansion valve 14c in the throttling state, and the bypass-side flow rate regulating valve 14d in the throttling state. The controller 60 opens the dehumidification on / off valve 22a and closes the air heating on / off valve 22b.

[0154] Therefore, the refrigerant discharged from the compressor 11 circulates in the heat pump circuit 10 in the simple hot gas air heating mode, as shown by solid arrows in Fig. 7, in this order through the first three-way node 12a, the water / refrigerant heat exchanger 13, the dehumidification passage 21a, the cooling expansion valve 14c in the throttling state, the chiller 20, the suction-side passage 21d, and the suction port of the compressor 11. At the same time, the refrigerant cycle is switched to a refrigerant cycle in which the refrigerant discharged from the compressor 11 circulates in this order through the first three-way node 12a, the bypass-side flow rate regulating valve 14d in the throttling state provided in the bypass passage 21c, the suction-side passage 21d, and the suction port of the compressor 11.

[0155] Further, the control device 60 controls the refrigerant discharge capacity of the compressor 11 in such a manner that the chiller-side refrigerant pressure Pc approaches a predetermined first target low pressure PSO1.

[0156] Controlling the chiller-side refrigerant pressure Pc according to the suction refrigerant pressure Ps to approach a constant pressure is effective for stabilizing a discharge flow rate Gr (the mass flow rate) of the compressor 11. Specifically, the density of the suction refrigerant becomes constant by generating a saturated gas-phase refrigerant with a constant pressure as the suction refrigerant pressure Ps. Therefore, the discharge flow rate Gr of the compressor 11 is easily stabilized at the same rotational speed when the suction refrigerant pressure Ps is controlled to approach a constant pressure.

[0157] The controller 60 controls the throttle opening of the bypass-side flow rate regulating valve 14d so that the discharge refrigerant pressure Pd approaches the target high pressure PDO.

[0158] The control device 60 also controls the throttle opening of the cooling expansion valve 14c in such a way that the superheat degree SH of the suction refrigerant approaches the reference superheat degree KSH.

[0159] In the high-temperature side heat medium circuit 30 in the simple hot gas air heating mode, the controller 60 operates the high-temperature side pump 31 as in the simple air cooling mode.

[0160] In the low-temperature side heat medium circuit 40 in the simple hot gas air heating mode, the controller 60 stops the low-temperature side pump 41.

[0161] When the interior air conditioning unit 50 is in the simple hot gas air heating mode, the controller 60 controls the opening degree of the air mix door 54 in a similar manner to the simple air conditioning mode. In the hot gas air heating mode, the opening of the air mix door 54 is often controlled so that approximately the entire volume of ventilation air blown from the interior blower 52 passes through the heater core 32.

[0162] The control device 60 controls the operation of the indoor air and the indoor and outdoor air switching device 53 to introduce indoor air into the air conditioning case 51. Furthermore, the control device 60 appropriately controls the operations of the other control target devices.

[0163] Therefore, in the heat pump circuit 10 in the simple hot gas air heating mode, the state of the refrigerant changes as shown in the Mollier diagram of Fig. 8 is shown.

[0164] First, the flow of the discharge refrigerant (point a8 in Fig. 8) discharged from the compressor 11 is branched at the first three-way node 12a. One of the refrigerant divided at the first three-way node 12a flows into the water / refrigerant heat exchanger 13 and dissipates heat to the high-temperature side heat medium (from point a8 to point b8 in Fig. 8). As a result, the high-temperature side heat medium is heated.

[0165] The refrigerant flowing out of the water / refrigerant heat exchanger 13 flows into the dehumidification passage 21a. The refrigerant flowing into the dehumidification passage 21a flows into the cooling expansion valve 14c and is expanded (from point b8 to point c8 in Fig. 8).

[0166] The refrigerant expanded at the cooling expansion valve 14c flows into the chiller 20. In the hot gas air heating mode, the chiller 20 does not exchange heat between the refrigerant and the low-temperature side heat medium because the low-temperature side pump 41 is stopped. The refrigerant flowing out of the chiller 20 flows into the other inlet port of the sixth three-way node 12f via the fourth three-way node 12d and the fifth three-way node 12e.

[0167] The other refrigerant branched at the first three-way node 12a flows into the bypass passage 21c. The refrigerant flowing into the bypass passage 21c is expanded when the flow rate is regulated by the bypass-side flow rate regulating valve 14d (from point a8 to point d8 in Fig. 8). The refrigerant, which is expanded at the bypass-side flow rate regulating valve 14d, flows into an inlet port of the sixth three-way node 12f.

[0168] The refrigerant flowing out of the chiller 20 and the refrigerant flowing out of the bypass-side flow rate regulating valve 14d are combined and mixed at the sixth three-way node 12f. The refrigerant flowing out of the sixth three-way node 12f is mixed while flowing through the suction-side passage 21d (point e8 in Fig. 8) and is sucked into the compressor 11.

[0169] As described above, in the heat pump cycle 10 in the hot gas air heating mode, refrigerants with different enthalpies, such as the low-enthalpy refrigerant flowing out of the chiller 20 (point c8 in Fig. 8), and the high-enthalpy refrigerant flowing out of the bypass passage 21c (point d8 in Fig. 8), mixed and sucked into the compressor 11.

[0170] Therefore, the cooling expansion valve 14c in the heat pump cycle 10 serves as the heating unit side expansion unit in the hot gas air heating mode.

[0171] In the high-temperature side heat medium circuit 30 in the hot gas air heating mode, the high-temperature side heat medium heated by the water / refrigerant heat exchanger 13 flows into the heater core 32 as in the simple air cooling mode.

[0172] As in the outside air heat absorption air heating mode, in the simple hot gas air heating mode, the interior air conditioning unit 50 blows temperature-controlled ventilation air into the vehicle interior to achieve heating of the vehicle interior.

[0173] Here, the simple hot gas air heating mode is an operation mode executed when the outside air temperature Tam is extremely low. For this reason, when the refrigerant flowing out of the water / refrigerant heat exchanger 13 flows into the outdoor heat exchanger 15, the refrigerant in the outdoor heat exchanger 15 can dissipate heat to the outside air. When the refrigerant in the outdoor heat exchanger 15 dissipates heat to the outside air, the amount of heat that the refrigerant in the water / refrigerant heat exchanger 13 dissipates to the ventilation air decreases, and the heating performance of the ventilation air decreases accordingly.

[0174] In the simple hot gas air heating mode of the present embodiment, it is possible to prevent the refrigerant from dissipating heat to the outside air in the outdoor heat exchanger 15 because the refrigerant cycle is switched to the refrigerant cycle that does not allow the refrigerant flowing out of the water / refrigerant heat exchanger 13 to flow into the outdoor heat exchanger 15.

[0175] In the simple hot gas air heating mode of the present embodiment, the throttle opening of the cooling expansion valve 14c is controlled in such a way that the superheat degree SH of the suction refrigerant approaches the reference superheat degree KSH. As a result, the state of the suction refrigerant (point e8 in Fig. 8) the gas-phase refrigerant having the degree of superheat even if the amount of heat dissipated in the water / refrigerant heat exchanger 13 from the discharge refrigerant to the high-temperature side heat medium is increased by increasing the refrigerant discharge capacity of the compressor 11.

[0176] Therefore, in the simple hot gas air heating mode, the heat generated by the working amount of the compressor 11 can be effectively used to heat the ventilation air even when the outside air temperature Tam is extremely low, and the air in the vehicle interior can be heated.

[0177] (e-2) Heating-Heat-Absorbing Hot-Gas Air Heating Mode. In the heating-heat-absorbing hot-gas air heating mode, compared to the simple hot-gas air heating mode, the controller 60 operates the low-temperature-side pump 41 of the low-temperature-side heat medium circuit 40 to exhibit the predetermined reference pumping capacity. Therefore, in the heating-heat-absorbing hot-gas air heating mode, the refrigerant flowing into the chiller 20 in the heat pump cycle 10 absorbs heat from the low-temperature-side heat medium. Due to this, the low-temperature-side heat medium is cooled. The other operations are similar to those in the simple hot-gas air heating mode.

[0178] Therefore, in the heating-heat-absorbing hot-gas air-heating mode, the heat generated by the working amount of the compressor 11 can be effectively used to heat the ventilation air, and the air in the vehicle interior can be heated as in the simple hot-gas air-heating mode. Furthermore, the low-temperature side heat medium, which has been heated by flowing through the cooling water passage 70a of the electric heater 70, absorbs heat in the low-temperature side heat medium circuit 40 in the heating-heat-absorbing hot-gas air-heating mode in the chiller 20. As a result, the heat generated by the electric heater 70 can be effectively used to heat the blown air, thereby achieving heating of the vehicle interior.

[0179] In the heater heat absorption hot gas heating mode, the controller 60 operates the electric heater 70 in the same manner as in the heater heat absorption air heating mode. As a result, the rotational speed of the compressor 11 can be kept low in a manner similar to the heater heat absorption air heating mode to keep the noise of the compressor 11 low when the allowable noise level of the compressor 11 is low. Furthermore, since the rotational speed of the compressor 11 can be brought as close as possible to the allowable speed, the rotational speed of the compressor 11 can be prevented from becoming too low. Therefore, it is possible to prevent the amount of heat absorbed by the chiller 20 from becoming too large, which leads to an increase in heat loss. (f) Hot gas dehumidification air heating mode

[0180] The hot gas dehumidification air heating mode is an operating mode in which the air in the vehicle interior is dehumidified and heated. In the control program, the hot gas dehumidification air heating mode is selected when the outside air temperature Tam is within a predetermined low-to-medium temperature range (equal to or higher than 0°C and lower than 10°C in the present embodiment).

[0181] When the heat pump cycle 10 is in the hot gas dehumidification air heating mode, the controller 60 places the air heating expansion valve 14a in the fully closed state, the air cooling expansion valve 14b in the throttling state, the cooling expansion valve 14c in the throttling state, and the bypass-side flow rate regulating valve 14d in the throttling state. The controller 60 opens the dehumidification on / off valve 22a and closes the air heating on / off valve 22b.

[0182] Therefore, the refrigerant discharged from the compressor 11 circulates in the heat pump cycle 10 in the hot-gas dehumidification air heating mode in a manner similar to the simple hot-gas air heating mode. At the same time, the refrigerant circuit is switched to a refrigerant circuit in which the refrigerant discharged from the compressor 11 circulates, in this order, through the first three-way node 12a, the water-refrigerant heat exchanger 13, the dehumidification passage 21a, the air-cooling expansion valve 14b in the throttling state, the indoor evaporator 18, the suction-side passage 21d, and the suction port of the compressor 11. That is, the refrigerant circuit is switched to a refrigerant circuit in which the indoor evaporator 18 and the chiller 20 are connected in parallel to the refrigerant flow.

[0183] Furthermore, the controller 60 controls the refrigerant discharge capacity of the compressor 11 such that the intake refrigerant pressure Ps approaches a predetermined second target low pressure PSO2. The second target low pressure PSO2 is determined such that the refrigerant evaporation temperature in the indoor evaporator 18 is a temperature at which the ventilation air can be dehumidified without causing icing on the indoor evaporator 18.

[0184] In addition, the controller 60 controls the throttle opening of the bypass-side flow rate regulating valve 14d as in the hot gas air heating mode in such a manner that the discharge refrigerant pressure Pd approaches the target high pressure PDO.

[0185] The controller 60 controls the throttle opening of the air cooling expansion valve 14b to a predetermined throttle opening for the hot gas dehumidification air heating mode.

[0186] The control device 60 also controls the throttle opening of the expansion valve 14c in such a way that the superheat degree SH of the suction refrigerant approaches the reference superheat degree KSA.

[0187] In the high-temperature side heat medium circuit 30 in the hot gas dehumidification air heating mode, the controller 60 operates the high-temperature side pump 31 as in the air cooling mode.

[0188] In the low-temperature side heat medium circuit 40 in the hot gas dehumidification air heating mode, the controller 60 stops the low-temperature side pump 41.

[0189] When the indoor air conditioning unit 50 is in the hot gas dehumidification air heating mode, the controller 60 controls the ventilation power of the indoor fan 52 and the opening of the air mix door 54 as in the air cooling mode. Furthermore, the controller 60 appropriately controls the operations of the other control target devices.

[0190] Therefore, in the heat pump cycle 10 in the hot gas dehumidification air heating mode, the state of the refrigerant changes as follows.

[0191] The flow of the discharge refrigerant discharged from the compressor 11 is branched at the first three-way node 12a. One of the refrigerants split at the first three-way node 12a flows into the water / refrigerant heat exchanger 13 and transfers heat to the high-temperature side heat medium. As a result, the high-temperature side heat medium is heated.

[0192] The refrigerant flowing out of the water / refrigerant heat exchanger 13 flows into the dehumidification passage 21a. The flow of the refrigerant flowing into the dehumidification passage 21a is branched at the four-way node 12x. One of the refrigerant branched at the four-way node 12x flows into the air-cooling expansion valve 14b and is expanded.

[0193] The refrigerant expanded at the air-cooling expansion valve 14b flows into the indoor evaporator 18. The refrigerant flowing into the indoor evaporator 18 exchanges heat with the ventilation air supplied by the indoor fan 52 and evaporates. As a result, the ventilation air is cooled and dehumidified. The refrigerant flowing out of the indoor evaporator 18 flows into an inlet port of the fifth three-way node 12e via the second check valve 16b.

[0194] The other refrigerant branched at the four-way node 12x flows into the cooling expansion valve 14c and is expanded. The refrigerant expanded at the cooling expansion valve 14c flows into the chiller 20. In the hot gas dehumidification air heating mode, the chiller 20 does not exchange heat between the refrigerant and the low-temperature side heat medium because the low-temperature side pump 41 is stopped. The refrigerant flowing out of the chiller 20 flows into the other inlet port of the fifth three-way node 12e.

[0195] At the fifth three-way node 12e, the flow of refrigerant flowing out of the indoor evaporator 18 and the flow of refrigerant flowing out of the chiller 20 are combined. The refrigerant flowing out of the fifth three-way node 12e flows into the other inlet port of the sixth three-way node 12f.

[0196] The other refrigerant branched at the first three-way node 12a flows into the bypass passage 21c. The refrigerant flowing into the bypass passage 21c is expanded when the flow rate is regulated by the bypass-side flow rate regulating valve 14d, as in the hot-gas air heating mode. The refrigerant expanded at the bypass-side flow rate regulating valve 14d flows into an inflow port of the sixth three-way node 12f.

[0197] The refrigerant flowing out of the fifth three-way node 12e and the refrigerant flowing out of the bypass-side flow rate regulating valve 14d are combined and mixed at the sixth three-way node 12f. The refrigerant flowing out of the sixth three-way node 12f is mixed while flowing through the suction-side passage 21d and is then sucked into the compressor 11.

[0198] As described above, in the heat pump cycle 10 in the hot gas dehumidification air heating mode, the refrigerant cycle is switched to a refrigerant cycle in which refrigerants having different enthalpies, such as the low-enthalpy refrigerant flowing out of the chiller 20, the high-enthalpy refrigerant flowing out of the bypass passage 21c, and the refrigerant flowing out of the indoor evaporator 18, are mixed and sucked into the compressor 11.

[0199] Therefore, the air cooling expansion valve 14b and the cooling expansion valve 14c in the heat pump cycle 10 serve as the heating unit side expansion unit in the hot gas dehumidification air heating mode.

[0200] In the high-temperature side heat medium circuit 30 in the hot-gas dehumidification-air heating mode, the high-temperature side heat medium heated by the water / refrigerant heat exchanger 13 flows into the heater core 32 as in the air-cooling mode. In the interior air conditioning unit 50 in the hot-gas dehumidification-air heating mode, the ventilation air at a regulated temperature is blown into the vehicle interior, so that the air in the vehicle interior is dehumidified and heated as in the serial dehumidification-air heating mode.

[0201] Here, the hot gas dehumidification air heating mode is an operation mode in which the ventilation air is cooled and dehumidified, and the dehumidified ventilation air is reheated to a desired temperature and blown into the vehicle interior. Therefore, in the hot gas dehumidification air heating mode, it is necessary to regulate the working amount of the compressor 11 in such a way that the temperature of the ventilation air can be reheated to a desired temperature by the heating unit without causing icing on the interior evaporator 18.

[0202] In the hot gas dehumidification air heating mode of the present embodiments, the refrigerant with a comparatively high enthalpy flows into the sixth three-way node 12f via the bypass passage 21c. Even if the refrigerant discharge capacity of the compressor 11 is increased, it is possible to prevent the suction refrigerant pressure Ps from decreasing. As a result, the amount of heat dissipated from the discharge refrigerant to the high-temperature side heat medium in the water-refrigerant heat exchanger 13 can be increased without causing frost formation in the indoor evaporator 18.

[0203] Therefore, the ventilation air can be heated in the hot gas dehumidification air heating mode with a higher heating capacity than in the serial dehumidification air heating mode. (g) Serial hot gas dehumidification air heating mode

[0204] The serial hot gas dehumidification and air heating mode is an operating mode in which the air in the vehicle interior is dehumidified and heated. In the control program, the serial hot gas dehumidification and air heating mode is selected when it is determined that the heating performance of the ventilation air in the water / refrigerant heat exchanger 13 is insufficient in the serial dehumidification and air heating mode.

[0205] When the heat pump cycle 10 is in the serial hot gas dehumidification-air heating mode, the controller 60 places the air heating expansion valve 14a in the throttling state, the air cooling expansion valve 14b in the throttling state, the cooling expansion valve 14c in the throttling state, and the bypass-side flow rate regulating valve 14d in the throttling state. Furthermore, the controller 60 closes the dehumidification on / off valve 22a and also closes the air heating on / off valve 22b.

[0206] Therefore, the refrigerant discharged from the compressor 11 circulates in the heat pump cycle 10 in the serial hot gas dehumidification-air heating mode in a manner similar to that in the serial cooling-dehumidification-air heating mode. At the same time, the refrigerant circuit is switched to a refrigerant circuit in which the refrigerant discharged from the compressor 11 circulates, in this order, through the first three-way node 12a, the bypass-side flow rate regulating valve 14d in the throttle state provided in the bypass passage 21c, the sixth three-way node 12f, the suction-side passage 21d, and the suction port of the compressor 11.

[0207] Further, the controller 60 controls the refrigerant discharge capacity of the compressor 11 as in the hot gas dehumidification air heating mode in such a manner that the suction refrigerant pressure Ps approaches the predetermined second target low pressure PSO2.

[0208] In addition, the controller 60 controls the throttle opening of the bypass-side flow rate regulating valve 14d as in the hot gas air heating mode in such a manner that the discharge refrigerant pressure Pd approaches the target high pressure PDO.

[0209] The controller 60 controls the throttle opening of the air heating expansion valve 14a and the throttle opening of the air cooling expansion valve 14b to a predetermined throttle opening for the serial hot gas dehumidification air heating mode.

[0210] The controller 60 also controls the throttle opening of the cooling expansion valve 14c as in the hot gas dehumidification air heating mode in such a manner that the superheat degree SH of the suction refrigerant approaches the reference superheat degree KSH.

[0211] In the high-temperature side heat medium circuit 30 in the hot gas dehumidification air heating mode, the controller 60 operates the high-temperature side pump 31 as in the air cooling mode.

[0212] In the low-temperature side heat medium circuit 40 in the hot gas dehumidification air heating mode, the controller 60 stops the low-temperature side pump 41.

[0213] When the indoor air conditioning unit 50 is in the hot gas dehumidification air heating mode, the controller 60 controls the ventilation capacity of the indoor fan 52 and the opening of the air mix door 54 as in the air cooling mode. Furthermore, the controller 60 appropriately controls the operations of the other control target devices.

[0214] Therefore, in the heat pump circuit 10, the serial hot gas dehumidification air heating mode, the state of the refrigerant changes as follows.

[0215] The flow of the discharge refrigerant discharged from the compressor 11 is branched at the first three-way node 12a. One of the refrigerants split at the first three-way node 12a flows into the water / refrigerant heat exchanger 13 and transfers heat to the high-temperature side heat medium. As a result, the high-temperature side heat medium is heated.

[0216] The refrigerant flowing out of the water / refrigerant heat exchanger 13 flows into the air-heating expansion valve 14a and is expanded. The refrigerant expanded at the air-heating expansion valve 14a flows into the outdoor heat exchanger 15. The refrigerant flowing into the outdoor heat exchanger 15 exchanges heat with the outside air and reduces its enthalpy.

[0217] The flow of refrigerant flowing out of the outdoor heat exchanger 15 is branched at the four-way node 12x. One of the refrigerants branched at the four-way node 12x flows into the air-cooling expansion valve 14b and is expanded.

[0218] The refrigerant expanded by the air-cooling expansion valve 14b flows into the indoor evaporator 18, exchanges heat with the ventilation air supplied by the indoor fan 52, and evaporates as in the hot-gas dehumidification / air heating mode. As a result, the ventilation air is cooled and dehumidified. The refrigerant flowing out of the indoor evaporator 18 flows into an inlet port of the fifth three-way node 12e via the second check valve 16b.

[0219] The other refrigerant branched at the four-way node 12x flows into the cooling expansion valve 14c and is expanded, as in the hot gas air heating mode. The refrigerant expanded at the cooling expansion valve 14c flows into the chiller 20. The refrigerant flowing out of the chiller 20 flows into the other inlet port of the fifth three-way node 12e.

[0220] The flow of refrigerant flowing out of the indoor evaporator 18 and the flow of refrigerant flowing out of the chiller 20 are combined at the fifth three-way node 12e, as in the hot-gas air heating mode. The refrigerant flowing out of the fifth three-way node 12e flows into the other inlet port of the sixth three-way node 12f.

[0221] The other refrigerant branched at the first three-way node 12a flows into the bypass passage 21c. The refrigerant flowing into the bypass passage 21c is expanded as in the hot-gas air heating mode when the flow rate is regulated by the bypass-side flow rate regulating valve 14d. The refrigerant expanded at the bypass-side flow rate regulating valve 14d flows into an inflow port of the sixth three-way node 12f.

[0222] The refrigerant flowing out of the fifth three-way node 12e and the refrigerant flowing out of the bypass-side flow rate regulating valve 14d are combined and mixed at the sixth three-way node 12f, as in the hot gas dehumidification air heating mode. The refrigerant flowing out of the sixth three-way node 12f is mixed while flowing through the suction-side passage 21d and is sucked into the compressor 11.

[0223] As described above, in the heat pump cycle 10 in the serial hot gas dehumidification air heating mode, the refrigerant cycle is switched to a refrigerant cycle in which refrigerants having different enthalpies, such as the low-enthalpy refrigerant flowing out of the chiller 20, the high-enthalpy refrigerant flowing out of the bypass passage 21c, and the refrigerant flowing out of the indoor evaporator 18, are mixed and sucked into the compressor 11.

[0224] Therefore, in the heat pump cycle 10 in the serial hot gas dehumidification air heating mode, the air heating expansion valve 14a, the air cooling expansion valve 14b and the cooling expansion valve 14c serve as the heating unit side expansion unit.

[0225] In the high-temperature side heat medium circuit 30 in the serial hot gas dehumidification air heating mode, the high-temperature side heat medium heated by the water / refrigerant heat exchanger 13 flows into the heater core 32 as in the air cooling mode.

[0226] In the interior air conditioning unit 50 in the serial hot gas dehumidification-air heating mode, the ventilation air is blown into the vehicle interior at a regulated temperature as in the serial dehumidification-air heating mode, so that the air in the vehicle interior is dehumidified and heated.

[0227] In the serial hot gas dehumidification air heating mode, as in the hot gas dehumidification air heating mode, it is necessary to regulate the refrigerant discharge capacity of the compressor 11 in such a way that the heating unit can reheat the ventilation air to a desired temperature without causing icing on the indoor evaporator 18.

[0228] In the serial hot gas dehumidification air heating mode of the present embodiment, the refrigerant having a comparatively high enthalpy flows into the sixth three-way node 12f via the bypass passage 21c. Therefore, as in the serial hot gas dehumidification air heating mode, it is possible to increase the amount of heat dissipated from the discharge refrigerant to the ventilation air in the water-refrigerant heat exchanger 13 without causing icing on the indoor evaporator 18 even if the refrigerant discharge capacity of the compressor 11 is increased.

[0229] As a result, the ventilation air can be heated in the serial hot gas dehumidification air heating mode with a higher heating capacity than in the serial dehumidification air heating mode.

[0230] As described above, according to the vehicle air conditioner 1 of the present disclosure, comfortable air conditioning in the vehicle interior can be implemented by switching the operation mode.

[0231] In this embodiment, the controller 60 lowers the upper limit speed of the compressor 11 in the heater heat absorption air heating mode and the heater heat absorption hot gas heating mode as the acceptable noise level for the compressor 11 decreases, and increases the amount of heat absorbed in the chiller 20 as the acceptable noise level for the compressor 11 decreases.

[0232] As a result, the amount of heat absorbed by the chiller 20 increases as the allowable noise level of the compressor 11 decreases, so the desired heating capacity can be ensured even if the working amount of the compressor 11 (in other words, the rotational speed of the compressor 11) is reduced. Therefore, it is possible to suppress the noise of the compressor while ensuring the necessary heating capacity.

[0233] Specifically, in the heating heat absorption hot gas air heating mode, refrigerants with different enthalpies, such as a low enthalpy refrigerant flowing out of the chiller 20 and a high enthalpy refrigerant flowing out of the bypass passage 21c, are mixed and sucked into the compressor to make it possible to effectively utilize the heat generated by the work amount of the compressor for heating while suppressing compressor noise and ensuring the necessary heating capability.

[0234] In this embodiment, the controller 60 increases the amount of heat absorbed in the chiller 20 so that the heating capacity approaches the target heating capacity as the allowable noise level of the compressor 11 is reduced. This allows the amount of heat absorbed in the chiller 20 to be appropriately controlled, thereby suppressing an increase in heat loss caused by an excessive increase in the amount of heat absorbed in the chiller 20.

[0235] In this embodiment, the controller 60 increases the amount of heat generated by the electric heater 70 as the allowable noise level of the compressor 11 decreases. This allows the amount of heat absorbed by the chiller 20 to be increased in accordance with a decrease in the allowable noise level of the compressor 11.

[0236] In this embodiment, the controller 60 reduces the upper limit speed of the compressor 11 as the vehicle speed decreases. This allows the speed of the compressor 11 to be reduced in accordance with a reduction in the permissible noise level of the compressor 11. (Second embodiment)

[0237] In the present embodiment, which is shown in Fig. As shown in Fig. 9, an indoor condenser 131 is provided in place of the water / refrigerant heat exchanger 13 and the high-temperature side heat medium circuit 30 in the heat pump cycle 10 of the first embodiment. In this embodiment, an accumulator 23 is added to the heat pump cycle 10 in the vehicle air conditioner 1 of the first embodiment.

[0238] In the heat pump cycle 10, an inflow port side of a refrigerant passage in the indoor condenser 131 is connected to an outflow port of the first three-way node 12a. The indoor condenser 131 is provided in the air conditioning case 51 of the indoor air conditioning unit 50 in a manner similar to the heater core 32 described in the first embodiment.

[0239] The indoor condenser 131 is a heating heat exchanger that exchanges heat between the high-pressure refrigerant discharged from the compressor 11 and the ventilation air passing through the indoor evaporator 18 to heat the ventilation air. Therefore, the indoor condenser 131 is a heating unit that heats the blown air as an object to be heated by using one of the discharge refrigerants branched at the first three-way node 12a as a heat source.

[0240] The accumulator 23 is provided on the outlet side of the sixth three-way node 12f in the suction-side passage 21b. The accumulator 23 is a low-pressure gas-liquid separation unit that separates the refrigerant flowing through the suction-side passage 21d into a gas and a liquid and stores the separated liquid-phase refrigerant as excess refrigerant in the cycle. The inlet port side of the compressor 11 is connected to a gas-phase refrigerant outlet of the accumulator 23. The suction refrigerant temperature sensor 62f is provided in the refrigerant flow of the gas-phase refrigerant outlet port of the accumulator 23 on the downstream side.

[0241] The remaining configurations and operations are similar to those of the first embodiment. Therefore, effects similar to those of the first embodiment can be achieved. (Third embodiment)

[0242] In this embodiment, as in Fig. 10, in the heat pump circuit 10, the air heating expansion valve 14a and the outdoor heat exchanger 15 are arranged in parallel with the cooling expansion valve 14c and the chiller 20.

[0243] In this embodiment, the desired heating capacity is achieved by the sum of the working amount of the compressor 11, the amount of heat absorbed by the outdoor heat exchanger 15, and the amount of heat generated by the electric heater 70.

[0244] The controller 60 controls the amount of heat absorbed by the chiller 20 (i.e., the amount of heat generated by the electric heater 70) in a manner similar to the heater heat absorption air heating mode of the first and second embodiments according to the allowable noise level of the compressor 11.

[0245] As a result, in a similar manner to the first and second embodiments, the rotational speed of the compressor 11 can be kept low to keep the noise of the compressor 11 low when the allowable noise level of the compressor 11 is low.

[0246] In this embodiment, the desired heating capacity is achieved by the sum of the working amount of the compressor 11, the amount of heat absorbed by the outdoor heat exchanger 15, and the amount of heat generated by the electric heater 70. Therefore, as the amount of heat generated by the electric heater 70 increases, the speed of the compressor 11 decreases and the amount of heat absorbed by the outdoor heat exchanger 15 decreases. If the amount of heat absorbed by the outdoor heat exchanger 15 becomes too small, the system efficiency decreases.

[0247] In this regard, in the present embodiment, as the allowable noise level of the compressor 11 decreases, the amount of heat absorbed in the chiller 20 (i.e., the amount of heat generated by the electric heater 70) is increased, so that the heating capacity of the heater core 32 or the water-refrigerant heat exchanger 13 (in the configuration of the second embodiment described above, the indoor condenser 131) approaches the target heating capacity, allowing the compressor 11 to operate near its upper limit speed. Therefore, it is possible to suppress a decrease in system efficiency caused by an excessively small heat absorption amount in the outdoor heat exchanger 15. (Fourth embodiment)

[0248] In this embodiment, as in Fig. As shown in Fig. 11, a radiator 42 is provided in series with the electric heater 70 in the low-temperature side heat medium circuit 40. The radiator 42 is an outside air heat exchanger that exchanges heat between the low-temperature heat medium cooled by the chiller 20 and outside air blown by an outside air fan (not shown).

[0249] A radiator bypass passage 43 and a bypass on / off valve 44 are arranged in the low-temperature-side heat medium circuit 40. The radiator bypass passage 43 is a flow path through which the low-temperature-side heat medium flows while bypassing the radiator 42. The bypass on / off valve 44 is an on / off valve that opens and closes the radiator bypass passage 43. The bypass on / off valve 44 is an electromagnetic valve whose opening and closing operation is controlled by a control voltage output from the controller 60.

[0250] When the temperature of the low-temperature heat medium is higher than the outside air temperature, the radiator 43 cannot absorb heat from the low-temperature heat medium, so the bypass on / off valve 44 is opened to stop the flow of the low-temperature heat medium to the radiator 42.

[0251] In this embodiment, the desired heating capacity is achieved by the sum of the amount of work of the compressor 11, the amount of heat absorbed by the radiator 42, and the amount of heat generated by the electric heater 70.

[0252] The controller 60 controls the amount of heat absorbed by the chiller 20 (i.e., the amount of heat generated by the electric heater 70) in a manner similar to the heater heat absorption air heating mode of the first and second embodiments according to the allowable noise level of the compressor 11.

[0253] As a result, the rotational speed of the compressor 11 can be kept low in a similar manner to the first and second embodiments to keep the noise of the compressor 11 low when the allowable noise level of the compressor 11 is low.

[0254] In this embodiment, the desired heating capacity is achieved by the sum of the working amount of the compressor 11, the amount of heat absorbed by the radiator 42, and the amount of heat generated by the electric heater 70. Therefore, as the amount of heat generated by the electric heater 70 increases, the speed of the compressor 11 decreases and the amount of heat absorbed by the radiator 42 decreases. If the amount of heat absorbed by the radiator 42 becomes too small, the system efficiency decreases.

[0255] In this regard, as the allowable noise level of the compressor 11 decreases, the amount of heat absorbed in the chiller 20 (i.e., the amount of heat generated by the electric heater 70) increases, so that the heating capacity of the heater core 32 or the water-refrigerant heat exchanger 13 (in the configuration of the second embodiment described above, the indoor condenser 131) approaches the target heating capacity, allowing the compressor 11 to operate near its upper limit speed. Therefore, it is possible to suppress a reduction in system efficiency caused by an excessively small amount of heat absorption in the radiator 42. (Fifth embodiment)

[0256] In the above first to fourth embodiments, the amount of heat absorbed in the chiller 20 is controlled by controlling the heat generation amount of the electric heater 70. In this embodiment, the amount of heat absorbed in the chiller 20 is controlled by controlling the superheat degree SH of the refrigerant that has exchanged heat in the chiller 20.

[0257] Specifically, the controller 60 decreases a target superheat degree SHO of the superheat degree SH of the refrigerant that has undergone heat exchange in the chiller 20 as the allowable noise level of the compressor 11 decreases. The controller 60 controls the throttle opening degree of the cooling expansion valve 14c so that the superheat degree SH of the refrigerant that has undergone heat exchange in the chiller 20 approaches the target superheat degree SHO. That is, when the superheat degree SH of the refrigerant that has undergone heat exchange in the chiller 20 is greater than the target superheat degree SHO, the throttle opening of the cooling expansion valve 14c is increased.

[0258] As a result, the flow rate of the refrigerant passing through the cooling expansion valve 14c increases, so that the flow rate of the refrigerant flowing through the chiller 20 also increases, and the amount of heat absorbed in the chiller 20 increases. That is, as in Fig. As shown in FIG. 12, the amount of heat absorbed by the chiller 20 increases as the target superheat degree SHO of the superheat degree SH of the refrigerant that has undergone heat exchange in the chiller 20 decreases. As a result, in a manner similar to the first embodiment, the rotational speed of the compressor 11 can be kept low to keep the noise of the compressor 11 low when the allowable noise level of the compressor 11 is low.

[0259] In this embodiment, the controller 60 reduces the superheat degree SH of the refrigerant that has performed heat exchange in the chiller 20 in accordance with a reduction in the allowable noise level of the compressor 11. This makes it possible to quickly increase the amount of heat absorbed by the chiller 20 in accordance with a reduction in the allowable noise level of the compressor 11.

[0260] The present disclosure is not limited to the above-described embodiments and may be variously modified as follows without departing from the gist of the present disclosure.

[0261] In the first embodiment described above, the permissible noise level of the compressor 11 is determined based on the vehicle speed to have two levels, high and low. The permissible noise level of the compressor 11 may also be determined continuously based on the vehicle speed.

[0262] That is, the permissible noise level of the compressor 11 can be continuously reduced as the vehicle speed decreases.

[0263] Furthermore, in the above-described embodiment, the upper limit speed of the compressor 11 is determined based on the allowable noise level of the compressor 11 in two stages, the first upper limit speed Nclmt1 and the second upper limit speed Nclmt2. However, the upper limit speed of the compressor 11 may be determined continuously based on the allowable noise level of the compressor 11.

[0264] That is, the upper limit speed of the compressor 11 can be continuously reduced as the allowable noise level of the compressor 11 decreases.

[0265] The configuration of the heat pump cycle device according to the present disclosure is not limited to the configurations disclosed in the above embodiments.

[0266] In the first and second embodiments described above, the other inflow port of the sixth three-way node 12f is connected to the outlet side of the fifth three-way node 12e, and the outlet port of the sixth three-way node 12f is connected to the suction side of the compressor 11. However, the other inflow port of the sixth three-way node 12f may be connected to the outlet side of the cooling expansion valve 14c, and the outlet port of the sixth three-way node 12f may be connected to the inlet side of the chiller 20.

[0267] In the second embodiment described above, the refrigerant that has flowed through the bypass passage 21c flows into the accumulator 23 via the sixth three-way node 12f. However, the refrigerant that has flowed through the bypass passage 21c may also flow directly into the accumulator 23 without passing through the sixth three-way node 12f.

[0268] In the embodiments described above, the heating element arranged in the low-temperature side heat medium circuit 40 is the electric heater 70, but this is not limited to this, and the heating element arranged in the low-temperature side heat medium circuit 40 may be various heating elements whose heat generation amount can be controlled by a control signal output from the controller 60.

[0269] In the above embodiments, the example in which the second check valve 16b is used has been described, but an evaporation pressure regulating valve may be used instead of the second check valve 16b. The evaporation pressure regulating valve is a variable throttling mechanism that maintains a refrigerant evaporation temperature in the indoor evaporator 18 at a predetermined temperature (for example, a temperature at which the indoor evaporator 18 can be suppressed) or higher.

[0270] As the evaporation pressure regulating valve, a variable throttle mechanism having a mechanical mechanism that increases a valve opening as the refrigerant pressure on the refrigerant outlet port side of the indoor evaporator 18 increases can be used. As the evaporation pressure regulating valve, a variable throttle mechanism having an electrical mechanism similar to that of the air-heating expansion valve 14a, or the like, can be used.

[0271] The control sensor group connected to the input side of the controller 60 is not limited to the sensing units disclosed in the above embodiments. Various sensing units can be added as necessary.

[0272] In the above embodiment, the example in which R1234yf is used as the refrigerant of the heat pump cycle 10 was described, but the present disclosure is not limited thereto. For example, R134a, R600a, R410A, R404A, R32, R407C, and the like can be used. Alternatively, a mixed refrigerant or the like in which several types of these refrigerants are mixed together can be used. Furthermore, carbon dioxide can be used as the refrigerant to form a supercritical refrigeration cycle in which the high-pressure side refrigerant pressure is equal to or higher than the critical pressure of the refrigerant.

[0273] The example of using an aqueous ethylene glycol solution as the low-temperature side heat medium and the high-temperature side heat medium of the above-described embodiments has been described, but it is not limited thereto. For example, dimethylpolysiloxane, a solution containing a nanofluid, or the like, an antifreeze, an aqueous liquid refrigerant containing alcohol, or the like, a liquid medium containing oil, or the like, and the like can be used as the high-temperature side heat medium and the low-temperature side heat medium.

[0274] The control mode of the heat pump cycle device according to the present disclosure is not limited to the control modes disclosed in the above embodiments.

[0275] In the above-described embodiment, the vehicle air conditioner 1 capable of performing various operating modes has been described. However, the heat pump cycle device according to the present disclosure is not necessarily capable of performing all of the above-described operating modes.

[0276] The heat pump cycle device according to the present disclosure can achieve effects similar to those of the above embodiments as long as the heat pump cycle device can execute at least one of the heating-heat absorption air heating mode and the heating-heat absorption hot gas air heating mode. That is, even in the heat pump cycle device in which refrigerants with different enthalpies are mixed and drawn into the compressor, the compressor 11 can be protected without deteriorating productivity. Furthermore, other operation modes can be executed.

[0277] Moreover, the control mode of the controller 60 in the heating heat absorption air heating mode is not limited to the examples disclosed in the above embodiments.

[0278] For example, in the above-described embodiment, the controller 60 determines the allowable noise level of the compressor 11 based on the vehicle speed. However, the controller 60 may also determine the allowable noise level of the compressor 11 based on the air volume (in other words, the rotational speed) of the interior blower 52 or the air volume (in other words, the rotational speed) of an outside air fan, not shown. This is because the noise of the compressor 11 is easily masked by the operating noise and blowing noise of the interior blower 52 and the outside air fan when the air volume of the interior blower 52 or the outside air fan is large. This also applies to the heating heat absorption hot gas air heating mode.

[0279] In the present embodiment, the controller 60 reduces the upper limit speed of the compressor 11 as the air flow rate of the indoor fan 52 decreases. This makes it possible to reduce the speed of the compressor 11 in accordance with a reduction in the allowable noise level of the compressor 11.

[0280] In this embodiment, the controller 60 reduces the upper limit speed of the compressor 11 according to a decrease in the blowing amount of the outside air fan that blows outside air. This makes it possible to reduce the speed of the compressor 11 according to a decrease in the allowable noise level of the compressor 11.

[0281] The present disclosure has been described according to examples, but it is understood that the present disclosure is not limited to the examples and structures. The present disclosure encompasses various modifications and variations within the scope of equivalence. Furthermore, various combinations and modes, as well as other combinations and modes including only one element, multiple elements, or fewer elements, are also within the scope and spirit of the present disclosure.

[0282] The vehicle heat pump cycle device disclosed in this specification has the following features. (Item 1)

[0283] A vehicle heat pump cycle device comprising: a compressor (11) configured to suck in, compress, and discharge a refrigerant; a heating unit (13, 131) configured to heat an object to be heated by using a refrigerant discharged from the compressor as a heat source; an expansion unit (14c) configured to expand a refrigerant flowing out of the heating unit; and a heat absorption unit (20) configured to cause a refrigerant expanded by the expansion unit to absorb heat generated by a heat generation unit (70), wherein the heat absorption unit is configured to increase a heat absorption amount in accordance with a reduction in an allowable noise level of the compressor. (Item 2)

[0284] A vehicle heat pump cycle device comprising: a compressor (11) configured to suck in, compress, and discharge a refrigerant; a heating unit (13, 131) configured to heat an object to be heated by using a refrigerant discharged from the compressor as a heat source; an expansion unit (14c) configured to expand a refrigerant flowing out of the heating unit; a heat absorption unit (20) configured to cause a refrigerant expanded by the expansion unit to absorb heat generated by a heat generation unit (70);and an upper limit speed determining unit (60a) configured to determine an upper limit speed of the compressor, wherein the upper limit speed determining unit is configured to lower the upper limit speed according to a reduction in a permissible noise level of the compressor, and the heat absorption unit is configured to increase a heat absorption amount according to a reduction in the permissible noise level of the compressor; (Item 3)

[0285] The vehicle heat pump cycle device according to item 2, further comprising: a target heating capacity determining unit (60d) configured to determine a target heating capacity of the heating unit, wherein the heat absorption unit is configured to increase the heat absorption amount so that the heating capacity of the heating unit approaches the target heating capacity according to a reduction in the allowable noise level of the compressor. (Item 4)

[0286] The vehicle heat pump cycle device according to item 2 or 3, wherein the heat generation unit is configured to increase a heat generation amount according to a reduction in the allowable noise level of the compressor. (Item 5)

[0287] The vehicle heat pump cycle device according to item 2 or 3, wherein the expansion unit is configured to reduce a superheat degree of a refrigerant that has performed heat exchange in the heat absorption unit according to a reduction in the allowable noise level of the compressor. (Item 6)

[0288] The vehicle heat pump cycle device according to any one of items 2 to 5, wherein the upper limit speed determining unit is configured to decrease the upper limit speed when decreasing a vehicle speed. (Item 7)

[0289] The vehicle heat pump cycle device according to any one of items 2 to 5, wherein the upper limit speed determining unit is configured to decrease the upper limit speed according to a decrease in an air flow rate of a blower unit (52) configured to blow air toward a vehicle interior. (Item 8)

[0290] The vehicle heat pump cycle device according to any one of items 2 to 5, wherein the upper limit speed determining unit is configured to decrease the upper limit speed according to a decrease in an air flow rate of an outside air fan configured to blow outside air. (Item 9)

[0291] The vehicle heat pump cycle device according to any one of items 1 to 8, further comprising: a branching portion (12a) configured to branch a flow of refrigerant discharged from the compressor into one side of the heating unit and another side; a bypass passage (21c) configured to circulate a refrigerant branched at the branching portion to the other; a flow rate regulating unit (14d) configured to regulate a flow rate of refrigerant flowing through the bypass passage; and a combining unit (12f) configured to combine a refrigerant flowing out of the expansion unit and a refrigerant flowing out of the flow rate regulating unit, and cause the refrigerant to flow to an inflow port of the compressor. QUOTES CONTAINED IN THE DESCRIPTION

[0000] This list of documents submitted by the applicant was generated automatically and is included solely for the convenience of the reader. This list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions. Cited patent literature

[0000] JP 2022-179484

[0001] JP 2022-128546A

[0004]

Claims

[1] Vehicle heat pump circuit device with: a compressor (11) configured to suck in, compress and discharge a refrigerant; a heating unit (13, 131) configured to heat an object to be heated by using a refrigerant discharged from the compressor as a heat source; an expansion unit (14c) configured to expand a refrigerant flowing out of the heating unit; and a heat absorption unit (20) configured to cause a refrigerant expanded by the expansion unit to absorb heat generated by a heat generation unit (70), wherein the heat absorption unit is configured to increase a heat absorption amount according to a reduction in an allowable noise level of the compressor. [2] Vehicle heat pump circuit device with: a compressor (11) configured to suck in, compress and discharge a refrigerant; a heating unit (13, 131) configured to heat an object to be heated by using a refrigerant discharged from the compressor as a heat source; an expansion unit (14c) configured to expand a refrigerant flowing out of the heating unit; a heat absorption unit (20) configured to cause a refrigerant expanded by the expansion unit to absorb heat generated by a heat generation unit (70); and an upper limit speed determining unit (60a) configured to determine an upper limit speed of the compressor, wherein the upper limit speed determination unit is configured to lower the upper limit speed according to a reduction in a permissible noise level of the compressor, and the heat absorption unit is configured to increase a heat absorption amount in accordance with a reduction in the allowable noise level of the compressor. [3] A vehicle heat pump cycle device according to claim 2, further comprising: a target heating capacity determining unit (60d) configured to determine a target heating capacity of the heating unit, wherein the heat absorption unit is configured to increase the heat absorption amount so that the heating capacity of the heating unit approaches the target heating capacity in accordance with a reduction in the permissible noise level of the compressor. [4] The vehicle heat pump cycle device according to claim 2, wherein the heat generation unit is configured to increase a heat generation amount according to a reduction in the allowable noise level of the compressor. [5] The vehicle heat pump cycle device according to claim 2, wherein the expansion unit is configured to reduce a superheat degree of a refrigerant that has performed heat exchange in the heat absorption unit according to a reduction in the allowable noise level of the compressor. [6] The vehicle heat pump cycle device according to claim 2, wherein the upper limit speed determining unit is configured to decrease the upper limit speed when decreasing a vehicle speed. [7] The vehicle heat pump cycle device according to claim 2, wherein the upper limit speed determining unit is configured to decrease the upper limit speed according to a decrease in an air flow rate of a blower unit (52) configured to blow air toward a vehicle interior. [8] The vehicle heat pump cycle device according to claim 2, wherein the upper limit speed determining unit is configured to decrease the upper limit speed according to a decrease in an air flow rate of an outside air fan configured to blow outside air. [9] A vehicle heat pump cycle device according to any one of claims 2 to 8, further comprising: a branching portion (12a) configured to branch a flow of refrigerant discharged from the compressor into one side of the heating unit and another side; a bypass passage (21c) configured to circulate a refrigerant branched at the branch portion to the other; a flow rate regulating unit (14d) configured to regulate a flow rate of a refrigerant flowing through the bypass passage; and a combining unit (12f) configured to combine a refrigerant flowing out of the expansion unit and a refrigerant flowing out of the flow rate regulating unit, and cause the refrigerant to flow to an inflow port of the compressor.

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