Vehicle air conditioning device

Abstract

When an air conditioner is started before a passenger is boarding, an external heat exchange part for absorbing heat of external air is prevented from being frosted, and air conditioning before and after the passenger is boarding is performed efficiently. The vehicle air-conditioning device includes: a refrigerant circuit including a compressor, an indoor heat exchange unit, and an external heat exchange unit; an air-conditioning unit in which the indoor heat exchange unit is disposed; and a control device that controls the refrigerant circuit and the air-conditioning unit, the refrigerant circuit having a hot gas bypass that depressurizes at least a portion of the refrigerant compressed by the compressor and returns the refrigerant to the compressor without passing through the indoor heat exchange unit and the external heat exchange unit. The control device can selectively execute a heat absorption heating operation in which the external heat exchange unit absorbs heat from the outside air, and a hot air heating operation in which the refrigerant does not absorb heat from the external heat exchange unit but a portion of the refrigerant compressed by the compressor is dissipated by the indoor heat exchange unit. A hot-gas heating operation is selected before a passenger is boarding the vehicle and when the charger is connected to the vehicle.

Description

Technical Field

[0001] The present invention relates to a vehicle air conditioning device. Background Art

[0002] Air conditioning apparatuses for electric vehicles (EVs) that do not have a heat source of a combustion system such as an engine or for vehicles with a low heat source of a combustion system have been known that use a heat pump (refrigerant circuit) as a heat source.

[0003] In the case of an air conditioner using a heat pump, the external heat exchanger functions as a heat absorber during heating operation, and obtains a heating heat source from the outside air. Therefore, if the outside air temperature becomes extremely low, it becomes difficult to absorb heat from the outside air, and the heating capacity is greatly reduced. In this regard, if an electric heater such as a PTC heater is used to ensure a heat source, the battery consumption increases, and in the case of electric vehicles, there is a concern that this may have a negative impact on the cruising range, and the equipment of a PTC heater may increase the manufacturing cost of the air conditioner.

[0004] Heating with hot air from high-pressure, high-temperature refrigerant discharged from a compressor of a refrigerant circuit is a heating method that does not absorb heat, and is expected to be effective heating in extremely low-temperature environments. In this hot air heating, the interior heat exchanger of a vehicle air conditioner functions as a radiator (interior condenser), into which the high-pressure, high-temperature refrigerant discharged from the compressor flows directly, and after the refrigerant discharged from the radiator is depressurized, it returns to the compressor via an accumulator instead of an external heat exchanger (see Patent Document 1 below).

[0005] Patent Document 1: Japanese Patent Application Publication No. 2014-196017

[0006] A vehicle air conditioning device capable of hot air heating performs hot air heating when heat cannot be absorbed from the outside air, etc., and performs endothermic heating when heat can be absorbed from the outside air, etc., by switching the refrigerant flow path for hot air heating and the refrigerant flow path for normal heat absorption heating.

[0007] In this regard, in order to ensure the comfort of passengers who have just boarded the vehicle, there is an action mode for starting the air conditioning before boarding. However, in this action mode, if heat absorption and heating are performed according to external air conditions, sometimes the external heat exchanger used to absorb heat from the external air will be frosted, and not only can the air conditioning before the passengers board not be performed efficiently, but the heat absorption and heating after the passengers board cannot be performed efficiently either. Summary of the invention

[0008] The problem of the present invention is to deal with such a situation. That is, the problem of the present invention is to prevent frost formation of an external heat exchanger that absorbs heat from the outside air when the air conditioning is started before passengers get on board in a vehicle air conditioning device that can switch between hot air heating operation and intake air heating operation, so as to efficiently perform air conditioning before and after passengers get on board.

[0009] In order to solve the above-mentioned problems, the present invention has the following configurations. The vehicle air conditioning device comprises: a refrigerant circuit including a compressor, an indoor heat exchanger and an external heat exchanger; an air conditioning unit, in which the indoor heat exchanger is arranged; and a control device for controlling the refrigerant circuit and the air conditioning unit, wherein the refrigerant circuit has a hot gas bypass, the hot gas bypass causes at least a portion of the refrigerant compressed by the compressor to be decompressed and returned to the compressor without passing through the indoor heat exchanger and the external heat exchanger, the control device can selectively perform heat absorption heating operation and hot gas heating operation, in which the external air absorbs heat through the external heat exchanger, and in which the refrigerant does not absorb heat in the external heat exchanger, but a portion of the refrigerant compressed by the compressor dissipates heat through the indoor heat exchanger, and the control device selects the hot gas heating operation before passengers board the vehicle and when the charger is connected to the vehicle.

[0010] According to the present invention having such features, since the hot air heating operation is selected when the charger is connected to the vehicle before passengers board the vehicle, when the air conditioning is started before passengers board, frosting of the external heat exchanger that absorbs heat from the outside air can be prevented, thereby efficiently performing the air conditioning before and after passengers board. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Figure 1 It is an explanatory diagram showing an example of the system configuration of a vehicle air conditioning device according to an embodiment of the present invention. Figure 2 It is an explanatory diagram showing a control device for a vehicle air conditioning system according to an embodiment of the present invention. Figure 3 It is an explanatory diagram showing the operation of the refrigerant circuit in the hot gas heating operation of the vehicle air conditioner according to the embodiment of the present invention. Figure 4 It is an explanatory diagram showing the operation of the refrigerant circuit in the heat absorption heating operation of the vehicle air conditioning system according to the embodiment of the present invention. Figure 5 It is an explanatory diagram showing a basic operation flow of the vehicle air conditioning device according to the embodiment of the present invention. Figure 6 It is an explanatory diagram showing a modified example of the basic operation flow of the vehicle air conditioning device according to the embodiment of the present invention. Figure 7 This is an explanatory diagram showing a configuration example of a control device in an electric vehicle (EV) including a vehicle air conditioner. DETAILED DESCRIPTION

[0012] Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. In the following description, the same reference numerals in different figures represent parts with the same function, and repeated descriptions in the figures are appropriately omitted. In addition, the bold lines in the refrigerant circuit 10 in the figure represent refrigerant flow paths for refrigerant circulation, the black bold lines in the bold lines represent high-pressure refrigerant flow, and the gray bold lines represent low-pressure refrigerant flow after decompression. In addition, the dotted lines in the refrigerant circuit 10 represent refrigerant flow paths through which refrigerant does not circulate.

[0013] (System Structure) Figure 1 A configuration example of a vehicle air conditioning device 1 according to an embodiment of the present invention is shown. The configuration example shown here is just an example, and the specific configuration is not particularly limited.

[0014] The vehicle air conditioning device 1 includes a refrigerant circuit 10 and an air conditioning unit 20. The refrigerant circuit 10 includes a compressor 2, indoor heat exchangers 21 and 22 provided inside the air conditioning unit 20, and an external heat exchanger 11 provided outside the vehicle, which are arranged along a refrigerant flow path. The indoor heat exchangers 21 and 22 are provided to exchange heat between the air flowing through the air conditioning unit 20 and the refrigerant, and the external heat exchanger 11 is provided to exchange heat between the external air and the refrigerant outside the vehicle.

[0015] The compressor 2 of the refrigerant circuit 10 compresses the refrigerant and circulates the refrigerant. The refrigerant compressed by the compressor 2 is decompressed to a necessary pressure in an appropriately selected refrigerant flow path through, for example, a first decompression section V1, a second decompression section V2, a third decompression section V3, and a fourth decompression section V4, which are expansion valves. The refrigerant circuit 10 is provided with flow path switching valves 12 and 13 for switching the refrigerant flow path, and check valves 14 and 15 for limiting the flow direction of the refrigerant are provided as needed. Moreover, on the upstream side of the compressor 2 in the refrigerant circuit 10, a liquid accumulator 16 for recovering liquid refrigerant and separating the refrigerant into gas and liquid is provided.

[0016] As described above, the air conditioning unit 20 is provided with indoor heat exchangers 21 and 22 inside, and the air introduced from indoor or outdoor by the blower 23 selectively passes through the indoor heat exchangers 21 and 22 and is blown indoors. The air conditioning unit 20 is provided with a damper 24. When the damper 24 is fully opened as shown in the figure, the air introduced by the blower 23 passes through both indoor heat exchangers 21 and 22 and is blown indoors, and when the damper 24 is fully closed, the air introduced by the blower 23 passes only through the indoor heat exchanger 22 and is blown indoors. Another damper 25 provided in the air conditioning unit 20 switches the air introduced to the blower 23 between indoor and outdoor, and selectively closes the air inlet 25A connected to the outdoor and the air inlet 25B connected to the indoor.

[0017] In addition, in the above-mentioned external heat exchanger 11 and indoor heat exchangers 21 and 22, an example in which the refrigerant and the air directly exchange heat is described, but the refrigerant and the air may also exchange heat indirectly via a heat medium that exchanges heat with the refrigerant. That is, it is also possible to configure the refrigerant to absorb heat from the air via the heat medium, or to release heat from the refrigerant to the air via the heat medium.

[0018] In addition, the vehicle air conditioning device 1 is provided with a heat medium circuit 30 as required. The heat medium circuit 30 circulates the heat medium through a circulation pump 31, heats the heat medium through a heater (ECH: Electric Coolant Heater) 32, or recovers waste heat from a temperature control object such as a battery through a temperature control object heat exchanger 33. In addition, a refrigerant heat medium heat exchanger 34 is provided in the refrigerant circuit 10 and the heat medium circuit 30, and the refrigerant heat medium heat exchanger 34 performs heat exchange between the refrigerant and the heat medium through a flow channel 34A through which the refrigerant flows and a flow channel 34B through which the heat medium flows.

[0019] (Control device) The vehicle air conditioning device 1 includes: Figure 2 The control device 100 shown in FIG. The control device 100 controls the aforementioned refrigerant circuit 10 and the air conditioning unit 20 based on various input signals (air conditioning instruction signal, charger connection signal, etc.) and detection signals from the sensor unit 40, and controls the heat medium circuit 30 as needed.

[0020] The sensor unit 40 that inputs a detection signal to the control device 100 includes, for example, an outside air sensor 41 that detects outside air conditions such as outside air temperature and outside air humidity, a compressor current sensor 42 for detecting power consumption (energy consumption) of the compressor 2, a refrigerant temperature sensor 43 and a refrigerant pressure sensor 44 that detect the state of the refrigerant, a passenger sensor 45 that detects the presence or absence of passengers in the vehicle cabin, and an air supply temperature sensor 46 that detects the air supply temperature of the air conditioning unit 20. These sensors are only examples. The sensor unit 40 includes various sensors for detecting information required when the control device 100 performs various controls.

[0021] In the refrigerant circuit 10, the control objects of the control device 100 are the compressor 2, the first decompression part V1, the second decompression part V2, the third decompression part V3, and the fourth decompression part V4, etc. In the air conditioning unit 20, the control objects of the control device 100 are the blower 23 and the dampers 24 and 25, etc. In the heat medium circuit 30, the control objects of the control device 100 are the circulation pump 31, etc. In addition, the control device 100 controls the vehicle air conditioning device 1 according to the processing results of the control device 100.

[0022] (Hot gas heating operation) In the hot air heating operation, the refrigerant does not absorb heat in the external heat exchanger 11, but part or all of the refrigerant compressed by the compressor 2 dissipates heat through the indoor heat exchanger 21 to heat the vehicle interior.

[0023] use Figure 3 The operation of the refrigerant circuit 10 in the hot air heating operation (including the preparatory operation) is described. In this operation, a part of the high-temperature and high-pressure refrigerant discharged from the compressor 2 passes through the indoor heat exchanger 21 and the flow path switching valve 12, is reduced in pressure by the third pressure reducing unit V3 to become a low-pressure refrigerant, passes through the refrigerant heat medium heat exchanger 34, and is separated into gas and liquid by the accumulator 16, and returns to the compressor 2. At this time, in the refrigerant circuit 10, the first pressure reducing unit V1 is fully closed, so that the refrigerant does not flow to the external heat exchanger 11. In addition, the fourth pressure reducing unit V4 is fully closed, and the refrigerant does not flow to the indoor heat exchanger 22.

[0024] The refrigerant circuit 10 has a hot gas bypass 10V that reduces the pressure of at least a portion of the refrigerant compressed by the compressor 2 and returns to the compressor 2 without passing through the indoor heat exchanger 21 and the external heat exchanger 11. In the hot gas bypass 10V, a portion of the high-temperature and high-pressure refrigerant is branched at a branch point P1 immediately downstream of the compressor 2, is reduced in pressure by the second pressure reducing section V2 (hot gas valve), and merges with the low-pressure refrigerant reduced in pressure by the third pressure reducing section V3 at a confluence point P2 immediately upstream of the accumulator 16.

[0025] By providing such a hot gas bypass 10V, the gas refrigerant passing through the hot gas bypass 10V can be mixed with the liquid refrigerant condensed by heat dissipation in the indoor heat exchanger 21, and the refrigerant becomes gas-rich and then returns to the compressor 2. In addition, by increasing the refrigerant flow rate flowing through the hot gas bypass 10V, the heat dissipation in the indoor heat exchanger 21 can be suppressed, and by adjusting the refrigerant flow rate flowing through the hot gas bypass 10V by opening and closing the second pressure reducing unit V2 (hot gas valve), the balance between the heat dissipation of the refrigerant circuit 10 and the input heat input to the compressor 2 can be maintained.

[0026] The refrigerant flow during the hot air heating operation is decompressed by the third decompression section V3 in the flow passage passing through the indoor heat exchanger 21, so it becomes a high-pressure refrigerant on the upstream side of the third decompression section V3 and becomes a low-pressure refrigerant on the downstream side of the third decompression section V3. At this time, heat exchange is not performed in the refrigerant heat medium heat exchanger 34 in the low-pressure side flow passage, which is important for maintaining the heating capacity. In addition, in the air conditioning unit 20, the air introduced by the blower 23 is heated by heat dissipation in the indoor heat exchanger 21 and blown into the vehicle interior.

[0027] (Ready to operate) In the preparatory operation performed when the hot air heating operation is started, until the refrigerant reaches a predetermined state, heat dissipation in the indoor heat exchanger 21 is not performed or suppressed, and the refrigerant is circulated through the refrigerant circuit 10. One method is to perform the operation of the refrigerant circuit 10 in the hot air heating operation described above while stopping or suppressing the blower 23 of the air conditioning unit 20. In addition, another method is to fully close the damper 24 in the state where the blower 23 of the air conditioning unit 20 is operated, so that the indoor heat exchanger 21 is not ventilated, and the operation of the refrigerant circuit 10 in the hot air heating operation described above is performed.

[0028] In the preparatory operation, the former method stops or suppresses the wind from the air conditioning unit 20 , and the latter method temporarily flows the wind from the air conditioning unit 20 without passing through the indoor heat exchanger 21 .

[0029] (Heat absorption heating operation) use Figure 4 The operation of the refrigerant circuit 10 during the endothermic heating operation will be described. In the refrigerant circuit 10 during the endothermic heating operation, the second decompression section V2, the third decompression section V3, the fourth decompression section V4 and the flow path switching valve 12 are all fully closed.

[0030] In the heat absorption heating operation, the high-temperature and high-pressure refrigerant discharged from the compressor 2 passes through the indoor heat exchanger 21 in the air conditioning unit 20, is decompressed by the first pressure reducing part V1, and the low-pressure refrigerant passes through the external heat exchanger 11, and returns to the compressor 2 via the flow path switching valve 13, the check valve 14 and the accumulator 16. At this time, the high-pressure refrigerant discharged from the compressor 2 is condensed and radiates heat by the indoor heat exchanger 21, is decompressed by the first pressure reducing part V1 to become a low-pressure refrigerant, and absorbs heat and evaporates by the external heat exchanger 11, and returns to the compressor 2. In addition, in the air conditioning unit 20, the air introduced by the blower 23 is heated by the heat dissipation in the indoor heat exchanger 21 and is blown into the vehicle interior.

[0031] (Basic Action) use Figure 5 The basic operation of the vehicle air conditioning device 1 implemented by the control device 100 will be described. When the vehicle air conditioning device 1 starts to operate, it enters a signal waiting state for an air conditioning instruction signal (step S01). If a heating instruction is input (step S01: Yes), the process moves to the next step S02. If an instruction other than the heating instruction (for example, a cooling instruction) is input (step S01: No), the process moves to other air conditioning control corresponding to the instruction (step S01A).

[0032] In the next step S02, it is determined whether the hot air heating operation is to be performed. Since the hot air heating operation is mainly performed when the heat absorption heating cannot be performed, for example, when the outside air sensor 41 detects an extremely low temperature condition and it is determined that the hot air heating operation should be performed (step S02: Yes), the process moves to the next step S03. In the case where it is determined in step S02 that the hot air heating operation is not to be performed (step S02: No), the above-mentioned intake air heating operation (step S11) is performed.

[0033] In step S03, it is determined whether condensed refrigerant is accumulated in the external heat exchanger 11, the refrigerant heat medium heat exchanger 34, etc. in the refrigerant circuit 10 based on the state of the refrigerant in the refrigerant circuit 10, the state of the heating operation before startup, etc. If it is determined that refrigerant is accumulated and needs to be recovered (step S03: yes), refrigerant recovery processing (step S04) is performed. In addition, if it is determined in step S03 that refrigerant recovery is not required (step S03: no), the refrigerant recovery processing (step S04) is skipped. In addition, if the refrigerant recovery processing is performed in steps S09 and S10 after the heating is completed, steps S03 and S04 here can be omitted.

[0034] In step S05, the aforementioned preparatory operation performed when the hot air heating operation is started is performed. In the preparatory operation, the operation of the refrigerant circuit 10 in the hot air heating operation is performed in a state where heat dissipation from the refrigerant circuit 10 is not or is suppressed, so that the circulating refrigerant becomes a high-pressure state and energy is accumulated in the refrigerant. In this preparatory operation (step S05), as described above, the blower 23 of the air conditioning unit 20 is stopped.

[0035] Then, in step S06 , the preparatory operation (step S05 ) is continued until it is determined that the refrigerant state is suitable for the hot gas heating operation (step S06 : No).

[0036] If it is confirmed that sufficient energy has been stored in the refrigerant during the preparatory operation based on the detection results of the refrigerant pressure and the power consumption of the compressor 2, the preparatory operation is determined to be completed (step S06: Yes), and the hot air heating operation with air supply is performed (step S07).

[0037] The hot air heating operation is performed until the heating end instruction is input (step S08: No). If the heating end instruction is input (step S08: Yes), the necessity of refrigerant recovery is determined (step S09) and the refrigerant recovery process is performed if necessary (step S10) as in steps S03 and S04, and the air conditioning operation is terminated. In addition, when steps S03 and S04 are performed at the next air conditioning operation, steps S09 and S10 can be omitted.

[0038] When heat absorption heating operation is performed in step S11, the operation continues until the subsequent heating end instruction is issued (step S12: No). If the heating end instruction is issued (step S12), the necessity of refrigerant recovery is determined (step S09) and the refrigerant recovery process is performed if necessary (step S10), and the air conditioning operation is terminated.

[0039] (Variation of the basic action) In order to ensure the comfort of passengers who have just boarded the vehicle, the vehicle air conditioning device 1 can be used as a trigger, for example, by starting the vehicle air conditioning device 1 at a preset start time or by the operation of the passenger, so that the air conditioning operation can be started before the passengers board the vehicle. In particular, when the pre-performed air conditioning is heating, the following control can be performed to efficiently perform the air conditioning before and after the passengers board the vehicle.

[0040] In the vehicle air conditioner 1, when heating is performed in advance, even if the heat absorption heating operation can be performed according to the external air conditions, when the vehicle equipped with the vehicle air conditioner 1 is connected to the charger, the hot air heating operation is still performed. By controlling in this way, the heating operation in the vehicle interior is performed without absorbing heat from the external heat exchanger 11, and the air conditioning in the vehicle interior can be performed in advance while preventing the external heat exchanger 11 from frosting, thereby improving the efficiency of the air conditioning before and after the passengers get on board.

[0041] Generally, since the hot air heating operation consumes more electricity than the endothermic heating operation, it is preferred not to perform the hot air heating operation when the endothermic heating operation can be performed, considering the impact on the vehicle's cruising range. On the other hand, when the vehicle is connected to the charger, since the charger supplies electricity, there is no need to consider the impact on the vehicle's cruising range. Therefore, when the vehicle is connected to the charger, by performing the hot air heating operation, the air conditioning of the vehicle interior is performed in advance while preventing the external heat exchanger 11 from frosting. Figure 6 A modified example of the basic operation of the vehicle air conditioning device 1 including such an operation will be described.

[0042] exist Figure 6 In the aspect of determining whether the vehicle is connected to the charger (step S13) after the heating instruction is input (step S01: Yes) and before determining whether to perform hot air heating (step S02), the Figure 6 The basic action is different, and other processing is the same as Figure 5 Since the steps are common, descriptions of the processing related to the common steps will be omitted.

[0043] exist Figure 6 In the case where the vehicle is connected to the charger (step S13: Yes), the judgment of whether to perform hot air heating in step S02 is skipped, and the judgment of whether to recover the refrigerant in step S03 is transferred to the subsequent processing of steps S04 to S12 according to the judgment result. In the case where the vehicle is not connected to the charger (step S13: No), the judgment of whether to perform hot air heating in step S02 is performed, and the subsequent processing of steps S03 to S12 is performed according to the judgment result.

[0044] As described later, when the battery plug BP of the battery B mounted on the vehicle is connected to the charger plug PS, a charger connection signal (see Figure 7 ). The control device 100 determines whether the vehicle is connected to the charger by determining whether a charger connection signal is received.

[0045] exist Figure 6In the example of , a determination is made in step S13 whether the vehicle is connected to the charger, and the hot air heating operation is performed when the vehicle is connected to the charger, but the hot air heating operation may be performed before passengers board the vehicle and when the charger is connected to the vehicle. In addition, even when the charger is connected to the vehicle, the hot air heating operation may be performed when the outside air temperature is below a predetermined threshold. The threshold of the outside air temperature may be determined according to the desired conditions, for example, 0°C at which frost forms on the outside heat exchange portion 11 may be set as the threshold.

[0046] (Structure of control device in electric vehicle (EV)) like Figure 7 As shown, the control device 100 provided in the vehicle air conditioning device 1 is configured as one ECU connected to various ECUs (Electronic Control Units) that control the electric vehicle (EV) via the vehicle network L. The control device 100 includes a CPU (Central Processing Unit) 101, a ROM (Read Only Memory) 102, a RAM (Random Access Memory) 103, an input / output I / F (Interface) 104, and an in-vehicle communication I / F (Interface) 105, and the hardware components are connected to each other via a bus 106.

[0047] CPU101 controls the control device 100 by executing various programs stored in ROM102. ROM102 is a non-volatile memory. For example, ROM102 stores programs executed by CPU101, data required for CPU101 to execute programs, etc. RAM103 is a main storage device such as DRAM (Dynamic Random Access Memory) and SRAM (Static Random Access Memory). For example, RAM103 functions as a work area used by CPU101 when executing a program. The input and output I / F104 is connected to various sensors and monitors installed in the EV, inputs data to CPU101, and outputs data obtained by CPU101 calculation and processing. The in-vehicle communication I / F105 controls the data transmission and reception with other ECUs set in the EV by connecting to the vehicle network L.

[0048] The control device 100 receives data on surrounding environment information or data on the operating status of the EV via the input / output I / F 104 and the in-vehicle communication I / F 105 , and controls the vehicle air conditioning device 1 described above by a program executed by the CPU 101 .

[0049] Battery B is mounted on the EV. Battery B is charged by connecting a charger plug PS to battery plug BP, and power is supplied to vehicle air conditioner 1 via battery B. When plug PS is connected to battery plug BP, a charger connection signal is transmitted to control device 100 via vehicle network L.

[0050] The embodiments of the present invention are described in detail above with reference to the accompanying drawings, but the specific structure is not limited to these embodiments, and even if there are design changes within the scope of the gist of the present invention, they are also included in the present invention. In addition, as long as there are no special contradictions or problems in the purposes and structures of the above-mentioned embodiments, the technologies of each other can be used for combination. Description of Reference Numerals

[0051] 1: Vehicle air conditioning device, 2: Compressor, 10: Refrigerant circuit, 10V: Hot gas bypass, 11: External heat exchanger, 12, 13: channel switching valve, 14, 15: check valve, 16: liquid reservoir, 20: air conditioning unit, 21, 22: indoor heat exchanger, 23: blower, 30: heat medium circuit, 31: circulation pump, 32: heater, 33: Temperature control object heat exchanger, 34: Refrigerant heat medium heat exchanger, 24, 25: air doors, 25A, 25B: air inlets, 40: sensor unit, 41: outside air sensor, 42: compressor current sensor, 43: Refrigerant temperature sensor, 44: Refrigerant pressure sensor, 45: Passenger sensor, 46: Supply air temperature sensor, 100: control device, V1: first decompression section, V2: second decompression section, V3: third decompression section, V4: fourth decompression section.

Claims

1. A vehicle air conditioning device, comprising: A refrigerant circuit including a compressor, an indoor heat exchange section and an external heat exchange section; an air conditioning unit, in which the indoor heat exchange portion is disposed; as well as a control device for controlling the refrigerant circuit and the air conditioning unit, The vehicle air conditioning device is characterized in that: The refrigerant circuit includes a hot gas bypass that reduces the pressure of at least a portion of the refrigerant compressed by the compressor and returns to the compressor without passing through the indoor heat exchange part and the external heat exchange part. The control device can selectively perform heat absorption heating operation and hot air heating operation. In the heat absorption heating operation, the external air absorbs heat through the external heat exchange part. In the hot air heating operation, the refrigerant does not absorb heat in the external heat exchange part, but a part of the refrigerant compressed by the compressor dissipates heat through the indoor heat exchange part. The control device selects the hot gas heating operation when a charger is connected to the vehicle.

2. The vehicle air conditioning device according to claim 1, characterized in that: The control device selects the hot air heating operation when the heating operation is being executed before a passenger gets on the vehicle and when a charger is connected to the vehicle.

3. The vehicle air conditioning device according to claim 1, characterized in that: The control device selects the hot air heating operation when the outside air temperature is equal to or lower than a predetermined threshold value.

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