Vehicle air conditioning device

Abstract

The invention provides an air conditioner for a vehicle, which can adjust the heating capability of hot-gas heating when only the rotation speed control of a compressor cannot deal with. A vehicle air-conditioning device is provided with a control device that controls a refrigerant circuit and an air-conditioning unit, the refrigerant circuit having a hot-gas bypass that decompresses at least a portion of a refrigerant compressed by a compressor and returns the refrigerant to the compressor without passing through an indoor heat exchange unit and an external heat exchange unit. The control device is capable of executing a hot-air heating operation in which a portion of the refrigerant compressed by the compressor dissipates heat in the indoor heat exchange unit and heats the interior of the vehicle without causing the refrigerant to absorb heat in the external heat exchange unit, and a hot-air heating operation in which a portion of the refrigerant compressed by the compressor dissipates heat in the indoor heat exchange unit and heats the interior of the vehicle without causing the refrigerant to absorb heat in the indoor heat exchange unit during execution of the hot-air heating operation. At least one of a pressure reduction part located between the indoor heat exchange part and the compressor and a hot gas pressure reduction part provided in the hot gas bypass is opened and closed.

Description

Technical Field

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

[0002] As an air conditioning apparatus for an electric vehicle (EV) having no combustion system heat source such as an engine or a vehicle having a low heat source of the combustion system, an air conditioning apparatus using a heat pump (refrigerant circuit) as a heat source is known.

[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 is difficult to absorb heat from the outside air, and the heating capacity is greatly reduced. In contrast, 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 an electric vehicle, there is a concern that it will have an adverse effect on the range that can be traveled, and the equipment of the PTC heater increases the manufacturing cost of the air conditioner.

[0004] Heating using hot gas from high-temperature and high-pressure refrigerant discharged from a compressor in a refrigerant circuit is a heating method that does not absorb heat and is expected to be effective in extremely low-temperature environments. This hot gas heating allows the indoor heat exchanger of a vehicle air conditioner to function as a radiator (indoor condenser), allowing the high-temperature and high-pressure refrigerant discharged from the compressor to flow directly into the radiator, and the refrigerant from the radiator is decompressed and returned to the compressor via an accumulator without passing through an external heat exchanger (see Patent Document 1 below). Prior art literature Patent Literature

[0005] Patent Document 1: Japanese Patent Application Publication No. 2014-196017 Summary of the invention Problems to be Solved by the Invention

[0006] In order to effectively maintain hot air heating, it is necessary to limit the heat dissipation of the refrigerant circuit to the indoor condenser as much as possible and balance the heat dissipation of the refrigerant circuit with the energy consumption (input heat) of the compressor. In addition, the liquid refrigerant condensed by heat dissipation in the indoor condenser must be returned to the compressor after being gasified without evaporation.

[0007] In order to achieve this purpose, in addition to the refrigerant flow path in which the high-temperature and high-pressure refrigerant coming out of the compressor is depressurized and returned to the compressor after dissipating heat in the indoor condenser, a bypass refrigerant flow path (hot gas bypass) is provided for hot gas heating by branching a part of the high-temperature and high-pressure refrigerant coming out of the compressor, depressurizing it without passing through a heat exchanger, and returning it to the compressor.

[0008] If such a hot gas bypass is provided, the gas refrigerant passing through the hot gas bypass can be mixed with the liquid refrigerant condensed by heat dissipation in the indoor condenser, and the refrigerant rich in gas can be returned to the compressor. In addition, by increasing the refrigerant flow rate flowing through the hot gas bypass, the heat dissipation in the indoor condenser can be suppressed, so by adjusting the refrigerant flow rate flowing through the hot gas bypass, the balance between the heat dissipation of the refrigerant circuit and the input heat input to the compressor can be maintained.

[0009] In such hot gas heating operation, the heating capacity can be adjusted by controlling the speed of the compressor, as in normal endothermic heating. However, in order to improve the heating capacity of hot gas heating, the speed of the compressor is sometimes operated near the upper limit. When the heating capacity needs to be further improved in such a situation, there is a problem that the speed control of the compressor alone cannot fully cope with it.

[0010] In addition, considering the durability of the compressor, the suction pressure of the compressor needs to be lowered. However, when hot air heating is continued, the suction pressure of the compressor continues to operate at a high level. Considering the durability of the compressor, it is difficult to efficiently continue hot air heating.

[0011] The present invention aims to cope with such problems. That is, the present invention aims to adjust the heating capacity of hot gas heating in situations that cannot be dealt with by the speed control of the compressor alone, to efficiently continue the hot gas heating while taking into account the durability of the compressor, and so on. Means for solving problems

[0012] In order to solve such problems, the present invention has the following configurations. 14. The air conditioning device of claim 13, wherein the air conditioning device further comprises a control device for controlling the refrigerant circuit and the air conditioning unit, wherein the refrigerant circuit comprises a hot gas bypass, wherein the hot gas bypass reduces the pressure of at least a portion of the refrigerant compressed by the compressor and returns the refrigerant to the compressor without passing through the indoor heat exchanger and the external heat exchanger. The control device is capable of performing a hot gas heating operation. In the hot gas heating operation, the refrigerant is not allowed to absorb heat in the external heat exchanger, but a portion of the refrigerant compressed by the compressor is allowed to dissipate heat in the indoor heat exchanger to heat the vehicle interior. In the execution of the hot gas heating operation, the control device adjusts the heating capacity by opening and closing at least one of a pressure reducing portion located between the indoor heat exchanger and the compressor and a hot gas pressure reducing portion provided in the hot gas bypass. Effects of the Invention

[0013] According to the present invention having such features, it is possible to adjust the heating capacity of hot gas heating which cannot be handled by only controlling the rotation speed of the compressor, and it is possible to efficiently continue hot gas heating while taking into account the durability of the compressor. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] 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 This is an explanatory diagram showing the operation flow in the hot gas heating operation. Figure 7 This is an explanatory diagram showing a configuration example of a control device for an electric vehicle (EV) including a vehicle air conditioning device. DETAILED DESCRIPTION

[0015] 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 functions, and repeated descriptions in the figures are appropriately omitted. In addition, the bold lines in the refrigerant circuit 10 in the figure represent the refrigerant flow path through which the refrigerant flows, and among the bold lines, the black bold lines represent the flow of the high-pressure refrigerant, and the gray bold lines represent the flow of the low-pressure refrigerant after decompression. In addition, the dotted lines in the refrigerant circuit 10 represent the refrigerant flow path through which the refrigerant does not flow.

[0016] [System Configuration] exist Figure 1 2 shows a configuration example of a vehicle air conditioning device 1 according to an embodiment of the present invention. The configuration example shown here is just an example, and the specific configuration is not particularly limited.

[0017] 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 disposed inside the air conditioning unit 20, and an external heat exchanger 11 disposed outside the vehicle, and they are arranged along a refrigerant flow path. The indoor heat exchangers 21 and 22 are disposed to perform heat exchange between the air flowing through the air conditioning unit 20 and the refrigerant, and the external heat exchanger 11 is disposed to perform heat exchange between the external air and the refrigerant outside the vehicle.

[0018] The compressor 2 of the refrigerant circuit 10 compresses the refrigerant and circulates the refrigerant. The refrigerant compressed by the compressor 2 is reduced to a required pressure in an appropriately selected refrigerant flow path through, for example, a first pressure reducing unit V1, a second pressure reducing unit V2, a third pressure reducing unit V3, and a fourth pressure reducing unit 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 required. In addition, an accumulator 16 for recovering liquid refrigerant and performing gas-liquid separation on the refrigerant is provided on the upstream side of the compressor 2 in the refrigerant circuit 10.

[0019] 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 into the indoor. 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 of the indoor heat exchangers 21 and 22 and is blown into the indoor. 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 into the indoor. 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.

[0020] 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 are directly heat exchanged is described, but the refrigerant and the air may be indirectly heat exchanged through a heat medium that exchanges heat with the refrigerant. That is, it is also possible to configure the refrigerant to absorb the heat of the air through the heat medium, or to release the heat of the refrigerant to the air through the heat medium.

[0021] 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 by a circulation pump 31, heats the heat medium by a heater (ECH: Electric Coolant Heater) 32, and recovers waste heat of a temperature control object such as a battery by a temperature control object heat exchanger 33. In addition, a refrigerant heat medium heat exchanger 34 is provided on the refrigerant circuit 10 and the heat medium circuit 30, which performs heat exchange between the refrigerant and the heat medium through a flow path 34A through which the refrigerant flows and a flow path 34B through which the heat medium flows.

[0022] [Control device] The vehicle air conditioning device 1 includes: Figure 2 The control device 100 shown in FIG. The control device 100 controls the 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.

[0023] The sensor unit 40 that inputs the detection signal to the control device 100 includes, for example, an outside air sensor 41 that detects the outside air state such as the outside air temperature and the outside air humidity; a compressor current sensor 42 that detects the 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; an occupant sensor 45 that detects the presence or absence of an occupant in the vehicle cabin; and a supply air temperature sensor 46 that detects the supply air temperature of the air conditioning unit 20; etc. These sensors are examples. The sensor unit 40 includes various sensors that detect information required when the control device 100 performs various controls.

[0024] The objects of control of the control device 100 are the compressor 2, the first decompression section V1, the second decompression section V2, the third decompression section V3, and the fourth decompression section V4 in the refrigerant circuit 10, the blower 23 and the dampers 24 and 25 in the air conditioning unit 20, and the circulation pump 31 in the heat medium circuit 30. In addition, the control device 100 controls the vehicle air conditioning device 1 or the notification device (e.g., display devices such as indicators and monitors, sound generating devices such as audio equipment) 3 provided in the vehicle according to the processing results of the control device 100.

[0025] [Hot gas heating operation] The hot gas heating operation does not allow the refrigerant to absorb heat in the external heat exchanger 11, but allows part or all of the refrigerant compressed by the compressor 2 to dissipate heat in the indoor heat exchanger 21, thereby heating the vehicle interior.

[0026] exist Figure 3The operation of the refrigerant circuit 10 in the hot air heating operation (including the preparatory operation) is described in the following. 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, 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 to prevent the refrigerant from flowing to the external heat exchanger 11. In addition, the fourth pressure reducing unit V4 is fully closed to prevent the refrigerant from flowing to the indoor heat exchanger 22.

[0027] The refrigerant circuit 10 includes a hot gas bypass 10V, which reduces the pressure of at least a portion of the refrigerant compressed by the compressor 2 and returns it 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 a second pressure reducing section V2 (hot gas valve), and merges with the low-pressure refrigerant reduced in pressure by a third pressure reducing section V3 at a confluence point P2 immediately upstream of the accumulator 16.

[0028] By providing such a hot gas bypass 10V, the gas refrigerant after passing through the hot gas bypass 10V can be mixed with the liquid refrigerant condensed by heat dissipation in the indoor heat exchanger 21 to become a gas-rich refrigerant and return 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 opening and closing the second pressure reducing unit V2 (hot gas valve), the refrigerant flow rate flowing through the hot gas bypass 10V is adjusted, so that the balance between the heat dissipation of the refrigerant circuit 10 and the input heat input to the compressor 2 can be maintained.

[0029] The refrigerant flow during the hot air heating operation is decompressed by the third decompression section V3 in the flow path passing through the indoor heat exchanger 21, so that the refrigerant 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, it is important to not perform heat exchange in the refrigerant heat medium heat exchanger 34 on the low-pressure side flow path in order to maintain 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 is blown into the vehicle interior.

[0030] [Ready to operate] The preparatory operation performed when the hot air heating operation is started does not perform or suppresses heat dissipation at the indoor heat exchanger 21, and circulates the refrigerant in the refrigerant circuit 10 until the refrigerant reaches a predetermined state. In one method, the operation of the refrigerant circuit 10 in the hot air heating operation is performed while the blower 23 of the air conditioning unit 20 is stopped or suppressed. In another method, the damper 24 is fully closed while the blower 23 of the air conditioning unit 20 is operated, so that no air flows to the indoor heat exchanger 21, and the operation of the refrigerant circuit 10 in the hot air heating operation is performed.

[0031] In the former method, the wind from the air conditioning unit 20 is stopped or suppressed, so as described later, it is necessary to notify the occupant that the preparatory operation is being executed. In contrast, in the latter method, the wind that does not pass through the indoor heat exchanger 21 temporarily flows from the air conditioning unit 20, so the occupant can adjust the wind volume, thereby eliminating the discomfort to the occupant.

[0032] [Endothermic heating operation] exist Figure 4 The operation of the refrigerant circuit 10 in the endothermic heating operation will be described in . In the refrigerant circuit 10 in 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.

[0033] 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 depressurized by the first pressure reducing unit V1, and the low-pressure refrigerant passes through the external heat exchanger 11, via the flow path switching valve 13, the check valve 14 and the accumulator 16, and returns to the compressor 2. At this time, the high-pressure refrigerant from the compressor 2 condenses and dissipates heat in the indoor heat exchanger 21, is depressurized by the first pressure reducing unit V1 to become a low-pressure refrigerant, absorbs heat and evaporates in 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.

[0034] [Basic Actions] exist Figure 5 100. The basic operation of the vehicle air conditioning device 1 using the control device 100 is described in the following. When the vehicle air conditioning device 1 starts to operate, the signal waiting state of the air conditioning instruction signal is entered (step S01). Here, if the heating instruction is input (step S01: "Yes"), the next step S02 is transferred. If an instruction other than the heating instruction (for example, the cooling instruction) is input (step S01: "No"), the other air conditioning control is transferred to another instruction (step S01A).

[0035] In the next step S02, it is determined whether to perform the hot air heating operation. The hot air heating operation is mainly performed when the heat absorption heating cannot be performed. Therefore, for example, when the outside air sensor 41 detects an extremely low temperature, if it is determined that the hot air heating operation should be performed (step S02: "Yes"), the next step S03 is transferred. If 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.

[0036] 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 refrigerant recovery is required (step S03: "Yes"), refrigerant recovery processing is performed (step S04). In addition, in step S03, if it is determined that refrigerant recovery is not required (step S03: "No"), the refrigerant recovery processing (step S04) is skipped. In addition, in steps S09 and S10 after the heating is completed, if the refrigerant recovery processing is performed, steps S03 and S04 here can be omitted.

[0037] In step S05, the above-mentioned preparatory operation performed when the hot air heating operation is started is performed. In the preparatory operation, the refrigerant circuit 10 in the above-mentioned hot air heating operation is operated without or with the heat dissipation from the refrigerant circuit 10 suppressed, so that the circulating refrigerant becomes a high-pressure state and the refrigerant accumulates energy. In this preparatory operation (step S05), as described above, the blower 23 of the air conditioning unit 20 is stopped.

[0038] Then, in step S06, the preparatory operation (step S05) is continued until it is determined that the refrigerant state is suitable for hot air heating operation (step S06: "No"), but during this period, the occupants in the vehicle cabin are notified of the preparatory operation for hot air heating operation so that the occupants do not feel uneasy or uncomfortable due to equipment failure due to the wind blowing from the air-conditioning unit 20 (step S06A).

[0039] The notification to the occupants here (occupant notification: step S06A) is performed by outputting from the control device 100 to the notification device 3, and notifying the occupants that the above-mentioned preparatory operation is being executed. As an example, a display device such as an indicator or a monitor provided in the vehicle is displayed by flashing or by displaying on the monitor. As another example, a sound or a predetermined notification sound is emitted from a speaker provided in the vehicle, thereby notifying the occupants that the above-mentioned preparatory operation is being executed. In this way, the occupants can recognize that the current situation of not blowing air is not a malfunction of the machine, but a normal preparatory operation for the hot air heating operation.

[0040] If it is confirmed that sufficient refrigerant energy has been accumulated 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 judged to be completed (step S06: Yes), and the hot air heating operation with air supply is performed (step S07).

[0041] The hot air heating operation is performed until the heating end instruction is input (step S08: "No"), and 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) in the same manner as steps S03 and S04, and the air conditioning operation is terminated. In addition, when steps S03 and S04 are executed at the next air conditioning operation, steps S09 and S10 can be omitted.

[0042] When heat absorption heating operation is performed in step S11, the operation is continued until the subsequent heating end instruction is issued (step S12: "No"). If the heating end instruction is issued (step S12: "Yes"), 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.

[0043] [Adjustment of heating capacity during hot gas heating operation] When there is an indication to adjust the heating capacity during the hot gas heating operation, the speed adjustment of the compressor and the adjustment of the pressure reducing section (the second pressure reducing section V2 and the third pressure reducing section V3) of the hot gas heating refrigerant flow path are appropriately combined to perform control corresponding to the adjustment indication, taking into account the urgency of the indication, the speed condition of the compressor or the burden on the compressor.

[0044] exist Figure 6 An example of the adjustment operation during the hot gas heating operation (step S07) is described in . During the hot gas heating operation (step S07), if an adjustment instruction for the heating capacity is input (step S07A: "Yes"), it is determined whether the adjustment instruction is an instruction to increase the heating capacity or an instruction to decrease the heating capacity (step S07B).

[0045] In the case of an indication of an increase in the heating capacity (step S07B: "Yes"), based on the condition of the rotational speed of the compressor 2, when the rotational speed is near the upper limit value (step S07C: "Yes"), the indication of an increase in the heating capacity is responded to by opening and adjusting the second pressure reducing portion V2 (hot gas valve) on the hot gas bypass 10V, and when the rotational speed of the compressor 2 is not near the upper limit value (step S07C: "No"), the indication of an increase in the heating capacity is responded to by increasing the rotational speed of the compressor 2 (S07K).

[0046] At this time, if the second pressure reducing unit V2 is opened, the refrigerant flow rate flowing through the hot gas bypass 10V increases, so the refrigerant flow rate returning to the compressor 2 increases, the load of the compressor 2 increases, and the power consumption increases, so the heat dissipation in the hot gas heating operation increases, and the heating capacity increases. In addition, when the speed of the compressor 2 is increased, the power consumption of the compressor 2 also increases, and the heating capacity in the hot gas heating operation increases.

[0047] When the suction pressure of the compressor 2 reaches the upper limit in order to increase the heating capacity (step S07E: Yes), the second pressure reducing unit V2 is closed (step S07F) to reduce the burden on the compressor 2. By making such an adjustment, the durability of the compressor 2 can be ensured.

[0048] If the heating capacity adjustment instruction is an instruction to reduce the heating capacity (step S07B: "No"), it is determined whether a rapid reduction is required based on the instruction content (step S07G). Here, for example, in response to a sudden change in the outside air temperature such as an emergency manual adjustment by an occupant or driving in a tunnel, it is determined that a rapid reduction is required, and in response to a steady change in the outside air temperature, it is determined that a rapid reduction is not required.

[0049] If it is determined that a rapid reduction is required (step S07G: "Yes"), the rotation speed of the compressor 2 is reduced (step S07I), thereby responding to the instruction to reduce the heating capacity. If it is determined that a rapid reduction is not required (step S07G: "No"), the second pressure reducing unit V2 of the hot gas bypass 10V is closed (step S07H), thereby responding to the instruction to reduce the heating capacity. If there is no instruction to adjust the heating capacity during the hot gas heating operation (step S07A: "No"), the current heating capacity is maintained (step S07J).

[0050] In addition, Figure 6 In the operation example shown, the opening and closing adjustment of the second decompression part V2 can be replaced by the opening and closing adjustment of the third decompression part V3, or can be performed by the cooperation of the second decompression part V2 and the third decompression part V3. Figure 6In the action example shown, when the suction pressure of the compressor 2 reaches near the upper limit (step S07E: "Yes"), in order to reduce the burden on the compressor 2, the second pressure reducing section V2 is adjusted to be closed (step S07F), but when the discharge pressure of the compressor 2 is at the upper limit value or the air volume of the blower 23 installed in the air-conditioning unit 20 is at the upper limit value, the second pressure reducing section V2 may also be adjusted to be closed.

[0051] [Configuration of electric vehicle (EV) control device] 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) through 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 is connected to each other via a bus 106.

[0052] 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 when CPU101 executes a program. Input / 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. In-vehicle communication I / F105 controls data transmission and reception with other ECUs set in the EV by connecting to the vehicle network L.

[0053] The control device 100 receives data on surrounding environmental 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 conditioner 1 through a program executed by the CPU 101 .

[0054] The EV is equipped with a battery B. The battery B is charged by connecting a charger plug PS to a battery plug BP, and the vehicle air conditioner 1 is powered by the battery B. The connection between the plug PS and the battery plug BP is transmitted to the control device 100 via the vehicle network L as a charger connection signal.

[0055] The embodiments of the present invention are described in detail above with reference to the accompanying drawings, but the specific configuration is not limited to these embodiments, and even changes in design that do not deviate from the scope of the present invention are also included in the present invention. In addition, the above-mentioned embodiments can be combined with each other's technology as long as there are no special contradictions or problems in their purposes and configurations. Description of reference numerals:

[0056] 1: Vehicle air conditioning device; 2: Compressor; 3: Notification device (display device); 10: Refrigerant circuit; 10V: Hot gas bypass; 11: External heat exchanger; 12, 13: Flow path switching valve; 14, 15: Check valve; 16: Liquid storage tank; 20: Air conditioning unit; 21, 22: Indoor heat exchanger; 23: Blower; 30: Heat medium circuit; 31: Circulation pump; 32: Heater; 33: Temperature adjustment object heat exchanger; 34: Refrigerant heat medium heat exchanger; 24, 25: Adjustment damper; 25A, 25B: Air inlet; 40: Sensor unit; 41: External air sensor; 42: Compressor current sensor; 43: Refrigerant temperature sensor; 44: Refrigerant pressure sensor; 45: Occupant sensor; 46: Air supply temperature sensor; 100: Control device; V1: First pressure reducing unit; V2: Second pressure reducing unit; V3: Third pressure reducing unit; V4: Fourth pressure reducing unit.

Claims

1. A vehicle air conditioning device, characterized in that: have: A refrigerant circuit including a compressor, an indoor heat exchange portion, and an external heat exchange portion; 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 refrigerant circuit includes a hot gas bypass that decompresses at least a portion of the refrigerant compressed by the compressor without passing through the indoor heat exchange portion and the external heat exchange portion and returns the decompressed refrigerant to the compressor. The control device is capable of performing a hot air heating operation in which a portion of the refrigerant compressed by the compressor is allowed to dissipate heat in the indoor heat exchange portion to heat the vehicle interior without causing the refrigerant to absorb heat in the external heat exchange portion. The control device adjusts the heating capacity by opening and closing at least one of a decompression section located between the indoor heat exchange section and the compressor and a hot gas decompression section provided in the hot gas bypass during hot gas heating operation.

2. The vehicle air conditioning device according to claim 1, characterized in that: The control device performs opening adjustment of the decompression section or the hot gas decompression section in response to the capacity increase instruction of the hot gas heating operation when the rotation speed of the compressor is near an upper limit value.

3. The vehicle air conditioning device according to claim 1, characterized in that: In response to the capacity increase instruction of the hot gas heating operation, the control device performs closing adjustment on the decompression section or the hot gas decompression section when the suction pressure of the compressor is at an upper limit value.

4. The vehicle air conditioning device according to claim 1, characterized in that: In response to the capacity increase instruction of the hot gas heating operation, the control device performs closing adjustment on the pressure reducing unit or the hot gas pressure reducing unit when the discharge pressure of the compressor is at an upper limit value.

5. The vehicle air conditioning device according to claim 1, characterized in that: In response to the capacity increase instruction of the hot air heating operation, the control device performs closing adjustment on the pressure reducing section or the hot air pressure reducing section when the air volume of the blower provided in the air conditioning unit is at an upper limit value.

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