Vehicle air conditioning device

Abstract

By performing defrosting of an external heat exchanger while performing hot gas heating operation, a transition from hot gas heating operation to heat absorption heating operation can be smoothly performed.The vehicle air conditioning device comprises a control device that controls a refrigerant circuit and an air conditioning unit, wherein the refrigerant circuit has a hot gas bypass, wherein the control device can selectively execute a hot gas heating operation in which the refrigerant in the external heat exchanger section does not absorb heat and a part of the refrigerant compressed in the compressor releases heat in the internal heat exchanger section to heat a passenger compartment, and a heat absorption heating operation in which the refrigerant absorbs heat at the external heat exchanger section, wherein, during the execution of the hot gas heating operation, defrosting of the external heat exchanger section is performed by flowing refrigerant that has flowed through the internal heat exchanger section to the external heat exchanger section.

Description

TECHNICAL FIELDThe present invention relates to a vehicle air conditioning apparatus.PRIOR ARTAs an air conditioning device of electric vehicles (EV) that do not have a fuel combustion system of an internal combustion engine or the like for heat supply, or vehicles in which the amount of heat of the fuel combustion system serving as a heat source is small, an air conditioning device that uses a heat pump (refrigerant circuit) for heat supply is known.The air conditioning device using a heat pump causes an external heat exchanger to function as a heat sink during the heating operation, and thus acquires a heating heat supply from the outside air. At an extremely low outside air temperature, heat absorption from the outside air becomes difficult, and hence the heating power is greatly lowered. On the other hand, when the heat supply is ensured using an electric heater such as a PTC heater or the like, the power consumption of the battery increases greatly, which may adversely affect the range in the case of electrically driven vehicles and the like, and increases the manufacturing cost of the air conditioning device due to the incorporation of the PTC heater.Hot gas heating using high temperature and high pressure refrigerant discharged from a compressor of the refrigerant circuit is a heating form without heat absorption and thus a heating form expected to be effective even in an extremely low temperature environment. In hot gas heating, an internal heat exchanger of the vehicle air conditioning apparatus serves as a heat sink (internal condenser) to which the high-temperature and high-pressure refrigerant discharged from the compressor is directly supplied, and the refrigerant discharged from the heat sink is returned to the compressor not via an external heat exchanger but via an accumulator (see Patent Document 1 below).LIST OF REFERENCES DOCUMENTSPATENT DOCUMENTPatent Document 1: JP 2014-196017 ASUMMARY OF THE INVENTIONOBJECT OF THE INVENTIONA vehicle air conditioning device capable of performing hot gas heating performs hot gas heating by switching between a refrigerant flow path on which hot gas heating is performed and a refrigerant flow path on which regular heat absorption heating is performed, in situations where heat absorption from the outside air, etc. is not possible, hot gas heating, and in situations where heat absorption from the outside air, etc. is possible, heat absorption heating.At this time, during hot gas heating, refrigerant flow path switching is performed so as not to flow refrigerant to an external heat exchanger provided for heat absorption heating, but if frost formation occurs at the external heat exchanger in situations of extremely low outside air temperature, there is a problem that switching from hot gas heating to heat absorption heating is not possible, system efficiency of which is improved.As a related art for a defrosting operation in which no heat absorption is performed, defrosting is generally known in which refrigerant of high temperature and reduced pressure is directly supplied to the external heat exchanger without refrigerant discharged from the compressor discharging heat at the internal heat exchanger, but there is a problem that defrosting of the external heat exchanger cannot be performed during execution of the hot gas heating operation because the refrigerant of high temperature and reduced pressure is directly supplied to the external heat exchanger. In the related art, moreover, defrosting is performed with low-pressure gaseous refrigerant, and there is a problem that efficient defrosting is not possible.It is an object of the present invention to counteract these problems. Thus, among other things, the present invention has as its object to enable, by performing defrosting of the external heat exchanger during execution of the hot gas heating operation, switching from hot gas heating to heat receiving heating, the system efficiency of which is improved, and by utilizing refrigerant of high pressure, to perform defrosting of the external heat exchanger with high efficiency.SOLUTION OF THE OBJECTSTo achieve these objects, the present invention is provided with the following configuration.A vehicle air conditioning apparatus comprising a refrigerant circuit having a compressor, an internal heat exchange portion and an external heat exchange portion, an air conditioning unit inside which the internal heat exchange portion is disposed, and a control device that controls the refrigerant circuit and the air conditioning unit, wherein the refrigerant circuit has a hot gas bypass that reduces at least a part of the refrigerant compressed in the compressor in pressure and returns it to the compressor without passing through the internal heat exchange portion and the external heat exchange portion, wherein the control device can selectively execute a hot gas heating operation in which the refrigerant in the external heat exchange portion does not receive heat and a part of the refrigerant compressed in the compressor in the internal heat exchange portion releases heat to heat a passenger compartment, and a heat receiving heating operation in which the refrigerant in the external heat exchange portion receives heat, wherein, during execution of the hot gas heating operation, defrosting of the external heat exchange portion is performed by flowing refrigerant having passed through the internal heat exchange portion to the external heat exchange portion.EFFECTS OF THE INVENTIONAccording to the present invention having these features, by performing defrosting of the external heat exchanger during execution of the hot gas heating operation, switching from the hot gas heating to the heat receiving heating, the system efficiency of which is better, can be enabled, and by using refrigerant of high pressure, defrosting of the external heat exchanger can be performed with high efficiency.BRIEF DESCRIPTION OF THE DRAWINGSFIG. 1 is a schematic explanatory view of a system configuration example of a vehicle air conditioning apparatus of an embodiment of the present invention. FIG. 2 is an explanatory view of a control device of the vehicle air conditioning device of the embodiment of the present invention. FIG. 3 is an explanatory view of the operation of a refrigerant circuit in the hot gas heating operation of the vehicle air conditioning apparatus of the embodiment of the present invention. FIG. 4 is an explanatory view of the operation of the refrigerant circuit in the heat receiving heating operation of the vehicle air conditioning device of the embodiment of the present invention. FIG. 5 is an explanatory view of the operation of a refrigerant circuit while performing hot gas heating operation and defrosting. FIG. 6 is a view explaining the basic operation of the vehicle air conditioning device of the embodiment of the present invention. FIG. 7 is an explanatory view of an operation flow including a defrosting operation. FIG. 8 is an explanatory view of a configuration example of the control device of an electric vehicle (EV) including the vehicle air conditioning device.DESCRIPTION OF THE EMBODIMENTSHereinafter, an embodiment of the present invention will be described with reference to the figures. In the following description, like reference numerals in the different figures refer to parts having the same function, and repeated description thereof for the individual figures is omitted for simplicity. The bold lines in the refrigerant circuit 10 in the figures indicate the refrigerant flow path on which the refrigerant flows, where the black bold lines indicate the flow of high-pressure refrigerant and the gray bold lines indicate the flow of low-pressure refrigerant. The broken lines of the refrigerant circuit 10 indicate flow paths in which no refrigerant flows.System ConfigurationFIG. 1 schematically shows a configuration example of a vehicle air-conditioning device 1 of an embodiment of the present invention. This configuration example is exemplary and is not limited to a concrete configuration.The vehicle air conditioning device 1 includes a refrigerant circuit 10 and an air conditioning unit 20, and the refrigerant circuit 10 includes a compressor 2, internal heat exchangers 21, 22 provided inside the air conditioning unit 20, and an external heat exchanger 11 provided outside the passenger compartment, being arranged along a refrigerant flow path. The internal heat exchangers 21, 22 are provided for heat exchange with air flowing in the air conditioning unit 20, and the external heat exchanger 11 is provided for heat exchange between outside air outside the passenger compartment and the refrigerant.The compressor 2 of the refrigerant circuit 10 compresses and circulates the refrigerant. The refrigerant compressed at the compressor 2 is reduced to the required pressure on an as-needed selected refrigerant flow path by passing through a first pressure-reducing portion V 1, a second pressure-reducing portion V 2, a third pressure-reducing portion V 3, and a fourth pressure-reducing portion V 4, which are expansion valves, for example. Flow path switching valves 12, 13 for switching the refrigerant flow path are provided on the refrigerant circuit 10, and check valves 14, 15 are provided as needed to regulate the flow direction of the refrigerant. Provided directly upstream of the compressor 2 in the refrigerant circuit 10 is an accumulator 16 which receives liquid refrigerant and carries out a gas-liquid separation on the refrigerant.As mentioned above, the air conditioning unit 20 includes the internal heat exchangers 21, 22 inside thereof, and air introduced from inside or outside the passenger compartment by a fan 23 selectively flows through the internal heat exchangers 21, 22 and is blown into the passenger compartment. A ventilation door 24 is provided on the air conditioning unit 20. When the illustrated louver 24 is fully opened, the air introduced by the fan 23 is blown into the passenger compartment while passing through the two internal heat exchangers 21, 22, and when the louver 24 is fully closed, the air introduced by the fan 23 is blown into the passenger compartment while passing through only the internal heat exchanger 22. Another louver 25 provided on the air conditioning unit 20 serves to switch the air introduced from the fan 23 between air from inside and outside the passenger compartment, and selectively closes an air introduction port 25A communicated with the passenger compartment exterior and an air introduction port 25B communicated with the passenger compartment interior.It is described as an example that direct heat exchange between the refrigerant and the air occurs at the external heat exchanger 11 and the internal heat exchangers 21, 22, but the heat exchange between the refrigerant and the air may also occur via a heat carrier that performs heat exchange with the refrigerant. Thus, a configuration is possible in which the refrigerant receives the heat from the air via a heat carrier and the heat of the refrigerant is released to the air via a heat carrier.The vehicle air conditioning device 1 includes a heat transfer medium circuit 30 as needed. the heat transfer medium circuit 30 circulates a heat transfer medium by a circulation pump 31, heats the heat transfer medium by an electric coolant heater (ECH) 32, and performs waste heat recovery on a temperature regulating object such as a battery or the like by a temperature regulating object heat exchanger 33. Provided on the refrigerant circuit 10 and the heat transfer medium circuit 30 is a refrigerant-heat transfer medium heat exchanger 34 that performs heat exchange between the refrigerant and the heat transfer medium by means of a flow path 34A in which the refrigerant flows and a flow path 34B in which the heat transfer medium flows.Control DeviceAs shown in FIG. 2, the vehicle air conditioning device 1 includes a control device 100. The control device 100 controls the refrigerant circuit 10, the air conditioning unit 20, and the heat transfer medium circuit 30 as needed, based on various input signals (air conditioning command signals, charger connection signals, and the like) and detection signals from a sensor unit 40.The sensor unit 40 that feeds detection signals to the control device 100 includes, among other things, an outside air sensor 41 that detects the state of the outside air such as outside air temperature, outside air humidity, etc., a compressor current sensor 42 for detecting the power consumption (power 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 whether an occupant is present in the passenger compartment, and a blowing air temperature sensor 46 that detects the blowing air temperature of the air conditioning unit 20. These sensors are examples. The sensor unit 40 is equipped with various sensors for acquiring the information necessary for the various controls of the control device 100.The control objects of the control device 100 in the refrigerant circuit 10 are, among other things, the compressor 2, the first pressure reducing portion V 1, the second pressure reducing portion V 2, the third pressure reducing portion V 3, the fourth pressure reducing portion V 4, in the air conditioning unit 20, among other things, the fan 23 and the louvers 24, 25, and in the heat transfer medium circuit 30, among other things, the circulation pump 31. Also, the control device 100 controls, based on the processing results of the control device 100, the vehicle air conditioning device 1 or a notification device 3 of the vehicle (for example, a display device such as a pointer or a monitor, or a voice generation device such as an audio device).Hot Gas Heating ModeIn the hot gas heating operation, the refrigerant does not absorb heat in the external heat exchanger 11, and a part or all of the refrigerant compressed in the compressor 2 dissipates heat in the internal heat exchanger 21 to heat a passenger compartment.FIG. 3 is an explanatory view of the operation of the refrigerant circuit 10 in the hot gas heating operation (including a preparatory operation). In this operation, a part of the high-temperature and high-pressure refrigerant discharged from the compressor 2 passes through the internal heat exchanger 21 and the flow path switching valve 12, undergoes pressure reduction at the third pressure reducing portion V 3, passes through the refrigerant-heat transfer medium heat exchanger 34, undergoes gas-liquid separation at the accumulator 16, and returns to the compressor 2. At this time, in the refrigerant circuit 10, by the first pressure reducing portion V 1 being fully closed, no refrigerant flows to the external heat exchanger 11, and the fourth pressure reducing portion V 4 is also fully closed, so that no refrigerant flows to the internal heat exchanger 22.The refrigerant circuit 10 includes a hot gas bypass 10V that pressurizes and returns at least a part of the refrigerant compressed in the compressor 2 to the compressor 2 without passing through the internal heat exchanger 21 and the external heat exchanger 11. At the hot gas bypass 10V, a part of the high-temperature and high-pressure refrigerant is branched at a branch point P 1 straight downstream of the compressor 2, undergoes pressure reduction at the second pressure reducing portion V 2 (hot gas valve), and merges with low-pressure refrigerant whose pressure has been reduced at the third pressure reducing portion V 3 at a merging point P 2 straight upstream of the accumulator 16.By providing such a hot gas bypass 10V, gaseous refrigerant that has passed through the hot gas bypass 10V is mixed with the liquid refrigerant condensed by the heat emission at the internal heat exchanger 21, so that gas-rich refrigerant can be returned to the compressor 2. In addition, by increasing the amount of refrigerant flowing through the hot gas bypass 10V, the amount of heat discharged at the internal heat exchanger 21 can be suppressed, and therefore, by adjusting the amount of refrigerant flowing in the hot gas bypass 10V by opening and closing the second pressure reducing portion V 2 (hot gas valve), the balance between the heat release amount of the refrigerant circuit 10 and the heat absorption in the compressor 2 can be maintained.Since pressure reduction occurs at the third pressure reduction portion V 3 when the refrigerant flows during the hot gas heating operation in the flow path passing through the internal heat exchanger 21, the refrigerant upstream thereof is high pressure and the refrigerant downstream thereof is low pressure. In order to maintain the heating power, it is important that no heat exchange takes place at the refrigerant-heat transfer medium heat exchanger 34 in the flow path on the low-pressure side. Then, at the air conditioning unit 20, the air introduced by the fan 23 is heated by the heat output from the internal heat exchanger 21 and blown into the passenger compartment.Preparatory OperationIn the preparatory operation performed at the start of the hot gas heating operation, the refrigerant circulates in the refrigerant circuit 10, and no heat emission is performed or restricted in the internal heat exchanger 21 until a certain state of the refrigerant is reached. As one method, the refrigerant circuit 10 is operated in the hot gas heating operation described above while the fan 23 of the air conditioning unit 20 is stopped or restricted. As another method, the refrigerant circuit 10 is operated in the hot gas heating operation described above while the fan 23 of the air conditioning unit 20 is operated, the ventilation door 24 is fully closed, and no blowing air flows to the internal heat exchanger 21.In the former method, since the blowing air from the air conditioning unit 20 is stopped or restricted, it is necessary to notify the occupant that the preparatory operation is currently being performed. In the latter method, on the other hand, first, blown air flows from the air conditioning unit 20 that does not pass through the internal heat exchanger 21, and the occupant can regulate the blown air amount of this blown air, so that the annoying feeling of the occupant is eliminated.Heat Absorbing Heating OperationFIG. 4 is an explanatory view of the operation of the refrigerant circuit 10 in the heat receiving heating operation. In the refrigerant circuit 10, in the heat receiving heating operation, the second pressure reducing portion V 2, the third pressure reducing portion V 3, the fourth pressure reducing portion V 4, and the flow path switching valve 12 are respectively fully closed.In the heat receiving heating operation, the high temperature and high pressure refrigerant discharged from the compressor 2 passes through the internal heat exchanger 21 in the air conditioning unit 20 and undergoes pressure reduction at the first pressure reducing portion V 1, whereupon low pressure refrigerant passes through the external heat exchanger 11 and is returned 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 that has leaked from the compressor 2 condenses in the internal heat exchanger 21 and dissipates heat, and becomes low-pressure refrigerant by the pressure reduction at the first pressure reduction portion V 1, absorbs heat at the external heat exchanger 11, and evaporates, and then returns to the compressor 2. Then, at the air conditioning unit 20, the air introduced by the fan 23 is heated by the heat output from the internal heat exchanger 21 and blown into the passenger compartment.Simultaneous Operation of Hot Gas Heating Operation and Defrosting OperationFIG. 5 illustrates the operation of the refrigerant circuit 10 while performing the hot gas heating operation and a defrosting operation of the external heat exchanger 11, and in the refrigerant circuit 10, in the hot gas heating operation shown in FIG. 3, refrigerant discharged from the compressor 2 and having passed through the internal heat exchanger 21 flows into the external heat exchanger 11 by opening the first pressure reducing portion V 1.In this operation, since the refrigerant from the compressor 2 is high-temperature, high-pressure refrigerant upstream of the third pressure reducing portion V 3 and low-pressure refrigerant downstream of the third pressure reducing portion V 3, defrosting of the external heat exchanger 11 can be performed with high efficiency before the pressure reduction. The high-temperature, high-pressure gaseous refrigerant from the compressor 2 gives heat when passing through the internal heat exchanger 21 and therefore partially condenses, so that the refrigerant in a mixed state of liquid and gaseous flows into the external heat exchanger 11, and therefore efficient defrosting can be performed even in comparison with the conventional hot gas defrosting in which the gaseous refrigerant directly flows into the external heat exchanger 11.In this operation, since the switching between the hot gas heating operation and the hot gas heating operation supplemented by the defrosting operation of the external heat exchanger 11 can be performed by only opening and closing the first pressure reducing portion V 1, the defrosting operation during the hot gas heating operation can be performed quickly at the required timing.By stopping blowing of air to the external heat exchanger 11 (by stopping a blower not shown or closing a shutter not shown) at the external heat exchanger 11 during performing the defrosting operation of the external heat exchanger 11, heat is suppressed from being discharged to the outside air. Thus, defrosting can be performed efficiently, and at the same time, heat dissipation at the internal heat exchanger 21 is given priority, so that heating performance in hot gas heating operation can be ensured. Also, by regulating the first pressure reducing portion V 1 and the second pressure reducing portion V 2 (hot gas valve), it is possible to switch between a defrosting priority operation state and a heating priority operation state as appropriate.By thus performing defrosting of the external heat exchanger 11 during the hot gas heating operation, after the end of the hot gas heating operation, heat absorbing heating can be quickly switched to by absorbing heat from the external heat exchanger 11.Basic OperationThe basic operation of the vehicle air conditioning device 1 by the control device 100 will be described with reference to FIG. 6. When the operation of the vehicle air conditioning apparatus 1 starts, it enters a signal waiting state in which it waits for an air conditioning command signal (step S 01), and when a heating command is now input (step S 01: YES), a transition is made to the next step S 02, while when a command other than a heating command (for example, a cooling command) is input (step S 01: NO), a transition is made to another air conditioning control according to this command (step S 01A).In the next step S02, a judgment is made as to whether the hot gas heating operation is to be performed. Since the hot gas heating operation is performed in a situation where heat absorption heating is not possible practically, for example, in the case where an extremely low temperature situation is detected by the outside air sensor 41, and therefore it is judged that the hot gas heating operation is to be performed (step S 02: YES), a transition is made to the next step S 03. When it is judged in step S 02 that no hot gas heating operation is performed (step S 02: NO), the above-described air intake heating operation is performed (step S 11).In step S 03, whether refrigerant condensed at, for example, the external heat exchanger 11 or the refrigerant-heat transfer medium heat exchanger 34 in the refrigerant circuit 10 has accumulated is judged from, for example, the state of the refrigerant in the refrigerant circuit 10 or the situation of the heating operation before the start, and when it is judged that refrigerant has accumulated and refrigerant recovery is required (step S 03: YES), refrigerant recovery processing is performed (step S 04). When it is judged in step S 03 that no refrigerant recovery is required (step S 03: NO), the refrigerant recovery processing (step S 04) is skipped. When refrigerant recovery processing is performed after the heating end in steps S 09, S 10, steps S 03, S 04 may be omitted here.In step S 05, the above-described preparation operation performed at the start of the hot gas heating operation is performed. In the preparation operation, the operation of the refrigerant circuit 10 in the hot gas heating operation is performed in a state where no heat release from the refrigerant circuit 10 occurs or is restricted, so that the circulating refrigerant comes into a high pressure state and energy is stored in the refrigerant. In the preparation operation (step S 05), as mentioned above, the fan 23 of the air conditioning unit 20 is stopped.Until it is judged in step S 06 that the refrigerant state suitable for performing the hot gas heating operation is reached, the preparation operation (step S 05) is continued (step S 06: NO), and meanwhile, processing for informing the occupant is performed so that the occupant of the passenger compartment does not feel a concern for equipment trouble or discomfort because no blowing air is blown out from the air conditioning unit 20 (step S 06A).In the notification to the occupant (occupant notification: step S 06A), output from the control device 100 to the notification device 3 is performed, and the occupant is informed that the above-described preparation operation is currently being performed. As an example, a display device of the vehicle such as a display element or a monitor displays a blink or a monitor display. As another example, the occupant is informed that the above-described preparation operation is currently being performed by generating a voice message or a notification sound from a speaker of the vehicle. In this way, it can be communicated to the occupant that the situation that no blowing air is currently being blown out is not due to a device fault, but rather to the regular preparatory operation of the hot gas heating operation.When it is determined that sufficient energy has been stored in the refrigerant during the preparatory operation, such as from the detection result of the refrigerant pressure or the detection result of the power consumption of the compressor 2, it is judged that the preparatory operation ends (step S 06: YES), and the hot gas heating operation in which blown air is blown out is executed (step S 07).The hot gas heating operation is executed until a heating end command is input (step S 08: NO), and when the heating end command is input (step S 08: YES), as well as steps S 03, S 04, a refrigerant recovery necessity judgment is made (step S 09), and in the case of the necessity being present, a refrigerant recovery processing is made (step S 10), whereupon the air conditioning operation ends. When steps S 03, S 04 are executed in the next air conditioning process, steps S 09, S 10 may be omitted.When the heat receiving heating operation is performed in step S 11, it is continued until a subsequent heating end command (step S 12: NO), and when the heating end command is output (step S 12: YES), the necessity of refrigerant recovery is judged (step S 09), and in the case of the presence of the necessity, refrigerant recovery processing is performed (step S 10), whereupon the air conditioning process ends.Operation of Defrosting Operation during Hot Gas Heating OperationFIG. 7 is an explanatory view of a subordinate flow of the hot gas heating operation. When step S 07 starts, it is judged whether defrosting of the external heat exchanger 11 is required (step S 07A). This judgment may be made from the outside air temperature or by detecting whether frost adheres to the external heat exchanger 11. When defrosting of the external heat exchanger 11 is not required (step S 07A: NO), the hot gas heating operation is performed in the refrigerant circuit 10 of FIG. 3.When it is judged that defrosting of the external heat exchanger 11 is required (step S 07A: YES), the first pressure reducing portion V 1 is opened (step S 07B), and refrigerant of high temperature and high pressure flows into the external heat exchanger 11 until the end of defrosting (step S 07C: NO), thus performing the hot gas heating operation and the defrosting operation simultaneously. When the defrosting ends (step S 07C: YES), the first pressure reducing portion V 1 is closed (step S 07D), and the hot gas heating operation alone is returned.Configuration of Control Device in Electric Vehicle (EV)As shown in FIG. 8, the control device 100 of the vehicle air conditioning device 1 is configured as an electronic control unit (ECU) connected via an on-board network L to various ECUs that control the electric vehicle (EV). The control device 100 includes a central processing unit (CPU) 101, read only memory (ROM) 102, random access memory (RAM) 103, an input / output interface (I / F) 104, an internal communication interface (I / F) 105, and the like, and the respective hardware elements are connected to each other via a bus 106.The CPU 101 executes the controls of the control device 100 by executing programs stored in the ROM 102. The ROM 102 is a nonvolatile memory. In the ROM 102, for example, programs executed by the CPU 101 and the data and the like required for executing the programs by the CPU 101 are stored. The RAM 103 is a main storage device such as a DRAM (Dynamic Random Access Memory) or an SRAM (Static Random Access Memory). The RAM 103 functions as a work area that the CPU 101 uses in executing the programs. The input / output I / F 104 is connected to various sensors and monitors installed in the EV, and inputs data to the CPU 101, and outputs data from the calculation processing of the CPU 101. By connecting the internal communication I / F 105 to the on-board network L, transmission and reception of data are controlled with the other ECUs installed in the EV.By inputting, to the control device 100, through the input / output I / F 104 and the internal communication I / F 105, data on environmental information for the environment or data on the operating state of the EV, the control of the vehicle air conditioning device 1 is executed by the programs executed by the CPU 101.A battery B is installed in the EV. The battery B is charged by connecting a connector PS of a charger to a battery terminal BP, and the vehicle air conditioning device 1 is supplied with electric power via the battery B. The state of connection of the connector PS to the battery terminal BP is transmitted to the control device 100 as a charger connection signal via the on-board network L.Although an embodiment of the present invention has been described in detail above with reference to the figures, the concrete configurations are not limited to this embodiment, and design changes that do not depart from the gist of the present invention also fall within the scope of the invention. As long as there is no contradiction or problems in terms of purpose, configuration, and the like, the individual techniques of the above embodiment can be mutually transmitted and combined.LIST OF REFERENCE NUMERALS1 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 Accumulator 20 Air conditioning unit 21, 22 Internal heat exchanger 23 Fan 30 Heat transfer medium circuit 31 Circulation pump 32 Heater 33 Temperature regulation object heat exchanger 34 Refrigerant heat transfer medium heat exchanger 24, 25 Louver 25A, 25B Air introduction port 40 Sensor unit 41 Outside air sensor 42 Compressor flow sensor 43 Refrigerant temperature sensor 44 Refrigerant pressure sensor 45 Occupant sensor 46 Blown air temperature sensor 100 Control device V 1 First pressure reduction portion V 2 Second pressure reduction portion V 3 Third pressure reduction portion V 4 Fourth pressure reduction portion

Claims

A vehicle air conditioning apparatus comprising a refrigerant circuit having a compressor, an internal heat exchange portion and an external heat exchange portion, an air conditioning unit inside which the internal heat exchange portion is disposed, and a control device that controls the refrigerant circuit and the air conditioning unit, wherein the refrigerant circuit has a hot gas bypass that reduces at least a part of the refrigerant compressed in the compressor in pressure and returns it to the compressor without passing through the internal heat exchange portion and the external heat exchange portion, wherein the control device can selectively execute a hot gas heating operation in which the refrigerant in the external heat exchange portion does not absorb heat and a part of the refrigerant compressed in the compressor in the internal heat exchange portion absorbs heat to heat a passenger compartment, and a heat absorbing heating operation in which the refrigerant in the external heat exchange portion absorbs heat, wherein, during execution of the hot gas heating operation, defrosting of the external heat exchange portion is performed by flowing refrigerant having passed through the internal heat exchange portion to the external heat exchange portion.The vehicle air-conditioning device according to claim 1, wherein the control device performs pressure reduction of the refrigerant discharged from the external heat exchange portion and returns it to the compressor.The vehicle air-conditioning apparatus according to claim 1, wherein the refrigerant circuit includes flow path switching means that switches between a bypass flow path on which the refrigerant discharged from the internal heat exchanger bypasses the external heat exchanger and a refrigerant flow path on which refrigerant flows to the bypass flow path and the external heat exchanger, wherein when defrosting of the external heat exchanger portion is performed during the hot gas heating operation, the bypass flow path is closed by the flow path switching means and refrigerant flows to the external heat exchanger portion.The vehicle air-conditioning device according to claim 1, comprising a shutter grill that restricts inflow of air into a flow path of air that performs heat exchange with the external heat exchange portion, wherein the shutter grill is closed when performing defrosting of the external heat exchange portion.

Images