Air conditioner for vehicle

Abstract

To provide an air conditioner for a vehicle which improves safety.SOLUTION: An air conditioner for a vehicle includes: refrigerant circuits (10 and 110) which are arranged on a front room (FR) of a vehicle (V) and circulate a combustible refrigerant therein; and a storage container (100) for storing the refrigerant circuits (10 and 110) in a storage container internal space (100a). The storage space internal space (100a) is filled with predetermined gas containing no combustible component, and is sealed at pressure higher than that of the front room (FR).SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a vehicle air conditioner including a refrigerant circuit in which a flammable refrigerant circulates.

Background Art

[0002] Many vehicles such as passenger cars are provided with a vehicle air conditioner including a refrigerant circuit for conditioning the temperature of a passenger compartment in which passengers board. The prior art related to vehicle air conditioners is disclosed in Patent Document 1.

[0003] The vehicle air conditioner disclosed in Patent Document 1 includes a refrigerant circuit (primary loop), a heat medium circuit (secondary loop) thermally coupled to the refrigerant circuit via a heat exchanger, and an air conditioning heat exchanger that is part of the heat medium circuit and can condition the temperature of the passenger compartment, and is capable of conditioning the temperature of the passenger compartment in which passengers board.

[0004] It is said that a known appropriate single refrigerant or mixed refrigerant can be used as the refrigerant used in the refrigerant circuit, and HFC (Hydro Fluoro Carbon) and HFO (Hydro Fluoro Olefin) refrigerants that are chlorofluorocarbon refrigerants, hydrocarbon refrigerants (Hydro Carbon) such as propane and isobutane, and carbon dioxide are shown.

[0005] Here, from the viewpoint of reducing the environmental load, reduction of the use of chlorofluorocarbon refrigerants whose ozone layer depletion has been pointed out is required. Further, in a refrigerant circuit using carbon dioxide as a refrigerant, the high pressure during operation of the refrigerant circuit is a problem. In this regard, hydrocarbon refrigerants have the advantage of having a small environmental load and having no significant difference in the pressure of the refrigerant circuit from that of chlorofluorocarbon refrigerants with a large amount of usage experience.

[0006] On the one hand, hydrocarbon-based refrigerants generally have a higher degree of flammability than chlorofluorocarbon-based refrigerants. Refrigerants with a high degree of flammability are sometimes called flammable refrigerants. As a precaution in case the flammable refrigerant filled in the refrigerant circuit leaks unintentionally, there is a measure to dispose the refrigerant circuit inside a sealed container in advance. This can prevent the flammable refrigerant from diffusing into the surroundings or encountering an ignition source even if it leaks, thereby enhancing safety.

Prior Art Documents

Patent Documents

[0007]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0008] In addition to sealing the refrigerant circuit using a flammable refrigerant with a sealed container, further improvement in safety is required. The present invention aims to provide a vehicle air conditioner with improved safety.

Means for Solving the Problems

[0009] In the following description, for ease of understanding of the present invention, reference numerals in the accompanying drawings are appended in parentheses, but the present invention is not limited to the illustrated forms thereby.

[0010] According to the present invention, there is provided a vehicle air conditioner mounted on a vehicle (V) having a passenger compartment (CR) and a front compartment (FR) located in front of the passenger compartment (CR), a refrigerant circuit (10, 110) disposed in the front compartment (FR) and through which a flammable refrigerant circulates inside, a cooling liquid circuit (50) through which a liquid heat medium circulates inside and absorbs heat from the air supplied to the passenger compartment (CR) by an air cooler (52), a heat dissipation liquid circuit (80) through which a liquid heat medium circulates inside and dissipates heat to the air taken into the front compartment (FR) by a heat dissipation heat exchanger (82), A storage container (100) having an internal space (100a) formed therein, comprises The refrigerant circuit (10, 110) and the liquid cooling circuit (50) are thermally coupled via a water-cooled refrigerant heat exchanger (15), The refrigerant circuit (10, 110) and the liquid heat dissipation circuit (80) are thermally coupled via a water-cooled refrigerant heat exchanger (13), The refrigerant circuit (10, 110) is stored in the internal space (100a) of the storage container, The internal space (100a) of the storage container is filled with a predetermined gas containing no combustible components and sealed at a pressure higher than that of the front chamber (FR), and a vehicle air conditioner is provided.

Advantages of the Invention

[0011] The present invention can provide a vehicle air conditioner with improved safety.

Brief Description of the Drawings

[0012]

Figure 1

Figure 2A

Figure 2B

Figure 3

Modes for Carrying Out the Invention

[0013] Embodiments will be described based on the accompanying drawings. In the drawings, Fr indicates front, Rr indicates rear, Le indicates left, Ri indicates right, Up indicates up, and Dn indicates down.

[0014] <Embodiment 1> Refer to FIG. 1. The vehicle air conditioner is mounted on vehicle V, conditions the outside air and the inside air, and adjusts the temperature of the passenger compartment CR. The vehicle air conditioner includes a refrigerant circuit 10 in which a flammable refrigerant circulates, a heat dissipation liquid circuit 80 in which a liquid heat medium circulates, a cooling liquid circuit 50 in which a liquid heat medium circulates, and a storage container 100 having an internal storage container internal space 100a formed therein. In FIG. 1, the arrows shown in the refrigerant circuit 10, the heat dissipation liquid circuit 80, and the cooling liquid circuit 50 indicate the flow directions of the refrigerant or the heat medium when each circuit is operated.

[0015] (Vehicle) Vehicle V has a passenger compartment CR in which passengers board, and a front compartment FR that is partitioned from the passenger compartment CR by a dash panel VD and is located in front of the passenger compartment CR. Near the foremost part of the front compartment FR, a front compartment air intake VW capable of introducing the air in front of vehicle V into the front compartment FR is formed.

[0016] (Refrigerant Circuit) The refrigerant circuit 10 is configured such that a flammable refrigerant circulates therein. More specifically, the refrigerant circuit 10 is configured to connect a compressor 11, a heat dissipation water-refrigerant heat exchanger 13, a cooling expansion device 14, a cooling water-refrigerant heat exchanger 15, and the compressor 11 again by piping, and the refrigerant circulates by flowing in this order. Although not shown, pipes attached to the refrigerant discharge port of the compressor 11 and the suction port of the compressor 11 are well-known rubber hoses in order to attenuate the amount of vibration transmitted from the compressor 11 to the connected components. In this embodiment, a refrigerant storage portion 16 for storing surplus refrigerant is disposed between the cooling water-refrigerant heat exchanger 15 and the compressor 11. In this case, the refrigerant storage portion 16 functions as a so-called accumulator, separates the gaseous-phase refrigerant and the liquid-phase refrigerant, stores the liquid-phase refrigerant, and allows only the gaseous-phase refrigerant to flow out. Further, although not shown, the refrigerant storage portion 16 may be disposed between the heat dissipation water-refrigerant heat exchanger 13 and the cooling expansion device 14. In this case, the refrigerant storage portion 16 functions as a so-called liquid tank, separates the gaseous-phase refrigerant and the liquid-phase refrigerant, and allows a part of the liquid-phase refrigerant to flow out.

[0017] (Refrigerant) In this embodiment, a refrigerant with a relatively small ozone depletion potential and a relatively low pressure during the operation of the refrigerant circuit 10 is selected. Specifically, hydrocarbons such as propane, propylene, and isobutane, and ammonia are used. These refrigerants have a significantly smaller ozone depletion potential than the chlorofluorocarbon refrigerant R134a and can be operated at a significantly lower pressure than when carbon dioxide is used as the refrigerant. On the other hand, when mixed with oxygen or a gas containing oxygen, high flammability is exhibited depending on the mixing concentration range. Note that propane and isobutane are less irritating than ammonia and are preferable.

[0018] (Compressor) The compressor 11 sucks in the refrigerant of the refrigerant circuit 10, compresses it, and then discharges it. The compressor 11 in this embodiment is an electric compressor. The compressor 11 includes a compression mechanism, a motor that drives this compression mechanism, and an inverter that controls this motor. The inverter is electrically connected to a control unit 100z described later and drives the motor based on a signal sent from the control unit 100z. The refrigerant discharged from the compressor 11 flows into the heat exchanger for heat rejection using water as the refrigerant 13 in a high-temperature and high-pressure state.

[0019] (Heat exchanger for heat rejection using water as the refrigerant) The heat exchanger for heat rejection using water as the refrigerant 13 exchanges heat without the high-temperature and high-pressure refrigerant discharged from the compressor 11 coming into contact with the liquid heat medium circulating in the heat rejection liquid circuit 80, and transfers the heat of the refrigerant circuit 10 to the heat rejection liquid circuit 80. As a result, the refrigerant passing through there has its temperature decreased while remaining at a high pressure, and the liquid heat medium in the heat rejection liquid circuit 80 has its temperature increased. The heat exchanger for heat rejection using water as the refrigerant 13 uses a heat exchanger with a well-known structure, and materials such as aluminum alloy and copper alloy are used for it. The refrigerant flowing out of the heat exchanger for heat rejection using water as the refrigerant 13 flows into the expansion device for refrigeration 14.

[0020] (Expansion device for refrigeration) The cooling expansion device 14 adiabatically expands the medium-temperature and high-pressure refrigerant flowing out of the heat dissipation water-refrigerant heat exchanger 13 and changes its state to low temperature and low pressure. The cooling expansion device 14 uses an expansion device with a well-known structure. The refrigerant flowing out of the cooling expansion device 14 flows into the cooling water-refrigerant heat exchanger 15. The cooling expansion device 14 may be a mechanical expansion device that autonomously adjusts the valve opening, or an electronically controlled expansion device that adjusts the valve opening according to an external signal.

[0021] (Cooling water-refrigerant heat exchanger) The cooling water-refrigerant heat exchanger 15 exchanges heat with the low-temperature and low-pressure refrigerant flowing out of the cooling expansion device 14 without contacting the liquid heat medium circulating in the cooling liquid circuit 50, and absorbs heat from the cooling liquid circuit 50. As a result, the refrigerant passing through it has its temperature rise while remaining at low pressure, and the liquid heat medium in the cooling liquid circuit 50 has its temperature drop. The cooling water-refrigerant heat exchanger 15 uses a heat exchanger with a well-known structure, and materials such as aluminum alloy and copper alloy are used for it. The refrigerant flowing out of the cooling water-refrigerant heat exchanger 15 is inhaled into the compressor 11 after passing through the refrigerant storage section 16.

[0022] (Heat dissipation liquid circuit) The heat dissipation liquid circuit 80 is configured such that a liquid heat medium circulates inside it. More specifically, the heat dissipation liquid circuit 80 is configured to connect the heat dissipation pump 81, the heat dissipation water-refrigerant heat exchanger 13, the heat dissipation heat exchanger 82, and the heat dissipation pump 81 again by piping, and the liquid heat medium circulates by flowing in this order.

[0023] (Heat medium of the heat dissipation liquid circuit) The liquid heat medium circulating in the heat dissipation liquid circuit 80 is, for example, a mixture obtained by adding a glycol-based solvent and a rust inhibitor to water. Thereby, the occurrence of problems due to freezing and rust can be suppressed.

[0024] (Heat dissipation pump) The heat dissipation pump 81 pumps the liquid heat medium in the heat dissipation liquid circuit 80, and a pump with a well-known structure is used. The heat medium sent from the heat dissipation pump 81 flows into the heat dissipation water-refrigerant heat exchanger 13.

[0025] (Heat dissipation water-refrigerant heat exchanger) The heat dissipation water-refrigerant heat exchanger 13 exchanges heat between the high-temperature and high-pressure refrigerant discharged from the compressor 11 and the liquid heat medium sent from the heat dissipation pump 81 without contact, and the heat of the refrigerant discharged by the compressor 11 is transferred to the heat dissipation liquid circuit 80. The heat medium flowing out of the heat dissipation water-refrigerant heat exchanger 13 becomes high-temperature and flows into the heat dissipation heat exchanger 82.

[0026] (Heat dissipation heat exchanger and cooling fan) The heat dissipation heat exchanger 82 exchanges heat between the high-temperature and liquid heat medium flowing out of the heat dissipation water-refrigerant heat exchanger 13 and the air flowing there without contact, and dissipates the heat of the heat medium in the heat dissipation liquid circuit 80. The heat dissipation heat exchanger 82 may be called a radiator. The air supplied to the heat dissipation heat exchanger 82 passes through the front chamber air intake VW provided at the front part of the vehicle V (the front part of the front chamber FR) and reaches the heat dissipation heat exchanger 82. In order to adjust the heat dissipation capacity of the heat dissipation heat exchanger 82, a cooling fan 83 is provided along the air flow direction and is operated or stopped according to the temperature conditions. The heat medium flowing out of the heat dissipation heat exchanger 82 has its temperature lowered and is sucked by the heat dissipation pump 81. The four white arrows arranged side by side near the cooling fan 83 in FIG. 1 indicate the air flow when the cooling fan 83 is operated.

[0027] The heat dissipation liquid circuit 80 can be said to be a circuit in which a liquid heat medium circulates inside and dissipates heat to the air taken into the front chamber FR by the heat dissipation heat exchanger 82.

[0028] (Cooling liquid circuit) The liquid circuit 50 for cooling is configured such that a liquid heat medium circulates inside. More specifically, the liquid circuit 50 for cooling is configured to connect a cooling pump 51, a cooling water-refrigerant heat exchanger 15, an air cooler 52, and the cooling pump 51 again by piping, and the liquid heat medium circulates by flowing in this order.

[0029] (Heat medium of the liquid circuit for cooling) As the liquid heat medium circulating in the liquid circuit 50 for cooling, for example, a mixture in which a glycol-based solvent and a rust inhibitor are added to water is used. Thereby, it is possible to suppress the occurrence of problems due to freezing and rust.

[0030] (Cooling pump) The cooling pump 51 pumps the liquid heat medium in the liquid circuit 50 for cooling, and a pump with a well-known structure is used. The heat medium sent from the cooling pump 51 flows into the cooling water-refrigerant heat exchanger 15.

[0031] (Cooling water-refrigerant heat exchanger) The cooling water-refrigerant heat exchanger 15 exchanges heat between the low-temperature and low-pressure refrigerant flowing out of the cooling expansion device 14 and the liquid heat medium sent from the cooling pump 51 without contact, and the heat absorbed by the air cooler 52 is transferred to the refrigerant circuit 10. The heat medium flowing out of the cooling water-refrigerant heat exchanger 15 becomes low-temperature and flows into the air cooler 52.

[0032] (Air cooler) The air cooler 52 is also a component constituting an air conditioning unit 60 described later. When the cooled liquid heat medium passes through the inside, it absorbs heat from the air passing through there. As a result, the temperature of the heat medium passing through there rises, and the air passing through there is cooled. The air cooler 52 may be called a water cooler or a water core. The air cooler 52 uses a heat exchanger with a well-known structure, and for its material, for example, an aluminum alloy or a copper alloy is used. The heat medium flowing out of the air cooler 52 is sucked by the cooling pump 51.

[0033] The liquid circuit 50 for cooling can be said to be a circuit in which a liquid heat medium circulates inside and absorbs heat from the air supplied to the passenger compartment CR by the air cooler 52.

[0034] (Air conditioning unit) The air conditioning unit 60 is a device that sucks in the air in the passenger compartment CR or the outside air of the vehicle V, conditions the temperature, and then supplies it to the passenger compartment CR. The air conditioning unit 60 of this embodiment is arranged adjacent to the dash panel VD, that is, at the front end of the passenger compartment CR. The air conditioning unit 60 includes an air conditioning case 61 in which a blower space 61a is formed inside, a blower device 62 that blows air into the blower space 61a, an air cooler 52 that is arranged in the blower space 61a and can cool the blown air, an air heater 72 that can heat the air flowing out of the air cooler 52, and a mix door 63 that adjusts the ratio of the air flowing into the air heater 72 and the bypassing air. The temperature-conditioned air becomes conditioned air and is supplied to the passenger compartment CR via a plurality of air outlets 64, 65, 66 provided in the air conditioning case 61. The white arrows shown in the passenger compartment CR in FIG. 1 indicate the air flow when the air conditioning unit 60 is operated.

[0035] (Liquid circuit for heating) The vehicle air conditioning apparatus of this embodiment may include a liquid circuit 70 for heating. The liquid circuit 70 for heating is configured such that a liquid heat medium circulates inside. More specifically, the liquid circuit 70 for heating is configured to connect a heating pump 71, a heat source unit HS, an air heater 72, and the heating pump 71 again by piping, and the liquid heat medium circulates by flowing in this order. The liquid circuit 70 for heating of this embodiment is not coupled to the refrigerant circuit 10. The arrow shown in the liquid circuit 70 for heating in FIG. 1 indicates the flow direction of the heat medium when the liquid circuit 70 for heating is operated.

[0036] (Heat medium of the liquid circuit for heating) As the liquid heat medium circulating in the liquid circuit 70 for heating, for example, a mixture obtained by adding a glycol-based solvent and a rust inhibitor to water is used. Thereby, it is possible to suppress the occurrence of problems due to freezing and rust.

[0037] (Heating pump) The heating pump 71 pumps the liquid heat medium in the heating liquid circuit 70, and a pump with a well-known structure is used. The heat medium sent from the heating pump 71 flows into the heat source unit HS.

[0038] (Heat source unit) The heat source unit HS heats the liquid heat medium sent from the heating pump 71. The heat source unit HS is not particularly limited as long as it can supply the amount of heat required by the air conditioning unit 60. For example, an electric heating type hot water generator, a power internal combustion engine for driving the vehicle V, a power internal combustion engine having a function of generating electric power for driving the vehicle V, a vehicle driving motor, and an inverter for controlling this motor can be mentioned. The heat medium that has passed through the heat source unit HS is heated and flows into the air heater 72.

[0039] (Air heater) The air heater 72 is also a component that constitutes the air conditioning unit 60. When the heated liquid heat medium passes through it, it dissipates heat to the air passing through it. As a result, the temperature of the heat medium passing through it decreases, and the air passing through it is heated. The air heater 72 is sometimes called a hot water heater or a hot water core. The air heater 72 uses a heat exchanger with a well-known structure, and for its material, for example, an aluminum alloy or a copper alloy is used. The heat medium that has flowed out of the air heater 72 is sucked into the heating pump 71.

[0040] The heating liquid circuit 70 can be said to be a circuit in which a liquid heat medium circulates inside and heats the air supplied to the passenger compartment CR by the air heater 72.

[0041] (Cooling operation) The operation during the cooling operation will be described. The compressor 11 is operated, and the refrigerant circulates inside the refrigerant circuit 10. The valve opening degree of the cooling expansion device 14 becomes a throttling state, and the circulating refrigerant is adiabatically expanded. The heat dissipation pump 81 is operated, and the liquid heat medium circulates inside the heat dissipation liquid circuit 80. The cooling pump 51 is operated, and the liquid heat medium circulates inside the cooling liquid circuit 50. The blower 62 is operated, and air is supplied to the air cooler 52 disposed in the blowing space 61a. The position of the mix door 63 is adjusted so that the ratio of the air bypassing the air heater 72 is maximized. The opening degrees of the air outlets 64, 65, and 66 are adjusted respectively and set to blow the conditioned air into the upper space of the passenger compartment CR. Also, the cooling fan 83 is operated to supply the outside air of the vehicle V taken in from the front compartment air intake VW to the heat dissipation heat exchanger 82.

[0042] The heat medium circulating in the cooling liquid circuit 50 is cooled by the cooling water-refrigerant heat exchanger 15, flows into the air cooler 52, and cools the air flowing there. The refrigerant circulating in the refrigerant circuit 10 absorbs heat in the cooling water-refrigerant heat exchanger 15 and dissipates heat in the heat dissipation water-refrigerant heat exchanger 13. The heat medium circulating in the heat dissipation liquid circuit 80 absorbs heat in the heat dissipation water-refrigerant heat exchanger 13, then flows into the heat dissipation heat exchanger 82, and dissipates heat to the air flowing there. As a result, the heat absorbed from the air by the air conditioning unit 60 is transferred to the air taken in from the outside of the vehicle V via the refrigerant circuit 10 and the heat dissipation heat exchanger 82. The air cooled by the air cooler 52 is supplied to the passenger compartment CR without being heated by the air heater 72.

[0043] (Heating operation) The operation during the heating operation will be described. The heating pump 71 is operated, and the liquid heat medium circulates inside the heating liquid circuit 70. The blower 62 is operated, and air is supplied to the blowing space 61a. The position of the mix door 63 is adjusted so that the ratio of the air flowing into the air heater 72 is maximized. The opening degrees of the air outlets 64, 65, and 66 are adjusted respectively and set to blow the conditioned air into the lower space of the passenger compartment CR. Also, when the heat source unit HS is a power internal combustion engine, it is operated. When the heat source unit HS is an electric heating type hot water generator, the electric heating type hot water generator is operated.

[0044] The heat medium circulating in the liquid circuit 70 for heating is heated in the heat source section HS, then flows into the air heater 72, and dissipates heat to the air flowing there. As a result, the heat generated in the heat source section HS is transferred to the air flowing through the air conditioner unit 60 by the air heater 72 and supplied to the passenger compartment CR.

[0045] (Temperature harmonization operation) The operation during the temperature harmonization operation will be described. The compressor 11, the radiator pump 81, the cooling pump 51, and the blower 62 are operated, and the valve opening degree of the cooling expansion device 14 is in a throttled state. The position of the mix door 63 is adjusted so that the respective amounts of air flowing into the air heater 72 and the air bypassing the air heater 72 do not become zero. The opening degrees of the air outlets 64, 65, and 66 are adjusted respectively and set to distribute and blow out the harmonized air to the upper space and the lower space of the passenger compartment CR. Also, the cooling fan 83 is operated to supply the outside air of the vehicle V taken in from the front compartment air intake VW to the radiator heat exchanger 82.

[0046] The heat absorbed from the air by the air conditioner unit 60 is transferred to the outside air by the radiator heat exchanger 82 via the refrigerant circuit 10. A part of the air cooled by the air cooler 52 is heated by the air heater 72, and the remaining part bypasses the air heater 72. The air heated by the air heater 72 and the air bypassing the air heater 72 are mixed to achieve temperature harmonization and supplied to the passenger compartment CR via any one of the air outlets 64, 65, and 66.

[0047] (Storage container) Refer to FIG. 1. The vehicle air conditioner has a storage container 100 in which an internal space 100a of the storage container is formed. The internal space 100a of the storage container stores the refrigerant circuit 10. It can also be said that the refrigerant circuit 10 is stored in the internal space 100a of the storage container. More precisely, in addition to the refrigerant circuit 10, the internal space 100a of the storage container stores a part of the heat dissipation liquid circuit 80 and a part of the cooling liquid circuit 50. The internal space 100a of the storage container and the outside of the storage container 100 are connected via pipes for sending the heat medium to the heat radiation water-refrigerant heat exchanger 13, pipes for sending the heat medium flowing out from the heat radiation water-refrigerant heat exchanger 13 to the heat dissipation heat exchanger 82, pipes for sending the heat medium to the cooling water-refrigerant heat exchanger 15, and pipes for sending the heat medium flowing out from the cooling water-refrigerant heat exchanger 15 to the air cooler 52.

[0048] (Discharge valve) Refer to FIG. 2A. A schematic cross-section of the storage container 100 along the line 2-2 in FIG. 1 is shown. In the internal space 100a of the storage container, a downward protruding space 100au protruding downward is formed on the bottom surface, and a discharge valve 100d is provided at the lowermost part thereof. The discharge valve 100d is electrically connected to a control unit 100z installed outside the storage container 100. The opening degree of the valve is controlled in response to a signal from the control unit 100z.

[0049] (Pressure sensor, gas sensor) Also, a pressure sensor 100b and a gas sensor 100c are arranged in the internal space 100a of the storage container and are electrically connected to a control unit 100z installed outside the storage container 100. The pressure sensor 100b and the gas sensor 100c transmit the detected physical quantity to the control unit 100z.

[0050] (Control unit) Outside the storage container 100, a control unit 100z is arranged. The control unit 100z is provided independently. Alternatively, although not shown, it may be integrally provided in another control unit that controls other vehicle components. The control unit 100z is electrically connected to, in addition to the pressure sensor 100b, the gas sensor 100c, and the discharge valve 100d, the inverter of the compressor 11, the cooling fan 83, the refrigeration pump 51, the heating pump 71, the blower 62, the mix door 63, and the opening and closing doors of the air outlets 64, 65, and 66 (not shown), etc., and controls the vehicle air conditioner.

[0051] (Predetermined gas) The internal space 100a of the storage container is filled with a predetermined gas that does not contain combustible components. The predetermined gas maintains a gaseous state within the operating temperature range of the refrigerant circuit 10. In this embodiment, air is filled.

[0052] (Filling pressure) Here, the internal space 100a of the storage container is filled with a predetermined gas such that the pressure at normal temperature is higher than atmospheric pressure. For example, when the Celsius temperature is 20 degrees, the predetermined gas is filled and sealed so that it is 110 KPa (gauge pressure) or more.

[0053] (Material) The storage container 100 is not particularly limited as long as, regarding the material and structure of the conductive material M, the filled air does not permeate and the filled pressure does not significantly decrease even after the usage period of the vehicle V, it has the strength to hold the compressor 11 and various heat exchangers, and it satisfies the heat resistance within the operating temperature range of the vehicle V. Examples of the conductive material M include metals such as iron and stainless steel, and resin materials R such as fiber-reinforced nylon. The structure is preferably such that the cross-sectional shape is close to circular or elliptical. The pressure resistance can be enhanced.

[0054] The refrigerant circuit 10 is stored in the internal space 100a of the storage container. This internal space 100a of the storage container is filled with a predetermined gas that does not contain flammable components and is sealed so as to have a pressure higher than that of the front chamber FR. Therefore, even if a flammable refrigerant leaks from the refrigerant circuit 10, the flammable refrigerant does not flow out of the storage container 100.

[0055] For a flammable refrigerant to burn or oxidize explosively, it is a condition that the mixed air (mixed gas) of the gas containing oxygen and the flammable refrigerant is at a mixing concentration between the upper limit and the lower limit of the explosion limit mixing ratio and a ignition source encounters here. Here, increasing the pressure of the predetermined gas filled in the internal space 100a of the storage container as in this embodiment to delay the leakage amount of the flammable refrigerant is to delay the time until the leakage continues and the mixed gas reaches the lower limit of the explosion limit mixing ratio, and the safety can be improved.

[0056] Also, in this embodiment, air is selected as the predetermined gas. Air itself is harmless even if inhaled by a human, and the safety as the gas to be filled can be ensured.

[0057] In this embodiment, the internal space 100a of the storage container has a downward protruding space 100au protruding downward, and the storage container 100 is provided with a discharge valve 100d capable of discharging a predetermined gas from the downward protruding space 100au to the outside of the storage container 100. Therefore, when a flammable refrigerant leaks into the internal space 100a of the storage container, the flammable refrigerant can be discharged to the outside of the storage container 100 through the discharge valve 100d in a planned manner, and the safety can be improved.

[0058] Here, a case where the refrigerant circulating in the refrigerant circuit 10 has a molecular weight larger than that of a predetermined gas filled in the internal space 100a of the storage container is defined as combined condition A. When the refrigerant leaks when combined condition A is satisfied, the concentration of the refrigerant tends to be higher toward the lower part of the internal space 100a of the storage container. A combination that satisfies combined condition A is, for example, a case where propane or isobutane is selected as the refrigerant and air is selected as the predetermined gas. In this embodiment, since the discharge valve 100d capable of discharging the predetermined gas from the downward protruding space 100au to the outside of the storage container 100 is provided, the refrigerant staying in the lower part of the internal space 100a of the storage container can be efficiently discharged to the outside of the storage container 100. As shown in FIG. 2A, by discharging the discharged air Ge from the discharge valve 100d arranged at the lower part of the storage container 100, propane and isobutane, which have a molecular weight larger than that of air and are relatively heavy, can be discharged below the storage container 100. That is, even after discharging the discharged air Ge, propane and isobutane are prevented from staying around the storage container 100, and the safety can be enhanced.

[0059] Also, as shown in FIG. 2A, the gas sensor 100c is preferably arranged in the downward protruding space 100au. When combined condition A is satisfied, the concentration of the refrigerant tends to be higher toward the lower part of the internal space 100a of the storage container, and the refrigerant leakage can be efficiently detected.

[0060] <Modification 1> Alternatively, an inert gas with extremely poor flammability may be selected as the gas filling the internal space 100a of the storage container. Specific examples of the inert gas include nitrogen, argon, and carbon dioxide. Even if the refrigerant leaks, there is almost no oxygen in the internal space 100a of the storage container, and the occurrence of a combustion reaction can be suppressed.

[0061] Also, when nitrogen or argon is selected as the predetermined gas and propane or isobutane is selected as the refrigerant, as shown in FIG. 2A, it is preferable to dispose the gas sensor 100c in the downward protruding space 100au. Propane and isobutane have a larger molecular weight and are relatively heavier than nitrogen and argon. That is, the combined condition A is satisfied. When refrigerant leakage occurs, the concentration of the refrigerant becomes higher toward the lower part of the internal space 100a of the storage container. Here, by disposing the gas sensor 100c in the downward protruding space 100au, refrigerant leakage can be efficiently detected.

[0062] <Modification Example 2> Referring to FIG. 2A. So far, the materials constituting the storage container 100 have been described by way of example, such as iron, stainless steel, and a resin material R such as fiber-reinforced nylon. However, it is preferable to use the resin material R. An increase in the weight of the storage container 100 can be suppressed.

[0063] Referring to FIG. 2B. For the material constituting the storage container 100, it is preferable to use a conductive resin material ER for the inner layer 100in facing the internal space 100a of the storage container and a reinforcing resin material SR for the outer layer 100out provided on the outer surface of the inner layer 100in, respectively. By using the conductive resin material ER for the inner layer 100in, local charging of the inner surface of the inner layer 100in facing the internal space 100a of the storage container is suppressed, and unintentional discharge into the internal space 100a of the storage container is prevented. Thereby, even if the refrigerant leaks and fills the internal space 100a of the storage container, the chance of encounter between the mixed gas in which the refrigerant is mixed and the ignition source can be reduced, and the safety can be improved.

[0064] As the conductive resin material ER used for the inner layer 100in of the storage container 100, for example, a conductive polyacetal resin, or a material obtained by mixing metal fibers such as copper, nickel, and iron into a thermoplastic resin as disclosed in JP-A-2001-245418 can be exemplified. As the thermoplastic resin into which the metal fibers are mixed, a single material such as propylene, polyethylene, polystyrene, acrylonitrile-butadiene-styrene resin, polyethylene terephthalate resin, polyamide resin, or a blend material is used.

[0065] As the reinforcing resin material SR used for the outer layer 100out of the storage container 100, a continuous fiber composite base material in which a continuous fiber fabric is impregnated with a thermoplastic resin is used. This continuous fiber composite base material is known by names such as an organosheet. Examples of the fiber material include glass fiber, carbon fiber, and aramid fiber. The strength of the storage container 100 can be improved, the refrigerant circuit 10 can be reliably held, and it can be mounted on the vehicle V. Further, when the pressure of the gas enclosed in the inner space 100a of the storage container is made higher than the pressure in the front chamber FR, expansion of the storage container 100 can be prevented, and the pressure in the inner space 100a of the storage container can be reliably maintained.

[0066] The storage container 100 is preferably formed by an injection molding process, whether it is formed of a single resin material R shown in FIG. 2A or a plurality of layered resin materials R, R shown in FIG. 2B. Although not shown, the storage container 100 is composed of a first case provided with a concave space and a second case that closes the concave space. After the refrigerant circuit 10 is housed in the concave space of the first case, the second case is attached to the first case, or joined using a bonding method such as adhesion with an adhesive or vibration welding. For the attachment of the second case to the first case, fasteners such as bolts and nuts are used, for example. The operation of enclosing a predetermined gas into the inner space 100a of the storage container is performed via an enclosing valve (not shown). The enclosing valve is provided by integral molding during the injection molding of the first case and the second case.

[0067] The discharge valve 100d is also provided by integral molding during the injection molding of the first case and the second case.

[0068] Incidentally, the compressor 11 is preferably stored in a compressor storage container 11a for isolating it from its surroundings. When the compressor 11 is operated, there is a possibility of discharging from the motor or inverter of the compressor 11 to the surroundings. By storing the compressor 11 in the compressor storage container 11a, even if the refrigerant leaks from the refrigerant circuit 10 and fills the internal space 100a of the storage container, the chance of encounter between the mixed gas of the refrigerant and the ignition source can be reduced, and the safety can be improved. The compressor storage container 11a is made of a conductive material. When the motor or inverter discharges, the charge can be quickly diffused to prevent local charging.

[0069] Also, when the refrigeration expansion device 14 is electronically controlled, it is preferably stored in an expansion device storage container 14a for isolating it from its surroundings. When the electronically controlled refrigeration expansion device 14 is operated, there is a possibility of discharging from the valve operating part to the surroundings. By storing the refrigeration expansion device 14 in the expansion device storage container 14a, even if the refrigerant leaks and fills the internal space 100a of the storage container, the chance of encounter between the mixed gas of the refrigerant and the ignition source can be reduced, and the safety can be improved. The expansion device storage container 14a is made of a conductive material. When the valve operating part discharges, the charge can be quickly diffused to prevent local charging.

[0070] It is preferable that both the storage of the compressor 11 in the compressor storage container 11a and the storage of the refrigeration expansion device 14 in the expansion device storage container 14a are carried out. The chance of encounter between the mixed gas of the refrigerant and the ignition source can be reduced, and the safety can be further improved.

[0071] <Modification Example 3> So far, the pressure in the internal space 100a of the storage container has been described as being 110 KPa (gauge pressure) or more when the Celsius temperature is 20 degrees. However, when propane is selected as the refrigerant in the refrigerant circuit 10, it is preferably 0.7 MPaG or more. The propane circulating inside the refrigerant circuit 10 is filled so as to be 0.70 to 0.75 MPaG when the Celsius temperature is 20 degrees. By setting the pressure of a predetermined gas surrounding the refrigerant circuit 10 to 0.7 MPaG, even if refrigerant leaks from the refrigerant circuit 10, the pressure difference with the surroundings of the refrigerant circuit 10 is sufficiently small, the leakage amount can be suppressed, and the safety can be improved.

[0072] <Example 2> Regarding the components common to the vehicle air conditioner of Example 1, the same reference numerals as in Example 1 are used and the description is omitted. Refer to FIG. 3. The vehicle air conditioner according to Example 2 includes a refrigerant circuit 110 in which a flammable refrigerant circulates inside, a heat radiation liquid circuit 80 in which a liquid heat medium circulates inside, a cooling liquid circuit 50 in which a liquid heat medium circulates inside, a heating liquid circuit 170 in which a liquid heat medium circulates inside, and a storage container 100 having an internal space 100a formed therein. The white arrows shown in the passenger compartment CR in FIG. 3 indicate the air flow when the air conditioning unit 60 is operated.

[0073] (Refrigerant Circuit) The refrigerant circuit 110 is configured such that a flammable refrigerant circulates inside. More specifically, the refrigerant circuit 110 is configured to connect the compressor 11, the heating water refrigerant heat exchanger 12, the heat radiating water refrigerant heat exchanger 13, the cooling expansion device 14, the cooling water refrigerant heat exchanger 15, and the compressor 11 again by piping, and the refrigerant circulates by flowing in this order. Although not shown, the refrigerant discharge port of the compressor 11 and the piping attached to the suction port of the compressor 11 use a well-known rubber hose to attenuate the amount of vibration transmitted from the compressor 11 to the connected components. In this embodiment, a refrigerant storage unit 16 for storing surplus refrigerant is disposed between the cooling water refrigerant heat exchanger 15 and the compressor 11. In this case, the refrigerant storage unit 16 functions as a so-called accumulator, separates the gaseous-phase refrigerant and the liquid-phase refrigerant, stores the liquid-phase refrigerant, and allows only the gaseous-phase refrigerant to flow out. Also, although not shown, the refrigerant storage unit 16 may be disposed between the heat radiating water refrigerant heat exchanger 13 and the cooling expansion device 14. In this case, the refrigerant storage unit 16 functions as a so-called liquid tank, separates the gaseous-phase refrigerant and the liquid-phase refrigerant, and allows a part of the liquid-phase refrigerant to flow out.

[0074] (Heating water refrigerant heat exchanger) The heating water refrigerant heat exchanger 12 exchanges heat without the high-temperature and high-pressure refrigerant flowing out of the compressor 11 coming into contact with the liquid heat medium sent from the heating pump 171, and transfers heat from the refrigerant circuit 110 to the heating liquid circuit 170. The refrigerant flowing out of the heating water refrigerant heat exchanger 12 becomes a low-temperature state and flows into the heat radiating water refrigerant heat exchanger 13.

[0075] (Heating liquid circuit) The vehicle air conditioner of this embodiment includes a heating liquid circuit 170. The heating liquid circuit 170 is configured such that a liquid heat medium circulates inside. More specifically, the heating liquid circuit 170 is configured to connect a heating pump 171, a heating water-refrigerant heat exchanger 12, a liquid heating device CH, an air heater 172, and the heating pump 171 again by piping, and the liquid heat medium circulates by flowing in this order. The heating liquid circuit 170 of this embodiment is thermally coupled to the refrigerant circuit 10. In FIG. 3, the arrow shown in the heating liquid circuit 170 indicates the flow direction of the heat medium when the heating liquid circuit 170 is operated.

[0076] The heating liquid circuit 170 can be said to be a circuit in which a liquid heat medium circulates inside and heats the air supplied to the passenger compartment CR by the air heater 172.

[0077] (Cooling operation) The operation during the cooling operation will be described. Similar to the cooling operation in Embodiment 1, the refrigerant circuit 110, the heat dissipation liquid circuit 80, the cooling liquid circuit 50, the blower 62, and the cooling fan 83 are operated. Also, the position of the mix door 63 and the opening degrees of the air outlets 64, 65, and 66 are adjusted in the same manner as in the cooling operation of Embodiment 1. On the other hand, the heating pump 171 and the liquid heating device CH are not operated.

[0078] As a result, the heat absorbed from the air by the air conditioner unit 60 is transferred to the air taken in from outside the vehicle V via the refrigerant circuit 110 and the heat dissipation heat exchanger 82. The air cooled by the air cooler 52 is supplied to the passenger compartment CR without being heated by the air heater 172.

[0079] (Heating operation) The operation during the heating operation will be described. Similar to the heating operation in the first embodiment, the heating liquid circuit 170 and the blower 62 are operated. More specifically, the heating pump 171, the liquid heating device CH, and the blower 62 are operated. Also, the position of the mix door 63 and the opening degrees of the air outlets 64, 65, and 66 are adjusted in the same manner as in the heating operation of the first embodiment. On the other hand, the compressor 11, the cooling fan 83, and the cooling pump 51 are not operated.

[0080] As a result, the heat generated by the liquid heating device CH is radiated to the air flowing there through the air heater 172 and supplied to the passenger compartment CR. The liquid heating device CH can be said to be a form of the heat source unit HS.

[0081] (Temperature conditioning operation) The operation during the temperature conditioning operation will be described. The compressor 11, the cooling pump 51, the heating pump 171, and the blower 62 are operated, and the valve opening degree of the cooling expansion device 14 is in a throttled state. The position of the mix door 63 is adjusted so that the respective amounts of air flowing into the air heater 172 and bypassing the air heater 172 do not become zero. The opening degrees of the air outlets 64, 65, and 66 are adjusted so as to distribute and blow out the conditioned air to the upper space and the lower space of the passenger compartment CR.

[0082] The heat radiation pump 81 and the cooling fan 83 are operated when the heat radiation from the refrigerant circuit 110 is under favorable conditions. The favorable conditions for the heat radiation from the refrigerant circuit 110 mean when the temperature of the passenger compartment CR is relatively high, the heat absorption amount by the air cooler 52 is sufficiently larger than the heat radiation amount by the air heater 172, and it is substantially a cooling operation.

[0083] The liquid heating device CH is operated when conditions require increasing the heat radiation amount from the air heater 172. The time when it is desired to increase the heat radiation amount from the air heater 172 means when the temperature of the passenger compartment CR is relatively low, the heat radiation amount by the air heater 172 is sufficiently larger than the heat absorption amount by the air cooler 52, and it is substantially a heating operation.

[0084] The heat absorbed from the air by the air cooler 52 in the air conditioner unit 60 is transferred to the air flowing through the air conditioner unit 60 via the cooling liquid circuit 50, the refrigerant circuit 110, the heating liquid circuit 170, and the air heater 172. Part of the air cooled by the air cooler 52 is heated by the air heater 172, and the remaining part bypasses the air heater 172. The air heated by the air heater 172 and the air that has bypassed the air heater 172 are mixed to achieve temperature harmonization, and then supplied to the passenger compartment CR via any of the air outlets 64, 65, 66.

[0085] <Other Embodiments> As long as the functions and effects of the present invention are achieved, the present invention is not limited to Embodiment 1, the modified example of Embodiment 1, and Embodiment 2. For example, various aspects shown in the modified example of Embodiment 1 can also be adopted as the modified example of Embodiment 2. Also, an electric heating type air heater (not shown) may be arranged upstream or downstream of the air heater 172 in the flow direction of the air flowing through the air supply space 61a. In addition, although the cooling liquid circuit 50, the heating liquid circuits 70, 170, and the heat radiation liquid circuit 80 have been described as independent liquid circuits, they may be set so that it is possible to select between an independent state and a continuous state. At this time, it is preferable that each liquid heat medium circulating through the cooling liquid circuit 50, the heating liquid circuits 70, 170, and the heat radiation liquid circuit 80 is composed of the same components.

Industrial Applicability

[0086] The vehicle air conditioner of the present invention is suitable for being mounted on a passenger vehicle.

Explanation of Reference Numerals

[0087] 10, 110... Refrigerant circuit 11... Compressor 11a... Compressor storage container 12... Heating water-refrigerant heat exchanger 13... Heat radiation water-refrigerant heat exchanger 14... Cooling expansion device 14a... Expansion device storage container 15... Cooling water-refrigerant heat exchanger 16…Refrigerant storage section 50…Liquid circuit for cooling 51…Cooling pump 52…Air cooler 60…Air conditioning unit 61…Air conditioning case 61a…Air supply space 62…Air supply device 63…Mixing door 64, 65, 66…Air outlets 70, 170…Liquid circuit for heating 71, 171…Heating pump 72, 172…Air heater 80…Liquid circuit for heat dissipation 81…Heat dissipation pump 82…Heat exchanger for heat dissipation 83…Cooling fan 100…Storage container 100a…Internal space of storage container 100au…Lower protruding space 100b…Pressure sensor 100c…Gas sensor 100d…Discharge valve 100in…Inner layer 100out…Outer layer 100z…Control unit V…Vehicle VD…Dash panel VW…Front compartment air intake CR…Passenger compartment FR…Front compartment CH…Liquid heating device HS…Heat source section Ge…Exhaust air M…Conductive material R…Resin material ER…Conductive resin material SR…Reinforcing resin material

Claims

1. An air conditioner for a vehicle mounted on a vehicle (V) having a passenger compartment (CR) and a front compartment (FR) located in front of the passenger compartment (CR), a refrigerant circuit (10, 110) disposed in the front compartment (FR) and through which a combustible refrigerant circulates inside, a cooling liquid circuit (50) through which a liquid heat medium circulates inside and absorbs heat from the air supplied to the passenger compartment (CR) by an air cooler (52), a heat dissipation liquid circuit (80) through which a liquid heat medium circulates inside and dissipates heat to the air taken into the front compartment (FR) by a heat dissipation heat exchanger (82), a storage container (100) having a storage container internal space (100a) formed therein, comprising, the refrigerant circuit (10, 110) and the cooling liquid circuit (50) are thermally coupled via a cooling water-refrigerant heat exchanger (15), the refrigerant circuit (10, 110) and the heat dissipation liquid circuit (80) are thermally coupled via a heat dissipation water-refrigerant heat exchanger (13), the refrigerant circuit (10, 110) is stored in the storage container internal space (100a), the storage container internal space (100a) is filled with a predetermined gas containing no combustible components and is sealed at a pressure higher than that of the front compartment (FR), an air conditioner for a vehicle.

2. The air conditioner for a vehicle according to claim 1, wherein the predetermined gas is air.

3. The air conditioner for a vehicle according to claim 1, wherein the predetermined gas is an inert gas.

4. The air conditioner for a vehicle according to claim 1, wherein the combustible refrigerant is propane, and the storage container internal space (100a) is sealed at a pressure of the predetermined gas at 20°C of 0.7 MPaG or more.

5. the storage container internal space (100a) has a downward protruding space (100au) protruding downward, The air conditioner for a vehicle according to claim 1, wherein the storage container (100) is provided with a discharge valve (100d) capable of discharging the predetermined gas from the downward protruding space (100au) to the outside of the storage container (100).

6. a heating liquid circuit (170) through which a liquid heat medium circulates inside and heats the air supplied to the passenger compartment (CR) by an air heater (172), comprising, The air conditioner for a vehicle according to any one of claims 1 to 5, wherein the refrigerant circuit (110) and the heating liquid circuit (170) are thermally coupled via a heating water-refrigerant heat exchanger (12).

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