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 formed while being surrounded by a conductive material (M).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 equipped with a vehicle air conditioner including a refrigerant circuit for conditioning the temperature of a passenger compartment where 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 where 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 which 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 impact, reduction of the use of chlorofluorocarbon refrigerants whose ozone layer depletion has been pointed out is required. Also, 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 impact and having little difference in pressure of the refrigerant circuit from chlorofluorocarbon refrigerants with a lot 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 arrange the refrigerant circuit inside a sealed container in advance. By doing so, even if the flammable refrigerant leaks, it can be prevented from diffusing into the surroundings or encountering an ignition source, 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 the sake of easy 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) in 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) in 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 formed surrounded by a conductive material (M), 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 figures, 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 a vehicle V, conditions outside air and inside air, and adjusts the temperature of a passenger compartment CR. The vehicle air conditioner includes a refrigerant circuit 10 in which a flammable refrigerant circulates, a heat radiation 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 radiation 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) The 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 the vehicle V into the front compartment FR is formed.

[0016] (Refrigerant circuit) The refrigerant circuit 10 is configured such that a flammable refrigerant circulates inside. More specifically, the refrigerant circuit 10 is configured to connect a compressor 11, a heat radiation 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 unit 16 for storing surplus refrigerant is arranged 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 vapor-phase refrigerant and the liquid-phase refrigerant, stores the liquid-phase refrigerant, and only the vapor-phase refrigerant flows out. Further, although not shown, the refrigerant storage unit 16 may be arranged between the heat radiation 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 vapor-phase refrigerant and the liquid-phase refrigerant, and a part of the liquid-phase refrigerant flows 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, or 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 preferred.

[0018] (Compressor) The compressor 11 sucks in and compresses the refrigerant in the refrigerant circuit 10 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 radiator water-refrigerant heat exchanger 13 in a high-temperature and high-pressure state.

[0019] (Radiator water-refrigerant heat exchanger) The radiator 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 circulating in the radiator liquid circuit 80 without contact, and transfers the heat of the refrigerant circuit 10 to the radiator liquid circuit 80. As a result, the refrigerant passing through it decreases in temperature while remaining at a high pressure, and the liquid heat medium in the radiator liquid circuit 80 increases in temperature. The radiator water-refrigerant heat exchanger 13 uses a heat exchanger with a well-known structure, and materials such as aluminum alloy or copper alloy are used for it. The refrigerant flowing out of the radiator water-refrigerant heat exchanger 13 flows into the cooling expansion device 14.

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

[0021] (Heat exchanger for heat release with water refrigerant) The heat exchanger 15 for heat release with water refrigerant exchanges heat without contacting the low-temperature and low-pressure refrigerant flowing out of the expansion device 14 for cooling and the liquid heat medium circulating in the liquid circuit 50 for cooling, and absorbs heat from the liquid circuit 50 for cooling. As a result, the refrigerant passing through it has its temperature rise while remaining at low pressure, and the liquid heat medium in the liquid circuit 50 for cooling has its temperature drop. As the heat exchanger 15 for heat release with water refrigerant, a heat exchanger with a well-known structure is used, and for its material, for example, an aluminum alloy or a copper alloy is used. The refrigerant flowing out of the heat exchanger 15 for heat release with water refrigerant is inhaled by the compressor 11 as vapor-phase refrigerant after passing through the refrigerant storage part 16.

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

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

[0024] (Heat release 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 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 is sometimes called a radiator. The air supplied to the heat dissipation heat exchanger 82 passes through the front chamber air intake VW provided in 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 the air conditioning unit 60 described later. When the cooled liquid heat medium passes through it, 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 is sometimes 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 conditioner 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, the occurrence of problems due to freezing and rust can be suppressed.

[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 section HS.

[0038] (Heat source section) The heat source section HS heats the liquid heat medium sent from the heating pump 71. The heat source section 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, an internal combustion engine for power to drive the vehicle V, an internal combustion engine for power having a function of generating electric power to drive the vehicle V, a vehicle traveling motor, an inverter for controlling this motor, etc. can be mentioned. The heat medium that has passed through the heat source section HS is heated and flows into the air heater 72.

[0039] (Air heater) The air heater 72 is also a component constituting the air conditioning unit 60, and when the heated liquid heat medium passes through it, it dissipates heat to the air passing through there. As a result, the temperature of the heat medium passing through there decreases, and the air passing through there is heated. The air heater 72 may be 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 throttle state, and the circulating refrigerant is adiabatically expanded. The heat radiation pump 81 is operated, and the liquid heat medium circulates inside the heat radiation 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 arranged 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 radiation 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 releases heat in the heat radiation water-refrigerant heat exchanger 13. The heat medium circulating in the heat radiation liquid circuit 80 absorbs heat in the heat radiation water-refrigerant heat exchanger 13, then flows into the heat radiation heat exchanger 82, and releases 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 radiation 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 heat dissipation 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 heat dissipation heat exchanger 82.

[0046] The heat absorbed from the air by the air conditioner unit 60 is transferred to the outside air by the heat dissipation 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 are 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 radiation 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 of 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 cooling 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 selected such that its material and structure satisfy requirements such as the air filled 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. The structure of the storage container 100 is preferably such that the cross-sectional shape is close to circular or elliptical, which can enhance the pressure resistance. The material constituting the storage container 100 is selected as the conductive material M. Details will be described later.

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

[0055] The combustion or explosive oxidation of the combustible refrigerant occurs when the mixed air (mixed gas) of the gas containing oxygen and the combustible refrigerant is at a mixed concentration between the upper limit value and the lower limit value 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 combustible refrigerant is to delay the time until the leakage continues and the mixed gas reaches the lower limit value 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 the combustible refrigerant leaks into the internal space 100a of the storage container, the combustible 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 the combined condition A. When the refrigerant leaks when the 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 the 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 the present 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 the discharged air Ge is discharged, 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 the 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] As the gas for filling the internal space 100a of the storage container, an inert gas with extremely low flammability may be selected. 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] Refer to FIG. 2A. For the material of the storage container 100, a conductive material M is selected. Thereby, the internal space 100a of the storage container is formed surrounded by the conductive material M. By adopting the conductive material M for the member forming the internal space 100a of the storage container, the local charging of electric charges on the inner surface of the inner layer 100in facing the internal space 100a of the storage container is suppressed, and the unintentional discharge into the internal space 100a of the storage container is prevented. And 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.

[0063] As the conductive material M, a highly rigid metal material such as iron or stainless steel is used. By using a highly rigid metal material for the conductive material M, the pressure resistance of the storage container 100 is increased, and even if the pressure of the predetermined gas filled in the internal space 100a of the storage container is sufficiently higher than that of the front chamber FR, it can be surely sealed.

[0064] Alternatively, by using the resin material R (conductive resin material ER) as the conductive material M, an increase in the weight of the storage container 100 can be suppressed. Examples of the conductive resin material ER include conductive polyacetal resins and those obtained by mixing metal fibers such as copper, nickel, and iron into a thermoplastic resin as disclosed in JP-A-2001-245418. Examples of the thermoplastic resin into which the metal fibers are mixed include single materials such as propylene, polyethylene, polystyrene, acrylonitrile-butadiene-styrene resin, polyethylene terephthalate resin, and polyamide resin, or blend materials.

[0065] When the conductive resin material ER is used as the material constituting the storage container 100, it is preferably a material that can be produced by injection molding. 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 by using a 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 internal space 100a of the storage container is performed via an enclosure valve (not shown). The enclosure valve is provided by integral molding during the injection molding of the first case and the second case.

[0066] And the discharge valve 100d is provided by integral molding during the injection molding.

[0067] Incidentally, the compressor 11 is preferably housed in a compressor storage container 11a for isolating it from its surroundings. When the compressor 11 is operated, there is a possibility of discharge from the motor or inverter of the compressor 11 to the surroundings. By housing 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.

[0068] Further, when the refrigeration expansion device 14 is electronically controlled, it is preferably housed in an expansion device storage container 14a for isolation from its surroundings. When operating the electronically controlled refrigeration expansion device 14, there is a possibility of discharging from the valve operating portion to the surroundings. By housing 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 portion discharges, the charge can be quickly diffused to prevent local charging.

[0069] It is preferable that both the compressor 11 be housed in the compressor storage container 11a and the refrigeration expansion device 14 be housed in the expansion device storage container 14a. 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.

[0070] <Modification Example 1> Referring to FIG. 2B, as the material constituting the storage container 100, a conductive resin material ER may be used for the inner layer 100in facing the internal space 100a of the storage container, and a reinforcing resin material SR may be used for the outer layer 100out provided on the outer surface of the inner layer 100in. By using the conductive resin material ER for the inner layer 100in, unintentional discharge into the internal space 100a of the storage container is prevented. By using the reinforcing resin material SR for the outer layer 100out, the strength of the storage container 100 is improved, the refrigerant circuit 10 can be reliably held, and it can be mounted on the vehicle V. Further, where the pressure of the gas enclosed in the internal space 100a of the storage container is higher than the pressure in the front chamber FR, expansion of the storage container 100 can be prevented, and the pressure in the internal space 100a of the storage container can be reliably maintained.

[0071] As the reinforcing resin material SR, 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 material of the continuous fiber composite base material include glass fiber, carbon fiber, and aramid fiber.

[0072] Also in this Modification 1, the storage container 100 is preferably formed by an injection molding process. 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 attaching 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 internal 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.

[0073] The discharge valve 100d of Modification 1 is also provided by integral molding during the injection molding of the first case and the second case.

[0074] <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. Referring 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.

[0075] (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 dissipation 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 arranged 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 only the gaseous-phase refrigerant flows out. Also, although not shown, the refrigerant storage unit 16 may be arranged between the heat dissipation 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 a part of the liquid-phase refrigerant flows out.

[0076] (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 in a low-temperature state and flows into the heat dissipation water refrigerant heat exchanger 13.

[0077] (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.

[0078] 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.

[0079] (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 in Embodiment 1. On the other hand, the heating pump 171 and the liquid heating device CH are not operated.

[0080] As a result, the heat absorbed from the air by the air conditioner unit 60 is transferred to the air taken in from the outside of 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.

[0081] (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.

[0082] 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.

[0083] (Temperature harmonization operation) The operation during the temperature harmonization 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 respectively and set to distribute and blow out the harmonized air to the upper space and the lower space of the passenger compartment CR.

[0084] The heat dissipation pump 81 and the cooling fan 83 are operated when the heat dissipation from the refrigerant circuit 110 is under favorable conditions. The favorable conditions for heat dissipation from the refrigerant circuit 110 refer to 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 in a cooling operation state.

[0085] The liquid heating device CH is operated when conditions are such that the heat radiation amount from the air heater 172 is desired to be increased. The time when the heat radiation amount from the air heater 172 is desired to be increased refers to 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 in a heating operation state.

[0086] 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. A 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.

[0087] <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 modification of Embodiment 1, and Embodiment 2. For example, the aspect shown in the modification of Embodiment 1 can also be adopted as the modification 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. Further, 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 the independent state and the continuous state can be selected. At this time, 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 preferably composed of the same components.

Industrial Applicability

[0088] The vehicle air conditioner of the present invention is suitable for mounting on a passenger vehicle.

Explanation of Reference Numerals

[0089] 10, 110... Refrigerant circuits 11... Compressor 11a... Compressor housing container 12... Heating water-refrigerant heat exchanger 13... Heat radiation water-refrigerant heat exchanger 14... Cooling expansion device 14a... Expansion device housing 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 the 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 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 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 formed surrounded by a conductive material (M), an air conditioner for a vehicle.

2. The air conditioner for a vehicle according to claim 1, wherein the conductive material (M) is a conductive resin material (ER).

3. The storage container (100) has an inner layer (100in) forming the storage container internal space (100a) and an outer layer (100out) provided outside the inner layer, the inner layer (100in) is formed of a conductive resin material (ER), the outer layer (100out) is formed of a reinforcing resin material (SR), the air conditioner for a vehicle according to claim 1.

4. The refrigerant circuit (10, 110) has a compressor (11), the compressor (11) is stored in a compressor storage container (11a), the air conditioner for a vehicle according to claim 1.

5. The refrigerant circuit (10, 110) has a cooling expansion device (14), the cooling expansion device (14) is stored in the storage container (11a), the air conditioner for a vehicle according to claim 1.

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 refrigerant circuit (110) and the heating liquid circuit (170) are thermally coupled via a heating water-refrigerant heat exchanger (12), the air conditioner for a vehicle according to any one of claims 1 to 5.

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