Air conditioning device for vehicle

Abstract

To provide an air conditioning device for a vehicle with improved safety and durability.SOLUTION: An air conditioning device for a vehicle comprises: a refrigerant circuit (10, 110) which is disposed in a front chamber (FR) of a vehicle (V), and in which a flammable refrigerant circulates; and a storage container (100) which stores the refrigerant circuit (10, 110) inside a storage container internal space (100a). The storage container internal space (100a) is filled with a predetermined gas from which moisture has been removed. The storage container internal space (100a) may also be provided with a moisture recovery agent (100wd).SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a vehicle air conditioning system equipped with a refrigerant circuit through which a flammable refrigerant circulates. [Background technology]

[0002] Many vehicles such as passenger cars are equipped with a vehicle air conditioner having a refrigerant circuit for adjusting the temperature of the passenger compartment. Patent Document 1 discloses a conventional technology related to a vehicle air conditioner.

[0003] The vehicle air conditioning system 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 is capable of adjusting the temperature of the passenger compartment, and is capable of adjusting the temperature of the passenger compartment. The refrigerant circuit (primary loop) has at least the function of cooling the heat medium circuit (secondary loop) to cool the passenger compartment.

[0004] The refrigerant used in the refrigerant circuit can be any known suitable single refrigerant or mixed refrigerant, and examples of such refrigerants include fluorocarbon refrigerants such as HFC (Hydro Fluoro Carbon) and HFO (Hydro Fluoro Olefin), hydrocarbon refrigerants (Hydro Carbon) such as propane and isobutane, and carbon dioxide.

[0005] From the perspective of reducing environmental impact, there is a need to reduce the use of fluorocarbon-based refrigerants, which have been pointed out as causing ozone layer depletion. Furthermore, refrigerant circuits that use carbon dioxide as a refrigerant face the challenge of high operating pressure. In this regard, hydrocarbon-based refrigerants have the advantage of being environmentally friendly and not significantly different in refrigerant circuit pressure from fluorocarbon-based refrigerants, which have a proven track record.

[0006] On the other hand, hydrocarbon refrigerants generally have a higher combustion rate than fluorocarbon refrigerants. Refrigerants with a high combustion rate are sometimes called flammable refrigerants. To prepare for the unintentional leakage of flammable refrigerants filled in the refrigerant circuit, a measure is taken to place the refrigerant circuit inside the containment vessel in advance. This prevents the flammable refrigerant from spreading to the surrounding area or coming into contact with an ignition source, thereby increasing safety even in the event of a leak. [Prior art documents] [Patent documents]

[0007] [Patent Document 1] Japanese Patent Publication No. 2022-079169 Summary of the Invention [Problem to be solved by the invention]

[0008] When the refrigerant circuit is operated to cool the passenger compartment, the temperature of the portion connected to the heat transfer medium circuit that cools the passenger compartment drops. The gas filling the internal space of the containment vessel is cooled in the portion of the refrigerant circuit where the temperature has dropped. If the gas surrounding the refrigerant circuit contains water vapor, it may condense and liquefy, and accumulate inside the containment vessel. The liquefied and accumulated moisture may be dispersed to electronic components that make up the refrigerant circuit due to vehicle vibration. Furthermore, if the containment vessel is made of metal, rust may occur. Alternatively, if the containment vessel is made of resin, this may lead to swelling of the resin or a decrease in its rigidity. In other words, the safety and durability of the vehicle air conditioning system may be reduced.

[0009] In addition to sealing the refrigerant circuit that uses a flammable refrigerant to cool the vehicle cabin with a containment vessel, further improvements in safety and durability are required. An object of the present invention is to provide a vehicle air conditioning system with improved safety and durability. [Means for solving the problem]

[0010] In the following description, reference numerals in the accompanying drawings are placed in parentheses to facilitate understanding of the present invention, but the present invention is not limited to the illustrated forms.

[0011] According to the present invention, there is provided a vehicle air conditioning system 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 chamber (FR) and through which a flammable refrigerant circulates; a cooling liquid circuit (50) through which a liquid heat medium circulates and which absorbs heat from air supplied to the passenger compartment (CR) by an air cooler (52); a heat-dissipating liquid circuit (80) in which a liquid heat medium circulates and dissipates heat to the air taken into the front chamber (FR) by a heat-dissipating heat exchanger (82); a storage container (100) having a storage container internal space (100a) formed therein; Equipped with 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 housed in the storage vessel internal space (100a), The internal space (100a) of the storage container is filled with a predetermined gas from which moisture has been removed, thereby providing an air conditioner for a vehicle. [Effects of the Invention]

[0012] The present invention can provide a vehicle air conditioner with improved safety and durability. [Brief explanation of the drawings]

[0013] [Figure 1] FIG. 1 is a schematic diagram of a vehicle air conditioner according to a first embodiment. [Figure 2] FIG. 2 is a schematic cross-sectional view taken along line 2-2 of FIG. [Figure 3]FIG. 3 is a schematic diagram of a vehicle air conditioner according to a second embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0014] The embodiment will be described with reference to the attached drawings, in which Fr indicates front, Rr indicates rear, Le indicates left, Ri indicates right, Up indicates top, and Dn indicates bottom.

[0015] Example 1 Referring to Figure 1, a vehicle air conditioner is mounted on a vehicle V and adjusts the temperature of the passenger compartment CR by adjusting the temperature of outside air and inside air drawn in by an air blower 62. The vehicle air conditioner includes a refrigerant circuit 10 through which a flammable refrigerant circulates, a heat dissipation liquid circuit 80 through which a liquid heat medium circulates, a cooling liquid circuit 50 through which the liquid heat medium circulates, and a containment vessel 100 formed with a containment vessel internal space 100a inside. In Figure 1, arrows shown in the refrigerant circuit 10, the heat dissipation liquid circuit 80, and the cooling liquid circuit 50 indicate the flow direction of the refrigerant or the heat medium when each circuit is operating.

[0016] (vehicle) A vehicle V has a passenger compartment CR where occupants sit, and a front compartment FR located in front of the passenger compartment CR and separated from the passenger compartment CR by a dash panel VD. A front compartment air intake VW is formed near the front end of the front compartment FR, allowing air from the front of the vehicle V to be introduced into the front compartment FR.

[0017] (refrigerant circuit) The refrigerant circuit 10 is configured to circulate a flammable refrigerant. More specifically, the refrigerant circuit 10 is configured to connect the compressor 11, the heat dissipation water-refrigerant heat exchanger 13, the air conditioning expansion device 14, the air conditioning water-refrigerant heat exchanger 15, and back to the compressor 11 via piping, and the refrigerant circulates by flowing in this order. Although not shown, well-known rubber hoses are used for the piping attached to the refrigerant discharge port and suction port of the compressor 11 to attenuate the transmission of vibration from the compressor 11 to the connected components. In this embodiment, a refrigerant reservoir 16 for storing excess refrigerant is located between the air conditioning water-refrigerant heat exchanger 15 and the compressor 11. In this case, the refrigerant reservoir 16 functions as a so-called accumulator, separating the gas phase refrigerant from the liquid phase refrigerant, storing the liquid phase refrigerant, and discharging only the gas phase refrigerant. Although not shown, the refrigerant reservoir 16 may be disposed between the heat dissipation water-refrigerant heat exchanger 13 and the air conditioning expansion device 14. In this case, the refrigerant reservoir 16 functions as a so-called liquid tank, separates the gas phase refrigerant from the liquid phase refrigerant, and allows a portion of the liquid phase refrigerant to flow out.

[0018] (refrigerant) In this embodiment, a refrigerant is selected that has a relatively low ozone depletion potential and a relatively low pressure during operation of the refrigerant circuit 10. Specifically, hydrocarbons such as propane, propylene, and isobutane, as well as ammonia, are used. These refrigerants have a significantly lower ozone depletion potential than the fluorocarbon refrigerant R134a, and can be operated at significantly lower pressures than when carbon dioxide is used as the refrigerant. On the other hand, when mixed with oxygen or a gas containing oxygen, they exhibit high flammability depending on the concentration range of the mixture. Propane and isobutane are less irritating than ammonia and are therefore preferred.

[0019] (Compressor) The compressor 11 draws in, compresses, and discharges refrigerant from the refrigerant circuit 10. In this embodiment, the compressor 11 is an electric compressor. The compressor 11 has a compression mechanism, a motor that drives the compression mechanism, and an inverter that controls the 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 dissipation water-refrigerant heat exchanger 13 in a high-temperature, high-pressure state.

[0020] (Water refrigerant heat exchanger for heat radiation) The heat dissipation water-refrigerant heat exchanger 13 exchanges heat between the high-temperature, high-pressure refrigerant discharged from the compressor 11 and the liquid heat medium circulating in the heat dissipation liquid circuit 80 without contact, transferring heat from the refrigerant circuit 10 to the heat dissipation liquid circuit 80. As a result, the temperature of the refrigerant passing therethrough decreases while remaining at high pressure, while the temperature of the liquid heat medium in the heat dissipation liquid circuit 80 increases. The heat dissipation water-refrigerant heat exchanger 13 is a heat exchanger of known structure, and is made of, for example, an aluminum alloy or a copper alloy. The refrigerant flowing out of the heat dissipation water-refrigerant heat exchanger 13 becomes medium-temperature and high-pressure and flows into the air-conditioning expansion device 14. 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.

[0021] (Air conditioning expansion device) The cooling expansion device 14 adiabatically expands the medium-temperature, high-pressure refrigerant that has flowed out of the heat dissipation water-refrigerant heat exchanger 13, changing its state to low temperature and low pressure. An expansion device of well-known structure is used for the cooling expansion device 14. The refrigerant that has flowed 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.

[0022] (Water-refrigerant heat exchanger for cooling) The cooling water-refrigerant heat exchanger 15 exchanges heat between the low-temperature, low-pressure refrigerant flowing out of the cooling expansion device 14 and the liquid heat transfer medium circulating in the cooling liquid circuit 50 without contacting each other, thereby absorbing heat from the cooling liquid circuit 50. As a result, the temperature of the refrigerant passing therethrough increases while remaining at low pressure, while the temperature of the liquid heat transfer medium in the cooling liquid circuit 50 decreases. The cooling water-refrigerant heat exchanger 15 is a heat exchanger of known structure, and is made of, for example, an aluminum alloy or a copper alloy. The refrigerant flowing out of the cooling water-refrigerant heat exchanger 15 passes through a refrigerant reservoir 16, and the gas phase refrigerant is drawn into the compressor 11. The heat transfer medium flowing out of the cooling water-refrigerant heat exchanger 15 becomes cold and flows into the air cooler 52.

[0023] (refrigerant reservoir) In this embodiment, the refrigerant storage unit 16 functions as an accumulator. The refrigerant flowing out of the cooling water-refrigerant heat exchanger 15 is separated into gas-phase refrigerant and liquid-phase refrigerant, the gas-phase refrigerant flows toward the compressor 11, and the excess refrigerant is stored as liquid-phase refrigerant. Although not shown, the refrigerant storage unit 16 includes a tank portion having an internal space, a refrigerant inlet pipe through which the refrigerant flowing out of the cooling water-refrigerant heat exchanger 15 flows into the internal space of the tank portion, a refrigerant outlet pipe through which the gas-phase refrigerant separated in the internal space of the tank portion flows out, and a refrigerant moisture recovery agent disposed in the internal space of the tank portion.

[0024] (Liquid circuit for heat radiation) The heat dissipation liquid circuit 80 is configured so that a liquid heat medium circulates inside it. More specifically, the heat dissipation liquid circuit 80 is configured so that piping connects a heat dissipation pump 81, a heat dissipation water-refrigerant heat exchanger 13, a heat dissipation heat exchanger 82, and again the heat dissipation pump 81, and the liquid heat medium circulates by flowing in this order.

[0025] (Heat medium for heat dissipation liquid circuit) The liquid heat transfer medium circulating through the heat dissipation liquid circuit 80 is, for example, a mixture of water with a glycol-based solvent and a rust inhibitor added, which can prevent problems caused by freezing or rust of the heat transfer medium inside the heat dissipation liquid circuit 80.

[0026] (heat dissipation pump) The heat dissipation pump 81 is a pump having a known structure that pumps the liquid heat medium in the heat dissipation liquid circuit 80. The heat medium sent from the heat dissipation pump 81 flows into the heat dissipation water-refrigerant heat exchanger 13 where it exchanges heat, and is then sent to the heat dissipation heat exchanger 82.

[0027] (heat exchanger and cooling fan) The heat-dissipating heat exchanger 82 exchanges heat between the high-temperature liquid heat medium flowing out of the heat-dissipating water-refrigerant heat exchanger 13 and the air flowing therethrough without contact, thereby dissipating heat from the heat medium in the heat-dissipating liquid circuit 80. The heat-dissipating heat exchanger 82 is sometimes called a radiator. The air supplied to the heat-dissipating heat exchanger 82 passes through a front-chamber air intake VW provided at the front of the vehicle V (at the front of the front chamber FR) and reaches the heat-dissipating heat exchanger 82. A cooling fan 83 is provided along the air flow direction to adjust the heat dissipation capacity of the heat-dissipating heat exchanger 82, and is operated or stopped depending on the temperature conditions. The heat medium flowing out of the heat-dissipating heat exchanger 82 has its temperature lowered and is sucked into the heat-dissipating pump 81. In FIG. 1, four open arrows lined up near the cooling fan 83 indicate the air flow when the cooling fan 83 is operating.

[0028] 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.

[0029] (liquid circuit for cooling) The cooling liquid circuit 50 is configured so that a liquid heat transfer medium circulates inside. More specifically, the cooling liquid circuit 50 is configured so that piping connects a cooling pump 51, a cooling water-refrigerant heat exchanger 15, an air cooler 52, and the cooling pump 51 again, and the liquid heat transfer medium circulates by flowing in this order.

[0030] (Heat medium for cooling liquid circuit) The liquid heat transfer medium circulating through the cooling liquid circuit 50 is, for example, a mixture of water with a glycol-based solvent and a rust inhibitor added thereto, which can prevent problems caused by freezing or rust of the heat transfer medium inside the cooling liquid circuit 50.

[0031] (cooling pump) The cooling pump 51 is a pump having a known structure that pumps the liquid heat medium in the cooling liquid circuit 50. The heat medium sent from the cooling pump 51 flows into the cooling water-refrigerant heat exchanger 15 for heat exchange, and is then sent to the air cooler 52.

[0032] (Air cooler) The air cooler 52 is also a component of the air conditioning unit 60, which will be described later, and absorbs heat from the air passing through it as the cooled liquid heat transfer medium passes through it. As a result, the temperature of the heat transfer medium passing through it rises, and the air passing through it is cooled. The air cooler 52 is sometimes called a water cooler or water core. A heat exchanger with a well-known structure is used for the air cooler 52, and examples of its material include aluminum alloys and copper alloys. The heat transfer medium that flows out of the air cooler 52 is sucked into the air conditioning pump 51.

[0033] The cooling liquid circuit 50 can be said to be a circuit in which a liquid heat medium circulates 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 draws in air from the vehicle compartment CR or outside air from the vehicle V, conditions the temperature, and then supplies the air to the vehicle compartment CR. In this embodiment, the air conditioning unit 60 is located adjacent to the dash panel VD, i.e., at the front end of the vehicle compartment CR. The air conditioning unit 60 includes an air conditioning case 61 having an air flow space 61a formed therein, a blower 62 that blows air into the air flow space 61a, an air cooler 52 that is located in the air flow space 61a and is capable of cooling the blown air, an air heater 72 that is capable of heating the air that flows out of the air cooler 52, and a mix door 63 that adjusts the ratio of air flowing into the air heater 72 to air that bypasses the air. The temperature-conditioned air becomes conditioned air and is supplied to the vehicle compartment CR through multiple air outlets 64, 65, and 66 provided in the air conditioning case 61. In FIG. 1, the open arrows in the vehicle compartment CR indicate the air flow when the air conditioning unit 60 is operating.

[0035] (Heating liquid circuit) In this embodiment, the vehicle air conditioning system may include a heating liquid circuit 70. The heating liquid circuit 70 is configured so that a liquid heat transfer medium circulates therethrough. More specifically, the heating liquid circuit 70 is configured so that a heating pump 71, a heat source HS, an air heater 72, and again the heating pump 71 are connected by piping, and the liquid heat transfer medium circulates by flowing in this order. In this embodiment, the heating liquid circuit 70 is not connected to the refrigerant circuit 10. The arrows shown in the heating liquid circuit 70 in FIG. 1 indicate the flow direction of the heat transfer medium when the heating liquid circuit 70 is operating.

[0036] (heat medium for heating liquid circuit) The liquid heat transfer medium circulating through the heating liquid circuit 70 is, for example, a mixture of water with a glycol-based solvent and a rust inhibitor added, which can prevent problems caused by freezing or rust of the heat transfer medium inside the heating liquid circuit 70.

[0037] (heating pump) The heating pump 71 is a pump having a known structure that pumps the liquid heat medium in the heating liquid circuit 70. The heat medium sent from the heating pump 71 flows into the heat source section HS.

[0038] (Heat source) The heat source HS heats the liquid heat medium sent from the heating pump 71. The heat source and structure of the heat source HS are not particularly limited as long as it can supply the amount of heat required by the air conditioning unit 60, but examples include an electrically heated hot water generator, a power internal combustion engine for driving the vehicle V, an electric power internal combustion engine that has the function of generating electricity to drive the vehicle V, a vehicle drive motor, and an inverter that controls this motor. The heat medium that passes through the heat source HS is heated and flows into the air heater 72.

[0039] (Air heater) The air heater 72 is also a component of the air conditioning unit 60, and as the heated liquid heat transfer medium passes through it, it dissipates heat to the air passing through. As a result, the temperature of the heat transfer medium passing through it drops, and the air passing through it is heated. The air heater 72 is sometimes called a hot water heater or hot water core. A heat exchanger of known structure is used for the air heater 72, and examples of materials used for the air heater 72 include aluminum alloys and copper alloys. The heat transfer medium that flows out of the air heater 72 is drawn into the heating pump 71.

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

[0041] (Cooling operation) The operation during cooling operation will be described. The compressor 11 is operated, and the refrigerant circulates inside the refrigerant circuit 10. The valve opening of the cooling expansion device 14 is reduced, 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 arranged in the air blowing space 61a. The position of the mix door 63 is adjusted to maximize the proportion of air bypassing the air heater 72. The openings of the air outlets 64, 65, and 66 are each adjusted to blow conditioned air into the space above the passenger compartment CR. The cooling fan 83 is also operated, and outside air from the vehicle V taken in through the front compartment air intake VW is supplied to the heat dissipation heat exchanger 82.

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

[0043] (Heating operation) The operation during heating operation will be described. The heating pump 71 operates, and the liquid heat medium circulates inside the heating liquid circuit 70. The blower 62 operates, and air is supplied to the air blowing space 61a. The position of the mix door 63 is adjusted to maximize the ratio of air flowing into the air heater 72. The openings of the air outlets 64, 65, and 66 are each adjusted to blow conditioned air into the space below the passenger compartment CR. Furthermore, if the heat source HS is an internal combustion engine for power, it operates and generates heat. If the heat source HS is an electrically heated hot water generator, the electrically heated hot water generator operates and generates heat.

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

[0045] (Temperature adjustment operation) The operation during temperature conditioning operation will be described. The compressor 11, heat dissipation pump 81, air conditioning pump 51, and blower 62 are operated, and the valve opening of the air conditioning expansion device 14 is throttled. The position of the mix door 63 is adjusted so that the amount of air flowing into the air heater 72 and the amount of air bypassing the air heater 72 do not become zero. The openings of the air outlets 64, 65, and 66 are each adjusted so that the conditioned air is distributed and blown out to the upper and lower spaces of the passenger compartment CR. In addition, the cooling fan 83 is operated, and outside air from the vehicle V taken in through the front compartment air intake VW is supplied to the heat dissipation heat exchanger 82.

[0046] The heat absorbed from the air by the air conditioning unit 60 passes through the refrigerant circuit 10 and is transferred to the outside air by the heat dissipation heat exchanger 82. A portion of the air cooled by the air cooler 52 is heated by the air heater 72, and the remaining portion bypasses the air heater 72. The air heated by the air heater 72 and the air that bypassed the air heater 72 are mixed together to be temperature-adjusted, and then supplied to the passenger compartment CR via one of the air outlets 64, 65, and 66.

[0047] (containment vessel) Referring to FIG. 1, the vehicle air conditioning system has a containment vessel 100 having a containment vessel internal space 100a formed therein. The containment vessel internal space 100a houses a refrigerant circuit 10. It can also be said that the refrigerant circuit 10 is housed in the containment vessel internal space 100a. More strictly speaking, the containment vessel internal space 100a houses not only the refrigerant circuit 10 but also a part of the heat dissipation liquid circuit 80 and a part of the cooling liquid circuit 50. The containment vessel internal space 100a is connected to the outside of the containment vessel 100 via a pipe for sending a heat medium to the heat dissipation water-refrigerant heat exchanger 13, a pipe for sending the heat medium flowing out of the heat dissipation water-refrigerant heat exchanger 13 to the heat dissipation heat exchanger 82, a pipe for sending the heat medium to the cooling water-refrigerant heat exchanger 15, and a pipe for sending the heat medium flowing out of the cooling water-refrigerant heat exchanger 15 to the air cooler 52.

[0048] (Exhaust valve) Refer to FIG. 2. This shows a schematic cross section of the containment vessel 100 taken along line 2-2 in FIG. 1. A downwardly protruding space 100au is formed on the bottom surface of the containment vessel internal space 100a, and a discharge valve 100d is provided at the bottom thereof. The discharge valve 100d is electrically connected to a control unit 100z installed outside the containment vessel 100. The valve opening degree is controlled in response to a signal from the control unit 100z. The discharge valve 100d is normally closed, but opens when a pressure sensor 100b or a gas sensor 100c (described later) detects a leak of refrigerant circulating through the refrigerant circuit 10, and discharges the leaked refrigerant together with the charged gas to the outside of the containment vessel 100 as discharge gas Ge.

[0049] (Pressure sensors, gas sensors) Additionally, a pressure sensor 100b and a gas sensor 100c are disposed in the containment vessel internal space 100a and are electrically connected to a control unit 100z installed outside the containment vessel 100. The pressure sensor 100b and the gas sensor 100c transmit the detected physical quantities to the control unit 100z.

[0050] (Control unit) A control unit 100z is disposed outside the containment vessel 100. The control unit 100z may be provided independently. Alternatively, although not shown, the control unit 100z may be provided integrally with another control unit that controls other vehicle components. The control unit 100z is electrically connected to the pressure sensor 100b, the gas sensor 100c, the exhaust valve 100d, as well as 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 (see FIG. 1), to control the vehicle air conditioner. Alternatively, if a flammable refrigerant leaks from the refrigerant circuit 10, the control unit 100z detects this and controls the opening of the exhaust valve 100d to exhaust the leaked refrigerant to the outside of the containment vessel 100. This improves the safety of the vehicle air conditioner.

[0051] (specified gas) The containment vessel internal space 100a is filled with a predetermined gas that does not contain any flammable components. The predetermined gas is composed of components that maintain a gaseous state within the operating temperature range of the refrigerant circuit 10, and is appropriately selected from air (a mixture mainly composed of nitrogen and oxygen), nitrogen, carbon dioxide, and inert gases such as argon and helium. Furthermore, the predetermined gas is a gas from which moisture has been removed.

[0052] When the refrigerant circuit 10 is operated to condition the temperature of the passenger compartment CR, the refrigerant circulates inside the refrigerant circuit 10 and is adiabatically expanded in the air-conditioning expansion device 14. As a result, the refrigerant circuit 10 is at low temperature and low pressure from the downstream side of the air-conditioning expansion device 14 to the suction side of the compressor 11. Here, moisture has been removed from the predetermined gas filled into the containment vessel internal space 100a, so even if the gas comes into contact with the low-temperature, low-pressure section of the refrigerant circuit 10, condensation water will not occur. Alternatively, even if condensation water occurs, it will be in a sufficiently small amount.

[0053] The target temperature of the refrigerant adiabatically expanded by the cooling expansion device 14 is set to about 2°C during cooling, and to about 2°C or higher during temperature adjustment, and the valve opening of the cooling expansion device 14 is adjusted accordingly. If the temperature of the refrigerant circuit 10 falls below 0°C, condensed water generated on the surface of the air cooler 52 may freeze, blocking the air flow path of the air cooler 52 and impairing its ability to cool the air.

[0054] The predetermined gas filled into the containment vessel internal space 100a is a gas from which moisture has been removed, and more specifically, it is preferable that moisture has been removed to the extent that condensation does not occur at 2°C, and the amount of water vapor contained is preferably 5.5 g / m3 or less in the state of pressure filled into the containment vessel internal space 100a. Condensation does not occur at the temperature during operation of the refrigerant circuit 10, and this can improve the safety and durability of the vehicle air conditioner.

[0055] Furthermore, it is preferable that the predetermined gas filled into the containment vessel internal space 100a has been removed to such an extent that condensation does not occur at 0°C. Specifically, the amount of water vapor contained therein is preferably 4.8 g / m3 or less at the pressure filled into the containment vessel internal space 100a. When the temperature of the containment vessel internal space 100a is relatively high and the temperature outside the containment vessel 100 is relatively low, the containment vessel 100 is cooled, the temperature of the inner wall surface of the containment vessel internal space 100a drops, and condensation may occur. Here, by setting the amount of water vapor contained in the gas filled into the containment vessel internal space 100a to 4.8 g / m3, which is the saturated water vapor amount at 0°C, or less, condensation does not occur under conditions where the temperature outside the containment vessel 100 is higher than 0°C. Furthermore, when the temperature outside the containment vessel 100 is 0°C or lower, condensation may occur on the inner wall surface of the containment vessel internal space 100a, but because the temperature of the inner wall surface drops below 0°C, the condensation freezes and solidifies, adhering to the inner wall surface. As a result, liquid water is prevented from scattering inside the containment vessel internal space 100a, and when the containment vessel 100 is made of resin, swelling of the resin and a decrease in rigidity are less likely to occur, improving the safety and durability of the vehicle air conditioning system.

[0056] (Moisture recovery agent) See FIG. 1. A moisture recovery agent 100wd is placed in the containment vessel internal space 100a to absorb gaseous moisture. This moisture recovery agent 100wd is made of, for example, silica gel or zeolite, which does not contain moisture. Silica gel and zeolite have a large surface area and can adsorb water molecules floating in the gas and recover water molecules from the surrounding gas. The moisture recovery agent 100wd is prepared by storing granular material in a storage bag, and is fixed inside the containment vessel internal space 100a to prevent it from scattering or dispersing due to vibrations of the vehicle V, etc.

[0057] The moisture recovery agent 100wd disposed in the containment vessel internal space 100a is preferably located closer to the low-pressure flow path from the cooling expansion device 14 to the compressor 11 than to the high-pressure flow path from the compressor 11 to the cooling expansion device 14. The temperature of the low-pressure flow path drops when the refrigerant circuit 10 is in operation, making condensation more likely to occur. Therefore, disposing the moisture recovery agent 100wd in a region adjacent to the low-pressure flow path effectively suppresses the formation of condensation. Furthermore, as shown in FIG. 1, the moisture recovery agent 100wd is preferably disposed in a region adjacent to the section between the cooling expansion device 14 and the cooling water-refrigerant heat exchanger 15. When the refrigerant circuit 10 is in operation, the temperature of the section from the cooling expansion device 14 to the cooling water-refrigerant heat exchanger 15 is lower than that of the low-pressure flow path. Disposing the moisture recovery agent 100wd in a region adjacent to this section more effectively suppresses the formation of condensation.

[0058] (Filling pressure) Here, the containment vessel internal space 100a is preferably filled with a predetermined gas so that the pressure at room temperature is higher than atmospheric pressure. For example, when the temperature is 20 degrees Celsius, the containment vessel internal space 100a is filled with a predetermined gas and sealed so that the pressure is 110 KPa (gauge pressure) or higher.

[0059] (Material) The containment vessel 100 is not particularly limited in terms of material or structure, as long as it satisfies the following requirements: the pressure does not drop significantly due to the permeation of the gas filled therein even after the vehicle V has been in use; it has the strength to hold the compressor 11 and various heat exchangers; and it has temperature resistance within the operating temperature range of the vehicle V. Examples of materials for the containment vessel 100 include metal materials M such as iron and stainless steel, and resin materials R such as fiber-reinforced nylon. The structure is preferably as close to a circular or elliptical cross-sectional shape as possible, as this can increase pressure resistance.

[0060] The refrigerant circuit 10 is housed in a storage vessel internal space 100a, which is preferably filled with a predetermined gas that does not contain flammable components and sealed to maintain a higher pressure than the front chamber FR. Even if water vapor attempts to infiltrate into the storage vessel internal space 100a from around the storage vessel 100, the pressure in the storage vessel internal space 100a is higher than that around the storage vessel 100, so the intrusion of water vapor is prevented.

[0061] In this embodiment, the containment vessel internal space 100a has a downwardly protruding space 100au that protrudes downward, and the containment vessel 100 is provided with a discharge valve 100d that can discharge a predetermined gas from the downwardly protruding space 100au to the outside of the containment vessel 100. Therefore, if a flammable refrigerant leaks into the containment vessel internal space 100a, the flammable refrigerant can be systematically discharged to the outside of the containment vessel 100 via the discharge valve 100d, thereby improving safety.

[0062] The effects of this embodiment are summarized below.

[0063] When the refrigerant circuit 10 is operated to temperature-condition the passenger compartment CR, the compressor 11 is driven, and the refrigerant circulates within the refrigerant circuit 10. During cooling or temperature-conditioning operation, the circulating refrigerant is adiabatically expanded in the cooling expansion device 14, flows into the cooling water-refrigerant heat exchanger 15, and cools the heat medium flowing through the cooling liquid circuit 50. That is, the refrigerant circuit 10 is kept at a low temperature from the downstream side of the cooling expansion device 14 to the suction side of the compressor 11. If the gas filling the periphery of the refrigerant circuit 10 contains water vapor, the water vapor may condense and form condensation on the outer surface of the refrigerant circuit 10 from the cooling expansion device 14 to the compressor 11, generating liquid water. In this embodiment, the predetermined gas filling the containment vessel internal space 100a is dehydrated, preventing condensation.

[0064] Furthermore, in this embodiment, a moisture recovery agent 100wd is placed in the containment vessel internal space 100a. The containment vessel internal space 100a is filled with a predetermined gas from which moisture has been removed during production of the vehicle V or the vehicle air conditioning system. However, over time, water vapor may enter the containment vessel internal space 100a by permeating the containment vessel 100 or through the interface between the containment vessel 100 and the surface of the piping connecting the outside and inside of the containment vessel 100. In this embodiment, the moisture recovery agent 100wd absorbs water vapor, thereby maintaining the containment vessel internal space 100a in a dry state, thereby preventing condensation in the refrigerant circuit 10 for a long period of time.

[0065] Furthermore, in this embodiment, the moisture recovery agent 100wd is disposed in an area closer to the low-pressure flow path from the cooling expansion device 14 to the compressor 11 than to the high-pressure flow path from the compressor 11 to the cooling expansion device 14. When the refrigerant circuit 10 is in cooling operation or temperature adjustment operation, the surface temperature of the low-pressure flow path from the cooling expansion device 14 to the compressor 11 decreases, and the relative humidity of the gas surrounding the low-pressure flow path increases. In this embodiment, the moisture recovery agent 100wd is disposed in an area closer to the low-pressure flow path, which suppresses the increase in relative humidity and effectively prevents condensation in the refrigerant circuit 10.

[0066] Furthermore, in this embodiment, the specified gas filled into the containment vessel internal space 100a is filled so that its pressure at room temperature is higher than atmospheric pressure, thereby preventing water vapor from entering the containment vessel 100 from the outside to the inside.

[0067] According to this embodiment, it is possible to provide a vehicle air conditioner with improved safety and durability.

[0068] <Example 2> Components common to the vehicle air conditioner of the first embodiment are assigned the same reference numerals as in the first embodiment, and descriptions thereof will be omitted. See Fig. 3. The vehicle air conditioner of the second embodiment includes a refrigerant circuit 110 through which a flammable refrigerant circulates, a heat dissipation liquid circuit 80 through which a liquid heat medium circulates, a cooling liquid circuit 50 through which a liquid heat medium circulates, a heating liquid circuit 170 through which a liquid heat medium circulates, and a containment vessel 100 having a containment vessel internal space 100a formed therein. In Fig. 3, the open arrows indicated in the passenger compartment CR indicate the air flow when the air conditioning unit 60 is operating.

[0069] (refrigerant circuit) The refrigerant circuit 110 is configured to circulate a flammable refrigerant. 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 air-conditioning expansion device 14, the air-conditioning water-refrigerant heat exchanger 15, and back to the compressor 11 via piping. The refrigerant circulates by flowing in this order. Although not shown, well-known rubber hoses are used for the piping attached to the refrigerant discharge port and suction port of the compressor 11 to attenuate the transmission of vibration from the compressor 11 to the connected components. In this embodiment, a refrigerant reservoir 16 for storing excess refrigerant is located between the air-conditioning water-refrigerant heat exchanger 15 and the compressor 11. In this case, the refrigerant reservoir 16 functions as a so-called accumulator, separating the gas phase refrigerant from the liquid phase refrigerant, storing the liquid phase refrigerant, and discharging only the gas phase refrigerant. Although not shown, the refrigerant reservoir 16 may be disposed between the heat dissipation water-refrigerant heat exchanger 13 and the air conditioning expansion device 14. In this case, the refrigerant reservoir 16 functions as a so-called liquid tank, separates the gas phase refrigerant from the liquid phase refrigerant, and allows a portion of the liquid phase refrigerant to flow out.

[0070] (Water-refrigerant heat exchanger for heating) The heating water-refrigerant heat exchanger 12 exchanges heat between the high-temperature, high-pressure refrigerant flowing out of the compressor 11 and the liquid heat medium sent from the heating pump 171 without contacting each other, 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 is in a low-temperature state and flows into the heat-dissipating water-refrigerant heat exchanger 13.

[0071] (Heating liquid circuit) The vehicle air conditioning system of this embodiment includes a heating liquid circuit 170. The heating liquid circuit 170 is configured so that a liquid heat medium circulates therein. More specifically, the heating liquid circuit 170 is configured so that piping connects 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, 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 arrows shown in the heating liquid circuit 170 indicate the flow direction of the heat medium when the heating liquid circuit 170 is operating.

[0072] The heating liquid circuit 170 can be said to be a circuit through which a liquid heat medium circulates and which heats the air supplied to the passenger compartment CR by the air heater 172.

[0073] (Cooling operation) The operation during cooling operation will now be described. As in the cooling operation in the first embodiment, 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. The position of the mix door 63 and the openings of the air outlets 64, 65, and 66 are also adjusted as in the cooling operation in the first embodiment. On the other hand, the heating pump 171 and the liquid heating device CH are not operated.

[0074] As a result, the heat absorbed from the air flowing through the air blowing space 61a of the air conditioning 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.

[0075] (Heating operation) The operation during heating operation will be described. As in the heating operation in the first embodiment, the heating liquid circuit 170 and the blower 62 operate. More specifically, the heating pump 171, the liquid heating device CH, and the blower 62 operate. The position of the mix door 63 and the openings of the air outlets 64, 65, and 66 are also adjusted as in the heating operation in the first embodiment. On the other hand, the compressor 11, the cooling fan 83, and the cooling pump 51 do not operate.

[0076] As a result, the heat generated in the liquid heating device CH is dissipated in the air heater 172 to the air flowing therethrough, and is supplied to the vehicle compartment CR. The liquid heating device CH can be said to be one form of the heat source section HS.

[0077] (Temperature adjustment operation) The operation during temperature conditioning operation will be described. The compressor 11, cooling pump 51, heating pump 171, and blower 62 are operated, and the valve opening of the cooling expansion device 14 is narrowed. The position of the mix door 63 is adjusted so that the amount of air flowing into the air heater 172 and the amount of air bypassing the air heater 172 do not become zero. The openings of the air outlets 64, 65, and 66 are each adjusted so that the conditioned air is distributed and blown out to the upper and lower spaces of the passenger compartment CR.

[0078] The heat dissipation pump 81 and the cooling fan 83 operate when conditions are favorable for heat dissipation from the refrigerant circuit 110. Conditions favorable for heat dissipation from the refrigerant circuit 110 include when the temperature of the passenger compartment CR is relatively high, the amount of heat absorbed by the air cooler 52 is sufficiently greater than the amount of heat dissipated by the air heater 172, and the cooling operation is essentially performed.

[0079] The liquid heating device CH operates under conditions where it is desired to increase the amount of heat released from the air heater 172. When it is desired to increase the amount of heat released from the air heater 172, the temperature of the passenger compartment CR is relatively low, the amount of heat released by the air heater 172 is sufficiently greater than the amount of heat absorbed by the air cooler 52, and the vehicle is essentially operating in a heating mode.

[0080] Heat absorbed from the air by air cooler 52 in air conditioning unit 60 is transferred to air flowing through air blowing space 61a of air conditioning unit 60 via cooling liquid circuit 50, refrigerant circuit 110, heating liquid circuit 170, and air heater 172. A portion of the air cooled by air cooler 52 is heated by air heater 172, and the remaining portion bypasses air heater 172. The air heated by air heater 172 and the air that bypasses air heater 172 are mixed together to be temperature-adjusted, and the air is supplied to the vehicle interior CR via any one of air outlets 64, 65, and 66.

[0081] The vehicle air conditioner of the second embodiment has a moisture recovery agent 100wd disposed in the containment vessel internal space 100a, similar to the vehicle air conditioner of the first embodiment. The vehicle air conditioner of the second embodiment has the same effects as the first embodiment.

[0082] <Other Examples> As long as the functions and effects of the present invention are achieved, the present invention is not limited to the first and second embodiments. For example, an electric air heater (not shown) may be disposed upstream or downstream of the air heater 172 in the direction of air flow through the air blowing space 61a. Although the cooling liquid circuit 50, the heating liquid circuits 70 and 170, and the heat dissipation liquid circuit 80 have been described as independent liquid circuits, they may be configured so that they can be selectively connected or independent. In this case, it is preferable that the liquid heat transfer media circulating through the cooling liquid circuit 50, the heating liquid circuits 70 and 170, and the heat dissipation liquid circuit 80 each have the same components. In this case, the same effects as those of the vehicle air conditioner of the first embodiment are achieved. [Industrial Applicability]

[0083] The vehicle air conditioner of the present invention is suitable for installation in a passenger vehicle. [Explanation of symbols]

[0084] 10,110...Refrigerant circuit 11...Compressor 11a...Compressor containment vessel 12...Heater water-refrigerant heat exchanger 13…Water refrigerant heat exchanger for heat radiation 14...Air conditioning expansion device 14a...Expansion device containment vessel 15... Cooling water refrigerant heat exchanger 16...Refrigerant reservoir 50... Cooling liquid circuit 51...Air conditioning pump 52...Air cooler 60...Air conditioning unit 61...Air conditioning case 61a...Ventilation space 62...Ventilation device 63...Mixed Door 64, 65, 66...Air outlet 70,170...Heating liquid circuit 71,171...Heating pump 72,172...Air heater 80…Liquid circuit for heat radiation 81...Heat dissipation pump 82…Heat exchanger for heat radiation 83...Cooling fan 100...containment vessel 100a...Inner space of containment vessel 100au…Downward protruding space 100b...Pressure sensor 100c...gas sensor 100d...Discharge valve 100wd...Moisture recovery agent 100z...Control unit V...Vehicle VD...Dash panel VW...Front compartment air intake CR…Car interior FR…front room CH…Liquid heating device HS...Heat source part Ge: Exhaust gas M…Metal material R…Resin material

Claims

1. A vehicle air conditioning device 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 chamber (FR) and through which a flammable refrigerant circulates; a cooling liquid circuit (50) through which a liquid heat medium circulates and which absorbs heat from 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 and dissipates heat to the air taken into the front chamber (FR) by a heat dissipation heat exchanger (82); a containment vessel (100) having a containment vessel internal space (100a) formed therein; Equipped with 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 housed in the storage vessel internal space (100a), The vehicle air conditioning system has an internal space (100a) of the storage container filled with a predetermined gas from which moisture has been removed.

2. 2. The vehicle air conditioning system according to claim 1, wherein a moisture recovery agent is disposed in the storage vessel internal space.

3. The refrigerant circuit (10, 110) includes a compressor (11), the heat dissipation water-refrigerant heat exchanger (13), an air conditioning expansion device (14), and the air conditioning water-refrigerant heat exchanger (15), and is configured to circulate a refrigerant.

3. The vehicle air conditioning system according to claim 2, wherein the moisture recovery agent is disposed in a region closer to a low-pressure flow path from the air conditioning expansion device to the compressor than to a high-pressure flow path from the compressor to the air conditioning expansion device.

4. 4. The air conditioning system for a vehicle according to claim 1, wherein the internal space of the storage vessel (100a) is sealed at a pressure higher than that of the front chamber (FR).

5. 4. The air conditioning system for a vehicle according to claim 1, wherein the flammable refrigerant is propane.

6. a heating liquid circuit (170) through which a liquid heat medium circulates and which heats air supplied to the passenger compartment (CR) by an air heater (172); Equipped with 4. The vehicle air conditioning system according to claim 1, wherein the refrigerant circuit and the heating liquid circuit are thermally coupled via a heating water-refrigerant heat exchanger.

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