Vehicle air conditioning unit

Abstract

This prevents the hydrocarbon refrigerant that has leaked into the refrigerant circuit cover from separating from the odorant. [Solution] The in-vehicle air conditioning system comprises a refrigerant circuit R, a first coolant circuit, a second coolant circuit, a cover 100, and a stirring means 80. The refrigerant circuit R has a compressor, a condenser for heat dissipation, an expansion valve, and an evaporator for heat absorption, through which a hydrocarbon refrigerant mixed with an odorant circulates. The first coolant circuit has a radiator through which coolant heated by the condenser of the refrigerant circuit R circulates. The second coolant circuit has a cooler core that cools the conditioned air through which coolant cooled by the evaporator of the refrigerant circuit R circulates. The cover 100 covers the refrigerant circuit R from below. The stirring means 80 is provided inside the cover 100 and stirs the hydrocarbon refrigerant and odorant leaked from the refrigerant circuit R.

Description

Technical Field

[0001] This specification relates to an in-vehicle air conditioner, and particularly discloses an in-vehicle air conditioner using a hydrocarbon refrigerant added with an odorant.

Background Art

[0002] In recent years, use of hydrocarbon refrigerants (HC refrigerants) such as propane with a low global warming potential as a refrigerant for air conditioners has been considered. Since HC refrigerants are flammable, configurations for preventing refrigerant leakage and ensuring safety during refrigerant leakage have been studied.

[0003] Since HC refrigerants are odorless, even when refrigerant leakage occurs, it is impossible to detect the refrigerant leakage by smell. Therefore, conventionally, it has been proposed to add an odorant to the HC refrigerant used in household refrigerators and the like so that refrigerant leakage can be detected by smell.

[0004] Patent Document 1 discloses a refrigerant for air conditioning containing carbon dioxide and an odorant.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0006] In an in-vehicle air conditioner, in addition to the refrigerant circuit of the hydrocarbon refrigerant, a configuration in which at least two coolant circuits are provided can be considered.

[0007] Specifically, a refrigerant circuit is provided through which a hydrocarbon refrigerant circulates, comprising a compressor, a condenser for heat dissipation, an expansion valve, and an evaporator for heat absorption. A first coolant circuit is provided through which coolant heated by the condenser of the refrigerant circuit circulates, comprising a radiator. A second coolant circuit is provided through which coolant cooled by the evaporator of the refrigerant circuit circulates, comprising a cooler core that cools the air conditioning air. With this configuration, the hydrocarbon refrigerant circuit can be concentrated in a limited area within the vehicle body and covered with a cover. Therefore, the refrigerant circuit can be isolated from other elements of the vehicle body, thereby enhancing vehicle safety.

[0008] By adding an odorant to the hydrocarbon refrigerant used in this refrigerant circuit, even if refrigerant leaks from the refrigerant circuit to the outside through the cover, the leak can be detected by its smell.

[0009] However, if hydrocarbon refrigerant leaks from the refrigerant circuit and accumulates inside the cover, separating from the odorant, and the hydrocarbon refrigerant with a reduced odorant concentration leaks outside the cover, detection by odor may become impossible. Therefore, there is a need for technology that can suppress the separation of hydrocarbon refrigerant leaked into the refrigerant circuit cover from the odorant.

[0010] This specification discloses an in-vehicle air conditioning system that can suppress the separation of hydrocarbon refrigerant leaked into the cover of the refrigerant circuit from the odorant. [Means for solving the problem]

[0011] The in-vehicle air conditioning system disclosed herein is characterized by comprising: a refrigerant circuit having a compressor, a condenser for heat dissipation, an expansion valve, and an evaporator for heat absorption, through which a hydrocarbon refrigerant mixed with an odorant circulates; a first coolant circuit having a radiator through which a coolant heated by the condenser of the refrigerant circuit circulates; a second coolant circuit having a cooler core for cooling conditioned air through which a coolant cooled by the evaporator of the refrigerant circuit circulates; a cover covering the refrigerant circuit from below; and stirring means provided within the cover for stirring the hydrocarbon refrigerant and odorant leaked from the refrigerant circuit.

[0012] With this configuration, the hydrocarbon refrigerant and odorant that leak into the cover are stirred, which prevents the hydrocarbon refrigerant from separating from the odorant and prevents the hydrocarbon refrigerant with a reduced odorant concentration from leaking outside the cover.

[0013] In the vehicle air conditioning system of the present disclosure, the stirring means may include a rotating body that rotates within the cover to cause the hydrocarbon refrigerant and odorant within the cover to flow, and a motor that drives the rotating body.

[0014] With this configuration, since the rotating body is driven by a motor, the hydrocarbon refrigerant and odorant can be made to flow, thereby suppressing their separation.

[0015] In the in-vehicle air conditioning system of the present disclosure, the rotating body may be provided at the bottom or side wall of the cover so as to mix the hydrocarbon refrigerant and odorant that remain at the bottom of the cover.

[0016] Since hydrocarbon refrigerants and odorants are generally heavier than air, they tend to accumulate at the bottom of the cover. With the above configuration, since the rotating body is provided at the bottom or side wall of the cover, the hydrocarbon refrigerant and odorant that accumulate at the bottom of the cover can be made to flow, thereby preventing them from separating.

[0017] In the in-vehicle air conditioner of the present disclosure, it may further include a controller that controls the stirring means, and a gas sensor provided in the cover for detecting the hydrocarbon-based refrigerant. When the hydrocarbon-based refrigerant is detected by the gas sensor, the controller may drive the stirring means.

[0018] According to this configuration, when the hydrocarbon-based refrigerant in the cover is detected by the gas sensor, the stirring means is driven. Therefore, it is not necessary to drive the stirring means during normal times when the hydrocarbon-based refrigerant does not leak from the refrigerant circuit.

[0019] In the in-vehicle air conditioner of the present disclosure, the stirring means may have a moving body that can roll and move by inertial force along with acceleration or deceleration of the vehicle at the bottom of the cover.

[0020] According to this configuration, the rolling and movable moving body can make the hydrocarbon-based refrigerant and the odorant flow, suppressing their separation.

[0021] In the in-vehicle air conditioner of the present disclosure, the hydrocarbon-based refrigerant may be propane or a refrigerant mainly composed of propane.

[0022] The vehicle disclosed in this specification includes the above in-vehicle air conditioner.

Advantages of the Invention

[0023] According to the technology disclosed in this specification, it is possible to suppress the separation of the hydrocarbon-based refrigerant leaked into the cover of the refrigerant circuit from the odorant.

Brief Description of the Drawings

[0024] [Figure 1] It is a schematic diagram showing the configuration of the air conditioner. [Figure 2] It is an exploded perspective view of the cover of the refrigerant module. [Figure 3] It is a perspective view showing the refrigerant module housed in the cover body. [Figure 4]This is a cross-sectional view showing the cover, and the fan and motor used as stirring means are also shown. [Figure 5] This is a cross-sectional view showing the cover, and a sphere is shown as another means of agitation. [Figure 6] This is a cross-sectional view showing the cover, and also shows a plate material as another means of stirring. [Figure 7] This is a diagram illustrating a stirring mechanism located inside the receiver or accumulator. [Modes for carrying out the invention]

[0025] <Introduction> The embodiments will be described below with reference to the drawings. In all drawings, equivalent elements are denoted by the same reference numerals, and redundant explanations are omitted. In the following description, unless otherwise specified, terms indicating directions and orientations such as front, back, left, right, up, and down refer to directions and orientations related to the vehicle. In each figure, the arrow FR indicates the front, the arrow UP indicates upward, and the arrow LH indicates left.

[0026] The air conditioning system is installed in a vehicle such as an automobile. In the embodiments described below, the type of vehicle in which the air conditioning system is installed is not limited. For example, the vehicle may be an engine-powered automobile or an electric vehicle powered by an electric motor. The vehicle may also be a hybrid electric vehicle or a plug-in hybrid electric vehicle equipped with both an engine and an electric motor. Furthermore, the vehicle may be a fuel cell vehicle equipped with a fuel cell or a battery electric vehicle that runs on electricity stored in a battery.

[0027] The air conditioning system includes a refrigerant circuit through which a hydrocarbon refrigerant (referred to as an HC refrigerant) circulates. HC refrigerants are flammable. Examples of HC refrigerants include propane, butane, isobutane, ethane, ethylene, and propylene. In the refrigerant circuit, one of these HC refrigerants, or a mixture of two or more of these HC refrigerants, may be used. Alternatively, a mixed refrigerant may be used in the refrigerant circuit, which mainly consists of one or more HC refrigerants, as well as refrigerants other than HC refrigerants and various additives. For example, in the refrigerant circuit, propane, or a refrigerant mainly consisting of propane, containing at least one of other refrigerants and additives (a refrigerant mainly composed of propane), may be used. An example of an HC refrigerant may be R290. In this specification, hydrocarbon refrigerant (HC refrigerant) means a pure hydrocarbon refrigerant or a refrigerant mainly composed of a hydrocarbon refrigerant.

[0028] Hydrocarbon refrigerants may be mixed with (added) odorants (also called deodorants). Odorants may include, for example, sulfur compounds such as mercaptans and sulfides. The components of the odorant are not limited.

[0029] The refrigerant circuit serves as the heat source for the air conditioning system. The refrigerant circuit comprises, in order along the direction of refrigerant flow, a compressor, a condenser for heat dissipation, an expansion valve, and an evaporator for heat absorption. A receiver may be provided between the condenser and the expansion valve. An accumulator may also be provided between the evaporator and the compressor.

[0030] An air conditioning system may include a high-temperature coolant circuit through which a coolant heated by a condenser in the refrigerant circuit circulates, and a low-temperature coolant circuit through which a coolant cooled by an evaporator in the refrigerant circuit circulates. The coolant is a heat transfer medium, and the high-temperature coolant circuit and the low-temperature coolant circuit are heat transfer medium circuits, respectively.

[0031] In the embodiment described below, as shown in Figure 1, the air conditioning system 12 includes a first coolant circuit C1 as a high-temperature coolant circuit and second and third coolant circuits C2 and C3 as low-temperature coolant circuits.

[0032] The coolant in the first to third coolant circuits C1, C2, and C3 may be coolant water. That is, the coolant may be water without additives, water mixed with additives such as antifreeze or preservatives, or coolant fluid. Furthermore, the coolant may also be a liquid heat transfer medium such as oil, and is not limited to that.

[0033] In the embodiments described below, the refrigerant circuit is located under the vehicle's front hood. Hereafter, regardless of the presence or type of power source (engine, motor, etc.) under the front hood, the area under the front hood will be referred to as the "engine room".

[0034] <Embodiment> Figure 1 is a schematic diagram showing the configuration of an air conditioning system 12 according to an embodiment. The air conditioning system 12 is mounted on an electric vehicle. This electric vehicle may be an automobile equipped with a battery 54 that supplies power to a motor as a power source, such as a battery electric vehicle, a hybrid electric vehicle, or a plug-in hybrid electric vehicle.

[0035] The air conditioning unit 12 provides air conditioning to the vehicle's interior and also cools the battery 54. The air conditioning unit 12 may also be configured to cool other in-vehicle equipment, such as a PCU (Power Control Unit), either together with or instead of the battery 54.

[0036] As shown in Figure 1, the air conditioning system 12 comprises a refrigerant circuit R which serves as a heat source, first to third coolant circuits C1, C2, and C3, and an air conditioning unit 70. The first coolant circuit C1 circulates a first coolant heated by the refrigerant in the refrigerant circuit R. The second coolant circuit C2 circulates a second coolant cooled by the refrigerant in the refrigerant circuit R. Similarly, the third coolant circuit C3 circulates a third coolant cooled by the refrigerant in the refrigerant circuit R. The air conditioning unit 70 supplies air cooled by the second coolant circulating in the second coolant circuit C2 into the vehicle cabin.

[0037] The refrigerant circuit R is a closed circuit that circulates an HC-based refrigerant (hereinafter also simply referred to as refrigerant), and is configured by sequentially connecting a compressor 20, a condenser 22, a receiver 28, expansion valves 24a and 24b, and evaporators 26a and 26b by refrigerant piping. An accumulator 29 (shown by a dashed line in Figure 1) may be provided between the evaporators 26a and 26b and the compressor 20. The expansion valve 24a and evaporator 26a are connected in series, and similarly, the expansion valve 24b and evaporator 26b are connected in series. The refrigerant flow paths of the expansion valve 24a and evaporator 26a and the refrigerant flow paths of the expansion valve 24b and evaporator 26b are connected in parallel.

[0038] The refrigerant in refrigerant circuit R is mixed with an odorant. Therefore, if refrigerant leaks from refrigerant circuit R, a person can detect the leak by its smell.

[0039] The air conditioning unit 12 includes a heat exchanger 30. The heat exchanger 30 is integrated with the condenser 22 of the refrigerant circuit R and exchanges heat between the refrigerant of the refrigerant circuit R and the first coolant of the first coolant circuit C1. The heat exchanger 30 is a water-cooled condenser and may be, for example, a plate heat exchanger.

[0040] The first coolant circuit C1 is a closed circuit that circulates the first coolant, consisting of a water pump 32, a heat exchanger 30, and a radiator 34 connected sequentially by coolant piping. The radiator 34 is a heat exchanger that exchanges heat between the first coolant and the vehicle's airflow Wtr. In the first coolant circuit C1, the first coolant, pressurized by the water pump 32, becomes hot due to heat dissipation from the refrigerant in the condenser 22 of the refrigerant circuit R as it passes through the heat exchanger 30. The hot first coolant is then sent to the radiator 34, where it is cooled by the vehicle's airflow Wtr.

[0041] Furthermore, the air conditioning unit 12 includes a heat exchanger 40. The heat exchanger 40 is integrated with the evaporator 26a of the refrigerant circuit R and exchanges heat between the refrigerant of the refrigerant circuit R and the second coolant of the second coolant circuit C2. The heat exchanger 40 may be, for example, a plate heat exchanger.

[0042] The second coolant circuit C2 is a closed circuit that circulates the second coolant, with the water pump 42, heat exchanger 40, and cooler core 72 sequentially connected by coolant piping. The cooler core 72 is a heat exchanger located in the air passage 75 of the air conditioning unit 70, which exchanges heat between the second coolant and the conditioned air (Wac). In the second coolant circuit C2, the second coolant, pressurized by the water pump 42, becomes cold due to the heat absorption of the refrigerant in the evaporator 26a of the refrigerant circuit R as it passes through the heat exchanger 40. The cold second coolant is then sent to the cooler core 72, where it cools the conditioned air (Wac).

[0043] Furthermore, the air conditioning unit 12 includes a heat exchanger 50. The heat exchanger 50 is integrated with the evaporator 26b of the refrigerant circuit R and exchanges heat between the refrigerant of the refrigerant circuit R and the third coolant of the third coolant circuit C3. The heat exchanger 50 may be, for example, a plate heat exchanger.

[0044] The third coolant circuit C3 is a closed circuit that circulates the third coolant, with the water pump 52, heat exchanger 50, and battery 54 sequentially connected by coolant piping. In the third coolant circuit C3, the coolant pumped by the water pump 52 becomes cold due to the absorption of heat by the refrigerant in the evaporator 26b in the refrigerant circuit R as it passes through the heat exchanger 50. The cold third coolant is then sent to the battery 54 to cool the battery 54.

[0045] In the refrigerant circuit R, the refrigerant circulates as follows: The compressor 20 discharges high-pressure gaseous refrigerant, which dissipates heat and liquefies and condenses in the condenser 22 by exchanging heat with the first coolant of the first coolant circuit C1, which passes through the heat exchanger 30, becoming high-pressure liquid refrigerant. The high-pressure liquid refrigerant flowing out of the condenser 22 is depressurized and expanded by the expansion valve 24a via the receiver 28, becoming low-pressure refrigerant, and flows into the evaporator 26a. The low-pressure refrigerant flowing into the evaporator 26a evaporates by exchanging heat with the second coolant of the second coolant circuit C2, which passes through the heat exchanger 40, becoming gaseous refrigerant, flowing out of the evaporator 26a, and returning to the compressor 20.

[0046] Furthermore, the high-pressure liquid refrigerant flowing out of the condenser 22 is depressurized and expanded by the expansion valve 24b via the receiver 28, becoming low-pressure refrigerant, and flows into the evaporator 26b. The low-pressure refrigerant flowing into the evaporator 26b evaporates by exchanging heat with the third coolant in the third coolant circuit C3 that passes through the heat exchanger 50, becoming gaseous refrigerant, flowing out of the evaporator 26b, and returning to the compressor 20.

[0047] The air conditioning unit 70 comprises a blower 76 and an air passage 75 formed by a case (not shown). Inside the air passage 75, the blower 76, a cooler core 72, and a heater core 74 are arranged in order from the direction of airflow. The heater core 74 is a heat exchanger to which, for example, engine coolant or coolant heated by a PTC heater for water heating is supplied. The heater core 74 may also be configured to be supplied with coolant heated by the heat exchanger 30.

[0048] The blower 76 introduces air into the air passage 75 from an air intake (not shown) and blows this air through the cooler core 72 and heater core 74, thereby supplying temperature-controlled air to the passenger compartment. An air mix door 78 is provided inside the air passage 75, and the air mix door 78 adjusts the ratio of air that has passed through the cooler core 72 to that which flows to the heater core 74. The air conditioning unit 70 may employ conventional HVAC (Heating, Ventilation, and Air Conditioning) technology.

[0049] The air conditioning unit 70 is located, for example, between the instrument panel and the dashboard in a vehicle. The battery 54 is located, for example, under the floor of the passenger compartment, i.e., under the floor panel.

[0050] The air conditioning unit 12 includes a controller. The controller may consist of a processor and a memory device, and may be, for example, an ECU (Electronic Control Unit). The controller controls the equipment included in the air conditioning unit 12 based on detection information from multiple sensors (a temperature sensor that detects the outside temperature, inside temperature, battery temperature (temperature of the battery 54), a solar radiation sensor, a pressure sensor (a sensor that detects the pressure in the piping), etc.), and setting information from an operation panel operated by the user. The controller may employ conventional air conditioning control technology. This controller may be the same as the controller 110 shown in Figure 4, which will be described later, or it may be a different one.

[0051] The refrigerant circuit R is integrated to form a refrigerant module RM, as shown in the upper right of Figure 2. Specifically, the refrigerant module RM is a unit that integrates the equipment (components) of the air conditioning unit 12 located inside the dashed line in Figure 1. As shown in Figure 2, the refrigerant module RM consists of a compressor 20, the first to third heat exchangers 30, 40, and 50, a receiver 28, and two expansion valves 24a and 24b, which are fixed to the upper surface of a plate 150 by screws or the like. The equipment is connected to each other by refrigerant piping 152.

[0052] The air conditioning unit 12 includes a cover 100, as shown in Figure 2. The cover 100 includes a cover body 102 and a top panel 103. The refrigerant module RM is housed inside the cover body 102, as shown in Figure 3. The refrigerant module RM is fixed to the inner surface of the cover body 102 via a bracket (not shown). The top panel 103 is attached to the cover body 102 so as to cover the cover body 102 in which the refrigerant module RM is housed.

[0053] The cover 100 and the refrigerant module RM are located in the engine compartment of the vehicle. The cover 100 is located, for example, behind the front end of the drive unit (engine unit, motor unit, powertrain unit including engine and transaxle, or e-axle, etc.) and above the drive unit.

[0054] The cover body 102 has an outer surface that provides heat insulation. Heat insulation may be achieved by forming the cover body 102 itself with a heat-insulating material, or by applying aluminum vapor deposition, aluminum foil, etc., to the outer surface of the cover body 102. As shown in Figure 2, the cover body 102 includes a front wall 112, a rear wall 114, a left side wall 116, a right side wall 117, and a bottom wall 118. The outer surfaces of these walls provide heat insulation. The cover body 102 also has a flange 130 that protrudes outward at its upper end. The flange 130 has a frame shape when viewed from above.

[0055] As shown in Figure 3, the left wall 116 has two through holes 136a and 136b for passing the piping of the first coolant circuit C1. The right wall 117 has two through holes 136c and 136d for passing the piping of the second coolant circuit C2, and two through holes 136e and 136f for passing the piping of the third coolant circuit C3. One or more walls of the cover body 102 may have holes (not shown) for passing electrical wires such as power lines and control lines connected to equipment such as the compressor 20.

[0056] The bottom wall 118 of the cover body 102 is provided with a hole 140, as shown in Figure 2. A hose 142 extending downwards from the vehicle is connected to this hole 140. The hose 142 extends from the hole 140 in the bottom wall 118 toward the bottom of the vehicle body. The end of the hose 142 (not shown) may be fixed to a vehicle body structure located at the lower (or bottom) of the engine compartment.

[0057] This hose 142 allows, in the event that HC-based refrigerant leaks from the refrigerant circuit R into the cover 100, to be guided downwards through the hose 142. Since HC-based refrigerant is generally heavier than air, it flows downwards through the hose 142. This allows the HC-based refrigerant to be released to a relatively safe location at the bottom of the vehicle.

[0058] The top panel 103 also has an outer surface that provides heat insulation. Heat insulation may be achieved by forming the top panel 103 itself with a heat-insulating material, or by applying aluminum vapor deposition, aluminum foil, etc., to the outer surface of the top panel 103. The top panel 103 is positioned on the flange 130 of the cover body 102. The outer periphery of the top panel 103 is fastened to the flange 130 of the cover body 102 by multiple screws.

[0059] According to this embodiment, the refrigerant circuit R of the HC-based refrigerant can be concentrated in a limited area within the vehicle body and covered by the cover 100. Therefore, the refrigerant circuit R can be isolated from other elements of the vehicle body, thereby enhancing the safety of the vehicle.

[0060] The cover 100 may be constructed without the top panel 103. The top panel 103 may also have an opening. Furthermore, the cover 100 does not need to have heat-shielding properties. The cover 100, in whole or in part, may be made of metal, resin, or the like.

[0061] Furthermore, another air conditioning system may be constructed by omitting the expansion valve 24b, heat exchanger 50, and third coolant circuit C3 from the above-mentioned air conditioning system 12 (see Figure 1). This air conditioning system can be used in vehicles such as engine-powered vehicles that do not have a battery 54 (a battery that supplies power to the motor).

[0062] Furthermore, the refrigerant circuit R does not necessarily have to be fixed to the plate 150 (Figure 2) as described above. In other words, the refrigerant circuit R only needs to be housed inside the cover 100. For example, the multiple components constituting the refrigerant circuit R may be individually fixed to the inner surface of the cover 100.

[0063] <Stirring means> Figure 4 is a cross-sectional view showing a cross-section of the cover 100. The air conditioning unit 12 is equipped with a fan 80 and a motor 81 as stirring means. Although two sets of fan 80 and motor 81 are shown in Figure 4, the air conditioning unit 12 may be equipped with one set or three or more sets of fan 80 and motor 81.

[0064] The fan 80 is a rotating body and is located inside the cover 100. The fan rotation shaft that rotates the fan 80 passes through a hole in the wall of the cover body 102 and is connected to the drive shaft of a motor 81 located outside the cover body 102. The fan 80 may be located at the bottom of the cover body 102, as shown in Figure 4. Alternatively, the fan 80 may be located on the side wall (inner wall) of the cover body 102, near the bottom of the cover body 102, as shown in the same figure.

[0065] The air conditioning unit 12 includes a gas sensor 96 and a controller 110. The gas sensor 96 is located inside the cover 100 and detects HC-based refrigerants. The gas sensor 96 is located, for example, near the bottom of the cover body 102. The controller 110 includes a processor and a memory device and controls the motor 81. The detection signal from the gas sensor 96 is input to the controller 110.

[0066] The controller 110 turns on (drives) the motor 81 when the gas sensor 96 detects an HC-based refrigerant, thereby rotating the fan 80. The controller 110 then turns off the motor 81 and stops the fan 80 when the gas sensor 96 no longer detects an HC-based refrigerant. Alternatively, the controller 110 may turn off the motor 81 and stop the fan 80 after a predetermined time has elapsed since the gas sensor 96 stopped detecting an HC-based refrigerant.

[0067] According to this embodiment, if HC-based refrigerant leaks from the refrigerant circuit R into the cover 100, the fan 80 agitates the HC-based refrigerant and the odorant, thereby preventing the HC-based refrigerant from separating from the odorant. This also prevents the HC-based refrigerant, with its reduced odorant concentration, from leaking outside the cover 100. As a result, a person can detect a refrigerant leak by its smell.

[0068] Since HC-based refrigerants and odorants are generally heavier than air, they tend to accumulate at the bottom of the cover 100. In this embodiment, since the fan 80 is provided at the bottom or side wall of the cover 100, the HC-based refrigerant and odorant that accumulate at the bottom of the cover 100 can be circulated, thereby preventing them from separating.

[0069] Furthermore, since the controller 110 rotates the fan 80 when the gas sensor 96 detects HC-based refrigerant, the fan 80 does not need to be rotated during normal operation when no HC-based refrigerant is leaking from the refrigerant circuit R. This reduces the amount of electrical energy consumed by the motor 81.

[0070] The controller 110 may turn on the motor 81 and rotate the fan 80 while the compressor 20 of the refrigerant circuit R is operating. In other words, the controller 110 may rotate the fan 80 in conjunction with the operation of the compressor 20. When the compressor 20 of the refrigerant circuit R is not operating, the controller 110 turns off the motor 81 and stops the fan 80.

[0071] Furthermore, the controller 110 may switch the motor 81 on and off at predetermined intervals. That is, the controller 110 may periodically turn on the motor 81 to rotate the fan 80.

[0072] <Another stirring method> Figure 5 shows a sphere 84 as an alternative stirring means. In this configuration, a sphere 84 is used as a moving body instead of a fan 80 and a motor 81 to stir the HC-based refrigerant and odorant.

[0073] A sphere 84 is housed at the bottom of the cover body 102. There may be one sphere 84 or multiple spheres. The sphere 84 rolls around at the bottom of the cover body 102 due to inertia as the vehicle accelerates or decelerates. To prevent the sphere 84 from falling into the hole 140 of the cover body 102, a stopper 94, which is a wall protruding upward from the edge of the hole 140, is provided. According to this embodiment, the sphere 84 can cause the HC-based refrigerant and the odorant to flow together, thereby suppressing their separation.

[0074] Although Figure 5 illustrates a simple sphere 84, the surface of the sphere 84 may have irregularities added to it. Alternatively, the sphere 84 may be hollow, with a portion of its surface cut out. In other words, the shape of the sphere 84 may be modified, or parts may be added to its surface to enhance the stirring effect associated with the rotation of the sphere 84. Furthermore, the moving body is not limited to the sphere 18, but can be any object that can roll and move in conjunction with the acceleration or deceleration of the vehicle. The moving body may be, for example, a cylindrical or cylindrical object.

[0075] <Further stirring means> Figure 6 shows a plate material 86 as yet another stirring means. In the same figure, the plate material 86 is shown enlarged due to the blowing. In this configuration, the plate material 86 is used instead of the fan 80 and motor 81 to stir the HC-based refrigerant and odorant.

[0076] A plate 86 is pivotably mounted on the bottom of the cover body 102. There may be one plate 86 or multiple plates. A pivot point 88 is provided on the bottom of the cover body 102. The end of the plate 86 is pivotably attached to the pivot point 88. For example, the pivot point 88 can be formed by two shaft members fixed to the bottom of the cover body 102, and the two shaft members can be inserted into holes in the end of the plate 86 to make the plate 86 pivotable. In that case, a rotatable disc may be provided between the two shaft members and the bottom of the cover body 102 so that the two shaft members can rotate relative to the bottom of the cover body 102.

[0077] Alternatively, the pivot point 88 may be composed of a hemispherical outer shell fixed to the bottom of the cover body 102 and a sphere inserted inside the outer shell. A window may be provided at the top of the outer shell, and the plate material 86 and the sphere inside the outer shell may be connected through the window, allowing the plate material 86 to swing in the front, back, left, right, or any direction.

[0078] The plate material 86 oscillates at the bottom of the cover body 102 due to inertial force as the vehicle accelerates or decelerates. This causes the HC-based refrigerant and odorant to flow, suppressing their separation.

[0079] <Another embodiment> In the embodiment described above, the refrigerant module RM is housed inside the cover 100, and stirring means for stirring the HC-based refrigerant and odorant are provided inside the cover 100. However, stirring means for stirring the HC-based refrigerant and odorant may be provided inside the receiver 28 or accumulator 29 of the refrigerant circuit R. In this case, the refrigerant circuit R may or may not be housed inside the cover 100.

[0080] Figure 7 is a schematic cross-sectional view of the receiver 28 or accumulator 29, with internal piping and other structures omitted. The following explanation will use the receiver 28 as an example, but a similar configuration can be applied to the accumulator 29.

[0081] The air conditioning unit 12 is equipped with a fan 90 and a motor 91 as a means of stirring. Although two sets of fan 90 and motor 91 are shown in Figure 7, the air conditioning unit 12 may be equipped with one set or three or more sets of fan 90 and motor 91.

[0082] The fan 90 is a rotating body and is located inside the receiver 28. The fan's rotating shaft, which rotates the fan 90, passes through a hole in the wall of the receiver 28 and is connected to the drive shaft of a motor 91 located outside the receiver 28. The fan 90 may be located on the ceiling of the receiver 28 to agitate the gaseous refrigerant GR inside the receiver 28, as shown in Figure 7. Alternatively, the fan 90 may be located at the bottom of the receiver 28 to agitate the liquid refrigerant LR inside the receiver 28, as shown in the same figure. The fan 90 may also be located on the side wall (inner wall) of the receiver 28.

[0083] The air conditioning unit 12 includes a controller (not shown) which comprises a processor and a memory device. The controller controls the motor 91. For example, the controller turns on the motor 91 to rotate the fan 90 while the compressor 20 of the refrigerant circuit R is operating. Alternatively, the controller may switch the motor 91 on and off at a predetermined interval. That is, the controller may periodically turn on the motor 91 to rotate the fan 90.

[0084] In this embodiment, the HC-based refrigerant and odorant are agitated by the fan 90 within the receiver 28, thereby suppressing the separation of the HC-based refrigerant from the odorant. In the event that HC-based refrigerant leaks from the refrigerant circuit R, the leakage of HC-based refrigerant with a reduced odorant concentration outside the refrigerant circuit R can be suppressed. Therefore, a person can detect a refrigerant leak by the smell of the refrigerant.

[0085] The stirring mechanism inside the receiver 28 may be a spherical body 84 (moving body) as described in Figure 5, or a plate 86 as described in Figure 6, instead of the fan 90 and motor 91. The pivot point 88 of the plate 86 may be provided on the ceiling of the receiver 28. [Explanation of Symbols]

[0086] 12 Air conditioning unit, 20 Compressor, 22 Condenser, 24a Expansion valve (Air conditioning expansion valve), 24b Expansion valve (Battery expansion valve), 26a Evaporator (Air conditioning evaporator), 26b Evaporator (Battery evaporator), 28 Receiver, 29 Accumulator, 30 Heat exchanger (First heat exchanger), 32 Water pump, 34 Radiator, 40 Heat exchanger (Second heat exchanger, Air conditioning heat exchanger), 42 Water pump, 50 Heat exchanger (Third heat exchanger, Battery heat exchanger), 52 Water pump, 54 Battery, 70 Air conditioning unit, 72 Cooler core, 74 Heater core, 75 Air passage, 76 Blower, 78 Air mix door, 80 Fan (Rotating body), 81 Motor, 84 Sphere, 86 Plate material, 88 90 Pivot point, 91 Fan (rotating body), 94 Motor, 96 Stopper, 96 Gas sensor, 100 Cover, 102 Cover body, 103 Top panel, 112 Front wall, 114 Rear wall, 116 Left side wall, 117 Right side wall, 118 Bottom wall, 130 Flange, 136a~136f Through hole, 140 Hole, 142 Hose, 150 Plate, 152 Refrigerant piping, R Refrigerant circuit, RM Refrigerant module, C1 First coolant circuit, C2 Second coolant circuit (Air conditioning coolant circuit), C3 Third coolant circuit (Battery coolant circuit), Wtr Driving airflow, Wac Air conditioning airflow, GR Gas refrigerant, LR Liquid refrigerant.

Claims

1. In-vehicle air conditioning system, A refrigerant circuit comprising a compressor, a condenser for heat dissipation, an expansion valve, and an evaporator for heat absorption, through which a hydrocarbon refrigerant mixed with an odorant circulates, The coolant heated by the condenser of the refrigerant circuit circulates to a first coolant circuit having a radiator, A second coolant circuit having a cooler core in which the coolant cooled by the evaporator of the refrigerant circuit circulates to cool the air conditioning air, A cover that covers the refrigerant circuit from below, The cover is provided with a stirring means for stirring the hydrocarbon refrigerant and odorant leaked from the refrigerant circuit, In-vehicle air conditioner.

2. An in-vehicle air conditioning system according to claim 1, The stirring means is A rotating body that rotates within the cover to cause the hydrocarbon refrigerant and odorant within the cover to flow, A motor that drives the rotating body, In-vehicle air conditioner.

3. An in-vehicle air conditioning system according to claim 2, The rotating body is provided on the bottom or side wall of the cover to mix the hydrocarbon refrigerant and odorant that remain at the bottom of the cover. In-vehicle air conditioner.

4. An in-vehicle air conditioning system according to any one of claims 1 to 3, A controller that controls the stirring means, The cover further comprises a gas sensor provided within the cover for detecting the hydrocarbon refrigerant, The aforementioned controller, When the hydrocarbon refrigerant is detected by the gas sensor, the stirring means is driven. In-vehicle air conditioner.

5. An in-vehicle air conditioning system according to claim 1, The stirring means has a movable body at the bottom of the cover that can roll and move due to inertial force in response to the acceleration or deceleration of the vehicle. In-vehicle air conditioner.

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