Vehicle air conditioning unit

Abstract

The refrigerant circuit for hydrocarbon refrigerants is isolated from heat-generating elements within the vehicle body. [Solution] The on-board air conditioning system comprises a refrigerant circuit R and first and second coolant circuits C1 and C2. The refrigerant circuit R has a compressor 20, a condenser for heat dissipation, an expansion valve 24a, and an evaporator for heat absorption, through which a hydrocarbon refrigerant circulates. A first heat exchanger 30 is integrally configured with the condenser of the refrigerant circuit R and transfers heat from the refrigerant in the condenser to the coolant of the first coolant circuit C1. The first coolant circuit C1 has a radiator. A second heat exchanger 40 is integrally configured with the evaporator of the refrigerant circuit R and cools the coolant of the second coolant circuit C2 with the refrigerant in the evaporator. The second coolant circuit C2 has a cooler core located in the air conditioning unit. The on-board air conditioning system comprises a heat shield plate 100 positioned between the refrigerant circuit R and the first and second heat exchangers 30 and 40 and a heat-generating element 14 mounted on the vehicle.

Description

Technical Field

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

Background Art

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

[0003] Patent Document 1 discloses a cooling device for a drive device with a motor, which includes an oil circulation system for cooling the motor and a water circulation system for cooling the oil by heat exchange.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] In a vehicle, there are heat-generating elements such as an engine, a motor, an inverter, and a battery. Also, in a vehicle, there are wire connection parts such as power terminals of a battery, connectors of electrical equipment, and connectors between wires. At a wire connection part, it is conceivable that a spark may occur due to poor contact between two electrically conductive parts. In an in-vehicle air conditioner, it is desired to isolate the refrigerant circuit of the hydrocarbon refrigerant from the heat-generating elements or wire connection parts inside the vehicle body to enhance the safety of the vehicle.

[0006] Therefore, this specification discloses an in-vehicle air conditioner that isolates the refrigerant circuit of the hydrocarbon refrigerant from the heat-generating elements or wire connection parts inside the vehicle body.

Means for Solving the Problems

[0007] The in-vehicle air conditioning system disclosed herein is characterized by comprising: a refrigerant circuit through which a hydrocarbon refrigerant circulates, having a compressor, a condenser for heat dissipation, an expansion valve, and an evaporator for heat absorption; a first heat exchanger integrated with the condenser of the refrigerant circuit, which transfers heat from the refrigerant in the condenser to a first coolant; a first coolant circuit through which the first coolant circulates, having a radiator; a second heat exchanger integrated with the evaporator of the refrigerant circuit, which cools a second coolant with the refrigerant in the evaporator; a second coolant circuit through which the second coolant circulates, having a cooler core; an air conditioning unit having an air passage in which the cooler core is located, which cools the air passing through the air passage and blows it into the passenger compartment; and a heat shield plate disposed between the refrigerant circuit, the first and second heat exchangers, and a heat-generating element disposed in the vehicle.

[0008] In this configuration, the refrigerant circuit dissipates heat to the first coolant of the first coolant circuit and absorbs heat to the second coolant of the second coolant circuit. This allows the refrigerant circuit to be concentrated in a relatively small area within the vehicle, and the refrigerant circuit and the first and second heat exchangers to be isolated from the heat-generating elements by a heat shield. Since the heat shield blocks radiant heat from the heat-generating elements, the heating of the refrigerant circuit due to that heat can be suppressed. Furthermore, in the event that hydrocarbon refrigerant leaks from the refrigerant circuit, the heat shield can prevent that refrigerant from flowing out to the heat-generating elements.

[0009] In the vehicle air conditioning system of this disclosure, the refrigerant circuit and the first and second heat exchangers may be arranged above the heat-generating element, the heat shield may be inclined downward toward one side, and the lower end of the heat shield may be located outside the heat-generating element.

[0010] Hydrocarbon refrigerants are generally heavier than air. Therefore, with the above configuration, if a hydrocarbon refrigerant leaks from the refrigerant circuit, the refrigerant can be caught on the upper surface of the heat shield, flowed along the downward direction of the heat shield, and guided to the outside of the heat-generating element from the lower end of the heat shield.

[0011] In the vehicle air conditioning system of the present disclosure, the heat-generating element may include a high-temperature portion and a low-temperature portion that is at a lower temperature, and the heat shield may include an upper portion located above the high-temperature portion of the heat-generating element and a lower portion located at a lower position than the upper portion and above the low-temperature portion of the heat-generating element.

[0012] With this configuration, if hydrocarbon refrigerant leaks from the refrigerant circuit, the refrigerant can be received on the upper surface of the heat shield and guided from the upper part of the heat shield, which can become hot, to the lower part, which can become colder.

[0013] In the vehicle air conditioning system of the present disclosure, the refrigerant circuit and the first and second heat exchangers are arranged above the heat-generating element, and the heat shield plate may include two opposing sides having an upwardly projecting edge and at least one side located outside the heat-generating element and lacking the edge.

[0014] With this configuration, if hydrocarbon refrigerant leaks from the refrigerant circuit, the protruding edge of the heat shield can prevent the refrigerant from flowing down from the heat shield to the heat-generating element. In addition, the refrigerant can be guided to the outside of the heat-generating element through the side of the heat shield where the protruding edge is omitted.

[0015] Furthermore, the in-vehicle air conditioning system disclosed herein is characterized by comprising: a refrigerant circuit through which a hydrocarbon refrigerant circulates, having a compressor, a condenser for heat dissipation, an expansion valve, and an evaporator for heat absorption; a first heat exchanger integrated with the condenser of the refrigerant circuit, which transfers heat from the refrigerant in the condenser to a first coolant; a first coolant circuit through which the first coolant circulates, having a radiator; a second heat exchanger integrated with the evaporator of the refrigerant circuit, which cools a second coolant with the refrigerant in the evaporator; a second coolant circuit through which the second coolant circulates, having a cooler core; an air conditioning unit having an air passage in which the cooler core is located, which cools the air passing through the air passage and blows it into the passenger compartment; and a partition plate disposed between the refrigerant circuit and the first and second heat exchangers and an electrical wiring connection part located inside the vehicle.

[0016] With this configuration, in the event that hydrocarbon-based refrigerant leaks from the refrigerant circuit, the partition plate can prevent the refrigerant from flowing out to the electrical wiring connection.

[0017] In the vehicle air conditioning system of this disclosure, the hydrocarbon refrigerant may be propane or a refrigerant mainly composed of propane.

[0018] The vehicles disclosed herein are equipped with the above-described on-board air conditioning system. [Effects of the Invention]

[0019] The technology disclosed herein allows for the isolation of a hydrocarbon refrigerant circuit from heat-generating elements or electrical wiring connections within the vehicle body. [Brief explanation of the drawing]

[0020] [Figure 1] This is a schematic diagram showing the configuration of an air conditioning system. [Figure 2] This is a schematic diagram showing the layout of the air conditioning system inside the vehicle. [Figure 3] This is a perspective view illustrating the location of the refrigerant module inside the vehicle. [Figure 4]It is a perspective view showing a heat shield and the structures around it. [Figure 5] It is a perspective view showing another heat shield and the structures around it. [Figure 6] It is a perspective view showing yet another heat shield and the structures around it. [Figure 7] It is a schematic diagram showing the configuration of another air conditioner.

Embodiments for Carrying out the Invention

[0021] <Preface> Hereinafter, embodiments will be described with reference to the drawings. In all the drawings, the same reference numerals are assigned to equivalent elements, and duplicate descriptions will be omitted. In the following description, unless otherwise specified, the terms indicating directions and orientations such as front, rear, left, right, up, and down represent the directions and orientations related to the vehicle. In each figure, the direction of arrow FR represents the front, the direction of arrow UP represents the up, and the direction of arrow LH represents the left.

[0022] The air conditioner is mounted on a vehicle such as an automobile. In each of the embodiments described below, the type of vehicle on which the air conditioner is mounted is not limited. For example, the vehicle may be an engine vehicle powered by an engine, or an electric vehicle powered by a motor. Also, the vehicle may be a hybrid electric vehicle or a plug-in hybrid electric vehicle equipped with both an engine and a motor. Further, the vehicle may be a fuel cell vehicle equipped with a fuel cell, or a battery electric vehicle that runs on electric power stored in a battery.

[0023] 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.

[0024] 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.

[0025] 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.

[0026] In the embodiments 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. The air conditioning system 12 can be configured without the third coolant circuit C3, which will be explained with reference to Figure 7.

[0027] 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.

[0028] 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".

[0029] <Embodiment> Figure 1 is a schematic diagram showing the configuration of the air conditioning system 12 according to an embodiment. Figure 2 is a schematic diagram showing the arrangement of the air conditioning system 12 inside the vehicle. The vehicle 10 is equipped with a battery 54 that supplies power to a motor as a power source. The vehicle 10 may be, for example, a battery electric vehicle, a hybrid electric vehicle, a plug-in hybrid electric vehicle, etc.

[0030] The air conditioning unit 12 provides air conditioning to the vehicle compartment 90 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), along with the battery 54, or in place of the battery 54.

[0031] 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.

[0032] The refrigerant circuit R is a closed circuit that circulates an HC-based refrigerant (hereinafter also simply referred to as refrigerant) by sequentially connecting a compressor 20, a condenser 22, a receiver 28, expansion valves 24a and 24b, and evaporators 26a and 26b via refrigerant piping. 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.

[0033] 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. The heat exchanger 30 is the first heat exchanger.

[0034] 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.

[0035] 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. The heat exchanger 40 is the second heat exchanger.

[0036] 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).

[0037] 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. The heat exchanger 50 is the third heat exchanger.

[0038] 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 it. In this specification, the third coolant circuit C3 and the third coolant are also referred to as the battery coolant circuit and the battery coolant, respectively.

[0039] In this specification, the expansion valve 24a, evaporator 26a, and heat exchanger 40 are also referred to as the air conditioning expansion valve, air conditioning evaporator, and air conditioning heat exchanger, respectively. Furthermore, the expansion valve 24b, evaporator 26b, and heat exchanger 50 are also referred to as the battery expansion valve, battery evaporator, and battery heat exchanger, respectively.

[0040] 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.

[0041] 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.

[0042] The air conditioning unit 70 comprises a blower 80 and an air passage 75 formed by a case (not shown). Inside the air passage 75, the blower 80, 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.

[0043] The blower 80 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 82 is provided inside the air passage 75, which 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.

[0044] As shown in Figure 2, the engine compartment 92 and the passenger compartment 90 are separated by a dashboard 94. An instrument panel (not shown) is provided on the passenger compartment 90 side of the dashboard 94. The air conditioning unit 70 is located between the instrument panel and the dashboard 94.

[0045] The battery 54 is located under the floor of the passenger compartment 90, that is, under the floor panel 96. However, the battery 54 may also be located under the seats or at the rear of the vehicle, and its location is not limited.

[0046] 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 (temperature sensors that detect outside temperature, inside temperature, and battery temperature, solar radiation sensors, pressure sensors, etc.), and setting information from an operation panel operated by the user. The controller may employ conventional air conditioning control technology.

[0047] As shown in Figure 4, the refrigerant circuit R is integrated to form a refrigerant module RM. 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 4, 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.

[0048] The refrigerant module RM is located in the engine compartment 92, as shown in Figure 2. The first coolant circuit C1 is located in front of the refrigerant module RM. The refrigerant module RM may be located behind the collision deformation region at the front of the vehicle. This reduces the collision load input to the refrigerant module RM (refrigerant circuit R) when the vehicle 10 is involved in a head-on collision.

[0049] Figure 3 shows the more specific location of the refrigerant module RM. The vehicle 10 is equipped with a drive unit 14. The drive unit 14 consists of a power source for the vehicle 10 and a structure integrated therewith. The power source may include an engine, a motor, or both. The drive unit 14 may be, for example, an engine unit, a motor unit, a powertrain unit including an engine and a transaxle, or an eAxle. The drive unit 14 is located in the engine compartment 92.

[0050] As shown in Figure 3, the refrigerant module RM is positioned behind the front end 14F of the drive unit 14 and above the drive unit 14. A heat shield 100 is positioned between the refrigerant module RM and the drive unit 14. The area behind the front end 14F of the drive unit 14 is a protected space during a head-on collision of the vehicle 10. By positioning the refrigerant module RM in this space, the collision load input to the refrigerant module RM (refrigerant circuit R) during a head-on collision of the vehicle 10 can be reduced.

[0051] Figure 4 is a perspective view showing the heat shield 100 and the surrounding structure, and the outlet in the upper left of the figure shows their general configuration. Note that inside the dashed line in the lower left of the figure is another embodiment ( The partition plate 101) of the wire connection section 15 is shown, and this diagram will be explained later.

[0052] The refrigerant module RM is located above the drive unit 14. The drive unit 14 is an example of a heat-generating element. The heat shield 100 is located between the refrigerant module RM and the drive unit 14. The refrigerant module RM and the heat shield 100 are each held to a structure in the engine compartment 92 via brackets (not shown).

[0053] The heat shield 100 has a rectangular shape when viewed from above. The refrigerant module RM is located inside the heat shield 100 when viewed from above. The heat shield 100 has a front edge 130F, a rear edge 130B, a left edge 130L, and a right edge 130R. The heat shield 100 slopes downward toward the right. The heat shield 100 has an upwardly projecting edge 110 on the opposing front edge 130F and rear edge 130B and on the left edge 130L. The right edge 130R of the heat shield 100 is the lower end 105 of the heat shield 100, and the upwardly projecting edge 110 is omitted. The lower end 105 of the heat shield 100 is located outside the drive unit 14.

[0054] The heat shielding performance of the heat shield plate 100 is obtained by forming the plate itself with a heat shielding material. Alternatively, the heat shielding performance of the heat shield plate 100 may be obtained by providing aluminum vapor deposition, aluminum foil, etc., on the side of the plate facing the heat-generating element, i.e., the lower surface facing the drive unit 14.

[0055] According to the embodiment described above, the refrigerant circuit R dissipates heat to the coolant of the first coolant circuit C1 and absorbs heat to the coolants of the second and third coolant circuits C2 and C3, so the refrigerant circuit R can be concentrated in a relatively narrow area within the vehicle. Therefore, the refrigerant circuit R and the first to third heat exchangers 30, 40, and 50 can be isolated from the drive unit 14 by the heat shield plate 100. Since the heat shield plate 100 blocks radiant heat from the drive unit 14, the heating of the refrigerant circuit R due to that heat can be suppressed. In addition, if HC-based refrigerant leaks from the refrigerant circuit R, the heat shield plate 100 can prevent that refrigerant from flowing out into the drive unit 14.

[0056] Furthermore, according to the embodiment described above, the heat shield 100 is inclined downward toward one side (the right side in Figure 4), and the lower end 105 of the heat shield 100 is located outside the drive unit 14. HC-based refrigerants are generally heavier than air. Therefore, if an HC-based refrigerant leaks from the refrigerant circuit R, the upper surface of the heat shield 100 can catch the refrigerant and allow it to flow along the downward direction of the heat shield 100. The refrigerant can then be guided from the lower end 105 of the heat shield 100 to the outside of the drive unit 14.

[0057] Furthermore, according to the embodiment described above, since the heat shield plate 100 has an edge 110 that protrudes upward, it is possible to suppress the leakage of HC-based refrigerant from flowing down into the drive unit 14.

[0058] Furthermore, the lower end 105 of the heat shield 100 should be located on the side of the heat shield 100 where no other heat-generating elements or electrical equipment connectors or other wire connection points are located. That is, as shown in Figure 3, for example, if the power terminal 19 (wire connection point) of the auxiliary battery 18 is located on the left side of the vehicle (right side in Figure 3) of the heat shield 100, the lower end 105 of the heat shield 100 should be located on the right side of the vehicle (left side in Figure 3). This prevents leaked HC-based refrigerant from approaching the wire connection point (the power terminal 19 of the auxiliary battery 18 in the above example) or other heat-generating elements.

[0059] <Another heat shield> Figure 5 is a perspective view showing another heat shield 100a and its surrounding structure, with the outlet in the upper left of the figure indicating their schematic configuration. This heat shield 100a is constructed by adding an extension 104 to the heat shield 100 (see Figure 4). The extension 104 is a portion that extends the lower end 105 side (right side in Figure 5) of the heat shield 100a and is bent toward the drive unit 14 side. The heat shield 100a comprises a base 103 located below the refrigerant module RM and an extension 104 bent toward the base 103. The extension 104 has a shape that gradually tapers (becomes narrower) from top to bottom.

[0060] With this heat shield 100a, if HC-based refrigerant leaks from the refrigerant circuit R, the heat shield 100's base 103 can receive the refrigerant, which then flows to the extension 104, where it can be discharged to a limited area outside the drive unit 14.

[0061] Here, with reference to Figure 5, the arrangement of the heat shield 100a for a drive unit 14 having a high-temperature portion HTP and a low-temperature portion LTP will be described. The drive unit 14, which has an engine, is equipped with an intake manifold (not shown) and an exhaust manifold 190. The exhaust manifold 190 becomes hotter than the intake manifold. Therefore, the side of the drive unit 14 where the exhaust manifold 190 is located (left side in Figure 5) becomes the high-temperature portion HTP, and the side of the drive unit 14 where the intake manifold (not shown) is located (right side in Figure 5) becomes the low-temperature portion LTP, which is at a lower temperature than the high-temperature portion HTP. In this case, where the drive unit 14 (heat-generating element) includes a high-temperature portion HTP and a low-temperature portion LTP, as shown in Figure 5, it is preferable to make the portion of the heat shield 100a located above the high-temperature portion HTP (upper part 120U) higher than the portion of the heat shield 100a located above the low-temperature portion LTP (lower part 120L). This prevents the refrigerant circuit R from being heated by the high-temperature portion HTP of the drive unit 14. Furthermore, in the event that HC-based refrigerant leaks from the refrigerant circuit R, the refrigerant can be guided from the upper part 120U of the heat shield 100a, which can become hot, to the lower part 120L of the heat shield 100a, which can become colder.

[0062] The downward slope of the base 103 of the heat shield 100a may be curved, as shown inside the dashed line in the lower left of Figure 5. Inside the dashed line in Figure 5, a schematic cross-section of a heat shield 100a-1 having a base 103-1 that slopes downward in a curve is shown.

[0063] <Another heat shield> Figure 6 is a perspective view showing yet another heat shield 100b and its surrounding structure, with the outlet in the upper left of the figure indicating their general configuration. This heat shield 100b is constructed by making the base 103 of the heat shield 100a (see Figure 5) horizontal and providing extensions 104 on both the left and right sides. The two extensions 104 of the heat shield 100b each slope downward from top to bottom with a constant width. The left side 130L and the right side 130R of the heat shield 100b are the lower ends 105 of the heat shield 100, respectively, and the upwardly protruding edge 110 is omitted. The heat shield 100b has a symmetrical shape.

[0064] This heat shield 100b can also provide the same or similar effects as the heat shields 100, 100a, and 100a-1 described above.

[0065] <Partition plate for wire connection section> In the embodiments described above, the refrigerant module RM was positioned above the drive unit 14. However, as shown inside the dashed line in the lower left of Figure 4, the refrigerant module RM may also be positioned above the wire connection section 15. The wire connection section 15 is a connection point between a wire and electrical equipment, or between wires themselves. Examples of the wire connection section 15 include the power terminal of a battery, a connector for electrical equipment, a connector between wires, etc. Inside the dashed line in the lower left of Figure 4, the wire connection section 15 is shown, which is the connection point between the connector 302 of the wire 300 and the connector 202 of the electrical equipment 200 (inverter, etc.). A partition plate 101 is positioned between the refrigerant module RM and the wire connection section 15. This partition plate 101 may be a heat-insulating plate (heat shield) or a non-heat-insulating plate. In this specification, the term "partition plate" includes both heat-insulating plates (heat shields) and non-heat-insulating plates. The partition plate 101 of the wire connection section 15 may be any of the shapes and arrangements of the heat shield plates 100, 100a, 100a-1, and 100b described above.

[0066] <Variation> In the embodiments described above, the refrigerant module RM was positioned above the drive unit 14, but the refrigerant module RM may also be positioned below the drive unit 14. For example, the refrigerant module RM may be positioned behind the front end 14F (see Figure 3) of the drive unit 14 and below the drive unit 14. A heat shield is placed between the drive unit 14 and the refrigerant module RM.

[0067] Furthermore, the refrigerant module RM may be positioned adjacent to heat-generating elements other than the drive unit 14. In the vehicle 10, the refrigerant module RM and heat-generating elements such as the drive unit 14 may be arranged side by side in the vertical, longitudinal, or lateral directions. A heat shield is placed between the refrigerant module RM and the heat-generating elements such as the drive unit 14. The material of the heat shield may be, for example, metal or resin.

[0068] Furthermore, in the vehicle 10, the refrigerant module RM and the wire connection section may be arranged side by side in the vertical, front-to-back, or left-to-right direction. A partition plate is placed between the refrigerant module RM and the wire connection section. The partition plate may be made of, for example, metal or resin.

[0069] Furthermore, in the embodiments described above, the refrigerant circuit R was integrated by the plate 150 to constitute the refrigerant module RM. However, the refrigerant circuit R does not necessarily have to be integrated by the plate 150 or the like. That is, the multiple devices and refrigerant piping constituting the refrigerant circuit R only need to be located on one side of the heat shield (or partition plate). For example, the multiple devices constituting the refrigerant circuit R may be individually held in structures within the engine room 92.

[0070] <Another air conditioning unit> Next, another air conditioning system will be described. Figure 7 is a schematic diagram showing the configuration of another air conditioning system 12a. This air conditioning system 12a is configured by omitting the expansion valve 24b, the third heat exchanger 50, and the third coolant circuit C3 from the air conditioning system 12 described above (see Figure 1). The refrigerant circuit Ra of this air conditioning system 12a is configured by sequentially connecting the compressor 20, condenser 22, receiver 28, expansion valve 24a, and evaporator 26a with refrigerant piping.

[0071] This air conditioning unit 12a is configured not to cool the battery 54 (see Figure 1). The battery 54 may be cooled by a separate cooling device provided separately from the air conditioning unit 12a. Furthermore, vehicles such as engine-powered vehicles that do not have a battery 54 (a battery that supplies power to the motor) do not require a cooling device for the battery, and therefore this air conditioning unit 12a can be used.

[0072] In this air conditioning system 12a, the equipment (components) located inside the dashed line in Figure 7 are arranged on one side of the heat shield or partition plate. These equipment (components) may be arranged on one side of the heat shield or partition plate in the form of an integrated refrigerant module RMa, or individually held by structures within the vehicle body. [Explanation of Symbols]

[0073] 10 Vehicle, 12,12a Air conditioning system, 14 Drive unit (heat-generating element), 14F Front end, 15 Wiring connection section, 18 Auxiliary battery, 19 Power terminal, 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, 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, 80 Blower, 82 Air mix door, 90 Passenger compartment, 92 Engine room, 94 Dashboard, 96 Floor panel, 100, 100a, 100a-1, 100b Heat shield, 101 Partition plate, 103 Base, 104 Extension, 105 Bottom edge, 110 Edge, 120U Top, 120L Bottom, 130F Front edge, 130B Rear edge, 130L Left edge, 130R Right edge, 150 Plate, 152 Refrigerant piping, 190 Exhaust manifold, 200 Electrical equipment, 202 Connector, 300 Wire, 302 Connector, HTP High temperature section, LTP Low temperature section, R, Ra Refrigerant circuit, RM, RMa 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.

Claims

1. In-vehicle air conditioning system, A refrigerant circuit through which a hydrocarbon refrigerant circulates has a compressor, a condenser for heat dissipation, an expansion valve, and an evaporator for heat absorption, A first heat exchanger, which is integrated with the condenser of the refrigerant circuit and transfers heat from the refrigerant in the condenser to the first coolant, A first coolant circuit having a radiator through which the first coolant circulates, A second heat exchanger, which is integrated with the evaporator of the refrigerant circuit, cools the second coolant with the refrigerant in the evaporator, A second coolant circuit having a cooler core through which the second coolant circulates, The cooler core has an air passage located inside, and the air conditioning unit cools the air passing through the air passage and blows it into the passenger compartment. The system comprises a refrigerant circuit and the first and second heat exchangers, and a heat shield plate positioned between them and a heat-generating element located inside the vehicle. In-vehicle air conditioner.

2. An in-vehicle air conditioning system according to claim 1, The refrigerant circuit and the first and second heat exchangers are located above the heat-generating element. The heat shield is inclined downward toward one side. The lower end of the heat shield is located outside the heat-generating element. In-vehicle air conditioner.

3. An in-vehicle air conditioning system according to claim 2, The aforementioned heat-generating element includes a high-temperature portion and a low-temperature portion that is at a lower temperature. The heat shield plate includes an upper part located above the high-temperature portion of the heat-generating element, and a lower part located below the upper part and above the low-temperature portion of the heat-generating element. In-vehicle air conditioner.

4. An in-vehicle air conditioning system according to any one of claims 1 to 3, The refrigerant circuit and the first and second heat exchangers are located above the heat-generating element. The heat shield includes two opposing sides having an edge that protrudes upward, and at least one side located outside the heat-generating element and lacking the edge. In-vehicle air conditioner.

5. In-vehicle air conditioning system, A refrigerant circuit through which a hydrocarbon refrigerant circulates has a compressor, a condenser for heat dissipation, an expansion valve, and an evaporator for heat absorption, A first heat exchanger, which is integrated with the condenser of the refrigerant circuit and transfers heat from the refrigerant in the condenser to the first coolant, A first coolant circuit having a radiator through which the first coolant circulates, A second heat exchanger, which is integrated with the evaporator of the refrigerant circuit, cools the second coolant with the refrigerant in the evaporator, A second coolant circuit having a cooler core through which the second coolant circulates, The cooler core has an air passage located inside, and the air conditioning unit cools the air passing through the air passage and blows it into the passenger compartment. The system comprises a partition plate positioned between the refrigerant circuit and the first and second heat exchangers and the electrical wiring connection section located inside the vehicle. In-vehicle air conditioner.

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