Valve unit

Abstract

To provide a valve unit to be applied to a refrigeration cycle, capable of reducing energy loss.SOLUTION: A valve unit 1 includes: a first member 12 having a first flow path 141 constituting a high temperature passage connecting a compressor 102 to a radiator 104; a second member 14 having a second flow path 142 including an expansion part of an expansion device 2 and constituting a medium temperature passage connecting the radiator 104 to the expansion part; and a third flow path 143 constituting a low temperature passage connecting the expansion part to the vaporizer 106; and a third member 16 to which the first member 12 and the second member 14 are each fixed so that the first member 12 and the second member 14 are in no direct contact with each other.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a valve unit that is applied to a refrigeration cycle. [Background technology]

[0002] With the recent spread of electric vehicles, the development of their air conditioning systems is also progressing. Because electric vehicles do not have a heat source such as an internal combustion engine, they employ heat pump-type air conditioning systems that use a refrigerant for cycle operation for heating as well as cooling (see Patent Document 1).

[0003] Such vehicle heating and cooling systems have a refrigeration cycle including a compressor, an exterior heat exchanger, an expansion device, an evaporator, an interior heat exchanger, etc., and switch refrigerant circulation paths between heating and cooling operations. This means that multiple refrigerant circulation paths are formed, and a large number of control valves are required to control the flow of refrigerant. Therefore, it is important to be able to accommodate these control valves as compactly as possible within the limited space of the vehicle and to efficiently install each control valve on the vehicle body.

[0004] Therefore, a combined valve has been proposed in which multiple control valves are assembled into a unit in a common body. A single block-shaped body has multiple mounting holes to accommodate the valve parts of each control valve. This type of combined valve eliminates the need for piping to connect the control valves, and also reduces the number of joints connecting the piping, making the overall valve more compact than when each control valve is installed individually. Furthermore, since it is sufficient to fix the common body to the vehicle, the workload required to install the control valves into the vehicle is reduced. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Application Laid-Open No. 2012-20599 Summary of the Invention [Problem to be solved by the invention]

[0006] However, because such a combined valve is compact overall, the refrigerant passages of each control valve are close to each other. Therefore, if a passage through which a high-temperature refrigerant flows (also called a "high-temperature passage") and a passage through which a low-temperature refrigerant flows (also called a "low-temperature passage") are close to each other in the system, heat is transferred between the high-temperature refrigerant and the low-temperature refrigerant, resulting in energy loss. This may result in a decrease in the efficiency of the refrigeration cycle.

[0007] One object of the present invention is to reduce energy loss in a valve unit applied to a refrigeration cycle. [Means for solving the problem]

[0008] One aspect of the present invention is a valve unit applicable to a refrigeration cycle including a compressor, a radiator, an expansion device, and an evaporator. The valve unit includes a first member having a first flow path forming a high-temperature passage connecting the compressor and the radiator, a second member containing an expansion section of the expansion device and having a second flow path forming a medium-temperature passage connecting the radiator and the expansion section, and a third flow path forming a low-temperature passage connecting the expansion section and the evaporator, and a third member to which the first member and the second member are fixed so as not to come into direct contact with each other.

[0009] In this valve unit, the first flow path constitutes a high-temperature passage, so the first member is relatively hot. Meanwhile, the second flow path constitutes a medium-temperature passage, and the third flow path constitutes a low-temperature passage, so the second member is divided into a medium-temperature region and a low-temperature region by the expansion section. In this configuration, the first and second members are integrated via the third member without direct contact, so heat transfer between the first and third flow paths can be suppressed. As a result, unnecessary heat exchange between the high-temperature refrigerant and the low-temperature refrigerant in the valve unit can be suppressed, reducing energy loss in the refrigeration cycle. [Effects of the Invention]

[0010] According to the present invention, energy loss can be reduced in a valve unit applied to a refrigeration cycle. [Brief explanation of the drawings]

[0011] [Figure 1] 1 is a system configuration diagram of a vehicle air conditioning and heating device according to a first embodiment. [Figure 2] FIG. 2 is a diagram illustrating the operation of a heating and cooling device. [Figure 3] FIG. 2 is a diagram illustrating a configuration of a valve unit. [Figure 4] FIG. 2 is a diagram illustrating a configuration of a valve unit. [Figure 5] FIG. 2 is a diagram illustrating a configuration of a valve unit. [Figure 6] FIG. 2 is a diagram illustrating a configuration of a valve unit. [Figure 7] FIG. 2 is a diagram illustrating a configuration of a valve unit. [Figure 8] FIG. 2 is a diagram illustrating a configuration of a valve unit. [Figure 9] 10A and 10B are diagrams showing the effects according to the installation mode of the valve unit. [Figure 10] FIG. 6 is a system configuration diagram of a vehicle air conditioning and heating device according to a second embodiment. [Figure 11] FIG. 2 is a diagram illustrating a configuration of a valve unit. [Figure 12] FIG. 2 is a diagram illustrating a configuration of a valve unit. [Figure 13] FIG. 2 is a diagram illustrating a configuration of a valve unit. [Figure 14] FIG. 2 is a diagram illustrating a configuration of a valve unit. [Figure 15] FIG. 2 is a diagram illustrating a configuration of a valve unit. DETAILED DESCRIPTION OF THE INVENTION

[0012] Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. For convenience, the following description may refer to the positional relationship of each structure based on the illustrated state. In the following embodiments and their modifications, substantially identical components will be designated by the same reference numerals, and their description will be omitted where appropriate.

[0013] [First embodiment] FIG. 1 is a system configuration diagram of a vehicle air conditioning system according to a first embodiment. The air conditioning system 100 includes a refrigeration cycle (refrigerant circulation circuit) in which a compressor 102, a condenser 104, an evaporator 106, an accumulator 108, and the like are connected by piping. The air conditioning system 100 is configured as an air conditioning system that conditions the interior of a vehicle by utilizing the heat of a refrigerant such as HFO-1234yf as the refrigerant changes state as it circulates through the refrigeration cycle. The air conditioning system 100 also functions as a cooling device that appropriately cools devices such as a battery installed in the vehicle.

[0014] The compressor 102, condenser 104, and accumulator 108 are provided outside the vehicle cabin. Meanwhile, a duct 110 is provided inside the vehicle cabin to perform heat exchange with the air, and an evaporator 106 is disposed upstream of the duct 110 in the air flow direction. The evaporator 106 functions as a "first evaporator." A heater core 112 is disposed downstream of the evaporator 106 in the duct 110, and an air mix door 114 is rotatably provided immediately upstream of the heater core 112.

[0015] In this embodiment, a water-cooled condenser 116 is provided between the compressor 102 and the condenser 104 in the refrigeration cycle. The water-cooled condenser 116 and the heater core 112 constitute a coolant circulation circuit (not shown). This coolant circulation circuit supplies coolant heated by heat exchange in the water-cooled condenser 116 to the heater core 112, allowing the heater core 112 to function as a heater. The coolant may be, for example, an aqueous solution (cooling water) containing ethylene glycol, propylene glycol, or the like as a main component. Note that such coolant circulation circuits are well known, and therefore a detailed description thereof will be omitted.

[0016] The cooling and heating device 100 is operated by switching between multiple refrigerant circulation passages during cooling operation and heating operation. In the refrigeration cycle, a first refrigerant circulation passage through which the refrigerant circulates during cooling operation and a second refrigerant circulation passage through which the refrigerant circulates during heating operation are formed. A valve unit 1 is provided to switch between these refrigerant circulation passages. The valve unit 1 is constructed by assembling multiple blocks, each having passages that form the refrigerant circulation passages. Each block functions as the body of a control valve (described in detail below).

[0017] The outlet (discharge chamber) of the compressor 102 is connected to the inlet of the water-cooled condenser 116 via a first passage 121. The outlet of the water-cooled condenser 116 is connected to the inlet of the condenser 104 via a second passage 122. The outlet of the condenser 104 is connected to the inlet of the evaporator 106 via a third passage 123. The outlet of the evaporator 106 is connected to the inlet of the accumulator 108 via a fourth passage 124. The outlet of the accumulator 108 is connected to the inlet (suction chamber) of the compressor 102 via a fifth passage 125.

[0018] A branch point P1 is provided midway through the second passage 122, from which a sixth passage 126 branches off. The sixth passage 126 is connected to the inlet of the water heat exchanger 120. The outlet of the water heat exchanger 120 is connected via a seventh passage 127 to a junction point P2 provided midway through the fourth passage 124. A connection point P3 (corresponding to the "first connection point") is provided midway through the third passage 123, and a connection point P4 (corresponding to the "second connection point") is provided midway through the sixth passage 126. The connection point P3 and the connection point P4 are connected by a connection passage 130.

[0019] The first passage 121, the second passage 122, the third passage 123, the fourth passage 124, and the fifth passage 125 form a first refrigerant circulation passage (see FIG. 2(A)). The first passage 121, the second passage 122 (upstream of the branch point P1), the sixth passage 126, the seventh passage 127, the fourth passage 124 (downstream of the junction point), and the fifth passage 125 form a second refrigerant circulation passage (see FIG. 2(B)). Furthermore, the first passage 121, the second passage 122, the third passage 123 (upstream of the connection point P3), the connecting passage 130, the sixth passage 126 (downstream of the connection point P4), the seventh passage 127, the fourth passage 124 (downstream of the junction point P2), and the fifth passage 125 form a third refrigerant circulation passage for cooling devices such as a battery (see FIG. 2(A)).

[0020] A valve unit 1 is provided across the first to third refrigerant circulation passages. The valve unit 1 includes expansion valves 2, 4, on-off valves 6, 8, and a check valve 10, and is unitized by assembling a first block 12, a second block 14, a third block 16, and a fourth block 18 that form the bodies of the respective control valves.

[0021] The first block 12 corresponds to the "first member" and constitutes the body of the on-off valve 6. The first block 12 has a first flow path 141 that constitutes the second passage 122, a branch flow path 132 that constitutes the sixth passage 126, and a branch point P1 between these flow paths. A valve portion of the on-off valve 6 is disposed downstream of the branch point P1 in the first flow path 141.

[0022] The second block 14 corresponds to the "second member" and constitutes the body of the expansion valve 2. The expansion valve 2 is a motor-driven electric valve that functions as the "first expansion device." The second block 14 has a refrigerant passage that constitutes the third passage 123, and a valve portion of the expansion valve 2 (which functions as the "expansion portion") is provided midway through the refrigerant passage. A second flow path 142 is formed upstream of this valve portion, and a third flow path 143 is formed downstream of it.

[0023] The third block 16 corresponds to the "third member" and constitutes a body shared by the on-off valve 8 and the check valve 10. The third block 16 has a fourth flow path 144 that constitutes the third passage 123, a fifth flow path 145 that constitutes the sixth passage 126, and a connecting passage 130 that connects the fourth flow path 144 and the fifth flow path 145. That is, a connection point P3 is provided midway through the fourth flow path 144, and a connection point P4 is provided midway through the fifth flow path 145. The connecting passage 130 is formed as an internal passage of the third block 16 so as to connect these connection points P3 and P4.

[0024] A check valve 10 is provided upstream of the connection point P3 in the fourth flow path 144, and a valve portion of the on-off valve 8 is provided upstream of the connection point P4 in the fifth flow path 145. The check valve 10 prevents backflow of refrigerant in the fourth flow path 144. The fifth flow path 145 is opened or closed by opening or closing the on-off valve 8. In other words, the sixth passage 126 is opened or closed. In this embodiment, the on-off valve 8 is a solenoid-driven electromagnetic valve, but it may also be an electrically operated valve. The third block 16 is also provided with a PT sensor 20 that detects the temperature and pressure of the refrigerant flowing through the connecting passage 130.

[0025] The fourth block 18 corresponds to the "fourth member" and constitutes the body of the expansion valve 4. The expansion valve 4 is an electric valve that functions as a "second expansion device." The fourth block 18 has a refrigerant passage that constitutes the sixth passage 126, and a valve portion of the expansion valve 4 (which functions as an "expansion portion") is provided midway through the refrigerant passage. A sixth flow path 146 is formed upstream of this valve portion, and a seventh flow path 147 is formed downstream of it. The sixth flow path 146 connects the valve portion of the expansion valve 4 to the fifth flow path 145. The seventh flow path 147 constitutes a low-temperature passage that connects the valve portion of the expansion valve 4 to the water heat exchanger 120.

[0026] The first passage 121 and the second passage 122 correspond to a "high temperature passage" connecting the compressor 102 and the condenser 104. That is, the first flow path 141, which is a part of the second passage 122, constitutes the "high temperature passage." The second flow path 142 and its upstream side in the third passage 123 correspond to a "medium temperature passage" connecting the condenser 104 and the valve portion (expansion portion) of the expansion valve 2. That is, the second flow path 142 constitutes the "medium temperature passage." The third flow path 143 and its downstream side in the third passage 123 correspond to a "low temperature passage" connecting the valve portion (expansion portion) of the expansion valve 2 and the evaporator 106. That is, the third flow path 143 constitutes the "low temperature passage."

[0027] The first block 12 is fixed to one side of the third block 16, and the second block 14 and the fourth block 18 are fixed to the opposite side. The fourth flow path 144 communicates with the second flow path 142 at its downstream end. The fifth flow path 145 communicates with the branch flow path 132 at its upstream end and with the sixth flow path 146 at its downstream end.

[0028] The compressor 102 is configured as an electric compressor that houses a motor and a compression mechanism in a housing. The compressor 102 is driven by current supplied from a battery, and the refrigerant discharge capacity changes depending on the rotation speed of the motor. Note that the electric compressor itself is well known, so a description thereof will be omitted.

[0029] The condenser 104 functions as a "heat radiator" that radiates heat from the refrigerant passing through it during cooling operation. The condenser 104 exchanges heat between the outside air and the refrigerant.

[0030] The evaporator 106 functions as an interior evaporator that evaporates the refrigerant passing through it. The refrigerant, which has become low temperature and low pressure by passing through the expansion valve 2, evaporates as it passes through the evaporator 106. Air introduced from the upstream side of the duct 110 is cooled by its latent heat of evaporation. The cooled and dehumidified air is then divided into two parts, one that passes through the heater core 112 and one that bypasses the heater core 112, depending on the opening of the air mix door 114. The air passing through the heater core 112 is heated during its passage. The air that has passed through the heater core 112 and the air that has bypassed it are mixed downstream of the heater core 112, adjusted to a target temperature, and supplied to the vehicle interior through an air outlet (not shown).

[0031] The air conditioning system 100 configured as described above is controlled by a control unit 150. The control unit 150 calculates the control amount of each actuator to realize the room temperature set by the vehicle occupant, and outputs a control signal to the drive circuit of each actuator. The control unit 150 determines the control amount (open / close state) of each control valve and the drive amount of the compressor 102 based on information detected by various sensors, such as the temperature inside and outside the vehicle and the temperature of air blown out of the evaporator 106, and supplies a control current to drive them. As a result, the compressor 102 introduces refrigerant at a suction pressure Ps through its suction chamber, compresses it, and discharges it as refrigerant at a discharge pressure Pd.

[0032] Fig. 2 is a diagram showing the operation of the air conditioning and heating device 100. Fig. 2(A) shows cooling operation, and Fig. 2(B) shows heating operation. The thick lines and arrows in the diagram indicate the flow of refrigerant, and an "x" indicates that the flow of refrigerant is blocked.

[0033] (Cooling operation) 2(A), during cooling operation, in valve unit 1, expansion valves 2 and 4 and on-off valve 6 are opened, and on-off valve 8 is closed. As a result, the first refrigerant circulation passage and the third refrigerant circulation passage are opened, and the second refrigerant circulation passage is blocked. Therefore, high-temperature, high-pressure gas refrigerant discharged from compressor 102 is condensed by passing through water-cooled condenser 116 and condenser 104.

[0034] The refrigerant discharged from the condenser 104 is supplied to the expansion valve 2 on the one hand, and to the expansion valve 4 on the other hand. One of the refrigerants is throttled and expanded by the expansion valve 2, becoming a low-temperature, low-pressure atomized refrigerant which is introduced into the evaporator 106. The refrigerant evaporates as it passes through the evaporator 106, cooling the air inside the vehicle cabin. At this time, the air mix door 114 is closed or only slightly opened, so that appropriately cooled air is supplied into the vehicle interior. The refrigerant discharged from the evaporator 106 is separated into gas and liquid in the accumulator 108. The gas refrigerant after separation is returned to the compressor 102.

[0035] The other refrigerant is throttled and expanded by the expansion valve 4, becoming a low-temperature, low-pressure atomized refrigerant, which is introduced into the water heat exchanger 120. The refrigerant evaporates as it passes through the water heat exchanger 120, cooling devices such as the battery. The water heat exchanger 120 functions as a "second evaporator" located outside the vehicle cabin. The refrigerant discharged from the water heat exchanger 120 is separated into gas and liquid in the accumulator 108. The gas refrigerant after separation is returned to the compressor 102.

[0036] (Heating operation) 2(B), during heating operation, in the valve unit 1, the expansion valve 4 and the on-off valve 8 are opened, and the expansion valve 2 and the on-off valve 6 are closed. As a result, the second refrigerant circulation passage is opened, and the first refrigerant circulation passage and the third refrigerant circulation passage are blocked. As a result, the refrigerant does not pass through the condenser 104 and the evaporator 106, and these devices essentially do not function.

[0037] The refrigerant discharged from the compressor 102 is condensed by passing through the water-cooled condenser 116. The refrigerant is throttled and expanded by the expansion valve 4, becoming a low-temperature, low-pressure atomized refrigerant that is introduced into the water heat exchanger 120. The refrigerant evaporates as it passes through the water heat exchanger 120, cooling the battery. The refrigerant discharged from the water heat exchanger 120 is separated into gas and liquid in the accumulator 108. The gas refrigerant after separation is returned to the compressor 102.

[0038] At this time, the evaporator 106 does not function, so the air mix door 114 is opened wide to supply moderately heated air into the vehicle interior. Even during heating operation, the expansion valve 2 is opened during dehumidification to allow the evaporator 106 to function.

[0039] Next, a specific configuration of the valve unit 1 will be described. Figures 3 to 8 are diagrams showing the configuration of the valve unit 1. Figure 3 is a perspective view seen from above, Figure 4 is a front view, and Figure 5 is a plan view. Figure 6 is a cross-sectional view taken along the line AA in Figure 5, Figure 7 is a cross-sectional view taken along the line BB in Figure 5, and Figure 8 is a cross-sectional view taken along the line CC in Figure 5.

[0040] 3 to 5, the valve unit 1 is configured by assembling an on-off valve 6 on one side of a generally rectangular parallelepiped third block 16, and assembling expansion valves 2 and 4 on the opposite side. An on-off valve 8 and a PT sensor 20 are assembled in the third block 16, and a check valve 10 (see FIG. 1) is built in.

[0041] In this embodiment, the third block 16 is obtained by die-casting an aluminum alloy, but it may also be produced by forging or using a 3D printer. Alternatively, it may be produced by extrusion and cutting. Alternatively, the third block 16 may be obtained by processing (e.g., injection molding) a resin material that has a lower thermal conductivity than metal. The third block 16 forms a body 22 shared by the on-off valve 8 and the check valve 10. The body 22 contains the valve portions of the on-off valve 8 and the check valve 10. The on-off valve 8 is an electromagnetic valve that drives the valve portion with a solenoid 24. The solenoid 24 and the PT sensor 20 are mounted on the top surface of the third block 16.

[0042] The on-off valve 6 is constructed by assembling a body 30 containing a valve portion and a solenoid 32 that drives the valve portion to open and close, one above the other. The body 30 is made of a first block 12 and is fixed to the left side surface of a third block 16 with fixing members (screws, etc.). In this embodiment, the body 30 is obtained by die-casting an aluminum alloy, but it may also be produced by a 3D printer. Alternatively, it may be produced by extrusion and cutting.

[0043] The expansion valve 2 is configured by assembling a body 34 and a motor unit 36 ​​one above the other. The body 34 is configured from the second block 14 and is fixed to the right side surface of the third block 16 with fixing members (screws, etc.). In this embodiment, the body 34 is obtained by die-casting an aluminum alloy, but it may also be produced by a 3D printer. Alternatively, it may be produced by extrusion and cutting.

[0044] The expansion valve 4 is constructed by assembling a body 38 and a motor unit 40 one above the other. The body 38 is constructed from the fourth block 18 and is fixed to the right side of the third block 16 with fixing members (screws, etc.). The expansion valve 4 is disposed side by side with the expansion valve 2 (see Figures 3 and 5). In this embodiment, the body 38 is obtained by die-casting an aluminum alloy, but it may also be produced by a 3D printer. Alternatively, it may be produced by extrusion and cutting.

[0045] 6, the on-off valve 6 is a so-called pilot-operated normally-open solenoid valve. An inlet port 50 for introducing refrigerant flowing from the compressor 102 side (water-cooled condenser 116 side) and an outlet port 52 for discharging the refrigerant to the condenser 104 side are provided on the left side surface of the body 30. A first flow path 141 is provided to connect the inlet port 50 and the outlet port 52. The on-off valve 6 opens and closes the first flow path 141 by driving a solenoid 32. The specific configuration of the on-off valve 6 can be, for example, the structure described in JP 2023-128388 A, but detailed description thereof will be omitted.

[0046] An outlet port 54 that forms one end of a branch flow path 132 is provided on the right side surface of the body 30. The other end of the branch flow path 132 is connected midway through the first flow path 141 (upstream of the valve portion of the on-off valve 6).

[0047] The on-off valve 8 is also a pilot-operated normally-open solenoid valve. An inlet port 56 is provided on the upper left side surface of the body 22 so as to communicate with an outlet port 54 of the body 30. A seal ring 55 (O-ring) is interposed between the body 22 and the body 30 so as to surround the connection between the outlet port 54 and the inlet port 56.

[0048] An outlet port 58 for discharging the refrigerant is provided in the lower right side surface of the body 22. A fifth flow path 145 is provided in the body 22 to connect the inlet port 56 and the outlet port 58. A valve portion of an on-off valve 8 is provided midway through the fifth flow path 145. The on-off valve 8 opens and closes the fifth flow path 145 when driven by a solenoid 24. The specific configuration of the on-off valve 8 can be, for example, that described in Japanese Patent Application Laid-Open No. 2013-245769, but detailed description thereof will be omitted.

[0049] The body 22 is provided with a connection point P4 with the connection passage 130 on the downstream side of the valve portion of the fifth flow path 145. The connection point P4 is located on the upstream side of the outlet port 58.

[0050] The expansion valve 4 is an electrically operated valve configured by assembling a motor unit 40 on the upper surface of a body 38. The motor unit 40 includes a rotor unit and a stator unit. A valve portion is provided at the tip of the rotor unit. The body 38 contains the valve portion of the expansion valve 4. The specific configuration of the expansion valve 4 can be, for example, the structure described in JP 2023-53708 A, but detailed description thereof will be omitted.

[0051] An inlet port 60 is provided at the top of the left side surface of the body 38, and an outlet port 62 is provided in the center of the right side surface. A valve portion of the expansion valve 4 is provided midway through a refrigerant passage that connects the inlet port 60 and the outlet port 62. A sixth flow path 146 forms an upstream passage of the valve portion, and a seventh flow path 147 forms a downstream passage of the valve portion. The body 38 is assembled to the body 22 so that the outlet port 58 and the inlet port 60 communicate with each other. A seal ring 59 (O-ring) is interposed between the body 22 and the body 38 so as to surround the connection portion between the outlet port 58 and the inlet port 60.

[0052] 7, an inlet port 64 is provided on the front surface of the body 22 to introduce refrigerant flowing from the condenser 104 side. The inlet port 64 has a stepped circular hole shape and is coaxially connected to the connecting passage 130. The connecting passage 130 is provided with a connection point P3 on the side closer to the inlet port 64 and a connection point P4 on the side farther from the inlet port 64.

[0053] A check valve 10 is disposed inside the inlet port 64 in the body 22. The check valve 10 includes a stepped cylindrical valve body 70 and a valve element 72 that is coaxially supported inside the valve body 70. The valve body 70 is configured by assembling, in the axial direction, a bearing member 74 that supports the valve element 72 so that it can be displaced in the axial direction, and a valve seat forming member 76 that has a valve seat 82 at one end. A seal ring 78 (O-ring) is provided on the outer periphery of the valve seat forming member 76, ensuring sealing between it and the inner circumferential surface of the body 22.

[0054] The valve element 72 is a stepped cylinder with a seal ring 80 (O-ring) fitted to its large-diameter tip, forming a detachable portion (seal portion) with the valve seat. A spring 77 is interposed between the valve element 72 and the bearing member 74, which urges the valve element 72 in the valve closing direction from the downstream side. The valve element 72 opens and closes by being attached to and detached from the valve seat 82 from the downstream side. The PT sensor 20 detects the temperature and pressure of the refrigerant flowing through the connecting passage 130 downstream of the check valve 10.

[0055] As shown in FIG. 8, a discharge port 66 for discharging the refrigerant is also provided on the lower right side surface of the body 22. The discharge port 66 forms one end of the fourth flow path 144. The expansion valve 2 is an electric valve configured by assembling a motor unit 36 ​​on the upper surface of the body 34. The motor unit 36 ​​includes a rotor unit and a stator unit. A valve portion is provided at the tip of the rotor unit. The body 34 contains the valve portion of the expansion valve 2. The specific configuration of the expansion valve 2 can be, for example, the structure described in JP 2023-53708 A, but detailed description thereof will be omitted.

[0056] An inlet port 67 is provided at the top of the left side surface of the body 34, and an outlet port 68 is provided at the center of the right side surface. A valve portion of the expansion valve 2 is provided midway through a refrigerant passage that connects the inlet port 67 and the outlet port 68. A second flow path 142 forms an upstream passage of the valve portion, and a third flow path 143 forms a downstream passage of the valve portion. The body 34 is assembled to the body 22 so that the outlet port 66 and the inlet port 67 communicate with each other. A seal ring 69 (O-ring) is interposed between the body 22 and the body 34 so as to surround the connection portion between the outlet port 66 and the inlet port 67.

[0057] Figure 9 is a diagram showing the effects based on the configuration of the valve unit 1. Figure 9(A) shows an example of an installation mode (installation orientation) of the valve unit 1 in the embodiment. Figure 9(B) is a cross-sectional view taken along arrow DD in Figure 9(A). The outline arrow in the figure indicates the downward direction in the direction of gravity.

[0058] 9(A), the expansion valve 2 is positioned relatively higher, and the expansion valve 4, the on-off valve 6, and the on-off valve 8 are positioned relatively lower. Accordingly, as shown in FIG. 9(B), with respect to the connection passage 130 connecting the fourth flow path 144 and the fifth flow path 145, the connection point P4 (second connection point) is positioned lower than the connection point P3 (first connection point). It goes without saying that the installation manner of the valve unit 1 is not limited to that shown in the figure.

[0059] In this configuration, the temperature rises in the lower region of the body 22, that is, around the valve portion of the on-off valve 8 that communicates with the high-temperature passage (see FIG. 1). Therefore, when the on-off valve 8 is in a closed state as shown in the figure and refrigerant stagnation occurs in the region 145a immediately downstream of the valve portion, it is expected that part of the refrigerant will vaporize in the stagnation, causing bubbles to form.

[0060] In this regard, in the present embodiment, the connection point P4 is closer to the valve portion of the on-off valve 8 than the connection point P3. That is, the expansion valve 4 is connected to a flow path closer to the valve portion of the on-off valve 8 than the expansion valve 2. Therefore, bubbles generated in the stagnation region are easily guided from the connection point P4, which is closer to the stagnation region, to the expansion valve 4 side through the fifth passage 145. In other words, the bubbles are less likely to be guided to the connection point P3, which is far from the stagnation region, and are prevented from being guided to the expansion valve 2 side through the fourth passage 144. If bubbles are guided to the expansion valve in a slightly open state, they will generate abnormal noise (the sound of the refrigerant passing through the valve portion). However, according to the present embodiment, even if the abnormal noise occurs, it can be biased toward the expansion valve 4 side (outside the vehicle cabin). That is, the generation of abnormal noise at the expansion valve 2 (inside the vehicle cabin) can be prevented or suppressed, thereby preventing or suppressing discomfort to the vehicle driver.

[0061] As described above, in this embodiment, the expansion valves 2, 4, on-off valves 6, 8, and check valve 10 are assembled into their respective bodies to form a unit, eliminating the need for piping and fittings to connect the individual control valves, and allowing for a compact configuration of the valve unit 1. Because multiple control valves are integrated into the valve unit 1, when mounting the unit to the vehicle body via a bracket, the valve unit 1 can be secured to a single bracket, and the bracket can then be secured to the vehicle body. There is no need to prepare a bracket for each control valve, which also reduces the workload required for installation into the vehicle.

[0062] On the other hand, by adopting such a configuration, the high-temperature passage and the low-temperature passage in the refrigeration cycle are close to each other in the valve unit 1, but by disposing a third member, which serves as a medium-temperature section, between them, the heat conduction can be suppressed. That is, by interposing the third block 16 between the body 30 (first block 12) of the on-off valve 6, which forms part of the high-temperature passage, and the bodies 34, 38 (second block 14, fourth block 18) of the expansion valves 2, 4, which form part of the low-temperature passage, the high-temperature passage and the low-temperature passage can be physically separated. This suppresses heat conduction from the high-temperature passage to the low-temperature passage, and reduces energy loss in the refrigeration cycle.

[0063] In particular, to maintain cooling performance during cooling operation, it is necessary to supply low-temperature refrigerant to the evaporator 106 (see FIG. 2(A)), and the second block 14 and fourth block 18, which are at low temperatures, can be reliably separated from the first block 12, which is at high temperatures, by interposing the third block 16. Meanwhile, the third block 16 is at a medium temperature because the refrigerant, whose temperature has been reduced to a certain extent after passing through the condenser 104, passes through it. Therefore, the temperature of the third block 16 has little effect on the low-temperature refrigerant, making it easy to maintain cooling performance during cooling operation.

[0064] 4, the first block 12 abuts against the left side surface (first side surface) of the third block 16, and the second block 14 abuts against the right side surface (second side surface) of the third block 16. In other words, the second block 14, which has a relatively low temperature, and the first block 12, which has a relatively high temperature, are located on opposite sides of the third block 16, thereby effectively suppressing heat conduction.

[0065] 8, the left side surface (third side surface) of the second block 14 abuts against the right side surface of the third block 16, and the second flow path 142 opens at this abutting surface. Meanwhile, the third flow path 143 opens at the right side surface (fourth side surface) of the second block 14. That is, by opening the third flow path 143 on the side of the second block 14 opposite to the second flow path 142, the low-temperature passage, of which the third flow path 143 is a part, can be further separated from the high-temperature passage.

[0066] In this configuration, by having only the upper part of the second block 14 abut against the third block 16, that is, by making the abutting surface with the third block 16 on the left side of the second block 14 smaller than the non-abutting surface, it is possible to further suppress heat conduction from the high-temperature passage to the low-temperature passage via the third block 16. As shown in the figure, a space below the third block 16 is formed between the first block 12 and the second block 14, and this space below also functions as a heat insulating space.

[0067] Furthermore, in the second block 14, the second flow path 142 and the third flow path 143 are offset in the height direction with the valve portion of the expansion valve 2 as the boundary, and the third flow path 143 is formed at a position displaced in the height direction from the contact surface between the second block 14 and the third block 16. In other words, the displacement of the third flow path 143, which constitutes the low-temperature passage, in the height direction from the contact surface (heat transfer surface) further contributes to suppressing heat conduction.

[0068] The above-described relationship between the second block 14 and the third block 16 also applies to the relationship between the fourth block 18 and the third block 16. That is, as shown in Fig. 6, the left side surface of the fourth block 18 abuts against the right side surface of the third block 16, and the sixth flow path 146 opens at the abutting surface. Meanwhile, the seventh flow path 147 opens at the right side surface of the fourth block 18. That is, by opening the seventh flow path 147 on the side of the fourth block 18 opposite to the sixth flow path 146, the low-temperature passage, of which the seventh flow path 147 is a part, can be further separated from the high-temperature passage.

[0069] In this configuration, by having only the upper part of the fourth block 18 abut against the third block 16, that is, by making the abutting surface with the third block 16 on the left side of the fourth block 18 smaller than the non-abutting surface, it is possible to further suppress heat conduction from the high-temperature passage to the low-temperature passage via the third block 16. A space below the third block 16 is formed between the first block 12 and the fourth block 18, and this space below also functions as a heat insulating space.

[0070] Furthermore, in the fourth block 18, the sixth flow path 146 and the seventh flow path 147 are offset in the height direction with the valve portion of the expansion valve 2 as the boundary, and the seventh flow path 147 is formed at a position displaced in the height direction from the contact surface between the fourth block 18 and the third block 16. In other words, the displacement of the seventh flow path 147, which constitutes the low-temperature passage, in the height direction from the contact surface (heat transfer surface) further contributes to suppressing heat conduction.

[0071] [Second embodiment] FIG. 10 is a system configuration diagram of a vehicle air conditioning system according to the second embodiment. The cooling and heating device 200 of this embodiment differs from the first embodiment in the arrangement of the expansion valves 2 and 4 in the valve unit 201. The following description will focus on the differences from the first embodiment.

[0072] In the valve unit 201, the first block 12 and the second block 14 are fixed to one side of the third block 16, and the fourth block 18 is fixed to the opposite side. In other words, it is the same as the first embodiment except that the on-off valve 6 and the expansion valve 2 are assembled to the same side of the third block 16. The operation of the air conditioning and heating device 200 is also the same as that of the air conditioning and heating device 100 of the first embodiment, and therefore a description thereof will be omitted.

[0073] Figures 11 to 15 are diagrams showing the configuration of valve unit 201. Figure 11 is a perspective view seen from above, and Figure 12 is a plan view. Figure 13 is a cross-sectional view taken along the line EE in Figure 12, Figure 14 is a cross-sectional view taken along the line FF in Figure 12, and Figure 15 is a cross-sectional view taken along the line GG in Figure 12.

[0074] 11 to 14, the valve unit 201 is configured by assembling the on-off valve 6 and the expansion valve 2 on the left side of the third block 16, and assembling the expansion valve 4 on the opposite side. The third block 16 is assembled with the on-off valve 8 and the PT sensor 20, and has a built-in check valve 10 (see FIG. 10).

[0075] 12 and 14, the expansion valve 4 is fixed to the third block 16 at a position offset from the on-off valve 8 in the longitudinal direction. Therefore, the overall length of the immediately downstream region 245a of the valve portion of the on-off valve 8 is longer than the immediately downstream region 145a in the first embodiment. Therefore, the connection passage 130 is short, and the distance between the connection point P3 and the connection point P4 is also short. Note that the fourth flow path 144 shown in FIG. 14 is located on the front side of the figure, but is shown to show its positional relationship with the fifth flow path 145 (see the two-dot chain line).

[0076] As shown in Figure 15, expansion valve 2 and expansion valve 4 are located on opposite sides of the third block 16, but the fourth flow path 144 is located closer to the front than the fifth flow path 145, i.e., closer to the inlet port 64 (see Figure 14).

[0077] With this configuration, similar to the first embodiment, the fifth flow path 145 is closer to the valve portion of the on-off valve 8 than the fourth flow path 144. Therefore, even if the immediate downstream region 245a stagnates and air bubbles are generated when the on-off valve 8 is in a closed state, the air bubbles can be easily guided toward the fifth flow path 145. In other words, even if abnormal noise is generated by the air bubbles, the air bubbles can be biased toward the expansion valve 4 side (outside the vehicle cabin). In other words, similar to the first embodiment, the generation of abnormal noise at the expansion valve 2 (inside the vehicle cabin) can be prevented or suppressed, and discomfort to the driver of the vehicle can be prevented or suppressed.

[0078] 12, in the valve unit 201, the body 30 (first block 12) of the on-off valve 6, in which part of the high-temperature passage is formed, and the body 34 (second block 14) of the expansion valve 2, in which part of the low-temperature passage is formed, are fixed to the left side surface (first side surface) of the body 22. In this respect, the heat conduction suppression effect may be reduced compared to the first embodiment.

[0079] However, as in the first embodiment, the third block 16 is interposed between the first block 12 and the second block 14, suppressing heat conduction from the high-temperature passage to the low-temperature passage. Also, as shown in FIG. 15 , only the upper portion of the second block 14 abuts against the third block 16. That is, the abutting surface of the right side of the second block 14 with the third block 16 is smaller than the non-abutting surface. Furthermore, in the second block 14, the second flow path 142 and the third flow path 143 are offset in the height direction with the valve portion of the expansion valve 2 as the boundary, and the third flow path 143 is formed at a position offset in the height direction from the abutting surface between the second block 14 and the third block 16. These points are similar to those in the first embodiment. As a result, energy loss in the refrigeration cycle can be reduced.

[0080] Although the preferred embodiment of the present invention has been described above, it goes without saying that the present invention is not limited to this specific embodiment, and various modifications are possible within the scope of the technical concept of the present invention.

[0081] [Variations] In the above embodiment, the body 30 of the on-off valve 6 is the first block 12, the body 34 of the expansion valve 2 is the second block 14, the body 22 shared by the on-off valve 8 and the check valve 10 is the third block 16, and the body 38 of the expansion valve 4 is the fourth block 18. That is, an example has been shown in which the first member having the first flow path 141, the second member having the second flow path 142 and the third flow path 143, the third member having the fourth flow path 144 and the fifth flow path 145, and the fourth member having the sixth flow path 146 and the seventh flow path 147 are each configured as a block. In a modified example, at least one of the first to fourth members may be configured as a structure other than a block, for example, a piping structure (piping-like structure) obtained by die casting, a 3D printer, injection molding, or the like.

[0082] In the above embodiment, as shown in Fig. 8, a configuration has been exemplified in which the left side surface (third side surface) of the second block 14 abuts against the right side surface of the third block 16, and the third flow path 143 opens on the right side surface of the second block 14. That is, an example has been shown in which the side surface (fourth side surface) on which the third flow path 143 opens is the side of the second block 14 opposite the third side surface. In a modified example, the fourth side surface on which the third flow path 143 opens may be the bottom surface of the second block 14. The fourth side surface may be any side surface of the second block 14 (second member) that is different from the third side surface.

[0083] In the above embodiment, an example of a plurality of control valves constituting the valve unit is shown, but it goes without saying that the specific configuration of the control valves constituting the valve unit, such as the type, number, shape, size, etc., can be set as appropriate. For example, the valve unit may be constituted by assembling control valves other than motor-operated valves and solenoid valves, such as control valves having a drive unit that senses the pressure of the refrigerant and operates autonomously.

[0084] In the above embodiment, electric expansion valves (expansion valves 2 and 4) are used as the expansion device. However, a thermostatic expansion valve that detects the temperature and pressure at the outlet side of the downstream heat exchanger and autonomously opens and closes the valve section can also be used. Alternatively, an orifice having a contraction section (expansion section) with a constant passage diameter can be used as the expansion device. A solenoid-driven expansion valve (see, for example, JP 2023-108658 A) can also be used.

[0085] In the above embodiment, a structure in which the valve unit 1 includes multiple expansion valves has been exemplified. However, if cooling of the battery by a refrigeration cycle (supply of low-temperature refrigerant to the water heat exchanger 120) is not required, the expansion valve 4 may be omitted. In this case, the fourth block 18 is unnecessary. The fifth flow path 145 and the on-off valve 8 are also unnecessary. As a result, the connection passage 130 and the check valve 10 are also unnecessary. The third block 16 (third member) is sufficient as long as it has the fourth flow path 144 that constitutes the medium-temperature passage. Even when such a configuration is adopted, the presence of the third block 16 can suppress heat conduction from the first flow path 141 to the third flow path 143, i.e., heat conduction from the high-temperature passage to the low-temperature passage, and the same effects as those of the above embodiment can be obtained.

[0086] The present invention is not limited to the above-described embodiments and modifications, and the components can be modified without departing from the spirit of the invention. Various inventions can be formed by appropriately combining multiple components disclosed in the above-described embodiments and modifications. Furthermore, some components can be omitted from all the components shown in the above-described embodiments and modifications. [Explanation of symbols]

[0087] 1 valve unit, 2 expansion valve, 4 expansion valve, 6 on-off valve, 8 on-off valve, 10 check valve, 12 first block, 14 second block, 16 third block, 18 fourth block, 22 body, 24 solenoid, 30 body, 32 solenoid, 34 body, 36 motor unit, 38 body, 40 motor unit, 70 valve body, 72 valve body, 82 valve seat, 100 heating and cooling device, 102 compressor, 104 condenser, 106 evaporator, 108 accumulator, 112 heater core, 116 water-cooled condenser, 120 water heat exchanger, 121 first passage, 122 second passage, 123 third passage, 124 fourth passage, 125 fifth passage, 126 sixth passage, 127 seventh passage, 130 connecting passage, 132 Branch flow path, 141 first flow path, 142 second flow path, 143 third flow path, 144 fourth flow path, 145 fifth flow path, 146 sixth flow path, 147 seventh flow path, 150 control unit, 200 heating and cooling device, 201 valve unit.

Claims

1. A valve unit applied to a refrigeration cycle provided with a compressor, a radiator, an expansion device, and an evaporator, a first member having a first flow path that constitutes a high-temperature passage connecting the compressor and the radiator; a second member containing an expansion portion of the expansion device and including a second flow path constituting a medium-temperature passage connecting the radiator and the expansion portion, and a third flow path constituting a low-temperature passage connecting the expansion portion and the evaporator; a third member to which the first member and the second member are fixed so that the first member and the second member do not come into direct contact with each other; A valve unit comprising:

2. the third member has a fourth flow path that constitutes the medium temperature passage, The valve unit according to claim 1 , wherein the fourth flow path and the second flow path communicate with each other.

3. the second member has a third side surface that abuts against the third member and a fourth side surface that is different from the third side surface, the second flow path opens to a surface of the third side surface that abuts against the third member, while the third flow path opens to the fourth side surface; The valve unit according to claim 2, wherein a contact surface of the third side surface with the third member is smaller than a non-contact surface of the third side surface with the third member.

4. the expansion device is an expansion valve; the second flow path and the third flow path communicate with each other via a valve portion of the expansion valve, 4. The valve unit according to claim 2, wherein the third flow path is formed at a position offset in a height direction from a contact surface between the second member and the third member.

5. the refrigeration cycle includes a first evaporator disposed inside the vehicle compartment as the evaporator, and a second evaporator disposed outside the vehicle compartment; the third member has a fifth flow path that communicates with a branch flow path that branches off from the first flow path in the first member, a first expansion device as the expansion device; a fourth member including an expansion portion of a second expansion device separate from the first expansion device, and including a sixth flow passage connecting the fifth flow passage and the expansion portion of the second expansion device, and a seventh flow passage constituting a low-temperature passage connecting the expansion portion of the second expansion device and the second evaporator; Furthermore, 3. The valve unit according to claim 2, wherein an on-off valve that opens or closes the fifth flow path is attached to the third member.

6. the third member has a connecting passage that connects a first connecting point provided in the middle of the fourth flow path and a second connecting point provided in the middle of the fifth flow path, The valve unit according to claim 5, wherein the on-off valve is provided upstream of the second connection point in the fifth flow path.

7. 7. The valve unit according to claim 6, wherein the second expansion device is connected to a flow path closer to the valve portion of the on-off valve than the first expansion device.

8. the third member has a first side surface that contacts the first member and a second side surface that contacts the second member, the first member and the second member are fixed to a first side surface of the third member, 7. The valve unit according to claim 5, wherein the fourth member is fixed to a second side surface of the third member, the second side surface being opposite to the first side surface.

9. the third member has a first side surface that contacts the first member and a second side surface that contacts the second member, The valve unit according to claim 2, wherein the second side surface is a surface of the third member opposite to the first side surface.

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