Heat exchanger

Abstract

A header (21) of an outdoor heat exchanger (1) is formed with a branch flow path (57) that causes refrigerant to flow from one end portion (41) side to the other end portion (42) side, an inflow space (43) that is adjacent to the one end portion (41) side of the branch flow path (57), an inflow port (61) that causes refrigerant to flow from the inflow space (43) into the one end portion (41) side of the branch flow path (57), and a plurality of insertion spaces (46) that are arranged in a header length direction (25) and in which one ends of a plurality of heat transfer tubes (23) are respectively arranged. The plurality of insertion spaces (46) include a first one end portion side insertion space (91) that is adjacent to the inflow space (43), and a second one end portion side insertion space (92) that is adjacent to the first one end portion side insertion space (91). The header (21) is formed with an one end portion side communication flow path (106) that communicates the first one end portion side insertion space (91) and the second one end portion side insertion space (92).

Description

Technical Field

[0001] The technology disclosed herein relates to heat exchangers. Background Technology

[0002] A heat exchanger with a manifold is known, which splits a gas-liquid two-phase refrigerant into multiple heat transfer tubes (Patent Document 1). Inside the manifold, multiple insertion spaces at one end of each heat transfer tube are connected to a circulation path. The circulation path includes a first flow path, a second flow path, a first reversing flow path connecting the upper end of the first flow path to the upper end of the second flow path, and a second reversing flow path connecting the lower end of the second flow path to the lower end of the first flow path. The gas-liquid two-phase refrigerant flowing into the manifold circulates within the circulation path as follows: it rises in the first flow path, flows from the upper end of the first flow path to the upper end of the second flow path via the first reversing flow path, and then falls in the second flow path, flowing from the lower end of the second flow path to the lower end of the first flow path via the second reversing flow path. This heat exchanger prevents refrigerant from stagnating in the upper part of the first flow path by circulating the gas-liquid two-phase refrigerant flowing into the manifold within the circulation path. It also allows the gas-liquid two-phase refrigerant to be appropriately distributed to multiple heat transfer tubes so that the flow rates of the refrigerant flowing to each heat transfer tube are equal.

[0003] Patent Document 1: Japanese Patent Application Publication No. 2019-056544 Summary of the Invention

[0004] However, this type of heat exchanger has the following problems: When the flow rate of the gas-liquid two-phase refrigerant in the circulation path is small, the liquid refrigerant may not be able to rise in the first flow path, resulting in a decrease in the proportion of liquid refrigerant flowing into the upper heat transfer tubes among the multiple heat transfer tubes. Additionally, in this type of heat exchanger, when the flow rate of the gas-liquid two-phase refrigerant in the circulation path is large, the liquid refrigerant may stagnate at the top of the first flow path, resulting in an increase in the proportion of liquid refrigerant flowing into the uppermost heat transfer tubes among the multiple heat transfer tubes. When the amount of liquid refrigerant flowing into the multiple heat transfer tubes is uneven, even if the heat exchanger still has the capacity to evaporate all the liquid refrigerant in the gas-liquid two-phase refrigerant, in heat transfer tubes with less liquid refrigerant flowing in, the complete evaporation of the liquid refrigerant increases the superheat of the refrigerant, while in heat transfer tubes with more liquid refrigerant flowing in, the liquid refrigerant cannot be completely evaporated, leading to a decrease in the heat exchanger's heat transfer performance.

[0005] The disclosed technology was developed in view of the above-mentioned problems, and its purpose is to provide a heat exchanger for improving the heat exchange performance of gas-liquid two-phase refrigerants.

[0006] A heat exchanger according to one embodiment of the present disclosure comprises: a plurality of heat transfer tubes; and a manifold for joining the plurality of heat transfer tubes, the manifold being formed with: a flow path for allowing refrigerant to flow from one end side to another end side in the longitudinal direction of the manifold; an inflow space adjacent to one end side of the flow path in the longitudinal direction of the manifold for allowing refrigerant to flow into the flow path; an inlet for allowing refrigerant to flow from the inflow space into one end side of the flow path in the longitudinal direction of the manifold; and a plurality of insertion spaces arranged in the longitudinal direction of the manifold for allowing the heat transfer tubes to flow into the flow path. Multiple heat transfer tubes are respectively configured at one end, and the multiple insertion spaces include: a first end-side insertion space adjacent to the inflow space; a second end-side insertion space adjacent to the first end-side insertion space; a first other end-side insertion space located closest to the other end; a second other end-side insertion space adjacent to the first other end-side insertion space; and multiple intermediate-side insertion spaces, which are different from the first end-side insertion space, the second end-side insertion space, the first other end-side insertion space, and the second other end-side insertion space. The manifold forms at least one of an end-side connecting flow path and a other end-side connecting flow path. The first end-side connecting flow path connects the first end-side insertion space with the second end-side insertion space, and the other end-side connecting flow path connects the first other end-side insertion space with the second other end-side insertion space. The manifold also forms a plurality of middle-side inlet holes, which connect the plurality of middle-side insertion spaces to the branch flow path respectively. When the first end-side connecting flow path is formed, the manifold also forms the first end-side inlet hole and the second end-side inlet hole. At least one of the first end-side inlet hole connects the inflow space to the first end-side insertion space, and the second end-side inlet hole connects the branch flow path to the second end-side insertion space. When the other end-side connecting flow path is formed, the manifold also forms at least one of the first other end-side inlet hole and the second other end-side inlet hole. The first other end-side inlet hole connects the branch flow path to the first other end-side insertion space, and the second other end-side inlet hole connects the branch flow path to the second other end-side insertion space.

[0007] The disclosed heat exchanger can improve the heat exchange performance of gas-liquid two-phase refrigerant. Attached Figure Description

[0008] Figure 1 This is a refrigerant circuit diagram of an air conditioner equipped with the heat exchanger of Embodiment 1.

[0009] Figure 2 This is a front view of the heat exchanger in Example 1.

[0010] Figure 3 This is a top view showing the heat exchanger of Embodiment 1.

[0011] Figure 4 This is a cross-sectional view of the heat transfer tube of the heat exchanger in Example 1.

[0012] Figure 5 This is an exploded perspective view showing the internal structure of the expansion valve side manifold of the heat exchanger in Embodiment 1.

[0013] Figure 6 This is a schematic longitudinal cross-sectional view of the expansion valve side manifold of the heat exchanger in Example 1.

[0014] Figure 7 This is a schematic longitudinal cross-sectional view of the expansion valve side manifold of the heat exchanger in Example 2.

[0015] Figure 8 This is a cross-sectional view showing the flow of low-pressure gas-liquid two-phase refrigerant (especially liquid refrigerant) into the insertion space at the first end of the heat exchanger in Example 2.

[0016] Figure 9 This is a cross-sectional view showing the flow of low-pressure gas-liquid two-phase refrigerant (especially liquid refrigerant) into the insertion space at the first other end of the heat exchanger in Example 2.

[0017] Figure 10 This is a schematic longitudinal cross-sectional view of the expansion valve side manifold of the heat exchanger in Example 3.

[0018] Figure 11 This is a cross-sectional view showing the flow of low-pressure gas-liquid two-phase refrigerant (especially liquid refrigerant) into the insertion space at the second end of the heat exchanger in Example 3.

[0019] Figure 12 This is a cross-sectional view showing the flow of low-pressure gas-liquid two-phase refrigerant (especially liquid refrigerant) into the insertion space at the second other end of the heat exchanger in Example 3.

[0020] Figure 13 This is a cross-sectional view showing the first end side insertion space and the second end side insertion space of the heat exchanger in Embodiment 4.

[0021] Figure 14 This is a cross-sectional view showing the insertion space at the first other end and the insertion space at the second other end of the heat exchanger in Embodiment 4.

[0022] Figure 15 This is a side view of the expansion valve side manifold of the heat exchanger in Embodiment 5. Detailed Implementation

[0023] The heat exchanger according to the embodiments disclosed in this application will now be described in detail with reference to the accompanying drawings. However, the technology disclosed herein is not limited to the following description. Furthermore, in the following description, the same structural elements are labeled with the same symbols, and repeated descriptions are omitted.

[0024] Example 1

[0025] like Figure 1 As shown, the heat exchanger in Embodiment 1 is the outdoor heat exchanger 1 installed in the air conditioner 10. Figure 1 This is a refrigerant circuit diagram for an air conditioner 10 equipped with an outdoor heat exchanger 1 as described in Embodiment 1. The air conditioner 10 includes an outdoor unit 2 and an indoor unit 3. The outdoor unit 2 is located outdoors. The indoor unit 3 is located inside a room.

[0026] Air conditioner 10 includes a refrigerant circuit 4. The refrigerant circuit 4 includes a compressor 5, a four-way valve 6, an indoor heat exchanger 7, an expansion valve 8, and an outdoor heat exchanger 1. The compressor 5 is located inside the outdoor unit 2. A suction pipe 11 and a discharge pipe 12 are connected to the compressor 5. The compressor 5 compresses the refrigerant supplied by the suction pipe 11 and discharges the refrigerant at a flow rate corresponding to the compressor speed to the discharge pipe 12. The higher the compressor speed, the greater the flow rate of refrigerant discharged by the compressor 5 to the discharge pipe 12 per unit time.

[0027] A four-way valve 6 is located inside the outdoor unit 2. The four-way valve 6 connects to the suction pipe 11 and the discharge pipe 12, is connected to the outdoor heat exchanger 1 via refrigerant piping 14, and is connected to the indoor heat exchanger 7 via refrigerant piping 15. The four-way valve 6 switches the refrigerant circuit 4 between heating and cooling cycles. When the refrigerant circuit 4 is switched to heating cycle, the discharge pipe 12 is connected to the indoor heat exchanger 7 via the four-way valve 6, and the suction pipe 11 is connected to the outdoor heat exchanger 1 via the four-way valve 6. When the refrigerant circuit 4 is switched to cooling cycle, the discharge pipe 12 is connected to the outdoor heat exchanger 1 via the four-way valve 6, and the suction pipe 11 is connected to the indoor heat exchanger 7 via the four-way valve 6.

[0028] An indoor heat exchanger 7 is located inside the indoor unit 3. One refrigerant inlet / outlet of the indoor heat exchanger 7 is connected to the expansion valve 8 via refrigerant piping 16, and the other refrigerant inlet / outlet is connected to the four-way valve 6 via refrigerant piping 15 as described above. The indoor unit 3 causes air from the room in which the indoor unit 3 is located to flow through the indoor heat exchanger 7 by rotating a fan (not shown), exchanging heat with the refrigerant, and then blowing the air after heat exchange into the room. The expansion valve 8 is located inside the outdoor unit 2. The expansion valve 8 is connected to the outdoor heat exchanger 1 via refrigerant piping 17. The air conditioner 10 adjusts the amount of refrigerant flowing through the indoor heat exchanger 7 according to the required air conditioning capacity of the indoor unit 3 by adjusting the opening of the expansion valve 8.

[0029] Outdoor unit 2 includes an outdoor fan 18. The outdoor fan 18 is located inside outdoor unit 2. The outdoor fan 18 blows outdoor air to the ventilation space 19 inside outdoor unit 2. When outdoor unit 2 is properly installed, the outdoor fan 18 directs the airflow in a roughly horizontal direction 20. An outdoor heat exchanger 1 is located inside and fixed to outdoor unit 2, allowing air flowing through the ventilation space 19 to pass through the outdoor heat exchanger 1. The outdoor heat exchanger 1 facilitates heat exchange between the refrigerant flowing through it and the air flowing through the ventilation space 19.

[0030] Figure 2 This is a front view showing the outdoor heat exchanger 1 of Embodiment 1. The outdoor heat exchanger 1 includes an expansion valve side manifold 21 (manifold), a compressor side manifold 22, multiple heat transfer tubes 23, and multiple fins 24. The expansion valve side manifold 21 is formed in a cylindrical shape, and is configured such that the extension direction of the expansion valve side manifold 21, i.e., the manifold length direction 25 (length direction), is perpendicular to the bottom surface of the outdoor unit 2 (not shown), and the expansion valve side manifold 21 is fixed to the outdoor unit 2. A refrigerant piping 17 is connected to the expansion valve side manifold 21, and the expansion valve 8 is connected to the expansion valve side manifold 21 via the refrigerant piping 17.

[0031] The compressor-side manifold 22 is cylindrical, configured such that its extension direction is parallel to the length direction 25, and it is fixed to the outdoor unit 2. A flow distribution space is formed inside the compressor-side manifold 22. The refrigerant piping 14 is connected to the compressor-side manifold 22 so that the four-way valve 6 is connected to the flow distribution space via the refrigerant piping 14.

[0032] like Figure 2 and Figure 3 As shown, multiple heat transfer tubes 23 are configured such that their extension direction (i.e., the length direction 26) is orthogonal to the length direction 25 of the manifold, and they are arranged at equal intervals along the length direction 25 of the manifold. One end of each heat transfer tube 23 is connected to the expansion valve side manifold 21. The other end of each heat transfer tube 23 is connected to the compressor side manifold 22. By connecting both ends of the multiple heat transfer tubes 23 to the expansion valve side manifold 21 and the compressor side manifold 22 respectively, the multiple heat transfer tubes 23 are fixed to the expansion valve side manifold 21 and the compressor side manifold 22, and the outdoor heat exchanger 1 is fixed to the outdoor unit 2 through the expansion valve side manifold 21 and the compressor side manifold 22.

[0033] Multiple fins 24 are formed into flat plates. Figure 3 This is a top view showing the outdoor heat exchanger 1 of Embodiment 1. Multiple fins 24 are configured perpendicular to the length direction 26 of the heat transfer tubes (parallel to the ventilation direction 20) and are arranged at equal intervals along the length direction 26 of the heat transfer tubes. The multiple fins 24 are fixed to multiple heat transfer tubes 23 for thermal connection.

[0034] like Figure 4As shown, each of the multiple heat transfer tubes 23 is formed in a flat shape. Figure 4 This is a cross-sectional view of the heat transfer tube 23 of the outdoor heat exchanger 1 in Embodiment 1. Multiple flow paths 33 are formed inside the heat transfer tube 23, arranged in the ventilation direction 20. By connecting the other ends of the multiple heat transfer tubes 23 to the compressor-side manifold 22, the multiple flow paths 33 are connected to the distribution space of the compressor-side manifold 22.

[0035] Figure 5 This is an exploded perspective view showing the internal structure of the expansion valve side manifold 21 of the outdoor heat exchanger 1 in Embodiment 1. The expansion valve side manifold 21 includes multiple plate-shaped components 71-76, all of which are rectangular in shape. The multiple plate-shaped components 71-76 are stacked and joined together, with the stacking direction generally parallel to the length direction 26 of the heat transfer tube. The multiple plate-shaped components 71-76 include a refrigerant piping side plate-shaped component 71, a heat transfer tube side plate-shaped component 72, multiple circulating flow path plate-shaped components 73, multiple reversing flow path plate-shaped components 74, multiple insertion space plate-shaped components 75, and an inlet plate-shaped component 76. Figure 5 As shown, the plate-shaped components are stacked from upstream to downstream in the inlet direction 48 (the direction in which the refrigerant flows in the outdoor heat exchanger 1 when it functions as an evaporator), in the following order: refrigerant piping side plate-shaped component 71, multiple reversible flow path plate-shaped components 74, multiple circulating flow path plate-shaped components 73, inlet hole plate-shaped component 76, multiple insertion space plate-shaped components 75, and heat transfer tube side plate-shaped component 72. Furthermore, in the following description, when referring to components formed by joining multiple plate-shaped components 71 to 76, the term "multiple" may be omitted.

[0036] Each circulating flow path is formed with plate-shaped components 73 having the same shape as each other (in this embodiment 1, Figure 5 The three circulating flow path plate-shaped components 73 shown are of the same shape. A reversing flow path plate-shaped component 74 is disposed between the circulating flow path plate-shaped component 73 and the refrigerant piping side plate-shaped component 71. Each insertion space plate-shaped component 75 is formed to be the same shape as the others (in this embodiment 1, ...). Figure 5 The three plate-shaped members 75 for inserting spaces shown are of the same shape. The plate-shaped member 75 for inserting spaces is disposed between the plate-shaped member 76 for inlet holes and the plate-shaped member 72 for the heat transfer tube side. The plate-shaped member 76 for inlet holes is disposed between the plate-shaped member 73 for the circulation path and the plate-shaped member 75 for inserting spaces.

[0037] Furthermore, in the following description, the end face of the lower end of the expansion valve side manifold 21 along the length direction 25 is referred to as one end 41, and the end face of the opposite side of the upper end of the expansion valve side manifold 21 is referred to as the other end 42.

[0038] The expansion valve side manifold 21 is formed by stacking the plate-shaped components described above from upstream to downstream in the inlet direction 48 in the following order: refrigerant piping side plate-shaped component 71, reversible flow path plate-shaped component 74, circulating flow path plate-shaped component 73, inlet hole plate-shaped component 76, insertion space plate-shaped component 75, and heat transfer tube side plate-shaped component 72. This creates an inflow space 43, a refrigerant piping through hole 44, a circulating flow path 45 (branch flow path), an inlet 61, multiple insertion spaces 46, multiple heat transfer tube through holes 47, and multiple inlet holes 62 inside the expansion valve side manifold 21. The inflow space 43 is located in the region inside the expansion valve side manifold 21 near one end 41. The inflow space 43 is formed by inflow space holes 83 formed on each circulating flow path plate-shaped component 73.

[0039] The refrigerant piping through-hole 44 is formed by a refrigerant piping hole 77 formed on the refrigerant piping side plate-like component 71 and a refrigerant piping hole 78 formed on the reversible flow path plate-like component 74. Therefore, the refrigerant piping through-hole 44 is positioned upstream of the inflow space 43 in the inlet direction 48. The refrigerant piping 17 passes through the refrigerant piping through-hole 44, and the inflow space 43 is connected to the expansion valve 8 via the refrigerant piping 17.

[0040] The circulation path 45 is formed by a circulation path plate-shaped member 73 and a reversal path plate-shaped member 74, and includes a first flow path 57, a second flow path 58, a first reversal flow path 51, and a second reversal flow path 52. The first flow path 57 is formed by first flow path holes 84 formed on a plurality of circulation path plate-shaped members 73. The second flow path 58 is formed by second flow path holes 85 formed on a plurality of circulation path plate-shaped members 73. Therefore, the first flow path 57 and the second flow path 58 are arranged with the inflow space 43 in the manifold length direction 25 and are positioned above the inflow space 43. The first flow path 57 is formed along a straight line parallel to the manifold length direction 25. The second flow path 58 is positioned on the windward side of the first flow path 57 in the ventilation direction 20 and is formed along another straight line parallel to the manifold length direction 25.

[0041] The first reversible flow path 51 is formed by first reversible flow path holes 81 formed on a plurality of reversible flow path plate-like members 74, causing the refrigerant flowing through the first flow path 57 to be reversed to the second flow path 58. That is, the direction of refrigerant flow through the first reversible flow path 51 is perpendicular to the inlet direction 48 and parallel to the ventilation direction 20. The second reversible flow path 52 is formed by second reversible flow path holes 82 formed on a plurality of reversible flow path plate-like members 74, causing the refrigerant flowing through the second flow path 58 to be reversed to the first flow path 57. That is, the direction of refrigerant flow through the second reversible flow path 52 is perpendicular to the inlet direction 48 and parallel to the ventilation direction 20. Therefore, the first reversible flow path 51 and the second reversible flow path 52 are arranged in the manifold length direction 25 and are positioned upstream of the first flow path 57 and the second flow path 58 in the inlet direction 48. The first reversing flow path 51 is formed in the region near the other end 42 and is connected to the upper end of the first flow path 57 and the upper end of the second flow path 58. The second reversing flow path 52 is formed in the lower region near one end 41 and is connected to the lower end of the first flow path 57 and the lower end of the second flow path 58.

[0042] The inlet 61 is formed by inlet holes 86 formed on a plurality of circulating flow path plate members 73. Therefore, the inlet 61 is disposed between the inflow space 43 and the first flow path 57, and the refrigerant flowing into the inlet 61 flows to the first flow path 57 via the inlet 61.

[0043] Multiple insertion spaces 46 are connected by multiple insertion space holes 87 formed on multiple insertion space plate members 75. Therefore, when viewed from the area where the inflow space 43 and the circulation path 45 are configured, the multiple insertion spaces 46 are arranged downstream of the inlet direction 48 and along the manifold length direction 25. The multiple insertion spaces 46 have approximately equal volumes.

[0044] Multiple inlet holes 62 are formed in the inlet hole plate-shaped component 76. Therefore, the multiple inlet holes 62 are arranged in the manifold length direction 25 and are respectively disposed between the first flow path 57 and the multiple insertion spaces 46.

[0045] Multiple heat transfer tube through holes 47 are formed in the heat transfer tube side plate-like component 72. Therefore, when viewed from the multiple insertion spaces 46, the multiple heat transfer tube through holes 47 are arranged downstream of the introduction direction 48 and are equally spaced along the length direction 25 of the manifold. The multiple insertion spaces 46 are respectively connected to each heat transfer tube 23 via the multiple heat transfer tube through holes 47.

[0046] A solder filler metal is applied to the surface of each of the multiple plate-shaped components 71-76. By stacking the plate-shaped components and heating them in a furnace, the solder filler metal melts and joins them together, thereby forming the expansion valve side manifold 21. In this way, the expansion valve side manifold 21 is formed by stacking multiple plate-shaped components 71-76 with their outer peripheries aligned. Therefore, for example, compared to a manifold formed by combining plate-shaped components with U-shaped components to create a box shape, the expansion valve side manifold 21 can improve strength and durability. Furthermore, since the expansion valve side manifold 21 is formed by stacking multiple plate-shaped components 71-76, changes to the refrigerant flow path in the expansion valve side manifold 21 or the number of heat transfer tubes 23 to be joined can be accommodated simply by changing some of the plate-shaped components. Therefore, the design freedom of the outdoor heat exchanger 1, including the expansion valve side manifold 21, can be increased, and development and manufacturing costs can be reduced.

[0047] Multiple heat transfer tubes 23 pass through multiple heat transfer tube through holes 47 and are connected to the expansion valve side manifold 21.

[0048] Figure 6 This is a schematic longitudinal cross-sectional view of the expansion valve side manifold 21. The plurality of insertion spaces 46 include: a first end-side insertion space 91, a second end-side insertion space 92, a first other end-side insertion space 93, a second other end-side insertion space 94, and a plurality of intermediate-side insertion spaces 95. The first end-side insertion space 91 is the insertion space located on the side closest to the first end 41 among the plurality of insertion spaces 46, and is located downstream of the inlet space 43 in the inlet direction 48. The second end-side insertion space 92 is the insertion space adjacent to the first end-side insertion space 91 among the plurality of insertion spaces 46 and located on the upper side of the manifold length direction 25. That is, the second end-side insertion space 92 is located downstream of the inlet direction 48 of the lower end region 96 on the lower side of the manifold length direction 25 in the first flow path 57. The lower end region 96 is the region upstream of the inlet direction 48 of the second end-side insertion space 92 in the first flow path 57. The first other end side insertion space 93 is the insertion space located closest to the other end 42 among the plurality of insertion spaces 46. That is, the first other end side insertion space 93 is located downstream of the inlet direction 48 of the upper region 97 below the manifold length direction 25 in the first flow path 57. The second other end side insertion space 94 is located downstream of the inlet direction 48 of the upper region 97, and is the insertion space adjacent to the first other end side insertion space 93 and located below the manifold length direction 25 among the plurality of insertion spaces 46. The upper region 97 is the region upstream of the inlet direction 48 of the first other end side insertion space 93 and the second other end side insertion space 94 in the first flow path 57.

[0049] The plurality of inlet holes 62 include: a first end-side inlet hole 101, a second end-side inlet hole 102, a first other end-side inlet hole 103, a second other end-side inlet hole 104, and a plurality of middle-side inlet holes 105. The first end-side inlet hole 101 is the inlet hole located on the side closest to the first end 41 among the plurality of inlet holes 62, used to connect the inflow space 43 with the first end-side insertion space 91. The first end-side insertion space 91 is connected to the inflow space 43 via the first end-side inlet hole 101. The second end-side inlet hole 102 is the inlet hole adjacent to the first end-side inlet hole 101 and located on the upper side of the manifold length direction 25 among the plurality of inlet holes 62, used to connect the lower end region 96 of the first flow path 57 with the second end-side insertion space 92. The second end-side insertion space 92 is connected to the lower end region 96 of the first flow path 57 via the second end-side inlet hole 102. The first other end side inlet hole 103 is the inlet hole 62 located closest to the other end 42, used to connect the upper end region 97 of the first flow path 57 with the first other end side insertion space 93. The first other end side insertion space 93 is connected to the upper end region 97 of the first flow path 57 via the first other end side inlet hole 103. The second other end side inlet hole 104 is the inlet hole 62 adjacent to the first other end side inlet hole 103 and located on the lower side of the manifold length direction 25, used to connect the upper end region 97 of the first flow path 57 with the second other end side insertion space 94. The second other end side insertion space 94 is connected to the upper end region 97 of the first flow path 57 via the second other end side inlet hole 104. The plurality of middle-side inlet holes 105 are inlet holes 62 that are different from the first end-side inlet hole 101, the second end-side inlet hole 102, the first other end-side inlet hole 103, and the second other end-side inlet hole 104. They are formed between the second end-side inlet hole 102 and the second other end-side inlet hole 104 and are used to connect the first flow path 57 with the plurality of middle-side insertion spaces 95. The plurality of middle-side insertion spaces 95 are respectively connected to the first flow path 57 through the plurality of middle-side inlet holes 105.

[0050] An end-side connecting flow path 106 and another end-side connecting flow path 107 are also formed in the expansion valve side manifold 21. The end-side connecting flow path 106 connects the first end-side insertion space 91 and the second end-side insertion space 92, and is formed in the partition portion 108 that separates the first end-side insertion space 91 and the second end-side insertion space 92. The second end-side insertion space 92 is connected to the first end-side insertion space 91 via the end-side connecting flow path 106. The other end-side connecting flow path 107 connects the first other end-side insertion space 93 and the second other end-side insertion space 94, and is formed in the partition portion 109 that separates the first other end-side insertion space 93 and the second other end-side insertion space 94. The second other end-side insertion space 94 is connected to the first other end-side insertion space 93 via the other end-side connecting flow path 107. That is, some of the multiple insertion space plate-shaped members 75 also form a notch for an end-side connecting flow path and a notch for another end-side connecting flow path, which respectively form an end-side connecting flow path 106 and another end-side connecting flow path 107 when the multiple plate-shaped members 71 to 76 are stacked.

[0051] Air conditioner 10 can perform heating and cooling operations as described below.

[0052] Heating operation

[0053] Heating operation is performed, for example, when the air conditioner 10 is operated by the user to perform heating operation. When the air conditioner 10 is in heating operation, the four-way valve 6 switches the refrigerant circuit 4 to the heating cycle. The compressor 5 compresses the low-pressure gaseous refrigerant flowing from the four-way valve 6 into the suction pipe 11. The low-pressure gaseous refrigerant is compressed by the compressor 5 into a high-pressure gaseous refrigerant. The compressor 5 discharges the high-pressure gaseous refrigerant to the discharge pipe 12. Since the refrigerant circuit 4 is switched to the heating cycle, the high-pressure gaseous refrigerant discharged to the discharge pipe 12 flows into the indoor heat exchanger 7 via the four-way valve 6.

[0054] Indoor unit 3 allows air from the room containing indoor unit 3 to flow through indoor heat exchanger 7. Indoor heat exchanger 7 allows the high-pressure vapor refrigerant flowing into it to exchange heat with the air flowing through it, cooling the high-pressure vapor refrigerant and heating the air. Indoor unit 3 then blows the heated air out of indoor heat exchanger 7 into the room containing it, providing heating. The high-pressure vapor refrigerant is cooled and condensed in indoor heat exchanger 7, becoming a subcooled high-pressure liquid refrigerant. In other words, when air conditioner 10 is operating in heating mode, indoor heat exchanger 7 functions as a condenser. High-pressure liquid refrigerant flows out of indoor heat exchanger 7 and into expansion valve 8.

[0055] Expansion valve 8 reduces the pressure of the high-pressure liquid refrigerant flowing into it. The high-pressure liquid refrigerant is reduced by expansion valve 8 to become a low-pressure gas-liquid two-phase refrigerant. The low-pressure gas-liquid two-phase refrigerant flows out of expansion valve 8 and into refrigerant piping 17. Outdoor fan 18 directs outdoor air into ventilation space 19.

[0056] Low-pressure gas-liquid two-phase refrigerant flowing into refrigerant piping 17 flows into the inflow space 43 of expansion valve-side manifold 21 through refrigerant piping through hole 44. The low-pressure gas-liquid two-phase refrigerant flowing into inflow space 43 flows into the lower end region 96 of one end 41 of the first flow path 57 through inlet 61. The low-pressure gas-liquid two-phase refrigerant flowing into the lower end region 96 through inlet 61 becomes a jet flowing towards the other end 42, rising along the first flow path 57. After rising along the first flow path 57, the low-pressure gas-liquid two-phase refrigerant reaches the upper end region 97 of the other end 42 of the first flow path 57, and then flows into the second flow path 58 through the first reversal flow path 51. The low-pressure gas-liquid two-phase refrigerant flowing into the second flow path 58 through the first reversal flow path 51 descends along the second flow path 58.

[0057] The low-pressure gas-liquid two-phase refrigerant, after descending along the second flow path 58, flows into the lower region 96 of the first flow path 57 via the second reversal flow path 52. The low-pressure gas-liquid two-phase refrigerant flowing into the lower region 96 via the second reversal flow path 52 is pushed upwards by the jet of low-pressure gas-liquid two-phase refrigerant flowing into the lower region 96 via the inlet 61, and together with the low-pressure gas-liquid two-phase refrigerant flowing into the lower region 96 via the inlet 61, rises along the first flow path 57. That is, during heating operation, the low-pressure gas-liquid two-phase refrigerant flowing into the circulation flow path 45 circulates within the circulation flow path 45.

[0058] The low-pressure gas-liquid two-phase refrigerant flowing into the inflow space 43 further flows into the first end-side insertion space 91 through the first end-side inlet hole 101. The low-pressure gas-liquid two-phase refrigerant rising along the first flow path 57 flows into multiple insertion spaces 46, each different from the first end-side inlet hole 101, through multiple inlet holes 62. That is, the low-pressure gas-liquid two-phase refrigerant flowing in the lower region 96 of the first flow path 57 flows into the second end-side insertion space 92 through the second end-side inlet hole 102. The low-pressure gas-liquid two-phase refrigerant rising along the first flow path 57 flows into multiple intermediate insertion spaces 95 through multiple middle-side inlet holes 105. The low-pressure gas-liquid two-phase refrigerant flowing in the upper region 97 of the first flow path 57 flows into the second other end side insertion space 94 through the second other end side inlet hole 104, and flows into the first other end side insertion space 93 through the first other end side inlet hole 103.

[0059] Low-pressure gas-liquid two-phase refrigerant flows into multiple insertion spaces 46 and into multiple heat transfer tubes 23, flowing through multiple flow paths 33 formed inside the multiple heat transfer tubes 23. The low-pressure gas-liquid two-phase refrigerant flowing into the multiple heat transfer tubes 23 exchanges heat with the air flowing in the ventilation space 19, is heated and evaporates, becoming low-pressure gas-phase refrigerant, which flows out from the multiple heat transfer tubes 23. That is to say, when the air conditioner 10 is in heating mode, the outdoor heat exchanger 1 functions as an evaporator.

[0060] The low-pressure gaseous refrigerant flowing from multiple heat transfer pipes 23 converges at the compressor-side manifold 22 and flows out from the compressor-side manifold 22. The low-pressure gaseous refrigerant flowing out from the compressor-side manifold 22 flows into the four-way valve 6 via the refrigerant piping 14. Since the refrigerant circuit 4 is switched to the heating cycle, it flows into the suction pipe 11 of the compressor 5 via the four-way valve 6.

[0061] Regardless of the amount of refrigerant circulating in the refrigerant circuit 4, all refrigerant flows into the inflow space 43, thus causing liquid refrigerant to stagnate. When liquid refrigerant stagnates in the inflow space 43, the flow rate of liquid refrigerant in the low-pressure gas-liquid two-phase refrigerant flowing into the first end-side insertion space 91 via the first end-side inlet 101 is sometimes greater than the flow rate of liquid refrigerant flowing into the multiple middle-side insertion spaces 95. Because the outdoor heat exchanger 1 has an end-side connecting flow path 106, a portion of the flow rate of liquid refrigerant flowing into the first end-side insertion space 91 can flow out through the end-side connecting flow path 106 to the second end-side insertion space 92. Therefore, the outdoor heat exchanger 1 can make the flow rate of liquid refrigerant flowing from the first end side insertion space 91 into the plurality of heat transfer tubes 23 close to the flow rate of liquid refrigerant flowing into other heat transfer tubes, and can suppress the deviating flow of refrigerant to the plurality of heat transfer tubes 23.

[0062] When the low-pressure gas-liquid two-phase refrigerant rises along the first flow path 57, the gaseous refrigerant in the low-pressure gas-liquid two-phase refrigerant rises in the central part of the first flow path 57, while the liquid refrigerant in the low-pressure gas-liquid two-phase refrigerant is pushed against the inner wall of the first flow path 57 by the gaseous refrigerant rising in the central part of the first flow path 57. For example, when the cross-section of the first flow path 57 is quadrilateral, the liquid refrigerant is pushed to the four corners of the first flow path 57. When there is a high circulation rate with a large amount of refrigerant circulating in the refrigerant circuit 4, the liquid refrigerant pushed to the four corners of the first flow path 57 is pushed by the gaseous refrigerant rising in the central part of the first flow path 57 and rises along the inner wall of the first flow path 57. Because the liquid refrigerant rises along the inner wall of the first flow path 57, it is not easy for it to flow into the multiple insertion spaces 46 through the multiple inlet holes 62, and sometimes it will stagnate in the upper region 97 of the first flow path 57. When liquid refrigerant is retained in the upper region 97 of the first flow path 57, the flow rate of liquid refrigerant in the low-pressure gas-liquid two-phase refrigerant flowing into the first other-end-side insertion space 93 via the first other-end-side inlet 103 is sometimes greater than the flow rate of liquid refrigerant flowing from the first flow path 57 into the plurality of middle-end insertion spaces 95. The outdoor heat exchanger 1, by forming the other-end-side connecting flow path 107, allows a portion of the liquid refrigerant flowing into the first other-end-side insertion space 93 to flow out through the other-end-side connecting flow path 107 to the second other-end-side insertion space 94. Therefore, the outdoor heat exchanger 1 can make the flow rate of liquid refrigerant flowing in the heat transfer tubes inserted into the first other-end-side insertion space 93 in the plurality of heat transfer tubes 23 close to the flow rate of liquid refrigerant flowing into other heat transfer tubes, and can suppress the deflection of refrigerant flowing into the plurality of heat transfer tubes 23.

[0063] Refrigeration operation

[0064] When the user operates the air conditioner 10 to run in cooling mode, the four-way valve 6 is switched so that the refrigerant circuit 4 is in cooling cycle mode. The compressor 5 compresses the low-pressure gaseous refrigerant drawn in from the four-way valve 6 through the suction pipe 11. The low-pressure gaseous refrigerant is compressed by the compressor 5 into high-pressure gaseous refrigerant and discharged to the discharge pipe 12. Because the refrigerant circuit 4 is switched to cooling cycle mode, the high-pressure gaseous refrigerant discharged to the discharge pipe 12 flows into the outdoor heat exchanger 1 through the four-way valve 6 and the refrigerant piping 14.

[0065] The high-pressure gaseous refrigerant flowing into the outdoor heat exchanger 1 flows into the compressor-side manifold 22 and is distributed to multiple heat transfer tubes 23. The high-pressure gaseous refrigerant distributed to the multiple heat transfer tubes 23 condenses through heat exchange with the air flowing through the ventilation space 19 via the rotation of the outdoor fan 18, thus becoming a subcooled high-pressure liquid refrigerant. In other words, when the air conditioner 10 is in cooling operation, the outdoor heat exchanger 1 functions as a condenser. The high-pressure liquid refrigerant flows out from the multiple heat transfer tubes 23 and into multiple insertion spaces 46 of the expansion valve-side manifold 21. The high-pressure liquid refrigerant flowing into the insertion spaces 46 that are different from the first end-side insertion space 91 flows through multiple inlet holes 62 into the first flow path 57 of the circulation flow path 45 and converges. The high-pressure liquid refrigerant converging in the first flow path 57 flows into the inlet space 43 through the inlet 61. The high-pressure liquid refrigerant flowing into the first end side insertion space 91 flows into the inflow space 43 through the first end side inlet hole 101, and merges with the high-pressure liquid refrigerant flowing into the inflow space 43 through the inlet 61. The high-pressure liquid refrigerant flowing in the inflow space 43 flows into the refrigerant pipe 17 through the refrigerant pipe through hole 44, and flows into the expansion valve 8 through the refrigerant pipe 17.

[0066] The refrigerant oil contained in the high-pressure liquid refrigerant flowing in the first flow path 57 descends due to gravity and thus remains in the lower region 96 of the first flow path 57. The refrigerant oil remaining in the lower region 96 of the first flow path 57, together with the high-pressure liquid refrigerant, flows into the inflow space 43 through the inlet 61. The refrigerant oil remaining in the inflow space 43, together with the high-pressure liquid refrigerant, flows out from the outdoor heat exchanger 1 through the refrigerant piping 17. Therefore, when the outdoor heat exchanger 1 functions as a condenser, the outdoor heat exchanger 1 allows the refrigerant oil contained in the high-pressure liquid refrigerant to flow out from the outdoor heat exchanger 1 through the refrigerant piping 17, preventing the refrigerant oil from remaining in the outdoor heat exchanger 1.

[0067] The high-pressure liquid refrigerant flowing into expansion valve 8 is depressurized and becomes a low-pressure gas-liquid two-phase refrigerant, which flows out of expansion valve 8, through refrigerant piping 16, and into indoor heat exchanger 7. The rotation of an indoor fan (not shown) causes the low-pressure gas-liquid two-phase refrigerant flowing into indoor heat exchanger 7 to exchange heat with the room air drawn into indoor unit 3. Thus, the air flowing through indoor heat exchanger 7 is cooled using the low-pressure gas-liquid two-phase refrigerant, and the room is cooled by blowing the cooled air into the room where indoor unit 3 is located. On the other hand, the low-pressure gas-liquid two-phase refrigerant flowing into indoor heat exchanger 7 is heated and evaporated, becoming a low-pressure gas-phase refrigerant. In other words, when air conditioner 10 is operating in cooling mode, indoor heat exchanger 7 functions as an evaporator. The low-pressure gas-phase refrigerant flowing out of indoor heat exchanger 7 flows sequentially to refrigerant piping 15, four-way valve 6, and suction pipe 11, and is drawn into compressor 5 for further compression.

[0068] Effect of the heat exchanger in Example 1

[0069] The heat exchanger of Embodiment 1 includes: a plurality of heat transfer tubes 23, and an expansion valve-side manifold 21 to which the plurality of heat transfer tubes 23 are joined. The expansion valve-side manifold 21 has a first flow path 57, an inflow space 43, an inlet 61, and a plurality of insertion spaces 46. The first flow path 57 is used to allow refrigerant to flow from one end 41 to the other end 42 along the length direction 25 of the manifold. The inflow space 43 is adjacent to one end 41 of the first flow path 57. The inlet 61 is used to allow refrigerant to flow from the inflow space 43 to one end 41 of the first flow path 57. The plurality of insertion spaces 46 are arranged along the length direction 25 of the manifold, and one end of each of the plurality of heat transfer tubes 23 is disposed in one of the plurality of insertion spaces 46. The plurality of insertion spaces 46 includes: a first end-side insertion space 91, a second end-side insertion space 92, a first other end-side insertion space 93, a second other end-side insertion space 94, and a plurality of intermediate-side insertion spaces 95. The first end-side insertion space 91 is disposed on the side closest to the first end 41 and is adjacent to the inflow space 43. The second end-side insertion space 92 is adjacent to the first end-side insertion space 91. The first other end-side insertion space 93 is disposed on the side closest to the other end 42. The second other end-side insertion space 94 is adjacent to the first other end-side insertion space 93. The plurality of intermediate insertion spaces 95 are insertion spaces that are different from the first end-side insertion space 91, the second end-side insertion space 92, the first other end-side insertion space 93, and the second other end-side insertion space 94 among the plurality of insertion spaces 46.

[0070] The expansion valve side manifold 21 has a first end-side connecting flow path 106, a second end-side connecting flow path 107, a first end-side inlet hole 101, a second end-side inlet hole 102, a first second end-side inlet hole 103, a second second end-side inlet hole 104, and a plurality of middle-side inlet holes 105. The first end-side connecting flow path 106 connects the first end-side insertion space 91 with the second end-side insertion space 92. The second end-side connecting flow path 107 connects the first second end-side insertion space 93 with the second second end-side insertion space 94. The first end-side inlet hole 101 connects the inflow space 43 with the first end-side insertion space 91. The second end-side inlet hole 102 connects the first flow path 57 with the second end-side insertion space 92. The first second end-side inlet hole 103 connects the first flow path 57 with the first second end-side insertion space 93. The second end side inlet hole 104 connects the first flow path 57 with the second end side insertion space 94. Multiple middle side inlet holes 105 connect multiple middle side insertion spaces 95 to the first flow path 57 respectively.

[0071] At this time, even when liquid refrigerant is retained in the inflow space 43, the heat exchanger of Embodiment 1 can still allow liquid refrigerant flowing from the inflow space 43 into the first end-side insertion space 91 via the first end-side inlet hole 101 to flow into the second end-side insertion space 92 via the end-side connecting flow path 106. Therefore, the heat exchanger of Embodiment 1 can suppress the situation where more liquid refrigerant flows in the heat transfer tube inserted into the first end-side insertion space 91 than in other heat transfer tubes, i.e., flow deviation. Furthermore, even when liquid refrigerant is retained in the upper region 97 of the first flow path 57, the heat exchanger of Embodiment 1 can still allow liquid refrigerant flowing from the upper region 97 into the first other end-side insertion space 93 via the first other end-side inlet hole 103 to flow into the second other end-side insertion space 94 via the other end-side connecting flow path 107. Therefore, the heat exchanger of Embodiment 1 can suppress the situation where more liquid refrigerant flows in the heat transfer tube inserted into the insertion space 93 at the other end of the first heat transfer tube 23 than in other heat transfer tubes, i.e., flow deviation.

[0072] On the other hand, in the heat exchanger of Embodiment 1 described above, both a first end-side inlet hole 101 and a second end-side inlet hole 102 are formed simultaneously. However, it is also possible to form only one of the first end-side inlet hole 101 and the second end-side inlet hole 102, without forming the other. Furthermore, in the heat exchanger of Embodiment 1 described above, both a first other end-side inlet hole 103 and a second other end-side inlet hole 104 are formed simultaneously. However, it is also possible to form only one of the first other end-side inlet hole 103 and the second other end-side inlet hole 104, without forming the other.

[0073] Example 2

[0074] Figure 7 This is a schematic longitudinal cross-sectional view of the expansion valve side manifold 111 of the heat exchanger in Embodiment 2. Compared with the expansion valve side manifold 21 of the heat exchanger in Embodiment 1, the expansion valve side manifold 111 of the heat exchanger in Embodiment 2 does not have a second first end side inlet hole 102 and a second other end side inlet hole 104, but the other parts are the same as the expansion valve side manifold 21 described above. That is, the expansion valve side manifold 111 is formed such that the inlet hole plate member 76 does not have an inlet hole that connects the second first end side insertion space 92 to the first flow path 57, and the inlet hole plate member 76 does not have an inlet hole that connects the second other end side insertion space 94 to the first flow path 57.

[0075] When the heat exchanger of Example 2 functions as an evaporator, similar to the heat exchanger of Example 1 described above, liquid refrigerant remains in the inflow space 43 regardless of the amount of refrigerant circulating in the refrigerant circuit 4. When the liquid refrigerant remains in the inflow space 43, the flow rate of the liquid refrigerant in the low-pressure gas-liquid two-phase refrigerant flowing into the first end-side insertion space 91 via the first end-side inlet 101 is greater than the flow rate of the liquid refrigerant flowing into the plurality of intermediate-side insertion spaces 95. Figure 8 This is a cross-sectional view showing the flow of low-pressure gas-liquid two-phase refrigerant (especially liquid refrigerant) into the insertion space 91 at the first end of the heat exchanger in Example 2. Figure 8 As shown, the heat exchanger of Embodiment 2, by forming an end-side connecting flow path 106, allows a portion of the flow rate of the liquid refrigerant flowing into the first end-side insertion space 91 to flow out through the end-side connecting flow path 106 to the second end-side insertion space 92. Therefore, the heat exchanger of Embodiment 2 can make the flow rate of the liquid refrigerant flowing into the heat transfer tubes inserted into the first end-side insertion space 91 in the plurality of heat transfer tubes 23 close to the flow rate of the liquid refrigerant flowing into the heat transfer tubes inserted into the plurality of middle-side insertion spaces 95, and can suppress the deflection of the refrigerant flowing into the plurality of heat transfer tubes 23.

[0076] In the heat exchanger of Embodiment 1 described above, the low-pressure gas-liquid two-phase refrigerant flows into the second-first-end-side insertion space 92 through both the second-first-end-side inlet hole 102 and the end-side connecting flow path 106. In this case, the flow rate of the liquid refrigerant in the low-pressure gas-liquid two-phase refrigerant flowing into the second-first-end-side insertion space 92 is greater than the flow rate of the liquid refrigerant flowing into the plurality of intermediate-side insertion spaces 95. In the heat exchanger of Embodiment 2, since the second-first-end-side inlet hole 102 is not formed, the flow rate of the liquid refrigerant flowing into the second-first-end-side insertion space 92 can be reduced. Therefore, the flow rate of the liquid refrigerant in the low-pressure gas-liquid two-phase refrigerant flowing into the second-first-end-side insertion space 92 can be made close to the flow rate of the liquid refrigerant flowing into the plurality of intermediate-side insertion spaces 95. Furthermore, the flow rate of the liquid refrigerant flowing into the heat transfer tubes inserted into the second-first-end-side insertion space 92 in the plurality of heat transfer tubes 23 can be made close to the flow rate of the liquid refrigerant flowing into the heat transfer tubes inserted into the plurality of intermediate-side insertion spaces 95. Therefore, the heat exchanger of Example 2 can suppress the deflection of refrigerant flowing to the multiple heat transfer tubes 23.

[0077] Similar to the heat exchanger of Embodiment 1 described above, when the refrigerant charge circulating in the refrigerant circuit 4 is high, liquid refrigerant may sometimes stagnate in the upper region 97 of the first flow path 57 of the heat exchanger of Embodiment 2. When liquid refrigerant stagnates in the upper region 97, the flow rate of liquid refrigerant in the low-pressure gas-liquid two-phase refrigerant flowing into the first other end side insertion space 93 via the first other end side inlet hole 103 is greater than the flow rate of liquid refrigerant flowing from the first flow path 57 into the plurality of middle side insertion spaces 95. Figure 9 This is a cross-sectional view showing the flow of low-pressure gas-liquid two-phase refrigerant (especially liquid refrigerant) into the insertion space 93 at the other end of the heat exchanger in Example 2. Figure 9 As shown, the heat exchanger of Embodiment 2 has a flow path 107 connected to the other end side, thereby allowing a portion of the liquid refrigerant flowing into the first other end side insertion space 93 via the first other end side inlet hole 103 to flow out to the second other end side insertion space 94. Therefore, the heat exchanger of Embodiment 2 can make the flow rate of liquid refrigerant flowing into the heat transfer tubes inserted into the first other end side insertion space 93 in the plurality of heat transfer tubes 23 close to the flow rate of liquid refrigerant flowing into the heat transfer tubes inserted into the plurality of middle side insertion spaces 95, and can suppress the deflection of refrigerant flowing to the plurality of heat transfer tubes 23.

[0078] In the heat exchanger of Embodiment 1 described above, there is a situation where the low-pressure gas-liquid two-phase refrigerant flows into the second other-end-side insertion space 94 through both the second other-end-side inlet hole 104 and the other-end-side connecting flow path 107. There is a situation where the flow rate of the liquid refrigerant in the low-pressure gas-liquid two-phase refrigerant flowing into the second other-end-side insertion space 94 is greater than the flow rate of the liquid refrigerant flowing into the plurality of intermediate-side insertion spaces 95. Since the heat exchanger of Embodiment 2 does not have the second other-end-side inlet hole 104, the flow rate of the liquid refrigerant flowing into the second other-end-side insertion space 94 can be reduced, making the flow rate of the liquid refrigerant flowing into the second other-end-side insertion space 94 close to the flow rate of the liquid refrigerant flowing into the plurality of intermediate-side insertion spaces 95. Therefore, the heat exchanger of Embodiment 2 can make the flow rate of the liquid refrigerant flowing into the heat transfer tubes inserted into the second first-end-side insertion space 92 of the plurality of heat transfer tubes 23 close to the flow rate of the liquid refrigerant flowing into the heat transfer tubes inserted into the plurality of intermediate-side insertion spaces 95. Therefore, the heat exchanger of Example 2 can suppress the deflection of refrigerant flowing to the multiple heat transfer tubes 23.

[0079] Example 3

[0080] Figure 10 This is a schematic longitudinal cross-sectional view of the expansion valve side manifold 112 of the heat exchanger in Embodiment 3. Compared with the expansion valve side manifold 21 of the heat exchanger in Embodiment 1, the expansion valve side manifold 112 of the heat exchanger in Embodiment 3 does not have a first end-side inlet hole 101 and a first other end-side inlet hole 103, but the other parts are the same as the expansion valve side manifold 21. That is, the expansion valve side manifold 112 is formed such that the inlet hole plate member 76 does not have an inlet hole that connects the first end-side insertion space 91 and the inflow space 43, and the inlet hole plate member 76 does not have an inlet hole that connects the first other end-side insertion space 93 and the first flow path 57.

[0081] When the heat exchanger of Embodiment 3 functions as an evaporator, under the condition of a low circulation rate of refrigerant in the refrigerant circuit 4 with a small amount of refrigerant, the flow rate of the gas-liquid two-phase refrigerant flowing from the inlet space 43 into the first flow path 57 via the inlet 61 is relatively slow. Therefore, in the heat exchanger of Embodiment 3, the flow rate of the low-pressure gas-liquid two-phase refrigerant rising in the first flow path 57 is relatively slow. When the flow rate of the low-pressure gas-liquid two-phase refrigerant rising in the first flow path 57 is slow, the liquid refrigerant in the low-pressure gas-liquid two-phase refrigerant rising in the first flow path 57 may sometimes remain in the lower end region 96 of the first flow path 57 due to gravity. When the liquid refrigerant remains in the lower end region 96, the flow rate of the liquid refrigerant in the low-pressure gas-liquid two-phase refrigerant flowing into the second end side insertion space 92 via the second end side inlet hole 102 is sometimes greater than the flow rate of the liquid refrigerant flowing from the first flow path 57 into the plurality of middle side insertion spaces 95. Figure 11This is a cross-sectional view showing the flow of low-pressure gas-liquid two-phase refrigerant (especially liquid refrigerant) into the insertion space 92 at the second end side of the heat exchanger in Example 3. Figure 11 As shown, the heat exchanger of Embodiment 3, by forming an end-side connecting flow path 106, allows a portion of the flow rate of the liquid refrigerant flowing into the second end-side insertion space 92 to flow out through the end-side connecting flow path 106 to the first end-side insertion space 91. Therefore, the heat exchanger of Embodiment 3 can make the flow rate of the liquid refrigerant flowing into the heat transfer tubes inserted into the second end-side insertion space 92 in the plurality of heat transfer tubes 23 close to the flow rate of the liquid refrigerant flowing into the heat transfer tubes inserted into the plurality of middle-side insertion spaces 95, and can suppress the deflection of the refrigerant flowing into the plurality of heat transfer tubes 23.

[0082] In the heat exchanger of Embodiment 1 described above, the low-pressure gas-liquid two-phase refrigerant flows into the first-end-side insertion space 91 through both the first-end-side inlet hole 101 and the end-side connecting flow path 106. In this case, the flow rate of the liquid refrigerant in the low-pressure gas-liquid two-phase refrigerant flowing into the first-end-side insertion space 91 is greater than the flow rate of the liquid refrigerant flowing into each of the plurality of intermediate-side insertion spaces 95. In the heat exchanger of Embodiment 3, since the first-end-side inlet hole 101 is not formed, the flow rate of the liquid refrigerant flowing into the first-end-side insertion space 91 can be reduced. Therefore, the flow rate of the liquid refrigerant flowing into the first-end-side insertion space 91 can be made close to the flow rate of the liquid refrigerant flowing into the plurality of intermediate-side insertion spaces 95. Furthermore, the flow rate of the liquid refrigerant flowing into the heat transfer tubes inserted into the first-end-side insertion space 91 in the plurality of heat transfer tubes 23 can be made close to the flow rate of the liquid refrigerant flowing into the heat transfer tubes inserted into the plurality of intermediate-side insertion spaces 95. Therefore, the heat exchanger of Example 3 can suppress the deflection of refrigerant flowing to the multiple heat transfer tubes 23.

[0083] Similar to the heat exchanger in Embodiment 1 described above, when the refrigerant charge circulating in the refrigerant circuit 4 is high and the amount of refrigerant circulating is large, liquid refrigerant may sometimes stagnate in the upper region 97 of the first flow path 57. When liquid refrigerant stagnates in the upper region 97, the flow rate of liquid refrigerant flowing into the second other end side insertion space 94 via the second other end side inlet hole 104 may sometimes be greater than the flow rate of liquid refrigerant flowing into the plurality of middle side insertion spaces 95 from the first flow path 57. Figure 12 This is a cross-sectional view showing the flow of low-pressure gas-liquid two-phase refrigerant (especially liquid refrigerant) into the insertion space 94 at the second other end of the heat exchanger in Example 3. Figure 12As shown, the heat exchanger of Embodiment 3 has a flow path 107 connected to the other end side, thereby allowing a portion of the liquid refrigerant flowing into the second other end side insertion space 94 via the second other end side inlet hole 104 to flow out to the first other end side insertion space 93. Therefore, the heat exchanger of Embodiment 3 can make the flow rate of liquid refrigerant flowing into the heat transfer tubes inserted into the second other end side insertion space 94 in the plurality of heat transfer tubes 23 close to the flow rate of liquid refrigerant flowing into the heat transfer tubes inserted into the plurality of middle side insertion spaces 95, and can suppress the deflection of refrigerant flowing to the plurality of heat transfer tubes 23.

[0084] In the heat exchanger of Embodiment 1 described above, the low-pressure gas-liquid two-phase refrigerant flows into the first other-end-side insertion space 93 through both the first other-end-side inlet hole 103 and the other-end-side connecting flow path 107. There is a situation where the flow rate of the liquid refrigerant in the low-pressure gas-liquid two-phase refrigerant flowing into the first other-end-side insertion space 93 is greater than the flow rate of the liquid refrigerant flowing into the plurality of intermediate-side insertion spaces 95. In the heat exchanger of Embodiment 3, since the first other-end-side inlet hole 103 is not formed, the flow rate of the liquid refrigerant flowing into the first other-end-side insertion space 93 can be reduced. Therefore, the flow rate of the liquid refrigerant flowing into the second other-end-side insertion space 94 can be made close to the flow rate of the liquid refrigerant flowing into each of the plurality of intermediate-side insertion spaces 95. Furthermore, the flow rate of liquid refrigerant flowing into the heat transfer tubes 23 inserted into the first other end side insertion space 93 can be made close to the flow rate of liquid refrigerant flowing into the heat transfer tubes inserted into the middle side insertion spaces 95 of the plurality of heat transfer tubes 23. Therefore, the heat exchanger of Embodiment 3 can suppress the deflection of refrigerant flowing to the plurality of heat transfer tubes 23.

[0085] On the other hand, the heat exchanger of Embodiment 3 described above does not have a first end-side inlet hole 101 but has a second end-side inlet hole 102. However, it may also be formed with a first end-side inlet hole 101 but without a second end-side inlet hole 102, similar to the heat exchanger of Embodiment 2 described above. In addition, the heat exchanger of Embodiment 3 described above does not have a first other end-side inlet hole 103 but has a second other end-side inlet hole 104. However, it may also be formed with a first other end-side inlet hole 103 but without a second other end-side inlet hole 104, similar to the heat exchanger of Embodiment 2 described above.

[0086] Example 4

[0087] Figure 13 This is a cross-sectional view showing the first end-side insertion space 91 and the second end-side insertion space 92 of the heat exchanger in Embodiment 4. Figure 13As shown, in the heat exchanger of Embodiment 4, one heat transfer tube inserted into the first end-side insertion space 91 among the plurality of heat transfer tubes 23 of the heat exchanger of Embodiment 1 is replaced with two heat transfer tubes 121. Furthermore, in the heat exchanger of Embodiment 4, one heat transfer tube inserted into the second end-side insertion space 92 among the plurality of heat transfer tubes 23 of the heat exchanger of Embodiment 1 is replaced with two heat transfer tubes 122. Figure 14 This is a cross-sectional view showing the insertion space 93 at the first other end and the insertion space 94 at the second other end of the heat exchanger in Embodiment 4. Further, as... Figure 14 As shown, in the heat exchanger of Embodiment 4, one heat transfer tube inserted into the first other end side insertion space 93 among the multiple heat transfer tubes 23 of the heat exchanger of Embodiment 1 is replaced with two heat transfer tubes 123. Further, in the heat exchanger of Embodiment 4, one heat transfer tube inserted into the second other end side insertion space 94 among the multiple heat transfer tubes 23 of the heat exchanger of Embodiment 1 is replaced with two heat transfer tubes 124. Similar to the heat exchanger of Embodiment 1, each of the multiple middle side insertion spaces 95 inserts one of the multiple heat transfer tubes 23.

[0088] When the heat exchanger of Embodiment 4 functions as an evaporator, the liquid refrigerant in the low-pressure gas-liquid two-phase refrigerant flowing into one of the two heat transfer tubes 121 is introduced into the two heat transfer tubes 121 in such a way that the flow rate of the liquid refrigerant flowing into one of the two heat transfer tubes 121 is approximately equal to the flow rate of the liquid refrigerant flowing into the other of the two heat transfer tubes 121. The liquid refrigerant is introduced into the two heat transfer tubes 122 in such a way that the flow rate of the liquid refrigerant flowing into one of the two heat transfer tubes 122 is approximately equal to the flow rate of the liquid refrigerant flowing into the other of the two heat transfer tubes 122. The liquid refrigerant is introduced into the two heat transfer tubes 123 in such a way that the flow rate of the liquid refrigerant flowing into one of the two heat transfer tubes 123 is approximately equal to the flow rate of the liquid refrigerant flowing into the other of the two heat transfer tubes 123, and the liquid refrigerant is introduced into the two heat transfer tubes 123 in such a way that the flow rate of the liquid refrigerant flowing into one of the two heat transfer tubes 123 is approximately equal to the flow rate of the liquid refrigerant flowing into the other of the two heat transfer tubes 123. The liquid refrigerant is inserted into the space 94 from the second other end side in such a way that the flow rate of the liquid refrigerant flowing into one of the two heat transfer tubes 124 is approximately equal to the flow rate of the liquid refrigerant flowing into the other of the two heat transfer tubes 124.

[0089] The heat exchanger of Embodiment 1 described above sometimes does not adequately suppress the deviance of the refrigerant flow to the plurality of heat transfer tubes 23. For example, in the heat exchanger of Embodiment 1 described above, sometimes the flow rate of the gas-liquid two-phase refrigerant flowing into the heat transfer tubes inserted into the first end-side insertion space 91 of the plurality of heat transfer tubes 23 is greater than the flow rate of the gas-liquid two-phase refrigerant flowing into the heat transfer tubes inserted into each of the plurality of middle-side insertion spaces 95. In addition, in the heat exchanger of Embodiment 1 described above, sometimes the flow rate of the gas-liquid two-phase refrigerant flowing into the heat transfer tubes inserted into the second end-side insertion space 92 of the plurality of heat transfer tubes 23 is greater than the flow rate of the gas-liquid two-phase refrigerant flowing into the heat transfer tubes inserted into each of the plurality of middle-side insertion spaces 95. Furthermore, in the heat exchanger of Embodiment 1 described above, sometimes the flow rate of the gas-liquid two-phase refrigerant flowing into the heat transfer tubes inserted into the first other end side insertion space 93 of the plurality of heat transfer tubes 23 is greater than the flow rate of the gas-liquid two-phase refrigerant flowing into the heat transfer tubes inserted into each of the plurality of middle side insertion spaces 95. Also, in the heat exchanger of Embodiment 1 described above, sometimes the flow rate of the gas-liquid two-phase refrigerant flowing into the heat transfer tubes inserted into the second other end side insertion space 94 of the plurality of heat transfer tubes 23 is greater than the flow rate of the gas-liquid two-phase refrigerant flowing into the heat transfer tubes inserted into each of the plurality of middle side insertion spaces 95.

[0090] Because the gas-liquid two-phase refrigerant flows into the two heat transfer tubes 121 from the first end side insertion space 91, the flow rate of the gas-liquid two-phase refrigerant flowing into each of the two heat transfer tubes 121 is less than the flow rate of the gas-liquid two-phase refrigerant flowing into one heat transfer tube inserted into the first end side insertion space 91 in the heat exchanger of the above-described embodiment 1. Because the gas-liquid two-phase refrigerant flows into the two heat transfer tubes 122 from the second end side insertion space 92, the flow rate of the gas-liquid two-phase refrigerant flowing into each of the two heat transfer tubes 122 is less than the flow rate of the gas-liquid two-phase refrigerant flowing into one heat transfer tube inserted into the second end side insertion space 92 in the heat exchanger of the above-described embodiment 1. Because the gas-liquid two-phase refrigerant flows into the two heat transfer tubes 123 from the first other end insertion space 93, the flow rate of the gas-liquid two-phase refrigerant flowing into each of the two heat transfer tubes 123 is less than the flow rate of the gas-liquid two-phase refrigerant flowing into one of the heat transfer tubes 23 inserted into the first other end insertion space 93 in the heat exchanger of the above-described embodiment 1. Because the gas-liquid two-phase refrigerant flows into the two heat transfer tubes 124 from the second other end insertion space 94, the flow rate of the gas-liquid two-phase refrigerant flowing into each of the two heat transfer tubes 124 is less than the flow rate of the gas-liquid two-phase refrigerant flowing into one of the heat transfer tubes 23 inserted into the second other end insertion space 94 in the heat exchanger of the above-described embodiment 1. Therefore, even when the heat exchanger of Example 1 fails to adequately suppress the refrigerant flow deviation to the multiple heat transfer tubes 23, the heat exchanger of Example 4 can make the flow rate of the liquid refrigerant in the low-pressure gas-liquid two-phase refrigerant flowing into each heat transfer tube 121-124 close to the flow rate of the liquid refrigerant flowing into each heat transfer tube inserted into the multiple middle side insertion spaces 95 of the multiple heat transfer tubes 23, thereby suppressing the refrigerant flow deviation to the multiple heat transfer tubes 23.

[0091] On the other hand, in the heat exchanger of Embodiment 4 above, both a first end-side inlet hole 101 and a second end-side inlet hole 102 are formed simultaneously. However, similar to the heat exchangers of Embodiments 2 and 3 above, only one of the first end-side inlet hole 101 and the second end-side inlet hole 102 may be formed, without forming the other. Furthermore, in the heat exchanger of Embodiment 1 above, both a first other end-side inlet hole 103 and a second other end-side inlet hole 104 are formed simultaneously. However, similar to the heat exchangers of Embodiments 2 and 3 above, only one of the first other end-side inlet hole 103 and the second other end-side inlet hole 104 may be formed, without forming the other.

[0092] On the other hand, in the heat exchanger of Embodiment 4 above, two heat transfer tubes are inserted in each of the first end-side insertion space 91, the second end-side insertion space 92, the first other end-side insertion space 93, and the second other end-side insertion space 94. However, it is also possible that only one heat transfer tube is inserted in any one of the first end-side insertion space 91, the second end-side insertion space 92, the first other end-side insertion space 93, and the second other end-side insertion space 94. In addition, in the heat exchanger of Embodiment 4 above, one heat transfer tube is inserted in each of the plurality of middle-side insertion spaces 95. However, it is also possible that the number of heat transfer tubes inserted in each of these spaces is the same as the number of heat transfer tubes inserted in the first end-side insertion space 91, the second end-side insertion space 92, the first other end-side insertion space 93, and the second other end-side insertion space 94.

[0093] Example 5

[0094] Figure 15 This is a schematic longitudinal cross-sectional view of the expansion valve side manifold 130 of the heat exchanger in Embodiment 5. (See attached image.) Figure 15 As shown, in the heat exchanger of Embodiment 5, the expansion valve side manifold 21 of the heat exchanger of Embodiment 1 is replaced with another expansion valve side manifold 130. The heat exchanger of Embodiment 5 also includes three branch pipes 131-133, and also includes a distributor (not shown). The distributor is connected to the refrigerant piping 17 and to the three branch pipes 131-133. The expansion valve side manifold 130 includes three expansion valve side manifold portions 134-136. The three expansion valve side manifold portions 134-136 are arranged in the manifold length direction 25.

[0095] Similar to the expansion valve side manifold 21 described above, the first expansion valve side manifold portion 134 of the three expansion valve side manifold portions 134-136 includes: an inflow space 43, a refrigerant piping through hole 44, a circulation path 45, an inlet 61, multiple insertion spaces 46, multiple heat transfer tube through holes 47, and multiple inlet holes 62. By inserting the first branch pipe 131 into the refrigerant piping through hole 44, the first expansion valve side manifold portion 134 is connected to the distributor via the first branch pipe 131.

[0096] Similar to the expansion valve side manifold 21 described above, the second expansion valve side manifold portion 135 of the three expansion valve side manifold portions 134-136 includes: an inflow space 43, a refrigerant piping through hole 44, a circulation path 45, an inlet 61, multiple insertion spaces 46, multiple heat transfer tube through holes 47, and multiple inlet holes 62. The second expansion valve side manifold portion 135 is connected to the distributor via the second branch pipe 132 by inserting the second branch pipe 132 into the refrigerant piping through hole 44.

[0097] Similar to the expansion valve side manifold 21 described above, the third expansion valve side manifold portion 136 of the three expansion valve side manifold portions 134-136 includes: an inflow space 43, a refrigerant piping through hole 44, a circulation path 45, an inlet 61, multiple insertion spaces 46, multiple heat transfer tube through holes 47, and multiple inlet holes 62. The third expansion valve side manifold portion 136 is connected to the distributor via the third branch pipe 133 by inserting the third branch pipe 133 into the refrigerant piping through hole 44.

[0098] The plurality of heat transfer tubes 23 include a plurality of first heat transfer tubes 137, a plurality of second heat transfer tubes 138, and a plurality of third heat transfer tubes 139. The plurality of first heat transfer tubes 137, second heat transfer tubes 138, and third heat transfer tubes 139 are arranged along the length direction 25 of the manifold. The plurality of first heat transfer tubes 137 are connected to the first expansion valve side manifold portion 134 such that one end of each first heat transfer tube 137 is disposed in a plurality of insertion spaces 46 of the first expansion valve side manifold portion 134. The plurality of second heat transfer tubes 138 are connected to the second expansion valve side manifold portion 135 such that one end of each second heat transfer tube 138 is disposed in a plurality of insertion spaces 46 of the second expansion valve side manifold portion 135. The plurality of third heat transfer tubes 139 are connected to the third expansion valve side manifold portion 136 such that one end of each third heat transfer tube 139 is disposed in a plurality of insertion spaces 46 of the third expansion valve side manifold portion 136.

[0099] That is, the heat exchanger of Embodiment 5 includes three heat exchange sections 141-143. The first heat exchange section 141 of the three heat exchange sections 141-143 includes: a first branch pipe 131, a first expansion valve side manifold portion 134, and a plurality of first heat transfer pipes 137. The second heat exchange section 142 of the three heat exchange sections 141-143 includes: a second branch pipe 132, a second expansion valve side manifold portion 135, and a plurality of second heat transfer pipes 138. The third heat exchange section 143 of the three heat exchange sections 141-143 includes: a third branch pipe 133, a third expansion valve side manifold portion 136, and a plurality of third heat transfer pipes 139. In this case, the three heat exchange sections 141-143 are arranged along the length direction 25 of the manifold.

[0100] When the heat exchanger of Embodiment 5 functions as an evaporator, the distributor diverts the liquid refrigerant in the low-pressure gas-liquid two-phase refrigerant supplied via refrigerant piping 17 to ensure that the flow rates are equal, and supplies it to the three expansion valve side manifold sections 134-136 via three branch pipes 131-133 respectively. Similar to the expansion valve side manifold 21 of the heat exchanger of Embodiment 1 described above, the first expansion valve side manifold section 134 diverts the low-pressure gas-liquid two-phase refrigerant supplied via the first branch pipe 131 to the multiple first heat transfer pipes 137 in such a way that the flow rates of liquid refrigerant in the low-pressure gas-liquid two-phase refrigerant flowing into the multiple first heat transfer pipes 137 are equal to each other. Similar to the expansion valve side manifold 21 of the heat exchanger in Embodiment 1 described above, the second expansion valve side manifold portion 135 diverts the low-pressure gas-liquid two-phase refrigerant supplied via the second branch pipe 132 to the multiple second heat transfer tubes 138 in such a way that the flow rates of the liquid refrigerant flowing into the multiple second heat transfer tubes 138 are equal. Similarly to the expansion valve side manifold 21 of the heat exchanger in Embodiment 1 described above, the third expansion valve side manifold portion 136 diverts the low-pressure gas-liquid two-phase refrigerant supplied via the third branch pipe 133 to the multiple third heat transfer tubes 139 in such a way that the flow rates of the liquid refrigerant flowing into the multiple third heat transfer tubes 139 are equal.

[0101] The heat exchanger of Embodiment 5 allows for a smaller number of heat transfer tubes connected to the expansion valve side manifold sections 134-136 compared to the number of heat transfer tubes connected to the expansion valve side manifold 21 in the heat exchanger of Embodiment 1. Because the heat exchanger of Embodiment 5 has fewer heat transfer tubes connected to the expansion valve side manifold sections 134-136, it reduces the difficulty of diverting flow to the heat transfer tubes in these sections, further suppressing flow deviation to the multiple heat transfer tubes 23. Furthermore, in the heat exchanger of Embodiment 1, if the number of multiple heat transfer tubes 23 connected to the expansion valve side manifold 21 increases, the length of the first flow path 57 becomes longer, making it difficult for liquid refrigerant to reach the upper region 97 of the first flow path 57 under the influence of gravity. Even when there are many heat transfer tubes 23, the heat exchanger of Embodiment 5 can ensure that the amount of liquid refrigerant reaching the upper region 97 of the first flow path 57 of each of the three expansion valve side manifold sections 134-136 is sufficient, and can suppress the deflection of the multiple heat transfer tubes 23.

[0102] On the other hand, the heat exchanger of Embodiment 5 described above has three heat exchange sections 141-142, but it may also have two heat exchange sections, or even four or more heat exchange sections. In this case, the heat exchanger of Embodiment 5 described above can further suppress the flow deviation of the multiple heat transfer tubes 23.

[0103] On the other hand, the three expansion valve side manifold portions 134-136 of the heat exchanger in Embodiment 5 are formed in the same manner as the expansion valve side manifold 21 of the heat exchanger in Embodiment 1, but they can also be formed in the same manner as the expansion valve side manifolds of the heat exchangers in other embodiments. In this case, the heat exchanger in Embodiment 5 can also suppress the flow deviation to the plurality of heat transfer tubes 23.

[0104] On the other hand, the three heat exchange sections 141-142 of the heat exchanger in Embodiment 5 are arranged in the manifold length direction 25, but they can also be arranged in a direction different from the manifold length direction 25. For example, the ventilation direction 20 can be used as the direction in which the three heat exchange sections 141-142 are arranged. In this case, the heat exchanger in Embodiment 5 can also reduce the number of heat transfer tubes connected to each of the three expansion valve side manifold sections 134-136, or ensure the amount of liquid refrigerant reaching the upper region 97 of the first flow path 57, thereby suppressing the flow deviation of the multiple heat transfer tubes 23.

[0105] On the other hand, the heat exchangers of the above embodiments 1 to 5 are arranged such that one end 42 is positioned above one end 41, but they can also be arranged such that one end 41 is positioned above the other end 42. In addition, the manifold length direction 25 is configured to be parallel to the vertical direction, but the manifold length direction 25 can also be configured not to be parallel to the vertical direction.

[0106] On the other hand, the heat exchangers of the above embodiments 1 to 5 form both an end-side connecting flow path 106 and an end-side connecting flow path 107. However, it is also possible to form only one of the end-side connecting flow path 106 and the end-side connecting flow path 107, without forming the other one. Even when the heat exchanger does not form an end-side connecting flow path 106, the flow rate of the liquid refrigerant flowing into the heat transfer tubes inserted into the first end-side insertion space 93 or the second end-side insertion space 94 of the plurality of heat transfer tubes 23 is close to the flow rate of the liquid refrigerant flowing into the heat transfer tubes inserted into the plurality of middle-side insertion spaces 95. Even without the formation of another end-side connecting flow path 107, the flow rate of the liquid refrigerant in the low-pressure gas-liquid two-phase refrigerant flowing into the heat transfer tubes 23 inserted into the first end-side insertion space 91 or the second end-side insertion space 92 is close to the flow rate of the liquid refrigerant flowing into the heat transfer tubes inserted into the multiple middle-side insertion spaces 95.

[0107] On the other hand, the expansion valve side manifold 21 of the heat exchangers in embodiments 1-5 described above is formed with a first flow path 57, a second flow path 58, a first reversible flow path 51, and a second reversible flow path 52, but it is also possible not to form the second flow path 58, the first reversible flow path 51, and the second reversible flow path 52. Even when the heat exchanger does not form the second flow path 58, the first reversible flow path 51, and the second reversible flow path 52, the liquid refrigerant will remain in the inflow space 43, the lower region 96, or the upper region 97. Even when the heat exchanger does not form the second flow path 58, the first reversible flow path 51, and the second reversible flow path 52, it is able to suppress the deflection of the liquid refrigerant flowing to the multiple heat transfer tubes 23, just like the heat exchangers in embodiments 1-5 described above.

[0108] The embodiments described above are examples, but the embodiments are not limited to the above content. Furthermore, the structural elements described above include structural elements that are readily conceived by those skilled in the art, substantially the same, and within the so-called equivalent range. Moreover, the structural elements described above can be appropriately combined. Furthermore, at least one of various omissions, substitutions, and modifications can be made to the structural elements without departing from the spirit of the embodiments.

[0109] Symbol Explanation

[0110] 1: Outdoor heat exchanger (heat exchanger)

[0111] 21, 111, 112, 130: Expansion valve side manifold (manifold)

[0112] 23: Heat transfer tube

[0113] 25: Manifold length direction (length direction)

[0114] 41: One end

[0115] 42: The other end

[0116] 43: Inflow Space

[0117] 45: Circulating flow path (branching flow path)

[0118] 46: Multiple insertion spaces

[0119] 57: First flow path

[0120] 61: Inlet

[0121] 62: Multiple inlet holes

[0122] 91: Insertion space at the first end side

[0123] 92: Insertion space at the second end side

[0124] 93: Insertion space at the other end of the first end

[0125] 94: Insertion space at the other end of the second end

[0126] 95: Multiple mid-side insertion spaces

[0127] 96: Lower area

[0128] 97: Upper area

[0129] 101: First end side inlet hole

[0130] 102: Second end side inlet hole

[0131] 103: The other end side inlet hole of the first one

[0132] 104: The second end side inlet hole

[0133] 105: Multiple center-side inlet holes

[0134] 106: One end side connected flow path

[0135] 107: The other end side connects to the flow path

[0136] 141~143: Three heat exchange sections.

Claims

1. A heat exchanger, characterized in that, have: Multiple heat transfer tubes; and A manifold, which connects the plurality of heat transfer tubes. The manifold is formed as follows: A flow branch path is provided to allow refrigerant to flow from one end side to the other end side along the length of the manifold. An inflow space, which is adjacent to one end of the manifold in the length direction of the branch flow path, is used to allow refrigerant to flow into the branch flow path; An inlet that allows refrigerant to flow from the inlet space into the branch flow path at one end of the manifold along its length; as well as Multiple insertion spaces are arranged along the length of the manifold, for one end of each of the multiple heat transfer tubes to be configured. The plurality of insertion spaces include: The first end side is inserted into the space, which is adjacent to the inflow space; The second end-side insertion space is adjacent to the first end-side insertion space; The first other end side insertion space is located at the side closest to the other end side; The second end-side insertion space is adjacent to the first end-side insertion space; and Multiple mid-side insertion spaces, which are different from the first end-side insertion space, the second end-side insertion space, the first other end-side insertion space, and the second other end-side insertion space. The manifold forms at least one of an end-side connecting flow path and an other end-side connecting flow path. The first end-side connecting flow path connects the first end-side insertion space with the second end-side insertion space, and the other end-side connecting flow path connects the other first end-side insertion space with the other second end-side insertion space. The manifold also has multiple central inlet holes, which connect the multiple central insertion spaces to the branch flow paths respectively. When the aforementioned end-side connecting flow path is formed, the manifold also forms at least one of a first end-side inlet hole and a second end-side inlet hole. The first end-side inlet hole connects the inflow space to the first end-side insertion space, and the second end-side inlet hole connects the branch flow path to the second end-side insertion space. When the other end side connecting flow path is formed, the manifold also forms at least one of a first other end side inlet hole and a second other end side inlet hole, the first other end side inlet hole connecting the flow path to the first other end side insertion space, and the second other end side inlet hole connecting the flow path to the second other end side insertion space.

2. A heat exchanger, characterized in that, have: Multiple heat transfer tubes; and A manifold, which connects the plurality of heat transfer tubes. The manifold is formed as follows: A flow branch path is provided to allow refrigerant to flow from one end side to the other end side along the length of the manifold. The inflow space is located at one end of the manifold along the length of the branch flow path; An inlet that allows refrigerant to flow from the inlet space into the branch flow path at one end of the manifold along its length; as well as Multiple insertion spaces are arranged along the length of the manifold, for one end of each of the multiple heat transfer tubes to be configured. The plurality of insertion spaces include: The first end side is inserted into the space, which is adjacent to the inflow space; The second end-side insertion space is adjacent to the first end-side insertion space; and Multiple mid-side insertion spaces, which are different from the first end-side insertion space and the second end-side insertion space. The manifold is formed as follows: Multiple center-side inlet holes, which connect the flow branch path to the multiple center-side insertion spaces respectively; and A flow path is provided at one end, which connects the first end-side insertion space with the second end-side insertion space. The manifold has at least one of a first end-side inlet hole and a second end-side inlet hole, the first end-side inlet hole connecting the inflow space to the first end-side insertion space, and the second end-side inlet hole connecting the branch flow path to the second end-side insertion space.

3. The heat exchanger according to claim 2, characterized in that, The manifold is configured such that the inlet hole for communicating the inflow space with the first end-side insertion space is not formed between the inflow space and the first end-side insertion space.

4. The heat exchanger according to claim 3, characterized in that, The plurality of insertion spaces also include: A first, other end-side insertion space, which is disposed closest to the other end-side; and The second insertion space is located at the other end of the first insertion space. The manifold forms a flow path with another end side connection, which connects the first other end side insertion space with the second other end side insertion space. The manifold also has at least one of a first other end side inlet hole and a second other end side inlet hole, wherein the first other end side inlet hole connects the flow path to the first other end side insertion space, and the second other end side inlet hole connects the flow path to the second other end side insertion space.

5. The heat exchanger according to claim 4, characterized in that, The manifold is configured such that the inlet hole for connecting the branch flow path to the insertion space at the other end of the first flow path is not formed between the branch flow path and the insertion space at the other end of the first flow path.

6. The heat exchanger according to claim 3, characterized in that, The other end is positioned above the first end.

7. The heat exchanger according to claim 2, characterized in that, The first end side insertion space is provided with one end of two or more of the plurality of heat transfer tubes. The second end side insertion space is configured with one end of two or more of the plurality of heat transfer tubes.

8. The heat exchanger according to claim 4, characterized in that, The first end has one end of two or more of the plurality of heat transfer tubes inserted into the space. The other end of the second end is inserted into the space where one end of two or more of the plurality of heat transfer tubes is disposed.

9. The heat exchanger according to claim 7, characterized in that, The manifold also forms a loop flow path, which connects the other end of the branch flow path with the first end of the branch flow path.

10. The heat exchanger according to claim 8, characterized in that, It has multiple heat exchange sections, each of which includes multiple heat transfer tubes and a manifold. The multiple heat exchange units are arranged in parallel.

11. The heat exchanger according to claim 10, characterized in that, The plurality of heat exchange units are stacked in the length direction of the manifold.

Images