Heat exchanger, air-conditioning device, and method for manufacturing heat exchanger

Abstract

Provided are a heat exchanger, an air-conditioning device, and a method for manufacturing the heat exchanger that can be easily brazed. An outdoor heat exchanger (11) is provided with: a plurality of flat tubes (28); a gas header (50) connected to the plurality of flat tubes (28); a gas refrigerant connection pipe (19a) connected to the gas header (50); and a connection section (58) provided at a connection portion between the gas header (50) and the gas refrigerant connection duct (19a), the connection section (58) containing a metal and a brazing material.

Description

Technical Field

[0001] This disclosure relates to heat exchangers, air conditioning units, and methods for manufacturing heat exchangers. Background Technology

[0002] Traditionally, heat exchangers with manifolds connected to multiple heat transfer tubes have been used in air conditioning units and the like. These heat exchangers typically have manifolds connected to refrigerant piping for supplying refrigerant.

[0003] For example, in the heat exchanger of an air conditioning unit described in Patent Document 1 (Japanese Patent Application Publication No. 2023-102026), the manifold and refrigerant piping are brazed together. Summary of the Invention

[0004] The problem that the invention aims to solve

[0005] Brazing of manifolds and refrigerant piping in heat exchangers can be performed by, for example, by feeding brazing filler metal to the joint between the manifolds and refrigerant piping while brazing. However, brazing can easily become complicated.

[0006] Methods for solving problems

[0007] The heat exchanger of the first viewpoint has multiple heat transfer tubes, a manifold, refrigerant piping, and connecting parts. The manifold connects to the multiple heat transfer tubes. The refrigerant piping connects to the manifold. The connecting parts are located at the connection between the manifold and the refrigerant piping. The connecting parts are independent of the manifold. The connecting parts are independent of the refrigerant piping. The connecting parts consist of metal and brazing filler metal.

[0008] In this heat exchanger, the manifold can be easily connected to the refrigerant piping because the brazing filler metal contained in the joint melts during brazing.

[0009] In the heat exchanger of the second perspective, the connecting part restricts the movement of the piping connection portion in the direction in which the piping connection portion extends. The piping connection portion is the connection portion of the refrigerant piping.

[0010] This heat exchanger can prevent refrigerant piping from coming loose during brazing in the furnace.

[0011] In the heat exchanger of the third viewpoint, the refrigerant piping is a circular tube, as in the heat exchanger of the first or second viewpoint. The connecting portion restricts the rotation of the piping connection section about the direction in which the piping connection section extends. The piping connection section is the connection part of the refrigerant piping.

[0012] In this heat exchanger, the rotation of the refrigerant piping around the axis during brazing in the furnace can be suppressed.

[0013] In the heat exchanger of the fourth viewpoint, as in any of the first to third viewpoints, the connecting portion includes a first connecting portion and a second connecting portion. The first connecting portion is fixed to the piping connection portion. The second connecting portion is fixed to the manifold. The piping connection portion is the connection portion of the refrigerant piping. The second connecting portion restricts the movement of the first connecting portion.

[0014] In this heat exchanger, the movement of the refrigerant piping relative to the manifold during brazing in the furnace can be limited by only two connections.

[0015] In the heat exchanger of the fifth viewpoint, when viewed from the direction extending from the piping connection portion, the first connection portion covers the periphery of the piping connection portion.

[0016] In this heat exchanger, brazing filler metal can be easily supplied around the piping connections during brazing in the furnace.

[0017] In the heat exchanger of the sixth viewpoint, compared to the heat exchangers of the fourth or fifth viewpoints, the first connecting portion has a first shaped portion partially disposed circumferentially on the piping connecting portion. The refrigerant piping is a circular pipe. The second connecting portion has a second shaped portion. The second shaped portion cooperates with the first shaped portion to restrict the rotation of the piping connecting portion with the direction in which the piping connecting portion extends as the axis of rotation.

[0018] In this heat exchanger, the rotation of the refrigerant piping around the axis during brazing in the furnace can be suppressed by two connecting parts.

[0019] The heat exchanger of the seventh viewpoint, in contrast to the heat exchanger of the sixth viewpoint, has a first connecting portion having a cylindrical member that covers the piping connection portion from all sides. The first shaped portion is an opening or notch provided in the cylindrical member. A second shaped portion is inserted radially into the opening or notch toward the piping connection portion.

[0020] In this heat exchanger, a second-shaped portion fixed to the second connection of the manifold is inserted into the opening or notch of the first connection of the refrigerant piping, which is a cylindrical component, thereby suppressing the rotation of the refrigerant piping.

[0021] In the heat exchanger of the eighth viewpoint, in the heat exchanger of the fourth or fifth viewpoint, the second connection part is fixed to the first connection part, or fixed to the piping connection part via the first connection part, or integrated with the first connection part.

[0022] In this heat exchanger, the movement of the refrigerant piping relative to the manifold during brazing in the furnace can be restricted.

[0023] In the heat exchanger of the ninth viewpoint, as in any of the first to eighth viewpoints, the manifold has a first manifold component. The first manifold component includes a connecting portion of the manifold. The first manifold component has a semi-circular portion that is semi-circular when viewed from the length direction of the first manifold component.

[0024] In this heat exchanger, the shape of the first manifold component when viewed from its length is semi-circular, which makes it easier to improve the pressure resistance of the manifold.

[0025] In the heat exchanger of the tenth viewpoint, in any of the heat exchangers of the first to ninth viewpoints, the refrigerant piping and manifolds do not contain brazing filler metal.

[0026] In this heat exchanger, even when the refrigerant piping and manifold do not contain brazing filler metal, in-furnace brazing can be performed using brazing filler metal contained in the connection portion provided at the connection between the manifold and the refrigerant piping.

[0027] The air conditioning unit of the eleventh viewpoint has a heat exchanger from any of the first to tenth viewpoints.

[0028] The air conditioning unit is easy to manufacture by using a heat exchanger with manifolds and refrigerant piping brazed in a furnace.

[0029] The twelfth viewpoint describes a method for manufacturing a heat exchanger having multiple heat transfer tubes, a manifold connected to the multiple heat transfer tubes, and refrigerant piping connected to the manifold. This method includes a positioning process and a brazing process. In the positioning process, a connecting part containing metal and brazing filler metal is provided at the connection between the manifold and the refrigerant piping, and the position of the refrigerant piping relative to the manifold is determined by the connecting part. In the brazing process, the refrigerant piping is brazed to the manifold while still positioned in the positioning process.

[0030] In this method of manufacturing the heat exchanger, brazing is performed with the position of the refrigerant pipe relative to the manifold determined by the connecting part, which melts the brazing filler metal contained in the connecting part. Therefore, the manifold and the refrigerant pipe can be easily joined while maintaining the position of the refrigerant pipe relative to the manifold.

[0031] The thirteenth viewpoint's method for manufacturing a heat exchanger uses a circular refrigerant pipe. In the positioning process, a connecting part is used to restrict the rotation of the pipe connection portion. The rotation of the pipe connection portion is with the direction of its extension as the axis of rotation. The pipe connection portion is the connection between the refrigerant pipe and the manifold. In the brazing process, the refrigerant pipe is brazed to the manifold under the restricted condition.

[0032] In the manufacturing method of this heat exchanger, it is possible to suppress the rotation of the refrigerant piping relative to the manifold during brazing.

[0033] The manufacturing method of the heat exchanger in the fourteenth viewpoint involves brazing in a furnace, as in the manufacturing method of the heat exchanger in the twelfth or thirteenth viewpoint.

[0034] In this method of manufacturing the heat exchanger, in-furnace brazing can be performed while maintaining the position of the refrigerant piping relative to the manifold. Attached Figure Description

[0035] Figure 1 This is a schematic diagram of the air conditioning unit.

[0036] Figure 2 This is a schematic 3D diagram of an outdoor heat exchanger.

[0037] Figure 3 This is a magnified view of a portion of the heat exchange section of an outdoor heat exchanger.

[0038] Figure 4 This is a schematic diagram showing the installation state of the heat transfer fins in the heat exchange section relative to the flat tube.

[0039] Figure 5 This is a simplified diagram illustrating the flow of refrigerant in an outdoor heat exchanger where the evaporator functions as the refrigerant.

[0040] Figure 6 This is a perspective view showing the connection between the gaseous refrigerant piping and the gas manifold.

[0041] Figure 7 This is a simplified exploded 3D diagram of the gas manifold.

[0042] Figure 8 This is a three-dimensional view of the connection between the gas manifold and the gas refrigerant piping.

[0043] Figure 9 This is an exploded three-dimensional view of the area near the connection between the gas manifold and the gas refrigerant piping.

[0044] Figure 10 This is a perspective view showing the case where the gas refrigerant connection piping is fixed with a first connection part.

[0045] Figure 11 This is a perspective view of the connection portion between the gas manifold and the gas refrigerant connection piping in another embodiment A.

[0046] Figure 12 This is an external view of the connection portion between the gas manifold and the gas refrigerant connection piping in other implementation method A.

[0047] Figure 13 This is a perspective view of the connection portion of the gas refrigerant connection piping in other embodiment A.

[0048] Figure 14 This is a perspective view of the connection portion between the gas manifold and the gas refrigerant connection piping in another embodiment B.

[0049] Figure 15 This is a perspective view of the connection portion between the gas manifold and the gas refrigerant connection piping in another embodiment B.

[0050] Figure 16 This is a perspective view of the connection portion between the gas manifold and the gas refrigerant connection piping in another embodiment F.

[0051] Figure 17 This is an external view of the connection portion between the gas manifold and the gas refrigerant connection piping in another embodiment F.

[0052] Figure 18 This is an external view of the connection portion between the gas manifold and the gas refrigerant connection piping in another embodiment G. Detailed Implementation

[0053] The following describes embodiments of the heat exchanger of this disclosure and the air conditioning unit using the heat exchanger.

[0054] (1) Structure of the air conditioning unit

[0055] The air conditioning unit 1 is described with reference to the attached drawings.

[0056] Figure 1 This is a schematic structural diagram of an air conditioning unit 1 having an outdoor heat exchanger 11 as an embodiment of the present disclosure.

[0057] Air conditioning unit 1 is a device that cools and heats a space by means of a vapor compression refrigeration cycle. The space to be refrigerated is, for example, the space within a building such as an office building, commercial facility, or residence. Furthermore, the air conditioning unit is only one example of a refrigerant cycle device; the heat exchanger disclosed herein can also be used in other refrigerant cycle devices, such as cold storage rooms, freezers, hot water supply units, and floor heating systems.

[0058] like Figure 1As shown, the air conditioning unit 1 mainly includes an outdoor unit 2, an indoor unit 9, a liquid refrigerant connecting pipe 4, a gaseous refrigerant connecting pipe 5, and a control unit 3 that controls the equipment constituting the outdoor unit 2 and the indoor unit 9. The liquid refrigerant connecting pipe 4 and the gaseous refrigerant connecting pipe 5 are refrigerant connecting pipes that connect the outdoor unit 2 and the indoor unit 9. In the air conditioning unit 1, the outdoor unit 2 and the indoor unit 9 are connected via the liquid refrigerant connecting pipe 4 and the gaseous refrigerant connecting pipe 5, thereby forming a refrigerant circuit 6.

[0059] In addition, Figure 1 In this system, the air conditioning unit 1 has one indoor unit 9, but the air conditioning unit 1 may also have multiple indoor units 9 connected to the outdoor unit 2 in parallel via liquid refrigerant connecting pipe 4 and gaseous refrigerant connecting pipe 5. Furthermore, the air conditioning unit 1 may also have multiple outdoor units 2. Additionally, the air conditioning unit 1 may be an integrated air conditioning unit in which the outdoor unit 2 and the indoor unit 9 are formed as one unit.

[0060] (1-1) Outdoor Unit

[0061] Outdoor unit 2 is located outside the space to be conditioned, such as near the roof of a building or the wall of a building.

[0062] The outdoor unit 2 mainly includes a liquid receiver 7, a compressor 8, a four-way switching valve 10, an outdoor heat exchanger 11, an outdoor expansion valve 12, a liquid-side shut-off valve 13 and a gas-side shut-off valve 14, and an outdoor fan 16.

[0063] As a refrigerant pipe connecting various devices constituting the refrigerant circuit 6, the outdoor unit 2 mainly includes an intake pipe 17, an exhaust pipe 18, a first gaseous refrigerant pipe 19, a liquid refrigerant pipe 20, and a second gaseous refrigerant pipe 21. The intake pipe 17 connects the four-way switching valve 10 to the intake side of the compressor 8. A liquid receiver 7 is installed in the intake pipe 17. The exhaust pipe 18 connects the exhaust side of the compressor 8 to the four-way switching valve 10. The first gaseous refrigerant pipe 19 connects the four-way switching valve 10 to the gas side of the outdoor heat exchanger 11. The liquid refrigerant pipe 20 connects the liquid side of the outdoor heat exchanger 11 to the liquid side shut-off valve 13. An outdoor expansion valve 12 is installed in the liquid refrigerant pipe 20. The second gaseous refrigerant pipe 21 connects the four-way switching valve 10 to the gas side shut-off valve 14.

[0064] The compressor 8 is a device that draws in low-pressure refrigerant from the refrigeration cycle through the suction pipe 17, compresses the refrigerant using a compression mechanism (not shown), and discharges the compressed refrigerant through the discharge pipe 18.

[0065] The four-way switching valve 10 is a mechanism that switches the state of the refrigerant circuit 6 between cooling and heating operation by switching the refrigerant flow direction. When the refrigerant circuit 6 is in cooling operation, the outdoor heat exchanger 11 functions as a refrigerant radiator or condenser, and the indoor heat exchanger 91 functions as a refrigerant evaporator. When the refrigerant circuit 6 is in heating operation, the outdoor heat exchanger 11 functions as a refrigerant evaporator, and the indoor heat exchanger 91 functions as a refrigerant condenser. When the four-way switching valve 10 switches the refrigerant circuit 6 to cooling operation, it connects the suction pipe 17 to the second gaseous refrigerant pipe 21 and the discharge pipe 18 to the first gaseous refrigerant pipe 19 (see reference). Figure 1 (The solid line inside the four-way switching valve 10). When the four-way switching valve 10 sets the refrigerant circuit 6 to heating operation, the four-way switching valve 10 connects the suction pipe 17 to the first gaseous refrigerant pipe 19 and the discharge pipe 18 to the second gaseous refrigerant pipe 21 (see reference). Figure 1 (The dashed line inside the four-way switching valve 10).

[0066] The outdoor heat exchanger 11 is a device that enables heat exchange between the refrigerant flowing inside and the air at the location where the outdoor unit 2 is installed. Details of the outdoor heat exchanger 11 will be described later.

[0067] An outdoor expansion valve 12 is disposed in the refrigerant circuit 6 between the outdoor heat exchanger 11 and the indoor heat exchanger 91. In this embodiment, the outdoor expansion valve 12 is disposed on the liquid refrigerant pipe 20 between the outdoor heat exchanger 11 and the liquid-side shut-off valve 13. The outdoor expansion valve 12 has a mechanism for regulating the pressure and flow rate of the refrigerant flowing in the liquid refrigerant pipe 20.

[0068] The receiver 7 is a container with a gas-liquid separation function that separates incoming refrigerant into gaseous and liquid refrigerant. Furthermore, the receiver 7 is a container with a function to store excess refrigerant generated according to changes in operating load, etc.

[0069] The liquid-side shut-off valve 13 is a valve located at the connection between the liquid refrigerant pipe 20 and the liquid refrigerant connecting pipe 4. The gas-side shut-off valve 14 is a valve located at the connection between the second gas refrigerant pipe 21 and the gas refrigerant connecting pipe 5. The liquid-side shut-off valve 13 and the gas-side shut-off valve 14 are open when the air conditioning unit 1 is in operation.

[0070] The outdoor fan 16 is a fan that draws in external hot air into the casing of the outdoor unit 2 (not shown) and supplies it to the outdoor heat exchanger 11, and exhausts the air that has exchanged heat with the refrigerant in the outdoor heat exchanger 11 to the outside of the casing of the outdoor unit 2. The outdoor fan 16 is, for example, a propeller fan.

[0071] (1-2) Indoor Units

[0072] Indoor unit 9 is a unit installed in the space to be conditioned. Indoor unit 9 can be, for example, a ceiling-recessed unit, but it can also be a ceiling-suspended, wall-mounted, or floor-standing unit. Furthermore, indoor unit 9 can also be installed outside the space to be conditioned. For example, indoor unit 9 can be installed in an attic, machine room, garage, etc. In this case, an air passage is provided to supply air that has undergone heat exchange with the refrigerant in indoor heat exchanger 91 from indoor unit 9 to the space to be conditioned. The air passage is, for example, a duct.

[0073] The indoor unit 9 mainly includes an indoor heat exchanger 91, an indoor expansion valve 93, and an indoor fan 92.

[0074] In the indoor heat exchanger 91, heat exchange occurs between the refrigerant flowing within the indoor heat exchanger 91 and the air in the air-conditioned space. The indoor heat exchanger 91 is, for example, a finned tube heat exchanger with multiple heat transfer tubes and fins (not shown). One end of the indoor heat exchanger 91 is connected to the indoor expansion valve 93 via a refrigerant piping. The other end of the indoor heat exchanger 91 is connected to the gaseous refrigerant connecting pipe 5 via a refrigerant piping.

[0075] An indoor expansion valve 93 is disposed in the refrigerant circuit 6 between the indoor heat exchanger 91 and the liquid refrigerant connecting pipe 4. The indoor expansion valve 93 has a mechanism for regulating the pressure and flow rate of the refrigerant passing through the indoor expansion valve 93.

[0076] The indoor fan 92 is configured to draw air from the target space into the housing (not shown) of the indoor unit 9 and supply it to the indoor heat exchanger 91, and then blow the air that has exchanged heat with the refrigerant in the indoor heat exchanger 91 out of the target space. The indoor fan 92 is, for example, a turbo fan.

[0077] (1-3) Control Department

[0078] The control unit 3 is a functional unit that controls the operation of various devices constituting the air conditioning unit 1.

[0079] The control unit 3 is configured to connect the outdoor control unit (not shown) of the outdoor unit 2 and the indoor control unit (not shown) of the indoor unit 9 via a transmission line (not shown) in a communicative manner. The outdoor control unit and the indoor control unit are, for example, units equipped with a microcomputer and a memory storing various programs for controlling the air conditioning unit 1 that can be implemented by the microcomputer. Furthermore, in Figure 1 For convenience, the control unit 3 is depicted in a position separate from the outdoor unit 2 and the indoor unit 9.

[0080] The control unit 3 is electrically connected to various devices in the outdoor unit 2 and indoor unit 9, including the compressor 8, four-way switching valve 10, outdoor expansion valve 12, outdoor fan 16, indoor fan 92, and indoor expansion valve 93. Furthermore, the control unit 3 is electrically connected to various sensors (not shown) installed in the outdoor unit 2 and indoor unit 9. The control unit 3 is also configured to communicate with a remote control (not shown) operated by the user of the air conditioning unit 1.

[0081] The control unit 3 controls the operation and stop of the air conditioning unit 1 and the operation of various devices constituting the air conditioning unit 1 based on measurement signals from various sensors and instructions received from a remote control (not shown).

[0082] (2) Structure of outdoor heat exchanger

[0083] The structure of the outdoor heat exchanger 11 is described with reference to the attached drawings.

[0084] Figure 2 This is a schematic three-dimensional view of the outdoor heat exchanger 11. Figure 3 This is a partial enlarged view of the heat exchange section 27 of the outdoor heat exchanger 11, which will be described later. Figure 4 This is a schematic diagram showing the installation state of the fins 29 (described later) in the heat exchange section 27 relative to the flat tube 28. Figure 5 This is a schematic diagram of the outdoor heat exchanger 11. Figure 5 The arrows in the heat exchange section 27 indicate the flow of refrigerant during heating operation (when the outdoor heat exchanger 11 functions as an evaporator for the refrigerant).

[0085] Additionally, in the following descriptions, terms such as "up," "down," "left," "right," "front," and "back" are sometimes used to indicate orientation and location. Unless otherwise stated, these terms follow... Figure 2 The direction of the arrows depicted. In addition, these expressions of direction and position are used for ease of explanation, and unless otherwise specified, the orientation and position of the outdoor heat exchanger 11 as a whole or of each structure of the outdoor heat exchanger 11 are not specifically defined as the orientation and position of the expressions described.

[0086] The outdoor heat exchanger 11 is a device that enables heat exchange between the refrigerant flowing inside and the air.

[0087] The outdoor heat exchanger 11 mainly comprises multiple flat tubes 28, multiple fins 29, a return manifold 30, and an inlet / outlet manifold 40. In this embodiment, the flat tubes 28, fins 29, return manifold 30, and inlet / outlet manifold 40 are all made of aluminum or aluminum alloy.

[0088] The flat tube 28 and the fins 29 fixed to the flat tube 28 form a heat exchange section 27. In the outdoor heat exchanger 11, air flows in the ventilation path formed by the flat tube 28 and the fins 29 of the heat exchange section 27, thereby exchanging heat between the refrigerant flowing in the flat tube 28 and the air flowing in the ventilation path.

[0089] (2-1) Flat tube

[0090] Flat tube 28 is as follows Figure 3 The diagram shows a flat heat transfer tube with flat surfaces 28a at the top and bottom that serve as heat transfer surfaces. (Example:) Figure 3 As shown, a plurality of refrigerant passages 28b for refrigerant flow are formed in the flat tube 28. For example, the flat tube 28 is a flat porous tube with a small cross-sectional area of ​​refrigerant passages 28b for refrigerant flow. In this embodiment, these plurality of refrigerant passages 28b are arranged in the airflow direction.

[0091] In the outdoor heat exchanger 11, such as Figure 5 As shown, multiple layers of flat tubes 28 extending horizontally between the side of the return manifold 30 and the side of the inlet / outlet manifold 40 are arranged vertically. Furthermore, in this embodiment, the flat tubes 28 extending between the side of the return manifold 30 and the side of the inlet / outlet manifold 40 are bent at one point, and the heat exchange section 27 formed by the flat tubes 28 is roughly L-shaped when viewed from above. In this embodiment, the multiple flat tubes 28 are arranged at fixed vertical intervals.

[0092] (2-2) Fins

[0093] Multiple fins 29 are components used to increase the heat transfer area of ​​the outdoor heat exchanger 11. Each fin 29 is a plate-shaped component extending along the layer direction of the flat tubes 28. The outdoor heat exchanger 11 is used in a manner in which multiple flat tubes 28 extending horizontally are arranged in a vertical direction. Therefore, when the outdoor heat exchanger 11 is installed in the outdoor unit 2, each fin 29 extends in the vertical direction.

[0094] like Figure 4As shown, each fin 29 has multiple notches 29a extending along the insertion direction of the flat tube 28 for inserting multiple flat tubes 28. The notches 29a extend along the extension direction of the fin 29 and in a direction orthogonal to the thickness direction of the fin 29. When the outdoor heat exchanger 11 is installed in the outdoor unit 2, the notches 29a formed in each fin 29 extend horizontally. The notches 29a are formed in the fin 29 at intervals corresponding to the arrangement intervals of the flat tubes 28. In the outdoor heat exchanger 11, multiple fins 29 are arranged along the extension direction of the flat tubes 28. By inserting the flat tubes 28 into the multiple notches 29a of the multiple fins 29, multiple ventilation paths for airflow are divided between adjacent flat tubes 28.

[0095] Each fin 29 has a connecting portion 29b that communicates vertically on the upstream or downstream side of the flat tube 28 in the airflow direction. In this embodiment, the connecting portion 29b of the fin 29 is located on the upwind side relative to the flat tube 28.

[0096] (2-3) Inlet and outlet manifolds

[0097] The inlet / outlet manifold 40 has a gas manifold 50 at the top and a liquid manifold 60 at the bottom. The gas manifold 50 and the liquid manifold 60 are separated vertically by a partition plate 41. The gas manifold 50 has an internal space, and the liquid manifold 60 has a space separated from the internal space of the gas manifold 50 by means of the partition plate 41. In addition, the upper end of the gas manifold 50 is closed by a cover 42. The partition plate 41 also functions as the base plate of the gas manifold 50.

[0098] A gas refrigerant connection pipe 19a, constituting one end of the first gas refrigerant pipe 19, is connected to the gas manifold 50. The gas refrigerant connection pipe 19a may be made of an alloy such as an aluminum alloy without a cladding containing solder.

[0099] The liquid manifold 60 is connected to a liquid refrigerant connection pipe 20a that forms one end of the liquid refrigerant pipe 20.

[0100] like Figure 5 As shown, one end of each flat tube 28 is connected to the return manifold 30, and the other end of each flat tube 28 is connected to the gas manifold 50 and liquid manifold 60 of the inlet / outlet manifold 40. The outdoor heat exchanger 11 is arranged in the outer casing (not shown) of the outdoor unit 2 in such a manner that the length direction of the return manifold 30 and the inlet / outlet manifold 40 is substantially aligned with the vertical direction.

[0101] (2-4) Turnback manifold

[0102] The flat tubes 28 connected to the return manifold 30 are at ends that are different from the ends of the flat tubes 28 connected to the gas manifold 50 and liquid manifold 60 of the inlet and outlet manifold 40.

[0103] (3) Flow of refrigerant in outdoor heat exchanger

[0104] When the air conditioning unit 1 is in heating operation and the outdoor heat exchanger 11 functions as an evaporator for the refrigerant, the refrigerant in a liquid state or a gas-liquid two-phase state, flowing from the liquid refrigerant pipe 20 to the liquid manifold 60, is split within the internal space of the liquid manifold 60 and flows in the flat pipes 28 connected to the liquid manifold 60. The refrigerant flowing in each flat pipe 28 partially evaporates through heat exchange with air and reaches the lower region of the internal space of the return manifold 30. The refrigerant sent to the lower region of the internal space of the return manifold 30 is then sent to the upper region of the internal space of the return manifold 30. The refrigerant reaching the upper region of the return manifold 30 flows in the flat pipes 28 connected to the upper region of the return manifold 30. The refrigerant flowing in each flat pipe 28 further evaporates through heat exchange with air again and reaches the gas manifold 50. The refrigerant reaching the gas manifold 50 merges and flows in the first gas refrigerant pipe 19.

[0105] When the air conditioning unit 1 is in cooling or defrosting operation, the refrigerant flows in the refrigerant circuit 6 in the opposite direction to that during heating operation. Specifically, the refrigerant discharged from the compressor 8 flows into the gas manifold 50 after passing through the first gas refrigerant pipe 19. The gaseous refrigerant reaching the gas manifold 50 is split within the internal space of the gas manifold 50 and flows in the flat pipes 28 connected to the gas manifold 50. The refrigerant flowing in each flat pipe 28 dissipates heat or condenses through heat exchange with the air and reaches the upper region of the internal space of the return manifold 30. The refrigerant delivered to the upper region of the internal space of the return manifold 30 descends within the internal space of the return manifold 30 and reaches the lower region of the internal space of the return manifold 30. The refrigerant reaching the lower region of the return manifold 30 flows in the flat pipes 28 connected to the lower region of the return manifold 30. The refrigerant flowing in each flat pipe 28 further dissipates heat or condenses through heat exchange with the air again and reaches the liquid manifold 60. The refrigerant that reaches the liquid manifold 60 flows in the liquid refrigerant pipe 20 after merging.

[0106] (4) Detailed information on the gas manifold

[0107] Figure 6 A perspective view of the gas manifold 50 is shown. Figure 7 An exploded perspective view of the gas manifold 50 is shown.

[0108] The gas manifold 50 has a first manifold component 51, a second manifold component 52, a third manifold component 53, and a fourth manifold component 54. The gas manifold 50 is formed by brazing the first manifold component 51, the second manifold component 52, the third manifold component 53, and the fourth manifold component 54 together.

[0109] (4-1) First manifold component

[0110] The first manifold component 51 is a component stacked in such a way that it engages with the right side of the second manifold component 52. The front-to-back length of the first manifold component 51 is the same as the front-to-back length of the second manifold component 52 and the third manifold component 53, and the same as the front-to-back length of the portion of the flat pipe connecting plate 54a of the fourth manifold component 54, excluding the two side faces 54b.

[0111] The first manifold component 51 is a component made of metal such as aluminum alloy that does not have a cladding containing brazing filler metal.

[0112] The first manifold component 51 has a first plate-shaped portion 51a and a semi-circular portion 51b.

[0113] The first plate-shaped portion 51a is a plate-shaped portion that extends along the vertical direction and the front-back direction on the front and rear sides of the semi-circular portion 51b, respectively.

[0114] The semi-circular portion 51b is configured to connect the front and rear portions of the first plate-shaped portion 51a, and is a semi-circular arc-shaped portion formed by half of an arc with the length direction of the gas manifold 50 as the axial direction. The semi-circular portion 51b bulges out toward the side opposite to the second manifold member 52 relative to the first plate-shaped portion 51a. A connection opening 51x is provided in the semi-circular portion 51b to connect to the gas refrigerant connection pipe 19a of the first gas refrigerant pipe 19. The connection opening 51x is an opening that penetrates the semi-circular portion 51b in the plate thickness direction.

[0115] In addition, the front portion and the rear portion of the first plate-shaped portion 51a of the first manifold component 51 respectively contact the claw portion 54c of the fourth manifold component 54, which will be described later, and are pressed from the right side by the claw portion 54c of the fourth manifold component 54.

[0116] In addition, the partition plate 41 and the upper cover 42 are disposed between the first manifold component 51 and the second manifold component 52, and function as the lower cover and upper cover for forming the internal space of the gas manifold 50.

[0117] (4-2) Second manifold assembly

[0118] The second manifold component 52 is a component stacked such that it faces and contacts the right side of the third manifold component 53 and faces and contacts the left side of the first plate-shaped portion 51a of the first manifold component 51. The front-to-back length of the second manifold component 52 is the same as that of the third manifold component 53. The second manifold component 52 is not particularly limited, but it is preferable to have a cladding with solder formed on its surface.

[0119] The second manifold component 52 has a second plate-shaped portion 52a and a plurality of openings 52x.

[0120] The second plate-shaped portion 52a has a flat plate shape that extends in the vertical and horizontal directions and the front-back direction.

[0121] Multiple openings 52x are arranged in the vertical direction and are through openings that extend through the thickness direction of the second plate-shaped portion 52a.

[0122] When viewed from the thickness direction of the second manifold component 52, the front and rear edges of each opening 52x are located further inward than the opening 53x of the third manifold component 53, and further inward than each flat pipe connection opening 54x formed on the flat pipe connection plate 54a of the fourth manifold component 54. The width of the plurality of openings 52x in the front-rear direction of the second manifold component 52 is narrower than the width of the flat pipe 28 in the front-rear direction. In addition, when viewed from the thickness direction of the second manifold component 52, the upper and lower edges of the plurality of openings 52x of the second manifold component 52 are located further outward than each flat pipe connection opening 54x formed on the flat pipe connection plate 54a of the fourth manifold component 54.

[0123] Therefore, the ends of each flat tube 28 inserted into the gas manifold 50 can be brought into contact with the edges of each opening 52x of the second manifold component 52, thus the degree of insertion of the flat tube 28 into the gas manifold 50 can be determined.

[0124] In addition, in this embodiment, the second manifold component 52 also functions as a component constituting the interior of the liquid manifold 60.

[0125] (4-3) Third manifold component

[0126] The third manifold component 53 is a component stacked such that it faces and contacts the right side of the flat tube connecting plate 54a of the fourth manifold component 54, and faces and contacts the left side of the second manifold component 52. The length of the third manifold component 53 in the front-rear direction is the same as the length of the portion of the flat tube connecting plate 54a of the fourth manifold component 54 in the front-rear direction, excluding the two side faces 54b. The third manifold component 53 is not particularly limited, but it is preferable to have a cladding with solder formed on its surface.

[0127] The third manifold component 53 has a third plate-shaped portion 53a and multiple openings 53x.

[0128] The third plate-shaped portion 53a has a flat plate shape that extends in both the vertical and front-back directions.

[0129] Multiple openings 53x are arranged in the vertical direction and are openings that penetrate through the thickness direction of the third plate-shaped portion 53a.

[0130] Each opening 53x of the third manifold component 53 is larger than each flat tube connection opening 54x formed on the flat tube connection plate 54a of the fourth manifold component 54. With the third manifold component 53 stacked on the flat tube connection plate 54a of the fourth manifold component 54, when viewed from the thickness direction of the third manifold component 53, the outer edge of each opening 53x of the third manifold component 53 is positioned outside the outer edge of each flat tube connection opening 54x formed on the flat tube connection plate 54a of the fourth manifold component 54. This allows for the provision of an escape point for molten brazing filler metal during brazing, thus preventing the molten filler metal from moving due to capillary action and blocking the refrigerant passage 28b of the flat tube 28.

[0131] In addition, in this embodiment, the third manifold component 53 also functions as a component constituting the interior of the liquid manifold 60.

[0132] (4-4) Fourth manifold component

[0133] The fourth manifold component 54 is a peripheral component that, together with the first manifold component 51, forms the outer shape of the gas manifold 50. The fourth manifold component 54 may also have a cladding with solder formed on its surface.

[0134] The fourth manifold component 54 has a flat pipe connecting plate 54a, a side portion 54b, and a claw portion 54c.

[0135] Although not particularly limited, the fourth manifold component 54 of this embodiment can be formed by bending a rolled metal sheet with a crease along the length of the gas manifold 50.

[0136] The flat tube connecting plate 54a is a flat plate-shaped portion that extends in both the vertical and horizontal directions. Multiple flat tube connecting openings 54x are formed on the flat tube connecting plate 54a, arranged vertically. Each flat tube connecting opening 54x is a through opening in the thickness direction of the flat tube connecting plate 54a. With the flat tube 28 inserted into the flat tube connecting opening 54x with one end completely passing through, the flat tube 28 is brazed together. In the brazed state, the entire inner circumferential surface of the flat tube connecting opening 54x is in contact with the entire outer circumferential surface of the flat tube 28. Furthermore, each opening 53x of the third manifold component 53 is larger than the flat tube 28, so no friction occurs between the flat tube 28 and each opening 53x of the third manifold component 53 when inserting the flat tube 28 into the flat tube connecting opening 54x, thus facilitating the insertion operation.

[0137] The side portion 54b has: a surface extending to the right and expanding vertically on the front side of the flat tube connecting plate 54a; and a surface extending to the right and expanding vertically on the rear side of the flat tube connecting plate 54a.

[0138] The claw portion 54c has a portion extending from the right end of the front side portion 54b toward the rear and a portion extending from the right end of the rear side portion 54b toward the front.

[0139] In a top-view configuration, before the first plate-shaped portions 51a of the third manifold component 53, the second manifold component 52, and the first manifold component 51 are positioned inside the fourth manifold component 54, the claw portions 54c extend along the extension lines of the side portions 54b. With the first plate-shaped portions 51a of the third manifold component 53, the second manifold component 52, and the first manifold component 51 positioned inside the fourth manifold component 54, the claw portions 54c are bent, thereby pressing the third manifold component 53, the second manifold component 52, and the first manifold component 51 tightly against the fourth manifold component 54. Furthermore, in this configuration, the components are completely fixed by brazing in a furnace.

[0140] In addition, in this embodiment, the fourth manifold component 54 also functions as a component constituting the outer periphery of the liquid manifold 60.

[0141] (5) Connection of gas manifold to gas refrigerant piping

[0142] The connection between the gas manifold 50 and the gas refrigerant connection piping 19a based on furnace brazing will be described below.

[0143] Figure 8 A perspective view of the connection between the gas manifold 50 and the gas refrigerant connection pipe 19a is shown. Figure 9An exploded perspective view is shown of the vicinity of the connection between the gas manifold 50 and the gas refrigerant connection pipe 19a. Figure 10 This is a perspective view showing the case where the first connecting part 56 is fixed to the gas refrigerant connection pipe 19a.

[0144] The gas manifold 50 is connected and fixed to the gas refrigerant connection pipe 19a via the connection part 58.

[0145] The gas refrigerant connection pipe 19a has a pipe connection portion 19x near its end on the side connected to the gas manifold 50. This pipe connection portion 19x is formed by extending linearly along the axial direction in a cylindrical shape. Additionally, the first gas refrigerant pipe 19 has a cylindrical shape formed by bending it at multiple locations. In this embodiment, the gas refrigerant connection pipe 19a also has bent portions. The gas refrigerant connection pipe 19a and the first gas refrigerant pipe 19 containing it have a predetermined thickness to ensure pressure resistance against the pressure of the gas refrigerant flowing inside. In this embodiment, the gas refrigerant connection pipe 19a and the first gas refrigerant pipe 19 containing it do not have a cladding containing solder, but are made of a metal such as an aluminum alloy with a predetermined composition.

[0146] The connecting end of the pipe connection portion 19x of the gas refrigerant connection pipe 19a has a pipe opening 19y with a shape formed by cutting a portion of the cylindrical end. Specifically, when viewed from the length direction of the gas manifold 50, the pipe opening 19y of the pipe connection portion 19x has the following shape: a portion of the cylindrical end is cut along the edge of the connecting opening 51x of the first manifold member 51 of the gas manifold 50 on the side near the internal space of the gas manifold 50.

[0147] A pipe fixing hole 19z is provided in the pipe connection portion 19x. The pipe fixing hole 19z is a threaded hole that extends through the thickness direction. A threaded groove is provided on the inner circumference of the pipe fixing hole 19z.

[0148] The connecting part 58 has a first connecting part 56 and a second connecting part 57.

[0149] The first connecting part 56 has a cylindrical component 56a and a first screw 56s.

[0150] The cylindrical component 56a has a cylindrical body, an insertion-side opening 56x, a connection-side opening 56y, a first connection hole 56z, and a notch 56b. The thickness of the cylindrical component 56a is thinner than the thickness of the gas refrigerant connection pipe 19a and the first gas refrigerant pipe 19 containing the gas refrigerant connection pipe 19a. The cylindrical component 56a includes a metal layer such as aluminum alloy and a cladding containing brazing filler metal. The cladding may be provided, for example, on the inner circumference of the cylindrical component 56a, or at a position in the connection portion 58 corresponding to the contact portion between the gas manifold 50 and the first connection portion 56.

[0151] With the pipe connection portion 19x inserted inside, the cylindrical member 56a is screwed to the pipe connection portion 19x by a first screw 56s, thereby determining the relative position of the first connection portion 56 and the pipe connection portion 19x. Specifically, with the pipe connection portion 19x inserted inside the cylindrical member 56a such that the first connection hole 56z in the cylindrical member 56a communicates with the pipe fixing hole 19z in the pipe connection portion 19x, the first screw 56s is inserted into both the first connection hole 56z and the pipe fixing hole 19z, thereby fixing the first connection portion 56 to the pipe connection portion 19x. Thus, with the first connection portion 56 fixed to the pipe connection portion 19x, the cylindrical member 56a, which has a cladding containing brazing filler metal, covers the pipe connection portion 19x from the axial direction. Therefore, during brazing in the furnace, the molten brazing filler metal can be readily and adequately supplied to the joint between the piping connection 19x and the gas manifold 50.

[0152] The connecting-side opening 56y of the cylindrical member 56a is shaped as a semi-circular arc along the first manifold member 51. Specifically, the connecting-side opening 56y of the cylindrical member 56a has a shape such that, when viewed from the length direction of the gas manifold 50, a portion of the cylindrical end is cut along the edge of the connecting opening 51x of the first manifold member 51 of the gas manifold 50 on the side closest to the interior space of the gas manifold 50. Thus, when viewed from the length direction of the gas manifold 50, the inner circumferential surface of the first manifold member 51 of the gas manifold 50, the connecting-side opening 56y of the cylindrical member 56a, and the piping connection portion 19x are arranged to overlap each other.

[0153] The insertion side opening 56x of the cylindrical member 56a is an opening that opens axially in the cylindrical member 56a to allow the piping connection portion 19x to be inserted.

[0154] The notch 56b of the cylindrical member 56a is a notch that is partially provided only around the insertion-side opening 56x when viewed axially from the direction extending from the pipe connection portion 19x when the member is installed in the pipe connection portion 19x. Specifically, the notch 56b is not provided throughout the entire circumference of the cylindrical member 56a; the cylindrical member 56a has an uncut portion around the notch 56b. The notch 56b has a shape that opens on the insertion-side opening 56x side of the cylindrical member 56a. Specifically, the notch 56b has a shape in which a portion of the edge of the cylindrical member 56a on the insertion-side opening 56x side is recessed axially toward the cylindrical member 56a.

[0155] like Figure 1 As shown, the gas refrigerant connection pipe 19a, with the first connecting portion 56 fixed thereon, is connected to the connection opening 51x of the first manifold component 51 provided in the gas manifold 50. The connection opening 51x of the first manifold component 51 has a shape obtained by cutting from the apex of the semicircular portion 51b (viewed along the length of the gas manifold 50) toward the center of the semicircular portion 51b using a cylindrical cutting tool in a direction orthogonal to the length of the gas manifold 50. Specifically, when viewed from the axial direction of the pipe connection portion 19x, both the outer edge of the connection opening 51x of the first manifold component 51 and the outer edge of the cylindrical component 56a are circular. Therefore, if only the gas refrigerant connection pipe 19a with the first connecting portion 56 fixed thereon is connected to the connection opening 51x of the first manifold component 51, the first connecting portion 56 and the gas refrigerant connection pipe 19a are in a state where they can rotate about the axial direction of the pipe connection portion 19x. In contrast, the second connecting portion 57, described below, restricts movement by preventing the first connecting portion 56 and the gas refrigerant connecting pipe 19a from rotating. Furthermore, if only the gas refrigerant connecting pipe 19a, to which the first connecting portion 56 is fixed, is connected to the connection opening 51x of the first manifold component 51, the first connecting portion 56 and the gas refrigerant connecting pipe 19a will detach along the direction in which the pipe connecting portion 19x extends, i.e., along the axial direction of the pipe connecting portion 19x, in the direction of separation from the first manifold component 51. In contrast, the second connecting portion 57, described below, restricts movement by preventing the first connecting portion 56 and the gas refrigerant connecting pipe 19a from detaching.

[0156] The second connecting part 57 has a connecting piece 57a and a second screw 57s. The connecting piece 57a is fixed to the first manifold component 51 of the gas manifold 50 by the second screw 57s.

[0157] The connecting piece 57a has an insertion portion 57b, a connecting portion 57c, and a manifold fixing portion 57d. The thickness of the connecting piece 57a is thinner than the thickness of the gas refrigerant connection pipe 19a and the first gas refrigerant pipe 19 containing the gas refrigerant connection pipe 19a. The connecting piece 57a includes a metal layer such as aluminum alloy and a cladding containing brazing filler metal. The cladding is provided, for example, on the side of the connecting piece 57a facing the first manifold member 51. In this embodiment, the connecting piece 57a has a shape obtained by bending a plate-shaped member in two places.

[0158] The manifold fixing portion 57d is provided with a second connecting hole 57z that extends through the thickness direction of the manifold fixing portion 57d. Here, in the first manifold component 51 of the gas manifold 50 described above, near the connecting opening 51x, a manifold fixing hole 51z is provided at the apex of the semi-circular portion 51b, which extends through the thickness direction of the first manifold component 51. Thus, with the second connecting hole 57z of the manifold fixing portion 57d communicating with the manifold fixing hole 51z of the first manifold component 51, the second connecting portion 57 is fixed to the first manifold component 51 of the gas manifold 50 by inserting a second screw 57s into the second connecting hole 57z and the manifold fixing hole 51z.

[0159] The connecting part 57c extends from the end of the manifold fixing part 57d on the side of the cylindrical member 56a in a direction separate from the first manifold member 51 of the gas manifold 50, connecting the manifold fixing part 57d with the insertion part 57b. Furthermore, in this embodiment, the head of the first screw 56s is located between the connecting part 57c and the cylindrical member 56a.

[0160] The insertion portion 57b extends radially along the pipe connection portion 19x from the portion of the connecting portion 57c furthest from the first manifold member 51 toward the axis of the pipe connection portion 19x. When viewed axially from the pipe connection portion 19x, the insertion portion 57b extends to the position where the end of the insertion portion 57b opposite to the side of the connecting portion 57c overlaps with the notch portion 56b of the cylindrical member 56a. Therefore, the insertion portion 57b contacts the edge of the end of the insertion portion 57b opposite to the side of the connecting portion 57c in such a way that the edge of the notch portion 56b mates with the edge of the notch portion 56b. More specifically, the surface of the insertion portion 57b near the end opposite to the side of the connecting portion 57c, facing the first manifold member 51 of the gas manifold 50, contacts the portion of the edge of the notch portion 56b of the cylindrical member 56a that extends circumferentially along the cylindrical member 56a in such a way that they mate with each other. Furthermore, the connecting piece 57a, having the insertion portion 57b, is screwed to the first manifold member 51 of the gas manifold 50 at the manifold fixing portion 57d by a second screw 57s. As a result, the surface of the insertion portion 57b near its insertion-direction end, on the gas manifold 50 side, presses a portion of the edge of the notch portion 56b of the cylindrical member 56a toward the gas manifold 50 side. This restricts the movement of the cylindrical member 56a along the axial direction of the pipe connection portion 19x toward the direction separating from the first manifold member 51, and also restricts the movement of the pipe connection portion 19x, which is integrated with the cylindrical member 56a, toward the direction separating from the first manifold member 51. Moreover, the end portion of the insertion portion 57b on the side opposite to the connecting portion 57c has an arc shape in the insertion direction relative to the notch portion 56b. This arc-shaped portion of the insertion portion 57b contacts the circumferential surface of the pipe connection portion 19x. Furthermore, the end of the insertion portion 57b opposite to the side of the connecting portion 57c contacts the two circumferential edges of the cylindrical member 56a in the notch 56b of the cylindrical member 56a. More specifically, the front edge near the end of the insertion portion 57b opposite to the side of the connecting portion 57c contacts the front edge of the notch 56b of the cylindrical member 56a, and the rear edge of the end of the insertion portion 57b opposite to the side of the connecting portion 57c contacts the rear edge of the notch 56b of the cylindrical member 56a. Furthermore, the connecting piece 57a having the insertion portion 57b is screwed to the first manifold member 51 of the gas manifold 50 at the manifold fixing portion 57d by a second screw 57s. As a result, the rotation of the cylindrical component 56a about the axial direction of the pipe connection portion 19x is restricted, and the rotation of the pipe connection portion 19x, which is integrated with the cylindrical component 56a, about the axial direction of the pipe connection portion 19x is also restricted.

[0161] (6) Furnace brazing of gas manifold and gas refrigerant connection piping

[0162] With the gas manifold 50 and the gas refrigerant connecting pipe 19a temporarily fixed in position via the connecting part 58, the gas manifold 50, the gas refrigerant connecting pipe 19a, and the connecting part 58 are placed in the furnace, whereby the brazing filler metal contained in the connecting part 58 melts and is brazed together.

[0163] When brazing in a furnace, firstly, as... Figure 10 As shown, the first connecting part 56 in the connecting part 58 is fixed to the gas refrigerant connecting pipe 19a. Specifically, the pipe connecting part 19x is inserted into the cylindrical member 56a, and the pipe connecting part 19x is screwed to the cylindrical member 56a by the first screw 56s.

[0164] Next, the integrated component of the piping connection portion 19x and the cylindrical member 56a is inserted into the connection opening 51x of the first manifold member 51 of the gas manifold 50. In this state, the integrated component of the piping connection portion 19x and the cylindrical member 56a is allowed to move along the axial direction of the piping connection portion 19x toward the direction of separation from the first manifold member 51, and the integrated component of the piping connection portion 19x and the cylindrical member 56a is also allowed to rotate about the axial direction of the piping connection portion 19x.

[0165] In this condition, the movement and rotation of the integrated pipe connection portion 19x and the cylindrical member 56a are restricted by using the second connection portion 57 in the connection portion 58. Specifically, with the insertion portion 57b of the connecting piece 57a of the second connection portion 57 inserted into the notch portion 56b of the cylindrical member 56a, the manifold fixing portion 57d is screwed and fixed to the first manifold member 51 of the gas manifold 50 using the second screw 57s. Thus, the connecting piece 57a fixed to the first manifold member 51 of the gas manifold 50 restricts the axial movement and rotation of the cylindrical member 56a.

[0166] By temporarily fixing the gas manifold 50 and the gas refrigerant connection pipe 19a in a state where the positional relationship has been determined as described above, the gas manifold 50, the gas refrigerant connection pipe 19a, and the connection part 58 are placed in the furnace for brazing.

[0167] (7) Features of the implementation method

[0168] In the outdoor heat exchanger 11 of this embodiment, when the gas manifold 50 is connected to the gas refrigerant connection pipe 19a, the gas refrigerant connection pipe 19a is placed in the furnace with its position relative to the gas manifold 50 and its orientation restricted by the connecting part 58, thereby the gas manifold 50 and the gas refrigerant connection pipe 19a are brazed in the furnace. This allows for proper connection between the gas refrigerant connection pipe 19a and the gas manifold 50.

[0169] Furthermore, the furnace brazing is performed in the following state: the insertion portion 57b of the second connection portion 57 fixed to the gas manifold 50 is pressed into the notch portion 56b of the cylindrical member 56a fixed to the first connection portion 56 of the gas refrigerant connection pipe 19a from the side opposite to the gas manifold 50. Thus, during furnace brazing, the gas refrigerant connection pipe 19a is prevented from detaching from the gas manifold 50.

[0170] Furthermore, the brazing in the furnace is performed in the following state: the insertion portion 57b of the second connecting portion 57 fixed to the gas manifold 50 contacts the two circumferential edges of the notch portion 56b of the cylindrical component 56a of the first connecting portion 56 fixed to the gas refrigerant connecting pipe 19a. This prevents the gas refrigerant connecting pipe 19a from rotating relative to the gas manifold 50 about its axis.

[0171] Furthermore, since furnace brazing is performed with the cylindrical component 56a covering the piping connection portion 19x from all sides, the molten brazing filler metal can be easily and adequately supplied to the joint between the piping connection portion 19x and the gas manifold 50 during furnace brazing.

[0172] The first manifold component 51 of the gas manifold 50 has a semi-circular portion 51b. Therefore, even when supplied with high-pressure gaseous refrigerant, pressure resistance is easily ensured. Furthermore, the thickness of the first manifold component 51 is, for example, greater than the thickness of the cylindrical component 56a, which also easily ensures pressure resistance. Thus, the first manifold component 51 with a predetermined thickness is not formed by bending a plate-shaped component, but can be obtained by extrusion molding. Furthermore, when the first manifold component 51 is formed by extrusion molding, from the viewpoint of minimizing dimensional errors, it is preferable not to have a cladding containing solder. Thus, even if the first manifold component 51 of the gas manifold 50 does not contain solder, in this embodiment, since the cylindrical component 56a has a cladding containing solder, in-furnace brazing is possible.

[0173] Similarly, even if the gas refrigerant connection piping 19a of the first gas refrigerant pipe 19 does not have a cladding containing brazing filler metal, in-furnace brazing is still possible because the cylindrical component 56a has a cladding containing brazing filler metal.

[0174] (8) Other implementation methods

[0175] (8-1) Other implementation methods A

[0176] In the above embodiments, the following example is illustrated: the position of the gas refrigerant connection pipe 19a relative to the gas manifold 50 is determined by inserting the insertion portion 57b of the connecting piece 57a into the notch portion 56b of the cylindrical member 56a.

[0177] In contrast, such as Figure 11 , Figure 12 , Figure 13 As shown, it can also be constructed as follows: a slit 156b is provided in the cylindrical member 56a to replace the notch 56b in the above embodiment, and a recess 19t is provided on the outer peripheral surface of the pipe connection portion 19x for inserting the end of the insertion portion 57b of the connecting piece 57a. Specifically, as Figure 13 As shown, the recess 19t is formed in the pipe connection portion 19x by recessing from the outer periphery of the pipe connection portion 19x toward the radially inward side. It should be noted that the recess 19t is not a structure that allows the pipe connection portion 19x to extend radially through; the degree of recess is converging within the range of the wall thickness. Furthermore, in this configuration, the first screw 56s, the first connection hole 56z, and the pipe fixing hole 19z of the above embodiment are not required.

[0178] In this configuration, the insertion portion 57b of the connecting piece 57a fixed to the gas manifold 50 is inserted into the gap 156b of the cylindrical member 56a, and then embedded into the recess 19t provided on the outer peripheral surface of the pipe connection portion 19x.

[0179] Therefore, the edge of the end opposite to the connecting portion 57c in the insertion portion 57b of the connecting piece 57a, that is, the edges at both ends of the pipe connection portion 19x in the circumferential direction, contacts the edges at both ends of the recess 19t in the circumferential direction of the pipe connection portion 19x, thereby restricting the rotation of the pipe connection portion 19x. Furthermore, the edge of the end opposite to the connecting portion 57c in the insertion portion 57b of the connecting piece 57a, that is, the edges at both ends of the pipe connection portion 19x in the circumferential direction, contacts the edges at both ends of the circumferential direction of the slot 156b of the cylindrical member 56a, thereby also restricting the rotation of the cylindrical member 56a.

[0180] Furthermore, the axial surfaces of the pipe connection portion 19x near the end of the insertion portion 57b of the connecting piece 57a opposite to the side of the connecting portion 57c contact the axial surfaces of the recess 19t of the pipe connection portion 19x, thereby restricting axial movement of the pipe connection portion 19x and preventing it from falling off. Also, the axial surfaces of the insertion portion 57b of the connecting piece 57a near the end of the insertion portion 57b opposite to the side of the connecting portion 57c contact the axial surfaces of the slot 156b of the cylindrical member 56a, thereby restricting axial movement of the cylindrical member 56a and preventing it from falling off.

[0181] Therefore, during brazing in the furnace, the molten brazing filler metal of the cylindrical component 56a can be adequately supplied to the joint between the gas manifold 50 and the gas refrigerant connection pipe 19a.

[0182] (8-2) Other implementation methods B

[0183] In the above embodiments, the following example is illustrated: the position of the gas refrigerant connection pipe 19a relative to the gas manifold 50 is determined by inserting the insertion portion 57b of the connecting piece 57a into the notch portion 56b of the cylindrical member 56a.

[0184] In contrast, such as Figure 14 , Figure 15 As shown, the configuration can also be as follows: Instead of the second connecting portion 57 in the above embodiment, a fixing plate 256a is provided on the cylindrical member 56a. This fixing plate 256a is formed by cutting a portion of the side surface of the cylindrical member 56a and laying it down towards the first manifold member 51. The fixing plate 256a extends outward from the cylindrical member 56a in a circumferential direction and is a plate-shaped portion that extends in a planar manner with the axial direction of the cylindrical member 56a as the normal direction. In addition, the fixing plate 256a is integral with the cylindrical member 56a. Furthermore, in this configuration, the notch portion 56b provided in the cylindrical member 56a in the above embodiment is not required.

[0185] Furthermore, in this construction, instead of the pipe fixing hole 19z, the first connecting hole 56z, and the first screw 56s in the above embodiment, a pipe fixing hole 119z is provided ( Figure 15 (Represented by dashed lines in the middle), third connecting hole 156z ( Figure 15 (Indicated by dashed lines) and third screw 156s. Specifically, when viewed axially from the pipe connection portion 19x, a third connection hole 156z is provided on the side of the cylindrical member 56a that extends in the opposite direction to the fixing plate 256a. The third connection hole 156z is a hole that radially penetrates the cylindrical member 56a toward the pipe connection portion 19x. Furthermore, a pipe fixing hole 119z is provided in the pipe connection portion 19x at a position corresponding to the third connection hole 156z. The pipe fixing hole 119z is formed by recessing from the outer periphery of the pipe connection portion 19x toward the radially inward side. It should be noted that the pipe fixing hole 119z is not a structure that allows the pipe connection portion 19x to penetrate radially; the degree of recess is limited to the range of the wall thickness. Furthermore, the third connecting hole 156z and the pipe fixing hole 119z are screwed together by the third screw 156s with the pipe connecting portion 19x overlapping radially. Thus, the cylindrical component 56a is fixed to the pipe connecting portion 19x.

[0186] The fixing plate 256a is obtained, for example, by cutting a cylindrical component along its circumference at two cutting lines extending axially along the cylindrical shape and pressing it radially outward from the cylindrical shape. A fourth connecting hole 256z extending through the plate thickness direction is provided in the fixing plate 256a. Figure 14 (Represented by dashed lines). With the fourth connecting hole 256z of the fixing plate 256a overlapping with the manifold fixing hole 51z of the first manifold component 51 of the gas manifold 50, the fourth screw 256s is used for screwing, thereby fixing the cylindrical component 56a and the first manifold component 51 of the gas manifold 50.

[0187] Therefore, the movement of the fixing plate 256a of the cylindrical component 56a in the direction of separation from the first manifold component 51 is restricted, thereby restricting the detachment of the pipe connection portion 19x fixed to the cylindrical component 56a by the third screw 156s. Furthermore, by restricting the rotation of the fixing plate 256a about the axial direction of the cylindrical component 56a, the rotation of the pipe connection portion 19x fixed to the cylindrical component 56a by the third screw 156s is also restricted.

[0188] (8-3) Other implementation methods C

[0189] In the above embodiment, the following situation is illustrated: in the state where the front and rear edges of the end of the insertion portion 57b of the second connecting portion 57 opposite to the side of the connecting portion 57c are in contact with the two circumferential edges of the notch portion 56b of the cylindrical member 56a of the first connecting portion 56, the furnace brazing is performed.

[0190] In contrast, for example, the front-to-back length of the end of the insertion portion 57b of the second connecting portion 57 opposite to the connecting portion 57c can be shorter than the length between the leading and trailing edges of the notch 56b of the cylindrical member 56a of the first connecting portion 56 in the circumferential direction. Specifically, a gap can be created between the front and rear edges of the insertion portion 57b and the front and rear edges of the notch 56b in the circumferential direction. By adjusting the size of the edge of the insertion portion 57b and the size of the notch 56b of the cylindrical member 56a in such a way that the size of this gap is below a predetermined value, the allowable positional relationship between the gas refrigerant connection pipe 19a and the gas manifold 50 during brazing in the furnace can be adjusted. For example, the ratio of the length of the edge of the insertion portion 57b in the front-to-back direction to the length of the notch 56b of the cylindrical member 56a in the front-to-back direction can be adjusted to, for example, 90% or more.

[0191] (8-4) Other implementation methods D

[0192] In the above embodiment, the following situation is illustrated: in the state where the surface near the end of the insertion portion 57b of the second connecting portion 57 on the side opposite to the connecting portion 57c is in contact with the circumferentially extending portion of the edge of the notch portion 56b of the cylindrical member 56a of the first connecting portion 56, furnace brazing is performed.

[0193] In contrast, for example, the circumferentially extending portions of the insert portion 57b of the second connecting portion 57 near the end opposite to the connecting portion 57c side and the notch portion 56b of the cylindrical member 56a of the first connecting portion 56, extending along their respective sides, may not contact each other, creating a gap that expands axially between them in the pipe connection portion 19x. By adjusting the position of the insert portion 57b and the notch portion 56b of the cylindrical member 56a to a predetermined value for the size of this gap, the permissible positional relationship between the gas refrigerant connection pipe 19a and the gas manifold 50 during brazing in the furnace can be adjusted. Although not particularly limited, the axial length of this gap in the pipe connection portion 19x may, for example, be less than or equal to the thickness of the first manifold member 51 of the gas manifold 50, preferably less than 50% of that thickness.

[0194] (8-5) Other implementation methods E

[0195] In the above embodiments, the following situation is illustrated: in-furnace brazing is performed under the condition that the detachment of the gas refrigerant connection pipe 19a from the gas manifold 50 is suppressed and the rotation of the gas refrigerant connection pipe 19a from the gas manifold 50 is also suppressed.

[0196] In contrast, in-furnace brazing can also be performed while suppressing the detachment of the gas refrigerant connection pipe 19a from the gas manifold 50 but not suppressing the rotation of the gas refrigerant connection pipe 19a from the gas manifold 50, or in a state where the detachment of the gas refrigerant connection pipe 19a from the gas manifold 50 is not suppressed but the rotation of the gas refrigerant connection pipe 19a from the gas manifold 50 is suppressed.

[0197] (8-6) Other implementation methods F

[0198] In the positioning of the gas refrigerant connection pipe 19a in the above embodiment, the following example is given: the cylindrical member 56a is fixed to the pipe connection portion 19x by the first screw 56s, and the insertion portion 57b of the connecting piece 57a is inserted into the notch portion 56b of the cylindrical member 56a, thereby determining the position of the gas refrigerant connection pipe 19a relative to the gas manifold 50.

[0199] In contrast, it can also be done through Figure 16 , Figure 17 The configuration shown determines the location of the gaseous refrigerant connection piping 19a.

[0200] In this configuration, the first connecting portion 56 has a cylindrical member 356a without the notch 56b in the cylindrical member 56a of the above embodiment, and a common screw 356s replacing the first screw 56s. Furthermore, in this configuration, the second connecting portion 57 has a connecting piece 357a and a second screw 57s. The connecting piece 357a has a through hole 57x instead of the insertion portion 57b in the connecting piece 57a of the above embodiment.

[0201] Furthermore, in this configuration, the manifold fixing portion 57d of the second connecting portion 57 extends to abut against the circumferential surface of the cylindrical member 356a, and the connecting portion 57c contacts the circumferential surface of the cylindrical member 356a. A through hole 57x is provided in the connecting portion 57c of the connecting piece 357a and extends through the connecting portion 57c in the plate thickness direction.

[0202] In the above configuration, similar to the embodiment described above, the second connecting portion 57 is fixed to the first manifold component 51 by screwing in the second connecting hole 57z with the manifold fixing hole 51z connected by the second screw 57s. In this state, by screwing in the common screw 356s with the pipe fixing hole 19z, the first connecting hole 56z, and the through hole 57x connected, not only can the cylindrical component 356a be fixed to the pipe connecting portion 19x, but the second connecting portion 57 can also be fixed to the pipe connecting portion 19x. Furthermore, since the second connecting portion 57 is fixed to the first manifold component 51, the pipe connecting portion 19x can be fixed to the first manifold component 51. In this case, the shaft of the common screw 356s is surrounded by the circumferential surface of the through hole 57x of the connecting part 57c. Therefore, the rotation of the pipe connection part 19x and the cylindrical member 356a is restricted, and the movement of the pipe connection part 19x and the cylindrical member 356a in the direction of separation from the first manifold member 51 is also restricted.

[0203] Furthermore, the through hole 57x provided in the connecting portion 57c of the connecting piece 357a can be a hole with a diameter larger than that of the common screw 356s, or a threaded groove can be provided on the inner circumference of the through hole 57x to engage with the threaded teeth of the common screw 356s. When the diameter of the through hole 57x is larger than that of the common screw 356s, the connecting portion 57c is fixed by being clamped by the circumferential surface of the pipe connecting portion 19x and the head of the common screw 356s by screwing the end of the common screw 356s into the pipe fixing hole 19z. Furthermore, when a threaded groove is provided on the inner circumference of the through hole 57x, the common screw 356s is fixed by screwing into both the through hole 57x and the pipe fixing hole 19z.

[0204] (8-7) Other implementation methods G

[0205] In the other embodiment F described above, the following case is illustrated: the position of the gas refrigerant connection pipe 19a relative to the gas manifold 50 is determined by fixing the connecting part 57c to the cylindrical member 356a using a common screw 356s.

[0206] In contrast, it can also be done through Figure 18 The configuration shown determines the location of the gaseous refrigerant connection piping 19a.

[0207] In this configuration, the connecting part 57c is integrated with the circumferential surface of the cylindrical part 456a by welding or the like, and the cylindrical part 456a and the connecting piece 457a constitute a single component.

[0208] Specifically, the connecting piece 457a is a structure in which the connecting piece 357a in other embodiments F does not have a through hole 57x. Furthermore, the cylindrical member 456a is a structure in which the cylindrical member 56a of the above embodiment or the cylindrical member 356a of other embodiments F has a first connecting hole 456z instead of the first connecting hole 56z. Moreover, the pipe connection portion 19x of this structure is provided with a pipe fixing hole 419z instead of the pipe fixing hole 19z in the pipe connection portion 19x of the above embodiment and other embodiments F. Here, the first connecting hole 456z and the pipe fixing hole 419z are configured to communicate with each other at a position that does not overlap with the connecting part 57c when it is desired to determine the position of the gas refrigerant connection pipe 19a relative to the gas manifold 50.

[0209] In the above configuration, the second connecting portion 57 is fixed to the first manifold component 51 by screwing it with the second screw 57s while the second connecting hole 57z is communicating with the manifold fixing hole 51z. In this state, the pipe connecting portion 19x is inserted into the cylindrical member 456a, which is integrated with the connecting portion 57c of the second connecting portion 57, and screwed in with the first connecting hole 456z communicating with the pipe fixing hole 419z by the first screw 456s. Thus, the cylindrical member 456a can be fixed relative to the pipe connecting portion 19x, and the second connecting portion 57, which is integrated with the cylindrical member 456a, can also be fixed relative to the pipe connecting portion 19x. Furthermore, since the second connecting portion 57 is fixed to the first manifold component 51, the pipe connecting portion 19x can also be fixed to the first manifold component 51. In this case, by fixing the second connecting portion 57, which is integrated with the cylindrical member 456a, to the first manifold member 51, the rotation of the piping connection portion 19x and the cylindrical member 356a is restricted, and the movement of the piping connection portion 19x and the cylindrical member 356a in the direction of separation from the first manifold member 51 is also restricted.

[0210] (Postscript)

[0211] The embodiments of this disclosure have been described above, but it should be understood that various changes in manner and details can be made without departing from the spirit and scope of this disclosure as set forth in the claims.

[0212] Label Explanation

[0213] 1. Air conditioning unit

[0214] 11 Outdoor heat exchanger (heat exchanger)

[0215] 19 First Gas Refrigerant Pipe

[0216] 19a Gas Refrigerant Connection Piping (Refrigerant Piping)

[0217] 19x Piping Connections

[0218] 19y piping opening

[0219] 19z Pipe Fixing Hole

[0220] 20 Liquid Refrigerant Pipe

[0221] 20a Liquid Refrigerant Connection Piping

[0222] 27 Heat Exchange Section

[0223] 28 Flat tube (heat transfer tube)

[0224] 30-fold return manifold

[0225] 40 entrance and exit manifolds

[0226] 50 Gas manifold (manifold)

[0227] 51 First manifold component

[0228] 51a first plate-shaped part

[0229] 51b Semicircular shape

[0230] 51x connection opening

[0231] 51z manifold fixing hole

[0232] 54c claw

[0233] 56 First connecting part (connecting part)

[0234] 56a cylindrical component

[0235] 56b Notch (First Shape Part)

[0236] 56s first screw

[0237] 56x Insertion Side Opening

[0238] 56y connection side opening

[0239] 56z First Connecting Hole

[0240] 57 Second connecting part (connecting part)

[0241] 57a connecting piece

[0242] 57b Insertion section (second shape part)

[0243] 57c Liaison Department

[0244] 57d manifold fixing part

[0245] 57s second screw

[0246] 57z Second Connection Hole

[0247] 58 Connecting Section

[0248] 60 liquid manifold

[0249] 119z Pipe Fixing Hole

[0250] 156b gap (first shape part, opening)

[0251] 156s third screw

[0252] 156z third connection hole

[0253] 256a fixing plate

[0254] 256s fourth screw

[0255] 256z fourth connection hole

[0256] Existing technical documents

[0257] Patent documents

[0258] Patent Document 1: Japanese Patent Application Publication No. 2023-102026

Claims

1. A heat exchanger (11) comprising: Multiple heat transfer tubes (28); A manifold (50) is connected to a plurality of the heat transfer tubes; Refrigerant piping (19a), which is connected to the manifold; and A connection part (58) separate from the manifold and the refrigerant piping is provided at the connection between the manifold and the refrigerant piping. The connecting part includes metal and brazing filler metal.

2. The heat exchanger according to claim 1, wherein, The connecting portion restricts the movement of the piping connecting portion (19x), which is the connecting part of the refrigerant piping, in the direction in which the piping connecting portion extends.

3. The heat exchanger according to claim 1 or 2, wherein, The refrigerant piping is a round pipe. The connecting portion restricts the rotation of the piping connecting portion (19x), which is the connecting part of the refrigerant piping, with the direction in which the piping connecting portion extends as the direction of rotation axis.

4. The heat exchanger according to any one of claims 1 to 3, wherein, The connecting portion includes: a first connecting portion (56) fixed to a piping connecting portion (19x) that serves as the connecting part of the refrigerant piping; and a second connecting portion (57) fixed to the manifold. The second connecting part restricts the movement of the first connecting part.

5. The heat exchanger according to claim 4, wherein, Viewed from the direction extending from the piping connection portion, the first connection portion covers the periphery of the piping connection portion.

6. The heat exchanger according to claim 4 or 5, wherein, The first connecting portion has a first shaped portion (56b, 156b) partially disposed in the circumferential direction of the pipe connecting portion. The refrigerant piping is a round pipe. The second connection portion has a second shape portion (57b), which cooperates with the first shape portion to restrict the rotation of the piping connection portion with the direction in which the piping connection portion extends as the axis of rotation.

7. The heat exchanger according to claim 6, wherein, The first connection portion has a cylindrical component (56a) that covers the surrounding piping connection portion. The first shaped portion is an opening (156b) or a notch (56b) provided in the cylindrical component. The second shaped portion is inserted radially into the opening or the notch toward the pipe connection portion.

8. The heat exchanger according to claim 4 or 5, wherein, The second connecting part is fixed to the first connecting part, or fixed to the piping connection part via the first connecting part, or integrated with the first connecting part.

9. The heat exchanger according to claim 1 or 2, wherein, The manifold has a first manifold component (51) that includes the connecting portion of the manifold. The first manifold component has a semi-circular part (51b) that is semi-circular when viewed from the length direction of the first manifold component.

10. The heat exchanger according to any one of claims 1 to 9, wherein, The refrigerant piping and the manifold do not contain brazing filler metal.

11. An air conditioning device (1) comprising a heat exchanger as described in any one of claims 1 to 10.

12. A method for manufacturing a heat exchanger (11), the heat exchanger (11) having a plurality of heat transfer tubes (28), a manifold (50) connected to the plurality of heat transfer tubes, and a refrigerant piping (19a) connected to the manifold, wherein, The method for manufacturing the heat exchanger (11) includes: In the positioning process, a connecting part (58) containing metal and brazing filler is provided at the connection between the manifold and the refrigerant piping, and the position of the refrigerant piping relative to the manifold is determined by means of the connecting part; as well as The process of brazing the refrigerant piping to the manifold while it is in a positioned state during the positioning process.

13. The method for manufacturing a heat exchanger according to claim 12, wherein, The refrigerant piping is a round pipe. In the positioning process, the connecting part is used to restrict the rotation of the piping connection portion (19x) with the direction in which the piping connection portion extends being the axis of rotation. The piping connection portion (19x) is the connection part of the refrigerant piping that connects to the manifold. In the brazing process, the refrigerant piping is brazed to the manifold under the restricted conditions.

14. The method of manufacturing a heat exchanger according to claim 12 or 13, wherein, The brazing process is carried out in a furnace.

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