WO2025079135A1 - Heat exchanger, refrigeration cycle device, and refrigeration cycle system - Google Patents

Abstract

In heat exchangers in which an airflow temperature boundary layer develops readily in a heat exchange member, localized frost formation and other such causes may lead to abnormalities or degradation in heat exchange performance. A heat exchanger according to the present invention comprises a plurality of heat exchanger members arrayed in a first direction. Each of the plurality of heat exchange members has: a flat tube whose tube axis extends along a second direction that intersects the first direction and inside which a refrigerant circulates; and an outer fin joined to a flat portion of the flat tube. In this heat exchanger, which is for exchanging heat between a refrigerant and air circulating in a gap formed between adjacent heat exchange members among the plurality of heat exchange members, a heat transfer promoting structure is formed on the outer fin to promote heat transfer. The outer fin has: a body portion disposed between the flat tubes of adjacent heat exchange members; and one or two protruding portions extending from the body portion to an upwind or downwind side in a third direction, which is a direction intersecting the first and second directions and the direction of air circulation. The body portion has a planar body base surface provided along the flat portion of the flat tube and joined to the flat portion. Each of the one or two protruding portions has: a protruding portion base surface which extend in the third direction from the body base surface and which is located in the same virtual plane as the body base surface; and a protruding portion curved portion which is provided adjacently to the protruding portion base surface in the second direction and which is curved relative to the protruding portion base surface so as to protrude in the first direction. A refrigeration cycle device and a refrigeration cycle system according to the present invention comprise the above heat exchanger.

Description

HEAT EXCHANGER, REFRIGERATION CYCLE DEVICE, AND REFRIGERATION CYCLE SYSTEM

This disclosure relates to a heat exchanger equipped with flat tubes and fins, a refrigeration cycle device, and a refrigeration cycle system.

In some heat exchangers, a plurality of heat exchange members each having a flat tube and a fin (outer fin) are arranged in a first direction, and a gap through which air flows is formed between adjacent heat exchange members. In such heat exchangers, the flat tubes are arranged so that the tube axis is along a second direction intersecting the first direction, and the outer fins (heat transfer plate) are provided so as to be along the flat tube in the second direction, and the flat tubes and the outer fins are joined to each other (see, for example, Patent Document 1). In the heat exchanger of Patent Document 1, the heat transfer plate has a main body portion formed so as to be along one side of the flat tube in the first direction and extend in the second direction, and two extension portions extending from the main body portion to the upstream side and downstream side of the air flow so as to protrude from the end of the flat tube. The heat exchanger exchanges heat between the air flowing through the gap formed between the heat exchange members and the refrigerant flowing in the flat tube. In the heat exchanger of Patent Document 1, each extension is flat, and the ends of the main body of the heat transfer plate that connect to each extension are overlapping parts formed to fit along the outer circumferential surface of the curved ends of the flat tubes.

International Publication No. 2019/026240

In the heat exchanger of Patent Document 1, the heat transfer area with the air is expanded by the weave (overlapped portion) of the heat transfer plate. However, the weave of the heat transfer plate (outer fin) covers the outer peripheral surface of the end of the flat tube, and the main body is connected to the flat extension portion at this weave, so a temperature boundary layer of the airflow develops in the heat exchange member formed by joining the flat tube and the heat transfer plate. Therefore, when a heat transfer promotion structure that promotes heat transfer is formed in the outer fin, it is difficult to obtain a sufficient heat transfer promotion effect.

The present disclosure has been made to solve the problems described above, and aims to provide a heat exchanger, refrigeration cycle device, and refrigeration cycle system that can suppress the development of a temperature boundary layer in the airflow in the heat exchange member and sufficiently achieve the heat transfer promotion effect.

The heat exchanger according to the present disclosure comprises a plurality of heat exchange members arranged in a first direction, each of which has a flat tube whose tube axis extends along a second direction intersecting the first direction and through which a refrigerant flows, and an outer fin joined to a flat portion of the flat tube, and in the heat exchanger which performs heat exchange between the refrigerant and air flowing through gaps formed between adjacent heat exchange members of the plurality of heat exchange members, the outer fin is formed with a heat transfer promotion structure which promotes heat transfer, and the outer fin comprises a main body portion which is arranged between the flat tubes of the adjacent heat exchange members, and a heat exchanger extending from the main body portion to the and one or two protrusions extending to the windward or leeward side in a third direction that is a direction intersecting the first direction and the second direction and is the air flow direction, the main body has a planar main body base surface that is arranged along the flat portion of the flat tube and joined to the flat portion, and each of the one or two protrusions has a protrusion base surface that extends from the main body base surface in the third direction and is arranged on the same imaginary plane as the main body base surface, and a protrusion bend that is adjacent to the protrusion base surface in the second direction and is bent relative to the protrusion base surface to protrude in the first direction.

The refrigeration cycle device according to the present disclosure also includes a refrigerant circuit in which the above-mentioned heat exchanger, a compressor, a flow path switching device, an indoor heat exchanger, and a throttling device are connected by refrigerant pipes.

The refrigeration cycle system according to the present disclosure also includes a refrigerant circuit in which the above-mentioned heat exchanger, compressor, flow path switching device, indoor heat exchanger, and throttling device are connected by refrigerant pipes, and a control device that controls the frequency of the compressor, the switching of the flow path switching device, and the opening of the throttling device.

In the heat exchanger, refrigeration cycle device, and refrigeration cycle system of the present disclosure, a heat transfer promotion structure is formed in the outer fin, and each protrusion of the outer fin has a protrusion base surface and a protrusion bend, and the protrusion base surface of each protrusion in the outer fin extends in a third direction from the main body base surface and is disposed on the same imaginary plane as the main body base surface. Therefore, compared to a conventional configuration in which the weave of the main body portion is connected to a flat extension portion (protrusion) in a heat transfer plate (outer fin), in the present disclosure, the development of a temperature boundary layer in the airflow is suppressed, allowing the heat transfer promotion structure to fully demonstrate its function and the heat transfer promotion effect to be fully obtained.

1 is a schematic front view showing a heat exchanger according to a first embodiment of the present invention; FIG. 2 is a refrigerant circuit diagram of a refrigeration cycle device equipped with the heat exchanger of FIG. 1. FIG. 2 is a schematic plan view of the heat exchanger shown in FIG. 1 . FIG. 2 is a schematic side view of the heat exchanger shown in FIG. 1 . 5 is a partial schematic cross-sectional view showing the AA cross section of the heat exchanger element shown in FIG. 4. FIG. 2 is a partial perspective view showing three heat exchange members of the heat exchanger shown in FIG. 1 . 10 is a perspective view showing a modified example of the heat exchange member in the heat exchanger according to the first embodiment. FIG. FIG. 11 is a perspective view showing the configuration of a main part of a heat exchanger according to a second embodiment. 9 is a cross-sectional view taken along the line BB of one heat exchange member arranged on the leftmost side among the main parts shown in FIG. 8. 9 is a cross-sectional view taken along the line CC of one heat exchange member disposed on the leftmost side of the main portion shown in FIG. 8. 9 is a cross-sectional view taken along the line DD of two heat exchange members arranged on the leftmost side of the main part shown in FIG. 8. 9 is a cross-sectional view taken along the line E-E of two heat exchange members arranged on the leftmost side of the main part shown in FIG. 8. FIG. 11 is a perspective view showing the configuration of a main part of a heat exchanger according to a third embodiment. FIG. 11 is a perspective view showing a first modified example of a main part of the heat exchanger according to the third embodiment. FIG. 11 is a perspective view showing a second modified example of the main part of the heat exchanger according to the third embodiment. FIG. 11 is a perspective view showing a third modified example of the main part of the heat exchanger according to the third embodiment. FIG. 11 is a perspective view showing a fourth modified example of the main part of the heat exchanger according to the third embodiment. FIG. 11 is a perspective view showing a fifth modified example of the main part of the heat exchanger according to the third embodiment. FIG. 11 is a perspective view showing a configuration of a heat exchange member in a heat exchanger according to a fourth embodiment. 20 is a cross-sectional view of the heat exchange member of FIG. 19 taken along the line FF. FIG. 13 is a perspective view showing the configuration of a main part of a heat exchanger according to a fifth embodiment.

The heat exchanger according to the first embodiment will be described below with reference to the drawings. Note that in the following drawings, including FIG. 1, the relative dimensional relationships and shapes of the components may differ from the actual ones. In the following drawings, the same reference numerals are used to refer to the same or equivalent components, and this applies throughout the entire specification. In addition, to facilitate understanding, directional terms (e.g., "upper," "lower," "right," "left," "front," "rear," etc.) are used as appropriate, but these notations are merely used for the sake of convenience and do not limit the arrangement or orientation of the device or parts. In the specification, the positional relationships between the components, the extension direction of each component, and the arrangement direction of each component are, in principle, those when the heat exchanger is installed in a usable state.

Embodiment 1.
FIG. 1 is a front schematic diagram showing a heat exchanger 101 according to the first embodiment. In FIG. 1, the direction of refrigerant flow when the heat exchanger 101 is used as an evaporator is indicated by a solid white arrow. As shown in FIG. 1, the heat exchanger 101 includes a plurality of heat exchange members 10 arranged in a first direction D1. Each heat exchange member 10 has a flat tube 20 extending in a second direction D2 intersecting the first direction D1. The heat exchanger 101 also includes a first header 40 to which one end 13a of the flat tube 20 of the plurality of heat exchange members 10 in the extension direction (second direction D2) is connected, and a second header 50 to which the other end 13a of the flat tube 20 of the plurality of heat exchange members 10 in the extension direction is connected. A gap G through which air flows is formed between the heat exchange members 10 adjacent to each other in the first direction D1.

(Refrigeration cycle device 100)
Fig. 2 is a refrigerant circuit diagram of a refrigeration cycle apparatus 100 equipped with the heat exchanger 101 of Fig. 1. As shown in Figs. 1 and 2, the heat exchanger 101 constitutes a part of a refrigerant circuit 100c of the refrigeration cycle apparatus 100.

In the embodiment, the refrigeration cycle device 100 is described as being applied to an air conditioner. However, the refrigeration cycle device 100 can also be applied to devices other than air conditioners, such as refrigeration cycle devices used for purposes such as refrigerators, freezers, vending machines, refrigeration devices, or water heaters.

The refrigeration cycle device 100 has a compressor 102, a heat exchanger 101, a throttling device 105, an indoor heat exchanger 104, and a flow path switching device 103. In this example, the compressor 102, the heat exchanger 101, the throttling device 105, and the flow path switching device 103 are provided in the outdoor unit 100A, and the indoor heat exchanger 104 is provided in the indoor unit 100B.

The compressor 102, flow path switching device 103, heat exchanger 101, throttling device 105, and indoor heat exchanger 104 are connected to each other via refrigerant pipes to form a refrigerant circuit 100c in which the refrigerant can circulate. In the refrigeration cycle device 100, the operation of the compressor 102 performs a refrigeration cycle in which the refrigerant circulates through the compressor 102, heat exchanger 101, throttling device 105, and indoor heat exchanger 104 while undergoing a phase change.

The outdoor unit 100A is provided with an outdoor fan 107 that forces outdoor air through the heat exchanger 101. The indoor unit 100B is provided with an indoor fan 106 that forces indoor air through the indoor heat exchanger 104.

Compressor 102 draws in low-temperature, low-pressure refrigerant, compresses it, and discharges high-temperature, high-pressure refrigerant. Compressor 102 is, for example, an inverter compressor whose capacity, which is the amount of refrigerant discharged per unit time, is controlled by changing the operating frequency.

Heat exchanger 101 functions as an evaporator or a condenser, and exchanges heat between the refrigerant and the outdoor air generated by the operation of outdoor fan 107, evaporating the refrigerant into a gas or condensing it into a liquid. Heat exchanger 101 functions as an evaporator during heating operation, and as a condenser during cooling operation.

The indoor heat exchanger 104 functions as an evaporator or a condenser, and exchanges heat between the indoor air generated by the operation of the indoor fan 106 and the refrigerant, evaporating the refrigerant into a gas or condensing the refrigerant into a liquid. The indoor heat exchanger 104 functions as a condenser during heating operation and as an evaporator during cooling operation.

The throttling device 105 reduces the pressure of the refrigerant to expand it. The throttling device 105 is, for example, an electronic expansion valve that can adjust the opening of the throttling device. By adjusting the opening, the pressure of the refrigerant flowing into the indoor heat exchanger 104 is controlled during cooling operation, and the pressure of the refrigerant flowing into the heat exchanger 101 is controlled during heating operation.

The flow path switching device 103 is, for example, a four-way valve, and switches between cooling operation and heating operation by switching the direction of the refrigerant flow. Note that instead of a four-way valve, a combination of a two-way valve and a three-way valve may also be used as the flow path switching device 103.

The indoor fan 106 is provided near the indoor heat exchanger 104 and supplies indoor air to the indoor heat exchanger 104, and the amount of air sent to the indoor fan 106 is adjusted by controlling its rotation speed. The outdoor fan 107 is provided near the heat exchanger 101 and supplies outdoor air to the heat exchanger 101, and the amount of air sent to the outdoor fan 107 is adjusted by controlling its rotation speed.

The outdoor unit 100A and the indoor unit 100B are configured to be able to communicate with each other. The refrigeration cycle device 100 is equipped with a control device 108 that controls the operation of the refrigeration cycle device 100, and the control device 108 is mounted, for example, on the outdoor unit 100A. The control device 108 controls the switching of the flow path switching device 103, the frequency of the compressor 102, the rotation speeds of the indoor fan 106 and the outdoor fan 107, and the opening degree of the throttling device 105. The control device 108 is composed of, for example, a microcomputer having a control arithmetic processing device such as a CPU (Central Processing Unit). The control device 108 also has a storage device and has data in the form of a program that is a processing procedure related to control, etc. Then, the control arithmetic processing device executes processing based on the program data to realize control.

The operation of the refrigeration cycle device 100 can be switched between cooling operation and heating operation. In FIG. 2, the direction of refrigerant flow during cooling operation is indicated by dashed arrows, and the direction of refrigerant flow during heating operation is indicated by solid arrows.

When the refrigeration cycle device 100 is in cooling operation, the flow path switching device 103 is switched so as to guide the refrigerant from the compressor 102 to the heat exchanger 101 and the refrigerant from the indoor heat exchanger 104 to the compressor 102, as shown by the dashed lines in FIG. 2. Then, the refrigerant compressed by the compressor 102 is sent to the heat exchanger 101. In the heat exchanger 101, the refrigerant releases heat to the outdoor air and is condensed. After this, the refrigerant is sent to the throttling device 105, where it is decompressed, and then sent to the indoor heat exchanger 104. After this, the refrigerant absorbs heat from the indoor air in the indoor heat exchanger 104 and evaporates, and then returns to the compressor 102. Therefore, during cooling operation of the refrigeration cycle device 100, the heat exchanger 101 functions as a condenser, and the indoor heat exchanger 104 functions as an evaporator.

When the refrigeration cycle device 100 is in heating operation, the flow path switching device 103 is switched so as to guide the refrigerant from the compressor 102 to the indoor heat exchanger 104 and the refrigerant from the heat exchanger 101 to the compressor 102, as shown by the solid lines in FIG. 2. Then, the refrigerant compressed by the compressor 102 is sent to the indoor heat exchanger 104. In the indoor heat exchanger 104, the refrigerant releases heat to the indoor air and is condensed. After this, the refrigerant is sent to the throttling device 105, where it is decompressed, and then sent to the heat exchanger 101. After this, the refrigerant absorbs heat from the outdoor air in the heat exchanger 101 and evaporates, and then returns to the compressor 102. Therefore, during heating operation of the refrigeration cycle device 100, the heat exchanger 101 functions as an evaporator, and the indoor heat exchanger 104 functions as a condenser.

FIG. 3 is a schematic plan view of the heat exchanger 101 shown in FIG. 1. FIG. 4 is a schematic side view of the heat exchanger 101 shown in FIG. 1. FIG. 5 is a schematic partial cross-sectional view showing the A-A cross section of the heat exchange member 10 shown in FIG. 4. FIG. 6 is a partial perspective view showing the three heat exchange members 10 of the heat exchanger 101 shown in FIG. 1. In FIG. 3 and FIG. 4, the direction of the refrigerant flow when the heat exchanger 101 is used as an evaporator is indicated by solid white arrows. In FIG. 3 to FIG. 5, the direction of the air flow is indicated by dashed white arrows. Below, the schematic configuration of the heat exchanger 101 will be described based on FIG. 1 and FIG. 3 to FIG. 6. Note that the illustrated heat exchanger 101 is only an example, and the configuration is not limited to the configuration described in the embodiment, and can be appropriately changed within the scope of the technology related to the embodiment.

As shown in FIG. 6, the heat exchange member 10 is composed of flat tubes 20 and outer fins 30 joined to the flat tubes 20. The flat tubes 20 are arranged so that their tube axes are aligned with the second direction D2. Also, as shown in FIG. 5, the outer fins 30 are arranged between adjacent flat tubes 20. As shown in FIG. 6, the outer fins 30 are formed with a heat transfer promotion structure 33, such as louvers or slits, that promotes heat transfer. As described with reference to FIG. 1, a gap G is formed in the heat exchanger 101, and air flows through this gap G along a third direction D3 that intersects with the first direction D1 and the second direction D2 in the heat exchanger 101, as shown in FIG. 3 to FIG. 5.

In the following explanation, the extension direction of the heat exchange member 10 shown in FIG. 1 (extension direction of the flat tubes 20), i.e., the second direction D2, is defined as the up-down direction parallel to the direction of gravity. The arrangement direction of the multiple heat exchange members 10, i.e., the first direction D1, is defined as the left-right direction perpendicular to the direction of gravity. The third direction D3 parallel to the air flow direction in the heat exchanger 101 is defined as the depth direction perpendicular to the first direction D1 and the second direction D2. The arrangement of the heat exchanger 101 is not limited to the above case.

(header)
1, 3, and 4, the first header 40 and the second header 50 are arranged with their longitudinal directions facing the arrangement direction (first direction D1) of the heat exchange members 10. That is, the longitudinal directions of the first header 40 and the second header 50 are parallel to each other. In the following description, the first header 40 and the second header 50 may be simply referred to as headers without distinction.

The first header 40 and the second header 50 are cylindrical bodies with both ends closed, and a space is formed inside through which the refrigerant flows. The first header 40 and the second header 50 extend in the first direction D1, and in the example shown in Figures 1, 3, and 4, have a rectangular parallelepiped outer shape, and in a cross section perpendicular to the first direction D1, have a rectangular cross-sectional shape with a long side in the third direction D3 (see Figure 4).

In addition, in Figures 1, 3, and 4, the first header 40 and the second header 50 each have a rectangular parallelepiped outer shape, but the outer shapes of the first header 40 and the second header 50 are not limited to the shapes shown in the figures. The outer shapes of the first header 40 and the second header 50 may be, for example, a circular cylinder or an elliptical cylinder, and the cross-sectional shapes of the first header 40 and the second header 50 may be changed as appropriate. In addition, the structure of the first header 40 and the second header 50 may be, other than being configured as a cylindrical body with both ends closed as described above, for example, a laminated plate-like body with slits formed therein that form the flow path within the header. In addition, the first header 40 and the second header 50 may be configured to have different outer shapes or cross-sectional shapes from each other.

The first header 40 and the second header 50 each have a refrigerant flow port 41 and 51 through which the refrigerant can flow in and out. Specifically, the refrigerant flow port 41 is provided in a wall portion constituting one end of the first header 40 in the first direction D1 (the left wall portion of the first header 40 in FIG. 1). The refrigerant flow port 51 is provided in a wall portion constituting one end of the second header 50 in the first direction D1 (the right wall portion of the second header 50 in FIG. 1). When the heat exchanger 101 functions as an evaporator, the refrigerant flow port 41 becomes the refrigerant inlet in the heat exchanger 101, and the refrigerant flow port 51 becomes the refrigerant outlet in the heat exchanger 101. When the heat exchanger 101 functions as a condenser, the refrigerant flow port 51 becomes the refrigerant inlet in the heat exchanger 101, and the refrigerant flow port 41 becomes the refrigerant outlet in the heat exchanger 101. In addition, the positions at which the refrigerant flow ports 41 and 51 are provided in the first header 40 and the second header 50 are not limited to the positions described above and can be changed as appropriate.

Furthermore, a plurality of insertion holes (not shown) are formed in the header upper wall portion of the first header 40 located on the lower side in the heat exchanger 101, and the plurality of insertion holes are arranged in parallel in the first direction D1 corresponding to the plurality of heat exchange members 10. The plurality of insertion holes are holes into which the lower ends of the respective plurality of heat exchange members 10 (particularly, the lower 13a of the flat tubes 20) are inserted, and penetrate the header upper wall portion of the first header 40 in the thickness direction, i.e., in the second direction D2.

In addition, a plurality of insertion holes (not shown) are formed in the header lower wall of the second header 50 located at the upper side in the heat exchanger 101, and the plurality of insertion holes are arranged in parallel in the first direction D1 corresponding to the plurality of heat exchange members 10. The plurality of insertion holes are holes into which the upper ends of the respective plurality of heat exchange members 10 (particularly, the upper 13b of the flat tubes 20) are inserted, and penetrate the header lower wall of the second header 50 in the thickness direction, i.e., in the second direction D2.

In the multiple heat exchange members 10, the ends 13a and 13b of the flat tubes 20 are inserted into the first header 40 and the second header 50, respectively, and joined by a joining means such as brazing or adhesive.

Next, an example of the operation of the heat exchanger 101 when the heat exchanger 101 is used as an evaporator will be described. As shown in FIG. 1, a low-pressure gas-liquid two-phase refrigerant flows into the heat exchanger 101 from the refrigerant flow port 41. In the heat exchanger 101, the low-pressure gas-liquid two-phase refrigerant first flows into the first header 40, is distributed to each of the flat tubes 20 of the multiple heat exchange members 10 by the first header 40, and flows in multiple refrigerant flow paths 23 (see FIG. 6 described later) in each flat tube 20. In the refrigerant flow path 23 of each flat tube 20, the low-pressure gas-liquid two-phase refrigerant flows in the second direction D2 toward the second header 50 and passes through the flat tube 20. At this time, the low-pressure gas-liquid two-phase refrigerant exchanges heat with the air flowing through the gap G between adjacent heat exchange members 10 through the members that constitute the heat exchange member 10, radiating heat to the air and evaporating, becoming a low-pressure gas-state refrigerant. The low-pressure gaseous refrigerant from the flat tubes 20 flows into the second header 50 and merges in the second header 50. The low-pressure gaseous refrigerant that merges in the second header 50 flows out of the heat exchanger 101 (for example, the compressor 102 in FIG. 2) from the refrigerant flow port 41 provided in the second header 50.

(Heat exchange member 10)
5, the flat tube 20 is a flat porous tube having a cross-sectional shape that is flat in one direction, such as an oval shape, and having a plurality of refrigerant flow paths 23 formed by through holes therein. In a cross section perpendicular to the tube axis, the flat tube 20 has a pair of flat portions 21 that face each other in the first direction D1 and extend in the third direction D3, and a pair of curved portions 22 that are located at both ends of the flat portions 21 in the third direction D3 and curved outwardly. The flat tubes 20 are arranged in the first direction D1 with gaps G through which air flows, and extend along a second direction D2 that intersects with the first direction D1.

The flat tube 20 is, for example, an extruded tube formed by extrusion molding. However, without being limited thereto, the flat tube 20 may also be a roll-formed tube formed by bending a single rectangular flat plate-shaped member.

As shown in Figures 5 and 6, the heat exchange member 10 has a main body 31 disposed between the flat portions 21 of adjacent flat tubes 20 in the first direction D1, and a pair of protrusions 32 protruding from the main body 31 on both sides in the third direction D3. Note that in Figures 1 to 6, the heat exchange member 10 has the protrusions 32 on both the upwind side and the downwind side of the flat tubes 20 in the direction of the air flow indicated by the dotted white arrow, but it may have the protrusions 32 on only one of the upwind side and the downwind side.

As shown in Figures 5 and 6, the main body portion 31 has a plurality of main body base surfaces 31a that are brazed to the flat portion 21 of the flat tube 20, and a plurality of main body bent portions 31b that are bent in the negative direction of the first direction D1 (leftward in Figure 5) relative to the main body base surfaces 31a so as to move away from the flat portion 21. The main body base surfaces 31a are planar and substantially parallel to the flat portion 21 of the flat tube 20.

The main body bent portion 31b protrudes from the main body base surface 31a in the negative direction of the first direction D1 (leftward in FIG. 5). The main body bent portion 31b is composed of a first central portion 31d that constitutes the central portion of the main body bent portion 31b in the second direction D2, and first connection portions 31c that respectively connect the main body base surface 31a located above and below the first central portion 31d to the upper and lower edges of the first central portion 31d. In FIG. 6, the first central portion 31d of the main body bent portion 31b is planar and approximately parallel to the flat portion 21 of the flat tube 20, and each first connection portion 31c of the main body bent portion 31b is an inclined surface that is inclined with respect to the vertical direction (second direction D2).

The protrusion 32 has a plurality of protrusion base surfaces 32a extending in the third direction D3 from the ends of the plurality of main body base surfaces 31a in the third direction D3, and a plurality of protrusion bends 32b bent in the positive direction of the first direction D1 (to the right in FIG. 5) relative to the protrusion base surfaces 32a. The protrusion base surfaces 32a of the pair of protrusions 32 are provided on the same imaginary plane as the main body base surface 31a, and are each connected to the ends of both sides of the main body base surface 31a in the third direction D3.

The protrusion bend 32b protrudes from the protrusion base surface 32a in the positive direction of the first direction D1 (to the right in FIG. 5). The protrusion bend 32b is composed of a second central portion 32d that constitutes the central portion of the protrusion bend 32b in the second direction D2, and second connection portions 32c that respectively connect the protrusion base surface 32a located above and below the second central portion 32d to the upper and lower edges of the second central portion 32d. In FIG. 6, the second central portion 32d of the protrusion bend 32b is a plane that is approximately parallel to the imaginary plane on which the protrusion base surface 32a and the main body base surface 31a are provided, and each second connection portion 32c of the protrusion bend 32b is an inclined surface that is inclined from the vertical direction (second direction D2).

In embodiment 1, as shown in FIG. 5, in the heat exchange member 10, the bending direction of the main body bent portion 31b relative to the main body base surface 31a (leftward in FIG. 5) and the bending direction of the protrusion bent portion 32b relative to the protrusion base surface 32a (rightward in FIG. 5) are opposite in the first direction D1. Therefore, as shown in FIG. 6, in the plate-like member constituting the outer fin 30, a cut 30a is formed at the boundary between the main body bent portion 31b and the protrusion bent portion 32b.

As shown in Figures 1 and 6, the gap G, which is the air flow path of the heat exchanger 101, is a concept that includes not only the first space G1 formed between one outer fin 30 and the other flat tube 20 of adjacent heat exchange members 10, but also the second space G2 formed between the outer fin 30 (particularly the main body bend portion 31b) and the flat tube 20 of the same heat exchange member 10.

In the first embodiment, air also flows through the second space G2 between the main body bend 31b and the flat portion 21 of the flat tube 20 via the multiple slits 30a formed in the outer fin 30. The protruding bend 32b, which is provided on the outer fin 30 on the windward side of the main body bend 31b and bent in the opposite direction to the main body bend 31b, guides air into the second space G2.

FIG. 7 is a perspective view showing a modified example of the heat exchange member 10 in the heat exchanger 101 according to the first embodiment. As shown in FIG. 7, the second connection portion 32c of the protrusion 32 may have a folded structure 32cr. That is, in FIG. 6, the second connection portion 32c of the protrusion 32 is an inclined surface, but in the modified example of FIG. 7, the second connection portion 32c of the protrusion 32 has a mountain shape with a folded structure 32cr. In this modified example, the second space portion G2 can be secured while suppressing the protruding height of the protrusion bend portion 32b to the right. Therefore, when two adjacent heat exchange members 10 are viewed from the windward side, it is easy to provide a gap between the second center portion 32d of one of the protrusion bend portions 32b and the flat tube 20 of the heat exchange member 10 on the right.

1 to 6 and the modified example of FIG. 7, the width a of the base surface (main body base surface 31a and protruding portion base surface 32a) of the outer fin 30 in the second direction D2 is narrower than the width b of the bent portion (main body bent portion 31b and protruding portion bent portion 32b). The width a of the base surface in the second direction D2 of the outer fin 30 may be wider, narrower, or the same as the width b of the bent portion in the second direction. Although the heat transfer promotion structure 33 is not shown in FIG. 7, the heat transfer promotion structure 33 is formed on the outer fin 30 in the modified example of FIG. 7 as in the case of FIG. 6. By adjusting the width a of the base surface in the second direction D2 and the width b of the bent portion in the second direction D2, the flow of the airflow can be adjusted, and the airflow can be prevented from avoiding the heat transfer promotion structure 33.

The number of base surfaces (main body base surface 31a and protrusion base surface 32a) and bent portions (main body bent portions 31b and protrusion bent portions 32b) is not limited to the number shown in FIG. 1 or FIG. 7. In the above example, the protrusion bent portion 32b is bent in the positive direction of the first direction D1 (rightward in FIG. 5) relative to the protrusion base surface 32a, but this is not limited thereto. That is, the protrusion bent portion 32b may be bent in the negative direction of the first direction D1 (leftward in FIG. 5) relative to the protrusion base surface 32a. In the above example, the outer fin 30 is formed by bending one rectangular flat plate-shaped member, but this is not limited thereto. For example, the outer fin 30 may be formed by connecting multiple rectangular flat plate-shaped members.

In the example of FIG. 6, the heat transfer promotion structure 33 is a plurality of louvers. Also, in the example of FIG. 6, the heat transfer promotion structure 33 is formed in the planar second central portion 32d of each of the protruding portion 32 on the windward side and the protruding portion 32 on the leeward side of the outer fin 30.

The position where the heat transfer promotion structure 33 is provided on the outer fin 30 is not limited to the above position. For example, in FIG. 6, the heat transfer promotion structure 33 is provided on both the windward protrusion 32 and the leeward protrusion 32, but the heat transfer promotion structure 33 may be provided on only one of the pair of protrusions 32. In general, condensation is likely to occur on the part of the outer fin 30 facing the flat tubes 20, but when the heat transfer promotion structure 33 is provided on the windward protrusion 32, condensation is less likely to occur on the main body 31. In general, heat transfer is likely to deteriorate in the leeward protrusion 32 due to a decrease in temperature efficiency, but when the heat transfer promotion structure 33 is provided on the leeward protrusion 32, the deterioration of heat transfer due to a decrease in temperature efficiency in the leeward protrusion 32 is suppressed, and heat transfer is promoted.

Furthermore, in addition to the above-mentioned positions on the outer fin 30, i.e., the protrusions 32 on the windward side and the protrusions 32 on the leeward side, the heat transfer promotion structure 33 may be provided on the main body 31. When the heat transfer promotion structure 33 is provided on the main body 31, heat is transferred in an area with high fin efficiency, and heat transfer is promoted. Furthermore, since there is little distortion on the base surface (main body base surface 31a and protrusion base surface 32a) during manufacturing, it is easy to create the heat transfer promotion structure 33 on the base surface. Therefore, when the heat transfer promotion structure 33 is provided on the base surface, the heat transfer promotion effect is obtained as designed, improving manufacturability and performance.

The protrusion 32 may be provided on only one of the upwind and downwind sides of the flat tube 20. However, in a configuration in which the protrusions 32 are provided on both the upwind and downwind sides as shown in FIG. 6, and the protrusions 32 and the heat transfer promotion structure 33 are provided symmetrically with respect to the tube axis of the flat tube 20 in the third direction D3, assembly errors due to differences in the orientation of the third direction D3 (front-to-back direction) during manufacturing are eliminated, improving manufacturability.

As described above, the heat exchanger 101 according to the first embodiment includes a plurality of heat exchange members 10 arranged in a first direction D1, each of which has a flat tube 20 whose tube axis extends along a second direction D2 intersecting the first direction D1 and through which a refrigerant flows, and an outer fin 30 joined to the flat portion 21 of the flat tube 20, and performs heat exchange between the air flowing through the gap G formed between adjacent heat exchange members 10 of the plurality of heat exchange members 10 and the refrigerant. The outer fin 30 has a heat transfer promotion structure 33 that promotes heat transfer. The outer fin 30 has a main body portion 31 disposed between the flat tubes 20 of the adjacent heat exchange members 10, and one or two protrusions 32 extending from the main body portion 31 to the windward side or the leeward side of the third direction D3, which is the air flow direction. The third direction D3 is a direction intersecting the first direction D1 and the second direction D2. The main body 31 has a planar main body base surface 31a that is provided along the flat portion 21 of the flat tube 20 and is joined to the flat portion 21. Each of the one or two protrusions 32 has a protrusion base surface 32a that extends from the main body base surface 31a in the third direction D3 and is arranged on the same imaginary plane as the main body base surface 31a, and a protrusion bend portion 32b that is provided adjacent to the protrusion base surface 32a in the second direction D2 and is bent so as to protrude in the first direction D1 relative to the protrusion base surface 32a.

In this way, each protrusion 32 of the outer fin 30 has a protrusion base surface 32a and a protrusion bend 32b, and thus has a shape with peaks and valleys. In the outer fin 30, the protrusion base surface 32a of each protrusion 32 extends from the main body base surface 31a in the third direction D3, and is disposed on the same imaginary plane as the main body base surface 31a. Therefore, compared to a conventional configuration in which the weave of the main body portion is connected to a flat extension portion (protrusion) in a heat transfer plate (outer fin), in the present disclosure, the development of a temperature boundary layer in the airflow is suppressed, and the heat transfer promotion effect can be sufficiently obtained.

Furthermore, in the heat exchanger 101 according to the second embodiment, one or two protrusions 32 include a protrusion 32 that extends from the main body 31 to the windward side in the third direction D3, which is the air flow direction. A heat transfer promotion structure 33 is formed on at least the protrusion 32 that extends to the windward side of the outer fin 30. This suppresses the occurrence of condensation in the main body 31 that is provided along the flat tubes 20.

Furthermore, one or two of the protrusions 32 include a protrusion 32 that extends from the main body 31 to the downwind side in the third direction D3, which is the air flow direction. A heat transfer promotion structure 33 is formed at least on the protrusion 32 that extends to the downwind side of the outer fin 30. This prevents deterioration of heat transfer due to a decrease in temperature efficiency in the protrusion 32 on the downwind side, and promotes heat transfer.

The outer fin 30 has a protrusion 32 extending from the main body 31 to the windward side in the third direction D3 and a protrusion 32 extending to the leeward side. The outer fin 30 has a heat transfer promotion structure 33 formed symmetrically in the third direction D3 with respect to the tube axis.

This eliminates assembly errors caused by differences in the orientation of the third direction D3 (front-to-back direction) during manufacturing and assembly, improving manufacturability.

Furthermore, the protrusion bend 32b has a flat portion (second central portion 32d) parallel to the imaginary plane on which the main body base surface 31a and the protrusion base surface 32a are arranged. A heat transfer promotion structure 33 that promotes heat transfer is formed on at least this flat portion of the protrusion bend 32b in the outer fin 30. This makes it easier to create the heat transfer promotion structure 33 even when the heat transfer promotion structure 33 is provided on the protrusion bend 32b.

Furthermore, the heat transfer promotion structure 33 may be provided on only one or two of the main body 31 and one or two protrusions 32. In this case, it is possible to prevent heat transfer concentration in the main body 31, prevent the air flow path (air passage) from being blocked by frost, and suppress a decrease in the brazing strength of the main body 31.

The main body 31 also has a main body bent portion 31b that is adjacent to the protrusion bent portion 32b in the third direction D3 and adjacent to the main body base surface 31a in the second direction D2. The main body bent portion 31b is bent in the first direction D1 relative to the main body base surface 31a to form a space (second space portion G2) through which air flows between the main body bent portion 31b and the flat portion 21 of the flat tube 20.

As a result, air that flows in the third direction D3 and reaches the end of the flat tube 20 (i.e., the curved portion 22 in FIG. 5) flows along the surface of the flat portion 21 of the flat tube 20 in the second space G2 without being blocked by the weaving of an outer fin as in the conventional art. This makes it possible to suppress air stagnation near the end of the flat tube 20 in the third direction D3 (the curved portion 22 in FIG. 5).

The bending direction of the protrusion bend 32b relative to the protrusion base surface 32a is opposite to the bending direction of the main body bend 31b relative to the main body base surface 31a. A cut 30a is formed at the boundary between the protrusion bend 32b and the main body bend 31b (boundary BL in FIG. 18).

This allows air to flow easily through the protrusion bend 32b, which forms a valley shape in the protrusion 32, and allows the air flowing through the protrusion bend 32b to flow along the flat portion 21, which is the surface of the flat tube 20, directly (i.e., without going through the outer fin 30) for efficient heat exchange.

The refrigeration cycle device 100 according to the first embodiment is equipped with a refrigerant circuit 100c in which a heat exchanger 101, a compressor 102, a flow switching device 103, an indoor heat exchanger 104, and a throttling device 105 are connected by refrigerant pipes. This improves the performance of the refrigeration cycle device 100.

The refrigeration cycle system according to the first embodiment is equipped with a refrigerant circuit 100c in which a heat exchanger 101, a compressor 102, a flow path switching device 103, an indoor heat exchanger 104, and a throttling device 105 are connected by refrigerant pipes, and a control device 108 that controls the frequency of the compressor 102, the switching of the flow path switching device 103, and the opening degree of the throttling device 105. By being equipped with the above-mentioned heat exchanger 101, the refrigeration cycle system can suppress the occurrence of abnormalities due to frosting in the heat exchanger 101 and the deterioration of heat exchange performance compared to the conventional system, thereby improving reliability.

Embodiment 2.
FIG. 8 is a perspective view showing the configuration of the main part of the heat exchanger 101 according to the second embodiment. FIG. 9 is a B-B cross-sectional view of one heat exchange member 10 arranged on the leftmost side of the main part shown in FIG. 8. FIG. 10 is a C-C cross-sectional view of one heat exchange member 10 arranged on the leftmost side of the main part shown in FIG. 8. FIG. 11 is a D-D cross-sectional view of two heat exchange members 10 arranged on the leftmost side of the main part shown in FIG. 8. FIG. 12 is an E-E cross-sectional view of two heat exchange members 10 arranged on the leftmost side of the main part shown in FIG. 8. The configuration of the heat exchange member 10 of the second embodiment will be described below, focusing on the differences from the first embodiment.

In embodiment 2, as shown in Figures 8, 11, and 12, in the heat exchange member 10, the bending direction of the main body bent portion 31b relative to the main body base surface 31a and the bending direction of the protrusion bent portion 32b relative to the protrusion base surface 32a are in the same direction as the first direction D1. Specifically, the main body bent portion 31b is bent in the negative direction of the first direction D1 (leftward in Figure 11) relative to the main body base surface 31a, and the protrusion bent portion 32b is bent in the negative direction of the first direction D1 (leftward in Figure 12) relative to the protrusion base surface 32a.

As shown in Figures 8 to 10 and 12, in the second embodiment, the portion of the outer fin 30 where the heat transfer promotion structure 33 is provided is different from that in the first embodiment. Specifically, in each of the windward protrusion 32 and the leeward protrusion 32, the heat transfer promotion structure 33a is formed on the protrusion base surface 32a, and the heat transfer promotion structure 33b is formed on the protrusion bend 32b.

As shown in Figures 11 and 12, similar to the first embodiment, the width a in the second direction D2 of the base surface (main body base surface 31a and protrusion base surface 32a) is narrower than the width b in the second direction D2 of the bent portion (main body bent portion 31b and protrusion bent portion 32b). Note that in the outer fin 30, the width a in the second direction D2 of the base surface may be narrower, wider, or the same as the width b in the second direction D2 of the bent portion.

As shown in FIG. 9, the heat transfer promotion structure 33a of the protrusion base surface 32a is composed of one heat transfer promotion part or a plurality of heat transfer promotion parts (e.g., heat transfer promotion parts 33a1, 33a2, and 33a3, etc.) arranged in the third direction D3. Also, as shown in FIG. 10, the heat transfer promotion structure 33a of the protrusion bend part 32b is composed of one heat transfer promotion part 33b0 or a plurality of heat transfer promotion parts (e.g., heat transfer promotion parts 33b1, 33b2, and 33b3, etc.) arranged in the third direction D3. In FIG. 9 to FIG. 12, the heat transfer promotion structure 33a is a plurality of louvers formed on the protrusion base surface 32a (see FIG. 9 and FIG. 12), and the heat transfer promotion structure 33b is a plurality of slits formed on the protrusion bend part 32b (see FIG. 10 and FIG. 12).

Here, the slits, which are heat transfer promoting portions, are openings that penetrate the plate-like member that constitutes the outer fin 30 (particularly the protruding portion bent portion 32b in FIG. 10). In FIG. 10 and FIG. 12, the portion of the plate-like member that forms the slits of the protruding portion bent portion 32b constitutes an anti-bending portion 33x that is bent in the opposite direction to the bending direction of the protruding portion bent portion 32b (to the right in FIG. 12). In other words, the anti-bending portion 33x is separated from the protruding portion bent portion 32b on both sides in the third direction D3, and is connected to the protruding portion bent portion 32b on both sides in the second direction D2. By forming the slits while leaving the anti-bending portion 33x, the fin area can be secured.

In the second embodiment, the heat transfer promotion structure 33 is provided on the protrusion base surface 32a, and the leading edge effect acts on the protrusion base surface 32a and the second connection portion 32c on the leeward side, promoting heat transfer. Also, in FIG. 8, the slit extends to the second connection portion 32c in the protrusion bend portion 32b, improving drainage performance. Also, when the heat transfer promotion structure 33 is provided on the second connection portion 32c, the heat transfer performance is improved by having the heat transfer promotion structure 33 in an area with high fin efficiency. In the configuration in FIG. 8, in which the heat transfer promotion structure 33 is provided only on the protrusion portion 32 in the outer fin 30, it is possible to prevent heat transfer concentration in the main body portion 31 and to prevent the air flow path (air passage) from being blocked by frost, and also to suppress a decrease in the brazing strength of the main body portion 31.

In addition, a slit (or a slit and an inverted bend 33x) may be provided on the protrusion base surface 32a as the heat transfer promotion structure 33a, and a louver may be provided on the protrusion bend 32b as the heat transfer promotion structure 33b.

Furthermore, the locations where the heat transfer promotion structure 33 is provided on the outer fin 30 are not limited to the above locations. For example, the heat transfer promotion structure 33 may be provided on only one of the protruding portions 32 on the windward side and the leeward side. For example, the heat transfer promotion structure 33 may be provided on the main body portion 31 of the outer fin 30 in addition to the above locations. For example, the heat transfer promotion structure 33 may be provided symmetrically in the third direction D3 (front-rear direction) on the outer fin 30. The protruding portion 32 may be provided on only one of the windward side and the leeward side of the flat tube 20.

As described above, in the heat exchanger 101 according to the second embodiment, as in the first embodiment, each protrusion 32 of the outer fin 30 has a shape having peaks and valleys, and the protrusion base surface 32a of each protrusion 32 is disposed on the same imaginary plane as the main body base surface 31a. Therefore, in the heat exchanger 101 according to the second embodiment, as in the first embodiment, the development of the temperature boundary layer of the airflow is suppressed more than in the conventional case, so that the heat transfer promotion structure 33 can fully function and the heat transfer promotion effect can be fully obtained.

Furthermore, in the heat exchanger 101 according to the second embodiment, a heat transfer promotion structure 33a is formed on at least the protrusion base surface 32a of the outer fin 30. Since there is little distortion in a base surface such as the protrusion base surface 32a during manufacturing, the heat transfer promotion structure 33 is easy to create. Therefore, when the heat transfer promotion structure 33a is provided on the protrusion base surface 32a, the heat transfer promotion effect is obtained as designed, improving manufacturability and performance.

Embodiment 3.
Fig. 13 is a perspective view showing a configuration of a main part of a heat exchanger 101 according to embodiment 3. As shown in Fig. 13, in embodiment 3, the width a in the second direction D2 of the base surface (main body base surface 31a and protrusion base surface 32a) is made wider than the width b in the second direction D2 of the bent portion (main body bent portion 31b and protrusion bent portion 32b).

Then, a heat transfer promotion structure 33a is provided on the protrusion base surface 32a of the protrusion 32 in the outer fin 30. In FIG. 13, the heat transfer promotion structure 33a is a plurality of louvers formed on the protrusion base surface 32a. Note that FIG. 13 illustrates a case in which the heat transfer promotion structure 33a is provided only on the protrusion base surface 32a in the outer fin 30, but for example, a heat transfer promotion structure 33b such as a slit as shown in embodiment 2 may be provided on the protrusion bend 32b.

In the protrusion 32 of the outer fin 30, when the heat transfer promotion structure 33a (louver) is provided on the wider of the protrusion bend 32b and the protrusion base surface 32a, the heat transfer promotion structure 33a can be provided over a wider area than when a louver is provided on the protrusion bend 32b, thereby enhancing the heat transfer promotion effect. Also, since the heat transfer promotion structure 33a is provided on the protrusion base surface 32a, which has a wider width a in the second direction D2 than in the second embodiment, the heat transfer promotion structure 33a is easier to make, improving manufacturability.

In FIG. 13, a heat transfer promotion structure 33a is formed on the protrusion base surface 32a from its upper end to its lower end, and the width La of the heat transfer promotion structure 33a in the second direction D2 is approximately the same as the width a of the protrusion base surface 32a. When the heat transfer promotion structure 33a is provided in this manner, a heat transfer promotion effect is achieved due to the leading edge effect. Note that the width La of the heat transfer promotion structure 33a in the second direction D2 may be any width as long as it is within the width a of the protrusion base surface 32a.

In addition, in the third embodiment, in the heat exchange member 10, the bending direction of the main body bent portion 31b relative to the main body base surface 31a and the bending direction of the protrusion bent portion 32b relative to the protrusion base surface 32a are opposite to each other. Therefore, in the plate-like member constituting the outer fin 30, a cut 30a is formed at the boundary between the main body bent portion 31b and the protrusion bent portion 32b.

FIG. 14 is a perspective view showing a first modified example of the main parts of the heat exchanger 101 according to embodiment 3. In the first modified example shown in FIG. 14, the width La of the heat transfer promotion structure 33a in the second direction D2 is narrower than the width a of the protrusion base surface 32a, and the heat transfer promotion structure 33a is formed only in the center of the protrusion base surface 32a, leaving its upper and lower ends. As in this first modified example, when the width La of the heat transfer promotion structure 33a in the second direction D2 is narrower than the width a of the protrusion base surface 32a, the fin efficiency increases, and there is a heat transfer promotion effect due to the improved fin efficiency.

FIG. 15 is a perspective view showing a second modified example of the main part of the heat exchanger 101 according to the third embodiment. In the second modified example shown in FIG. 15, the heat transfer promotion structure 33a includes heat transfer promotion parts (e.g., heat transfer promotion parts 33a1, 33a2, and 33a3) that are positioned differently in the second direction D2. The heat transfer promotion parts 33a1, 33a2, 33a3, and 33a4 are shifted in the second direction D2 and arranged in a wavy or stepped pattern to form the heat transfer promotion structure 33a. In FIG. 15, the heat transfer promotion structure 33a is a plurality of louvers formed on the protrusion base surface 32a.

In this way, by arranging the multiple louvers in a staggered manner in the second direction D2, the effect of blocking the air passage due to frost formation in the center of the louvers is reduced, and ventilation resistance is reduced. This improves heat transfer performance.

FIG. 16 is a perspective view showing a third modified example of the main part of the heat exchanger 101 according to the third embodiment. In the third modified example shown in FIG. 16, the heat transfer promotion structure 33a includes heat transfer promotion parts (heat transfer promotion parts 33a1, 33a2, 33a3, 33a4, and 33a5) having different widths W in the third direction D3. Specifically, the heat transfer promotion parts 33a1, 33a2, 33a3, 33a4, and 33a5 arranged in the third direction D3 on the protrusion base surface 32a of the protrusion 32 are configured so that the closer to the main body base surface 31a, the narrower the width W in the third direction D3. In FIG. 16, the heat transfer promotion structure 33a is a plurality of louvers formed on the protrusion base surface 32a.

As described above, by varying the width W in the third direction D3 of the multiple heat transfer promotion parts that make up the heat transfer promotion structure 33 in the third direction D3, the number of cuts in the outer fin 30 in the part far from the flat tubes 20 can be reduced. This makes it possible to suppress the deterioration of fin efficiency that occurs in the part of the outer fin 30 far from the flat tubes 20, and promotes heat transfer.

FIG. 17 is a perspective view showing a fourth modified example of the main part of the heat exchanger 101 according to embodiment 3. In the fourth modified example shown in FIG. 17, the heat transfer promotion structure 33a has a plurality of heat transfer promotion sections (e.g., a plurality of louvers) arranged in a plurality of rows in the second direction D2. In other words, in the fourth modified example, each of the plurality of heat transfer promotion sections arranged in the third direction D3 shown in FIG. 13 or 14 is divided into a plurality of heat transfer promotion sections in the second direction D2.

As described above, by arranging the multiple heat transfer promotion parts that make up the heat transfer promotion structure 33a in multiple rows in the second direction D2, the fin efficiency is increased and heat transfer is promoted, and the ventilation resistance is reduced by increasing the number of air (wind) passage paths.

Note that while FIG. 17 shows an example in which multiple heat transfer promotion parts are arranged in two rows in the second direction D2, the number of rows is not limited to two and may be three or more. Furthermore, the arrangement of multiple heat transfer promotion parts is not limited to a checkerboard arrangement as shown in FIG. 17, and may be, for example, a wave-shaped arrangement or a stepped arrangement. In other words, the multiple row configuration of the fourth modified example in which the heat transfer promotion parts shown in FIG. 17 are divided in the second direction D2 can also be applied to the second modified example shown in FIG. 15. Furthermore, the multiple row configuration of the fourth modified example may be applied to the third modified example shown in FIG. 16.

18 is a perspective view showing a fifth modified example of the main part of the heat exchanger 101 according to the third embodiment. In each of the examples of FIGS. 13 to 17, the heat transfer promotion structure 33a is provided in both the windward and leeward protrusions 32 up to the vicinity of the end of the flat tube 20 in the third direction D3, that is, up to the vicinity of the boundary BL (see FIG. 18) with the main body 31 in the protrusion 32. In the fifth modified example shown in FIG. 18, at least the leeward protrusion 32 of the windward and leeward protrusions 32 has a boundary side flat portion 34 on the side of the boundary BL (see FIG. 18) with the main body 31 where the heat transfer promotion structure 33a is not provided. In other words, the heat transfer promotion structure 33a is not provided in the protrusion 32 of the outer fin 30 in the part located immediately behind the flat tube 20 (downstream in the air flow direction).

As described above, by providing the boundary side flat portion 34 on the protruding portion 32 of the outer fin 30 immediately behind the flat tube 20, the boundary side flat portion 34 without the heat transfer promotion structure 33a is disposed in the dead water area formed downstream of the flat tube 20. This reduces the ventilation resistance in the dead water area where air tends to stagnate, and also promotes heat transfer because the fin efficiency increases due to the reduced number of cuts.

As described above, in the heat exchanger 101 according to the third embodiment, as in the first embodiment, each protrusion 32 of the outer fin 30 has a shape having peaks and valleys, and the protrusion base surface 32a of each protrusion 32 is disposed on the same imaginary plane as the main body base surface 31a. Therefore, in the heat exchanger 101 according to the third embodiment, as in the first embodiment, the development of the temperature boundary layer of the airflow is suppressed more than in the conventional case, so that the heat transfer promotion structure 33a can fully function and the heat transfer promotion effect can be fully obtained.

In addition, in the heat exchanger 101 according to the third embodiment, the protrusion base surface 32a and the protrusion bend 32b are provided such that the width a of the protrusion base surface 32a is wider than the width b of the protrusion bend 32b in the second direction D2. In addition, the protrusion base surface 32a of the protrusion 32 is provided with a heat transfer promotion structure 33a.

As a result, the heat transfer promotion structure 33 is provided on the protrusion base surface 32a, which is flatter and wider than the protrusion bend 32b, making it easier to create the heat transfer promotion structure 33a, achieving the designed heat transfer promotion effect, and improving manufacturability and performance.

Furthermore, the heat transfer promotion structure 33a is provided on the protrusion base surface 32a at a distance from both ends of the protrusion base surface 32a in the second direction D2. As a result, the width La of the heat transfer promotion structure 33a in the second direction D2 is narrower than the width a of the protrusion base surface 32a (see FIG. 14), improving the fin efficiency and providing a heat transfer promotion effect due to the improved fin efficiency.

Embodiment 4.
Fig. 19 is a perspective view showing a configuration of a heat exchange member 10 in a heat exchanger 101 according to embodiment 4. Fig. 20 is an F-F cross-sectional view of the heat exchange member 10 in Fig. 19. In the above-mentioned embodiment 3 (see Figs. 13 to 18), the heat transfer promotion structure 33a was provided on the protruding portion 32 of the outer fin 30. In this embodiment 4, as shown in Fig. 19, the heat transfer promotion structure 33c is provided on the first connection portion 31c of the main body portion 31 arranged between the flat tubes 20. In Figs. 19 and 20, the heat transfer promotion structure 33c is a plurality of louvers formed on the first connection portion 31c.

Note that while Figures 19 and 20 show a case in which the heat transfer promotion structure 33c is provided only on the first connection portion 31c of the outer fin 30, the heat transfer promotion structures 33a and 33b may also be provided on the protrusion 32, for example, as shown in embodiment 2 or 3.

In the fourth embodiment, the heat transfer promotion structure 33c is formed in the first connection portion 31c, and thus the heat transfer performance is improved by having the heat transfer promotion structure 33c in an area with high fin efficiency. In addition, the heat transfer promotion structure 33c is provided in the main body portion 31, and thus the drainage performance between the flat tubes 20 and the outer fins 30 is improved.

19 and 20, the width a of the base surface (main body base surface 31a and protrusion base surface 32a) in the second direction D2 is wider than the width b of the bent portion (main body bent portion 31b and protrusion bent portion 32b) in the second direction D2. The width a of the base surface in the second direction D2 may be narrower than or the same as the width b of the bent portion in the second direction D2.

In addition, in the fourth embodiment, the width b1 of the first central portion 31d in the main body bent portion 31b in the second direction D2 is narrower than the width b2 of the second central portion 32d in the protruding portion bent portion 32b. As a result, the proportion of the main body bent portion 31b occupied by the first connection portion 31c is greater than the proportion of the protruding portion bent portion 32b occupied by the second connection portion 32c. And, the area occupied by the first connection portion 31c in the main body bent portion 31b is greater than the area occupied by the first central portion 31d in the main body bent portion 31b.

As described above, by forming the heat transfer promotion structure 33c in the first connection portion 31c, which has a larger occupancy area than the first central portion 31d in the main body bent portion 31b of the main body portion 31, the range in which the heat transfer promotion structure 33c is formed in the main body bent portion 31b can be made wider.

As described above, in the heat exchanger 101 according to embodiment 4, similar to embodiment 1, each protrusion 32 of the outer fin 30 has a shape having peaks and valleys, and the protrusion base surface 32a of each protrusion 32 is disposed on the same imaginary plane as the main body base surface 31a. Therefore, in the heat exchanger 101 according to embodiment 4, similar to embodiment 1, the development of the temperature boundary layer of the airflow is suppressed more than in the conventional case, so that the heat transfer promotion structure 33d can fully function and the heat transfer promotion effect can be fully obtained.

Furthermore, in the heat exchanger 101 according to the fourth embodiment, at least the main body portion 31 of the outer fin 30 is formed with a heat transfer promotion structure 33c. This improves the drainage performance between the flat tubes 20 and the outer fin 30.

The main body bent portion 31b also has an inclined portion (first connection portion 31c) that extends from the main body base surface 31a in the first direction D1. A heat transfer promotion structure 33c is provided on the inclined portion of the main body bent portion 31b. As a result, by having the heat transfer promotion structure 33c in an area with high fin efficiency, the heat transfer performance is improved.

Embodiment 5.
Fig. 21 is a perspective view showing a configuration of a main part of a heat exchanger 101 according to embodiment 5. In embodiment 5 shown in Fig. 21, a heat transfer promotion structure 33d is provided at the second connection portion 32c of the protruding portion 32 of the outer fin 30. In Fig. 21, the heat transfer promotion structure 33d is a plurality of louvers. Also, in Fig. 21, the heat transfer promotion structure 33d is provided mainly at the second connection portion 32c of the protruding portion 32 of the outer fin 30, and a part of the heat transfer promotion structure 33d is provided so as to protrude onto the protruding portion base surface 32a in the second direction D2.

FIG. 21 illustrates a case in which the heat transfer promotion structure 33d is provided only on the second connection portion 32c and the protrusion base surface 32a of the protrusion 32 in the outer fin 30. However, in addition to providing the heat transfer promotion structure 33d on the second connection portion 32c and the protrusion base surface 32a, the heat transfer promotion structure 33b (see FIG. 10) as shown in embodiment 2 may also be provided on the second central portion 32d of the protrusion bend portion 32b, for example. Alternatively, in addition to providing the heat transfer promotion structure 33d on the second connection portion 32c and the protrusion base surface 32a of the protrusion 32, the heat transfer promotion structure 33c (see FIG. 20) as shown in embodiment 4 may also be provided on the main body portion 31, for example.

In embodiment 5, the heat transfer promotion structure 33d is formed on the second connection portion 32c, which is an inclined surface of the protrusion 32, improving the drainage performance of the outer fin 30.

In FIG. 21, the width a in the second direction D2 of the base surface (main body base surface 31a and protrusion base surface 32a) is wider than the width b in the second direction D2 of the bent portion (main body bent portion 31b and protrusion bent portion 32b). Note that the width a in the second direction D2 of the base surface may be narrower than or the same as the width b in the second direction D2 of the bent portion.

In addition, in the fifth embodiment, the width b12 of the second central portion 32d of the protruding portion bent portion 32b in the second direction D2 is narrower than the width b11 of the first central portion 31d of the main body bent portion 31b. As a result, the proportion of the protruding portion bent portion 32b occupied by the second connecting portion 32c is greater than the proportion of the main body bent portion 31b occupied by the first connecting portion 31c. And, the area occupied by the second connecting portion 32c in the protruding portion bent portion 32b is greater than the area occupied by the second central portion 32d in the protruding portion bent portion 32b.

As described above, by forming the heat transfer promotion structure 33d in the second connection portion 32c, which has a larger occupancy area than the second central portion 32d in the protrusion bend portion 32b of the protrusion 32, the range in which the heat transfer promotion structure 33d is formed in the protrusion bend portion 32b can be widened.

As described above, in the heat exchanger 101 according to embodiment 5, similar to embodiment 1, each protrusion 32 of the outer fin 30 has a shape having peaks and valleys, and the protrusion base surface 32a of each protrusion 32 is disposed on the same imaginary plane as the main body base surface 31a. Therefore, in the heat exchanger 101 according to embodiment 5, similar to embodiment 1, the development of the temperature boundary layer of the airflow is suppressed more than in the conventional case, so that the heat transfer promotion structure 33d can fully function and the heat transfer promotion effect can be fully obtained.

In addition, in the heat exchanger 101 according to embodiment 5, the protrusion bend 32b has an inclined portion (second connection portion 32c) that extends from the protrusion base surface 32a at an angle in the first direction D1. A heat transfer promotion structure 33d is formed on this inclined portion of the protrusion bend 32b. This allows water generated on the surfaces of the outer fin 30 and the flat tubes 20 to be drained via the heat transfer promotion structure 33d, improving the drainage performance of the outer fin 30.

10 heat exchange member, 13a end, 13b end, 20 flat tube, 21 flat portion, 22 curved portion, 23 refrigerant flow path, 30 outer fin, 30a cut, 31 main body, 31a main body base surface, 31b main body bent portion, 31c first connection portion, 31d first central portion, 32 protrusion, 32a protrusion base surface, 32b protrusion bent portion, 32c second connection portion, 32cr folded structure, 32d second central portion, 33 heat transfer promotion structure, 33a heat transfer promotion structure, 33a1 heat transfer promotion portion, 33a2 heat transfer promotion portion, 33a3 heat transfer promotion portion, 33a4 heat transfer promotion portion, 33a5 heat transfer promotion portion, 33b heat transfer promotion structure, 33b0 heat transfer promotion part, 33b1 heat transfer promotion part, 33b2 heat transfer promotion part, 33c heat transfer promotion structure, 33d heat transfer promotion structure, 33x anti-bending part, 34 boundary side flat part, 40 first header, 41 refrigerant flow port, 50 second header, 51 refrigerant flow port, 100 refrigeration cycle device, 100A outdoor unit, 100B indoor unit, 100c refrigerant circuit, 101 heat exchanger, 102 compressor, 103 flow path switching device, 104 indoor heat exchanger, 105 throttling device, 106 indoor fan, 107 outdoor fan, 108 control device, BL boundary, D1 first direction, D2 second direction, D3 third direction, G gap, G1 first space part, G2 second space part.

Claims (17)

A heat exchanger including a plurality of heat exchange elements arranged in a first direction, each of the plurality of heat exchange elements having a flat tube whose tube axis extends along a second direction intersecting the first direction and through which a refrigerant flows, and an outer fin joined to a flat portion of the flat tube, and performing heat exchange between the refrigerant and air flowing through a gap formed between adjacent heat exchange elements of the plurality of heat exchange elements,
The outer fin is formed with a heat transfer promotion structure that promotes heat transfer,
The outer fin is
A main body portion disposed between the flat tubes of the adjacent heat exchange members;
one or two protruding portions extending from the main body portion to the windward side or the leeward side in a third direction that is a direction intersecting the first direction and the second direction and is a flow direction of the air,
The main body portion has a planar main body base surface provided along the flat portion of the flat tube and joined to the flat portion,
Each of the one or two protrusions is
a protrusion base surface extending in the third direction from the body base surface and disposed on the same imaginary plane as the body base surface;
a protrusion bent portion provided adjacent to the protrusion base surface in the second direction and bent so as to protrude in the first direction relative to the protrusion base surface. the one or two protruding portions include a protruding portion extending from the main body portion to an upwind side in the third direction which is a flow direction of the air,
The heat exchanger according to claim 1 , wherein the heat transfer promotion structure is formed on the protruding portion of the outer fin that extends at least on the windward side. the one or two protruding portions include a protruding portion extending from the main body portion to a downwind side in the third direction which is a flow direction of the air,
The heat exchanger according to claim 1 or 2, wherein the heat transfer promotion structure is formed on at least the protruding portion extending to the downwind side of the outer fin. The heat exchanger according to any one of claims 1 to 3, wherein the heat transfer promotion structure is formed on at least the main body portion of the outer fin. The outer fin has a protruding portion extending from the main body portion to a windward side in the third direction and a protruding portion extending to a leeward side,
The heat exchanger according to any one of claims 1 to 4, wherein the heat transfer promotion structures are formed on the outer fins symmetrically in the third direction with respect to the tube axis. The heat exchanger according to any one of claims 1 to 5, wherein the heat transfer promotion structure is formed on at least a base surface of the protruding portion of the outer fin. the protrusion bend portion has a planar portion parallel to the main body base surface and the imaginary plane on which the protrusion base surface is disposed,
The heat exchanger according to any one of claims 1 to 6, wherein the heat transfer promotion structure is formed on at least the flat surface portion of the protruding portion bent portion of the outer fin. The protrusion bend portion has an inclined portion extending from the protrusion base surface in the first direction,
The heat exchanger according to any one of claims 1 to 7, wherein the heat transfer promotion structure is formed at least on the inclined portion of the protruding portion bent portion of the outer fin. The heat exchanger according to claim 6 , wherein the protrusion base surface and the protrusion bent portion are provided such that a width of the protrusion base surface in the second direction is wider than a width of the protrusion bent portion. The heat exchanger according to claim 6 or 9, wherein the heat transfer promotion structures are provided on the protrusion base surface away from both end portions of the protrusion base surface in the second direction. The main body portion is
The heat exchanger according to any one of claims 1 to 10, further comprising a main body bend portion that is adjacent to the protrusion bend portion in the third direction and adjacent to the main body base surface in the second direction, and is bent in the first direction relative to the main body base surface to form a space through which the air flows between the main body bend portion and the flat portion of the flat tube. a bending direction of the protrusion bending portion with respect to the protrusion base surface is opposite to a bending direction of the main body bending portion with respect to the main body base surface,
The heat exchanger according to claim 11 , wherein a cut is formed at a boundary between the protrusion bent portion and the main body bent portion. The main body bending portion has an inclined portion extending from the main body base surface in the first direction,
The heat exchanger according to claim 11 or 12, wherein the heat transfer promotion structure is formed on the inclined portion of the main body bent portion. The heat exchanger according to any one of claims 1 to 3, wherein the heat transfer promotion structure is provided only on the one or two protruding portions out of the main body portion and the one or two protruding portions. The heat exchanger according to any one of claims 1 to 14, wherein the heat transfer promotion structure is a louver or a slit. A refrigeration cycle device comprising a refrigerant circuit including the heat exchanger according to any one of claims 1 to 15, a compressor, a flow switching device, an indoor heat exchanger, and a throttling device, all connected by a refrigerant pipe. A refrigerant circuit comprising the heat exchanger according to any one of claims 1 to 15, a compressor, a flow switching device, an indoor heat exchanger, and a throttling device connected by a refrigerant pipe;
A refrigeration cycle system comprising a control device that controls a frequency of the compressor, switching of the flow path switching device, and an opening degree of the throttling device.

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