JP7037090B2 - Heat exchanger - Google Patents

Description

The present disclosure relates to heat exchangers, in particular to heat exchangers that do not use heat transfer fins.

Conventionally, a heat exchanger having a header and a heat transfer flat tube connected to the header and not using heat transfer fins is known. For example, Patent Document 1 (International Publication No. 2005/073655) discloses a heat exchanger having a straight tubular header.

However, in the actual application situation, when the heat exchanger is viewed along the extending direction of the heat transfer flat tube, for example, the heat exchanger in which the heat transfer flat tube is arranged in an L-shape or a U-shape, in other words. For example, a heat exchanger having a curved portion in the header may be required. When an attempt is made to realize a heat exchanger having such a structure by bending the header of the heat exchanger disclosed in, for example, Patent Document 1 (International Publication No. 2005/073655), heat transfer with the header at the curved portion. Damage to the brazed part with the flat tube may occur. When the heat transfer flat tube is not provided in the curved portion, such damage can be avoided, but in this case, since the curved portion of the header does not contribute to heat exchange, the heat exchanger tends to be large.

It is an object of the present disclosure to provide a compact and high-performance heat exchanger in which a curved portion is provided in a header.

The heat exchanger according to the first aspect includes a header and a plurality of heat transfer flat tubes. The header includes at least a first straight line portion, a second straight line portion, and a curved portion. The first straight line portion extends in the first direction. The second straight line portion extends in the second direction intersecting the first direction. The curved portion connects between the first straight line portion and the second straight line portion. Each of the plurality of heat transfer flat tubes is inserted into an opening formed in the header and connected to the header. The heat transfer flat tube includes a curved flat tube inserted and fixed in an opening provided in the curved portion. The longitudinal direction of the cross section of the curved flat tube is inserted into the longitudinal direction of the cross section of the heat transfer flat tube inserted and fixed in the opening provided in the first straight section and the opening provided in the second straight section. The heat transfer flat tube fixed in place is inclined with respect to each of the longitudinal directions of the cross section.

In the heat exchanger according to the first aspect, since the heat transfer flat tube is also arranged in the curved portion, the header has a shape having the curved portion, and a compact and high-performance heat exchanger can be realized.

The heat exchanger according to the second aspect is the heat exchanger according to the first aspect, and the size of the outer periphery of the connection portion of each heat transfer flat tube is larger than the size of the outer periphery other than the connection portion. .. The connection portion is a portion of each heat transfer flat tube that is inserted and fixed in the opening of the header.

In the heat exchanger according to the second aspect, by forming a large outer periphery of the connection portion of the heat transfer flat tube with the header, a relatively large brazing allowance can be secured between the header and the heat transfer flat tube, and the header and the heat transfer can be secured. It is easy to secure the strength of the connection point with the heat flat tube.

Further, by forming a large outer circumference of the connection portion with the header of the heat transfer flat tube and using the connection portion as a spacer, it is easy to arrange the heat transfer flat tubes at appropriate intervals.

The heat exchanger according to the third aspect is the heat exchanger according to the second aspect, and is a heat transfer flat tube inserted and fixed in the openings provided in the first straight line portion and the second straight line portion. The width of the connection portion in the direction orthogonal to the longitudinal direction of the cross section is uniform.

In the heat exchanger according to the third aspect, since the shape of the connection portion of the heat transfer flat tube connected to the straight portion of the header is simple, the heat transfer flat tube connected to the straight portion of the header is relatively manufactured. It's easy.

The heat exchanger according to the fourth aspect is the heat exchanger according to the second aspect or the third aspect, and the connection portion of the curved flat tube is curved with the first end portion arranged on the inner edge side of the curved portion. It extends along the longitudinal direction of the cross section of the curved flat tube between the second end portion arranged on the outer edge side of the portion. The width of the connecting portion of the curved flat pipe in the direction orthogonal to the longitudinal direction of the curved portion flat pipe at the second end is larger than the width in the direction orthogonal to the longitudinal direction of the curved portion flat pipe at the first end. Is also wide.

In the heat exchanger according to the fourth aspect, the width of the connecting portion of the curved portion flat tube connected to the curved portion of the header is wide at the second end portion on the outer edge side of the curved portion, and the first on the inner edge side of the curved portion. Thin at the edges. Therefore, the outer shape of the connecting portion of the curved portion flat tube can be made to correspond to the shape of the opening of the curved portion of the header bent in advance in the curved portion. Therefore, it is possible to easily manufacture a heat exchanger in which the heat transfer flat tube is also arranged in the curved portion.

The heat exchanger according to the fifth aspect is the heat exchanger according to the fourth aspect, and the cross-sectional shape of the connecting portion of the curved flat tube has a width in a direction orthogonal to the longitudinal direction of the cross section of the curved flat tube. It is a wedge shape that gradually widens from the first end to the second end.

In the heat exchanger according to the fifth aspect, the cross-sectional shape of the connecting portion of the curved portion flat tube connected to the curved portion of the header is a wedge shape that widens from the first end portion to the second end portion. Therefore, it is easy to make the shape of the outer shape of the connecting portion of the curved portion flat tube correspond to the shape of the opening of the curved portion of the header bent in advance in the curved portion. Therefore, it is possible to easily manufacture a heat exchanger in which the heat transfer flat tube is also arranged in the curved portion.

The heat exchanger according to the sixth aspect is the heat exchanger according to the fourth aspect or the fifth aspect, and the cross-sectional shape of the connecting portion of the curved portion flat tube is on the inner edge side of the curved portion and the outer edge side of the curved portion. Includes curved parts. The curvature of the curved portion on the inner edge side of the curved portion is larger than the curvature of the curved portion on the outer edge side of the curved portion.

By making the cross-sectional shape of the connecting portion of the curved flat tube such a shape, it is possible to make the connecting portion of the curved flat tube correspond to the shape of the opening of the curved portion of the header bent in advance in the curved portion. It's easy. Therefore, it is possible to easily manufacture a heat source heat exchanger in which a heat transfer flat tube is also arranged in the curved portion.

The heat exchanger according to the seventh aspect is the heat exchanger according to any one of the fourth aspect to the sixth aspect, and when the cross section of the connection portion of the curved portion flat tube is viewed, the connection portion of the curved portion flat tube is viewed. Is formed with a plurality of holes arranged along the longitudinal direction of the cross section. The shape of the hole closest to the inner edge of the bend is different from the shape of the hole closest to the outer edge of the bend.

It is a schematic block diagram of the refrigerating apparatus which uses the heat exchanger which concerns on one Embodiment as a heat source heat exchanger. It is a schematic perspective view of the heat source heat exchanger of FIG. An example of another shape of a heat source heat exchanger. 2 is a schematic cross-sectional view of the main body of the heat transfer flat tube of the heat source heat exchanger of FIG. 2. 2 is a schematic side view of the heat transfer flat tube of the heat source heat exchanger of FIG. 2 as viewed along the longitudinal direction of the cross section. FIG. 3 is a schematic cross-sectional view taken along the line VV of the heat source heat exchanger of FIG. FIG. 2 is a partially exploded perspective view of the liquid header of the heat source heat exchanger and the heat transfer flat tube, and the connection portion of the upper part of the heat transfer flat tube is not shown. It is a schematic plan view around the curved portion of the liquid header of the heat source heat exchanger of FIG. It is a figure which shows the outline of the connection part of the heat transfer flat tube connected to the opening around the curved part of the liquid header of the heat source heat exchanger of FIG. is doing. It is a schematic perspective view around the connection part of the heat transfer flat tube connected to the opening of the curved part of the liquid header of the heat source heat exchanger of FIG. FIG. 2 is a schematic cross-sectional view of a connection portion of a heat transfer flat tube connected to an opening of a curved portion of the liquid header of the heat source heat exchanger of FIG.

An embodiment of the heat exchanger of the present disclosure will be described with reference to the drawings. In the drawings, the same or similar members are designated by the same reference numerals across a plurality of drawings.

The heat source heat exchanger 50 and the air conditioner 100 including the heat source heat exchanger 50 according to the embodiment of the heat exchanger of the present disclosure will be described.

In this specification, the heat exchanger of the present disclosure will be described by exemplifying the case where the heat exchanger of the present disclosure is used as the heat source heat exchanger of the air conditioner 100, but the use of the heat exchanger of the present disclosure will be described. Is not limited to the heat source heat exchanger of the air conditioner. For example, the heat exchanger of the present disclosure may be used as a heat source heat exchanger for a refrigerating cycle device other than an air conditioner, such as a hot water supply device, a floor heating device, and a low temperature device such as a refrigerator or a freezer. Further, the use of the heat exchanger of the present disclosure is not limited to the heat source heat exchanger, and may be used for the heat exchanger used in the refrigeration cycle device (for example, the heat exchanger 32 used in the air conditioner 100 described later). ..

(1) Air-conditioning device First, the air-conditioning device 100 provided with the heat source heat exchanger 50 will be described with reference to FIG. FIG. 1 is a schematic configuration diagram of an air conditioner 100 that uses the heat exchanger of the present disclosure as a heat source heat exchanger 50.

The air conditioner 100 is an example of a steam compression type refrigeration cycle device. The air conditioner 100 uses the refrigeration cycle to cool and heat the air-conditioned space.

As shown in FIG. 1, the air conditioner 100 mainly has one heat source unit 10 and one utilization unit 30. The number of the heat source unit 10 and the utilization unit 30 is not limited to one, and the air conditioner 100 may have a plurality of heat source units 10 and / or utilization units 30.

In the air conditioner 100, the heat source unit 10 and the utilization unit 30 are connected by the gas refrigerant connecting pipe 26 and the liquid refrigerant connecting pipe 24 at the installation site of the air conditioning device 100 to form a refrigerant circuit 20 in which the refrigerant circulates. .. The air conditioner 100 of the present embodiment is a separate type air conditioner in which the heat source unit 10 and the utilization unit 30 are separate, but the air conditioner in which the heat exchanger of the present disclosure is used is used together with the heat source unit. The unit may be an integrated air conditioner housed in one casing.

In the present embodiment, the refrigerant enclosed in the refrigerant circuit 20 is an HFC refrigerant such as R32 or R410A. However, the type of the refrigerant is not limited to the HFC refrigerant, and may be, for example, an HFO refrigerant such as HFO1234yf, HFO1234ze (E), or a mixed refrigerant thereof. Further, the type of the refrigerant may be a natural refrigerant such as CO ₂ gas.

The details of the heat source unit 10 and the utilization unit 30 and the flow of the refrigerant in the refrigerant circuit 20 during the operation of the air conditioner 100 will be described below.

(1-1) Heat Source Unit The heat source unit 10 mainly includes a compressor 12, a flow direction switching mechanism 14, a heat source heat exchanger 50, an expansion mechanism 16, and a heat source fan 18 (see FIG. 1).

Further, the heat source unit 10 has a suction pipe 22a, a discharge pipe 22b, a first gas refrigerant pipe 22c, a liquid refrigerant pipe 22d, and a second gas refrigerant pipe 22e as pipes constituting a part of the refrigerant circuit 20 (FIG. 1). The suction pipe 22a connects the flow direction switching mechanism 14 and the suction port of the compressor 12. The discharge pipe 22b connects the discharge port of the compressor 12 and the flow direction switching mechanism 14. The first gas refrigerant pipe 22c connects the flow direction switching mechanism 14 and the gas header 52 described later of the heat source heat exchanger 50. The liquid refrigerant pipe 22d connects the liquid header 54, which will be described later, of the heat source heat exchanger 50, and the liquid refrigerant connecting pipe 24. The expansion mechanism 16 is provided in the liquid refrigerant pipe 22d. The second gas refrigerant pipe 22e connects the flow direction switching mechanism 14 and the gas refrigerant connecting pipe 26.

The compressor 12 is a device that sucks the low-pressure gas refrigerant in the refrigeration cycle from the suction pipe 22a, compresses it by a compression mechanism (not shown), and discharges it to the discharge pipe 22b. As the compressor 12, various types of compressors such as a rotary compressor and a scroll compressor can be used. The motor (not shown) of the compressor 12 that drives the compression mechanism is an inverter motor with a variable rotation speed. The rotation speed of the motor is appropriately controlled by a control unit of the air conditioner 100 (not shown) according to the operating state of the air conditioner 100. However, the motor of the compressor 12 may be a constant speed motor.

The flow direction switching mechanism 14 is a mechanism for switching the flow direction of the refrigerant in the refrigerant circuit 20. In the present embodiment, the flow direction switching mechanism 14 is a four-way switching valve. The flow direction switching mechanism 14 is not limited to the four-way switching valve, and may be composed of a plurality of solenoid valves and a refrigerant pipe to realize switching of the flow direction of the refrigerant as described below.

The flow direction switching mechanism 14 switches the flow direction of the refrigerant in the refrigerant circuit 20 so that the refrigerant discharged by the compressor 12 is sent to the heat source heat exchanger 50 during the cooling operation of the air conditioner 100. Specifically, during the cooling operation of the air conditioner 100, the flow direction switching mechanism 14 communicates the suction pipe 22a and the second gas refrigerant pipe 22e, and communicates the discharge pipe 22b and the first gas refrigerant pipe 22c (FIG. FIG. See the solid line in 1.).

On the other hand, the flow direction switching mechanism 14 switches the flow direction of the refrigerant in the refrigerant circuit 20 so that the refrigerant discharged by the compressor 12 is sent to the utilization heat exchanger 32 during the heating operation of the air conditioner 100. Specifically, during the heating operation of the air conditioner 100, the flow direction switching mechanism 14 communicates the suction pipe 22a and the first gas refrigerant pipe 22c, and communicates the discharge pipe 22b and the second gas refrigerant pipe 22e (FIG. FIG. See the broken line in 1.).

The heat source heat exchanger 50 is an example of the heat exchanger of the present disclosure. In the heat source heat exchanger 50, heat is exchanged between the refrigerant flowing through the heat transfer flat tube 60 described later of the heat source heat exchanger 50 and the external fluid (air in the present embodiment). During the cooling operation of the air conditioner 100, the heat source heat exchanger 50 functions as a radiator (condenser) for the refrigerant, and the refrigerant flowing through the heat transfer flat tube 60 exchanges heat with the external fluid (with respect to the external fluid). It is cooled (by dissipating heat). During the heating operation of the air conditioner 100, the heat source heat exchanger 50 functions as a refrigerant evaporator, and the refrigerant flowing through the heat transfer flat tube 60 exchanges heat with an external fluid (absorbs heat from the external fluid) and is heated. To. Details of the structure and the like of the heat source heat exchanger 50 will be described later.

The expansion mechanism 16 is a mechanism for reducing the pressure of the refrigerant. The expansion mechanism 16 of the present embodiment is an electronic expansion valve whose opening degree can be adjusted. The opening degree of the electronic expansion valve is appropriately controlled by a control unit of the air conditioner 100 (not shown) according to the operating state of the air conditioner 100. However, the expansion mechanism 16 is not limited to the electronic expansion valve, and may be a temperature automatic expansion valve using a temperature sensitive cylinder. Further, the expansion mechanism 16 is not limited to the expansion valve whose opening degree can be adjusted, and may be a capillary tube.

The heat source fan 18 is a device that promotes heat exchange between the refrigerant and air (external fluid) in the heat source heat exchanger 50 by supplying air taken in from the outside of the heat source unit 10 to the heat source heat exchanger 50. .. The heat source fan 18 flows in from an intake port (not shown) formed in the casing of the heat source unit 10 (not shown), passes through the heat source heat exchanger 50, and is an exhaust port (not shown) formed in the casing of the heat source unit 10. Generates a flow of air that blows out from (omitted). The type of fan of the heat source fan 18 may be appropriately selected. The motor (not shown) that drives the heat source fan 18 is an inverter motor with a variable rotation speed. The rotation speed of the motor is appropriately controlled according to the operating state by a control unit of an air conditioner 100 (not shown). However, the motor that drives the heat source fan 18 may be a constant speed motor.

(1-2) Utilization unit The utilization unit 30 is a unit that air-conditions the air-conditioning target space by exchanging heat between the refrigerant and the air in the air-conditioning target space. The utilization unit 30 mainly has a utilization heat exchanger 32 and a utilization fan 34 (see FIG. 1).

In the utilization heat exchanger 32, heat exchange is performed between the refrigerant flowing through the heat transfer tube (not shown) of the utilization heat exchanger 32 and the air in the air conditioning target space. The utilization heat exchanger 32 is a fin-and-tube type heat exchanger having, for example, a plurality of heat transfer tubes and a plurality of heat transfer fins attached to the heat transfer tubes. However, as described above, the finless heat exchanger (without heat transfer fins) of the present disclosure can also be used for the utilization heat exchanger 32.

The utilization heat exchanger 32 functions as a refrigerant evaporator during the cooling operation of the air conditioner 100, and the refrigerant flowing through the heat transfer tube of the utilization heat exchanger 32 exchanges heat with the air in the air conditioning target space (air conditioning target). It is heated (by absorbing heat from the air in the space). In other words, during the cooling operation of the air conditioner 100, the air in the air-conditioned space is cooled by the refrigerant flowing through the heat transfer tube of the utilization heat exchanger 32. On the other hand, the utilization heat exchanger 32 functions as a radiator (condenser) of the refrigerant during the heating operation of the air conditioning device 100, and the refrigerant flowing through the heat transfer tube of the utilization heat exchanger 32 exchanges heat with the air in the air conditioning target space. (Dissipates heat to the air in the air-conditioned space) and cools. In other words, during the heating operation of the air conditioner 100, the air in the air-conditioned space is heated by the refrigerant flowing through the heat transfer tube of the utilization heat exchanger 32.

The utilization fan 34 is a device that promotes heat exchange between the refrigerant in the utilization heat exchanger 32 and the air in the air conditioning target space by supplying the air taken in from the air conditioning target space to the utilization heat exchanger 32. The utilization fan 34 flows from the air-conditioned space through the intake port (not shown) formed in the casing (not shown) of the utilization unit 30, passes through the utilization heat exchanger 32, and is formed in the casing of the utilization unit 30. Generates an air flow that blows out from the air outlet (not shown) to the air-conditioned space. The type of fan of the fan 34 to be used may be appropriately selected. The motor (not shown) that drives the fan 34 is an inverter motor with a variable rotation speed. The rotation speed of the motor is appropriately controlled according to the operating state by a control unit of an air conditioner 100 (not shown). However, the motor that drives the utilization fan 34 may be a constant speed motor.

(1-3) Flow of Refrigerant in Air Conditioning Device In the air conditioning device 100, the refrigerant circulates in the refrigerant circuit 20 during the cooling operation and the heating operation, respectively, as shown below.

(1-3-1) During cooling operation During cooling operation, the flow direction switching mechanism 14 is in the state shown by the solid line in FIG. 1, and the discharge side of the compressor 12 communicates with the gas side of the heat source heat exchanger 50 and is compressed. The suction side of the machine 12 communicates with the gas side of the heat exchanger 32 used.

When the compressor 12 is driven in this state, the low-pressure gas refrigerant in the refrigeration cycle flowing from the suction pipe 22a is compressed by the compression mechanism of the compressor 12 to become a high-pressure gas refrigerant. The high-pressure gas refrigerant discharged by the compressor 12 flows into the heat source heat exchanger 50 via the discharge pipe 22b, the flow direction switching mechanism 14, and the first gas refrigerant pipe 22c. The high-pressure gas refrigerant is cooled and condensed by exchanging heat with the air supplied by the heat source fan 18 in the heat source heat exchanger 50, undergoes a gas-liquid two-phase state, and finally becomes a high-pressure liquid refrigerant. Become. The high-pressure liquid refrigerant flowing out of the heat source heat exchanger 50 is sent to the expansion mechanism 16. The low-pressure gas-liquid two-phase refrigerant decompressed by the expansion mechanism 16 flows through the liquid refrigerant pipe 22d and the liquid refrigerant connecting pipe 24 and flows into the liquid side of the utilization heat exchanger 32. The refrigerant flowing into the used heat exchanger 32 exchanges heat with the air in the air-conditioned space to evaporate, becomes a low-pressure gas refrigerant, and flows out from the used heat exchanger 32. The low-pressure gas refrigerant flowing out of the utilization heat exchanger 32 is sucked into the compressor 12 again via the gas refrigerant connecting pipe 26, the second gas refrigerant pipe 22e, the flow direction switching mechanism 14, and the suction pipe 22a.

(1-3-2) During heating operation During heating operation, the flow direction switching mechanism 14 is in the state shown by the broken line in FIG. 1, and the discharge side of the compressor 12 communicates with the gas side of the heat exchanger 32 and is compressed. The suction side of the machine 12 communicates with the gas side of the heat source heat exchanger 50.

When the compressor 12 is driven in this state, the low-pressure gas refrigerant in the refrigeration cycle flowing from the suction pipe 22a is compressed by the compression mechanism of the compressor 12 to become a high-pressure gas refrigerant. The high-pressure gas refrigerant discharged by the compressor 12 flows into the utilization heat exchanger 32 via the discharge pipe 22b, the flow direction switching mechanism 14, the second gas refrigerant pipe 22e, and the gas refrigerant connecting pipe 26. The high-pressure gas refrigerant is cooled and condensed by exchanging heat with the air in the air-conditioned space in the utilization heat exchanger 32 to become a high-pressure liquid refrigerant. The high-pressure liquid refrigerant flowing out of the utilization heat exchanger 32 flows through the liquid refrigerant connecting pipe 24 and the liquid refrigerant pipe 22d and is sent to the expansion mechanism 16. The high-pressure liquid refrigerant sent to the expansion mechanism 16 is depressurized as it passes through the expansion mechanism 16. The low-pressure liquid phase or gas-liquid two-phase refrigerant decompressed by the expansion mechanism 16 flows into the heat source heat exchanger 50. The refrigerant flowing into the heat source heat exchanger 50 is heated and evaporated by exchanging heat with the air supplied by the heat source fan 18, becomes a low-pressure gas refrigerant, and flows out from the heat source heat exchanger 50. The low-pressure gas refrigerant flowing out of the heat source heat exchanger 50 is sucked into the compressor 12 again via the first gas refrigerant pipe 22c, the flow direction switching mechanism 14 and the suction pipe 22a.

(2) Heat Source Heat Exchanger The heat source heat exchanger 50 will be described with reference to FIGS. 2 to 8.

FIG. 2 is a schematic perspective view of the heat source heat exchanger 50. FIG. 3 is an example of another shape of the heat source heat exchanger 50. FIG. 4a is a schematic cross-sectional view of the main body portions 62a, 64a, 66a of the heat transfer flat tube 60 of the heat source heat exchanger 50. FIG. 4b is a schematic side view of the heat transfer flat tube 60 of the heat source heat exchanger 50 as viewed along the longitudinal direction of the cross section. FIG. 5 is a schematic cross-sectional view taken along the line VV of the heat source heat exchanger 50 of FIG. FIG. 6 is a partially exploded perspective view of the liquid header 54 of the heat source heat exchanger 50 and the heat transfer flat tube 60, and the illustration of the connection portions 62b, 64b, 66b at the upper part of the heat transfer flat tube 60 is omitted. FIG. 7 is a schematic plan view of the periphery of the curved portion 54c of the liquid header 54 of the heat source heat exchanger 50. FIG. 8 is a diagram showing the outer shape of the connection portions 62b, 64b, 66b of the heat transfer flat tubes 62, 64, 66 connected to the opening 55c around the curved portion 54c of the liquid header 54 of the heat source heat exchanger 50. The outer shapes of the main bodies 62a, 64a, 66a of the heat transfer flat tube 60 are drawn together with a broken line. FIG. 9 is a schematic perspective view of the periphery of the connecting portion 66b of the curved portion flat tube 66 connected to the opening 55c of the curved portion 54c of the liquid header 54 of the heat source heat exchanger 50. FIG. 10 is a schematic cross-sectional view of the connecting portion 56 of the curved portion flat tube 66 connected to the opening 55c of the curved portion 54c of the liquid header 54 of the heat source heat exchanger 50.

2 to 10 are schematic views for explaining the features of the heat source heat exchanger 50. Therefore, FIGS. 2 to 10 do not limit the shape, size, quantity, etc. of the whole and part of the heat source heat exchanger 50.

In the following description, expressions such as up, down, left, right, front (front), and back (back) may be used to explain the direction, position, and the like. Unless otherwise specified, the directions and positions indicated by these expressions follow the arrows in the figure.

In the following description, expressions such as horizontal, vertical, parallel, vertical, and identical may be used, but these expressions do not only represent the states such as horizontal, vertical, parallel, vertical, and identical in a strict sense. , Substantially horizontal, vertical, parallel, vertical, identical, etc.

The heat source heat exchanger 50 mainly includes a gas header 52, a liquid header 54 arranged below the gas header 52, and a heat exchange unit 51 (see FIG. 2). The heat exchange unit 51 includes a plurality of heat transfer flat tubes 60. One end of each of the plurality of heat transfer flat tubes 60 is connected to the gas header 52. In this embodiment, the upper end of each of the plurality of heat transfer flat tubes 60 is connected to the gas header 52. Further, one end of each of the plurality of heat transfer flat tubes 60 is connected to the liquid header 54. In the present embodiment, the lower ends of each of the plurality of heat transfer flat tubes 60 are connected to the liquid header 54.

The heat source heat exchanger 50 is a finless heat exchanger that does not use heat transfer fins. In the heat source heat exchanger 50, heat exchange between the refrigerant and the external fluid (air in the present embodiment) supplied by the heat source fan 18 is performed mainly in the heat transfer flat tube 60.

The heat source heat exchanger 50 is made of, for example, aluminum or an aluminum alloy. However, the material of the heat source heat exchanger 50 is not limited to aluminum or an aluminum alloy, and may be made of, for example, a magnesium alloy. Further, as the material of the heat source heat exchanger 50, a material other than those illustrated may be selected.

The materials of the gas header 52, the liquid header 54, and the heat transfer flat tube 60 of the heat exchange section 51 may be different from each other. However, from the viewpoint of preventing electrolytic corrosion, it is preferable that the materials of the gas header 52, the liquid header 54, and the heat transfer flat tube 60 of the heat exchange section 51 are the same.

In the present embodiment, in the heat source heat exchanger 50, as shown in FIG. 2, the gas header 52 and the liquid header 54 each have an L-shape. However, the shapes of the headers 52 and 54 of the heat source heat exchanger 50 described in this embodiment are merely examples. For example, the shape of the header of the heat source heat exchanger 50 may be a V-shape in which two straight portions are bent so as to form an obtuse angle, as shown in FIG. Further, the shape of the header of the heat source heat exchanger 50 may be a U-shape or a quadrangular shape having two or more curved portions.

(2-1) Liquid Header The liquid header 54 is a hollow member having a space formed inside. With the heat source heat exchanger 50 installed, the liquid header 54 is arranged at the bottom (bottom) of the heat source heat exchanger 50.

The liquid header 54 is an L-shaped member in a plan view. The liquid header 54 is manufactured by bending a linear material at the curved portion 54c.

As shown in FIG. 5, the liquid header 54 of the heat source heat exchanger 50 has a first straight line portion 54a extending in the first direction, a second straight line portion 54b extending in the second direction intersecting the first direction, and a first straight line portion 54b. Includes a curved portion 54c connecting between the straight portion 54a and the second straight portion 54b. In the heat source heat exchanger 50 of the present embodiment, the second direction is orthogonal to the first direction. Hereinafter, for convenience of explanation, the following description will be given with the first direction as the left-right direction and the second direction as the front-back direction, as shown in FIG.

A plurality of openings 55 are arranged side by side along the stretching direction of the liquid header 54 (see FIG. 6). Here, the stretching direction of the liquid header 54 is a curved portion from one end of the liquid header 54 (the right end on the first straight line portion 54a side) as shown by the arrow B shown by the broken line in FIG. The direction is toward the other end of the header 54 (the lower end of the second straight line portion 54b) while changing the stretching direction in 54c. The arrow B shown in FIG. 5 is a line along the center line passing through the center in the width direction of the liquid header 54.

In the present embodiment, the opening 55 is a flat, substantially quadrangular hole whose longitudinal direction is substantially orthogonal to the stretching direction of the liquid header 54 (see FIG. 7). Specifically, the opening 55 (opening 55a) formed in the first straight line portion 54a extending in the left-right direction is a flat substantially quadrangular hole whose longitudinal direction is the front-back direction (see FIG. 7). Further, the opening 55 (opening 55b) formed in the second straight line portion 54b extending in the front-rear direction is a flat substantially quadrangular hole whose longitudinal direction is the left-right direction (see FIG. 7). The opening 55 (opening 55c) formed in the curved portion 54c is a flat, substantially quadrangular hole whose longitudinal direction intersects both the front-rear direction and the left-right direction (see FIG. 7).

As described above, the liquid header 54 is manufactured by bending a linear member having an opening 55 formed in advance at the curved portion 54c. Therefore, the widths of the openings 55a formed in the first straight line portion 54a and the openings 55b formed in the second straight line portion 54b in the directions orthogonal to the longitudinal directions of the openings 55a and 55b are substantially uniform in the width A1. On the other hand, the opening 55c of the curved portion 54c has a non-uniform width in the direction orthogonal to the longitudinal direction of the opening 55c. Specifically, the width of the curved portion 54c in the direction orthogonal to the longitudinal direction is as narrow as the width A2 on the inner edge 54c1 side of the curved portion 54c having a large curvature, and the width on the outer edge 54c2 side of the curved portion 54c having a small curvature. Wide as A3 (see Fig. 7). That is, the opening 55c of the curved portion 54c has a substantially wedge-shaped shape in which the inner edge 54c1 side of the curved portion 54c is narrow.

The function of the liquid header 54 will be described.

The liquid header 54 divides the refrigerant flowing from the liquid refrigerant pipe 22d into the plurality of heat transfer flat pipes 60, or merges the refrigerants flowing from the plurality of heat transfer flat pipes 60 and flows them into the liquid refrigerant pipe 22d. It is a member having a function. This will be described in detail.

Inside the liquid header 54, an internal space is formed in which the liquid refrigerant flows from the liquid refrigerant pipe 22d and the plurality of heat transfer flat pipes 60.

One end of each of the plurality of heat transfer flat tubes 60 of the heat exchange section 51 is connected to the liquid header 54. In particular, in the present embodiment, the lower ends of the plurality of heat transfer flat tubes 60 of the heat exchange section 51 are connected to the opening 55 of the liquid header 54. A plurality of heat transfer flat tubes 60 are connected to the liquid header 54 so that the heat transfer flat tubes 60 are lined up along the extending direction B of the liquid header 54. The plurality of heat transfer flat tubes 60 are inserted into the openings 55 formed in the liquid header 54, and are fixed by brazing, for example. By connecting the plurality of heat transfer flat tubes 60 to the liquid header 54, the refrigerant flow paths P of the plurality of heat transfer flat tubes 60, which will be described later, communicate with the internal space of the liquid header 54.

The liquid header 54 has a connecting portion 58 to which the liquid refrigerant pipe 22d is connected. The internal space of the liquid header 54 and the liquid refrigerant pipe 22d communicate with each other via the connecting portion 58.

As a result of this configuration, when the heat source heat exchanger 50 functions as a condenser, the liquid header 54 merges the liquid refrigerant flowing into the internal space from the plurality of heat transfer flat tubes 60 and joins the liquid refrigerant pipe 22d. Inflow. Further, when the heat source heat exchanger 50 functions as an evaporator, the liquid header 54 uses the liquid refrigerant or the gas-liquid two-phase refrigerant flowing into the internal space from the liquid refrigerant pipe 22d, respectively, in the plurality of heat transfer flat pipes 60. It is diverted to the refrigerant flow path P provided in.

(2-2) Gas Header The gas header 52 is a hollow member having a space formed inside. With the heat source heat exchanger 50 installed, the gas header 52 is arranged above the heat source heat exchanger 50.

The gas header 52 has a shape corresponding to the liquid header 54. Specifically, the gas header 52 is an L-shaped member in a plan view, like the liquid header 54. The gas header 52 is also manufactured by bending a linear material at a curved portion.

As shown in FIG. 2, the gas header 52 of the heat source heat exchanger 50 also has a first straight line portion 52a extending in the left-right direction, a second straight line portion 52b extending in the front-rear direction, a first straight line portion 52a, and a second straight line portion 52b. Includes a curved portion 52c that connects to and from.

The shape of the gas header 52 is substantially the same as the shape of the liquid header 54, except that an opening (not shown) into which the heat transfer flat tube 60 is inserted is formed in the lower part of the gas header 52 instead of the upper part. , A detailed description is omitted here.

The function of the gas header 52 will be described.

The gas header 52 divides the refrigerant flowing from the first gas refrigerant pipe 22c into the plurality of heat transfer flat pipes 60, or merges the refrigerants flowing in from the plurality of heat transfer flat pipes 60 and flows into the first gas refrigerant pipe 22c. It is a member having a function of making it. This will be described in detail.

Inside the gas header 52, an internal space is formed in which the refrigerant flows from the first gas refrigerant pipe 22c and the plurality of heat transfer flat pipes 60.

One end of each of the plurality of heat transfer flat tubes 60 of the heat exchange section 51 is connected to the gas header 52. In particular, in the present embodiment, the gas header 52 is connected to the upper ends of each of the plurality of heat transfer flat tubes 60 of the heat exchange section 51. A plurality of heat transfer flat tubes 60 are connected to the gas header 52 so that the heat transfer flat tubes 60 are lined up along the extending direction of the gas header 52. The plurality of heat transfer flat tubes 60 are inserted into openings (not shown) formed in the gas header 52, and are brazed and fixed, for example. By connecting the plurality of heat transfer flat pipes 60 to the gas header 52, the refrigerant flow paths P of the plurality of heat transfer flat pipes 60, which will be described later, communicate with the internal space of the gas header 52.

The gas header 52 has a connecting portion 56 to which the first gas refrigerant pipe 22c is connected. The internal space of the gas header 52 and the first gas refrigerant pipe 22c communicate with each other via the connecting portion 56.

As a result of this configuration, when the heat source heat exchanger 50 functions as a condenser, the gas header 52 transfers the refrigerant flowing into the internal space from the first gas refrigerant pipe 22c to each of the plurality of heat transfer flat pipes 60. It is diverted to the provided refrigerant flow path P. Further, when the heat source heat exchanger 50 functions as an evaporator, the gas header 52 merges the refrigerants flowing into the internal space from the plurality of heat transfer flat pipes 60 and flows them into the first gas refrigerant pipe 22c.

(2-3) Heat Exchange Unit The heat exchange unit 51 mainly includes a plurality of heat transfer flat tubes 60. The upper end of each heat transfer flat tube 60 is connected to the gas header 52, and the lower end of each heat transfer flat tube 60 is connected to the liquid header 54 (see FIG. 2).

In the following, in addition to the shape of the heat transfer flat tube 60 and the like, the contents related to the connection between each heat transfer flat tube 60 and the headers 52 and 54 will be described. The connection between the heat transfer flat tube 60 and the liquid header 54 and the connection between the heat transfer flat tube 60 and the gas header 52 are generally the same except for which upper or lower end of the heat transfer flat tube 60 is connected. The same is true. Therefore, here, the contents related to the connection between the heat transfer flat tube 60 and the liquid header 54 will be mainly described, and the contents related to the connection between the heat transfer flat tube 60 and the gas header 52 will be described in order to avoid duplication of description. Omit if not particularly necessary.

In the following description, for convenience of explanation, the heat transfer flat tube 60 is connected to the first flat tube 62 connected to the first straight portion 54a of the liquid header 54 and to the second straight portion 54b of the liquid header 54. 2 The flat tube 64 and the curved flat tube 66 connected to the curved portion 54c of the liquid header 54 may be referred to separately. Further, the first flat tube 62, the second flat tube 64, and the curved portion flat tube 66 may be collectively referred to as heat transfer flat tubes 62, 64, 66. In the present embodiment, the first flat tube 62 and the second flat tube 64 have the same shape and size, although the attachment directions to the headers 52 and 54 are different.

The heat transfer flat tube 60 of the heat exchange unit 51 extends with the vertical direction (vertical direction) as the longitudinal direction in a state where the heat source heat exchanger 50 is installed. The heat transfer flat tube 60 is formed with a refrigerant flow path P extending in the longitudinal direction. Specifically, the heat transfer flat pipe 60 is a flat multi-hole pipe in which a plurality of refrigerant flow paths P are formed, as shown in the cross-sectional view shown in FIG. 4a. With the heat source heat exchanger 50 installed, the plurality of refrigerant flow paths P of the heat transfer flat tube 60 extend along the vertical direction. The number of refrigerant flow paths P formed in each heat transfer flat tube 60 is not limited to the number of refrigerant flow paths P drawn in FIG. 4a.

Each heat transfer flat tube 62, 64, 66 includes a connection portion 62b, 64b, 66b and a main body portion 62a, 64a, 66a as shown in FIG. 4b.

The connecting portions 62b, 64b, 66b are provided at both ends (upper and lower ends) of each heat transfer flat tube 60, as shown in FIG. 4b. The connecting portions 62b, 64b, 66b are inserted into the opening of the gas header 52 (not shown) or the opening 55 of the liquid header 54, and are fixed to the headers 52, 54. Although the fixing method is not limited, the connection portions 62b, 64b, 66b are fixed to the headers 52, 54 by brazing.

The main body portions 62a, 64a, 66a are arranged between the connecting portions 62b, 64b, 66b arranged at both ends in the longitudinal direction of the heat transfer flat tube 60, as shown in FIG. 4b. In other words, the main body portions 62a, 64a, 66a are arranged at the central portion in the longitudinal direction of the heat transfer flat tube 60. The main body portions 62a, 64a, 66a are portions that mainly contribute to heat exchange of the heat source heat exchanger 50.

The size of the outer periphery of the connecting portions 62b, 64b, 66b is formed to be larger than the size of the outer periphery of the main body portions 62a, 64a, 66a. The shapes (outer shapes) of the connection portion 62b of the first flat tube 62 and the connection portion 64b of the second flat tube 64 are the same as the shapes of the main body portion 62a of the first flat tube 62 and the main body portion 64a of the second flat tube 64, respectively. It is similar. On the other hand, the shape of the connecting portion 66b of the curved portion flat tube 66 is not similar to the shape of the main body portion 66a of the curved portion flat tube 66. Details will be described later.

(2-3-1) The main bodies 62a, 64a, 66a of the main body heat transfer flat tubes 62, 64, 66 are planes orthogonal to the longitudinal direction (here, the vertical direction) of the heat transfer flat tubes 62, 64, 66. When cut in, a certain direction is defined as the longitudinal direction (hereinafter, this direction is referred to as the longitudinal direction L1 of the cross section), and the width in the direction orthogonal to the longitudinal direction L1 of the cross section is thin and has a flat cross section (see FIG. 4a). In the following description, unless otherwise specified, the expression of the cross section of the heat transfer flat tube 60 (the main bodies 62a, 64a, 66a of the heat transfer flat tubes 62, 64, 66 and the connection portions 62b, 64b, 66b) is used. It means a cross section when the heat transfer flat tube 60 is cut in a plane orthogonal to the longitudinal direction (vertical direction when the heat source heat exchanger 50 is installed).

In the cross section of the main body portions 62a, 64a, 66a of each heat transfer flat tube 60, a plurality of holes 61 forming the refrigerant flow path P are arranged side by side along the longitudinal direction L1 of the cross section as shown in FIG. 4a. Although the shape of the hole 61 is circular in the drawing, the shape of the hole 61 may be other than circular (for example, a quadrangle).

In the present embodiment, the cross sections of the main bodies 62a, 64a, 66a of the heat transfer flat tubes 62, 64, 66 have a flat substantially quadrangular shape, for example, as shown in FIG. 4a. Curved portions C1 and C2 may be provided at both ends of the main body portions 62a, 64a, 66a in the longitudinal direction L1 of the cross section as shown in FIG. 4a. The width W0 of the cross section of the main body portions 62a, 64a, 66a of each heat transfer flat tube 60 in the direction orthogonal to the cross-sectional longitudinal direction L1 is uniform (except for the curved portions C1 and C2 at both ends in the cross-sectional longitudinal direction L1). be. Note that FIG. 4a does not limit the shape of the cross section of the main body portions 62a, 64a, 66a of the heat transfer flat tube 60.

Each heat transfer flat tube 60 is attached to the liquid header 54 and the gas header 52 so that its cross-sectional longitudinal direction L1 coincides with the longitudinal direction of the opening 55 formed in the liquid header 54. In other words, the heat transfer flat tube 60 has the gas header 52 and the liquid header 54 in such a posture that the direction in which the cross-sectional longitudinal direction L1 of the heat transfer flat tube 60 extends is substantially orthogonal to the extension direction B of the opening 55 of the liquid header 54. It is attached to (see FIG. 5). In other words, the heat transfer flat tube 60 is attached to the gas header 52 and the liquid header 54 in such a posture that the direction orthogonal to the longitudinal direction L1 of the heat transfer flat tube 60 substantially coincides with the extension direction B of the liquid header 54. It is attached.

As a result of this configuration, the cross-sectional longitudinal direction L1 of the first flat tube 62 inserted and fixed in the opening 55a provided in the first straight line portion 54a of the liquid header 54 coincides with the front-rear direction. The cross-sectional longitudinal direction L1 of the second flat tube 64 inserted and fixed in the opening 55b provided in the second straight line portion 54b of the liquid header 54 coincides with the left-right direction. Further, the longitudinal direction L1 of the curved portion flat tube 66 inserted and fixed in the opening 55b provided in the curved portion 54c of the liquid header 54 is inclined in both the front-rear direction and the left-right direction. is doing.

That is, in the heat source heat exchanger 50, the section longitudinal direction L1 of the curved portion flat tube 66 inserted and fixed in the opening 55c provided in the curved portion 54c of the liquid header 54 in the heat transfer flat tube 60 is The heat transfer flat tube 60 (first flat tube 62) inserted and fixed in the opening 55a provided in the first straight portion 54a of the liquid header 54 in the longitudinal direction L1 of the cross section and the second straight portion of the liquid header 54. The heat transfer flat tube 60 (second flat tube 64) inserted and fixed in the opening 55b provided in 54b is inclined with respect to each of the cross-sectional longitudinal directions L1.

The longitudinal direction L1 of the heat transfer flat tube 60 substantially coincides with the flow direction of the air generated by the heat source fan 18 (see the arrow F shown in FIG. 5). In the present embodiment, as shown in FIG. 5, the heat source fan 18 is arranged at a position facing the front surface and the right surface of the heat source heat exchanger 50. When the heat source fan 18 is operated, air (heat source air) flows into the inside of the casing from the intake ports formed on the back surface and the left surface of the casing (not shown) of the heat source unit 10, and as shown by the arrow F, the heat source heat exchanger After passing the 50 from the rear to the front, from the left to the right, or from the left rear to the right front, the heat is blown forward from the exhaust port formed on the front surface of the casing of the heat source unit 10. By making the cross-sectional longitudinal direction L1 of the heat transfer flat tube 60 substantially coincide with the air flow direction generated by the heat source fan 18, the heat transfer extends along the cross-sectional longitudinal direction L1 while suppressing the ventilation resistance of the heat source heat exchanger 50. High heat exchange efficiency can be realized by efficiently contacting the side surface of the heat flat tube 60 with the air sent by the heat source fan 18.

Here, the cross section of the main body portion 62a of the first flat tube 62, the cross section of the main body portion 64a of the second flat tube 64, and the cross section of the main body portion 66a of the curved portion flat tube 66 are oriented in the longitudinal direction L1 of the cross section. Although they are different from each other, the shape and size of the cross section are the same.

(2-3-2) Connection portion The connection portions 62b, 64b, 66b of the heat transfer flat tubes 62, 64, 66 will be described.

Similar to the cross section of the main body portions 62a, 64a, 66a, the cross section of the connecting portions 62b, 64b, 66b of the heat transfer flat tubes 62, 64, 66 also has a certain direction as the cross section longitudinal direction and is orthogonal to the cross section longitudinal direction. It is thin and has a flat cross section (see FIG. 8). The longitudinal direction of the cross section of the connecting portions 62b, 64b, 66b of the heat transfer flat tubes 62, 64, 66 is the same as the longitudinal direction of the cross section of the main body portions 62a, 64a, 66a of the heat transfer flat tubes 60. Therefore, in the following, the longitudinal direction of the cross section of the connecting portions 62b, 64b, 66b of the heat transfer flat tube 60 is also represented as the longitudinal direction L1 of the cross section.

As shown in FIG. 6, for example, the connection portions 62b, 64b, 66b of the heat transfer flat tube 60 are formed larger than the main body portions 62a, 64a, 66a of the heat transfer flat tube 60, in other words, the heat transfer flat tube. The connection portions 62b, 64b, 66b of the 60 are expanded with respect to the main body portions 62a, 64a, 66a of the heat transfer flat tube 60.

By providing the connecting portions 62b, 64b, 66b having a larger outer circumference than the main body portions 62a, 64a, 66a of the heat transfer flat tube 60, the brazing allowance can be secured. Further, connecting portions 62b, 64b, 66b having a larger outer circumference than the main body portions 62a, 64a, 66a of the heat transfer flat tube 60 are provided, and the connecting portions 62b, 64b, 66b of the adjacent heat transfer flat tube 60 are connected to each other. By brazing to the headers 52 and 54 in a laminated state, a predetermined gap can be secured between the main bodies 62a, 64a and 66a of the adjacent heat transfer flat tubes 60. In other words, by providing connecting portions 62b, 64b, 66b having a larger outer circumference than the main bodies 62a, 64a, 66a of the heat transfer flat tube 60, between the main bodies 62a, 64a, 66a of the adjacent heat transfer flat tube 60. Distance can be managed to a predetermined distance.

Regarding the shape of the connection portion 62b, 64b, 66b of the heat transfer flat tube 60, the connection portion 62b of the first flat tube 62, the connection portion 64b of the second flat tube 64, and the connection portion 66b of the curved flat tube 66. I will explain separately.

(2-3-2-1) Shape of the connecting portion of the first flat tube and the second flat tube The cross section of the connecting portion 62b of the first flat tube 62 is the main body portion 62a of the first flat tube 62 as described above. Similar to the cross section of. Further, the cross section of the connecting portion 64b of the second flat tube 64 is similar to the cross section of the main body portion 64a of the second flat tube 64, as described above.

In short, the size of the outer circumference of the cross section of the connecting portion 62b of the first flat tube 62 is different from the size of the outer circumference of the cross section of the main body portion 62a of the first flat tube 62, but the cross section of the connecting portion 62b of the first flat tube 62. And the shape of the cross section of the main body portion 62a of the first flat tube 62 are substantially the same. Further, the size of the outer circumference of the cross section of the connecting portion 64b of the second flat tube 64 is different from the size of the outer circumference of the cross section of the main body portion 64a of the second flat tube 64, but the cross section of the connecting portion 64b of the second flat tube 64. And the shape of the cross section of the main body portion 64a of the second flat tube 64 are substantially the same.

As described above, the width of the main body portion 62a of the first flat tube 62 and the main body portion 64a of the second flat tube 64 in the direction orthogonal to the longitudinal direction L1 of the cross section is uniform at W0. Therefore, the cross-sectional length of the connecting portion 62b of the first flat tube 62 and the connecting portion 64b of the second flat tube 64, which are similar to the main body portion 62a of the first flat tube 62 and the main body portion 64a of the second flat tube 64. The width in the direction orthogonal to the direction L1 is also uniform in W1 (see FIG. 8). However, the width W1 is larger than the width W0.

The outer shape of the connecting portion 62b of the first flat tube 62 substantially matches the outer shape of the opening 55a provided in the first straight line portion 54a of the liquid header 54. More specifically, the shape of the connecting portion 62b of the first flat tube 62 is substantially similar to the shape of the opening 55a provided in the first straight line portion 54a of the liquid header 54, and the shape of the first flat tube 62 The size of the connecting portion 62b is slightly smaller than the size of the opening 55a provided in the first straight line portion 54a of the liquid header 54.

Further, the outer shape of the connecting portion 64b of the second flat tube 64 substantially matches the outer shape of the opening 55b provided in the second straight line portion 54b of the liquid header 54. More specifically, the shape of the connecting portion 64b of the second flat tube 64 is substantially similar to the shape of the opening 55b provided in the second straight line portion 54b of the liquid header 54, and the shape of the second flat tube 64 is similar to that of the opening 55b. The size of the connecting portion 64b is slightly smaller than the size of the opening 55b provided in the second straight line portion 54b of the liquid header 54.

(2-3-2-2) Shape of connection portion of curved flat tube The cross section of the connecting portion 66b of the curved flat tube 66 is similar to the cross section of the main body portion 66a of the curved flat tube 66 as described above. Not. This will be described in detail.

As described above, the width of the main body portion 66a of the curved portion flat tube 66 in the direction orthogonal to the longitudinal direction L1 of the cross section is uniform at W0.

On the other hand, the width of the connecting portion 66b of the curved portion flat pipe 66 in the direction orthogonal to the longitudinal direction L1 of the cross section is not uniform. This will be described in detail.

As shown in FIG. 8, the connecting portion 66b of the curved portion flat tube 66 is arranged on the first end portion E1 arranged on the inner edge 54c1 side of the curved portion 54c of the liquid header 54 and on the outer edge 54c2 side of the curved portion 54c. It extends between the second end portion E2 and the curved portion flat tube 66 along the longitudinal direction L1 of the cross section. The first end portion E1 here means the end portion of the connecting portion 66b of the curved portion flat tube 66 on the inner edge 54c1 side of the curved portion 54c of the liquid header 54, excluding the curved portion C1'(FIG. 8). reference). Further, the second end portion E2 here means the end portion of the connecting portion 66b of the curved portion flat tube 66 on the outer edge 54c2 side of the curved portion 54c of the liquid header 54, excluding the curved portion C2'(FIG. 8). reference). In the connecting portion 66b of the curved portion flat pipe 66, the width W3 in the direction orthogonal to the cross-sectional longitudinal direction L1 of the curved portion flat pipe 66 at the second end portion E2 is the cross-sectional length of the curved portion flat pipe 66 at the first end portion E1. It is wider than the width W2 in the direction orthogonal to the direction L1.

Preferably, the cross-sectional shape of the connecting portion 66b of the curved portion flat pipe 66 has a width in a direction orthogonal to the cross-sectional longitudinal direction L1 of the curved portion flat pipe 66 gradually increasing from the first end portion E1 to the second end portion E2. It has a wide wedge shape. In other words, the cross-sectional shape of the connecting portion 66b of the curved portion flat tube 66 is a wedge shape that gradually widens from the inner edge 54c1 side of the curved portion 54c of the liquid header 54 toward the outer edge 54c2 side of the curved portion 54c of the liquid header 54. Trapezoidal shape).

The cross-sectional shape of the connecting portion 66b of the curved portion flat pipe 66 has a width in the direction orthogonal to the cross-sectional longitudinal direction L1 of the curved portion flat pipe 66 from the inner edge 54c1 side of the curved portion 54c of the liquid header 54 to the liquid header 54. It does not have to be a shape that uniformly widens toward the outer edge 54c2 side of the curved portion 54c. For example, in the direction from the inner edge 54c1 side of the curved portion 54c of the liquid header 54 toward the outer edge 54c2 side of the curved portion 54c of the liquid header 54, the curved portion flat tube 66 having the cross-sectional shape of the connecting portion 66b of the curved portion flat tube 66. The rate of change in the width in the direction orthogonal to the longitudinal direction L1 of the cross section does not have to be constant.

Further, it is preferable that the cross-sectional shape of the connecting portion 66b of the curved portion flat tube 66 gradually widens from the inner edge 54c1 side of the curved portion 54c of the liquid header 54 toward the outer edge 54c2 side of the curved portion 54c of the liquid header 54. However, the cross-sectional shape of the connecting portion 66b of the curved portion flat tube 66 is a portion having a uniform width in a direction orthogonal to the longitudinal direction L1 of the cross section (the liquid header from the inner edge 54c1 side of the curved portion 54c of the liquid header 54). There may be a portion of the curved portion 54c of the 54 that does not widen toward the outer edge 54c2 side).

Further, the curvatures of the curved portions C1 and C2 at the ends of the main body portion 66a of the curved portion flat tube 66 in the longitudinal direction L1 of the cross section are the inner edge 54c1 side of the curved portion 54c of the liquid header 54 and the curved portion 54c of the liquid header 54. It is the same as the outer edge 54c2 side of (see FIG. 8). On the other hand, as shown in FIGS. 8 and 10, the curvature of the curved portion C1'on the inner edge 54c1 side of the curved portion 54c of the liquid header 54 of the connecting portion 66b of the curved portion flat tube 66 is the curvature of the liquid header 54. It is larger than the curvature of the curved portion C2'on the outer edge 54c2 side of the portion 54c.

Further, in the cross section of the main body portion 66a of the curved portion flat pipe 66, the shape (including the size) of the hole 61 forming the refrigerant flow path P is the same. On the other hand, when looking at the cross section of the connecting portion 66b of the curved portion flat tube 66, among the plurality of holes 61 arranged along the longitudinal direction L1 of the cross section, the inner edge 54c1 of the curved portion 54c of the liquid header 54 The shape of the closest hole 61a is different from the shape of the hole 61b closest to the outer edge 54c2 of the curved portion 54c of the liquid header 54 (see FIG. 10). Specifically, the size of the outer edge of the hole 61b on the outer edge 54c2 side is larger than the size of the outer edge of the hole 61a on the inner edge 54c1 side.

The outer shape of the connecting portion 66b of the curved portion flat tube 66 substantially coincides with the outer shape of the opening 55c provided in the curved portion 54c of the liquid header 54. More specifically, the shape of the connecting portion 66b of the curved portion flat tube 66 is substantially similar to the shape of the opening 55c provided in the curved portion 54c of the liquid header 54. The size of the connecting portion 66b of the curved portion flat tube 66 is slightly smaller than the size of the opening 55c provided in the curved portion 54c of the liquid header 54.

(3) Manufacturing Method of Heat Exchanger A manufacturing method of the heat source heat exchanger 50 will be described.

In the first step of manufacturing the heat source heat exchanger 50, the material to be the gas header 52 (a straight tube having an opening for inserting the heat transfer flat tube 60) and the material to be the liquid header 54 (transfer). A linear tube in which an opening 55 for inserting the heat flat tube 60 is formed) and is bent at the curved portions 52c and 54c by bending. As a result, the gas header 52 and the liquid header 54 having the shapes described in the above embodiments are manufactured.

It is preferable that the openings provided in the material serving as the gas header 52 and the material serving as the liquid header 54 have a uniform width in the direction orthogonal to the longitudinal direction of the openings. By providing the opening having such a shape in the material, the shape of the connecting portions 62b and 64b of the heat transfer flat tube 60 inserted into the straight portions 52a, 52b, 54a and 54b can be simplified as described above.

When such openings are provided in the headers 52 and 54, when the bending portions 52c and 54c are bent by bending, the openings provided in the curved portions 52c and 54c are deformed and as described above. The width of the curved portions 52c and 54c on the inner edge side is narrow, and the width of the curved portions 52c and 54c on the outer edge side is a wide opening. In other words, the shape of the openings provided in the curved portions 52c and 54c is a wedge shape in which the width of the curved portions 52c and 54c on the outer edge side is wider than the width of the curved portions 52c and 54c on the inner edge side.

In the second step of manufacturing the heat source heat exchanger 50, the first flat tube 62, the second flat tube 64, and the curved flat tube 66 are manufactured. Here, for convenience, the production of the first flat tube 62, the second flat tube 64, and the curved flat tube 66 is referred to as the second step of manufacturing the heat source heat exchanger 50, but the first flat tube 62, Since the production of the second flat tube 64 and the curved flat tube 66 is a separate step from the production of the gas header 52 and the liquid header 54, the first step and the second step may be performed at the same time.

In manufacturing the first flat tube 62, the second flat tube 64, and the curved flat tube 66, a heat transfer flat tube without connecting portions 62b, 64b, 64c (with a uniform outer peripheral size) is prepared. Will be done.

By performing dieless drawing on such a heat transfer flat tube (material), a first flat tube 62, a second flat tube 64, and a curved flat tube 66 having connection portions 62b, 64b, 64c are formed. To.

In the dieless drawing process, the material (here, the heat transfer flat tube before processing) is locally heated by a heating section using a high-frequency induction heating device, a laser heating device, etc., and the heating section (heating by the heating section) is used. The location) is moved relative to the material in the longitudinal direction of the material (the longitudinal direction of the heat transfer flat tube), and at the same time, a force along the longitudinal direction of the material is applied to the portion heated by the heating part of the material. This is a processing method in which the material is bulged in a direction intersecting the longitudinal direction or the material is stretched in the longitudinal direction.

Regarding the first flat tube 62 and the second flat tube 64, since the connecting portions 62b and 64b have a cross section similar to that of the main body portions 62a and 64a (parts that are not dieless drawn), the portions that become the connecting portions 62b and 64b are provided. While heating uniformly, a force is applied in the longitudinal direction of the material (in the direction of compressing the material).

On the other hand, since the cross section of the curved flat tube 66 is not similar to that of the main body 66a (the part where the dieless drawing process is not performed), the connection part 66b is heated while changing the degree of heating of the part to be the connection part 66b. A force is applied in the longitudinal direction of the material. In order to change the degree of heating of the portion to be the connecting portion 66b depending on the position, it is preferable to use a laser heating device or the like that can easily change the degree of heating locally for the heating portion. Due to such dieless drawing, the width of the connecting portion 66b of the curved flat tube 66 in the direction orthogonal to the longitudinal direction L1 is narrow on one end side and wide on the other end side in the longitudinal direction L1. The curved flat tube 66 can be manufactured.

Next, in the third step of manufacturing the heat source heat exchanger 50, the first flat tube 62, the curved flat tube 66, and the second flat tube 64 are in a state when they are attached to the headers 52 and 54. It is laminated. Specifically, the first flat tube 62 and the curved portion flat tube so that the first flat tube 62, the curved portion flat tube 66, and the second flat tube 64 are in the state when they are attached to the headers 52 and 54. 66 and the connection portions 62b, 66b, 64b of the second flat tube 64 are laminated.

Next, in the fourth step of manufacturing the heat source heat exchanger 50, at the end of a group of laminated heat transfer flat tubes 60 (first flat tube 62, curved flat tube 66, and second flat tube 64). The connection portions 62b, 66b, 64b are inserted into the openings of the gas header 52 and the liquid header 54 and fixed by brazing.

(4) Features Here, the features of the heat source heat exchanger 50 are described by taking the connection between the heat transfer flat tube 60 and the liquid header 54 as an example, but the connection between the heat transfer flat tube 60 and the gas header 52 is also a heat source. The heat exchanger 50 has similar characteristics. Here, in order to avoid duplication of description, the description of the characteristics of the heat source heat exchanger 50 regarding the connection between the heat transfer flat tube 60 and the gas header 52 is omitted.

(4-1)
The heat source heat exchanger 50 of the present embodiment includes a liquid header 54 and a plurality of heat transfer flat tubes 60. The liquid header 54 includes at least a first straight line portion 54a, a second straight line portion 54b, and a curved portion 54c. The first straight line portion 54a extends in the left-right direction. The second straight line portion 54b extends in a direction intersecting the left-right direction. The curved portion 54c connects between the first straight line portion 54a and the second straight line portion 54b. Each of the plurality of heat transfer flat tubes 60 is inserted into the opening 55 formed in the liquid header 54 and connected to the liquid header 54. The heat transfer flat tube 60 includes a curved flat tube 66 inserted and fixed in an opening 55c provided in the curved portion 54c. The longitudinal direction of the cross section of the curved flat tube 66 is the longitudinal direction of the cross section (front-back direction) of the heat transfer flat tube 60 (first flat tube 62) inserted and fixed in the opening 55a provided in the first straight line portion 54a. ) And the heat transfer flat tube 60 (second flat tube 64) inserted and fixed in the opening 55b provided in the second straight line portion 54b, and inclined with respect to each of the cross-sectional longitudinal direction (left-right direction). There is.

In the heat source heat exchanger 50 of the present embodiment, since the heat transfer flat tube 60 is also arranged in the curved portion 54c, the headers 52 and 54 have a shape having the curved portions 52c and 54c, and are compact and have high performance. The heat source heat exchanger 50 can be realized.

(4-2)
In the heat source heat exchanger 50 of the present embodiment, the size of the outer periphery of the connection portions 62b, 64b, 66b of each heat transfer flat tube 60 is larger than the size of the outer periphery other than the connection portions 62b, 64b, 66b. .. Specifically, the size of the outer periphery of the connecting portions 62b, 64b, 66b of each heat transfer flat tube 60 is larger than the size of the outer periphery of the main body portions 62a, 64a, 66a. The connecting portions 62b, 64b, and 66b are portions of each heat transfer flat tube 60 that are inserted and fixed in the opening 55 of the liquid header 54.

In the heat source heat exchanger 50 of the present embodiment, the liquid header 54 and the heat transfer flat tube 60 are brazed by forming a large outer periphery of the connection portions 62b, 64b, 66b of the heat transfer flat tube 60 with the liquid header 54. A relatively large attachment allowance can be secured, and it is easy to secure the strength of the connection portion between the liquid header 54 and the heat transfer flat tube 60.

Further, the heat transfer flat tube 60 can be appropriately used by forming a large outer circumference of the connection portions 62b, 64b, 66b with the liquid header 54 of the heat transfer flat tube 60 and using the connection portions 62b, 64b, 66b as spacers. It is easy to arrange them at intervals.

(4-3)
In the heat source heat exchanger 50 of the present embodiment, the heat transfer flat tube 60 (first flat tube 62) inserted and fixed in the openings 55a and 55b provided in the first straight line portion 54a and the second straight line portion 54b. And the width of the connecting portions 62b and 64b of the second flat tube 64) in the direction orthogonal to the longitudinal direction L1 of the cross section is uniform.

In the heat source heat exchanger 50 of the present embodiment, since the shapes of the connecting portions 62b and 64b of the heat transfer flat tube 60 connected to the first straight line portion 54a and the second straight line portion 54b of the liquid header 54 are simple, the liquid is liquid. It is relatively easy to manufacture the heat transfer flat tube 60 connected to the first straight line portion 54a and the second straight line portion 54b of the header 54.

(4-4)
In the heat source heat exchanger 50 of the present embodiment, the connecting portion 66b of the curved portion flat tube 66 is arranged on the outer edge 54c2 side of the first end portion E1 arranged on the inner edge 54c1 side of the curved portion 54c and the outer edge 54c2 of the curved portion 54c. It extends between the second end portion E2 and the curved portion flat tube 66 along the longitudinal direction L1 of the cross section. The width W3 of the connecting portion 66b of the curved portion flat pipe 66 in the direction orthogonal to the cross-sectional longitudinal direction L1 of the curved portion flat pipe 66 at the second end portion E2 is the cross-sectional length of the curved portion flat pipe 66 at the first end portion E1. It is wider than the width W2 in the direction orthogonal to the direction L1.

In the heat source heat exchanger 50 of the present embodiment, the width of the connecting portion 66b of the curved portion flat tube 66 connected to the curved portion 54c of the liquid header 54 is wide at the second end portion E2 on the outer edge 54c2 side of the curved portion 54c. , The first end E1 on the inner edge 54c1 side of the curved portion 54c is thin. Therefore, the outer shape of the connecting portion 66b of the curved portion flat tube 66 can correspond to the shape of the opening 55c of the curved portion 54c of the liquid header 54 previously bent in the curved portion 54c. Therefore, the heat source heat exchanger 50 in which the heat transfer flat tube 60 is also arranged in the curved portion 54c can be easily manufactured.

(4-5)
In the heat source heat exchanger 50 of the present embodiment, the cross-sectional shape of the connecting portion 66b of the curved portion flat tube 66 has a width in a direction orthogonal to the cross-sectional longitudinal direction L1 of the curved portion flat tube 66 from the first end portion E1 to the first. It is a wedge shape that gradually widens toward the two ends E2.

In the heat source heat exchanger 50 of the present embodiment, the cross-sectional shape of the connecting portion 66b of the curved portion flat tube 66 connected to the curved portion 54c of the liquid header 54 is from the first end portion E1 to the second end portion E2. It has a wide wedge shape. Therefore, it is easy to make the outer shape of the connecting portion 66b of the curved portion flat tube 66 correspond to the shape of the opening 55c of the curved portion 54c of the liquid header 54 previously bent in the curved portion 54c. Therefore, the heat source heat exchanger 50 in which the heat transfer flat tube 60 is also arranged in the curved portion 54c can be easily manufactured.

Here, the fact that the cross-sectional shape of the connecting portion 66b of the curved portion flat pipe 66 gradually widens from the first end portion E1 to the second end portion E2 is a direction orthogonal to the cross-sectional longitudinal direction L1 of the curved portion flat pipe 66. It does not mean only when the width increases proportionally from the first end E1 to the second end E2. The rate of change in the width in the direction orthogonal to the longitudinal direction L1 of the curved portion flat tube 66 in the direction along the longitudinal direction L1 of the curved portion flat tube 66 may differ depending on the location.

It is preferable that the cross-sectional shape of the connecting portion 66b of the curved flat tube 66 gradually widens from the first end E1 to the second end E2, but the cross-sectional shape of the connecting portion 66b of the curved flat tube 66. May have a shape having a uniform width in a direction orthogonal to the longitudinal direction L1 of the cross section.

(4-6)
In the heat source heat exchanger 50 of the present embodiment, the cross-sectional shape of the connecting portion 66b of the curved portion flat tube 66 is located on the curved portion C1'located on the inner edge 54c1 side of the curved portion 54c and on the outer edge 54c2 side of the curved portion 54c. The curved portion C2'and the curved portion C2'is included. The curvature of the curved portion C1'on the inner edge 54c1 side of the curved portion 54c is larger than the curvature of the curved portion C2'on the outer edge 54c2 side of the curved portion 54c.

By making the cross-sectional shape of the connecting portion 66b of the curved portion flat tube 66 such a shape, the connecting portion 66b of the curved portion flat tube 66 is previously bent in the curved portion 54c of the curved portion 54c of the liquid header 54. It is easy to correspond to the shape of the opening 55c. Therefore, the heat source heat exchanger 50 in which the heat transfer flat tube 60 is also arranged in the curved portion 54c can be easily manufactured.

(4-7)
In the heat source heat exchanger 50 of the present embodiment, when the cross section of the connecting portion 66b of the curved flat tube 66 is viewed, the connecting portion 66b of the curved flat tube 66 is arranged along the longitudinal direction L1 of the cross section. A plurality of holes 61 are formed. The shape of the hole 61a closest to the inner edge 54c1 of the curved portion 54c is different from the shape of the hole 61b closest to the outer edge 54c2 of the curved portion 54c. In the present embodiment, the length of the edge portion of the hole 61b is larger than the length of the edge portion of the hole 61a.

<Modification example>
A modified example of the above embodiment will be described below. It should be noted that each modification may be combined with the configuration of another modification as long as there is no contradiction.

(1) Modification A
The heat transfer tubes included in the heat exchangers of the present disclosure do not have to have the same shape or structure.

For example, the first flat tube 62, the second flat tube 64, and the curved flat tube 66 have specifications of the heat transfer flat tube (for example, the shape and number of holes 61, the outer periphery of the main body and the connection portion of the heat transfer flat tube, respectively. The size, etc.) may be different. Further, for example, even in the first flat tube 62, the specifications of the heat transfer flat tube may be different from each other. The same applies to the second flat tube 64 and the curved flat tube 66.

Further, for example, the arrangement pitch of the heat transfer flat tubes in the heat exchanger may not be uniform, and the arrangement pitch of the heat transfer tubes may differ depending on the location.

For example, the specifications of each heat transfer flat tube and the arrangement pitch of the heat transfer flat tubes are appropriately designed according to the wind speed distribution.

(2) Modification B
In the above embodiment, the extending direction of the refrigerant flow path P, in other words, the longitudinal direction of the heat transfer flat tube 60 is the vertical direction, but the present invention is not limited to this. For example, the extending direction of the refrigerant flow path P may be inclined with respect to the vertical direction and the horizontal direction. Further, the extending direction of the refrigerant flow path P may be the horizontal direction.

(3) Modification C
In the above embodiment, the gas header 52 is arranged above and the liquid header 54 is arranged below. In general, it is preferable that the gas header 52 is arranged above and the liquid header 54 is arranged below. However, the present invention is not limited to this, and the gas header 52 may be arranged below the liquid header 54.

<Additional Notes>
Although the embodiments of the present disclosure have been described above, it will be understood that various modifications of the embodiments and details are possible without departing from the spirit and scope of the present disclosure described in the claims. ..

The present disclosure is widely applicable to heat exchangers that do not use heat transfer fins.

50 Heat source heat exchanger (heat exchanger)
52 Gas header (header)
52a 1st straight line part 52b 2nd straight line part 52c Curved part 54 Liquid header (header)
54a First straight section 54b Second straight section 54c Curved section 55a Opening (opening provided in the first straight section)
55b opening (opening provided in the second straight section)
55c opening (opening provided in the curved part)
61 hole 61a hole (hole closest to the inner edge of the curved part)
61b hole (the hole closest to the outer edge of the curved part)
62 First flat tube (heat transfer flat tube)
64 Second flat tube (heat transfer flat tube)
66 Curved flat tube (heat transfer flat tube)
C1'Curved part (curved part on the inner edge side of the curved part)
C2'Curved part (curved part on the outer edge side of the curved part)
E1 1st end E2 2nd end

International Publication No. 2005/073655

Claims (4)

The first straight line portion (52a, 54a) extending in the first direction, the second straight line portion (52b, 54b) extending in the second direction intersecting the first direction, and the first straight line portion and the second straight line portion. A header (52,54) including at least a curved portion (52c, 54c) connecting between and
A plurality of heat transfer flat tubes (62, 64, 66) inserted into the openings (55a, 55b, 55c) formed in the header and connected to the header.
Equipped with
The longitudinal direction of the curved portion flat tube (66) inserted and fixed in the opening (55c) provided in the curved portion of the heat transfer flat tube is provided in the first straight line portion. It is inserted and fixed in the opening (55b) provided in the longitudinal direction of the cross section of the heat transfer flat tube (62) and the second straight line portion which is inserted and fixed in the opening (55a). The heat transfer flat tube (64) is inclined with respect to each of the longitudinal directions of the cross section.
The size of the outer circumference of each connection portion (62b, 64b, 66b) inserted and fixed in the opening of the header of each of the heat transfer flat tubes is larger than the size of the outer circumference other than the connection portion. ,
The width (W1) in the direction orthogonal to the longitudinal direction of the cross section of the connection portion of the heat transfer flat tube inserted and fixed in the opening provided in the first straight line portion and the second straight line portion is Uniform and
The connection portion of the curved portion flat tube has a first end portion (E1) arranged on the inner edge (54c1) side of the curved portion and a second end portion (54c2) arranged on the outer edge (54c2) side of the curved portion. The width (W3) of the second end portion extending between E2) and the curved portion flat tube along the longitudinal direction of the cross section of the curved portion flat tube is the width (W3) in the direction orthogonal to the longitudinal direction of the cross section of the curved portion flat tube. It is wider than the width (W2) in the direction orthogonal to the longitudinal direction of the cross section of the curved portion flat tube in the portion.
Heat exchanger (50). The cross-sectional shape of the connection portion of the curved portion flat tube is a wedge shape in which the width in the direction orthogonal to the cross-sectional longitudinal direction of the curved portion flat tube gradually widens from the first end portion toward the second end portion. Is,
The heat exchanger according to claim 1 . The cross-sectional shape of the connection portion of the curved portion flat tube includes curved portions (C1', C2') on the inner edge side of the curved portion and the outer edge side of the curved portion.
The curvature of the curved portion (C1') on the inner edge side of the curved portion is larger than the curvature of the curved portion (C2') on the outer edge side of the curved portion.
The heat exchanger according to claim 1 or 2 . When the cross section of the connection portion of the curved portion flat tube is viewed, a plurality of holes (61) arranged along the longitudinal direction of the cross section are formed in the connection portion of the curved portion flat tube.
The shape of the hole (61a) closest to the inner edge of the curved portion is different from the shape of the hole (61b) closest to the outer edge of the curved portion.
The heat exchanger according to any one of claims 1 to 3 .

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