Heat exchanger and air conditioner

Abstract

To provide a heat exchanger capable of distributing a homogeneous refrigerant to a plurality of heat transfer pipes even under gravity, and to provide an air conditioner.SOLUTION: A heat exchanger 37 includes a plurality of heat transfer pipes 43, and a first header 39. The first header 39 includes a laminate 59 on which a first plate 53 having a through-hole 51 for allowing a refrigerant to flow in, a second plate 55 to which the plurality of heat transfer pipes 43 is connected, and a plurality of intermediate plates 57 arranged between the first plate 53 and the second plate 55 are laminated. The laminate 59 includes: a front chamber 75 connected to the through-hole 51 of the first plate 53; a plurality of rear chambers 77, 79 arranged side by side having an interval in the first direction from the front chamber 75, and connected to each of the heat transfer pipes 43; and a plurality of flow passages 69, 73 for allowing the refrigerant to flow into the rear chambers 77, 79 respectively from the front chamber 75. Each of the plurality of flow passages 69, 73 has inlets 69a, 73a provided at a partition wall 81 for partitioning the front chamber 75 and the rear chamber 79 adjacent to the front chamber 75.SELECTED DRAWING: Figure 3

Description

Technical Field

[0001] Embodiments of the present invention relate to a heat exchanger and an air conditioner.

Background Art

[0002] There is known a heat exchanger having a stacked header which is a distributor for distributing and supplying refrigerant to a plurality of heat transfer tubes of the heat exchanger.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] The stacked header of the heat exchanger has two flow paths branching up and down as a minimum configuration for distributing and supplying refrigerant to a plurality of heat transfer tubes arranged in parallel vertically, for example, two heat transfer tubes. One flow path extends upward to supply refrigerant to the upper heat transfer tube, and the other flow path extends downward to supply refrigerant to the lower heat transfer tube. In this case, when distributing the gas-liquid two-phase refrigerant to the two branched flow paths of the stacked header, under the influence of gravity, in the flow path for supplying refrigerant to the upper heat transfer tube, the proportion of the gas refrigerant having a lower density than the liquid refrigerant varies, and in the flow path for supplying refrigerant to the lower heat transfer tube, the proportion of the liquid refrigerant varies. That is, in the conventional stacked header, it is difficult to homogenize the distribution of the gas-liquid two-phase refrigerant. If the ratio of the gas refrigerant and the liquid refrigerant is different between the upper heat transfer tube and the lower heat transfer tube, the performance of the heat exchanger deteriorates.

[0005] Therefore, an object of the present invention is to provide a heat exchanger and an air conditioner capable of distributing a uniform refrigerant to a plurality of heat transfer tubes even under gravity.

Means for Solving the Problems

[0006] To solve the above problems, a heat exchanger according to an embodiment of the present invention includes a plurality of heat transfer tubes that are arranged at intervals in a first direction and have refrigerant flow paths through which refrigerant flows, and a first header connected to at least one end of the plurality of heat transfer tubes in the extending direction thereof. The first header has a laminated body formed by laminating a first plate having a through hole for allowing the refrigerant to flow in, a second plate to which the plurality of heat transfer tubes are connected, and a plurality of intermediate plates disposed between the first plate and the second plate. The laminated body has a front chamber connected to the through hole of the first plate, a plurality of rear chambers arranged at intervals in the first direction from the front chamber and each connected to a corresponding one of the heat transfer tubes, and a plurality of flow paths for allowing the refrigerant to flow from the front chamber into each of the rear chambers. Each of the plurality of flow paths has an inlet provided in a partition wall separating the front chamber and the rear chamber adjacent to the front chamber.

[0007] In addition, an air conditioner according to an embodiment of the present invention for solving the above problems includes the heat exchanger in which the front chamber is disposed above the plurality of rear chambers.

Brief Description of the Drawings

[0008]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Mode for Carrying Out the Invention

[0009] The heat exchanger and air conditioning according to the present embodiment will be described with reference to FIGS. 1 to 6. In the plurality of drawings, the same or corresponding components are denoted by the same reference numerals.

[0010] FIG. 1 is a schematic diagram of the refrigeration cycle of the air conditioner 1 according to an embodiment of the present invention.

[0011] As shown in FIG. 1, the air conditioner 1 according to the present embodiment includes an indoor unit 3 and an outdoor unit 5.

[0012] The indoor unit 3 includes an indoor unit housing 11, an indoor heat exchanger 13 housed in the indoor unit housing 11, and an indoor blower 15 that generates an air flow passing through the indoor heat exchanger 13.

[0013] The outdoor unit 5 includes an outdoor unit housing 21, a compressor 23 housed in the outdoor unit housing 21, a four-way valve 25 housed in the outdoor unit housing 21, an outdoor heat exchanger 27 housed in the outdoor unit housing 21, an expansion device 29, and an outdoor blower 31 housed in the outdoor unit housing 21 that generates an air flow passing through the outdoor heat exchanger 27. The expansion device 29 is, for example, an electronic expansion valve (Pulse Motor Valve, PMV).

[0014] The air conditioner 1 includes a refrigerant pipe 33 that sequentially connects the compressor 23, the four-way valve 25, the outdoor heat exchanger 27, the expansion device 29, and the indoor heat exchanger 13 to circulate the refrigerant. The air conditioner 1 switches between a cooling operation in which the refrigerant flows as shown by the broken line in FIG. 1 and a heating operation in which the refrigerant flows as shown by the solid line.

[0015] During the cooling operation, the air conditioner 1 discharges the high-temperature and high-pressure gaseous refrigerant compressed from the compressor 23, and sends this refrigerant to the outdoor heat exchanger 27 via the four-way valve 25. The outdoor heat exchanger 27 performs heat exchange between the outdoor air and the refrigerant, condenses the refrigerant, and makes it into a high-pressure liquid phase state. That is, the outdoor heat exchanger 27 functions as a condenser. The refrigerant that has passed through the outdoor heat exchanger 27 passes through the expansion device 29 and is depressurized to become a low-pressure gas-liquid two-phase refrigerant and reaches the indoor heat exchanger 13. The indoor heat exchanger 13 performs heat exchange between the indoor air and the gas-liquid two-phase refrigerant, cools the air blown into the indoor space, and at the same time evaporates the refrigerant to cause a transition from the gas-liquid two-phase state to the gaseous state. That is, the indoor heat exchanger 13 functions as an evaporator. The refrigerant that has passed through the indoor heat exchanger 13 is sucked back into the compressor 23.

[0016] During the heating operation, the air conditioner 1 reverses the four-way valve 25 to generate a refrigerant flow in the refrigeration cycle that is opposite to the refrigerant flow during the cooling operation. That is, the indoor heat exchanger 13 functions as a condenser, and the outdoor heat exchanger 27 functions as an evaporator. Specifically, the air conditioner 1 sends the high-temperature and high-pressure gaseous refrigerant compressed from the compressor 23 to the indoor heat exchanger 13 via the four-way valve 25. The indoor heat exchanger 13 performs heat exchange between the indoor air and the refrigerant, warms the air blown into the indoor space, and at the same time condenses the refrigerant to make it into a high-pressure liquid phase state. That is, the indoor heat exchanger 13 functions as a condenser. The refrigerant that has passed through the indoor heat exchanger 13 passes through the expansion device 29 and is depressurized to become a low-pressure gas-liquid two-phase refrigerant and reaches the outdoor heat exchanger 27. The outdoor heat exchanger 27 performs heat exchange between the outdoor air and the gas-liquid two-phase refrigerant, evaporates the refrigerant, and causes a transition from the gas-liquid two-phase state to the gaseous state. That is, the outdoor heat exchanger 27 functions as an evaporator. The refrigerant that has passed through the outdoor heat exchanger 27 is sucked back into the compressor 23.

[0017] In the case of the air conditioner 1 capable of heating and cooling, the flow direction of the refrigerant in the indoor heat exchanger 13 and the outdoor heat exchanger 27 is reversed (becomes opposite) between the cooling operation and the heating operation. Therefore, the indoor heat exchanger 13 and the outdoor heat exchanger 27 that function as evaporators are hereinafter simply referred to as the heat exchanger 37. Hereinafter, unless otherwise specified, the heat exchanger 37 that functions as an evaporator will be described.

[0018] FIG. 2 is a schematic view of the heat exchanger 37 according to an embodiment of the present invention.

[0019] As shown in FIG. 2, the heat exchanger 37 according to the present embodiment has a rectangular plate-like appearance.

[0020] The air heat-exchanged by the heat exchanger 37 flows in the front-back direction of the paper surface in FIG. 2. In other words, the air heat-exchanged by the heat exchanger 37 flows in a direction penetrating the front and back of the plate-like heat exchanger 37. The direction in which the air heat-exchanged by the heat exchanger 37 flows is referred to as the "air flow direction" of the heat exchanger 37.

[0021] The heat exchanger 37 includes two headers 39 and 41 spaced apart from each other and arranged in parallel, a plurality of heat transfer tubes 43 arranged in the extending direction X of the two headers 39 and 41 and installed between the two headers 39 and 41 to allow the refrigerant to flow between the first header 39 and the second header 41, and a plurality of plate-like fins 45 joined to the plurality of heat transfer tubes 43. Note that the heat exchanger 37 may not include the second header 41. In that case, for example, a serpentine tube, which is a serpentine-type heat transfer tube, can be used as the heat transfer tube 43. Also, in the present embodiment, the extending direction X of the first header 39 and the second header 41 may be referred to as the "first direction" or the "vertical direction".

[0022] The heat exchanger 37, for example, diverts the refrigerant flowing from a first joint (not shown) connected to the refrigerant pipe 33 into the first header 39 to a plurality of heat transfer tubes 43, combines the refrigerant that has passed through the heat transfer tubes 43 and undergone heat exchange in the second header 41, and causes the refrigerant to flow out from the second header 41 to a second joint (not shown) that is different from the first joint and is connected to the refrigerant pipe 33.

[0023] The first header 39, the second header 41, the heat transfer tubes 43, the plate fins 45, the first joint, and the second joint are usually made of aluminum or an aluminum alloy. The first header 39, the second header 41, the heat transfer tubes 43, and the plate fins 45 are usually integrated by brazing.

[0024] The first header 39 is connected to the refrigerant pipe 33 indirectly via the first joint or directly. Also, the second header 41 is connected to the refrigerant pipe 33 indirectly via the second joint or directly.

[0025] The plurality of heat transfer tubes 43 are arranged substantially equidistantly in the extending direction X of the first header 39 and the second header 41. The plurality of heat transfer tubes 43 extend substantially orthogonally to the first header 39 and the second header 41. Each end of the plurality of heat transfer tubes 43 in the extending direction of the plurality of heat transfer tubes 43 is inserted into and fixed to the first header 39 and the second header 41. Incidentally, when the plurality of heat transfer tubes 43 are serpentine tubes as described above and the heat exchanger 37 does not include the second header 41, each end of the plurality of heat transfer tubes 43 is inserted into and fixed to the first header 39.

[0026] The plurality of heat transfer tubes 43 are flat tubes having a flat rectangular cross-section with rounded corners. Specifically, the short side in the cross-sectional shape of the heat transfer tube 43 extends in the direction in which the plurality of heat transfer tubes 43 are arranged, that is, in the extending direction X of the first header 39 and the second header 41. The long side in the cross-sectional shape of the heat transfer tube 43 extends in the direction penetrating the front and back of the heat exchanger 37, that is, in the air flow direction of the heat exchanger 37. A pair of adjacent heat transfer tubes 43 face each other with the wide surface corresponding to the long side in the cross-sectional shape.

[0027] Each heat transfer tube 43 has a plurality of refrigerant flow paths (not shown) arranged in the direction penetrating the front and back of the heat exchanger 37, that is, in the air flow direction of the heat exchanger 37. In the plurality of refrigerant flow paths, the refrigerant circulated between the first header 39 and the second header 41 flows through the heat transfer tube 43. The plurality of refrigerant flow paths extend substantially parallel to the extending direction of the heat transfer tube 43. Each of the plurality of refrigerant flow paths is connected to the first header 39 at one end and to the second header 41 at the other end. The heat transfer tube 43 is generally manufactured by extrusion molding of aluminum.

[0028] The plurality of plate-like fins 45 are a plurality of thin plates having the same rectangular shape. The plurality of plate-like fins 45 are arranged substantially at equal intervals in the extending direction of the plurality of heat transfer tubes 43. Each of the plate-like fins 45 is brazed to the plurality of heat transfer tubes 43 so as to be heat-transferable, and expands the heat transfer area of the heat transfer tubes 43.

[0029] Next, the first header 39 of the heat exchanger 37 will be described in detail.

[0030] FIG. 3(A) is a perspective view of the first header 39 of the first example in the heat exchanger 37 according to the embodiment of the present invention, FIG. 3(B) is an exploded perspective view of the first header 39 of the first example in the heat exchanger 37 according to the embodiment of the present invention, and FIG. 3(C) is a cross-sectional view of the first header 39 of the first example in the heat exchanger 37 according to the embodiment of the present invention.

[0031] In the examples of FIGS. 3(A) to 3(C), the first header 39 assumes the diversion of the refrigerant to two heat transfer tubes 43 for convenience of explanation. However, this is the minimum configuration, and the number of the plurality of heat transfer tubes 43 for diverting the refrigerant is not particularly limited. The same applies to the other figures described hereinafter. Also, the cross-sectional view of FIG. 3(C) is a cross-sectional view cut parallel to the stacking direction of the laminate 59 described later with reference to the A-A line of the first header 39 of FIG. 3(A). The other cross-sectional views described hereinafter are also obtained at the same position as the A-A line.

[0032] As shown in FIGS. 3(A) to 3(C), at least the first header 39 of the heat exchanger 37 has a first plate 53 having a through hole 51 for allowing a refrigerant to flow in, a second plate 55 to which a plurality of heat transfer tubes 43 are connected, and a plurality of intermediate plates 57 disposed between the first plate 53 and the second plate 55, and has a laminate 59 formed by laminating them. The first header 39 is also called a laminated header. Hereinafter, the first plate 53 side may be referred to as one side of the laminate 59 and the second plate 55 side may be referred to as the other side of the laminate 59.

[0033] Note that the second header 41 may be a laminated header similar to the first header 39, or may be a header pipe as a straight pipe having a circular cross section (annular cross section). Further, it may be a header or the like having any other shape.

[0034] The laminate 59 has a flow splitting structure for splitting the refrigerant into a plurality of heat transfer tubes 43, which is provided by combining through holes and through regions provided in the first plate 53, the second plate 55, and the plurality of intermediate plates 57 described below.

[0035] The outer shapes of the first plate 53, the second plate 55, and the plurality of intermediate plates 57 are the same rectangular shape. Specifically, the short side direction of each of the first plate 53, the second plate 55, and the plurality of intermediate plates 57 coincides with the air flow direction of the heat exchanger 37, and the longitudinal direction of each of the first plate 53, the second plate 55, and the plurality of intermediate plates 57 coincides with the extending direction X of the two headers 39 and 41. Further, the thickness direction of each of the first plate 53, the second plate 55, and the plurality of intermediate plates 57 coincides with the lamination direction of the laminate 59. Also, the longitudinal direction and the short side direction of the first plate 53, the second plate 55, and the plurality of intermediate plates 57 are orthogonal to the extending direction of the heat transfer tubes 43. The first plate 53, the second plate 55, and the plurality of intermediate plates 57 are each processed by press working or cutting working.

[0036] The first plate 53, the second plate 55, and the plurality of intermediate plates 57 are each provided with a brazing material layer on at least one of the joint surfaces with the adjacent plates 53, 55, 57. Therefore, by stacking the first plate 53, the second plate 55, and the plurality of intermediate plates 57 and heating them in a heating furnace, the brazing material melts and the laminate 59 is brazed and joined.

[0037] The through-hole 51 penetrating in the thickness direction of the first plate 53 is arranged on a center line passing through the center in the short side direction of the first plate 53 and extending in the longitudinal direction, and in the vicinity of one side in the short side direction of the first plate 53.

[0038] The second plate 55 has a plurality of heat transfer tube insertion holes 61 (61a, 61b) penetrating in the thickness direction of the second plate 55. The shape of the heat transfer tube insertion hole 61 is an oval shape having the short side direction of the second plate 55 as the major axis direction and the longitudinal direction of the second plate 55 as the minor axis direction. The plurality of heat transfer tube insertion holes 61 (61a, 61b) are arranged side by side in the longitudinal direction of the second plate 55. The end portion in the extending direction of the heat transfer tube 43 is inserted into the heat transfer tube insertion hole 61.

[0039] The plurality of intermediate plates 57 include, for example, a first intermediate plate 57a, a second intermediate plate 57b, and a third intermediate plate 57c.

[0040] The first intermediate plate 57a, the second intermediate plate 57b, and the third intermediate plate 57c each have a first through region 63 and a second through region 65 penetrating in their respective thickness directions.

[0041] The shapes of the first through region 63 and the second through region 65 are, for example, rectangular shapes having the sides extending in the short side direction of their respective intermediate plates 57 as the long sides. The first through region 63 and the second through region 65 are arranged in parallel with a space therebetween on a center line passing through the center in the short side direction of their respective intermediate plates 57 and extending in the longitudinal direction.

[0042] The first intermediate plate 57a has, in addition to the first through region 63 and the second through region 65 described above, a third through region 67 that penetrates in the thickness direction of the first intermediate plate 57a and connects the first through region 63 and the second through region 65. The shape of the third through region 67 is, for example, a rectangular shape with a long side along the longitudinal direction of the first intermediate plate 57a. The third through region 67 is substantially orthogonal to the first through region 63 and the second through region 65. The third through region 67 is a first flow path 69 that is closed by the first plate 53 and the second intermediate plate 57b.

[0043] The third intermediate plate 57c has, in addition to the first through region 63 and the second through region 65 described above, a fourth through region 71 that penetrates in the thickness direction of the third intermediate plate 57c, and a fifth through region 72 that penetrates in the thickness direction of the third intermediate plate 57c and connects the first through region 63 and the fourth through region 71.

[0044] The shape of the fourth through region 71 is, for example, a rectangular shape with a long side along the short side direction of the third intermediate plate 57c. The fourth through region 71 is arranged substantially parallel to and spaced apart from the first through region 63 and the second through region 65. The fourth through region 71 is arranged between the first through region 63 and the second through region 65. The fourth through region 71 is a second rear chamber 79, which will be described later, and is closed by the second intermediate plate 57b and the second plate 55.

[0045] The shape of the fifth through region 72 is, for example, a rectangular shape with a long side along the short side direction of the third intermediate plate 57c. The fifth through region 72 is substantially orthogonal to the first through region 63 and the fourth through region 71. The fifth through region 72 is a second flow path 73 that is closed by the second intermediate plate 57b and the second plate 55.

[0046] The laminate 59 formed by the first plate 53, the second plate 55, and the plurality of intermediate plates 57 described above has a front chamber 75, a first rear chamber 77, and a second rear chamber 79.

[0047] Each first through-region 63 of the plurality of intermediate plates 57 is a continuous front chamber 75 that is connected in one piece and closed in the stacking direction of the laminate 59 by the first plate 53 and the second plate 55. The internal space of the front chamber 75 is connected to the through-hole 51 of the first plate 53. In other words, the laminate 59 has a front chamber 75 connected to the through-hole 51 of the first plate 53.

[0048] Each second through-region 65 of the plurality of intermediate plates 57 is a continuous first rear chamber 77 that is connected in one piece and closed in the stacking direction of the laminate 59 by the first plate 53 and the second plate 55. The internal space of the first rear chamber 77 is connected to the heat transfer tube insertion hole 61a of the second plate 55.

[0049] The fourth through-region 71 of the third intermediate plate 57c is a second rear chamber 79 that is closed in the stacking direction of the laminate 59 by the second intermediate plate 57b and the second plate 55. The internal space of the second rear chamber 79 is connected to the heat transfer tube insertion hole 61b of the second plate 55.

[0050] The positional relationship between the first rear chamber 77 and the second rear chamber 79 with respect to the above-described front chamber 75 is arranged at intervals from each other in the longitudinal direction (first direction) of the intermediate plate 57. Specifically, the first rear chamber 77 is located below the front chamber 75. Also, the second rear chamber 79 is located below the front chamber 75 and above the first rear chamber 77. That is, it can be said that the laminate 59 has a plurality of rear chambers 77, 79 arranged below the front chamber 75 and each connected to the respective heat transfer tube 43.

[0051] The first flow path 69 and the second flow path 73 provided in the laminate 59 are each connected substantially orthogonally to the front chamber 75. Therefore, the inlet 69a of the first flow path 69 and the inlet 73a of the second flow path 73 are respectively provided on the partition wall 81 that separates the front chamber 75 and the second rear chamber 79 adjacent to the front chamber 75. Specifically, the partition wall 81 of the front chamber 75 in the laminate 59 has a substantially rectangular surface as shown in FIG. 3(C). When the first direction (vertical direction) of the first header 39 coincides with the gravitational direction, the partition wall 81 of the front chamber 75 coincides with the lower surface (bottom surface) of the front chamber 75. The inlet 69a of the first flow path 69 provided on one side of the laminate 59 and the inlet 73a of the second flow path 73 provided on the other side of the laminate 59 are provided such that a part of the partition wall 81 of the front chamber 75 communicates with the first flow path 69 and the second flow path 73 and is on the diagonal line.

[0052] The first flow path 69 of the laminate 59 allows the refrigerant to flow from the front chamber 75 into the first rear chamber 77. Also, the second flow path 73 of the laminate 59 allows the refrigerant to flow from the front chamber 75 into the second rear chamber 79. That is, it can be said that the laminate 59 has a plurality of flow paths 69, 73 that allow the refrigerant to flow from the front chamber 75 into the respective rear chambers 77, 79.

[0053] Next, referring to FIG. 3(B), an example of the flow of the refrigerant flowing into the first header 39 having the refrigerant distribution structure as described above will be described. Here, the flow of the refrigerant is assumed to be during the operation of the air conditioner 1 equipped with the heat exchanger 37 in which the front chamber 75 is disposed above the plurality of rear chambers 77, 79. The same shall apply to other figures for explaining the flow of the refrigerant described hereinafter. Also, the flow of the refrigerant flowing through the first header 39 is denoted by arrows F1 to F7 and arrows F5' to F12'.

[0054] First, the gas-liquid two-phase refrigerant flows through the through holes 51 of the first plate 53 and into the front chamber 75 of the first header 39 (arrows F1 to F4). The flowing-in refrigerant collides with the second plate 55 which is the wall of the front chamber 75 and branches in the horizontal direction and in two directions (arrows F5 and F5').

[0055] One of the refrigerants branched by the second plate 55 reaches the inlet 73a of the second flow path 73 located on the other side of the laminate 59. The refrigerant that has reached the inlet 73a of the second flow path 73 flows downward through the second flow path 73 and is stored in the second rear chamber 79 (arrow F6). The refrigerant stored in the second rear chamber 79 flows into the upper heat transfer tube 43 out of the two heat transfer tubes 43 through the heat transfer tube insertion hole 61b from the second rear chamber 79 (arrow F7).

[0056] The other refrigerant branched by the second plate 55 is rebounded by the collision with the second plate 55 and reaches the inlet 69a of the first flow path 69 located on one side of the laminate 59. The refrigerant that has reached the inlet 69a of the first flow path 69 flows downward through the first flow path 69 and is stored in the first rear chamber 77 (arrows F6' to F11'). The refrigerant stored in the first rear chamber 77 flows into the lower heat transfer tube 43 out of the two heat transfer tubes 43 through the heat transfer tube insertion hole 61a from the first rear chamber 77 (arrow F12').

[0057] Here, the homogeneity of the gas-liquid two-phase refrigerant branched from the front chamber 75 and flowing into the plurality of flow paths 69 and 73 in the first header 39 will be described.

[0058] The gas-liquid two-phase refrigerant flowing into the front chamber 75 from the through hole 51 is diverted from the front chamber 75 to a plurality of rear chambers 77, 79 existing below the front chamber 75 through a plurality of flow paths 69, 73. In other words, the first header 39 has a plurality of flow paths 69, 73 that branch downward from the front chamber 75, rather than flow paths that branch vertically from the front chamber 75. Therefore, when the first direction (vertical direction) of the first header 39 and the gravitational direction are arranged to coincide, the gas-liquid two-phase refrigerant flowing into the front chamber 75 can be evenly diverted to each of the plurality of flow paths 69, 73. Further, since the inlets 69a, 73a of each of the plurality of flow paths 69, 73 are provided in the partition wall 81 that forms the lower surface (floor surface) of the front chamber 75, the refrigerant accumulating at the bottom of the front chamber 75 flows downward through each of the flow paths 69, 73 from the same height. That is, the first header 39 distributes the gas-liquid two-phase refrigerant flowing into the front chamber 75 to the plurality of flow paths 69, 73 and supplies it to the two heat transfer tubes 43 existing below the front chamber 75. Also, if the opening cross-sectional areas of the inlets 69a, 73a of each of the plurality of flow paths 69, 73 are the same, the first header 39 can distribute and supply the gas-liquid two-phase refrigerant flowing into the front chamber 75 to the two heat transfer tubes 43 substantially equally.

[0059] Next, a modified example of the first header 39 provided in the heat exchanger 37 will be described.

[0060] FIG. 4 is a cross-sectional view of a first header 39A of a second example in the heat exchanger 37 according to an embodiment of the present invention.

[0061] As shown in FIG. 4, in the first header 39A, the opening cross-sectional area of the inlet 69a of the first flow path 69 and the opening cross-sectional area of the inlet 73a of the second flow path 73 may be different. That is, the opening cross-sectional areas of the inlets 69a and 73a of the plurality of flow paths 69 and 73 may be different from each other. In the example of FIG. 4, the opening cross-sectional area of the inlet 73a of the second flow path 73 is smaller than the opening cross-sectional area of the inlet 69a of the first flow path 69. Due to the characteristics of the refrigerant flow flowing from the through-hole 51 into the front chamber 75 of the first header 39A, that is, the flow momentum flowing from the first plate 53 provided with the through-hole 51 on one side of the laminate 59 into the front chamber 75 and heading toward the second plate 55 on the other side of the laminate 59, there may be a case where the refrigerant flows more easily into the second flow path 73 located on the other side of the laminate 59 than into the first flow path 69 located on one side of the laminate 59. In this case, by making the opening cross-sectional area of the inlet 73a of the second flow path 73 smaller than the opening cross-sectional area of the inlet 69a of the first flow path 69, the flow rates of the refrigerant flowing into the first flow path 69 and the second flow path 73 are adjusted to appropriate amounts respectively.

[0062] The opening cross-sectional area of the inlet 69a of the first flow path 69 can be adjusted, for example, by changing the width of the third through-region 67 provided in the first intermediate plate 57a. Specifically, when the third through-region 67 penetrates in the thickness direction of the first intermediate plate 57a, it can be adjusted by changing the length of the width in the short direction of the third through-region 67. Further, the opening cross-sectional area of the inlet 69a of the first flow path 69 can be adjusted by providing a first recess (not shown) connecting the first through-region 63 and the second through-region 65 in the first intermediate plate 57a instead of the third through-region 67, and changing the length of the first intermediate plate 57a in the short direction or the length in the thickness direction of the first intermediate plate 57a. The first recess does not have to penetrate the first intermediate plate 57a like the third through-region 67. When a first recess is provided in the first intermediate plate 57a instead of the third through-region 67, the first recess is the first flow path 69 blocked by the first plate 53 or the second intermediate plate 57b.

[0063] Similarly, the opening cross-sectional area of the inlet 73a of the second flow path 73 can be adjusted, for example, by changing the width of the fifth through region 72 provided in the third intermediate plate 57c. Specifically, when the fifth through region 72 penetrates in the thickness direction of the third intermediate plate 57c, it can be adjusted by changing the length of the width of the fifth through region 72 in the short direction. Further, instead of the fifth through region 72, the opening cross-sectional area of the inlet 73a of the second flow path 73 can be adjusted by providing a second recess 83 that connects the first through region 63 and the fourth through region 71 in the third intermediate plate 57c, and changing the length of the second recess 83 in the short direction of the third intermediate plate 57c or the length in the thickness direction of the third intermediate plate 57c. The second recess 83 does not have to penetrate the third intermediate plate 57c like the fifth through region 72. In the third intermediate plate 57c, when the second recess 83 is provided instead of the fifth through region 72, the second recess 83 is the second flow path 73 blocked by the second intermediate plate 57b or the second plate 55.

[0064] FIG. 5(A) is an exploded perspective view of a first header 39B of a third example in the heat exchanger 37 according to an embodiment of the present invention, and FIG. 5(B) is a cross-sectional view of the first header 39B of the third example in the heat exchanger 37 according to an embodiment of the present invention.

[0065] As shown in FIGS. 5(A) and 5(B), the front chamber 75 may have a guide wall 85 that changes the direction of the refrigerant flowing in from the through hole 51. In the examples of FIGS. 5(A) and 5(B), the guide wall 85 is provided substantially perpendicular to the partition wall 81 of the front chamber 75 in a substantially J shape from one side edge of the through hole 51 closer to the first flow path 69 to the other side edge of the through hole 51 in the front chamber 75.

[0066] The guide wall 85 can be configured by providing a non-through region in at least one first through region 63 of the plurality of intermediate plates 57.

[0067] Specifically, a first non-through region 87 is provided in a first through region 63 of the first intermediate plate 57a. For example, the first non-through region 87 has a rectangular shape with a long side being a side extending in the thickness direction of the first intermediate plate 57a. One end surface of the first non-through region 87 in the thickness direction of the first intermediate plate 57a is in contact with the surface of the first plate 53 in the vicinity of the through hole 51.

[0068] Furthermore, a second non-through region 89 is provided in the first through region 63 of the second intermediate plate 57b. The second non-through region 89 has a recess 89a that is recessed in the thickness direction of the second intermediate plate 57b from one surface of the second intermediate plate 57b facing the first intermediate plate 57a. The recess 89a faces the through hole 51. The second non-through region 89 has two end portions extending in the thickness direction of the second intermediate plate 57b.

[0069] One end surface of one of the two end portions of the second non-through region 89 and the other end surface of the first non-through region 87 are substantially aligned and in contact. Also, one end surface of the other of the two end portions of the second non-through region 89 faces the first through region 63 of the first intermediate plate 57a with a gap therebetween. The other of the two end portions of the second non-through region 89 is referred to as an end portion 85a of the induction wall 85. Therefore, after brazing the laminate 59, the first non-through region 87 and the second non-through region 89 are integrated to form the induction wall 85.

[0070] Here, referring back to FIG. 3(B), the flow of the refrigerant in the first header 39 will be further described. After the refrigerant flows into the front chamber 75 of the first header 39 through the through-hole 51, before colliding with the second plate 55 which is the wall of the front chamber 75, a part of it may flow into the first flow path 69 located on one side of the laminate 59. That is, the refrigerant can flow directly into the first flow path 69 following arrow F1 and then arrow F9′, without going through the flow from arrow F5′ to arrow F9′. Also, for example, when the outdoor unit 5 equipped with the heat exchanger 37 is installed not horizontally but tilted, and the inlet 69a of the first flow path 69 is lower than the inlet 73a of the second flow path 73, the refrigerant is likely to flow into the first flow path 69. Therefore, even in these cases, since the front chamber 75 has the guiding wall 85, the refrigerant will flow as described below, making it easier to evenly distribute the refrigerant to the first flow path 69 and the second flow path 73. That is, the guiding wall 85 appropriately adjusts the flow rates of the refrigerant flowing into the first flow path 69 and the second flow path 73 respectively.

[0071] Referring again to FIGS. 5(A) and 5(B), an example of the flow of the refrigerant flowing into the first header 39B will be described. In FIG. 5(A), the flow of the refrigerant flowing through the first header 39B is indicated by arrows F11 to F20 and arrows F18′ to F25′.

[0072] First, the gas-liquid two-phase refrigerant flows into the front chamber 75 of the first header 39B through the through-hole 51 (arrows F11 to F12). The refrigerant that has flowed in collides with the guiding wall 85 and flows in the direction back to the through-hole 51, that is, towards one side of the laminate 59 (arrow F13), flows between the end portion 85a of the guiding wall 85 and the first plate 53 (arrows F14 to F15), and then flows towards the other side of the laminate 59 (arrows F16 to F17). Next, the refrigerant collides with the second plate 55 and branches out in the horizontal direction and in two directions (arrows F18 and F18′).

[0073] One of the refrigerants branched by the second plate 55 reaches the inlet 73a of the second flow path 73 located on the other side of the laminate 59. The refrigerant that has reached the inlet 73a of the second flow path 73 flows downward through the second flow path 73 and is stored in the second rear chamber 79 (arrow F19). The refrigerant stored in the second rear chamber 79 flows into the upper heat transfer tube 43 out of the two heat transfer tubes 43 through the heat transfer tube insertion hole 61b from the second rear chamber 79 (arrow F20).

[0074] The other refrigerant branched by the second plate 55 is rebounded by the collision with the second plate 55 and reaches the inlet 69a of the first flow path 69 located on one side of the laminate 59. The refrigerant that has reached the inlet 69a of the first flow path 69 flows downward through the first flow path 69 and is stored in the first rear chamber 77 (arrows F19′ to F24′). The refrigerant stored in the first rear chamber 77 flows into the lower heat transfer tube 43 out of the two heat transfer tubes 43 through the heat transfer tube insertion hole 61a from the first rear chamber 77 (arrow F25′).

[0075] In the series of refrigerant flows from arrow F11 to F20 and from arrow F18′ to F25′, the refrigerant flow of F22′ following F11 is blocked by the guide wall 85. Therefore, the ratio of the refrigerant that immediately flows into the first flow path 69 after flowing into the front chamber 75 from the through hole 51 is greatly reduced. That is, even when the outdoor unit 5 equipped with the heat exchanger 37 is installed inclined such that the inlet 69a of the first flow path 69 is lower than the inlet 73a of the second flow path 73, the guide wall 85 reduces the influence of the inclination and suppresses the excessive inflow of the refrigerant into the first flow path 69.

[0076] In the examples of FIGS. 5(A) and 5(B), the excessive inflow of the refrigerant into the first flow path 69 is suppressed. However, when suppressing the excessive inflow of the refrigerant into the second flow path 73, for example, the guide wall 85 may be provided substantially in an inverted J shape perpendicular to the partition wall 81 of the front chamber 75 from the other side edge of the through hole 51 farther from the first flow path 69 toward one side edge of the through hole 51 in the front chamber 75.

[0077] FIG. 6(A) is an exploded perspective view of a first header 39C of a fourth example in the heat exchanger 37 according to an embodiment of the present invention, and FIG. 6(B) is a cross-sectional view of the first header 39C of the fourth example in the heat exchanger 37 according to an embodiment of the present invention.

[0078] As shown in FIGS. 6(A) and 6(B), the front chamber 75 may have an enclosure member 91 that dams up the refrigerant flowing in from the through-hole 51. In the examples of FIGS. 6(A) and 6(B), the enclosure member 91 is provided substantially perpendicular to the partition wall 81 of the front chamber 75 so as to surround the through-hole 51 in a substantially U shape from one side edge to the other side edge of the through-hole 51.

[0079] The enclosure member 91 can be configured by providing a non-through region in the first through region 63 of the plurality of intermediate plates 57.

[0080] Specifically, a pair of third non-through regions 93 are provided in the first through region 63 of the first intermediate plate 57a. The pair of third non-through regions 93 are, for example, rectangular with long sides each being a side extending in the thickness direction of the first intermediate plate 57a. The pair of third non-through regions 93 are symmetrically arranged with respect to a center line passing through the center in the short side direction of the first intermediate plate 57a and extending in the long side direction. One end face of the pair of third non-through regions 93 in the thickness direction of the first intermediate plate 57a is in contact with the surface of the first plate 53 in the vicinity of the through-hole 51.

[0081] Furthermore, a fourth non-through region 95 is provided in the first through region 63 of the second intermediate plate 57b. The fourth non-through region 95 has a recess 95a that is recessed in the thickness direction of the second intermediate plate 57b from one surface of the second intermediate plate 57b facing the first intermediate plate 57a. The recess 95a faces the through-hole 51. The fourth non-through region 95 has a pair of end portions extending in the thickness direction of the second intermediate plate 57b. One end face of the pair of end portions of the fourth non-through region 95 and the other end face of the pair of third non-through regions 93 are substantially flush and in contact with each other. Therefore, after brazing the laminate 59, the pair of third non-through regions 93 and the fourth non-through region 95 are integrated to form the enclosure member 91.

[0082] Here, an example of the flow of the refrigerant flowing into the first header 39C will be described. In FIG. 6(A), the flow of the refrigerant flowing through the first header 39C is indicated by arrows F21 to F29 and arrows F27' to F34'.

[0083] First, the gas-liquid two-phase refrigerant flows into the front chamber 75 of the first header 39C through the through holes 51 of the first plate 53 (arrows F21 and F22). The refrigerant that has flowed in is blocked by the surrounding member 91 and uniformly overflows around the surrounding member 91 (arrows F23 and F24). A part of the refrigerant that has overflowed from the surrounding member 91 collides with the second plate 55 which is the wall of the front chamber 75 and branches in two horizontal directions (arrows F25 to F27 and arrow F27').

[0084] A part of the refrigerant that has overflowed from the surrounding member 91 flows downward through the second flow path 73 located on the other side of the laminate 59 and is stored in the second rear chamber 79 (arrow F28). The refrigerant stored in the second rear chamber 79 flows into the upper heat transfer tube 43 out of the two heat transfer tubes 43 from the second rear chamber 79 through the heat transfer tube insertion hole 61b (arrow F29).

[0085] The remainder of the refrigerant that has overflowed from the surrounding member 91 merges with the flow of the refrigerant rebounded by the collision with the second plate 55 (arrow F27') and flows downward through the first flow path 69 located on one side of the laminate 59 and is stored in the first rear chamber 77 (arrows F27' to F33'). The refrigerant stored in the first rear chamber 77 flows into the lower heat transfer tube 43 out of the two heat transfer tubes 43 from the first rear chamber 77 through the heat transfer tube insertion hole 61a (arrow F34').

[0086] In the series of refrigerant flows from arrow F21 to F29 and from arrow F27' to F34', the refrigerant uniformly overflows by the enclosure member 91, and the difference between the path length of the refrigerant flowing from the enclosure member 91 to the first flow path 69 and the path length of the refrigerant flowing from the enclosure member 91 to the second flow path 73 becomes small. Therefore, the difference in the distribution amount of the refrigerant to the first flow path 69 and the second flow path 73 due to the difference in the path length through which the refrigerant flows becomes small. That is, it becomes easier to control the amount of the refrigerant flowing through the first flow path 69 and the second flow path 73.

[0087] As described above, the heat exchanger 37 according to the present embodiment includes a front chamber 75 connected to the through hole 51 of the first plate 53, a plurality of rear chambers 77, 79 arranged at intervals in the first direction from the front chamber 75 and each connected to the respective heat transfer tubes 43, and a plurality of flow paths 69, 73 for flowing the refrigerant from the front chamber 75 to the respective rear chambers 77, 79. And each of the plurality of flow paths 69, 73 has inlets 69a, 73a provided in a partition wall 81 separating the front chamber 75 and the second rear chamber 79 adjacent to the front chamber 75. Further, the air conditioner 1 according to the present embodiment includes a heat exchanger 37 in which the front chamber 75 is disposed above the plurality of rear chambers 77, 79. Therefore, during their use, the heat exchanger 37 and the air conditioner 1 branch the gas-liquid two-phase refrigerant flowing into the first header 39 from the through hole 51 from the front chamber 75 to the plurality of rear chambers 77, 79 existing below the front chamber 75 through the plurality of flow paths 69, 73 that branch downward from the front chamber 75. Therefore, compared with a heat exchanger and an air conditioner provided with a conventional laminated header having a flow path that branches vertically starting from the inflow path of the refrigerant into the header, the heat exchanger 37 and the air conditioner 1 can distribute a homogeneous refrigerant to the plurality of heat transfer tubes 43 even under gravity.

[0088] In addition, the heat exchanger 37 and the air conditioner 1 according to the present embodiment include a plurality of flow paths 69 and 73, and the opening cross-sectional areas of their inlets 69a and 73a are different from each other. Therefore, the heat exchanger 37 and the air conditioner 1 can adjust the flow rate of the refrigerant flowing through each of the flow paths 69 and 73. That is, the heat exchanger 37 and the air conditioner 1 can adjust the uniform distribution amount of the refrigerant to the plurality of heat transfer tubes 43.

[0089] In addition, the heat exchanger 37 and the air conditioner 1 according to the present embodiment include a front chamber 75 having a guide wall 85 that changes the direction of the refrigerant flowing in from the through hole 51. Therefore, even when the heat exchanger 37 and the air conditioner 1 are installed inclined from the horizontal plane and the difference in the flow rate of the refrigerant between the plurality of flow paths 69 and 73 increases due to the inclination, the guide wall 85 can change the direction of the refrigerant flow and reduce the difference in the flow rate of the refrigerant between the plurality of flow paths 69 and 73. That is, the heat exchanger 37 and the air conditioner 1 can appropriately adjust the flow rate of the refrigerant flowing through each of the plurality of flow paths 69 and 73 by the guide wall 85.

[0090] In addition, the heat exchanger 37 and the air conditioner 1 according to the present embodiment include a front chamber 75 having an enclosure member 91 that dams up the refrigerant flowing in from the through hole 51. The enclosure member 91 temporarily dams up the refrigerant and causes it to overflow uniformly in the outer peripheral direction of the enclosure member 91. Thereby, the enclosure member 91 changes the refrigerant flow from the flow starting from the through hole 51 to the flow starting from the enclosure member 91. By changing the starting point of the refrigerant flow to the enclosure member 91, the difference in the flow path length from the starting point of the refrigerant flow to the plurality of flow paths 69 and 73 is reduced. Therefore, the heat exchanger 37 and the air conditioner 1 can reduce the difference in the distribution amount of the refrigerant between the plurality of flow paths 69 and 73 due to the difference in the path length through which the refrigerant flows. That is, the heat exchanger 37 and the air conditioner 1 can make it easier to control the amount of the refrigerant flowing through the plurality of flow paths 69 and 73.

[0091] Therefore, according to the heat exchanger 37 and the air conditioner 1 according to the present embodiment, even under gravity, a homogeneous refrigerant can be distributed to a plurality of heat transfer tubes 43.

[0092] Although several embodiments of the present invention have been described, these embodiments are presented by way of example and are not intended to limit the scope of the invention. These novel embodiments can be implemented in various other forms, and various omissions, replacements, and changes can be made without departing from the gist of the invention. These embodiments and their modifications are included in the scope and gist of the invention, and are included in the invention described in the claims and the equivalent scope thereof.

Explanation of Reference Numerals

[0093] 1... air conditioner, 3... indoor unit, 5... outdoor unit, 11... indoor unit housing, 13... indoor heat exchanger, 15... indoor blower, 21... outdoor unit housing, 23... compressor, 25... four-way valve, 27... outdoor heat exchanger, 29... expansion mechanism, 31... outdoor blower, 33... refrigerant pipe, 37... heat exchanger, 39, 39A, 39B, 39C... header (first header), 41... header (second header), 43... heat transfer tube, 45... plate fin, 51... through hole, 53... first plate, 55... second plate, 57... intermediate plate, 57a... first intermediate plate, 57b... second intermediate plate, 57c... third intermediate plate, 59... laminate, 61... heat transfer tube insertion hole, 61a... heat transfer tube insertion hole, 61b... heat transfer tube insertion hole, 63... first through region, 65... second through region, 67... third through region, 69... first flow path, 69a, 73a... inlet, 71... fourth through region, 72... fifth through region, 73... second flow path, 75... front chamber, 77... first rear chamber, 79... second rear chamber, 81... partition wall, 83... second recess, 85... guide wall, 85a... end, 87... first non-through region, 89... second non-through region, 89a... recess, 91... surrounding member, 93... third non-through region, 95... fourth non-through region, 95a... recess.

Claims

1. A plurality of heat transfer tubes arranged at intervals in a first direction and having refrigerant flow paths through which refrigerant flows; A first header connected to at least one end in the extending direction of the plurality of heat transfer tubes and configured to circulate the refrigerant through the refrigerant flow paths. The first header has a laminate formed by laminating a first plate having a through hole for introducing the refrigerant, a second plate to which the plurality of heat transfer tubes are connected, and a plurality of intermediate plates disposed between the first plate and the second plate. The laminate includes: A front chamber connected to the through hole of the first plate; A plurality of rear chambers arranged at intervals from the front chamber in the first direction and each connected to a corresponding one of the heat transfer tubes; A plurality of flow paths for introducing the refrigerant from the front chamber into each of the rear chambers. Each of the plurality of flow paths has an inlet provided in a partition wall separating the front chamber and the rear chamber adjacent to the front chamber, and is a heat exchanger.

2. The heat exchanger according to claim 1, wherein the opening cross-sectional areas of the inlets of the plurality of flow paths are different from each other.

3. The heat exchanger according to claim 1, wherein the front chamber has a guide wall for changing the direction of the flow of the refrigerant flowing in from the through hole.

4. The heat exchanger according to claim 1, wherein the front chamber has an enclosure member for blocking the refrigerant flowing in from the through hole.

5. An air conditioner comprising the heat exchanger according to any one of claims 1 to 4, wherein the front chamber is disposed above the plurality of rear chambers.

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