HEAT EXCHANGER UNIT AND AIR CONDITIONER USING SAME

Abstract

 Heat exchanger unit (100) includes a plurality of heat exchangers (1). Each of a plurality of heat exchangers (1) includes first pipe (6) into which refrigerant flows, a first header flow channel that communicates with an outflow side of first pipe (6), a second header flow channel disposed downstream of the first header flow channel, a plurality of refrigerant flow channels that allow the first header flow channel and the second header flow channel to communicate with each other, and second pipe (7) that communicates with an outflow side of the second header flow channel. Heat exchanger unit (100) also includes first flow rate adjuster (81) provided in first pipe (6) of at least one of a plurality of heat exchangers (1), and second flow rate adjuster (82) provided in second pipe (7) of at least one of a plurality of heat exchangers (1).

Description

TECHNICAL FIELD

[0001] The present disclosure relates to a heat exchanger unit configured of a plurality of heat exchangers connected in parallel, and an air conditioner using the same. In particular, the present invention relates to a heat exchanger unit suitable for a case where the heat exchangers are plate fin stacked-type heat exchangers, and an air conditioner using the same.

BACKGROUND ART

[0002] Generally, an air conditioner performs cooling or heating by circulating refrigerant, compressed by a compressor, through a heat exchanger such as a condenser and an evaporator to exchange heat with air. As the heat exchanger, in addition to a case where one heat exchanger is used alone, a unit obtained by combining a plurality of heat exchangers may be used. In such a case, it is preferable to make refrigerant almost uniformly flow through respective heat exchangers so that the heat exchange efficiencies of the respective heat exchangers become almost the same.

[0003] Therefore, a conventional heat exchanger unit is configured such that refrigerant is distributed via a distributor and the refrigerant is supplied to the heat exchangers almost equally (for example, see Patent Literature 1).

[0004] FIG. 13 shows a schematic configuration of a conventional heat exchanger unit described in Patent Literature 1. Three heat exchangers 101 are connected in parallel, and distributor 102 is provided at a refrigerant branch portion. Further, flow rate adjuster 103 is provided between distributor 102 and an inlet pipe portion of heat exchanger 101 on the downstream side thereof. Then, refrigerant is distributed by distributor 102. Then, flow rate adjuster 103 adjusts the flow rate of the refrigerant, that is, a loss of pressure (hereinafter, referred to as a pressure loss), and the refrigerant is supplied to respective heat exchangers 101.

[0005] With the configuration described above, the refrigerant is supplied to respective heat exchangers 101 almost uniformly.

[0006] In the configuration described in Patent Literature 1, a flow rate of the refrigerant distributed by distributor 102 is adjusted by flow rate adjuster 103 and the refrigerant flows into respective heat exchangers 101. However, if a pressure loss of each outlet pipe is different, a degree of dryness at an inlet port varies between a plurality of heat exchangers 101, resulting in a difference in the distributed amount. Therefore, the refrigerant may not be equally distributed to the heat exchangers. That is, if flow rate adjustment, in other words, pressure loss adjustment, is performed at the heat exchanger inlet portion by flow rate adjuster 103, equalization of distribution is improved as compared with a case where the pressure loss adjustment is not performed. However, a degree of equalization of the distribution is still insufficient, and there is room for improvement.

Citation List

Patent Literature

[0007] PTL 1: Japanese Patent No. 6104893

SUMMARY OF THE INVENTION

[0008] The present disclosure provides a heat exchanger unit that improves a degree of equalization when refrigerant is distributed to a plurality of heat exchangers and exhibits good heat exchange performance, and a high-performance air conditioner using the same.

[0009] Specifically, a heat exchanger unit of the present disclosure is a heat exchanger unit including a plurality of heat exchangers. Each of the plurality of the heat exchangers includes a first pipe into which refrigerant flows, a first header flow channel that communicates with an outflow side of the first pipe, a second header flow channel disposed downstream of the first header flow channel, a plurality of refrigerant flow channels that allow the first header flow channel and the second header flow channel to communicate with each other, and a second pipe that communicates with an outflow side of the second header flow channel. The heat exchanger unit also includes a distribution part that distributes the refrigerant to the first pipe in each of the plurality of the heat exchangers, a merging part that merges the refrigerant from the second pipe in each of the plurality of the heat exchangers, a first flow rate adjuster provided to the first pipe in at least one of the plurality of the heat exchangers, and a second flow rate adjuster provided to the second pipe in at least one of the plurality of the heat exchangers.

[0010] Thereby, by adjusting the flow rate adjuster so that a pressure loss on an inlet side and a pressure loss on an outlet side of each heat exchanger become substantially equal, it is possible to distribute the refrigerant to respective heat exchangers by making the degree of dryness and the circulation amount of the refrigerant substantially equal. Therefore, the degree of equalization of distribution of the refrigerant between the heat exchangers can be improved. That is, the heat exchange performance of the entire heat exchanger unit can be improved by ensuring equal distribution of the refrigerant to respective heat exchangers and equalizing the heat exchange efficiency between the heat exchangers.

BRIEF DESCRIPTION OF DRAWINGS

[0011] 

FIG. 1 is a diagram illustrating a schematic configuration of a heat exchanger unit according to a first exemplary embodiment of the present disclosure.

FIG. 2 is an exploded perspective view of a heat exchanger of the heat exchanger unit in FIG. 1 as viewed from below.

FIG. 3 is a plan view of plate fins constituting a heat exchanger of the heat exchanger unit in FIG. 1.

FIG. 4 is an exploded perspective view showing a part of the plate fin in FIG. 3 in an enlarged manner.

FIG. 5 is a perspective view showing a cross section of a refrigerant flow channel portion in the heat exchanger of the heat exchanger unit in FIG. 1.

FIG. 6 is a perspective view showing a cross section of a header flow channel portion of the heat exchanger in FIG. 5.

FIG. 7 is a diagram illustrating a schematic configuration of a heat exchanger unit according to a second exemplary embodiment of the present disclosure.

FIG. 8 is a diagram showing a schematic configuration of a portion indicated by "a" in FIG. 7.

FIG. 9 is a refrigeration cycle diagram of an air conditioner according to a third exemplary embodiment of the present disclosure.

FIG. 10 is a diagram showing a cross-sectional configuration of the air conditioner according to the third exemplary embodiment when viewed from a right side.

FIG. 11 is a diagram showing a cross-sectional configuration of the air conditioner according to the third exemplary embodiment when viewed from above.

FIG. 12 is a diagram showing an arrangement configuration of a heat exchanger of the air conditioner according to the third exemplary embodiment.

FIG. 13 is a diagram showing a schematic configuration of a conventional heat exchanger unit.

DESCRIPTION OF EMBODIMENTS

(Knowledge underlying the present disclosure)

[0012] The inventors of the present invention have earnestly studied distribution of refrigerant to a plurality of heat exchangers, and have obtained the following knowledge.

[0013] According to experiments performed by the inventors of the present invention, in a case of a heat exchanger having a small internal pressure loss of the heat exchanger itself such as a multi-path type small-diameter heat exchanger, it is found that a degree of equalization of distribution of refrigerant is low between the heat exchangers. Therefore, it is necessary to improve the degree of equalization of distribution by some kind of method.

[0014] As one of multi-pass small-diameter heat exchangers, for example, there is a plate fin stacked-type heat exchanger. In a plate fin stacked-type heat exchanger, a diameter of a heat transfer path between a header at an inlet portion and a header at an outlet portion can be easily reduced, and a number of heat transfer channels (a number of paths) can be increased. Therefore, when it is used as an indoor heat exchanger of an air conditioner, a great advantageous effect can be obtained.

[0015] However, when the inventors of the present invention connect a plurality of the plate fin stacked-type heat exchangers in parallel, provide a flow rate adjuster on an inlet side of each heat exchanger so as to equalize the pressure loss of the inlet pipe between the plurality of heat exchangers, if the pressure loss is different between the heat exchangers due to a difference in the length of outlet pipes or the like, it is not possible to realize uniform distribution of the refrigerant to the respective heat exchangers. The inventors of the present invention have considered a cause as follows. That is, in a multi-path small-diameter heat exchanger such as a plate fin stacked-type heat exchanger, even if a flow rate is adjusted at an inlet port of the heat exchanger, an internal pressure loss of the heat exchanger itself is extremely small. Therefore, if a pressure loss generated in the outlet pipe differs between the plurality of heat exchangers, the difference will affect the degree of dryness of the refrigerant at the inlet port of the heat exchanger. Then, as a result, a degree of equalization in distribution of the refrigerant is low, so that uniform distribution cannot be realized.

[0016] For this reason, even though an attempt is made to improve heat exchange efficiency of a heat exchanger by using a plate fin stacked-type heat exchanger that is advantageous in reducing the diameter of a heat transfer channel and increasing a number of heat transfer channels (a number of paths), an effect of improving the heat exchange efficiency by reducing the diameter of the heat transfer channel and increasing the number of heat transfer channels (the number of paths) cannot be fully utilized, and good heat exchange performance cannot be obtained.

[0017] Here, as described in Patent Literature 1, when a heat exchanger unit in which a plurality of heat exchangers are combined is used as an outdoor unit, since a plurality of heat exchangers face different air outlets respectively, there is no problem even if the heat exchange efficiency is slightly different between the plurality of heat exchangers. On the other hand, when a heat exchanger unit in which a plurality of heat exchangers are combined in parallel is used to face one air outlet as an indoor unit, the difference in the heat exchange efficiency between the heat exchangers is directly linked to the difference in air temperature. Therefore, a user feels uncomfortable. Therefore, it is necessary to further increase the degree of equalization of distribution to the respective heat exchangers.

[0018] Based on the new findings described above, the inventors of the present invention have made the following disclosure.

[0019] A heat exchanger unit according to an aspect of the present disclosure is a heat exchanger unit including a plurality of heat exchangers. Each of the plurality of the heat exchangers includes a first pipe into which refrigerant flows, a first header flow channel that communicates with an outflow side of the first pipe, a second header flow channel disposed downstream of the first header flow channel, a plurality of refrigerant flow channels that allow the first header flow channel and the second header flow channel to communicate with each other, and a second pipe that communicates with an outflow side of the second header flow channel. The heat exchanger unit also includes a distribution part that distributes the refrigerant to the first pipe in each of the plurality of the heat exchangers, a merging part that merges the refrigerant from the second pipe in each of the plurality of the heat exchangers, a first flow rate adjuster provided to the first pipe of at least one of the plurality of the heat exchangers, and a second flow rate adjuster provided to the second pipe of at least one of the plurality of the heat exchangers.

[0020] Thereby, by adjusting the flow rate adjuster so that a pressure loss on the inlet side and a pressure loss on the outlet side of each heat exchanger become equal, the refrigerant can be distributed to respective heat exchangers by making the degree of dryness and the circulation amount of the refrigerant equal. Therefore, the degree of equalization of branch flows of the refrigerant between the heat exchangers can be increased. In other words, the heat exchange performance of the entire heat exchanger unit can be improved by ensuring equal distribution of the refrigerant to the respective heat exchangers to thereby equalize the heat exchange efficiency.

[0021] In a heat exchanger unit according to another aspect of the present disclosure, each of the plurality of the heat exchangers is a plate fin stacked-type heat exchanger including a plurality of plate fins. Each of the plurality of the plate fins includes two plate members stacked, and the plurality of the refrigerant flow channels are formed of a dented groove formed on at least one of the two plate members. Each of the plurality of the plate fins may have a header region in which at least one of the first header flow channel and the second header flow channel is arranged.

[0022] This makes it possible to reduce the diameter of a heat transfer channel between the upstream first header flow channel and the downstream second header flow channel, to thereby increase the number of paths. Therefore, a heat exchanger having a small internal pressure loss of the heat exchanger itself can be obtained. In addition, even in the case where the internal pressure loss of the heat exchanger itself is small as described above, it is possible to adjust the flow rate adjuster so as to make the pressure loss on the inlet side and the pressure loss on the outlet side equal between the respective heat exchangers. Therefore, it is possible to distribute the refrigerant to the respective heat exchangers while making the degree of dryness and the circulation amount of the refrigerant equal. Thereby, the heat exchange efficiency of the respective heat exchangers can be equalized, and the heat exchange efficiency of the entire heat exchanger unit can be improved.

[0023] A heat exchanger unit according to another aspect of the present disclosure may have a configuration in which a distributor is provided to a distribution part for the refrigerant.

[0024] Thereby, the refrigerant can be distributed substantially evenly to a plurality of the heat exchangers connected in parallel, and the heat exchange efficiency of the entire heat exchanger unit can be improved.

[0025] A heat exchanger unit according to another aspect of the present disclosure may have a configuration in which a branch pipe is provided to a distribution part for refrigerant, and a throttle pipe having a pipe diameter smaller than a pipe diameter at an inlet port of the branch pipe is provided upstream of the branch pipe.

[0026] Thereby, the flow velocity of the refrigerant is accelerated by the throttle pipe, and the refrigerant acts so that the flow of the refrigerant immediately after the throttle pipe becomes an annular flow. Therefore, since such refrigerant flows from the inlet port of the branch pipe, the refrigerant can be distributed with substantially the same gas-liquid balance and supplied to the respective heat exchangers. Therefore, the heat exchange efficiency of the respective heat exchangers can be made substantially uniform, and the heat exchange efficiency of the entire heat exchanger unit can be made good.

[0027] An air conditioner according to an aspect of the present disclosure is an air conditioner including an indoor unit and an outdoor unit. At least one of the indoor unit and the outdoor unit has the heat exchanger unit described above.

[0028] Thus, a high-performance air conditioner with high energy saving property, having a heat exchanger unit with high heat exchange efficiency, can be obtained.

[0029] In an air conditioner according to another aspect of the present disclosure, the indoor unit includes a housing, a heat exchanger unit disposed in the housing, an air passage configured in the housing, and an air outlet disposed at an outlet port of the air passage. Then, a plurality of the heat exchangers of the heat exchanger unit may be configured to be arranged side by side in an air passage along a first direction across the air passage.

[0030] Thereby, even when a plurality of heat exchangers are arranged side by side, the temperature of the air blown out of the air outlet of the indoor unit can be made substantially uniform. Therefore, it is possible to obtain a high-efficiency and high-quality air conditioner in which the heat exchange performance is improved by using a fin-stacked heat exchanger having high heat exchange efficiency and the temperature unevenness of the air from the air outlet is small.

[0031] In an air conditioner according to another aspect of the present disclosure, the distribution part and the merging part are disposed outside one end of the plurality of the heat exchangers arranged side by side in the first direction, and in each of the plurality of the heat exchangers, the first pipe and the second pipe are disposed in a projection range of a header region projected to a plane perpendicular to a direction of air flowing through the air passage, or a plane which is vertical and is parallel to the first direction.

[0032] Thereby, of the heat exchangers arranged side by side across the air passage, the first pipe and the second pipe connected to the upstream header flow channel and the downstream header flow channel of the heat exchanger, located on the opposite side away from the merging part, cross the air passage. However, the first pipe and the second pipe that cross the air passage are located in a header region where at least one of the upstream header flow channel and the downstream header flow channel of the heat exchanger is provided and that is not subjected to heat exchange. For this reason, it is possible to suppress a decrease in the heat exchange efficiency due to the first pipe and the second pipe crossing the air passage. Therefore, a high-performance air conditioner with high energy saving property can be obtained by utilizing the high heat exchange efficiency of the heat exchanger.

[0033] Hereinafter, exemplary embodiments of the present disclosure will be described with reference to the drawings. In the exemplary embodiments, a plate fin stacked-type heat exchanger to which the present disclosure is most effectively applied will be described as an example. However, the present disclosure is not limited to this. A configuration of a heat exchanger equivalent to a technical idea described in exemplary embodiments provided below is also included.

(First exemplary embodiment)

[1-1. Configuration]

[0034] FIG. 1 is a diagram illustrating a schematic configuration of a heat exchanger unit according to a first exemplary embodiment of the present disclosure.

[0035] As shown in FIG. 1, heat exchanger unit 100 of the present exemplary embodiment includes a plurality of heat exchangers 1 (in the present exemplary embodiment, two heat exchangers 1a, 1b). Heat exchangers 1a, 1b are arranged side by side in a left-right direction (first direction) in FIG 1.

[0036] Each of heat exchangers 1a, 1b includes first header flow channel 28, second header flow channel 29 disposed downstream of the first header flow channel, and a plurality of refrigerant flow channels 31 that allow the first header flow channel and the second header flow channel to communicate with each other, as described below (see FIG. 3).

[0037] As shown in FIG. 1, heat exchangers 1a, 1b have inflow pipes 6a, 6b communicating with first header flow channel 28 (see FIG. 3) via inlet pipes 2a, 2b, respectively. Further, heat exchangers 1a, 1b have outflow pipes 7a, 7b communicating with second header flow channel 29 (see FIG. 3) via outlet pipes 3a, 3b, respectively. Inlet pipe 2a and inflow pipe 6a, and inlet pipe 2b and inflow pipe 6b constitute first pipes in heat exchangers 1a, 1b, respectively. Outlet pipe 3a and outflow pipe 7a, and outlet pipe 3b and outflow pipe 7b constitute second pipes in heat exchangers 1a, 1b, respectively.

[0038] Heat exchanger unit 100 also includes distributer (distribution part) 4 that distributes refrigerant to first pipes 6a, 6b in heat exchangers 1a, 1b, respectively, and merging unit (merging part) 5 that merges refrigerant from second pipes 7a, 7b in heat exchangers 1a, 1b, respectively. Thereby, heat exchanger unit 100 is configured such that refrigerant flowing from main pipe 70 into heat exchanger unit 100 flows in parallel in heat exchangers 1a, 1b. In other words, refrigerant circuits of heat exchangers 1a, 1b are connected to each other in parallel.

[0039] For example, when heat exchangers 1a, 1b are used as evaporators, refrigerant is distributed by distributer 4 and flows into first pipes 6a, 6b, and the refrigerant flowing through second pipes 7a, 7b are merged by merging unit 5. The refrigerant is supplied from main pipe 70 to heat exchanger unit 100, flows out of heat exchanger unit 100, and returns to main pipe 70.

[0040] In the present exemplary embodiment, as shown in FIG. 1, heat exchangers 1a, 1b are configured to be symmetric to each other with respect to a boundary portion, that is, to have a mirror image relationship.

[0041] Further, flow rate adjuster 81 is provided to the first pipe of at least one of a plurality of heat exchangers 1a, 1b. Further, flow rate adjuster 82 is provided to the second pipe of at least one of a plurality of heat exchangers 1a, 1b. That is, heat exchanger unit 100 is provided with at least one flow rate adjuster on both the upstream side and the downstream side of heat exchanger 1.

[0042] In the present exemplary embodiment, flow rate adjuster 81 and flow rate adjuster 82 are provided to inflow pipe 6 and outflow pipe 7, respectively, of a heat exchanger, of heat exchangers 1a, 1b, having a smaller pressure loss from the distributer 4 to the merging unit 5 including the heat exchanger. In the example shown in FIG. 1, the pressure loss of heat exchanger 1b on the right side is smaller than the pressure loss of heat exchanger 1a on the left side. Therefore, flow rate adjuster 81 is provided to inflow pipe 6b and flow rate adjuster 82 is provided to outflow pipe 7b of heat exchanger 1b on the right side.

[0043] Flow rate adjuster 81 is configured of, for example, a small-diameter pipe having a pipe diameter smaller than a pipe diameter of inflow pipe 6. In addition, flow rate adjuster 82 is configured of, for example, a small-diameter pipe having a pipe diameter smaller than a pipe diameter of outflow pipe 7. Flow rate adjuster 81 is configured such that respective pipe pressure losses in inlet pipes 2a, 2b, from two left and right heat exchangers 1a, 1b to distributer 4, are substantially equal. Similarly, flow rate adjuster 82 is configured such that respective pipe pressure losses in outlet pipes 3a, 3b, from two left and right heat exchangers 1a, 1b to merging unit 5, are substantially equal. It should be noted that flow rate adjuster 81 may be configured of a large diameter pipe having a pipe diameter larger than a pipe diameter of inflow pipe 6 so that pipe pressures in inlet pipes 2a, 2b from heat exchangers 1a, 1b to merging unit 5 are substantially equal. Further, flow rate adjuster 82 may be configured of a large diameter pipe having a pipe diameter larger than a pipe diameter of outflow pipe 7 so that pipe pressure losses in outlet pipes 3a, 3b from heat exchangers 1a, 1b to merging unit 5 are substantially equal. That is, for the first pipe and the second pipe, flow rate adjuster 81 and flow rate adjuster 82 each can be configured by making a pipe diameter in one part different from a pipe diameter in another part.

[0044] Note that the present exemplary embodiment has shown a case where flow rate adjuster 81 and flow rate adjuster 82 are provided only to a heat exchanger, of a plurality of heat exchangers 1a, 1b, in which a pressure loss from distributer 4 to merging unit 5 including heat exchangers 1a, 1b is smaller. However, flow rate adjuster 81 and flow rate adjuster 82 may be provided to inflow pipes 6a, 6b and outflow pipes 7a, 7b of respective heat exchangers 1a, 1b. That is, the pressure loss may be adjusted for each of a plurality of heat exchangers 1a, 1b.

[0045] FIG. 2 is an exploded perspective view of a heat exchanger of the heat exchanger unit in FIG. 1 as viewed from below.

[0046] In the present exemplary embodiment, heat exchanger 1 (1a, 1b) of heat exchanger unit 100 is a plate fin stacked-type heat exchanger.

[0047] As shown in FIG. 2, heat exchanger 1 includes a plate fin stacked body 22 formed by stacking a plurality of plate fins 21, inlet pipe 2 serving as an inlet port for refrigerant, and outlet pipe 3 serving as an outlet port for refrigerant.

[0048] In inlet pipe 2 and outlet pipe 3, directions in which refrigerant flows in and out are reversed between a case where heat exchangers 1a and 1b are used as evaporators and a case where they are used as condensers. In the present exemplary embodiment, a case where heat exchangers 1a and 1b are used as evaporators will be described as an example. Therefore, description will be given by specifying that inlet pipes 2a, 2b are the first pipes and outlet pipes 3a, 3b are the second pipes.

[0049] Plate fin 21 has a rectangular plate shape. End plates 23 and 24 are provided on both sides (left side and right side in FIG. 2) in a stacking direction of plate fin stacked body 22. Each of end plates 23, 24 is formed of a flat plate. A shape of end plate 23, 24 in plan view is substantially the same as a shape of plate fin 21 in plan view shown in FIG. 3. End plate 23, 24 is formed of a rigid plate material. End plate 23, 24 is formed by, for example, metal working of a metal material such as aluminum, an aluminum alloy, and stainless steel by grinding.

[0050] End plates 23, 24 and a plurality of plate fins 21 are joined and integrated by brazing in a state where they are stacked.

[0051] Further, in the present exemplary embodiment, each of end plates 23, 24 on both sides of plate fin stacked body 22 is connected to and fixed to plate fin stacked body 22 by connection means 25 such as a bolt and a nut or a caulking pin shaft. Connection means 25 connects end plates 23, 24 to plate fin stacked body 22 at both ends in a longitudinal direction of end plates 23, 24 in plan view. That is, end plates 23, 24 on both sides of plate fin stacked body 22 are mechanically connected to and fixed to plate fin stacked body 22 while sandwiching plate fin stacked body 22.

[0052] FIG. 3 is a plan view of plate fins constituting a heat exchanger of the heat exchanger unit in FIG. 1.

[0053] FIG. 4 is an exploded perspective view showing a part of the plate fin in FIG. 3 in an enlarged manner.

[0054] As shown in FIG. 3, plate fin 21 has refrigerant flow channel 31. Refrigerant flow channel 31 is configured of a plurality of refrigerant flow channels (first refrigerant flow channel 31a and second refrigerant flow channel 31b) that are arranged in parallel with each other and through which refrigerant as a first fluid flows. That is, refrigerant flow channel 31 is configured of a group of first refrigerant flow channels 31a and second refrigerant flow channels 31b. Refrigerant flow channel 31 is disposed in a substantially U shape. Specifically, in FIG. 3, refrigerant flows from the left side to the right side in first refrigerant flow channel 31a, turns back at the right end, and flows from the right side to the left side in second refrigerant flow channel 31b. Inlet pipe 2 and outlet pipe 3 connected thereto are collectively disposed on one end side in a longitudinal direction of end plate 23a on one side (the right side in FIG. 2) of plate fin stacked body 22.

[0055] As shown in FIG. 3, plate fin 21 has a plurality of heat transfer channels (hereinafter, referred to as refrigerant flow channels 31) arranged in parallel. Refrigerant flow channel 31 is connected to upstream header flow channel (first header flow channel) 28 and downstream header flow channel (second header flow channel) 29. Upstream header flow channel 28 and downstream header flow channel 29, connected to a plurality of refrigerant flow channels 31, are collectively disposed on one end side in the longitudinal direction of plate fin 21. Upstream header flow channel 28 and downstream header flow channel 29 may be arranged separately on both ends in the longitudinal direction of plate fin 21.

[0056] Further, as shown in FIG. 3, a region where the header flow channel is disposed is referred to as header region H, and a region where refrigerant flow channel 31 is disposed is referred to as flow channel region P.

[0057] Upstream header flow channel 28 serves as an inlet port for refrigerant when heat exchanger 1 is used as an evaporator, and serves as an outlet port for refrigerant when heat exchanger 1 is used as a condenser. On the other hand, downstream header flow channel 29 is opposite. That is, when heat exchanger 1 is used as an evaporator, downstream header flow channel 29 serves as an outlet port for refrigerant, and when heat exchanger 1 is used as a condenser, downstream header flow channel 29 serves as an inlet port for refrigerant.

[0058] As shown in FIG. 4, plate fin 21 is configured such that a pair of first plate member 26a and second plate member 26b are disposed to face each other and joined to each other by brazing. A plurality of refrigerant flow channels 31 are formed in a substantially U-shape as described above.

[0059] FIG. 5 is a perspective view showing a cross section of a refrigerant flow channel portion in a heat exchanger of the heat exchanger unit in FIG. 1.

[0060] FIG. 6 is a perspective view showing a cross section of a header flow channel portion of the heat exchanger in FIG. 5.

[0061] As shown in FIGS. 5 and 6, a large number of the plate fins 21 are stacked to form a plate fin stacked body 22 that is a main body of heat exchanger 1.

[0062] Plate fin 21 is provided with a plurality of protrusions 27 (see FIG. 3) as appropriate at both ends in the longitudinal direction of plate fin 21 in plan view and between refrigerant flow channels 31. Gap d (see FIGS. 5 and 6) is formed between plate fins 21 by a plurality of protrusions 27, and air as a second fluid flows through gap d.

[0063] Refrigerant flow channel 31 is formed of dented grooves formed in first plate member 26a and second plate member 26b. Therefore, a diameter of refrigerant flow channel 31 can be easily reduced. Note that refrigerant flow channel 31 may be configured of a dented groove provided in at least one of first plate member 26a and second plate member 26b.

[0064] In addition, refrigerant flow channel 31 includes upstream header flow channel-side refrigerant flow channel (first refrigerant flow channel) 31a connected to upstream header flow channel 28, and downstream header flow channel-side refrigerant flow channel (second refrigerant flow channel) 31b connected to downstream header flow channel 29. In the present exemplary embodiment, first header flow channel 28 and first refrigerant flow channel 31a communicate with each other via passage 34a, and second header flow channel 29 and second refrigerant flow channel 31b communicate with each other via passage 34b.

[0065] Slit groove 35 (see FIG. 3) is disposed between first refrigerant flow channel 31a and second refrigerant flow channel 31b. As shown in FIG. 3, slit groove 35 extends from an end (left side in FIG. 3) of plate fin 21 on a side where upstream header flow channel 28 and downstream header flow channel 29 are disposed, to the vicinity of a folded portion of refrigerant flow channel 31. Slit groove 35 can prevent direct heat transfer between first refrigerant flow channel 31a and second refrigerant flow channel 31b.

[0066] Further, a number of second refrigerant flow channels 31b is larger than a number of first refrigerant flow channels 31a. Further, non-porous portion 36 is disposed at a portion of downstream header flow channel 29 facing passage 34b, and does not constitute a refrigerant flow channel. Thereby, when heat exchanger 1 is used as a condenser, the refrigerant flowing from downstream header flow channel 29 to second refrigerant flow channel 31b collides with wall 36a of non-porous portion 36, and evenly flows to second refrigerant flow channel 31b.

[1-2. Operation]

[0067] Operation and action of heat exchanger unit 100 configured as described above will be described.

[0068] Here, a case where heat exchangers 1a and 1b of heat exchanger unit 100 are used as evaporators will be described.

[0069] Refrigerant that is the first fluid flows into heat exchangers 1a, 1b from inlet pipes 2a, 2b provided on the respective inlet sides (upstream sides) of heat exchangers 1a, 1b. The refrigerant flows into first refrigerant flow channels 31a respectively provided to a plurality of plate fins 21 constituting plate fin stacked body 22 via upstream header flow channel 28. The refrigerant flows through a plurality of first refrigerant flow channels 31a in parallel in the longitudinal direction, turns around in a U-turn, and flows through a plurality of second refrigerant flow channels 31b in parallel in the longitudinal direction. After that, the refrigerant flows through downstream header flow channel 29 and flows out through outlet pipes 3a, 3b provided on the outlet side (downstream side) of heat exchangers 1a, 1b.

[0070] On the other hand, air (second fluid) that exchanges heat with the refrigerant (first fluid) passes through gap d (see FIGS. 5 and 6) formed between plate fins 21 constituting plate fin stacked body 22. Thereby, heat exchange between the refrigerant as the first fluid and the air as the second fluid is performed.

[0071] In this way, heat exchangers 1a, 1b perform heat exchange between the refrigerant and the air. Further, the refrigerant is distributed by distributer 4 on the inlet side (upstream side) of heat exchanger 1, and supplied into heat exchangers 1a, 1b from two inlet pipes 2a, 2b, respectively. Then, the refrigerant that has passed through heat exchangers 1a, 1b is discharged from outlet pipes 3a, 3b, and is then merged by merging unit 5.

[0072] Here, when a plurality of (two in the present exemplary embodiment) heat exchangers 1 are used while being disposed in parallel, the refrigerant is distributed to respective heat exchangers. At this time, it is desirable that the refrigerant flowing into heat exchangers 1a, 1b has the same degree of dryness. Further, it is desirable that the flow rate of the refrigerant flowing into each heat exchanger is equal.

[0073] However, when the lengths of inflow pipes 6 in heat exchangers 1a, 1b are different from each other, or when the lengths of outflow pipes 7 in heat exchangers 1a, 1b are different from each other, pressure losses in heat exchangers 1a, 1b may be different from each other. For this reason, when distributer 4, merging unit 5, and heat exchangers 1a, 1b are arranged in such a manner, there is a concern that balance in the degree of dryness and the flow rate of the refrigerant flowing into respective heat exchangers may be lost.

[0074] For example, in the above-described conventional example, pressure is adjusted by a flow rate adjuster provided only on the inlet pipe side, that is, on the upstream side of a heat exchanger. In the above-described conventional example, since a pressure loss in refrigerant flow channel 31 in the used heat exchanger is extremely small, the refrigerant flowing into the inlet pipe is affected by a difference in pipe pressure on the outlet pipe side (downstream side). Therefore, the degree of dryness of the refrigerant flowing into each heat exchanger is different for each heat exchanger. Therefore, the refrigerant cannot be distributed in such a manner that the flow rate of the refrigerant flowing into respective heat exchangers is equalized. That is, the degree of equalization at the time of distributing the inflow refrigerant is low, and the inflow refrigerant is not evenly distributed to respective heat exchangers.

[0075] On the other hand, in the present exemplary embodiment, flow rate adjuster 82 is provided not only on the upstream side of heat exchangers 1a and 1b, but also on the side of outlet pipes 3a, 3b (downstream side). That is, pressure is adjusted on both the inlet side and the outlet side of heat exchangers 1a, 1b. Thereby, the pressure loss on the inlet side of the heat exchangers 1a, 1b can be equalized, and also the pressure loss on the outlet side of the heat exchangers 1a, 1b can be equalized. Therefore, the state of refrigerant at each of the inlet ports of the heat exchangers 1a, 1b, that is, the degree of dryness of the refrigerant, can be made equal. Thereby, the refrigerant can be equally distributed to a plurality of heat exchangers 1a, 1b. That is, it is possible to distribute the refrigerant by greatly improving the equalization ratio of the distributed refrigerant, and allow the refrigerant to flow evenly into heat exchangers 1a, 1b.

[0076] Therefore, equalization of the heat exchange efficiency in heat exchangers 1a, 1b can be increased, and the heat exchange performance of the entire heat exchanger unit can be improved.

[0077] The plate fin stacked-type heat exchanger exemplified in the present exemplary embodiment has a large number of first refrigerant flow channels 31a and second refrigerant flow channels 31b that connect upstream header flow channel 28 and downstream header flow channel 29 (a number of paths is large). Therefore, the pressure loss in entire refrigerant flow channel 31, that is, the internal pressure loss as a heat exchanger, is as low as about one tenth of the internal pressure loss of a fin tube-type heat exchanger. Therefore, even when the pressure on the side of inlet pipes 2a, 2b (upstream side) is adjusted, the degree of dryness of the refrigerant flowing from inlet pipes 2a, 2b is different between heat exchangers 1a, 1b under the influence of a difference in pipe pressure on the side of outlet pipes 3a, 3b (downstream side). Therefore, the refrigerant cannot be evenly distributed to a plurality of heat exchangers 1a, 1b.

[0078] However, in the present exemplary embodiment, flow rate adjuster 82 is also provided on the side of outlet pipes 3a, 3b (downstream side). Thereby, the pressure can be adjusted not only at the refrigerant inlet side but also at the outlet side. Therefore, not only the pressure loss on the inlet side of the heat exchangers 1a, 1b can be made equal but also the pressure loss on the outlet side can be made equal. Thereby, the degree of dryness of the refrigerant flowing into heat exchangers 1a, 1b can be made equal, so that the refrigerant can be evenly distributed to heat exchangers 1a, 1b.

[0079] Accordingly, even when plate fin stacked-type heat exchangers are used as a plurality of heat exchangers 1a, 1b constituting heat exchanger unit 100 as in the present exemplary embodiment, it is possible to improve the degree of equalization of the distributed refrigerant flowing into respective heat exchanger 1a, 1b to thereby improve the heat exchange performance of the entire heat exchanger unit.

[0080] As described above, with use of plate fin stacked-type heat exchangers as heat exchangers 1a, 1b, the heat exchange efficiency in heat exchangers 1a, 1b can be improved by reducing a diameter of refrigerant flow channel 31 between upstream header flow channel 28 and downstream header flow channel 29 and increasing a number of paths of refrigerant flow channel 31. Further, heat exchanger unit 100 of the present exemplary embodiment can distribute the refrigerant evenly to a plurality of pipes communicating with a plurality of heat exchangers 1a, 1b and allow the refrigerant to flow into heat exchangers 1a, 1b. Therefore, heat exchanger unit 100 having good heat exchange performance can be realized.

[1-3. Effects and others]

[0081] As described above, in the present exemplary embodiment, heat exchange unit 100 includes heat exchanger 1a and heat exchanger 1b, and includes a distributer 4 that is connected to main pipe 70 for supplying the refrigerant and distributes the refrigerant to first pipe 6a and first pipe 6b, a second pipe 7a that supplies the refrigerant supplied from heat exchanger 1a to main pipe 70, a second pipe 7b that supplies the refrigerant supplied from heat exchanger 1b to main pipe 70, and a merging unit 5 that is connected to second pipe 7a, second pipe 7b, and main pipe 70 and supplies the refrigerant supplied from second pipe 7a and second pipe 2b to main pipe 70.

[0082] First pipe 6a supplies the refrigerant distributed by distributer 4 to heat exchanger 1a, and first pipe 6b supplies the refrigerant distributed by distributer 4 to heat exchanger 1b.

[0083] Heat exchanger 1a includes first header flow channel 28a and second header flow channel 29a, and heat exchanger 1b includes first header flow channel 28a and second header flow channel 29b.

[0084] First pipe 6a is connected to first header flow channel 28a, first pipe 6b is connected to first header flow channel 28b, second pipe 7a is connected to second header flow channel 29a, and second pipe 7b is connected to second header flow channel 29b.

[0085] First flow rate adjuster 81 is disposed on at least one of first pipe 6a and first pipe 6b, and second flow rate adjuster 82 is disposed on at least one of second pipe 7a and second pipe 7b.

[0086] Each of first flow rate adjuster 81 and second flow rate adjuster 82 adjusts the flow rate of the refrigerant flowing through the pipe.

[0087] Accordingly, if first flow rate adjuster 81 and second flow rate adjuster 82 are adjusted so that the pressure losses on the inlet sides and the pressure losses on the outlet sides of respective heat exchangers 1a and 1b become equal, the refrigerant can be distributed to respective heat exchangers 1a, 1b with the degree of dryness and the amount of circulation of the refrigerant being equalized. Therefore, the degree of equalization of the distributed refrigerant between heat exchangers 1a, 1b can be increased. Accordingly, it is possible to improve the heat exchange performance of entire heat exchanger unit 100 by further ensuring equal distribution of the refrigerant to respective heat exchangers 1a, 1b and equalizing the heat exchange efficiency.

(Second exemplary embodiment)

[0088] FIG. 7 is a diagram showing a schematic configuration of a heat exchanger unit according to a second exemplary embodiment of the present disclosure. FIG. 8 is a diagram showing a schematic configuration of a portion indicated by "a" in FIG. 7.

[0089] As shown in FIG. 7, heat exchanger unit 110 of the present exemplary embodiment has a branch pipe 9 provided at an upstream portion of inlet pipes 2a and 2b of heat exchangers 1a and 1b, and has a configuration of distributing the refrigerant, flowing into heat exchanger unit 110, to heat exchangers 1a, 1b. Also, a throttle pipe 10 is provided on the inlet side (upstream side) of branch pipe 9.

[0090] Other configurations and the configurations of heat exchangers 1a and 1b themselves are similar to those of the first exemplary embodiment, and the same parts are denoted by the same reference numerals and description thereof is omitted.

[0091] As shown in FIG. 7, branch pipe 9 is provided to a distribution part for distributing the refrigerant to respective first pipes 6a, 6b of a plurality of heat exchangers 1a, 1b. In the present exemplary embodiment, a Y branch pipe that branches into two is used as branch pipe 9. As shown in FIG. 8, on the inlet side (upstream side) of branch pipe 9, throttle pipe 10 having a smaller pipe diameter than a pipe diameter of inlet pipe 9a at the inlet port of branch pipe 9 is provided.

[0092] In the present exemplary embodiment, the refrigerant flowing from inlet pipe 9a of branch pipe 9 is throttled by throttle pipe 10 located upstream thereof, the flow velocity is increased, and the refrigerant forms an annular flow. Therefore, in branch pipe 9 (Y branch pipe), the refrigerant can be evenly distributed. Therefore, refrigerant having substantially the same gas-liquid balance can be supplied to heat exchangers 1a, 1b. Accordingly, the heat exchange efficiency of heat exchangers 1a, 1b can be made substantially uniform, and the heat exchange efficiency of heat exchanger unit 110 as a whole can be made good.

[0093] Further, as in the present exemplary embodiment, branch pipe 9 is a Y-branch pipe, so that even when branch pipe 9 is installed in a slightly inclined state, the refrigerant is hardly affected by gravity when being distributed. Therefore, the refrigerant can be supplied to heat exchangers 1a, 1b without collapse of a gas-liquid separation ratio of the refrigerant that has been throttled by throttle pipe 10 and distributed by branch pipe 9. Thus, the heat exchange efficiency of each of heat exchangers 1a, 1b can be more reliably improved, and the heat exchange efficiency of heat exchanger unit 110 as a whole can be improved.

[0094] Note that, instead of the above-described combination of branch pipe (Y-branch pipe) 9 and throttle pipe 10, a distributor may be provided upstream of first pipes 6a, 6b. With the distributor being provided, the refrigerant can be distributed substantially evenly to each of a plurality of heat exchangers 1a, 1b connected in parallel. Therefore, the heat exchange efficiency of heat exchanger unit 110 as a whole can be improved.

(Third exemplary embodiment)

[3-1. Configuration]

[0095] FIG. 9 is a refrigeration cycle diagram of an air conditioner according to a present third exemplary embodiment.

[0096] Air conditioner 200 of the present exemplary embodiment is configured by using any one of the heat exchanger units shown in the first and second exemplary embodiments.

[0097] As shown in FIG. 9, air conditioner 200 includes outdoor unit 51 and indoor unit 52 connected to outdoor unit 51.

[0098] Outdoor unit 51 is provided with compressor 53 that compresses refrigerant, four-way valve 54 that switches a refrigerant circuit depending on a cooling operation and a heating operation, outdoor heat exchanger 55 that performs heat exchange between the refrigerant and external air, decompressor 56 that decompresses the refrigerant, and outdoor air blower 59.

[0099] Indoor unit 52 is provided with indoor heat exchanger 57 that performs heat exchange between the refrigerant and indoor air, and indoor air blower 58.

[0100] Compressor 53, four-way valve 54, indoor heat exchanger 57, decompressor 56, and outdoor heat exchanger 55 are connected to form a refrigerant circuit through which the refrigerant flows, thereby forming a heat pump refrigeration cycle.

[0101] FIG. 10 is a diagram showing a cross-sectional configuration of the indoor unit of the air conditioner according to the third exemplary embodiment when viewed from the right side. FIG. 11 is a diagram showing a cross-sectional configuration of the indoor unit according to the third exemplary embodiment when viewed from above.

[0102] As shown in FIG. 10, indoor heat exchanger 57 includes housing 64, heat exchanger unit 60 disposed in housing 64, and heat exchange air blowing passage (air passage) 62 configured in housing 64. As heat exchanger unit 60, any of heat exchanger units 100, 110 shown in the first and second exemplary embodiments is used. Air outlet 61 is disposed at an outlet port of air passage 62. Further, suction port 63 is disposed at an inlet port of the air passage.

[0103] As shown in FIGS. 10 and 11, indoor heat exchanger 57 constituting heat exchanger unit 60 is disposed in air passage 62. Further, as shown in FIG. 11, indoor heat exchanger 57 is configured such that heat exchangers 1a, 1b are arranged side by side in a first direction crossing air passage 62. In the present exemplary embodiment, indoor heat exchanger 57 is arranged to fill the width of air passage 62. Specifically, heat exchangers 1a, 1b are arranged side by side in the left-right direction in FIG. 11 so as to face one air outlet 61 in plan view of the indoor unit 52.

[0104] In the refrigerant circuit of the present exemplary embodiment, as refrigerant, tetrafluoropropene or trifluoropropene, and difluoromethane, pentafluoroethane, or tetrafluoroethane can be used alone or as a mixture of two or three components, respectively.

[3-2. Operation]

[0105] Air conditioner 200 configured as described above switches operation between a cooling operation and a heating operation by switching the four-way valve.

[0106] During the cooling operation, four-way valve 54 is switched so that the discharge side of compressor 53 and outdoor heat exchanger 55 communicate with each other. Thus, the refrigerant compressed by compressor 53 becomes high-temperature and high-pressure refrigerant and is sent to outdoor heat exchanger 55 through four-way valve 54. Then, the refrigerant exchanges heat with the external air to release heat and is condensed to become high-pressure liquid refrigerant, which is sent to decompressor 56. The refrigerant is decompressed by decompressor 56 to become low-temperature and low-pressure two-phase refrigerant, which is sent to indoor unit 52. In indoor unit 52, the refrigerant flows into indoor heat exchanger 57. Then, the refrigerant exchanges heat with indoor air, thereby absorbing heat and evaporating to be low-temperature gas refrigerant. At this time, the room air is cooled through each exchange with the refrigerant to cool the room. Then, the refrigerant flowing out of indoor heat exchanger 57 returns to outdoor unit 51, and returns to compressor 53 via four-way valve 54.

[0107] On the other hand, during the heating operation, four-way valve 54 is switched so that the discharge side of compressor 53 and indoor unit 52 communicate with each other. Thus, the refrigerant compressed by compressor 53 becomes high-temperature and high-pressure refrigerant, passes through four-way valve 54, and is sent to indoor unit 52. The high-temperature and high-pressure refrigerant enters indoor heat exchanger 57, radiates heat by exchanging heat with indoor air, and is cooled. Thereby, the refrigerant is condensed and becomes high-pressure liquid refrigerant. At this time, the room air is heated through heat exchange with the refrigerant to heat the room. Thereafter, the refrigerant is sent to decompressor 56, and is decompressed in decompressor 56 to become low-temperature and low-pressure two-phase refrigerant, which is sent to outdoor heat exchanger 55. In outdoor heat exchanger 55, the refrigerant exchanges heat with the external air and evaporates, and returns to compressor 53 via four-way valve 54.

[0108] In air conditioner 200 of the present exemplary embodiment, in heat exchanger unit 60 constituting the indoor unit, the heat exchange efficiencies of heat exchangers 1a, 1b are equalized without variation. Therefore, the temperature of cool air or hot air blown out of air outlet 61 can be made substantially uniform in the width direction of the air outlet. For this reason, even when the fin-stacked heat exchangers are used as heat exchangers 1a, 1b, the temperature unevenness of the blown air is reduced, and highly reliable and high quality air conditioner 200 can be obtained.

[0109] Further, by using the fin-stacked heat exchangers as heat exchangers 1a, 1b, it is possible to reduce the diameter of refrigerant flow channel 31 and increase the number of paths of refrigerant flow channel 31. Thereby, the heat exchange efficiency of heat exchangers 1a, 1b can be increased, and high-performance air conditioner 200 with high energy saving can be obtained.

[0110] Note that, in the present exemplary embodiment, an example has been shown in which any one of heat exchanger units 100, 110 shown in the first and second exemplary embodiments is used for indoor unit 52. However, a configuration in which such a heat exchanger unit is used for at least one of outdoor unit 51 and indoor unit 52 is also acceptable. Thereby, the heat exchange efficiency can be improved in at least one of outdoor heat exchanger 55 and indoor heat exchanger 57, and the energy saving performance of air conditioner 200 can be improved.

(Fourth exemplary embodiment)

[0111] FIG. 12 is a diagram showing an arrangement configuration of a heat exchanger of an air conditioner according to the third exemplary embodiment.

[0112] In the present exemplary embodiment, details of arrangement of first pipe 6 and second pipe 7 of a plurality of heat exchangers 1a, 1b in indoor unit 52 of air conditioner 200 will be described.

[0113] As an example, description will be given on a case where, in air conditioner 200 described in the third exemplary embodiment, a plurality of heat exchangers 1a, 1b are arranged in an inclined state in housing 64 of indoor unit 52 as shown in FIG. 10. In one heat exchanger 1 of heat exchangers 1a, 1b, inlet pipe 2 (first pipe 6) connected to upstream header flow channel 28 and outlet pipe 3 (second pipe 7) connected to downstream header flow channel 29 are disposed as shown in FIG. 12. That is, first pipe 6 and second pipe 7 of one heat exchanger 1 of heat exchangers 1 (1a, 1b) are disposed in projection range W where header region H in which upstream header flow channel 28 and downstream header flow channel 29 of heat exchanger 1 are disposed is projected to a plane perpendicular to a direction substantially parallel to air flow B (see FIGS. 10 and 12).

[0114] Note that first pipe 6 and second pipe 7 of one heat exchanger 1 of heat exchangers 1 (1a, 1b) may be disposed in projection range W where header region H in which upstream header flow channel 28 and downstream header flow channel 29 of heat exchanger 1 are disposed is projected to a plane that is vertical and is parallel to the first direction.

[0115] For example, with respect to heat exchangers 1a, 1b arranged side by side along the first direction (the left-right direction in FIG. 11), in a case where a distribution part (distributer 4 or branch pipe 9) that distributes the refrigerant to first pipe 6a and first pipe 6b and a merging part (merging unit 5) that merges refrigerant from second pipe 7a and refrigerant from second pipe 7b are provided on one of the left and right sides, first pipe 6 and second pipe 7 of heat exchanger 1, located on the opposite side away from the side where the distribution part and the merging part are provided, extend along the direction in which heat exchangers 1a and 1b are arranged side by side (first direction). Therefore, first pipe 6 and second pipe 7 are arranged in above-described projection range W of header region H in which at least one of upstream header flow channel 28 and downstream header flow channel 29 is provided.

[0116] First pipe 6 and second pipe 7 of heat exchanger 1, of heat exchangers 1a, 1b arranged side by side along the first direction so as to cross air passage 62, located on the opposite side away from the side where a distribution part (distributer 4 or branch pipe 9) that distributes the refrigerant to first pipe 6a and first pipe 6b and a merging part (merging unit 5) that merges the refrigerant from second pipe 7a and the refrigerant from second pipe 7b are provided, cross air passage 62. However, with the above-described configuration, first pipe 6 and second pipe 7 are positioned in a downstream range of header region H (behind header region H) where upstream header flow channel 28 and downstream header flow channel 29 are provided and that is not subjected to heat exchange, of heat exchangers 1a, 1b. Accordingly, it is possible to minimize a decrease in the heat exchange efficiency caused by first pipe 6 and second pipe 7 crossing air passage 62 (airflow obstruction).

[0117] Therefore, the high heat exchange efficiency of heat exchangers 1a, 1b can be utilized to obtain high-performance air conditioner 200 with high energy saving.

[0118] Furthermore, first pipe 6 and second pipe 7 that cross air passage 62 only need to be piped within projection range W of header region H, and the diameters of first pipe 6 and second pipe 7 can be increased to projection surface range W of header area H. Therefore, when heat exchanger 1 is used as a condenser, first pipe 6 and second pipe 7 can function as a liquid pool for the refrigerant.

[0119] Note that, in the present exemplary embodiment, the arrangement positions of first pipe 6 and the second pipe 7 are within projection surface range W of header region H in which both upstream header flow channel 28 and downstream header flow channel 29 are provided. However, when upstream header flow channel 28 and downstream header flow channel 29 are provided separately at both ends of plate fin 21, the arrangement positions of first pipe 6 and the second pipe 7 may be within projection surface range W of header region H where either one is provided.

[0120] As described above, the heat exchanger unit according to the present disclosure and the air conditioner using the same have been described using the above exemplary embodiments. However, the present disclosure is not limited thereto. That is, it should be construed that the exemplary embodiments disclosed herein are illustrative in all aspects, and are not restrictive. The scope of the present disclosure is represented by the scope of the claims and not by the above description, and it is intended that all modifications within the sense and scope equivalent to the claims are involved in the scope of the present disclosure.

INDUSTRIAL APPLICABILITY

[0121] The present disclosure is directed to a heat exchanger unit that equalizes heat exchange efficiency of respective heat exchangers connected in parallel and exhibits good heat exchange performance, and a high performance and high energy-saving air conditioner using the heat exchanger unit. Therefore, the present invention can be applied to various heat exchangers and air conditioners such as an air conditioning apparatus for home and commercial use.

REFERENCE MARKS IN THE DRAWINGS

[0122] 

1, 1a, 1b heat exchanger

2, 2a, 2b inlet pipe (first pipe)

3, 3a, 3b outlet pipe (second pipe)

4 distributer (distribution part)

5 merging unit (merging part)

6, 6a, 6b inflow pipe (first pipe)

7, 7a, 7b outflow pipe (second pipe)

81 flow rate adjuster (first flow rate adjuster)

82 flow rate adjuster (second flow rate adjuster)

9 branch pipe

9a inlet pipe

10 throttle pipe

21 plate fin

22, 22a, 22b plate fin stacked body

23, 23a, 23b end plate

24, 24a, 24b end plate

25 connection means

26a first plate member

26b second plate member

27 protrusion

28, 28a, 28b upstream header flow channel (first header flow channel)

29, 29a, 29b downstream header flow channel (second header flow channel)

31 refrigerant flow channel

31a upstream header flow channel-side refrigerant flow channel (first refrigerant flow channel)

31b downstream header flow channel-side refrigerant flow channel (second refrigerant flow channel)

34a, 34b passage

35 slit groove

36 non-porous portion

36a wall

51 outdoor unit

52 indoor unit

53 compressor

54 four-way valve

55 outdoor heat exchanger

56 decompressor

57 indoor heat exchanger

58 indoor air blower

59 outdoor air blower

60 heat exchanger unit

61 air outlet

62 air passage for heat exchange (air passage)

63 suction port

64 housing

70 main pipe

100, 110 heat exchanger unit

200 air conditioner

Claims

1. A heat exchanger unit comprising a plurality of heat exchangers, each of the plurality of the heat exchangers including:

a first pipe into which refrigerant flows;

a first header flow channel that communicates with an outflow side of the first pipe;

a second header flow channel disposed downstream of the first header flow channel;

a plurality of refrigerant flow channels that allow the first header flow channel and the second header flow channel to communicate with each other; and

a second pipe that communicates with an outflow side of the second header flow channel,

the heat exchanger unit further comprising:

a distribution part that distributes the refrigerant to the first pipe in each of the plurality of the heat exchangers;

a merging part that merges the refrigerant from the second pipe in each of the plurality of the heat exchangers;

a first flow rate adjuster provided to the first pipe in at least one of the plurality of the heat exchangers; and

a second flow rate adjuster provided to the second pipe in at least one of the plurality of the heat exchangers.

2. The heat exchanger unit according to claim 1, wherein
each of the plurality of the heat exchangers is a plate fin stacked-type heat exchanger having a plurality of plate fins,
each of the plurality of the plate fins includes two plate members stacked, and the plurality of the refrigerant flow channels are formed of a dented groove formed on at least one of the two plate members, and
each of the plurality of the plate fins has a header region in which at least one of the first header flow channel and the second header flow channel is disposed.

3. The heat exchanger unit according to claim 1 or 2, wherein a distributor is provided to the merging part.

4. The heat exchanger unit according to claim 1 or 2, wherein
a branch pipe is provided to the merging part, and
a throttle pipe having a pipe diameter that is smaller than a pipe diameter at an inlet port of the branch pipe is provided upstream of the branch pipe.

5. An air conditioner comprising:

an indoor unit; and

an outdoor unit,

wherein at least one of the indoor unit and the outdoor unit includes the heat exchanger unit according to any one of claims 1 to 4.

6. The air conditioner according to claim 5, wherein
the indoor unit includes:

a housing;

the heat exchanger unit disposed in the housing;

an air passage configured in the housing; and

an air outlet disposed at an outlet port of the air passage, and

the plurality of the heat exchangers of the heat exchanger unit are arranged side by side in the air passage along a first direction crossing the air passage.

7. The air conditioner according to claim 6, wherein
the distribution part and the merging part are disposed outside one end, in the first direction, of the plurality of the heat exchangers arranged side by side, and
in each of the plurality of the heat exchangers, the first pipe and the second pipe are disposed in a projection range of the header region projected to a plane perpendicular to a direction of air flowing through the air passage, or a plane which is vertical and is parallel to the first direction.

Drawing