Heat exchanger unit, air conditioning indoor machine, and refrigeration cycle device

Abstract

To improve flow dividing performance of a heat exchanger unit comprising a flow dividing passage.SOLUTION: A flow dividing passage (70) includes: a first inflow passage (71) and a second inflow passage (72) extending in a second direction along a vertical direction; a flow dividing space (80) to which a first outflow port (O1) of the first inflow passage (71) and a second outflow port (O2) of the second inflow passage (72) are connected; and a plurality of three or more outflow passages (91, 92, and 93) comprising inflow ports (I1, I2, and I3) connected to the flow dividing space (80) respectively, and extending in the second direction.SELECTED DRAWING: Figure 8

Description

[Technical field]

[0001] The present disclosure relates to a heat exchanger unit, an air conditioning indoor unit, and a refrigeration cycle apparatus. [Background technology]

[0002] Patent Document 1 discloses a header provided in a heat exchanger. The header in Patent Document 1 is constructed by stacking multiple plates. As shown in FIG. 6 of Patent Document 1, a space (division space) for dividing the flow of refrigerant is formed inside the header. One inflow path and multiple outflow paths are connected to the division space. The refrigerant that flows from the inflow path into the division space is divided into multiple outflow paths. The refrigerant divided into each outflow path is supplied to each heat transfer tube of the heat exchanger. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent Publication No. 2021-179308 Summary of the Invention [Problem to be solved by the invention]

[0004] In a flow dividing structure as described in Patent Document 1, if the refrigerant is biased toward some of the outflow paths, the performance of the heat exchanger will be reduced.

[0005] An object of the present disclosure is to improve the flow splitting performance of a heat exchanger unit having a flow splitting passage. [Means for solving the problem]

[0006] The first aspect is directed to a heat exchanger unit, and includes a heat exchange section (40A) having fins (41) and heat transfer tubes (42), and a plate stack (50, 60) having a plurality of plates (P) stacked in a first direction along the horizontal direction and having a refrigerant flow path (51) communicating with the heat transfer tubes (42). The plate stack (50, 60) is formed with a diversion flow path (70) for diversion of the refrigerant. The diversion flow path (70) includes a first inlet passage (71) and a second inlet passage (72) extending in a second direction along the vertical direction, a diversion space (80) connecting a first outlet (O1) of the first inlet passage (71) and a second outlet (O2) of the second inlet passage (72), and three or more outlet paths (91, 92, 93) each having an inlet (I1, I2, I3) connected to the diversion space (80) and extending in the second direction.

[0007] In the first aspect, the first inlet channel (71) and the second inlet channel (72) are connected to the flow division space (80). By providing a plurality of inlet channels (71, 72), the lengths of the paths through which the refrigerant flowing into the flow division space (80) flows before flowing into each of the outlet channels (91, 92, 93) can be made close to each other. As a result, the flow resistances of these paths can be made close to each other, thereby improving the flow division performance.

[0008] In the second embodiment, in the first embodiment, the first outlet (O1) and the second outlet (O2) are disposed on the opposite side in the second direction to the multiple inlets (I1, I2, I3) across the flow division space (80).

[0009] In the second aspect, the flow resistance of the fluid flowing through the flow division space (80) can be reduced.

[0010] In the third embodiment, the first outlet (O1) and the multiple inlets (I1, I2, I3) are offset from each other when viewed from the second direction in the second embodiment. The second outlet (O2) and the multiple inlets (I1, I2, I3) are offset from each other when viewed from the second direction in the second embodiment.

[0011] In the third aspect, the first outlet (O1) and the inlets (I1, I2, I3) do not overlap when viewed in the second direction, and the second outlet (O2) and the inlets (I1, I2, I3) do not overlap when viewed in the second direction, so that it is possible to prevent the refrigerant from being biased toward some of the inlets (I1, I2, I3).The first outlet (O) and the inlets (I1, I2, I3) do not overlap when viewed in the second direction, so that it is possible to prevent the refrigerant from being biased toward some of the inlets (I1, I2, I3).

[0012] A fourth aspect is any one of the first to third aspects, wherein the multiple inlets (I1, I2, I3) are disposed between the first outlet (O1) and the second outlet (O2) when viewed from the second direction.

[0013] In the fourth aspect, the refrigerant flowing out from the first outlet (O1) and the second outlet (O2) flows so as to sandwich the inlets (I1, I2, I3), thereby preventing the refrigerant from being biased toward some of the inlets (I1, I2, I3).

[0014] In the fifth aspect, in any one of the first to fourth aspects, the plurality of plates (P) each include a plurality of flow dividing plates (FP2, FP3, FP4) adjacent to each other in the first direction, each of which has a plate space (81, 82, 83). The flow dividing space (80) is formed by the plate spaces (81, 82, 83) of the plurality of flow dividing plates (FP2, FP3, FP4) continuing in the first direction.

[0015] In the fifth aspect, the plurality of flow distribution plates (FP2, FP3, FP4) are stacked in the first direction, so that the plate spaces (81, 82, 83) of the respective flow distribution plates (FP2, FP3, FP4) are continuous in the first direction. As a result, in the heat exchanger unit, the plurality of plate spaces (81, 82, 83) form a flow distribution space (80). Since the flow distribution space (80) does not extend to one plate (P) but extends to a plurality of plates (P), the volume of the space expands in the first direction (stacking direction) of the plates (P). This makes it possible to prevent the distances between the first outlet (O1) or the second outlet (O2) and each of the inlets (I1, I2, I3) from differing greatly. As a result, it is possible to prevent the flow path resistance between the first outlet (O1) or the second outlet (O2) and each of the inlets (I1, I2, I3) from differing significantly, thereby preventing the refrigerant from flowing unevenly into some of the outlet paths (91, 92, 93).

[0016] In the sixth aspect, in the fifth aspect, the first outlet (O1) and the second outlet (O2) are formed in different flow dividing plates (FP2, FP4). Since the distance between the first outlet (O1) and the second outlet (O2) can be increased, it becomes easier to reduce the distance between the first outlet (O1) or the second outlet (O2) and the multiple inlets (I1, I2, I3).

[0017] In a seventh aspect, in the sixth aspect, the multiple flow distribution plates (FP2, FP3, FP4) include a first plate (FP2) in which a first outlet (O1) is formed, a second plate (FP4) in which a second outlet (O2) is formed, and a third plate (FP3) arranged between the first plate (FP2) and the second plate (FP2) and in which at least one of the multiple inlets (I1, I2, I3) is formed.

[0018] In the seventh aspect, the inlets (I1, I2, I3) of the third plate (FP3) are sandwiched between the first outlet (O1) and the second outlet (O2) in the stacking direction (first direction). The refrigerant flowing out of the first outlet (O1) and the second outlet (O2) flows so as to sandwich at least one of the inlets (I1, I2, I3) in the first direction, so that it is possible to suppress the refrigerant from being biased toward some of the inlets (I1, I2, I3).

[0019] An eighth aspect is the seventh aspect, wherein all of the plurality of inlets (I1, I2, I3) are formed in the third plate (FP3).

[0020] In the eighth aspect, the refrigerant flowing out from the first outlet (O1) and the second outlet (O2) flows so as to sandwich all of the inlets (I1, I2, I3) in the first direction, thereby preventing the refrigerant from being biased toward some of the inlets (I1, I2, I3).

[0021] In a ninth aspect, in the eighth aspect, the branch flow path (70) includes a branch path (76) that branches the refrigerant into the first inlet path (71) and the second inlet path (72). The branch path (76) is formed in the third plate (FP3).

[0022] In the ninth aspect, by forming a branch passage (76) in the third plate (FP3) between the first plate (FP2) and the second plate (FP4), it becomes easier to divert the refrigerant from the branch passage (76) to the first outlet (O1) of the first plate (FP2) and the second outlet (O2) of the second plate (FP4).

[0023] In a tenth aspect, in any one of the first to eighth aspects, the flow division space (80) has a horizontally elongated shape extending in a third direction perpendicular to the first direction and aligned horizontally. The first outlet (O1) is disposed near one end of the flow division space (80) in the third direction. The second outlet (O2) is disposed near the other end of the flow division space (80) in the third direction.

[0024] In the tenth aspect, the plurality of inlets (I1, I2, I3) are sandwiched between the first outlet (O1) and the second outlet (O2) in the third direction. The refrigerant flowing out from the first outlet (O1) and the second outlet (O2) flows so as to sandwich the inlets (I1, I2, I3) in the third direction, so that it is possible to suppress the refrigerant from being biased toward some of the inlets (I1, I2, I3).

[0025] In an eleventh embodiment, the number of the outlet channels (91, 92, 93) is five or less.

[0026] In the eleventh aspect, by limiting the number of the outflow channels (91, 92, 93) to five or less, it is possible to suppress deterioration in the flow division performance caused by increasing the number of the outflow channels (91, 92, 93).

[0027] A twelfth aspect is any one of the first to eleventh aspects, wherein the plate stack (50, 60) has a first region (A1) that does not overlap with the heat exchange section (40A).

[0028] In the twelfth aspect, interference between the heat transfer tube (42) of the heat exchange section (40A) and the branch flow path (70) in the first direction can be suppressed.

[0029] A thirteenth aspect is an air conditioning indoor unit equipped with a heat exchanger unit (U) according to any one of the first to twelfth aspects.

[0030] A fourteenth aspect is a refrigeration cycle apparatus including a refrigerant circuit (11) to which a heat exchanger unit (U) according to any one of the first to thirteenth aspects is connected. [Brief description of the drawings]

[0031] [Figure 1] FIG. 1 is a piping diagram of an air conditioner according to an embodiment. [Diagram 2] FIG. 2 is a front view of the air conditioning indoor unit. [Diagram 3] FIG. 3 is a cross-sectional view of the air conditioning indoor unit taken along line AA. [Figure 4]FIG. 4 is a front view showing the internal structure of the air conditioning indoor unit. [Diagram 5] FIG. 5 is a cross-sectional view showing a connection structure between a heat transfer tube and a plate stack. [Figure 6] FIG. 6 is a perspective view of a main part of the heat exchanger unit. [Figure 7] FIG. 7 is an exploded perspective view of the front plate assembly. [Figure 8] FIG. 8 is a perspective view of a main part of the flow division channel. [Figure 9] FIG. 9 is an enlarged side view of the flow dividing passage of the third front plate, and corresponds to the portion surrounded by the dashed line R9 in FIG. [Figure 10] FIG. 10 is an enlarged side view of the flow dividing passage of the second front plate, and corresponds to the portion surrounded by the dashed line R10 in FIG. [Figure 11] FIG. 11 is an enlarged side view of the flow dividing passage of the fourth front plate, and corresponds to the portion surrounded by the dashed line R11 in FIG. [Figure 12] FIG. 12 is a cross-sectional view of the shunt channel. [Figure 13] FIG. 13 is a cross-sectional view of the flow dividing channel of the first modified example. [Figure 14] FIG. 14 is a cross-sectional view of the flow dividing channel of the second modification. [Figure 15] FIG. 15 is a cross-sectional view of the flow dividing channel of the third modification. [Figure 16] FIG. 16 is a cross-sectional view of the flow dividing channel of the fourth modification. [Figure 17] FIG. 17 is a cross-sectional view of the flow dividing channel of the fifth modification. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0032] Hereinafter, the embodiments of the present disclosure will be described in detail with reference to the drawings. Note that the present disclosure is not limited to the embodiments shown below, and various modifications are possible within the scope of the technical idea of ​​the present disclosure. Since each drawing is intended to conceptually explain the present disclosure, dimensions, ratios, or numbers may be exaggerated or simplified as necessary for easy understanding.

[0033] (1) Overall configuration of air conditioning system This embodiment is an air conditioner (10) including a heat exchanger unit (U). The air conditioner (10) adjusts the temperature of air in an indoor space (5), which is a target space.

[0034] As shown in Fig. 1, the air conditioner (10) is an example of a refrigeration cycle device including a refrigerant circuit (11). The refrigerant circuit (11) is filled with a refrigerant. The refrigerant circuit (11) performs a refrigeration cycle by circulating the refrigerant.

[0035] The air conditioner (10) includes an outdoor unit (20), an indoor unit (30), a first connecting pipe (12), and a second connecting pipe (13). The air conditioner (10) is a pair type having one outdoor unit (20) and one indoor unit (30). The first connecting pipe (12) is a gas connecting pipe, and the second connecting pipe (13) is a liquid connecting pipe. In the air conditioner (10), a refrigerant circuit (11) is formed by connecting the outdoor unit (20) and the indoor unit (30) with the first connecting pipe (12) and the second connecting pipe (13).

[0036] The outdoor unit (20) is installed outdoors and includes an outdoor casing (20a), a compressor (21) housed in the outdoor casing (20a), an outdoor heat exchanger (22), an outdoor expansion valve (23), a four-way switching valve (24), and an outdoor fan (25).

[0037] The compressor (21) is a rotary compressor such as a swing piston type, rotary type, or scroll type. The outdoor heat exchanger (22) exchanges heat between the refrigerant and outdoor air. The outdoor heat exchanger (22) is a fin-and-tube air heat exchanger. The outdoor expansion valve (23) reduces the pressure of the refrigerant. The outdoor expansion valve (23) is an electronic expansion valve. The four-way switching valve (24) switches between a first state (a state shown by a solid line in FIG. 1) and a second state (a state shown by a dashed line in FIG. 1). In the first state, the four-way switching valve (24) communicates between the discharge portion of the compressor (21) and the gas end of the outdoor heat exchanger (22) and also communicates between the suction portion of the compressor (21) and the first connection pipe (12). The four-way switching valve (24) in the second state communicates the discharge portion of the compressor (21) with the first connection pipe (12) and also communicates the suction portion of the compressor (21) with the gas end of the outdoor heat exchanger (22). The outdoor fan (25) transports the air flowing through the outdoor heat exchanger (22). The outdoor fan (25) is a propeller fan.

[0038] The indoor unit (30) includes a casing (31), an indoor fan (32), and a heat exchanger unit (U). The indoor fan (32) and the heat exchanger unit (U) are housed in the casing (31).

[0039] (2) Indoor unit The indoor unit (30) which is an indoor air conditioner will be described in detail with reference to Figs. 2 to 4. The indoor unit (30) of this embodiment is a wall-mounted type provided on a wall of the indoor space (5). Note that the terms "upper", "lower", "right", "left", "front", and "rear" described below correspond to the directions of the arrows shown in Figs. 2 and 3 and indicate the directions when the casing (31) is viewed from the front side.

[0040] (2-1) Casing The casing (31) is formed in a horizontally elongated box shape and has a front plate (31a), a rear plate (31b), an upper plate (31c), a lower plate (31d), a first side plate (31e), and a second side plate (31f).

[0041] The front plate (31a) is formed on the front side of the casing (31) and constitutes the front surface of the casing (31). The rear plate (31b) is formed on the rear side of the casing (31) and constitutes the rear surface of the casing (31). The upper plate (31c) is formed on the upper side of the casing (31) and constitutes the upper surface of the casing (31). The lower plate (31d) is formed on the lower side of the casing (31) and constitutes the lower surface of the casing (31). The first side plate (31e) is formed on the right side of the casing (31) and constitutes the right surface of the casing (31). The second side plate (31f) is formed on the left side of the casing (31) and constitutes the left surface of the casing (31).

[0042] An intake port (33) is formed in the upper plate (31c), and an exhaust port (34) is formed in the lower plate (31d). An air passage (38) is formed inside the casing (31) from the intake port (33) to the exhaust port (34). The intake port (33) extends in the longitudinal direction (left-right direction) of the casing (31). The intake port (33) is an opening for taking air from the indoor space (5) into the air passage (38). An exhaust port (34) is formed in the lower plate (31d). The exhaust port (34) extends in the longitudinal direction of the casing (31). The exhaust port (34) is an opening for blowing air from the air passage (38) into the indoor space (5).

[0043] (2-2) Filter The indoor unit (30) includes a filter (35). The filter (35) is disposed on the rear side of the suction port (33) and upstream of the indoor heat exchanger (40). The filter (35) collects dust in the air sent from the suction port (33) to the indoor heat exchanger (40). The indoor unit (30) may include a dust removal mechanism that removes the dust collected by the filter (35).

[0044] (2-3) Heat exchange unit The heat exchanger unit (U) includes an indoor heat exchanger (40), an intermediate pipe (66), an indoor expansion valve (37), a liquid relay pipe (67), and a gas relay pipe (68). The indoor heat exchanger (40) includes a heat exchanger body (B) and two plate stacks (50, 60) connected to the heat exchanger body (B). These will be described in detail later.

[0045] (2-4) Indoor fan The indoor fan (32) is disposed in the air passage (38). The indoor fan (32) is disposed in the air passage (38) downstream of the indoor heat exchanger (40). The indoor fan (32) is a crossflow fan. The indoor fan (32) has a fan rotor that extends in the longitudinal direction of the casing (31).

[0046] (2-5) Flap The indoor unit (30) has a flap (36) that adjusts the direction of air blown out of the air outlet (34). The flap (36) adjusts the air direction in the vertical direction. The indoor unit (30) may have a plurality of flaps (36). The flap (36) may adjust the air direction in the horizontal direction.

[0047] (3) Details of indoor heat exchanger The indoor heat exchanger (40) will be described in detail with reference to Figs. 3 to 9. The indoor heat exchanger (40) exchanges heat between air and a refrigerant. The indoor heat exchanger (40) is a fin-and-tube air heat exchanger. The indoor heat exchanger (40) includes a heat exchanger body (B) and two plate stacks (50) connected to the heat exchanger body (B).

[0048] (3-1) Heat exchanger body 4 and 5, the heat exchanger body (B) has a plurality of fins (41) arranged in the longitudinal direction of the casing (31) and a plurality of heat transfer tubes (42) extending in the arrangement direction of the fins (41). The plate stacks (50, 60) have therein refrigerant flow paths (51, 61) that communicate with the heat transfer tubes (42).

[0049] The arrangement direction of the fins (41) corresponds to the longitudinal direction (here, the left-right direction) of the casing (31). The fins (41) are rectangular plate-shaped having long sides and short sides. The thickness direction of the fins (41) corresponds to the arrangement direction of the fins (41). The multiple fins (41) are arranged at predetermined intervals in the thickness direction. This interval defines an air flow path. The material of the fins (41) is an aluminum alloy.

[0050] The heat transfer tubes (42) are made of an aluminum alloy. A refrigerant flow path is formed inside the heat transfer tubes (42). The heat transfer tubes (42) extend parallel to one another and penetrate the fins (41). One end of the heat transfer tubes (42), which is a right end, protrudes to the right of the fins (41). One end of the heat transfer tubes (42) is connected to the plate stack (50, 60). Of the other ends of the heat transfer tubes (42), which are left ends, the left ends of two adjacent heat transfer tubes (42) are connected to each other by a U-shaped tube (49). The two adjacent heat transfer tubes (42) and the U-shaped tube (49) connecting them are formed integrally and seamlessly.

[0051] The indoor heat exchanger (40) of this embodiment has a front heat exchange section (40A) which is a first heat exchange section, and a rear heat exchange section (40B) which is a second heat exchange section. The front heat exchange section (40A) is located toward the front side of the casing (31), and the rear heat exchange section (40B) is located toward the rear side of the casing (31). The front heat exchange section (40A) and the rear heat exchange section (40B) are arranged in the front-to-rear direction on both sides of the indoor fan (32). The front-to-rear direction is a direction perpendicular to the axial direction and the up-down direction of the heat transfer tube (42).

[0052] The front heat exchange section (40A) includes a front main heat exchange section (43), a first auxiliary heat exchange section (44), and a second auxiliary heat exchange section (45).

[0053] The front main heat exchange section (43) is disposed closer to the indoor fan (32) in the front heat exchange section (40A). The front main heat exchange section (43) has an outer shape formed in a V-shape when viewed in the axial direction of the heat transfer tubes (42). The tip of the V-shape faces forward. The fins (41) constituting the front main heat exchange section (43) have a first portion (41a) extending obliquely upward toward the rear side, and a second portion (41b) extending obliquely downward toward the rear side. The angle between the extending direction of the first portion (41a) and the extending direction of the second portion (41b) is approximately 90° to 110°. The first portion (41a) and the second portion (41b) may be integrally formed or may be separate.

[0054] The first auxiliary heat exchange section (44) is provided on the inlet side (front side) of the first front main heat exchange section (43a). The lengths of the long sides and the short sides of the fins (41) of the first auxiliary heat exchange section (44) are shorter than those of the fins (41) of the first front main heat exchange section (43a). The number of heat transfer tubes (42) in the direction along the long sides (hereinafter referred to as the number of stages) of the first auxiliary heat exchange section (44) is smaller than the number of stages of the heat transfer tubes (42) of the first front main heat exchange section (43a). The number of heat transfer tubes (42) in the direction along the short sides (hereinafter referred to as the number of rows) of the first auxiliary heat exchange section (44) is smaller than the number of rows of the heat transfer tubes (42) of the first front main heat exchange section (43a).

[0055] The second auxiliary heat exchange section (45) is provided on the inlet side (front side) of the second front main heat exchange section (43b). The lengths of the long sides and the short sides of the fins (41) of the second auxiliary heat exchange section (45) are shorter than those of the fins (41) of the second front main heat exchange section (43b). The number of stages and rows of the heat transfer tubes (42) of the second auxiliary heat exchange section (45) is smaller than the number of stages and rows of the heat transfer tubes (42) of the second front main heat exchange section (43b).

[0056] The rear heat exchange section (40B) has a rear main heat exchange section (46) and a third auxiliary heat exchange section (47). The rear main heat exchange section (46) is disposed closer to the indoor fan (32) in the rear heat exchange section (40B). The third auxiliary heat exchange section (47) is provided on the inlet side (rear side) of the rear main heat exchange section (46). The lengths of the long and short sides of the fins (41) of the third auxiliary heat exchange section (47) are shorter than the lengths of the long and short sides of the fins (41) of the rear main heat exchange section (46). The number of stages and rows of the heat transfer tubes (42) of the third auxiliary heat exchange section (47) is smaller than the number of stages and rows of the heat transfer tubes (42) of the rear main heat exchange section (46).

[0057] As shown in Fig. 5, one end of the heat transfer tube (42) has a flare portion (48) that is flared. The flare portion (48) has an expanded diameter portion (48a) whose diameter increases as it approaches the plate stack (50, 60), and a cylindrical portion (48b) that extends in the axial direction with the same diameter as the expanded diameter portion (48a) from the end of the plate stack (50, 60) side. As will be described in detail later, the flare portion (48) is a portion that is connected to a heat transfer tube side connection portion (53, 63) of the plate stack (50, 60).

[0058] (3-2) Plate stack The plate stack (50, 60) is disposed to the right of the rightmost fin (41) and in parallel with the fin (41). The plate stack (50, 60) is connected to one end of the heat transfer tube (42). As shown in FIG. 6, the plate stack (50, 60) includes a front plate stack (50) connected to the heat transfer tube (42) of the front heat exchange section (40A) and a rear plate stack (60) connected to the heat transfer tube (42) of the rear heat exchange section (40B). The front plate stack (50) is disposed so as to overlap the front heat exchange section (40A) in the axial direction of the heat transfer tube (42). The rear plate stack (60) is disposed so as to overlap the rear heat exchange section (40B) in the axial direction of the heat transfer tube (42).

[0059] (3-2-1) Front plate assembly The front plate stack (50) has a front main body portion (52) having a refrigerant flow path therein (strictly speaking, a first refrigerant flow path (51)), and a plurality of front connection portions (53) connecting the plurality of heat transfer tubes (42) of the front heat exchange section (40A) to the first refrigerant flow path (51).

[0060] 5 to 7, the front main body portion (52) is a thick plate-like member formed by stacking five front plates. The stacking direction of the front plates is the same as the axial direction of the heat transfer tubes (42).

[0061] In the front plate stack (50), a first front plate (FP1), a second front plate (FP2), a third front plate (FP3), a fourth front plate (FP4), and a fifth front plate (FP5) are stacked in order from the side closest to the front heat exchange section (40A). The first front plate (FP1) is a cover plate on the heat exchanger body (B) side in the axial direction of the heat transfer tubes (42). The fifth front plate (FP5) is a cover plate on the opposite side to the heat exchanger body (B) in the axial direction of the heat transfer tubes (42) (the first side plate (31e) side of the casing (31)). The second front plate (FP2), the third front plate (FP3), and the fourth front plate (FP4) are intermediate plates sandwiched between the first front plate (FP1) and the fifth front plate (FP5). The five front plates are flat members having the same outer edge shape. Each front plate is made of the same material as the heat transfer tube (42) and the front connection part (53). In this embodiment, each front plate is made of an aluminum alloy. The first front plate (FP1) and the fifth front plate (FP5) have a thickness of 1.5 mm. The second front plate (FP2), the third front plate (FP3), and the fourth front plate (FP4) have a thickness of 3.0 mm. The front plates are joined to each other by furnace brazing. Note that the number of front plates is an example, and the number of front plates may be four or less, or six or more. Hereinafter, when there is no need to distinguish between the front plates, they are simply referred to as front plates.

[0062] (3-2-2) Rear plate assembly The rear plate stack (60) has a rear main body portion (62) having a refrigerant flow path (more precisely, a second refrigerant flow path (61)) therein, and a plurality of rear connection portions (63) that connect the plurality of heat transfer tubes (42) of the rear heat exchange portion (40B) to the second refrigerant flow path (61).

[0063] 5 and 6, the rear body portion (62) is a thick plate-like member formed by stacking five rear plates. The stacking direction of the rear plates is the same as the axial direction of the heat transfer tubes (42).

[0064] In the rear plate stack (60), a first rear plate (BP1), a second rear plate (BP2), a third rear plate (BP3), a fourth rear plate (BP4), and a fifth rear plate (BP5) are stacked in order from the side closest to the rear heat exchange section (40B). The first rear plate (BP1) is a cover plate on the heat exchanger body (B) side in the axial direction of the heat transfer tubes (42). The fifth rear plate (BP5) is a cover plate on the opposite side to the heat exchanger body (B) in the axial direction of the heat transfer tubes (42) (the side of the first side plate (31e) of the casing (31)). The second rear plate (BP2), the third rear plate (BP3), and the fourth rear plate (BP4) are intermediate plates sandwiched between the first rear plate (BP1) and the fifth rear plate (BP5). The five rear plates are flat members having the same outer edge shape. Each rear plate is made of the same material as the heat transfer tube (42) and the rear connection part (63). In this embodiment, each rear plate is made of an aluminum alloy. The first rear plate (BP1) and the fifth rear plate (BP5) have a thickness of 1.5 mm. The second rear plate (BP2), the third rear plate (BP3), and the fourth rear plate (BP4) have a thickness of 3.0 mm. The rear plates are joined to each other by furnace brazing. Note that the number of rear plates is an example, and the number of rear plates may be four or less, or six or more. Hereinafter, when it is not necessary to distinguish between the rear plates, they will simply be referred to as rear plates. Furthermore, the front plates and the rear plates will also be collectively referred to as plates (P).

[0065] (3-2-3) Heat transfer tube side connection 5, the plate stack (50, 60) has a plurality of front connection portions (53) and a plurality of rear connection portions (63). The plurality of front connection portions (53) are provided on the front plate stack (50), and the plurality of rear connection portions (63) are provided on the rear plate stack (60). When there is no need to distinguish between the front connection portions (53) and the rear connection portions (63), they are also referred to as heat transfer tube side connection portions (53, 63).

[0066] The front connection portion (53) is provided on the heat exchanger body (B) side of the first front plate (FP1) of the front main body portion (52). The front connection portion (53) protrudes from the front main body portion (52) toward the front heat exchange portion (40A) in the axial direction of the heat transfer tube (42).

[0067] The rear connection portion (63) is provided on the heat exchanger body (B) side of the first rear plate (BP1) of the rear main body portion (62). The rear connection portion (63) protrudes from the rear main body portion (62) toward the rear heat exchange portion (40B) in the axial direction of the heat transfer tube (42).

[0068] The heat transfer tube side connection parts (53, 63) are circular tubes. The material of the heat transfer tube side connection parts (53, 63) is an aluminum alloy. As shown in FIG. 5 , the tip parts of the heat transfer tube side connection parts (53, 63) are inserted into the ends of the corresponding heat transfer tubes (42). In other words, the ends of the heat transfer tubes (42) are inserted outside the heat transfer tube side connection parts (53, 63). The heat transfer tube side connection parts (53, 63) are inserted into the flare parts (48) of the corresponding heat transfer tubes (42). The heat transfer tube side connection parts (53, 63) are inserted into the flare parts (48) and joined to the cylindrical parts (48b) of the flare parts (48) by burner brazing.

[0069] (3-3) Intermediate piping 6, the heat exchanger unit (U) has an intermediate pipe (66). The intermediate pipe (66) connects the front heat exchange section (40A) and the rear heat exchange section (40B). In this embodiment, the intermediate pipe (66) is connected to an indoor expansion valve (37).

[0070] One end of the intermediate pipe (66) is connected to the front plate stack (50). Specifically, one end of the intermediate pipe (66) is connected to a surface of the front main body portion (52) opposite the front heat exchange portion (40A). One end of the intermediate pipe (66) is connected to the first refrigerant flow path (51). The other end of the intermediate pipe (66) is connected to the rear plate stack (60). Specifically, the other end of the intermediate pipe (66) is connected to a surface of the rear main body portion (62) opposite the rear heat exchange portion (40B). The other end of the intermediate pipe (66) is connected to the second refrigerant flow path (61).

[0071] (3-4) Indoor expansion valve The indoor expansion valve (37) is disposed on the right side of the heat exchanger body (B). The indoor expansion valve (37) is connected to the intermediate pipe (66). The indoor expansion valve (37) reduces the pressure of the refrigerant flowing through the intermediate pipe (66). The indoor expansion valve (37) is an electronic expansion valve.

[0072] (3-5) Liquid relay pipe 6, the heat exchanger unit (U) has a liquid relay pipe (67). One end of the liquid relay pipe (67) is connected to the front plate stack (50). The other end of the liquid relay pipe (67) is connected to the second connection pipe (13), which is a liquid connection pipe, outside the casing (31).

[0073] (3-6) Gas relay pipe 6, the heat exchanger unit (U) has a gas relay pipe (68). One end of the gas relay pipe (68) is connected to the rear plate assembly (60). The other end of the gas relay pipe (68) is connected to the first connection pipe (12), which is a gas connection pipe, outside the casing (31).

[0074] (4) Diversion channel A diversion flow path (70) is formed in the front plate stack (50). The diversion flow path (70) is a part of the first refrigerant flow path (51). The diversion flow path (70) diverts the refrigerant inside the front plate stack (50). The diversion flow path (70) will be described in detail with reference to FIGS. 6 to 12. In the following description, the first direction corresponds to the stacking direction of the plates (P) (the left-right direction in FIG. 6), the second direction corresponds to the direction along the vertical direction (the up-down direction in FIG. 6), and the third direction corresponds to the direction perpendicular to the first direction and along the horizontal direction (the front-rear direction in FIG. 6).

[0075] (4-1) Basic configuration of the distribution channel The flow-division passage (70) is formed by stacking a plurality of plates (P). The flow-division passage (70) is located in a first region (A1) of the front plate stack (50) that is surrounded by a dashed line in FIG. 7. The first region (A1) is a region that does not overlap with the front heat exchange section (40A) in the first direction. The first region (A1) is located in an upper portion and toward the front of the front plate stack (50).

[0076] As shown in FIG. 8, the branch flow path (70) has one inlet path (75), one branch path (76), two inlet paths (71, 72), one branch space (80), and three outlet paths (91, 92, 93).

[0077] The refrigerant in the refrigerant flow path (51) flows through the inlet path (75). An outlet end of the inlet path (75) communicates with a branch path (76). The branch path (76) has a first flow path (76a) and a second flow path (76b) that are parallel to each other. The branch path (76) divides the refrigerant into the first flow path (76a) and the second flow path (76b).

[0078] The inflow passages (71, 72) are passages for allowing the refrigerant to flow into the flow-division space (80). The two inflow passages (71, 72) are constituted by a first inflow passage (71) and a second inflow passage (72). An inflow end of the first inflow passage (71) is connected to the first flow path (76a). An inflow end of the second inflow passage (72) is connected to the second flow path (76b). An outlet (first outlet (O1)) located at an outflow end of the first inflow passage (71) is connected to the flow-division space (80). The first outlet (O1) opens toward the flow-division space (80). An outlet (second outlet (O2)) located at an outflow end of the second inflow passage (72) is connected to the flow-division space (80). The second outlet (O2) opens toward the flow-division space (80).

[0079] The flow dividing space (80) is a space for dividing the refrigerant into the respective outflow paths (91, 92, 93). The flow dividing space (80) is constituted by a second plate space (82), a first plate space (81), and a third plate space (83), which are successively arranged from the front side to the rear side.

[0080] The outflow channels (91, 92, 93) are channels into which the refrigerant diverted in the diversion space (80) flows. The three outflow channels (91, 92, 93) are composed of a first outflow channel (91), a second outflow channel (92), and a third outflow channel (93). An inflow port (first inflow port (I1)) located at an inflow end of the first outflow channel (91) connects to the diversion space (80). The first inflow port (I1) opens toward the diversion space (80). An inflow port (second inflow port (I2)) located at an inflow end of the second outflow channel (92) connects to the diversion space (80). The second inflow port (I2) opens toward the diversion space (80). An inflow port (third inflow port (I3)) located at an inflow end of the third outflow channel (93) connects to the diversion space (80). The third inlet (I3) opens toward the flow division space (80).

[0081] (4-2) Front plate configuration 7, the flow division flow path (70) is configured by connecting spaces formed in the second front plate (FP2), the third front plate (FP3), and the fourth front plate (FP4). The second front plate (FP2), the third front plate (FP3), and the fourth front plate (FP4) each form a plate space (81, 82, 83) and configure flow division plates adjacent to each other in the first direction. The first front plate (FP1) and the fifth front plate (FP5) configure closing plates for closing the flow division flow path (70).

[0082] The second front plate (FP2) corresponds to the first plate in which the first outlet (O1) is formed. The fourth front plate (FP4) corresponds to the second plate in which the second outlet (O2) is formed. The third front plate (FP3) is disposed between the second front plate (FP2) and the fourth front plate (FP4) and corresponds to the third plate in which the multiple inlets (I1, I2, I3) (in this example, the first inlet (I1), the second inlet (I2), and the third inlet (I3)) are formed.

[0083] (4-2-1) 3rd front plate 9, the third front plate (FP3) is formed with a branch path (76), a first plate space (81), a first outlet path (91), a second outlet path (92), and a third outlet path (93) as elements for forming the branch flow path (70). The branch path (76), the first plate space (81), the first outlet path (91), the second outlet path (92), and the third outlet path (93) are formed by holes penetrating the third front plate (FP3) in the thickness direction (first direction).

[0084] The branch path (76) is U-shaped when viewed from the first direction. A lower end of the branch path (76) communicates with the lead-in path (75). The first flow path (76a) extends forward and upward from the lower end of the branch path (76). The second flow path (76b) extends rearward and upward from the lower end of the branch path (76).

[0085] The first plate space (81) has a horizontally elongated shape extending in the third direction. In other words, the longitudinal direction of the first plate space (81) corresponds to the third direction. The first plate space (81) is formed in a rectangular parallelepiped shape.

[0086] The third front plate (FP3) is formed with a second outlet passage (92), a first outlet passage (91), and a third outlet passage (93) in that order from the front side to the rear side. The second outlet passage (92) is located near one end (front end) of the third plate space (83) in the third direction. The third outlet passage (93) is located near the other end (rear end) of the third plate space (83) in the third direction. The first outlet passage (91) is located in the middle of the third plate space (83) in the third direction.

[0087] The first outlet passage (91), the second outlet passage (92), and the third outlet passage (93) have a vertically elongated shape extending in the second direction. The inlets (I1, I2, I3) of the outlet passages (91, 92, 93) are connected to the third plate space (83). The inlets (I1, I2, I3) are located above the third plate space (83). The first outlet passage (91) has a greater vertical length than the second outlet passage (92) and the third outlet passage (93). The second outlet passage (92) and the third outlet passage (93) have approximately the same vertical length.

[0088] (4-2-2) Second front plate 10, the second front plate (FP2) is formed with an introduction passage (75), a first inflow passage (71), and a second plate space (82) as elements for forming the branch flow path (70). The introduction passage (75), the first inflow passage (71), and the second plate space (82) are formed by holes penetrating the second front plate (FP2) in the thickness direction (first direction).

[0089] The introduction path (75) is a part of the inflow path (71). In this embodiment, the introduction path (75) is curved in a U-shape. The outlet end of the introduction path (75) overlaps with the lower end (inflow end) of the branch path (76) in the first direction.

[0090] The second plate space (82) has a horizontally elongated shape extending in the third direction. In other words, the longitudinal direction of the second plate space (82) corresponds to the third direction. The first plate space (81) is formed in a rectangular parallelepiped shape.

[0091] The first inlet channel (71) has a vertically elongated shape extending in the second direction. The first outlet (O1), which is an outlet end of the first inlet channel (71), is continuous with the second plate space (82). The first inlet (I1) is located on the lower side of the first plate space (81). The first outlet (O1) is located near one end (near the front end) in the third direction of the second plate space (82). Specifically, the first outlet (O1) is located at one end (front end) of the second plate space (82) in the first direction. The first outlet (O1) is continuous with the other end of the second plate space (82) in the third direction without any step.

[0092] The second front plate (FP2) is formed with a first relay flow path (94), a second relay flow path (95), and a third relay flow path (96) as flow paths continuous with the branch flow path (70). The first relay flow path (94), the second relay flow path (95), and the third relay flow path (96) are formed by holes penetrating the second front plate (FP2) in the thickness direction (first direction).

[0093] An inflow end of the first relay flow path (94) overlaps with and communicates with one end (left end) in the first direction of the outflow end of the first outlet path (91). An inflow end of the second relay flow path (95) overlaps with and communicates with one end (left end) in the first direction of the outflow end of the second outlet path (92). An inflow end of the third relay flow path (96) overlaps with and communicates with one end (left end) in the first direction of the outflow end of the third outlet path (93).

[0094] (4-2-3) 4th front plate 11, the fourth front plate (FP4) is formed with a second inlet passage (72) and a third plate space (83) as elements for forming the branch flow path (70). The second inlet passage (72) and the third plate space (83) are formed by holes penetrating the fourth front plate (FP4) in the thickness direction (first direction).

[0095] The second inlet passage (72) has a vertically elongated shape extending in the second direction. The second outlet (O2), which is the outlet end of the second inlet passage (72), is continuous with the third plate space (83). The second inlet (I2) is located on the lower side of the second plate space (82). The second outlet (O2) is located near the other end (rear end) in the third direction of the third plate space (83). Specifically, the second outlet (O2) is located at one end (rear end) of the third plate space (83) in the first direction. The second outlet (O2) and the other end of the third plate space (83) in the third direction are continuous without any step.

[0096] The fourth front plate (FP4) is formed with a fourth relay flow path (97), a fifth relay flow path (98), and a sixth relay flow path (99) as flow paths continuing to the branch flow path (70). The fourth relay flow path (97), the fifth relay flow path (98), and the sixth relay flow path (99) are formed by holes penetrating the fourth front plate (FP4) in the thickness direction (first direction).

[0097] An inflow end of the fourth relay flow path (97) overlaps and communicates with the other end in the first direction (right end) of the outlet end of the first outlet path (91). An inflow end of the fourth relay flow path (97) overlaps and communicates with the other end in the first direction (right end) of the outlet end of the second outlet path (92). An inflow end of the fourth relay flow path (97) overlaps and communicates with the other end in the first direction (right end) of the outlet end of the third outlet path (93).

[0098] (4-4) Diversion space In the front plate laminate (50), a flow diversion space (80) is formed inside by laminating each plate (P). As shown in FIG. 8, the flow diversion space (80) is configured by the second plate space (82), the first plate space (81), and the third plate space (83) being continuous in the first direction. The first plate space (81), the second plate space (82), and the third plate space (83) overlap each other in the first direction. The first plate space (81), the second plate space (82), and the third plate space (83) preferably have the same shape. The first plate space (81), the second plate space (82), and the third plate space (83) preferably all overlap each other in the first direction.

[0099] The flow diversion space (80) is formed in a rectangular parallelepiped shape. Assuming the length of the flow diversion space (80) in the first direction is L1, the length in the second direction is L2, and the length in the third direction is L3, the flow diversion space (80) of the present embodiment satisfies the relationship of L2 < L1 < L3.

[0100] The length L2 of the flow diversion space (80) in the second direction is 1 mm or more and 6 mm or less. By setting L2 to 1 mm or more, the flow path resistance of the flow diversion space (80) can be reduced. By setting L2 to 6 mm or less, it is possible to prevent the distance between each outlet (O1, O2) and each inlet (I1, I2, I3) from becoming too long. L1 is preferably 9 mm or more, and L3 is preferably 15 mm or more. L1 and L3 are larger than the thickness of the flow diversion plates (FP2, FP3, FP4) (for example, 3 mm).

[0101] (4-5) Positional relationship between the outlets and each inlet FIG. 12 is a cross-sectional view of the flow diversion space. Each outlet (O1, O2) of each inflow path (71, 72) is formed on the lower surface (80a) that defines the flow diversion space (80). Each inlet (I1, I2, I3) of each outflow path (91, 92, 93) is formed on the upper surface (80b) that defines the flow diversion space (80). Each outlet (O1, O2) and each inlet (I1, I2, I3) are arranged on opposite sides with the flow diversion space (80) interposed therebetween.

[0102] The cross section of each of the outlets (O1, O2) is rectangular. The cross section of each of the outlets (O1, O2) is horizontally elongated extending in the third direction. In this manner, by extending each of the outlets (O1, O2) along the front and back surfaces of the plate (P) perpendicular to the flow direction, the flow path cross-sectional area of ​​each of the outlets (O1, O2) can be increased.

[0103] The first outlet (O1) is disposed at one end (left end) of the flow division space (80) in the first direction. The first outlet (O1) is disposed at one end (front end) of the flow division space (80) in the third direction. Thus, the first outlet (O1) is located at a corner of the flow division space (80) when viewed in the second direction. The first outlet (O1) is disposed so as to be flush with the left face (80d) and the front face (80e) that define the flow division space (80).

[0104] The second outlet (O2) is disposed at the other end (right end) of the flow division space (80) in the first direction. The second outlet (O2) is disposed at the other end (rear end) of the flow division space (80) in the third direction. Thus, the second outlet (O2) is located at a corner of the flow division space (80) when viewed in the second direction. The second outlet (O2) is disposed so as to be flush with the right face (80f) and the rear face (80c) that define the flow division space (80). The first outlet (O1) and the second outlet (O2) are located on opposite sides of the center of the flow division space (80) when viewed in the second direction.

[0105] The cross section of each of the inlets (I1, I2, I3) is rectangular. The cross section of each of the inlets (I1, I2, I3) is horizontally elongated extending in the third direction. In this manner, the flow path cross-sectional area of ​​the inlets (I1, I2, I3) can be enlarged by extending the inlets (I1, I2, I3) along the front and back surfaces of the plate (P) perpendicular to the flow direction. Each of the inlets (I1, I2, I3) is disposed in the middle of the flow division space (80) in the first direction. Each of the outlets (O1, O2) is located so as not to overlap with the center line (first center line (M1)) of the flow division space (80) in the first direction when viewed in the second direction.

[0106] The first inlet (I1) is located in the middle of the flow distribution space (80) in the third direction. The second inlet (I2) is located near one end (front end) of the flow distribution space (80) in the third direction. The third inlet (I3) is located near the other end (rear end) of the flow distribution space (80) in the third direction.

[0107] The inlets (I1, I2, I3) and the outlets (O1, O2) are offset from each other when viewed in the second direction. The inlets (I1, I2, I3) are disposed between the first outlet (O1) and the second outlet (O2) in the first direction of the flow division space (80). The inlets (I1, I2, I3) are disposed between the first outlet (O1) and the second outlet (O2) in the third direction of the flow division space (80).

[0108] (5) Driving behavior The air conditioner (10) performs a cooling operation, a heating operation, and a dehumidifying operation.

[0109] (5-1) Cooling operation In the cooling operation, the controller of the air conditioner (10) operates the compressor (21), the outdoor fan (25), and the indoor fan (32), sets the four-way switching valve (24) to the first state (the state shown by the solid line in FIG. 1), appropriately adjusts the opening degree of the outdoor expansion valve (23), and fully opens the indoor expansion valve (37).

[0110] In the cooling operation, the refrigerant circuit (11) performs a refrigeration cycle in which the outdoor heat exchanger (22) functions as a condenser (heat radiator) and the indoor heat exchanger (40) functions as an evaporator.

[0111] The indoor unit (30) draws indoor air from the indoor space (5) into the air passage (38) through the inlet (33). The air in the air passage (38) is cooled by the indoor heat exchanger (40). The cooled air is supplied to the indoor space (5) through the air outlet (34).

[0112] In the heat exchanger unit (U), the refrigerant that has flowed into the liquid relay pipe (67) flows into the front plate stack (50) of the front heat exchange section (40A). In the front heat exchange section (40A), the refrigerant absorbs heat from the indoor air while passing through the heat transfer tubes (42). The refrigerant then passes through the front plate stack (50) and flows into the first internal pipe (71a), and passes through the indoor expansion valve (37) and the second internal pipe (71b) in this order, and flows into the rear plate stack (60) of the rear heat exchange section (40B). In the rear heat exchange section (40B), the refrigerant absorbs heat from the indoor air while passing through the heat transfer tubes (42). The refrigerant then passes through the rear plate stack (60) and flows into the gas relay pipe (68), and flows out of the heat exchanger unit (U).

[0113] (5-2) Heating operation In the heating operation, the controller of the air conditioner (10) operates the compressor (21), the outdoor fan (25), and the indoor fan (32), sets the four-way switching valve (24) to the second state (the state shown by the dashed line in FIG. 1), adjusts the opening degree of the outdoor expansion valve (23) to a predetermined opening degree, and fully opens the indoor expansion valve (37).

[0114] In the heating operation, the refrigerant circuit (11) performs a refrigeration cycle in which the indoor heat exchanger (40) functions as a condenser (heat radiator) and the outdoor heat exchanger (22) functions as an evaporator.

[0115] The indoor unit (30) draws indoor air from the indoor space (5) into the air passage (38) through the inlet (33). The air in the air passage (38) is heated by the indoor heat exchanger (40). The heated air is supplied to the indoor space (5) through the air outlet (34).

[0116] In the heat exchanger unit (U), the refrigerant that has flowed into the gas relay pipe (68) flows into the rear plate stack (60) of the rear heat exchange section (40B). In the rear heat exchange section (40B), the refrigerant dissipates heat to the indoor air while passing through the heat transfer tubes (42). The refrigerant then flows through the rear plate stack (60) into the second internal pipe (71b), passes through the indoor expansion valve (37) and the first internal pipe (71a) in this order, and flows into the front plate stack (50) of the front heat exchange section (40A). In the front heat exchange section (40A), the refrigerant dissipates heat to the indoor air while passing through the heat transfer tubes (42). The refrigerant then flows through the front plate stack (50) into the liquid relay pipe (67), and flows out of the heat exchanger unit (U).

[0117] (5-3) Dehumidification operation In the dehumidification operation, a controller of the air conditioner (10) operates the compressor (21), the outdoor fan (25), and the indoor fan (32), sets the four-way switching valve (24) to the first state (the state shown by the solid line in FIG. 1), and appropriately adjusts the openings of the outdoor expansion valve (23) and the indoor expansion valve (37).

[0118] During dehumidification operation, the refrigerant circuit (11) performs a refrigeration cycle in which the outdoor heat exchanger (22) and the front heat exchange section (40A) of the indoor heat exchanger (40) function as a condenser (heat radiator), and the rear heat exchange section (40B) of the indoor heat exchanger (40) functions as an evaporator.

[0119] The indoor unit (30) draws room air from the indoor space (5) into the air passage (38) through the air inlet (33). The rear heat exchanger (40B) cools the air in the air passage (38) to a temperature equal to or lower than the dew point temperature. The front heat exchanger (40A) heats the air in the air passage (38). The air passing through both the rear heat exchanger and the front heat exchanger mix in the air passage (38) to become low-humidity air. The air dehumidified in this manner is supplied to the indoor space (5) through the air outlet (34).

[0120] In the heat exchanger unit (U), the refrigerant that has flowed into the liquid relay pipe (67) flows into the front plate stack (50) of the front heat exchange section (40A). In the front heat exchange section (40A), the refrigerant dissipates heat to the indoor air while passing through the heat transfer tubes (42). The refrigerant then passes through the front plate stack (50) and flows into the first internal pipe (71a), is reduced in pressure when passing through the indoor expansion valve (37), and then flows through the second internal pipe (71b) and into the rear plate stack (60) of the rear heat exchange section (40B). In the rear heat exchange section (40B), the refrigerant absorbs heat from the indoor air while passing through the heat transfer tubes (42). The refrigerant then passes through the rear plate stack (60) and flows into the gas relay pipe (68), and flows out of the heat exchanger unit (U).

[0121] (5-4) Flow in the branch channel When the air conditioner (10) is in operation, the refrigerant inside the front plate assembly (50) flows through the branch flow passage (70). An example of the flow of the refrigerant in the branch flow passage (70) will be described.

[0122] 8, the refrigerant flowing through the introduction passage (75) is divided into a first flow path (76a) and a second flow path (76b) at the branch passage (76). The refrigerant in the first flow path (76a) flows through the first inlet passage (71) and flows out from the first outlet (O1) into the flow-division space (80). The refrigerant in the second flow path (76b) flows through the second inlet passage (72) and flows out from the second outlet (O2) into the flow-division space (80).

[0123] In the flow division space (80), the refrigerant flowing out from both outlets (O1, O2) flows so as to sandwich the inlets (I1, I2, I3) from the first and third directions. The refrigerant flowing out from the first outlet (O1) flows not only into the second inlet (I2) but also into the first inlet (I1). The refrigerant flowing out from the second outlet (O2) flows not only into the third inlet (I3) but also into the first inlet (I1).

[0124] The refrigerant branched to the inlets (I1, I2, I3) of the third front plate (FP3) flows through the first outlet channel (91), the second outlet channel (92), and the third outlet channel (93). The refrigerant in the first outlet channel (91) of the third front plate (FP3) branches into the first relay channel (94) of the second front plate (FP2) and the fourth relay channel (97) of the fourth front plate (FP4). The refrigerant in the second outlet channel (92) of the third front plate (FP3) branches into the second relay channel (95) of the second front plate (FP2) and the fifth relay channel (98) of the fourth front plate (FP4). The refrigerant in the third outlet channel (93) of the third front plate (FP3) is branched into the third relay channel (96) of the second front plate (FP2) and the sixth relay channel (99) of the fourth front plate (FP4).

[0125] (6) Effects of the embodiment (6-1) The diversion flow path (70) includes a first inlet passage (71) and a second inlet passage (72) extending in a second direction along the vertical direction, a diversion space (80) connecting a first outlet (O1) of the first inlet passage (71) and a second outlet (O2) of the second inlet passage (72), and three or more outlet passages (91, 92, 93) each having an inlet (I1, I2, I3) connected to the diversion space (80) and extending in the second direction.

[0126] By connecting the two inflow channels (71, 72) to the flow-division space (80), the distance between the inflow channels (71, 72) and the outflow channels (91, 92, 93) can be made shorter than when one inflow channel is connected. As a result, the refrigerant can be prevented from being biased toward some of the outlets (O1, O2), and the flow-division performance of the flow-division channel (70) can be improved.

[0127] (6-2) The outlets (O1, O2) are disposed on the opposite side of the flow division space (80) to the inlets (I1, I2, I3). Compared to a case in which the outlets (O1, O2) and the inlets (I1, I2, I3) are located on the same side of the flow division space (80), the overall flow resistance of the flow division channel (70) can be reduced.

[0128] (6-3) The outlets (O1, O2) and the inlets (I1, I2, I3) are offset from each other when viewed in the second direction. Since the outlets (O1, O2) and a certain inlet (I1, I2, I3) do not overlap when viewed in the second direction, it is possible to prevent the refrigerant from being biased toward a certain inlet (I1, I2, I3).

[0129] (6-4) The multiple inlets (I1, I2, I3) are disposed between the first outlet (O1) and the second outlet (O2) when viewed from the second direction. Therefore, the refrigerant flowing out from the first outlet (O1) and the second outlet (O2) flows so as to sandwich the inlets (I1, I2, I3), thereby preventing the refrigerant from being biased toward some of the inlets (I1, I2, I3).

[0130] (6-5) The plurality of plates (P) includes a plurality of flow dividing plates (FP2, FP3, FP4) each having a plate space (81, 82, 83) formed therein and adjacent to each other in the first direction. The flow dividing space (80) is formed by the plate spaces (81, 82, 83) of the plurality of flow dividing plates (FP2, FP3, FP4) being continuous in the first direction.

[0131] Since the flow division space (80) extends across the plurality of flow division plates (FP2, FP3, FP4), the volume of the flow division space (80) can be made larger than when the flow division space (80) is formed on a single plate (P). This makes it easier to equalize the distances between the outlets (O1, O2) and the inlets (I1, I2, I3), thereby preventing the refrigerant from flowing toward some of the inlets (I1, I2, I3). As a result, the flow division performance of the flow division channel (70) can be improved. This effect is particularly noticeable when there are three or more outlet channels (91, 92, 93).

[0132] In addition, by forming the flow division space (80) using the plurality of plate spaces (81, 82, 83), the flow path cross-sectional area of ​​the flow division space (80) can be increased, and thus the flow velocity of the refrigerant can be reduced, thereby reducing the pressure loss of the refrigerant flowing through the flow division space (80).

[0133] (6-6) The first outlet (O1) and the second outlet (O2) are formed in different flow dividing plates (FP2, FP4). Therefore, the distance between the first outlet (O1) and the second outlet (O2) can be increased compared to when the first outlet (O1) and the second outlet (O2) are located on the same plate (P). As a result, the distance between the inflow channels (71, 72) and the outflow channels (91, 92, 93) can be reduced.

[0134] (6-7) The multiple distribution plates (FP2, FP3, FP4) include a second front plate (FP2) in which the first outlet (O1) is formed, a fourth front plate (FP4) in which the second outlet (O2) is formed, and a third front plate (FP3) arranged between the second front plate (FP2) and the fourth front plate (FP4) and in which at least one of the multiple inlets (I1, I2, I3) is formed.

[0135] In this configuration, the refrigerant flowing out from the first outlet (O1) and the second outlet (O2) flows so as to sandwich at least one of the inlets (I1, I2, I3) in the first direction, thereby preventing the refrigerant from being biased toward some of the inlets (I1, I2, I3).

[0136] In particular, in this embodiment, all of the inlets (I1, I2, I3) are formed in the third front plate (FP3). Therefore, the refrigerant flowing out from the first outlet (O1) and the second outlet (O2) flows so as to sandwich all of the inlets (I1, I2, I3) in the first direction, which makes it possible to prevent the refrigerant from being biased toward some of the inlets (I1, I2, I3).

[0137] (6-8) The branch passage (70) includes a branch passage (76) that branches the refrigerant into the first inlet passage (71) and the second inlet passage (72). The branch passage (76) is formed in the third front plate (FP3).

[0138] By forming a branch passage (76) in the third front plate (FP3) between the second front plate (FP2) and the fourth front plate (FP4), it becomes easier to divert the refrigerant from the branch passage (76) to the first outlet (O1) of the second front plate (FP2) and the second outlet (O2) of the fourth front plate (FP4).

[0139] (6-9) The flow division space (80) has a horizontally elongated shape extending in a third direction that is perpendicular to the first direction and parallel to the horizontal direction. The first outlet (O1) is disposed near one end of the flow division space (80) in the third direction. The second outlet (O2) is disposed near the other end of the flow division space (80) in the third direction.

[0140] The refrigerant flowing out from the first outlet (O1) and the second outlet (O2) flows so as to sandwich the inlets (I1, I2, I3) in the third direction, thereby preventing the refrigerant from being biased toward some of the inlets (I1, I2, I3).

[0141] (6-10) The number of the outflow channels (91, 92, 93) is preferably between 3 and 5. Even if the number of the outflow channels (91, 92, 93) is three, the flow division space (80) can be enlarged to prevent uneven flow of the refrigerant.

[0142] By limiting the number of the outlet channels (91, 92, 93) to five or less, the distances between the outlets (O1, O2) and the inlets (I1, I2, I3) can be prevented from becoming uneven, and the structures of the flow-diversion channel (70) and the plate stack (50, 60) can be prevented from becoming complicated.

[0143] Preferably, the number of outlet passages (91, 92, 93) is odd.

[0144] (6-11) The front plate stack (50) is formed with a first region (A1) that does not overlap with the front heat exchange section (40A) in the first direction. The flow division channel (70) is formed in the first region (A1).

[0145] If the branch flow passage (70) overlaps with the front heat exchange section (40A) in the first direction, it becomes difficult to ensure a region (second region) in the front plate stack (50) that is connected to the heat transfer tubes (42). In contrast, since the first region (A1) does not overlap with the front heat exchange section (40A) in the first direction, the second region can be sufficiently ensured.

[0146] (7) Variations The above-described embodiment may be modified as follows. The following describes the differences from the above-described embodiment.

[0147] (7-1) Variation 1 13, the first outlet (O1) is located slightly closer to the middle of the flow distribution space (80) than one end (front end) in the third direction. The second outlet (O2) is located slightly closer to the middle of the flow distribution space (80) than the other end (rear end) in the third direction.

[0148] (7-2) Variation 2 In the second modification shown in FIG. 14, only the first inlet (I1) is arranged on the third front plate (FP3). The second inlet (I2) is arranged on the fourth front plate (FP4), and the third inlet (I3) is arranged on the second front plate (FP2). The distance between the first outlet (O1) and each of the inlets (I1, I2, I3) in the third direction of the flow division space (80) is the smallest for the second inlet (I2) and the largest for the third inlet (I3). The distance between the second outlet (O2) and each of the inlets (I1, I2, I3) in the third direction of the flow division space (80) is the smallest for the third inlet (I3) and the largest for the second inlet (I2). The first outlet (O1) and the second outlet (O2) are arranged in a direction along the first diagonal of the flow division space (80). The first inlet (I1), the second inlet (I2), and the third inlet (I3) are arranged in the flow dividing space (80) in a direction along a second diagonal line intersecting the first diagonal line.

[0149] (7-3) Variation 3 In the third modification shown in FIG. 15, a plurality of outlets are formed in one and the same plate (P). In this example, the first outlet (O1) and the third outlet (O3) are formed in the second front plate (FP2), and the second outlet (O2) and the fourth outlet (O4) are formed in the fourth front plate (FP4). The fourth outlets (O1, O2) constitute the outlets of the fourth inlet. The third outlet (O3) is located near the other end (rear end) of the flow division space (80) in the third direction, and the fourth outlet (O4) is located near one end (front end) of the flow division space (80) in the third direction. Four or more inlets (O1, O2, O3, O4) (four in this example) are arranged to surround the plurality of inlets (I1, I2, I3).

[0150] (7-4) Variation 4 The plate stack (50, 60) of the fourth modification shown in FIG. 16 includes, in order from the side closer to the heat exchange section (40A), a first front plate (FP1), a second front plate (FP2), a third front plate (FP3), a fourth front plate (FP4), a fifth front plate (FP5), a sixth front plate (FP6), and a seventh front plate (FP7). The fourth front plate (FP4) has three first inlets (I1, I2, I3). The third front plate (FP3) has a first outlet (O1), and the fifth front plate (FP5) has a second outlet (O2). That is, the first outlet (O1) and the second outlet (O2) are located slightly closer to the middle than the ends in the first direction of the flow division space (80). In the fourth modification, the first outlet (O1) may be formed in the second front plate (FP2), and the second outlet (O2) may be formed in the sixth front plate (FP6).

[0151] (7-5) Variation 5 In the fifth modification shown in Fig. 17, plate spaces (81, 82, 83) are defined by grooves formed in the plate (P). The second front plate (FP2) has a second plate space (82) recessed in the first direction (leftward in Fig. 17) from the third front plate (FP3) side. The fourth front plate (FP4) has a second plate space (82) recessed in the first direction (rightward in Fig. 17) from the third front plate (FP3) side.

[0152] (8) Other embodiments In the above-described embodiment and each of the modified examples, the following configurations may be adopted.

[0153] In the branch flow path (70), the refrigerant may flow downward in the second direction through the inflow paths (71, 72) and the outflow paths (91, 92, 93).

[0154] The outlets (O1, O2) and the inlets (I1, I2, I3) may partially overlap in the second direction.

[0155] In the plate stack (50, 60), a flow dividing channel (70) may be formed in a region overlapping with the heat exchange section (40A) in the first direction.

[0156] The rear plate assembly (60) may have a flow splitter channel (70) formed therein.

[0157] The refrigeration cycle device (10) may be any device that performs a vapor compression refrigeration cycle and is not limited to an air conditioner. The refrigeration cycle device may be a cooling device that cools the interior of a refrigerator or a refrigerated warehouse, a chiller device that cools or heats a heat medium such as water, or a heat pump type water heater that heats water to generate hot water.

[0158] The air conditioner (10) does not have to be of a pair type, but may be of a multi-type.

[0159] The indoor unit (30) may be of a ceiling-mounted or floor-standing type.

[0160] The direction in which the front heat exchange section (40A) and the rear heat exchange section (40B) are arranged is not limited to the front-rear direction, and may be, for example, the up-down direction.

[0161] The valve connected to the intermediate pipe (66) does not have to be an expansion valve, and may be a solenoid valve, a check valve, a three-way valve, a four-way switching valve, a shutoff valve, or the like.

[0162] The heat exchanger unit (U) may be applied to an outdoor heat exchanger (22) of an outdoor unit (20).

[0163] The indoor heat exchanger (40) does not have to be of a fin-and-tube type and may be of, for example, a corrugated type in which corrugated fins are arranged between adjacent heat transfer tubes.

[0164] The heat exchanger body (B) may have one heat exchange section, not including the front heat exchange section (40A) and the rear heat exchange section (40B). In this case, a plate stack is provided corresponding to the one heat exchange section. The flow dividing passage (70) is formed in the plate stack.

[0165] The heat transfer tubes (42) and the fins (41) of the heat exchanger body (B) may be made of a copper material. In this case, the plate stack (50, 60) and the refrigerant pipes connected to the plate stack (50, 60) are preferably made of a copper material. The plate stack (50, 60) and the refrigerant pipes connected to the plate stack (50, 60) may be made of a stainless steel material.

[0166] Although the embodiment and modifications have been described above, it will be understood that various modifications in form and details are possible without departing from the spirit and scope of the claims. Elements of the above embodiment, modifications, and other embodiments may be appropriately combined or substituted.

[0167] The descriptions "first," "second," "third," etc. mentioned above are used to distinguish the words to which these descriptions are attached, and do not limit the number or order of the words. [Industrial Applicability]

[0168] INDUSTRIAL APPLICABILITY As described above, the present disclosure is useful for a heat exchanger unit, an air conditioner indoor unit, and a refrigeration cycle apparatus. [Explanation of symbols]

[0169] 10 Air conditioning equipment (refrigeration cycle equipment) 11 Refrigerant circuit 40A Front heat exchange section (heat exchange section) 41 Finn 42 Heat transfer tube 50 Plate stack 51 First refrigerant flow path (refrigerant flow path) 70 Diversion channel 71 1st inflow channel 72 Second inflow channel 76 Fork in the road 80 Diversion space 81, 82, 83 Plate Space 91,92,93 Outflow channel A1 1st area FP2 2nd front plate (1st plate, flow divider plate) FP3 3rd front plate (3rd plate, flow divider plate) FP4 4th front plate (2nd plate, flow divider plate) I1,I2,I3 Inlet O1 1st outlet O2 2nd outlet P-Plate U Heat Exchanger Unit

Claims

1. a heat exchange section (40A) having fins (41) and a heat transfer tube (42); a plate stack (50, 60) including a plurality of plates (P) stacked in a first direction along a horizontal direction, and in which a refrigerant flow path (51) communicating with the heat transfer tube (42) is formed; A flow dividing passage (70) for dividing a flow of a refrigerant is formed in the plate stack (50, 60), The branch flow passage (70) a first inlet channel (71) and a second inlet channel (72) extending in a second direction along the vertical direction; a flow dividing space (80) connecting a first outlet (O1) of the first inlet passage (71) and a second outlet (O2) of the second inlet passage (72); and a plurality of outlet paths (91, 92, 93) each having an inlet (I1, I2, I3) connected to the flow-division space (80) and extending in the second direction. Heat exchanger unit.

2. The first outlet (O1) and the second outlet (O2) are disposed on the opposite side in the second direction to the plurality of inlets (I1, I2, I3) across the flow division space (80).

2. The heat exchanger unit of claim 1.

3. The first outlet (O1) and the plurality of inlets (I1, I2, I3) are offset from each other when viewed from the second direction, The second outlet (O2) and the plurality of inlets (I1, I2, I3) are offset from each other when viewed from the second direction.

3. A heat exchanger unit according to claim 2.

4. The plurality of inlets (I1, I2, I3) are disposed between the first outlet (O1) and the second outlet (O2) when viewed from the second direction. A heat exchanger unit according to any one of claims 1 to 3.

5. The plurality of plates (P) each include a plurality of flow dividing plates (FP2, FP3, FP4) that are adjacent to each other in the first direction and each have a plate space (81, 82, 83), The flow distribution space (80) is formed by the plate spaces (81, 82, 83) of the plurality of flow distribution plates (FP2, FP3, FP4) continuing in the first direction. A heat exchanger unit according to any one of claims 1 to 3.

6. The first outlet (O1) and the second outlet (O2) are formed in different flow dividing plates (FP2, FP4).

6. A heat exchanger unit according to claim 5.

7. The plurality of flow dividing plates (FP2, FP3, FP4) are a first plate (FP2) in which the first outlet (O1) is formed; a second plate (FP4) in which the second outlet (O2) is formed; a third plate (FP3) disposed between the first plate (FP2) and the second plate (FP4), and in which at least one of the plurality of inlets (I1, I2, I3) is formed.

7. A heat exchanger unit according to claim 6.

8. The third plate (FP3) has all of the inlets (I1, I2, I3) formed therein. A heat exchanger unit according to claim 7.

9. The branch passage (70) includes a branch passage (76) that branches the refrigerant into the first inlet passage (71) and the second inlet passage (72), The branch passage (76) is formed in the third plate (FP3).

9. A heat exchanger unit according to claim 8.

10. The flow division space (80) has a horizontally elongated shape extending in a third direction perpendicular to the first direction and aligned along the horizontal direction, The first outlet (O1) is disposed toward one end of the flow distribution space (80) in the third direction, The second outlet (O2) is disposed toward the other end of the flow distribution space (80) in the third direction. A heat exchanger unit according to any one of claims 1 to 3.

11. The number of outlet channels (91, 92, 93) is five or less. A heat exchanger unit according to any one of claims 1 to 3.

12. The plate stack (50, 60) is formed with a first region (A1) that does not overlap with the heat exchange section (40A), The branch flow passage (70) is formed in the first region (A1). A heat exchanger unit according to any one of claims 1 to 3.

13. An air conditioning indoor unit comprising a heat exchanger unit (U) according to any one of claims 1 to 3.

14. A refrigerant circuit (11) to which the heat exchanger unit (U) according to any one of claims 1 to 3 is connected. Refrigeration cycle equipment.

Images