Heat exchanger unit, air conditioning indoor unit, and refrigeration cycle system

Abstract

To improve flow dividing performance of a heat exchanger unit comprising a flow dividing passage.SOLUTION: A flow dividing passage (70) includes: an inflow passage (71) extending in a second direction along a vertical direction; a flow dividing space (80) to which an outflow port (O) of the inflow passage (71) is connected; and a plurality of 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. A plurality of plates (P) include a plurality of flow dividing plates (FP2, FP3, and FP4) in which plate spaces (81, 82, and 83) are formed respectively, and which is adjacent to each other in a first direction. The flow dividing space (80) is formed in such a manner that the respective plate spaces (81, 82, and 83) of the plurality of flow dividing plates (FP2, FP3, and FP4) are continuous in the first direction.SELECTED DRAWING: Figure 8

Description

Technical Field

[0003] ,

[0001] The present disclosure relates to a heat exchanger unit, an air conditioner indoor unit, and a refrigeration cycle device.

Background Art

[0002] Patent Document 1 discloses a header provided in a heat exchanger. The header of Patent Document 1 is configured by laminating a plurality of plates. As shown in FIG. 6 of Patent Document 1, a space (diversion space) for diverting refrigerant is formed inside the header. One inflow path and a plurality of outflow paths are connected to the diversion space. The refrigerant flowing into the diversion space from the inflow path is diverted to the plurality of outflow paths. The refrigerant diverted to each outflow path is supplied to each heat transfer tube of the heat exchanger.

Prior Art Documents

Patent Documents

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In the diversion structure as described in Patent Document 1, if the refrigerant is unevenly distributed to some of the outflow paths, the performance of the heat exchanger will deteriorate.

[0005] An object of the present disclosure is to improve the diversion performance of a heat exchanger unit having a diversion flow path.

Means for Solving the Problems

[0006] The first embodiment relates 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) having a plurality of plates (P) stacked in a first direction along the horizontal direction, and having a refrigerant flow path (51) that communicates with the heat transfer tubes (42). A flow diversion channel (70) for diverting the refrigerant is formed in the plate stack (50). The flow diversion channel (70) includes an inlet passage (71) extending in a second direction along the vertical direction, a diversion space (80) to which the outlet (O) of the inlet passage (71) is connected, and a plurality of outlet passages (91, 92, 93) extending in the second direction, each having inlets (I1, I2, I3) that connect to the diversion space (80). Each of the multiple plates (P) has a plate space (81, 82, 83) formed in it, and includes multiple diversion plates (FP2, FP3, FP4) adjacent in the first direction. The diversion space (80) is formed by the continuity of each plate space (81, 82, 83) of the multiple diversion plates (FP2, FP3, FP4) in the first direction.

[0007] In the first embodiment, multiple flow dividers (FP2, FP3, FP4) are stacked in a first direction, so that the plate spaces (81, 82, 83) of each flow divider (FP2, FP3, FP4) are continuous in the first direction. As a result, in the heat exchanger unit, a flow divider space (80) is formed by multiple plate spaces (81, 82, 83). Since the flow divider space (80) spans multiple plates (P) rather than just one plate (P), the volume of the space expands in the first direction (stacking direction) of the plates (P). Therefore, it is possible to suppress large differences in the distance between the outlet (O) of the inlet passage (71) and the inlets (I1, I2, I3) of the multiple outlet passages (91, 92, 93). As a result, it is possible to suppress large differences in flow resistance between the outlet (O) and each inlet (I1, I2, I3), thus suppressing the refrigerant from flowing unevenly to some of the outlet passages (91, 92, 93).

[0008] In the second embodiment, the outlet (O) is located on the opposite side of the inlet (I1, I2, I3) from the flow separation space (80).

[0009] In the second embodiment, the flow resistance of the refrigerant flowing through the flow separation space (80) can be reduced.

[0010] In the third aspect, as in the second aspect, the outlet (O) and inlets (I1, I2, I3) are offset from each other when viewed from the second direction.

[0011] In the third embodiment, since the outlet (O) and certain inlets (I1, I2, I3) do not overlap when viewed in the second direction, it is possible to suppress the refrigerant from flowing unevenly towards certain inlets (I1, I2, I3).

[0012] The fourth embodiment is one of the first to third embodiments in which at least two of the multiple inlets (I1, I2, I3) are formed on different flow dividers (FP2, FP3, FP4).

[0013] In the fourth embodiment, since at least two of the multiple inlets (I1, I2, I3) are not formed on the same flow divider plate (FP2, FP3, FP4), it is possible to suppress large differences in the distance between the outlet (O) and these inlets (I1, I2, I3).

[0014] The fifth aspect is the same as the fourth aspect, in which there are three or more inlets (I1, I2, I3), and at least three of the inlets (I1, I2, I3) are formed on different flow dividers (FP2, FP3, FP4).

[0015] In the fifth embodiment, since at least three of the three or more inlets (I1, I2, I3) are not formed on the same flow divider plate (FP2, FP3, FP4), it is possible to suppress large differences in the distance between the outlet (O) and these inlets (I1, I2, I3).

[0016] The sixth embodiment is a plurality of flow dividers (FP2, FP3, FP4) in any one of the first to fifth embodiments, comprising: a first plate (FP3) on which an outlet (O) is formed; a second plate (FP2) positioned on one end of the first plate (FP3) in the thickness direction and on which inlets (I1, I2, I3) are formed; and a third plate (FP4) positioned on the other end of the first plate (FP3) in the thickness direction and on which inlets (I1, I2, I3) are formed.

[0017] In the sixth embodiment, the refrigerant flowing out from the outlet (O) of the first plate (FP3) is divided into two flows: one end and the other end in the thickness direction of the first plate (FP3). The refrigerant that flows to one end flows into the inlet (I1, I2, I3) of the second plate (FP2), and the refrigerant that flows to the other end is divided and flows into the inlet (I1, I2, I3) of the third plate (FP4). Thus, the inlet (I1, I2, I3) of the second plate (FP2) and the inlet (I1, I2, I3) of the third plate (FP4) are located on opposite sides of the first plate (FP3). This makes it possible to suppress large differences in the distance between the outlet (O) of the first plate (FP3) and the inlets (I1, I2, I3) of the second plate (FP2), and between the outlet (O) of the first plate (FP3) and the inlets (I1, I2, I3) of the third plate (FP4).

[0018] The seventh aspect is that, in any one of the first to sixth aspects, the plate space (81, 82, 83) has a horizontally elongated shape when viewed in the second direction, extending in a third direction that is perpendicular to the first direction and along the horizontal direction.

[0019] In the seventh embodiment, each plate space (81, 82, 83) of the multiple flow-diverting plates (FP2, FP3, FP4) is formed in a horizontally elongated shape that extends in the third direction. As a result, the volume of the flow-diverting space (80) formed by the continuity of these flow-diverting plates (FP2, FP3, FP4) can be increased.

[0020] The eighth aspect is that, in any one of the first to seventh aspects, the plate spaces (81, 82, 83) are holes penetrating the splitting plates (FP2, FP3, FP4) in the thickness direction.

[0021] In the eighth aspect, the plate spaces (81, 82, 83) are formed by the holes in the splitting plates (FP2, FP3, FP4). Therefore, the plate spaces (81, 82, 83) can be extended in the thickness direction of the splitting plates (FP2, FP3, FP4).

[0022] The ninth aspect is that, in the eighth aspect, the plate spaces (81, 82, 83) have the same shape as each other.

[0023] In the ninth aspect, it becomes easier to process the splitting space (80).

[0024] The tenth aspect is that, in the seventh aspect, the outlet (O) is arranged at the middle part in the third direction of the splitting space (80), and the inlets (I1, I2, I3) are arranged near the ends in the third direction of the splitting space (80).

[0025] In the tenth aspect, it is possible to suppress the shortening of the distance between the outlet (O) and the inlets (I1, I2, I3), and it is possible to suppress the uneven flow of the refrigerant to the inlets (I1, I2, I3).

[0026] The eleventh aspect is that, in any one of the first to tenth aspects, a reducing portion (75a) for reducing the flow path cross-section is formed in the inflow path (71) as approaching the downstream side.

[0027] In the eleventh aspect, as the refrigerant flows through the reducing portion (75a) of the inflow path (71), the flow velocity of the refrigerant increases. By increasing the flow velocity of the refrigerant, it is possible to suppress the uneven flow of the refrigerant to some of the outflow paths (91, 92, 93).

[0028] The twelfth aspect is that, in any one of the first to eleventh aspects, the plurality of outflow paths (91, 92, 93) are three or more and five or less.

[0029] In the twelfth embodiment, even if there are three or more outflow channels (91, 92, 93), the flow separation performance can be improved by the flow separation space (80). By limiting the number of outflow channels (91, 92, 93) to five or fewer, it is possible to suppress the deterioration of flow separation performance caused by increasing the number of outflow channels (91, 92, 93).

[0030] The 13th embodiment is one of the first to 12 embodiments in which the length of the flow separation space (80) in the second direction is 1 mm or more and 6 mm or less.

[0031] In the 13th embodiment, since the length of the diversion space (80) in the second direction is 1 mm or more, the flow resistance of the diversion space (80) can be reduced. Since the length of the diversion space (80) in the second direction is 6 mm or less, the uneven flow of the refrigerant to some of the outlet passages (91, 92, 93) can be suppressed.

[0032] In the 14th embodiment, in any one of the first to 13 embodiments, a first region (A1) is formed in the plate stack (50) that does not overlap with the heat exchange section (40A) in the first direction, and a flow diversion channel (70) is formed in the first region (A1).

[0033] In the 14th embodiment, interference between the heat transfer tubes (42) of the heat exchange section (40A) and the flow diversion channel (70) in the first direction can be suppressed.

[0034] The 15th embodiment is an air conditioning indoor unit equipped with a heat exchanger unit (U) according to any one of the 1st to 14th embodiments.

[0035] The sixteenth embodiment is a refrigeration cycle system comprising a refrigerant circuit (11) to which a heat exchanger unit (U) of any one of the first to fourteen embodiments is connected. [Brief explanation of the drawing]

[0036] [Figure 1] Figure 1 is a piping diagram of an air conditioning system according to an embodiment. [Figure 2] Figure 2 is a front view of the indoor unit of the air conditioner. [Figure 3] Figure 3 is a cross-sectional view of the AA line of the indoor unit of the air conditioner. [Figure 4] Figure 4 is a front view showing the internal structure of an indoor air conditioning unit. [Figure 5] Figure 5 is a cross-sectional view showing the connection structure between the heat transfer tubes and the plate stack. [Figure 6] Figure 6 is a perspective view of the main components of the heat exchanger unit. [Figure 7] Figure 7 is an exploded perspective view of the front plate stack. [Figure 8] Figure 8 is a perspective view of the main part of the diversion channel. [Figure 9] Figure 9 is an enlarged side view of the diversion channel of the third front plate, corresponding to the area enclosed by the dashed line R9 in Figure 7. [Figure 10] Figure 10 is an enlarged side view of the diversion channel of the second front plate, corresponding to the area enclosed by the dashed line R10 in Figure 7. [Figure 11] Figure 11 is an enlarged side view of the diversion channel of the fourth front plate, corresponding to the area enclosed by the dashed line R11 in Figure 7. [Figure 12] Figure 12 is a cross-sectional view of the diversion channel. [Figure 13] Figure 13 is a cross-sectional view of the diversion channel in Modification 1. [Figure 14] Figure 14 is a cross-sectional view of the diversion channel in the modified example 2. [Figure 15] Figure 15 is a cross-sectional view of the diversion channel in the modified example 3. [Figure 16] Figure 16 is a cross-sectional view of the diversion channel in the modified example 4. [Figure 17] Figure 17 is a cross-sectional view of the diversion channel in Modification 5. [Modes for carrying out the invention]

[0037] The embodiments of this disclosure will be described in detail below with reference to the drawings. However, this disclosure is not limited to the embodiments shown below, and various modifications are possible without departing from the technical idea of ​​this disclosure. Since the drawings are for conceptual illustration of this disclosure, dimensions, ratios, or numbers may be exaggerated or simplified as necessary for ease of understanding.

[0038] (1) Overall configuration of the air conditioning system This embodiment is an air conditioning system (10) equipped with a heat exchanger unit (U). The air conditioning system (10) adjusts the temperature of the air in the target space, which is an indoor space (5).

[0039] As shown in Figure 1, the air conditioning system (10) is an example of a refrigeration cycle system equipped with a refrigerant circuit (11). The refrigerant circuit (11) is filled with refrigerant. The refrigerant circuit (11) performs a refrigeration cycle by circulating the refrigerant.

[0040] The air conditioning system (10) comprises an outdoor unit (20), an indoor unit (30), a first connecting pipe (12), and a second connecting pipe (13). The air conditioning system (10) is a paired system 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 conditioning system (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).

[0041] The outdoor unit (20) is installed outdoors. The outdoor unit (20) 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).

[0042] The compressor (21) is a rotary compressor such as an oscillating piston type, rotary type, or scroll type. The outdoor heat exchanger (22) exchanges heat between the refrigerant and the outdoor air. The outdoor heat exchanger (22) is a fin-and-tube type 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 (shown by the solid line in Figure 1) and a second state (shown by the dashed line in Figure 1). In the first state, the four-way switching valve (24) connects the discharge part of the compressor (21) to the gas end of the outdoor heat exchanger (22), and also connects the suction part of the compressor (21) to the first connecting pipe (12). The four-way switching valve (24) in the second state connects the discharge section of the compressor (21) to the first connecting pipe (12), and also connects the suction section of the compressor (21) to 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.

[0043] The indoor unit (30) comprises 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).

[0044] (2) Indoor unit Details of the indoor unit (30), which is an indoor air conditioner, will be explained with reference to Figures 2 to 4. The indoor unit (30) in this embodiment is a wall-mounted type installed on the wall of the indoor space (5). The terms "up," "down," "right," "left," "front," and "rear" described below correspond to the directions of the arrows shown in Figures 2 and 3, and indicate the direction when viewing the casing (31) from the front.

[0045] (2-1) Casing The casing (31) is formed in a horizontally elongated box shape from left to right. The casing (31) 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).

[0046] 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 top plate (31c) is formed on the upper side of the casing (31) and constitutes the upper surface of the casing (31). The bottom 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).

[0047] An intake port (33) is formed in the upper plate (31c), and an outlet port (34) is formed in the lower plate (31d). Inside the casing (31), an air passage (38) is formed from the intake port (33) to the outlet 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 drawing air from the indoor space (5) into the air passage (38). An outlet port (34) is formed in the lower plate (31d). The outlet port (34) extends in the longitudinal direction of the casing (31). The outlet port (34) is an opening for blowing air from the air passage (38) into the indoor space (5).

[0048] (2-2) Filter The indoor unit (30) is equipped with a filter (35). The filter (35) is located behind the intake port (33) and upstream of the indoor heat exchanger (40). The filter (35) collects dust from the air sent from the intake port (33) to the indoor heat exchanger (40). The indoor unit (30) may also be equipped with a dust removal mechanism to remove the dust collected by the filter (35).

[0049] (2-3) Heat exchange unit The heat exchanger unit (U) comprises an indoor heat exchanger (40), intermediate piping (66), an indoor expansion valve (37), a liquid relay pipe (67), and a gas relay pipe (68). The indoor heat exchanger (40) comprises a heat exchanger body (B) and two plate stacks (50, 60) connected to the heat exchanger body (B). Details of these will be described later.

[0050] (2-4) Indoor fan The indoor fan (32) is positioned in the air passage (38). The indoor fan (32) is positioned downstream of the indoor heat exchanger (40) in the air passage (38). The indoor fan (32) is a cross-flow fan. The fan rotor of the indoor fan (32) extends in the longitudinal direction of the casing (31).

[0051] (2-5) Flap The indoor unit (30) has a flap (36) that adjusts the direction of the air blown out from the air outlet (34). The flap (36) adjusts the airflow direction in the vertical direction. The indoor unit (30) may have multiple flaps (36). The flaps (36) may also adjust the airflow direction in the horizontal direction.

[0052] (3) Details of the indoor heat exchanger The indoor heat exchanger (40) will be described in detail with reference to Figures 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 type air heat exchanger. The indoor heat exchanger (40) comprises a heat exchanger body (B) and two plate stacks (50) connected to the heat exchanger body (B).

[0053] (3-1) Heat exchanger body As shown in Figures 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 direction of the arrangement of the fins (41). The plate stacks (50, 60) have refrigerant flow paths (51, 61) inside that communicate with the heat transfer tubes (42).

[0054] The direction of arrangement of the fins (41) corresponds to the longitudinal direction (in this case, left-right direction) of the casing (31). The fins (41) are rectangular plates with a long side and a short side. The thickness direction of the fins (41) corresponds to the direction of arrangement of the fins (41). Multiple fins (41) are arranged at predetermined intervals in their thickness direction. This interval constitutes an airflow channel. The material of the fins (41) is an aluminum alloy.

[0055] The material of the multiple heat transfer tubes (42) is an aluminum alloy. Coolant flow paths are formed inside the heat transfer tubes (42). The multiple heat transfer tubes (42) extend parallel to each other so as to penetrate the fins (41). One end of the heat transfer tube (42), the right end, protrudes to the right of the fins (41). One end of the heat transfer tube (42) is connected to the plate stack (50, 60). Of the other ends of the multiple heat transfer tubes (42), 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 as a single, seamless unit.

[0056] 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 towards the front of the casing (31), and the rear heat exchange section (40B) is located towards the rear of the casing (31). The front heat exchange section (40A) and the rear heat exchange section (40B) are arranged in the front-to-back direction, sandwiching the indoor fan (32). The front-to-back direction is perpendicular to the axial direction and vertical direction of the heat transfer tubes (42).

[0057] 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).

[0058] The front main heat exchange section (43) is positioned closer to the indoor fan (32) in the front heat exchange section (40A). The outer shape of the front main heat exchange section (43) is formed in a V shape when viewed in the axial direction of the heat transfer tubes (42). The tip of this V shape points forward. The fins (41) constituting the front main heat exchange section (43) have a first portion (41a) that extends diagonally upward toward the rear and a second portion (41b) that extends diagonally downward toward the rear. The angle between the direction of extension of the first portion (41a) and the direction of extension of the second portion (41b) is approximately 90° to 110°. The first portion (41a) and the second portion (41b) may be formed as a single unit or as separate parts.

[0059] 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 and short sides of the fins (41) of the first auxiliary heat exchange section (44) are shorter than the lengths of the fins (41) of the first front main heat exchange section (43a). The number of stages in the direction along the long side of the heat transfer tubes (42) in the first auxiliary heat exchange section (44) is less than the number of stages of the heat transfer tubes (42) in the first front main heat exchange section (43a). The number of rows in the direction along the short side of the heat transfer tubes (42) in the first auxiliary heat exchange section (44) is less than the number of rows of the heat transfer tubes (42) in the first front main heat exchange section (43a).

[0060] The second auxiliary heat exchange section (45) is located on the inlet side (front side) of the second front main heat exchange section (43b). The lengths of the long and 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 heat transfer tubes (42) in the second auxiliary heat exchange section (45) is less than the number of stages and rows of heat transfer tubes (42) in the second front main heat exchange section (43b).

[0061] The rear heat exchange section (40B) comprises a rear main heat exchange section (46) and a third auxiliary heat exchange section (47). The rear main heat exchange section (46) is positioned closer to the indoor fan (32) in the rear heat exchange section (40B). The third auxiliary heat exchange section (47) is located 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 heat transfer tubes (42) in the third auxiliary heat exchange section (47) are fewer than the number of stages and rows of heat transfer tubes (42) in the rear main heat exchange section (46).

[0062] As shown in Figure 5, one end of the heat transfer tube (42) has a flared portion (48). The flared portion (48) has an enlarged diameter portion (48a) that increases in diameter as it approaches the plate stack (50, 60), and a cylindrical portion (48b) of the same diameter that extends axially from the end of the enlarged diameter portion (48a) on the plate stack (50, 60) side. As will be described in more detail later, the flared portion (48) is the part that connects to the heat transfer tube side connection portion (53, 63) of the plate stack (50, 60).

[0063] (3-2) Plate Laminate The plate stack (50,60) is positioned to the right of the rightmost fin (41), parallel to the fin (41). The plate stack (50,60) is connected to one end of the heat transfer tube (42). As shown in Figure 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 positioned to overlap with the front heat exchange section (40A) in the axial direction of the heat transfer tube (42). The rear plate stack (60) is positioned to overlap with the rear heat exchange section (40B) in the axial direction of the heat transfer tube (42).

[0064] (3-2-1) Front plate stack The front plate stack (50) has a front main body (52) having a refrigerant flow path (more precisely, a first refrigerant flow path (51)) inside, and a plurality of front connection parts (53) that connect a plurality of heat transfer tubes (42) of the front heat exchange section (40A) to the first refrigerant flow path (51).

[0065] As shown in Figures 5 to 7, the front main body (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 tube (42).

[0066] In the front plate stack (50), the first front plate (FP1), the second front plate (FP2), the third front plate (FP3), the fourth front plate (FP4), and the 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 side opposite 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 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, plate-shaped members with a common 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, the material of each front plate is an aluminum alloy. The thickness of the first front plate (FP1) and the fifth front plate (FP5) is 1.5 mm. The thickness of the second front plate (FP2), the third front plate (FP3), and the fourth front plate (FP4) is 3.0 mm. Each front plate is joined to each other by furnace brazing. Note that the number of front plates is just an example; the number of front plates may be four or fewer, or six or more. Hereafter, when it is not necessary to distinguish between each front plate, they will simply be referred to as "front plates."

[0067] (3-2-2) Rear plate stack The rear plate stack (60) has a rear main body (62) having a refrigerant flow path (more precisely, a second refrigerant flow path (61)) inside, and a plurality of rear connection parts (63) that connect a plurality of heat transfer tubes (42) of the rear heat exchange section (40B) to the second refrigerant flow path (61).

[0068] As shown in Figures 5 and 6, the rear main body (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 tube (42).

[0069] In the rear plate stack (60), the first rear plate (BP1), the second rear plate (BP2), the third rear plate (BP3), the fourth rear plate (BP4), and the 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 side opposite 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, plate-shaped members with a common outer edge shape. Each rear plate is made of the same material as the heat transfer tubes (42) and rear connection parts (63). In this embodiment, the material of each rear plate is an aluminum alloy. The thickness of the first rear plate (BP1) and the fifth rear plate (BP5) is 1.5 mm. The thickness of the second rear plate (BP2), the third rear plate (BP3), and the fourth rear plate (BP4) is 3.0 mm. Each rear plate is joined to each other by furnace brazing. Note that the number of rear plates is just an example; the number of rear plates may be four or fewer, or six or more. Hereafter, when there is no need to distinguish between each rear plate, they will simply be referred to as rear plates. Furthermore, the front plates and rear plates will be collectively referred to as plates (P).

[0070] (3-2-3) Heat transfer tube side connection As shown in Figure 5, the plate stack (50, 60) has a plurality of front connection parts (53) and a plurality of rear connection parts (63). The plurality of front connection parts (53) are provided on the front plate stack (50), and the plurality of rear connection parts (63) are provided on the rear plate stack (60). When it is not necessary to distinguish between the front connection parts (53) and the rear connection parts (63), they are also called heat transfer tube side connection parts (53, 63).

[0071] 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).

[0072] 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).

[0073] The heat transfer tube side connector (53, 63) is a cylindrical tube. The material of the heat transfer tube side connector (53, 63) is an aluminum alloy. As shown in Figure 5, the tip of the heat transfer tube side connector (53, 63) is inserted into the end of the corresponding heat transfer tube (42). In other words, the end of the heat transfer tube (42) is externally fitted onto the heat transfer tube side connector (53, 63). The heat transfer tube side connector (53, 63) is inserted into the flared portion (48) of the corresponding heat transfer tube (42). The heat transfer tube side connector (53, 63) is inserted into the flared portion (48) and joined to the cylindrical portion (48b) of the flared portion (48) by burner brazing.

[0074] (3-3) Intermediate piping As shown in Figure 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, an indoor expansion valve (37) is connected to the intermediate pipe (66).

[0075] 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 the front main body (52) on the side opposite to the front heat exchange section (40A). One end of the intermediate pipe (66) communicates with 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 the rear main body (62) on the side opposite to the rear heat exchange section (40B). The other end of the intermediate pipe (66) communicates with the second refrigerant flow path (61).

[0076] (3-4) Indoor expansion valve The indoor expansion valve (37) is located on the right side of the heat exchanger body (B). The indoor expansion valve (37) is connected to the intermediate piping (66). The indoor expansion valve (37) reduces the pressure of the refrigerant flowing through the intermediate piping (66). The indoor expansion valve (37) is an electronic expansion valve.

[0077] (3-5) Liquid transfer tube As shown in Figure 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 a second connecting pipe (13), which is a liquid connecting pipe, outside the casing (31).

[0078] (3-6) Gas relay pipe As shown in Figure 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 stack (60). The other end of the gas relay pipe (68) is connected to the first connecting pipe (12), which is a gas connecting pipe, outside the casing (31).

[0079] (4) Diversion channel A flow divider channel (70) is formed in the front plate stack (50). The flow divider channel (70) is part of the first refrigerant channel (51). The flow divider channel (70) divides the refrigerant within the front plate stack (50). The details of the flow divider channel (70) will be explained in detail with reference to Figures 6 to 12. In the following explanation, the first direction corresponds to the stacking direction of the plates (P) (left-right direction in Figure 6), the second direction corresponds to the direction along the vertical direction (up-down direction in Figure 6), and the third direction corresponds to the direction perpendicular to the first direction and along the horizontal direction (front-back direction in Figure 6).

[0080] (4-1) Basic configuration of diversion channels The flow diversion channel (70) is formed by stacking multiple plates (P). The flow diversion channel (70) is located in the first region (A1) enclosed by the dashed line in Figure 7 in the front plate stack (50). 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 the upper part of the front plate stack (50) and closer to the front.

[0081] As shown in Figure 8, the diversion channel (70) has one inflow channel (71), one diversion space (80), and three outflow channels (91, 92, 93).

[0082] The inlet passage (71) is a flow path for introducing refrigerant into the diversion space (80). The outlet (O), located at the outlet end of the inlet passage (71), connects to the diversion space (80). The outlet (O) opens toward the diversion space (80).

[0083] The flow division space (80) is a space for dividing the refrigerant into each outlet passage (91, 92, 93). The flow division space (80) is composed of a second plate space (82), a first plate space (81), and a third plate space (83), which are continuous in order from the front to the rear.

[0084] The outflow passages (91, 92, 93) are the flow paths through which the refrigerant, which has been divided in the flow separation space (80), flows in. The three outflow passages (91, 92, 93) consist of the first outflow passage (91), the second outflow passage (92), and the third outflow passage (93). The inlet located at the inflow end of the first outflow passage (91) (first inlet (I1)) connects to the flow separation space (80). The first inlet (I1) opens toward the flow separation space (80). The inlet located at the inflow end of the second outflow passage (92) (second inlet (I2)) connects to the flow separation space (80). The second inlet (I2) opens toward the flow separation space (80). The inlet located at the inflow end of the third outflow passage (93) (third inlet (I3)) connects to the flow separation space (80). The third inlet (I3) opens toward the diversion space (80).

[0085] (4-2) Configuration of the front plate As shown in Figure 7, the diversion channel (70) is composed of a continuous space 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 constitute diversion plates adjacent to each other in the first direction. The first front plate (FP1) and the fifth front plate (FP5) constitute blocking plates for blocking the diversion channel (70).

[0086] The third front plate (FP3) corresponds to the first plate. The second front plate (FP2) corresponds to the second plate located on one end of the third front plate (FP3) in the thickness direction (left side in Figure 6). The fourth front plate (FP4) corresponds to the third plate located on the other end of the third front plate (FP3) in the thickness direction (right side in Figure 6). The third front plate (FP3) is located between the second front plate (FP2) and the fourth front plate (FP4).

[0087] (4-2-1) Third front plate As shown in Figure 9, the third front plate (FP3) has an inflow relay channel (75), a first plate space (81), and a first outflow channel (91) formed as elements for constituting a flow diversion channel (70). The inflow relay channel (75), the first plate space (81), and the first outflow channel (91) are formed by holes that penetrate the third front plate (FP3) in the thickness direction (first direction).

[0088] The inflow relay channel (75) constitutes a part of the inflow channel (71). The inflow relay channel (75) extends in a second direction. The inflow end (lower end) of the inflow relay channel (75) is formed in a substantially circular shape. The inflow relay channel (75) has a narrowing section (75a) that reduces the flow path cross-sectional area as it moves downstream (upper part of Figure 9). The narrowing section (75a) is formed in a tapered shape that reduces the length (hereinafter also referred to as width) in a third direction in the inflow channel (71) as it moves downstream. The outflow section of the inflow relay channel (75) is formed in a rectangular parallelepiped shape.

[0089] The first plate space (81) has a transversely elongated shape that extends 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 the shape of a rectangular parallelepiped.

[0090] The outlet (O), which is the outflow end of the inflow relay path (75), is continuous with the first plate space (81). The outlet (O) is located below the first plate space (81). The outlet (O) is located in the middle of the third direction within the first plate space (81).

[0091] The first outflow channel (91) has a vertically elongated shape extending in the second direction. The first inlet (I1), which is the inflow end of the first outflow channel (91), is continuous with the first plate space (81). The first inlet (I1) is located on the upper side of the first plate space (81). The first inlet (I1) is located near one end (rear end) in the third direction of the first plate space (81). Specifically, the first inlet (I1) is located at one end (rear end) in the third direction of the first plate space (81). One end of the first plate space (81) and the first inlet (I1) are continuous without any step.

[0092] The third front plate (FP3) has a first connecting hole (76) and a second connecting hole (77) formed as continuous channels with the diversion channel (70). The first connecting hole (76) is located in front of the outflow end of the first outflow channel (91). The second connecting hole (77) is located above the first connecting hole (76) and the first outflow channel (91). The first connecting hole (76) and the second connecting hole (77) are formed in a circular shape.

[0093] (4-2-2) Second front plate As shown in Figure 10, the second front plate (FP2) has an inlet passage (78), a second plate space (82), and a second outlet passage (92) formed as elements for constituting a flow diversion channel (70). The inlet passage (78), the second plate space (82), and the second outlet passage (92) are formed by holes that penetrate the second front plate (FP2) in the thickness direction (first direction).

[0094] The inlet passage (78) is part of the inflow passage (71). In this embodiment, the inlet passage (78) is curved in a U-shape. The outflow end of the inlet passage (78) overlaps with the inflow end of the inflow relay passage (75) in the first direction. The flow path cross-sectional area of ​​the inlet passage (78) is larger than the flow path cross-sectional area of ​​each of the outflow passages (91, 92, 93).

[0095] The second plate space (82) has a transversely elongated shape that extends in the third direction. In other words, the longitudinal direction of the second plate space (82) corresponds to the third direction. The second plate space (82) is formed in the shape of a rectangular parallelepiped.

[0096] The second outflow channel (92) has a vertically elongated shape extending in the second direction. The second inlet (I2), which is the inflow end of the second outflow channel (92), is continuous with the second plate space (82). The second inlet (I2) is located on the upper side of the second plate space (82). The second inlet (I2) is located near the other end (front end) in the third direction of the second plate space (82). Specifically, the second inlet (I2) is located at the other end (front end) in the third direction of the second plate space (82). The other end in the third direction of the second plate space (82) and the second inlet (I2) are continuous without any step.

[0097] The second front plate (FP2) has a first relay channel (94), a second relay channel (95), and a third relay channel (96) formed as continuous channels with the diversion channel (70). The first relay channel (94), the second relay channel (95), and the third relay channel (96) are formed by holes that penetrate the second front plate (FP2) in the thickness direction (first direction).

[0098] The first relay channel (94) connects to the first outflow channel (91) at the second front plate (FP2). The inlet end of the second relay channel (95) overlaps with the first communication hole (76) in the first direction. The second relay channel (95) communicates with the third outflow channel (93) via the first communication hole (76). The inlet end of the third relay channel (96) overlaps with the first outflow channel (91) in the first direction. The third relay channel (96) communicates with the first outflow channel (91).

[0099] (4-2-3) Fourth front plate As shown in Figure 11, the fourth front plate has a third plate space (83) and a third outflow channel (93) formed as elements for constituting a flow diversion channel (70). The third plate space (83) and the third outflow channel (93) are formed by holes that penetrate the fourth front plate (FP4) in the thickness direction (first direction).

[0100] The third plate space (83) has a transversely elongated shape that extends in the third direction. In other words, the longitudinal direction of the third plate space (83) corresponds to the third direction. The third plate space (83) is formed in the shape of a rectangular parallelepiped.

[0101] The third outflow channel (93) has a vertically elongated shape extending in the second direction. The third inlet (I3), which is the inflow end of the third outflow channel (93), is continuous with the third plate space (83). The third inlet (I3) is located on the upper side of the third plate space (83). The third inlet (I3) is located near the other end (front end) in the third direction of the third plate space (83). Specifically, the third inlet (I3) is located at the other end (front end) in the third direction of the third plate space (83). The other end in the third direction of the third plate space (83) and the third inlet (I3) are continuous without any step.

[0102] The fourth front plate (FP4) has a fourth relay channel (97), a fifth relay channel (98), and a sixth relay channel (99) formed in it as channels continuous with the diversion channel (70). The fourth relay channel (97), the fifth relay channel (98), and the sixth relay channel (99) are formed by holes that penetrate the fourth front plate (FP4) in the thickness direction (first direction).

[0103] The fourth relay channel (97) connects to the third outflow channel (93) at the fourth front plate (FP4). The inlet end of the fifth relay channel (98) overlaps with the second communication hole (77) in the first direction. The fifth relay channel (98) communicates with the second outflow channel (92) via the second communication hole (77). The inlet end of the sixth relay channel (99) overlaps with the first outflow channel (91) in the first direction. The sixth relay channel (99) communicates with the first outflow channel (91).

[0104] (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 constituted 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.

[0105] The flow diversion space (80) is formed in a rectangular parallelepiped shape. Assuming that 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.

[0106] 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 suppress the distance between the outlet (O) and each inlet (I1, I2, I3) and the outlet (O) 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).

[0107] (4-5) Positional relationship between the outlet and each inlet FIG. 12 is a cross-sectional view of the flow diversion space. The outlet (O) of the inflow path (71) 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). The outlet (O) and each inlet (I1, I2, I3) are arranged on opposite sides with the flow diversion space (80) interposed therebetween.

[0108] The cross-section of the outlet (O) is rectangular. The cross-section of the outlet (O) is elongated horizontally, extending in a third direction. In this way, by extending the outlet (O) along the surface and back surface of the plate (P) perpendicular to its flow direction, the flow path cross-sectional area of ​​the outlet (O) can be increased.

[0109] The outlet (O) is located in the middle of the first direction in the flow separation space (80). When viewed in the second direction, the outlet (O) is located at a position that coincides with the centerline of the flow separation space (80) in the first direction (first centerline (M1)). The outlet (O) is located in the middle of the third direction in the flow separation space (80). When viewed in the second direction, the outlet (O) is located at a position that coincides with the centerline of the flow separation space (80) in the third direction (second centerline (M2)). Thus, when viewed in the first direction, the outlet (O) is located in the center of the flow separation space (80).

[0110] The cross-section of each inlet (I1, I2, I3) is rectangular. The cross-section of each inlet (I1, I2, I3) is elongated horizontally, extending in the third direction. In this way, by extending the inlets (I1, I2, I3) along the surface and back surface of the plate (P) perpendicular to the flow direction, the flow path cross-sectional area of ​​the inlets (I1, I2, I3) can be increased. The first inlet (I1), the second inlet (I2), and the third inlet (I3) are arranged in a staggered pattern when viewed in the second direction.

[0111] The first inlet (I1) and outlet (O) are offset from each other when viewed in the second direction. The first inlet (I1) and outlet (O) are located in the middle of the first direction in the flow separation space (80). Specifically, the first inlet (I1) and outlet (O) are located on the first centerline (M1) when viewed in the second direction. The outlet (O) is located on the second centerline (M2) when viewed in the second direction. The first inlet (I1) is located at the other end (rear end) in the third direction. The first inlet (I1) is positioned flush with the rear surface (80c) that defines the flow separation space (80).

[0112] The second inlet (I2) and outlet (O) are offset from each other when viewed in the second direction. The second inlet (I2) is located at one end (left end) in the first direction of the flow separation space (80). The second inlet (I2) is located at one end (front end) in the third direction of the flow separation space (80). Thus, the second inlet (I2) is located at a corner of the flow separation space (80) when viewed in the second direction. By positioning the second inlet (I2) at a corner of the flow separation space (80), it is possible to prevent the distance between the outlet (O) and the second inlet (I2) from becoming too short. The second inlet (I2) is positioned flush with the left surface (80d) and the front surface (80e) that define the flow separation space (80).

[0113] The third inlet (I3) and outlet (O) are offset from each other when viewed in the second direction. The third inlet (I3) is located at the other end (right end) of the first direction in the flow separation space (80). The third inlet (I3) is located at one end (front end) of the third direction in the flow separation space (80). Thus, the third inlet (I3) is located at the corner of the flow separation space (80) when viewed in the second direction. By positioning the third inlet (I3) at the corner of the flow separation space (80), it is possible to prevent the distance between the outlet (O) and the third inlet (I3) from becoming too short. The third inlet (I3) is positioned flush with the right face (80f) and the front face (80e) that define the flow separation space (80).

[0114] (5) Operating The air conditioning system (10) performs cooling, heating, and dehumidifying operations.

[0115] (5-1) Cooling operation During cooling operation, the controller of the air conditioning unit (10) operates the compressor (21), outdoor fan (25), and indoor fan (32), sets the four-way switching valve (24) to the first state (shown by the solid line in Figure 1), adjusts the opening degree of the outdoor expansion valve (23) as appropriate, and fully opens the indoor expansion valve (37).

[0116] During 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.

[0117] The indoor unit (30) draws indoor air from the indoor space (5) into the air passage (38) via the intake port (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) from the outlet (34).

[0118] In the heat exchanger unit (U), the refrigerant flowing into the liquid transfer 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 room air as it passes through each heat transfer tube (42). Subsequently, the refrigerant flows through the front plate stack (50) into the first internal piping (71a), and then sequentially through the room expansion valve (37) and the second internal piping (71b) to flow 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 room air as it passes through each heat transfer tube (42). Subsequently, the refrigerant flows through the rear plate stack (60) into the gas transfer pipe (68) and flows out of the heat exchanger unit (U).

[0119] (5-2) Heating operation During heating operation, the controller of the air conditioning unit (10) operates the compressor (21), outdoor fan (25), and indoor fan (32), sets the four-way switching valve (24) to the second state (shown by the dashed line in Figure 1), adjusts the opening of the outdoor expansion valve (23) to a predetermined opening, and fully opens the indoor expansion valve (37).

[0120] During heating operation, the refrigerant circuit (11) performs a refrigeration cycle in which the indoor heat exchanger (40) functions as a condenser (radiator) and the outdoor heat exchanger (22) functions as an evaporator.

[0121] The indoor unit (30) draws indoor air from the indoor space (5) into the air passage (38) via the intake port (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) from the outlet (34).

[0122] In the heat exchanger unit (U), the refrigerant flowing 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 into the room air as it passes through each heat transfer tube (42). Subsequently, the refrigerant flows through the rear plate stack (60) into the second internal piping (71b), and then sequentially through the room expansion valve (37) and the first internal piping (71a) to flow into the front plate stack (50) of the front heat exchange section (40A). In the front heat exchange section (40A), the refrigerant dissipates heat into the room air as it passes through each heat transfer tube (42). Subsequently, the refrigerant flows through the front plate stack (50) into the liquid relay pipe (67) and out of the heat exchanger unit (U).

[0123] (5-3) Dehumidification operation During dehumidification operation, the controller of the air conditioning unit (10) operates the compressor (21), outdoor fan (25), and indoor fan (32), sets the four-way switching valve (24) to the first state (shown by the solid line in Figure 1), and adjusts the opening of the outdoor expansion valve (23) and indoor expansion valve (37) as appropriate.

[0124] 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 condensers (radiators), and the rear heat exchange section (40B) of the indoor heat exchanger (40) functions as an evaporator.

[0125] The indoor unit (30) draws indoor air from the indoor space (5) into the air passage (38) via the intake port (33). The rear heat exchange unit (40B) cools the air in the air passage (38) to below the dew point temperature. The front heat exchange unit (40A) heats the air in the air passage (38). The air that has passed through both heat exchange units mixes in the air passage (38), resulting in air with low humidity. This dehumidified air is then supplied to the indoor space (5) from the outlet (34).

[0126] In the heat exchanger unit (U), the refrigerant flowing into the liquid transfer 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 releases heat to the room air as it passes through each heat transfer tube (42). Subsequently, the refrigerant flows through the front plate stack (50) into the first internal piping (71a), is depressurized as it passes through the room expansion valve (37), flows through the second internal piping (71b), 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 room air as it passes through each heat transfer tube (42). Subsequently, the refrigerant flows through the rear plate stack (60) into the gas transfer pipe (68) and flows out of the heat exchanger unit (U).

[0127] (5-4) Flow in the branch channel When the air conditioning system (10) is in operation, the refrigerant inside the front plate stack (50) flows through the flow divider channel (70). An example of the refrigerant flow in the flow divider channel (70) is described below.

[0128] The refrigerant flowing through the inlet path (78) shown in Figure 8 flows through the narrowed section (75a) of the inlet relay path (75). In the narrowed section (75a), the flow velocity of the refrigerant increases. As a result, the flow velocity of the refrigerant flowing through the diversion space (80) increases, which improves the refrigerant diversion performance in the diversion space (80).

[0129] The refrigerant that has passed through the narrowing section (75a) flows out from the outlet (O) into the flow separation space (80). The refrigerant that has been separated into the flow separation space (80) is dispersed so as to be directed towards the first inlet (I1), the second inlet (I2), and the third inlet (I3).

[0130] If the outlet (O) and a certain inlet overlap when viewed from a second direction, the refrigerant is likely to flow unevenly towards that inlet. In contrast, in this embodiment, the outlet (O) and each inlet (I1, I2, I3) are offset from each other when viewed from a second direction. Therefore, it is possible to suppress the uneven flow of the refrigerant diverted from the outlet (O) towards some of the outlets (O).

[0131] In this embodiment, the distance between the outlet (O) and the first inlet (I1), the distance between the outlet (O) and the second inlet (I2), and the distance between the outlet (O) and the third inlet (I3) are close to each other. Therefore, it is possible to suppress the refrigerant diverted from the outlet (O) from flowing unevenly to some of the inlets (I1, I2, I3).

[0132] The refrigerant that flows into the first inlet (I1) of the third front plate (FP3) flows through the first outlet (91). The refrigerant in the first outlet (91) is further divided into the third intermediate flow path (96) of the second front plate (FP2) and the sixth intermediate flow path (99) of the fourth front plate (FP4).

[0133] The refrigerant that flows to the second inlet (I2) of the second front plate (FP2) flows through the second outlet (92). A portion of the refrigerant in the second outlet (92) flows through the first relay channel (94) of the second front plate (FP2). The remaining refrigerant passes through the second communication hole (77) of the third front plate (FP3) and then flows through the fifth relay channel (98) of the fourth front plate (FP4).

[0134] The refrigerant that has been diverted to the third inlet (I3) of the fourth front plate (FP4) flows through the third outlet passage (93). A portion of the refrigerant in the third outlet passage (93) flows through the fourth relay passage (97) of the fourth front plate (FP4). The remaining refrigerant passes through the first communication hole (76) of the third front plate (FP3) and then flows through the third relay passage (96) of the second front plate (FP2).

[0135] (6) Effects of the Embodiment (6-1) A flow diversion channel (70) for diverting the refrigerant is formed in the plate stack (50, 60). The flow diversion channel (70) includes an inlet (71) extending in a second direction along the vertical, a flow diversion space (80) to which the outlet (O) of the inlet (71) is connected, and inlets (I1, I2, I3) connected to the flow diversion space (80), as well as a plurality of outlets (91, 92, 93) extending in the second direction. The plurality of plates (P) each have plate spaces (81, 82, 83) formed and include a plurality of flow diversion plates (FP2, FP3, FP4) adjacent in the first direction. The flow diversion space (80) is formed by the continuity of each plate space (81, 82, 83) of the plurality of flow diversion plates (FP2, FP3, FP4) in the first direction.

[0136] Since the flow separation space (80) spans multiple flow separation plates (FP2, FP3, FP4), the volume of the flow separation space (80) can be increased compared to the case where the flow separation space (80) is formed on a single plate (P). This makes it easier to equalize the distance between the outlet (O) and each inlet (I1, I2, I3), thus suppressing the refrigerant from flowing unevenly to some of the inlets (I1, I2, I3). As a result, the flow separation performance of the flow separation channel (70) can be improved. This effect is particularly pronounced when there are three or more outlet passages (91, 92, 93).

[0137] In addition, by forming a flow-dividing space (80) with multiple plate spaces (81, 82, 83), the flow path cross-sectional area of ​​the flow-dividing space (80) can be increased. Therefore, by reducing the flow velocity of the refrigerant, the pressure loss of the refrigerant flowing through the flow-dividing space (80) can be reduced.

[0138] (6-2) The outlet (O) is located on the opposite side of the flow separation space (80) from the inlets (I1, I2, I3). Compared to the case where the outlet (O) and inlets (I1, I2, I3) are on the same side of the flow separation space (80), the overall flow resistance of the flow separation channel (70) can be reduced.

[0139] (6-3) The outlet (O) and each inlet (I1, I2, I3) are offset from each other when viewed from a second direction. Since the outlet (O) and a particular inlet (I1, I2, I3) do not overlap when viewed from a second direction, it is possible to suppress the refrigerant from flowing unevenly towards a particular inlet (I1, I2, I3).

[0140] (6-4) At least two of the multiple inlets (I1, I2, I3) are formed on different flow dividers (FP2, FP3, FP4). Specifically, at least three of the three inlets (I1, I2, I3) are formed on different flow dividers (FP2, FP3, FP4). In this example, all three inlets (I1, I2, I3) are formed on different flow dividers (FP2, FP3, FP4). This makes it easier to equalize the distance between the outlet (O) and each inlet (I1, I2, I3). Note that if the number of inlets is greater than the number of flow dividers (three or more), at least three inlets may be formed on different flow dividers, and two or more inlets may be formed on the same flow divider.

[0141] (6-5) The multiple flow dividers (FP2, FP3, FP4) include a third front plate (FP3) on which an outlet (O) is formed, a second front plate (FP2) positioned on one end of the third front plate (FP3) in the thickness direction on which a second inlet (I2) is formed, and a fourth front plate (FP4) positioned on the other end of the third front plate (FP3) in the thickness direction on which a third inlet (I3) is formed.

[0142] This configuration makes it easier to equalize the distance between the outlet (O) and the second inlet (I2), and the distance between the outlet (O) and the third inlet (I3). As a result, uneven flow of the refrigerant between the second outflow passage (92) and the third outflow passage (93) can be suppressed.

[0143] (6-6) The plate space (81, 82, 83), when viewed from the second direction, has a horizontally elongated shape that extends in a third direction perpendicular to the first direction and along the horizontal direction.

[0144] Therefore, the flow separation space (80) formed by the plate spaces (81, 82, 83) can be enlarged, making it easier to equalize the distance between the outlet (O) and each inlet (I1, I2, I3). The flow path cross-sectional area of ​​the flow separation space (80) can be increased. The pressure loss of the refrigerant in the flow separation space (80) can be reduced.

[0145] (6-7) The plate spaces (81, 82, 83) are holes that penetrate the flow divider plates (FP2, FP3, FP4) in the thickness direction. Therefore, the plate spaces (81, 82, 83) can be easily machined in plate (P). By making the plate spaces (81, 82, 83) holes, the plate spaces (81, 82, 83) can be extended to their maximum extent in the thickness direction.

[0146] Since the plate spaces (81, 82, 83) have the same shape as each other, processing of the plate spaces (81, 82, 83) becomes even easier. The volume of the flow separation space (80) can be maximized.

[0147] (6-8) The outlet (O) is located in the middle of the third direction of the flow separation space (80), while the second inlet (I2) and third inlet (I3) are located near the ends of the third direction of the flow separation space (80). This prevents the distance between the outlet (O) and the second inlet (I2), and the distance between the outlet (O) and the third inlet (I3), from becoming too short. As a result, uneven flow of refrigerant to the second inlet (I2) and third inlet (I3) can be suppressed.

[0148] (6-9) The inlet passage (71) has a narrowing section (75a) that reduces the flow path cross-section as it approaches the downstream side. This improves the refrigerant diversion performance in the diversion space (80).

[0149] (6-10) The number of outlet passages (91, 92, 93) is preferably between three and five. Even if there are three outlet passages (91, 92, 93), uneven flow of the refrigerant can be suppressed by expanding the flow separation space (80).

[0150] By limiting the number of outflow channels (91, 92, 93) to five or fewer, it is possible to suppress uneven distances between the outlet (O) and each inlet (I1, I2, I3). This also prevents the structure of the diversion channels (70) and plate stacks (50, 60) from becoming overly complex.

[0151] It is preferable that the number of outflow channels (91, 92, 93) be odd.

[0152] The length of the flow separation 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 resistance of the flow separation space (80) can be reduced. By setting L2 to 6 mm or less, it is possible to prevent the distance between the outlet (O) and each inlet (I1, I2, I3) from becoming too long.

[0153] (6-11) A first region (A1) is formed in the front plate stack (50) that does not overlap with the front heat exchange section (40A) in the first direction. The flow diversion channel (70) is formed in the first region (A1).

[0154] If the flow diversion channel (70) overlaps with the front heat exchange section (40A) in the first direction, it becomes difficult to secure a region (second region) in the front plate stack (50) that connects to the heat transfer tubes (42). In contrast, the first region (A1) does not overlap with the front heat exchange section (40A) in the first direction, so the second region can be sufficiently secured.

[0155] (7) Variant The above-described embodiment may also be modified as follows. The differences from the above-described embodiment will be explained below.

[0156] (7-1) Variation 1 In the modified example 1 shown in Figure 13, the outlet (O) and each inlet (I1, I2, I3) are located on the same side of the flow separation space (80). The outlet (O) and each inlet (I1, I2, I3) are formed on the lower surface (80a) that defines the flow separation space (80). The outlet (O) and each inlet (I1, I2, I3) may also be formed on the upper surface (80b) that defines the flow separation space (80).

[0157] (7-2) Modification 2 In the modified example 2 shown in Figure 14, multiple inlets are formed on the same single plate (P). In this example, the first inlet (I1) and the second inlet (I2) are formed on the second front plate (FP2), and the third inlet (I3) and the fourth inlet (I4) are formed on the fourth front plate (FP4). The fourth inlet (I4) constitutes the inlet of the fourth outflow channel. The first inlet (I1) is located near one end of the third direction in the diversion space (80), and the second inlet (I2) is located near the other end of the third direction in the diversion space (80). The third inlet (I3) is located near one end of the third direction in the diversion space (80), and the fourth inlet (I4) is located near the other end of the third direction in the diversion space (80).

[0158] (7-3) Modified example 3 In the modified example 3 shown in Figure 15, the first inlet (I1), the second inlet (I2), and the third inlet (I3) are located slightly closer to the middle of the third direction than to the end of the flow separation space (80).

[0159] (7-4) Modification 4 The modified front plate stack (50) shown in Figure 16, part of the 4th modified example, has, in order from the side closest 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 an outlet (O) and a first inlet (I1). The third front plate (FP3) has a second inlet (I2), and the fifth front plate (FP5) has a third inlet (I3). In other words, the second inlet (I2) and the third inlet (I3) are located slightly closer to the middle of the flow separation space (80) than to the first direction end. In modified example 4, a second inlet (I2) may be formed on the second front plate (FP2), and a third inlet (I3) may be formed on the sixth front plate (FP6).

[0160] (7-5) Variation 5 In the modified example 5 shown in Figure 17, plate spaces (81, 82, 83) are formed by grooves formed in the plate (P). In the second front plate (FP2), a second plate space (82) is formed that is recessed in the first direction (left direction in Figure 17) from the third front plate (FP3) side. In the fourth front plate (FP4), a second plate space (82) is formed that is recessed in the first direction (right direction in Figure 17) from the third front plate (FP3) side.

[0161] (8) Other embodiments In the embodiments described above, and in each of the modified examples, the following configurations may also be used.

[0162] In the diversion channel (70), the refrigerant may flow downward in the second direction through the inlet channel (71) and each outlet channel (91, 92, 93).

[0163] The outlet (O) and a portion of the inlet (I1, I2, I3) may overlap in the second direction.

[0164] In the plate stack (50, 60), a flow diversion channel (70) may be formed in a region that overlaps with the heat exchange section (40A) in the first direction.

[0165] The inflow passage (71) may also be configured in which the narrowing section (75a) is omitted.

[0166] The diversion channel (70) may have two or more inflow channels (71).

[0167] A flow diversion channel (70) may be formed in the rear plate stack (60).

[0168] The refrigeration cycle device (10) can be any device that performs a vapor compression type refrigeration cycle, and is not limited to an air conditioning device. The refrigeration cycle device may be a cooling device that cools the inside of a refrigerator or cold storage warehouse, a chiller device that cools or heats a heat transfer medium such as water, or a heat pump type water heater that heats water to produce hot water.

[0169] The air conditioning system (10) does not have to be a paired system; it may also be a multi-system system.

[0170] The indoor unit (30) may be ceiling-mounted or floor-standing.

[0171] The orientation in which the front heat exchange section (40A) and the rear heat exchange section (40B) are aligned is not limited to the front-to-back direction, but may also be, for example, in the up-and-down direction.

[0172] The valve connected to the intermediate piping (66) does not have to be an expansion valve; it may be a solenoid valve, check valve, three-way valve, four-way switching valve, shut-off valve, etc.

[0173] The heat exchanger unit (U) may be applied to the outdoor heat exchanger (22) of the outdoor unit (20).

[0174] The indoor heat exchanger (40) does not have to be of the fin and tube type; for example, it may be of the corrugated type, in which corrugated fins are arranged between adjacent heat transfer tubes.

[0175] The heat exchanger body (B) may not have a front heat exchange section (40A) and a rear heat exchange section (40B), but may have a configuration with only one heat exchange section. In this case, a plate stack is provided corresponding to the one heat exchange section. The flow diversion channel (70) is formed in this plate stack.

[0176] The heat transfer tubes (42) and fins (41) of the heat exchanger body (B) may be made of copper. In this case, it is preferable that the plate stacks (50, 60) and the refrigerant piping connected to the plate stacks (50, 60) be made of copper. The plate stacks (50, 60) and the refrigerant piping connected to the plate stacks (50, 60) may be made of stainless steel.

[0177] Although embodiments and modifications have been described above, it will be understood that a variety of changes in form and details are possible without departing from the spirit and scope of the claims. Elements of the above embodiments, modifications, and other embodiments may be combined or substituted as appropriate.

[0178] The designations "1st," "2nd," "3rd," etc., mentioned above are used to distinguish between the terms to which these designations are attached, and do not limit the number or order of those terms. [Industrial applicability]

[0179] As described above, this disclosure is useful for heat exchanger units, air conditioning indoor units, and refrigeration cycle systems. [Explanation of symbols]

[0180] 10. Air conditioning system (refrigeration cycle system) 11 Refrigerant Circuit 40A Heat Exchanger 41 Fins 42 Heat transfer tubes 50-plate stack 51 Refrigerant flow path 70 Diversion channel 71 Inflow channel 75a Reduced section 80 Diversion space 81, 82, 83 Plate Space 91 1st outflow channel 92 2nd outflow channel 93 Third outflow channel A1 1st area FP2 Second Front Plate (Second Plate, Flow Diversion Plate) FP3 Third front plate (first plate, flow divider plate) FP4 4th front plate (3rd plate, flow divider plate) I1 1st inlet I2 2nd inlet I3 3rd inlet O Outlet P Plate U Heat Exchanger Unit

Claims

1. A heat exchange section (40A) having fins (41) and heat transfer tubes (42), The device comprises 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) that communicates with the heat transfer tube (42), The plate stack (50) has a flow diversion channel (70) for diverting the refrigerant. The aforementioned diversion channel (70) is An inlet passage (71) extending in a second direction along the vertical direction, The outlet (O) of the aforementioned inflow passage (71) is connected to a flow separation space (80), Each of the inlets (I1, I2, I3) connected to the aforementioned flow separation space (80) is included, along with a plurality of outflow passages (91, 92, 93) extending in the second direction. The plurality of plates (P) each have plate spaces (81, 82, 83) formed and include a plurality of flow dividers (FP2, FP3, FP4) adjacent to each other in the first direction. The flow separation space (80) is formed by the fact that each plate space (81, 82, 83) of the plurality of flow separation plates (FP2, FP3, FP4) is continuous in the first direction. The outlet (O) of the inlet (71) and the inlets (I1, I2, I3) of the plurality of outlet passages (91, 92, 93) are connected to the same single flow separation space (80). At least two of the plurality of inlets (I1, I2, I3) are formed on different flow dividers (FP2, FP3, FP4), The inlets (I1, I2, I3) of the aforementioned outflow passages (91, 92, 93) are formed on the upper surface (80b) or lower surface (80a) that define the flow separation space (80). Heat exchanger unit.

2. The outlet (O) is located on the opposite side of the flow separation space (80) from the inlets (I1, I2, I3). The heat exchanger unit according to claim 1.

3. The outlet (O) and the inlets (I1, I2, I3) are offset from each other when viewed in the second direction. The heat exchanger unit according to claim 2.

4. The aforementioned multiple inlets (I1, I2, I3) are three or more in number. At least three of the multiple inlets (I1, I2, I3) are formed on different flow dividers (FP2, FP3, FP4). The heat exchanger unit according to claim 1.

5. Multiple current distribution plates (FP2, FP3, FP4) The first plate (FP3) in which the outlet (O) is formed, A second plate (FP2) is positioned on one end of the first plate (FP3) in the thickness direction, and the inlets (I1, I2, I3) are formed therein. The first plate (FP3) includes a third plate (FP4) which is positioned on the other end in the thickness direction of the first plate (FP3) and in which the inlets (I1, I2, I3) are formed. A heat exchanger unit according to any one of claims 1 to 3.

6. The plate space (81, 82, 83), when viewed in the second direction, has a horizontally elongated shape that extends in a third direction perpendicular to the first direction and along the horizontal direction. A heat exchanger unit according to any one of claims 1 to 3.

7. The plate spaces (81, 82, 83) are holes that penetrate the flow divider plates (FP2, FP3, FP4) in the thickness direction. A heat exchanger unit according to any one of claims 1 to 3.

8. The aforementioned plate spaces (81, 82, 83) have the same shape as each other. The heat exchanger unit according to claim 7.

9. The outlet (O) is located in the middle of the plate space (81, 82, 83) in the third direction. The inlets (I1, I2, I3) are located near the end of the plate space (81, 82, 83) in the third direction. The heat exchanger unit according to claim 6.

10. The inflow channel (71) has a narrowing section (75a) that reduces the cross-sectional area of ​​the flow path as it approaches the flow separation space (80). A heat exchanger unit according to any one of claims 1 to 3.

11. The aforementioned multiple outflow channels (91, 92, 93) number between three and five. A heat exchanger unit according to any one of claims 1 to 3.

12. The length of the flow separation space (80) in the second direction is 1 mm or more and 6 mm or less. A heat exchanger unit according to any one of claims 1 to 3.

13. The plate stack (50) has a first region (A1) formed in which the heat exchange portion (40A) does not overlap in the first direction. The aforementioned diversion channel (70) is formed in the first region (A1) A heat exchanger unit according to any one of claims 1 to 3.

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

15. The refrigerant circuit (11) to which the heat exchanger unit (U) according to any one of claims 1 to 3 is connected is provided. Refrigeration cycle device.

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