Heat exchanger, refrigeration cycle device, air conditioning indoor unit, and method for manufacturing heat exchanger

The heat exchanger's guide and engaging portions facilitate easy alignment and connection of heat transfer tubes, addressing positioning challenges in complex arrangements and ensuring a compact design.

JP7807676B2Active Publication Date: 2026-01-28DAIKIN INDUSTRIES LTD
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Patent Information

Application Number
JP2023169515
Authority / Receiving Office
JP · JP
Patent Type
Patents
Current Assignee / Owner
Filing Date
2023-09-29
Publication Date
2026-01-28
Estimated Expiration
2043-09-29

AI Technical Summary

Technical Problem

Existing heat exchangers for air conditioning units face difficulties in positioning heat transfer tubes and connecting portions due to complex arrangements, making it challenging to align the heat transfer tubes with the refrigerant distributor.

Method used

The heat exchanger incorporates guide and engaging portions that protrude beyond the heat transfer tubes or connecting portions, allowing for easy alignment and connection by engaging before assembly, ensuring accurate positioning without additional space requirements.

Benefits of technology

This design facilitates easy and accurate positioning of heat transfer tubes and connecting portions, enabling a compact and efficient heat exchanger configuration.

✦ Generated by Eureka AI based on patent content.

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Patent Text Reader

Abstract

To facilitate positioning of a heat transfer pipe and a connection part, in a heat exchanger which has a plate structure body containing the plurality of connection parts connected to the plurality of heat transfer pipes.SOLUTION: A heat exchanger includes: a heat exchange part (40A) which has a heat transfer pipe (42) and a tube plate (80) which a heat transfer pipe (42) penetrates; and a plate structure body (50) which has a connection part (53) to which the heat transfer pipe (42) is connected. At least one of the heat exchange part (40A) and the plate structure body (50) includes a guide part (71) extending toward the other side, and at least the other of the heat exchange part (40A) and the plate structure body (50) has an engagement part (81) which is engaged with the guide part (71). Between a right side surface (80a) of the tube plate (80) and a first left side surface (52c) of the plate structure body (50), the sum of the length of the guide part (71) and the length of the engagement part (81) is larger than the sum of the length of the connection part (53) and the length of the heat transfer pipe (42).SELECTED DRAWING: Figure 11
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Description

[Technical Field]

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

[0002] Patent Document 1 discloses a structure for connecting a plurality of heat transfer tubes to an absorption liquid distribution header of an air-cooled absorber. The absorption liquid distribution header includes an absorption liquid distribution plate having a plurality of heat transfer tube insertion holes, and the absorption liquid distribution plate has a plurality of protrusions on the inner peripheral surfaces of at least two predetermined heat transfer tube insertion holes as positioning means for the plurality of heat transfer tube insertion holes relative to the absorption liquid and refrigerant vapor inlet portions of the absorption heat transfer tubes.

[0003] Patent Document 2 discloses a heat exchanger for an air conditioning indoor unit. The heat exchanger includes a heat exchanger body having a refrigerant flow path and a refrigerant distributor that distributes and supplies the refrigerant to a plurality of predetermined flow path portions in the heat exchanger body, and the refrigerant distributor is composed of a plurality of plate-shaped members that are superimposed on each other, including a plate-shaped distribution member. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2004-108744 [Patent Document 2] Japanese Patent Application Laid-Open No. 2006-125652 Summary of the Invention [Problem to be solved by the invention]

[0005] When a positioning protrusion is formed on the inner surface of the heat transfer tube insertion hole as in Patent Document 1, positioning requires looking into the heat transfer tube insertion hole from the axial direction of the hole. In the case of a heat exchanger for an air conditioning indoor unit as in Patent Document 2, the heat transfer tubes are often arranged in a complex manner, and the connection part of the refrigerant distributor made of plates also has a complex arrangement. In this case, when positioning the connection part between the heat transfer tube and the refrigerant distributor, it is difficult to look into the connection part of the refrigerant distributor and simultaneously grasp the arrangement of the heat transfer tube. With a configuration like Patent Document 1, positioning is difficult when the heat transfer tubes are arranged in a complex manner.

[0006] An object of the present disclosure is to facilitate the positioning of heat transfer tubes and connecting portions in a heat exchanger having a plate structure including a plurality of connecting portions to be connected to a plurality of heat transfer tubes. [Means for solving the problem]

[0007] The first aspect is directed to a heat exchanger. The heat exchanger includes a heat exchange section (40A, 240A, 340A, 440A, 540A) having fins (41), a plurality of heat transfer tubes (42), and a tube plate (80) located at an end in a predetermined direction (D) that is the axial direction of the heat transfer tubes (42) and through which the heat transfer tubes (42) penetrate; a main body (52, 352) including a refrigerant flow path (51) communicating with the plurality of heat transfer tubes (42); and a plate structure (50, 250, 350, 450, 550) having a plurality of connection portions (53, 353) communicating with the heat exchange portion (40A, 240A, 340A, 440A, 540A) and to which the heat transfer tube (42) is connected, and at least one of the heat exchange portion (40A, 240A, 340A, 440A, 540A) and the plate structure (50, 250, 350, 450, 550) has a guide portion ( 71, 271, 371, 471, 571), and at least the other of the heat exchange section (40A, 240A, 340A, 440A, 540A) and the plate structure (50, 250, 350, 450, 550) has an engaging section (81, 281, 381, 481, 581) that engages with the guide section (71, 271, 371, 471, 571), and the tube sheet (80) Between a surface (80a) of the guide portion (71, 271, 371, 471, 571) on the plate structure (50, 250, 350, 450, 550) side and a predetermined surface (52c, 352c) that is a surface of the main body portion (52, 352) on the heat exchange portion (40A) side, the sum of the length of the guide portion (71, 271, 371, 471, 571) in the predetermined direction (D) and the length of the engaging portion (81, 281, 381, 481, 581) in the predetermined direction (D) is greater than the sum of the length of the connecting portion (53, 353) from the predetermined surface (52c, 352c) and the length of the heat transfer tube (42) from the tube plate (80).

[0008] In the first aspect, the guide portions (71, 271, 371, 471, 571) and the engaging portions (81, 281, 381, 481, 581) engage with each other before the heat transfer tube (42) and the connecting portion (53) are connected. Therefore, the guide portions (71, 271, 371, 471, 571) and the engaging portions (81, 281, 381, 481, 581) can determine the positions of the heat transfer tube (42) and the connecting portion (53). At least one of the guide portions (71, 271, 371, 471, 571) and the engaging portions (81, 281, 381, 481, 581) protrudes further than the heat transfer tube (42) or the connecting portion (53), so the positions of the guide portions (71, 271, 371, 471, 571) and the engaging portions (81, 281, 381, 481, 581) can be seen when viewed from the side. Since the positions of the guide portions (71, 271, 371, 471, 571) and the engaging portions (81, 281, 381, 481, 581) can be easily seen, it becomes easy to position the heat transfer tube (42) and the connecting portion (53).

[0009] In a second aspect, in the first aspect, the connection portion (53) is a connection pipe that protrudes from the predetermined surface (52c) toward the heat exchange portion (40A, 240A, 440A, 540A), the guide portion (71, 271) is a part of the heat transfer pipe (42) or a part of the connection portion (53), and the engagement portion (81, 281) is connected to the guide portion (71, 271) of the heat transfer pipe (42) or the connection portion (53). When the guide portion (71) is the connecting portion (53), the length of the guide portion (71) from the predetermined surface (52c) is greater than the length of the connecting portion (53) from the predetermined surface (52c). On the other hand, when the guide portion (271) is the heat transfer tube (42), the length of the guide portion (271) from the tube plate (80) is greater than the length of the heat transfer tube (42) from the tube plate (80).

[0010] In the second aspect, if the guide portions (71, 271) and the engaging portions (81, 281) are formed as part of the heat transfer tube (42) and the connecting portion (53), there is no influence of misalignment of the guide portions (71, 271) and the engaging portions (81, 281), thereby improving the accuracy of positioning the heat transfer tube (42) and the connecting portion (53). Furthermore, there is no need to provide additional space for the guide portions (71, 271) and the engaging portions (81, 281), thereby enabling the heat exchanger to have a compact configuration.

[0011] In a third aspect of the second aspect, when the guide portion (71) is the connecting portion (53), the length of the guide portion (71) from the predetermined surface (52c) is greater than the length of the connecting portion (53) from the predetermined surface (52c) by 2 mm or more, while when the guide portion (271) is the heat transfer tube (42), the length of the guide portion (271) from the tube plate (80) is greater than the length of the heat transfer tube (42) from the tube plate (80) by 2 mm or more.

[0012] In the third aspect, the guide portion (71, 271) has a sufficient insertion margin, and therefore the guide portion (71, 271) is less likely to wobble when engaged with the engaging portion (81, 281), making it easier to position the heat transfer tube (42) and the connecting portion (53).

[0013] In a fourth aspect, in the second or third aspect, the number of the guide portions (71, 271) is two or more, and the number of the engagement portions (81, 281) is the same as the number of the guide portions (71, 271).

[0014] In the fourth aspect, even if the guide portion (71, 271) is a circular pipe, the heat transfer pipe (42) and the connection portion (53) can be reliably positioned.

[0015] A fifth aspect is any one of the second to fourth aspects, wherein the guide portion (71) is a part of the connecting portion (53), the engaging portion (81) is a part of the heat transfer tube (42), the connecting portion (53) is inserted inside the heat transfer tube (42), the engaging portion (81) has a flared portion (81a) at a tip, the tip of the guide portion (71) has a drawn portion (71a), and the outer diameter of the drawn portion (71a) is smaller than the inner diameter of the flared portion (81a).

[0016] In the fifth aspect, the guide portion (71) can be easily inserted into the engagement portion (81), and therefore, the heat transfer tube (42) and the connection portion (53) can be easily positioned.

[0017] A sixth aspect is any one of the second to fourth aspects, wherein the guide portion (271) is a part of the heat transfer tube (42), the engaging portion (281) is a part of the connecting portion (53), the heat transfer tube (42) is inserted inside the connecting portion (53), the engaging portion (281) has a flared portion (281a) at its tip, the tip of the guide portion (271) has a drawn portion (271a), and the outer diameter of the drawn portion (271a) is smaller than the inner diameter of the flared portion (281a).

[0018] In the sixth aspect, the guide portion (271) can be easily inserted into the engagement portion (281), and therefore, the heat transfer tube (42) and the connection portion (53) can be easily positioned.

[0019] In a seventh aspect, in the first aspect, the guide portion is a pin (471, 571) provided on at least one of the heat exchange portion (440A, 540A) and the plate structure (450, 550), and the engagement portion is a hole (481, 581) provided on at least the other of the heat exchange portion (440A, 540A) and the plate structure (450, 550).

[0020] In the seventh aspect, the degree of freedom in the shapes of the guide portions (471, 571) and the engaging portions (481, 581) is improved, and therefore the guide portions (471, 571) can be shaped to easily engage with the engaging portions (481, 581). By shaping the guide portions (471, 571) so that they are clearly distinguishable from the heat transfer tube and the connecting portion when viewed from the side, the positions of the guide portions (471, 571) and the engaging portions (481, 581) can be easily identified when viewed from the side. This facilitates the positioning of the heat transfer tube (42) and the connecting portion (53).

[0021] In an eighth aspect, in the seventh aspect, the pins (471, 571) and the holes (481, 581) are provided at positions that do not overlap with the fins (41) when viewed in the axial direction of the heat transfer tube (42).

[0022] In the eighth aspect, when the pins (471, 571) are inserted into the holes (481, 581), there is no risk of the pins (471, 571) interfering with the fins (41), and therefore the pins (471, 571) can be made longer. The longer pins (471, 571) provide a sufficient insertion margin, which makes the pins (471, 571) less likely to wobble when inserted into the holes (481, 581), and facilitates positioning of the heat transfer tubes (42) and the connection portions (53).

[0023] In a ninth aspect, in the seventh or eighth aspect, the length of the pin (471, 571) is 1 mm or more longer than the sum of the length of the heat transfer tube (42) from the tube plate (80) and the length of the connection portion (53) from the predetermined surface (52c).

[0024] In the ninth aspect, the pins (471, 571) have sufficient insertion margins, so that the pins (471, 571) are less likely to wobble when inserted into the holes (481, 581), making it easier to position the heat transfer tube (42) and the connection portion (53).

[0025] A tenth aspect is any one of the seventh to ninth aspects, wherein the cross-sectional shape of the pin (471, 571) is polygonal, and the shape of the hole (481, 581) when viewed from the hole axis direction is polygonal similar to the cross-sectional shape of the pin (471, 571).

[0026] In the tenth aspect, when the heat exchange unit (440A, 540A) and the plate structure (450, 550) attempt to rotate relative to each other around the pin (471, 571), the corners of the pin (471, 571) come into contact with the inner circumferential surfaces of the holes (481, 581), thereby suppressing the relative rotation between the heat exchange unit (440A, 540A) and the plate structure (450, 550). This facilitates positioning of the heat transfer tube (42) and the connection portion (53).

[0027] An eleventh aspect is a refrigeration cycle apparatus including a refrigerant circuit (11) to which the heat exchanger according to any one of the first to tenth aspects is connected.

[0028] A twelfth aspect is an air conditioner indoor unit (30) including the heat exchanger according to any one of the first to tenth aspects and a casing (31) that houses the heat exchanger.

[0029] A thirteenth aspect is a method for manufacturing a heat exchanger. The heat exchanger includes a heat exchange section (40A, 240A, 340A, 440A, 540A) having fins (41), a plurality of heat transfer tubes (42), and a tube plate (80) located at an end in a predetermined direction (D) that is the axial direction of the heat transfer tubes (42) and through which the heat transfer tubes (42) penetrate; a plate (80) having a main body portion including a refrigerant flow path (51) communicating with the plurality of heat transfer tubes (42), and a plurality of connection portions (53, 353) communicating with the refrigerant flow path (51) and to which the heat transfer tubes (42) are connected. and a plate structure (50, 250, 350, 450, 550), wherein one of the heat exchange section (40A) and the plate structure (50, 250, 350, 450, 550) has a guide section (71, 271, 371, 471, 571) extending toward the other, and the other of the heat exchange section (40A, 240A, 340A, 440A, 540A) and the plate structure (50, 250, 350, 450, 550) has the guide section (71, 271, 371, 471, 571) extending toward the other. The tube sheet (80) has engaging portions (81, 281, 381, 481, 581) that engage with the plate structures (50, 250, 350, 450, 550) of the heat transfer tubes (42), and the sum of the length of the guide portions (71, 271, 371, 471, 571) in the predetermined direction (D) between a surface (80a) of the tube sheet (80) that faces the plate structure (50, 250, 350, 450, 550) and a predetermined surface (52c, 352c) that is a surface of the main body portion (52, 352) that faces the heat exchange portion (40A, 240A, 340A, 440A, 540A) is greater than the sum of the length of the heat transfer tubes (42) from the tube sheet (80) and the length of the connecting portions (53) from the predetermined surface (52c).The manufacturing method includes a first step of bringing the heat exchange portion (40A, 240A, 340A, 440A, 540A) and the plate structure (50, 250, 350, 450, 550) close to each other in the predetermined direction (D) to engage the guide portion (71, 271, 371, 471, 571) with the engagement portion (81, 281, 381, 481, 581); and a second step of bringing the heat exchange unit (40A, 240A, 340A, 440A, 540A) and the plate structure (50, 250, 350, 450, 550) closer to each other in the predetermined direction (D) while the heat exchange unit (71, 371, 471, 571) and the engagement portion (81, 281, 381, 481, 581) are engaged with each other, thereby connecting the heat transfer tube (42) and the connection portion (53, 353).

[0030] According to the thirteenth aspect, in the first step, the guide portions (71, 271, 371, 471, 571) engage with the engaging portions (81, 281, 381, 481, 581) before the heat transfer tube (42) and the connecting portion (53) are connected together after the heat transfer tube (42) and the connecting portion (53) are first positioned by the guide portions (71, 271, 371, 471, 571) and the engaging portions (81, 281, 381, 481, 581). This facilitates positioning of the heat transfer tube (42) and the connecting portion (53). [Brief explanation of the drawings]

[0031] [Figure 1] FIG. 1 is a piping diagram of an air conditioner having a heat exchanger according to the first embodiment. [Figure 2] FIG. 2 is a front view of the air conditioning indoor unit. [Figure 3] FIG. 3 is a cross-sectional view of the air conditioning indoor unit taken along line II-II. [Figure 4] FIG. 4 is a front view showing the internal structure of the air conditioning indoor unit. [Figure 5] FIG. 5 is a view of the heat exchange section as seen from the right side. [Figure 6] FIG. 6 is a plan view showing the heat exchange unit. [Figure 7]FIG. 7 shows the plate stack as seen from the left side. [Figure 8] FIG. 8 is a cross-sectional view illustrating a coolant flow path of the plate stack. [Figure 9] FIG. 9 is a view of the first plate stack as seen from the right side. [Figure 10] FIG. 10 is a view of the second plate stack as seen from the right side. [Figure 11] FIG. 11 is a view showing the process of connecting the front connection portion and the heat transfer tube, showing a state in which the guide portion and the engagement portion are separated from each other. [Figure 12] FIG. 12 is a diagram showing the process of connecting the front connection portion and the heat transfer tube, showing a state in which the guide portion and the engagement portion are engaged with each other. [Figure 13] FIG. 13 is a cross-sectional view showing a state in which the guide portion and the engagement portion are connected. [Figure 14] FIG. 14 is a view of the heat exchanger according to the second embodiment, which corresponds to FIG. [Figure 15] FIG. 15 is a cross-sectional view showing a connection state between a guide portion and an engagement portion in a heat exchanger according to the second embodiment. [Figure 16] FIG. 16 is a view of the heat exchanger according to the third embodiment, which corresponds to FIG. [Figure 17] FIG. 17 is a diagram showing guide pins and engagement holes in a heat exchanger according to the fourth embodiment. [Figure 18] FIG. 18 is a view of the first plate stack in the heat exchanger according to the fourth embodiment, viewed from the right side. [Figure 19] FIG. 19 is a view showing a process of connecting the front connection portion and the heat transfer tube in the heat exchanger according to the fourth embodiment, showing a state in which the guide pin and the engagement hole are engaged with each other. [Figure 20] FIG. 20 is a diagram showing a process of connecting the front connection portion and the heat transfer tube in the heat exchanger according to the fourth embodiment, showing the state in which the front connection portion and the heat transfer tube are connected. [Figure 21] FIG. 21 is a view of the periphery of the guide pin as viewed from the left side of the tube plate in a state in which the heat transfer tube and the connection portion are connected. [Figure 22]FIG. 22 is a view of the heat exchanger according to the fifth embodiment, which corresponds to FIG. DETAILED DESCRIPTION OF THE INVENTION

[0032] Hereinafter, 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 concept of the present disclosure. Since the drawings are intended to conceptually explain the present disclosure, dimensions, ratios, or numbers may be exaggerated or simplified as necessary to facilitate understanding.

[0033] First Embodiment (1) Overall configuration of the air conditioning unit The first embodiment is an air conditioner (10) including a heat exchanger unit. The air conditioner (10) adjusts the temperature of air in an indoor space (I) 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.

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

[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 type. The outdoor expansion valve (23) reduces the pressure of the refrigerant. The outdoor expansion valve (23) is an electronic expansion valve. The four-way selector valve (24) switches between a first state (a state indicated by a solid line in FIG. 1 ) and a second state (a state indicated by a dashed line in FIG. 1 ). In the first state, the four-way selector valve (24) connects the discharge port of the compressor (21) to the gas end of the outdoor heat exchanger (22) and connects the suction port of the compressor (21) to the first connecting pipe (12). The four-way selector valve (24) in the second state communicates the discharge port of the compressor (21) with the first connecting pipe (12) and also communicates the suction port 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), and an indoor heat exchanger (40), an indoor fan (32), and an indoor expansion valve (37) housed in the casing (31).

[0039] (2) Air conditioning indoor unit The indoor unit (30) serving as an indoor air conditioner will be described in detail with reference to Figures 2 to 4. The indoor unit (30) of the first embodiment is a wall-mounted type installed on a wall of the indoor space (I). In the following description, the terms "upper," "lower," "right," "left," "front," and "rear" correspond to the directions of the arrows shown in Figures 2 and 3, and the left-right direction is based on the case where the indoor casing (31) is viewed from the front.

[0040] (2-1) Casing 2 and 3, the casing (31) is formed in the shape of a horizontally long box and includes 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 air inlet (33) is formed in the upper plate (31c), and an air outlet (34) is formed in the lower plate (31d). An air passage (P) is formed inside the casing (31) from the air inlet (33) to the air outlet (34). The air inlet (33) extends in the longitudinal direction of the casing (31). The air inlet (33) is an opening for taking air from the indoor space (I) into the air passage (P). An air outlet (34) is formed in the lower plate (31d). The air outlet (34) extends in the longitudinal direction of the casing (31). The air outlet (34) is an opening for blowing air from the air passage (P) into the indoor space (I).

[0043] (2-2) Filter The indoor unit (30) includes a filter (35). The filter (35) is located at the back of the air inlet (33) and upstream of the indoor heat exchanger (40). The filter (35) collects dust in the air sent from the air inlet (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 exchanger unit The heat exchanger unit (U) includes one indoor heat exchanger (40) and one indoor expansion valve (37). The indoor heat exchanger (40) includes one heat exchanger body (B) and two plate stacks (50, 60). The heat exchanger body (B) of the indoor heat exchanger (40) is disposed so as to cross the air passage (P). The air passage (P) is divided into an upstream side and a downstream side of the heat exchanger body (B).

[0045] (2-4) Indoor fan The indoor fan (32) is disposed in the air passage (P). The indoor fan (32) is disposed in the air passage (P) downstream of the indoor heat exchanger (40). 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).

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

[0047] (3) Heat exchanger unit As described above, the heat exchanger unit (U) includes the indoor heat exchanger (40), the indoor expansion valve (37), the gas relay pipe (12a), and the liquid relay pipe (13a).

[0048] (3-1) Indoor heat exchanger The indoor heat exchanger (40) shown in Figures 3 to 6 includes a heat exchanger body (B) and a plate stack (50, 60) connected to the heat exchanger body (B). The indoor heat exchanger (40) is a fin-and-tube heat exchanger having fins (41) and heat transfer tubes (42). The indoor heat exchanger (40) exchanges heat between air and a refrigerant.

[0049] The heat exchanger body (B) has a plurality of fins (41) arranged in the longitudinal direction of the casing (31), a plurality of heat transfer tubes (42) extending in the arrangement direction of the fins (41), and a tube plate (80) located at the end of the heat transfer tubes (42) in a predetermined direction (D), which is the axial direction of the heat transfer tubes (42), and through which the heat transfer tubes (42) pass.

[0050] 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 with long 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 fins (41) are made of an aluminum alloy.

[0051] The heat transfer tubes (42) are straight tubes. The heat transfer tubes (42) are made of an aluminum alloy. Alternatively, the heat transfer tubes (42) may be made of a copper 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 each of the heat transfer tubes (42), i.e., a right end, protrudes to the right of the fins (41). One end of each of the heat transfer tubes is connected to the plate stack (50, 60). Of the other ends of the heat transfer tubes (42), i.e., left end portions, of two adjacent heat transfer tubes (42) are connected to each other by a U-shaped tube (48). The two adjacent heat transfer tubes (42) and the U-shaped tube (48) connecting them are formed seamlessly and integrally.

[0052] The indoor heat exchanger (40) of the first 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 of the casing (31), and the rear heat exchange section (40B) is located toward the rear of the casing (31). The front heat exchange section (40A) and the rear heat exchange section (40B) are aligned in a direction perpendicular to both the up-down direction and the axial direction of the heat transfer tube (42), i.e., in the front-rear direction, with the indoor fan (32) sandwiched between them.

[0053] 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).

[0054] The front main heat exchange section (43) is disposed in the front heat exchange section (40A) closer to the indoor fan (32). The front main heat exchange section (43) has a V-shaped outer shape when viewed in the longitudinal direction of the heat transfer tubes (42). The tip of the V faces forward.

[0055] The front main heat exchange section (43) is composed of a first front main heat exchange section (43a) extending obliquely upward toward the rear side and a second front main heat exchange section (43b) extending obliquely downward toward the rear side. The first front main heat exchange section (43a) is located at an upper part of the front main heat exchange section (43), and the second front main heat exchange section (43b) is located at a lower part of the front main heat exchange section (43). The lower ends of the first front main heat exchange section (43a), i.e., the lower short sides of the fins (41), are in contact with the long sides of the fins (41) of the second front main heat exchange section (43b) (strictly speaking, the upper end portions of the long sides of the fins (41)). The angle between the rear long side of the first front main heat exchange section (43a) and the upper long side (the side closer to the first front main heat exchange section (43a)) of the second front main heat exchange section (43b) is approximately 90° to 110°. The fins (41) constituting the first front main heat exchange section (43a) and the fins (41) constituting the second front main heat exchange section (43b) may be integrally formed or may be separate.

[0056] 5, the first front main heat exchange section (43a) is formed with three main heat transfer tube rows (42a to 42c). Each of the main heat transfer tube rows (42a to 42c) is formed with a plurality of heat transfer tubes (42) aligned in a line in the direction of the long sides of the fins (41) constituting the first front main heat exchange section (43a). In each of the main heat transfer tube rows (42a to 42c), the plurality of heat transfer tubes (42) are arranged at regular intervals. Of the main heat transfer tube rows (42a to 42c), the main heat transfer tube row along the front long side of the first front main heat exchange section (43a) is the first main heat transfer tube row (42a), the main heat transfer tube row along the rear long side of the first front main heat exchange section (43a) is the third main heat transfer tube row (42c), and the main heat transfer tube row located between the first main heat transfer tube row (42a) and the third main heat transfer tube row (42c) is the second main heat transfer tube row (42b).

[0057] The second front main heat exchange section (43b) is provided with three main heat transfer tube rows (42d to 42f). Each of the main heat transfer tube rows (42d to 42f) is formed of a plurality of heat transfer tubes (42) arranged in a row in the direction of the long sides of the fins (41) constituting the second front main heat exchange section (43b). In each of the main heat transfer tube rows (42d to 42f), the plurality of heat transfer tubes (42) are arranged at regular intervals. Of the main heat transfer tube rows (42d to 42f), the main heat transfer tube row along the lower long side of the second front main heat exchange section (43b) is the fourth main heat transfer tube row (42d), the main heat transfer tube row along the upper long side of the second front main heat exchange section (43b) is the sixth main heat transfer tube row (42f), and the main heat transfer tube row located between the fourth main heat transfer tube row (42d) and the sixth main heat transfer tube row (42f) is the fifth main heat transfer tube row (42e).

[0058] 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 long and short sides of the fins (41) of the first front main heat exchange section (43a). In the first auxiliary heat exchange section (44), the heat transfer tubes (42) form a first auxiliary heat transfer tube array (42i) extending along the long sides of the fins. The number of heat transfer tubes (42) included in the first auxiliary heat transfer tube array (42i) is smaller than the number of heat transfer tubes included in the first to third main heat transfer tube arrays (42a to 42c).

[0059] 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 short sides of the fins (41) of the second auxiliary heat exchange section (45) are shorter than the lengths of the long sides and short sides of the fins (41) of the second front main heat exchange section (43b). In the second auxiliary heat exchange section (45), the heat transfer tubes (42) form one second auxiliary heat transfer tube array (42j) along the long sides of the fins. The number of heat transfer tubes (42) included in the second auxiliary heat transfer tube array (42j) is smaller than the number of heat transfer tubes included in the fourth to sixth main heat transfer tube arrays (42d to 42f).

[0060] 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). Two heat transfer tube rows (42g, 42h) are formed in the rear main heat exchange section (46). Each heat transfer tube row (42g, 42h) is formed of a plurality of heat transfer tubes (42) aligned in a line in the direction of the long sides of the fins (41) constituting the rear main heat exchange section (46). In each heat transfer tube row (42g, 42h), the plurality of heat transfer tubes (42) are arranged at regular intervals. Of the heat transfer tube rows (42g, 42h), the heat transfer tube row in front of the rear main heat exchange section (46) is the seventh main heat transfer tube row (42g), and the heat transfer tube row in back of the rear main heat exchange section (46) is the eighth main heat transfer tube row (42h).

[0061] 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 sides and short sides of the fins (41) of the third auxiliary heat exchange section (47) are shorter than the lengths of the long sides and short sides of the fins (41) of the rear main heat exchange section (46). The number of rows and columns of the heat transfer tubes (42) of the third auxiliary heat exchange section (47) is fewer than the number of rows and columns of the heat transfer tubes (42) of the rear main heat exchange section (46). In the third auxiliary heat exchange section (47), the heat transfer tubes (42) form one third auxiliary heat transfer tube array (42k) along the long sides of the fins. The number of heat transfer tubes (42) included in the third auxiliary heat transfer tube array (42k) is fewer than the number of heat transfer tubes included in the seventh and eighth main heat transfer tube arrays (42g, 42h).

[0062] The tube plate (80) is disposed to the right of the rightmost fin (41). The tube plate (80) is a resin member shaped to cover the rightmost fin (41) from the right side. The tube plate (80) is attached to the front heat exchange section (40A) and the rear heat exchange section (40B) and maintains the relative positions of the front heat exchange section (40A) and the rear heat exchange section (40B). The right ends of the heat transfer tubes (42) penetrate the tube plate (80) and are located to the right of the right side surface (80a) of the tube plate (80). Note that a tube plate may also be provided to the left of the leftmost fin (41).

[0063] The plate stack (50, 60) is disposed to the right of the rightmost fin (41) and parallel to 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). The plate stacks (50, 60) have therein refrigerant flow paths (51, 61) that communicate with the heat transfer tubes (42). The front plate stack (50) and the rear plate stack (60) will be described in detail later.

[0064] (3-2) Indoor expansion valve, gas relay pipe, liquid relay pipe The indoor expansion valve (37) is an electronic expansion valve with a variable opening. As shown in FIG. 6 , the indoor expansion valve (37) is disposed on the right side of the plate stacks (50, 60). The indoor expansion valve (37) is connected to the front plate stack (50) via a first internal pipe (38) and to the rear plate stack (60) via a second internal pipe (39). The first internal pipe (38) and the second internal pipe (39) are examples of refrigerant pipes that connect the refrigerant flow path (51) of the front plate stack (50) and the refrigerant flow path (61) of the rear plate stack (60).

[0065] One end of the gas relay pipe (12a) is connected to the rear plate stack (60). The other end of the gas relay pipe (12a) is connected to the first connecting pipe (12) via a joint. One end of the liquid relay pipe (13a) is connected to the front plate stack (50). The other end of the liquid relay pipe (13a) is connected to the second connecting pipe (13) via a joint.

[0066] (4) Plate stack The plate stack (50, 60) will be described in detail with reference to FIGS.

[0067] (4-1) Front plate stack The front plate stack (50) includes a front main body portion (52) having a refrigerant flow path (51) therein, a plurality of front connection portions (53) that communicate with the refrigerant flow path (51) and to which a plurality of heat transfer tubes (42) of the front heat exchange portion (40A) are connected, a front relay portion (54) to which the first internal piping (38) is connected, and a liquid end portion (55) that communicates with the second connection piping (13) via a liquid relay pipe (13a).

[0068] (4-1-1) Front main body part As shown in FIG. 6 , 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). In the front plate stack (50), a first front plate (521), a second front plate (522), a third front plate (523), a fourth front plate (524), and a fifth front plate (525) are stacked in order from the side closest to the front heat exchange section (40A). The second front plate (522), the third front plate (523), and the fourth front plate (524) are intermediate plates sandwiched between the first front plate (521) and the fifth front plate (525). The five front plates are flat plate-like members having the same outer edge shape. Each front plate is made of the same material as the heat transfer tubes (42) and the front connection parts (53). In the first embodiment, each front plate is made of an aluminum alloy. The material of each front plate (521-525) is not limited to an aluminum alloy and may be, for example, a copper alloy or stainless steel. The first front plate (521) and the fifth front plate (525) have a thickness of, for example, 1.5 mm. The second front plate (522), the third front plate (523), and the fourth front plate (524) have a thickness of, for example, 3.0 mm. The front plates are joined to each other by furnace brazing. Note that the number of front plates is merely an example, and the number may be four or less, or six or more. Hereinafter, when there is no need to distinguish between the front plates, they will be simply referred to as front plates.

[0069] 7, the front main body portion (52) has a first overlapping portion (52a) overlapping with the first front main heat exchange portion (43a) when viewed in the axial direction of the heat transfer tubes (42). The front main body portion (52) has a second overlapping portion (52b) overlapping with the second front main heat exchange portion (43b) when viewed in the axial direction of the heat transfer tubes (42). The first overlapping portion (52a) and the second overlapping portion (52b) are integral with each other. More specifically, the first overlapping portion (52a) and the second overlapping portion (52b) are formed by stacking the same front plates.

[0070] The front main body portion (52) has a first left side surface (52c) which is a surface on the front heat exchanger portion (40A) side (here, the left side) in the axial direction of the heat transfer tube (42), a first right side surface (52d) which is a surface opposite to the first left side surface (52c) in the axial direction, and a first circumferential surface (52e) which is a circumferential surface extending across the first left side surface (52c) and the first right side surface (52d). The first left side surface (52c) is a surface of the first front plate (521) which faces the front heat exchanger portion (40A). The first right side surface (52d) is a surface of the fifth front plate (525) which faces opposite to the fourth front plate (524). The first circumferential surface (52e) is a surface formed by the side surfaces of the front plates (521, 522, 523, 523, 525). The first left side surface (52c) corresponds to a predetermined surface.

[0071] (4-1-2) Front connection part The front connection portion (53) is a circular pipe that protrudes from the first left side surface (52c) toward the front heat exchange portion (40A). The material of the front connection portion (53) is an aluminum alloy. The material of the front connection portion (53) is not limited to an aluminum alloy and may be, for example, a copper alloy or stainless steel. As shown in FIG. 9 , the plurality of front connection portions (53) are disposed in both the first overlapping portion (52a) and the second overlapping portion (52b) of the front main body portion (52).

[0072] The front connection portions (53) of the first overlapping portion (52a) are arranged corresponding to the first to third main heat transfer tube rows (42a to 42c) and the first auxiliary heat transfer tube row (42i). The first overlapping portion (52a) has three main front connection portion rows (53a to 53c) and one first auxiliary front connection portion row (53i). In each of the main front connection portion rows (53a to 53c), the front connection portions (53) are arranged at regular intervals. Of the main front connection portion rows (53a-53c), the first main front connection portion row (53a) is the foremost main front connection portion row, the third main front connection portion row (53c) is the rearmost main front connection portion row, and the third main front connection portion row (53c) is the main front connection portion row located between the first main front connection portion row (53a) and the third main front connection portion row (53c). The first auxiliary front connection portion row (53i) is located in front of the first main front connection portion row (53a). The front connection portions (53) of the first main front connection portion row (53a) are connected to the heat transfer tubes (42) of the first main heat transfer tube row (42a). The front connection parts (53) of the second main front connection part row (53b) are connected to the heat transfer tubes (42) of the second main heat transfer tube row (42b). The front connection parts (53) of the third main front connection part row (53c) are connected to the heat transfer tubes (42) of the third main heat transfer tube row (42c). The front connection parts (53) of the first auxiliary front connection part row (53i) are connected to the heat transfer tubes (42) of the first auxiliary heat transfer tube row (42i).

[0073] The front connection portions (53) of the second overlapping portion (52b) are arranged corresponding to the fourth to sixth main heat transfer tube rows (42d to 42f) and the second auxiliary heat transfer tube row (42j). The second overlapping portion (52b) has three main front connection portion rows (53d to 53f) and one second auxiliary front connection portion row (53j). In each of the main front connection portion rows (53d to 53f), the front connection portions (53) are arranged at regular intervals. Of the main front connection portion rows (53d to 53f), the lowest main front connection portion row is the fourth main front connection portion row (53d), the uppermost main front connection portion row is the sixth main front connection portion row (53f), and the main front connection portion row located between the fourth main front connection portion row (53d) and the sixth main front connection portion row (53f) is the fifth main front connection portion row (53e). The second auxiliary front connection portion row (53j) is located below the fourth main front connection portion row (53d). The front connection portions (53) of the fourth main front connection portion row (53d) are connected to the heat transfer tubes (42) of the fourth main heat transfer tube row (42d). The front connection parts (53) of the fifth main front connection part row (53e) are connected to the heat transfer tubes (42) of the fifth main heat transfer tube row (42e). The front connection parts (53) of the sixth main front connection part row (53f) are connected to the heat transfer tubes (42) of the sixth main heat transfer tube row (42f). The front connection parts (53) of the second auxiliary front connection part row (53j) are connected to the heat transfer tubes (42) of the second auxiliary heat transfer tube row (42j).

[0074] The front connection portions 53 of each main front connection portion row (53a to 53f) have different outer diameters from the front connection portions 53 of each sub-front connection portion row (53i, 53j). Specifically, the outer diameter of the front connection portions 53 of each main front connection portion row (53a to 53f) is, for example, 5 mm. The outer diameter of the front connection portions 53 of each sub-front connection portion row (53i, 53j) is, for example, 7 mm.

[0075] The first length (H1), which is the length from the first left side surface (52c) of the front connection portion (53), is set to a length that does not melt the brazing material connecting the plates due to heat generated when the front connection portion (53) and the heat transfer tube (42) are connected by brazing. The first length (H1) is, for example, 5 mm or more.

[0076] The thickness of the front connection portion 53 is equal to or thinner than the thickness of the first front plate 521. The thickness of the front connection portion 53 is, for example, 0.4 mm or more.

[0077] One end of the front connection portion (53) is inserted into the inside of the open end of the corresponding heat transfer tube (42) and joined to the corresponding heat transfer tube (42) by burner brazing. The other end of the front connection portion (53) is inserted into a through hole formed in the first front plate (521) and joined to the first front plate (521) by brazing. The front connection portion (53) and the first front plate (521) may be molded seamlessly as a single piece by, for example, casting or sintering metal powder using a 3D printer.

[0078] (4-1-3) Front relay section, liquid end As shown in FIG. 7 , the front relay portion (54) is a circular pipe. The front relay portion (54) is provided on the fifth front plate (525) and disposed on the first right side surface (52d) of the front main body portion (52). In the front plate stack (50), the first internal piping (38) is connected to the first right side surface (52d) of the front plate stack (50). The front relay portion (54) is located at the rear of the boundary between the first overlapping portion (52a) and the second overlapping portion (52b) of the fifth front plate (525). The amount of protrusion of the front relay portion (54) from the first right side surface (52d) is smaller than the amount of protrusion of the front connecting portion (53) from the first left side surface (52c). The front relay portion (54) is joined to the end of the front first internal piping (38) by brazing.

[0079] The liquid end portion (55) is a circular pipe. The liquid end portion (55) is provided on the fifth front plate (525) and disposed on the first right side surface (52d) of the front main body portion (52). The liquid end portion (55) is located in the second overlapping portion (52b) of the fifth front plate (525). The amount by which the liquid end portion (55) protrudes from the first right side surface (52d) is the same as the amount by which the front relay portion (54) protrudes from the first right side surface (52d). The liquid end portion (55) is joined to the end of the liquid relay pipe (13a) by brazing.

[0080] At the position of the liquid end portion 55, the refrigerant flow path 51 of the front plate assembly 50 extends straight in the stacking direction of the front plates without being connected to other refrigerant flow paths 51. The refrigerant flow path 51 at the position of the liquid end portion 55 communicates with the heat transfer tube 42 located lowest in the second auxiliary heat exchange section 45.

[0081] The front relay portion (54) and the liquid end portion (55) are molded seamlessly and integrally with the fifth front plate (525). More specifically, the front relay portion (54), the liquid end portion (55), and the fifth front plate (525) are configured from a single member. The front relay portion (54) and the liquid end portion (55) are molded integrally with the fifth front plate (525) by burring the fifth front plate (525). The front relay portion (54) and the liquid end portion (55) may also be molded integrally with the fifth front plate (525) by casting or sintering metal powder using a 3D printer.

[0082] (4-2) Rear plate laminate The rear plate stack (60) includes a rear main body portion (62) having a refrigerant flow path (61) therein, a plurality of rear connection portions (63) that communicate with the refrigerant flow path (61) and to which a plurality of heat transfer tubes (42) of the rear heat exchange portion (40B) are connected, a rear relay portion (64) to which the second internal piping (39) is connected, and a gas end portion (65) that communicates with the first connection piping (12) via the gas relay pipe (12a).

[0083] (4-2-1) Rear body The rear body portion (62) has basically the same configuration as the front body portion (52), except for the shape of the outer edges of the plates as viewed in the axial direction of the heat transfer tubes (42) and the internal refrigerant flow paths (61). As shown in FIG. 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). In the rear plate stack (60), a first rear plate (621), a second rear plate (622), a third rear plate (623), a fourth rear plate (624), and a fifth rear plate (625) are stacked in order from the side closest to the rear heat exchange section (40B). The second rear plate (622), the third rear plate (623), and the fourth rear plate (624) are intermediate plates sandwiched between the first rear plate (621) and the fifth rear plate (625). The rear plates are made of the same material as the heat transfer tubes (42) and the rear connection portion (63). In the first embodiment, the rear plates are made of an aluminum alloy. The material of each of the rear plates (621-625) is not limited to an aluminum alloy and may be, for example, a copper alloy or stainless steel. The first rear plate (621) and the fifth rear plate (625) have a thickness of, for example, 1.5 mm. The second rear plate (622), the third rear plate (623), and the fourth rear plate (624) have a thickness of, for example, 3.0 mm. The five rear plates are joined to each other by furnace brazing. The number of rear plates is an example, and the number of rear plates may be four or less, or six or more. The number of front plates and the number of rear plates may be different. Hereinafter, when there is no need to distinguish between the respective rear plates, they will simply be referred to as rear plates.

[0084] The rear main body portion (62) has a second left side surface (62a) that is a surface facing the rear heat exchange unit (40B) in the axial direction of the heat transfer tube (42), a second right side surface (62b) that is a surface opposite the second left side surface (62a) in the axial direction, and a second circumferential surface (62c) that is a circumferential surface extending between the second left side surface (62a) and the second right side surface (62b). The second left side surface (62a) is a surface of the first rear plate (621) that faces the rear heat exchange unit (40B). The second left side surface (62a) is a surface of the fifth rear plate (625) that is opposite the fourth rear plate (624). The second circumferential surface (62c) is a surface formed by the side surfaces of the rear plates (621, 622, 623, 624, 625).

[0085] (4-2-2) Rear connection part The rear connection part (63) is a circular pipe that protrudes from the second left side surface (62a) toward the rear heat exchange part (40B). The rear connection part (63) is made of an aluminum alloy. The material of the rear connection part (63) is not limited to an aluminum alloy and may be, for example, a copper alloy or stainless steel.

[0086] As shown in FIG. 10 , the rear connection portions (63) are arranged corresponding to the seventh and eighth main heat transfer tube rows (42g, 42h) and the third auxiliary heat transfer tube row (42k). The rear plate stack (60) has two main rear connection portion rows (63a, 63b) and one first auxiliary rear connection portion row (63c). In each of the three main rear connection portion rows (63a, 63b), the rear connection portions (63) are arranged at regular intervals. Of the main rear connection portion rows (63a, 63b), the one located on the front side is the first main rear connection portion row (63a), and the one located on the rear side is the second main rear connection portion row (63b). The first auxiliary rear connection portion row (63c) is located rearward of the second main rear connection portion row (63b). The rear connection portions of the first main rear connection portion row (63a) are connected to the heat transfer tubes (42) of the seventh main heat transfer tube row (42g). The rear connection portions of the second main rear connection portion row (63b) are connected to the heat transfer tubes (42) of the eighth main heat transfer tube row (42h). The rear connection portions of the first sub-rear connection portion row (63c) are connected to the heat transfer tubes (42) of the third sub-heat transfer tube row (42k).

[0087] The length of the rear connection portion (63) from the second left side surface (62a) is, for example, 5 mm or more.

[0088] The thickness of the rear connecting portion 63 is equal to or thinner than the thickness of the first rear plate 621. The thickness of the rear connecting portion 63 is, for example, 0.4 mm or more.

[0089] One end of the rear connection portion (63) is inserted into the inside of the open end of the corresponding heat transfer tube (42) and joined to the corresponding heat transfer tube (42) by burner brazing. The other end of the rear connection portion (63) is inserted into a through hole formed in the first rear plate (621) and joined to the first rear plate (621) by brazing. The rear connection portion (63) and the first rear plate (621) may be molded seamlessly as a single piece by, for example, casting or sintering metal powder using a 3D printer.

[0090] (4-2-3) Rear relay section, gas end The rear relay portion (64) is a circular pipe. As shown in FIG. 7 , the rear relay portion (64) is provided on the fifth rear plate (625) and disposed on the second right side surface (62b) of the rear main body portion (62). That is, in the rear plate stack (60), the second internal pipe (39) connecting the refrigerant flow path (51) of the front plate stack (50) and the refrigerant flow path (61) of the rear plate stack (60) is connected to the second right side surface (62b) of the rear plate stack (60). The amount of protrusion of the rear relay portion (64) from the second right side surface (62b) is smaller than the amount of protrusion of the rear connection portion (63) from the second left side surface (62a). The rear relay portion (64) is joined to an end of the second internal pipe (39) by brazing.

[0091] The gas end portion (65) is a circular pipe. The gas end portion (65) is provided on the fifth rear plate (625) and disposed on the second right side surface (62b) of the rear main body portion (62). The amount of protrusion of the gas end portion (65) from the second right side surface (62b) is the same as the amount of protrusion of the rear relay portion (64) from the second right side surface (62b). The gas end portion (65) is joined to the end of the gas relay pipe (12a) by brazing.

[0092] The rear relay portion (64) and the gas end portion (65) are molded seamlessly and integrally with the fifth rear plate (625). More specifically, the rear relay portion (64), the gas end portion (65), and the fifth rear plate (625) are configured as a single member. The rear relay portion (64) and the gas end portion (65) are molded integrally with the fifth rear plate (625) by burring the fifth rear plate (625). The rear relay portion (64) and the gas end portion (65) may also be molded integrally with the fifth rear plate (625) by casting or sintering metal powder using a 3D printer.

[0093] (5) Guide portion, engagement portion As shown in FIGS. 11 to 13, the indoor heat exchanger (40) has a guide portion (71) and an engaging portion (81) that engages with the guide portion (71). The guide portion (71) and the engaging portion (81) are portions that position the heat transfer tube (42), the front connecting portion (53), and the rear connecting portion (63) when connecting the heat transfer tube (42) to the front connecting portion (53) and when connecting the heat transfer tube (42) to the rear connecting portion (63). The guide portion (71) is made up of a part of the front connecting portion (53) and a part of the rear connecting portion (63). The engaging portion (81) is made up of a part of the heat transfer tube (42).

[0094] (5-1) Guide section The guide portion (71) is a specific front connection portion that protrudes further toward the front heat exchange portion (40A) (left side) than the other front connection portions (53). A first specific length (HX1), which is the length of the guide portion (71) from the first left side surface (52c), is greater than the first length (H1) of the other connection portions (53). Specifically, the first specific length (HX1) is greater than the first length (H1) by 2 mm or more. The difference between the first specific length (HX1) and the first length (H1) is, for example, 2 mm to 35 mm.

[0095] As shown in FIGS. 11 and 12, three guide portions 71 are provided. The guide portions 71 are divided into a first overlapping portion 52a and a second overlapping portion 52b. One guide portion 71 is provided in the third main front connection portion row 53c, and two guide portions 71 are provided in the sixth main front connection portion row 53f. Note that guide portions 71 may be provided in the first main front connection portion row 53a and the fourth main front connection portion row 53d instead of or in addition to the third main front connection portion row 53c and the sixth main front connection portion row 53f. In this case, it is preferable to provide one or more guide portions 71 in the first main front connection portion row 53a and one or more guide portions 71 in the fourth main front connection portion row 53d. The guide portions (71) are not provided in the second main front connection portion row (53b) and the fifth main front connection portion row (53e).

[0096] The tip of the guide portion (71) is inserted into the heat transfer tube (42) serving as the engagement portion (81). The tip of the guide portion (71) has a drawn portion (71a) formed by drawing. As shown in Fig. 13, the tip of the drawn portion (71a) has a tapered shape in which the inner diameter increases toward the tip.

[0097] 10, the rear plate stack (60) also has guide portions (72). The configuration of the guide portions (72) provided in the rear plate stack (60) is the same as the guide portions (71) of the front plate stack (50) described above, and therefore detailed description thereof will be omitted. The guide portions (72) of the rear plate stack (60) are provided in the first main rear connection portion row (63a). The guide portions (72) of the rear plate stack (60) are not provided in the second main rear connection portion row (63b).

[0098] (5-2) Engagement part The engaging portion 81 is a heat transfer tube 42 to which the guide portion 72 is connected. A second specific length HX2, which is the length of the engaging portion 81 from the right side surface 80a of the tube plate 80, is the same as a second length H2, which is the length of the other heat transfer tube 42 from the right side surface 80a of the tube plate 80. Therefore, between the right side surface 80a of the tube plate 80 and the first left side surface 52c of the front plate stack 50, the sum of the length HX1 of the guide portion 71 in the predetermined direction D and the length HX2 of the engaging portion 81 in the predetermined direction D is greater than the sum of the length H2 of the heat transfer tube 42 from the right side surface 80a and the length H1 of the front connecting portion 53 from the first left side surface 52c.

[0099] The number of engaging portions (81) provided is the same as the number of guide portions (71). As shown in FIGS. 11 and 12, three engaging portions (81) are provided corresponding to the number of guide portions (71). The engaging portions (81) are provided separately for the first front main heat exchange portion (43a) and the second front main heat exchange portion (43b). One engaging portion (81) is provided for the third main heat transfer tube array (42c) and two engaging portions (81) are provided for the sixth main heat transfer tube array (42f). When the guide portions (71) are provided for the first main front connection portion array (53a) and the fourth main front connection portion array (53d), the engaging portions (81) are provided for the first main heat transfer tube array (42a) and the fourth main heat transfer tube array (42d). The engaging portion (81) is not provided in the second main heat transfer tube array (42b) and the fifth main heat transfer tube array (42e).

[0100] The heat transfer tube 42 that becomes the engaging portion 81 is provided with a marking to indicate that it is the engaging portion 81. The marking is achieved by changing the color of the right end of the heat transfer tube 42 or by providing a mark on the right end of the heat transfer tube 42. The marking is provided on the outer surface of the heat transfer tube 42 so that it can be seen by an operator from outside.

[0101] As shown in FIG. 13 , the tip of the engaging portion (81) is flared. The engaging portion (81) is doubly flared. The engaging portion (81) has a first flared portion (81a) and a second flared portion (81b) that is located closer to the tip of the first flared portion (81a) and has a larger diameter than the first flared portion (81a). The first flared portion (81a) is located on the left side of the tube plate (80). The second flared portion (81b) is located on the right side of the tube plate (80). The inner diameter of the first flared portion (81a) is larger than the outer diameter of the narrowed portion (71a) of the guide portion (71) and is smaller than the outer diameter of the portion of the guide portion (71) other than the narrowed portion (71a). The inner diameter of the second flared portion (81b) is larger than the outer diameter of the portion of the guide portion (71) other than the narrowed portion (71a). The first flare portion (81a) is located at the narrowed portion (71a) of the guide portion (71). The second flare portion (81b) is located at the portion of the guide portion (71) other than the narrowed portion (71a). When the outer diameter of the narrowed portion (71a) of the guide portion (71) is equal to or smaller than the inner diameter of the heat transfer tube (42), the first flare portion (81a) may be omitted, and only the second flare portion (81b) may be provided.

[0102] The rear heat exchange section (40B) also has an engagement portion. The configuration of the engagement portion provided in the rear heat exchange section (40B) is the same as the above-described engagement portion (81), and therefore detailed description thereof will be omitted. The engagement portion of the rear heat exchange section (40B) is provided in the seventh main heat transfer tube row (42g). The engagement portion of the rear heat exchange section (40B) is not provided in the eighth main heat transfer tube row (42h).

[0103] (6) Assembling the heat exchanger and plate stack The assembly of the heat exchange section and the plate stack will be described by taking as an example the assembly of the front heat exchange section (40A) and the front plate stack (50).

[0104] First, as shown in Fig. 11, the front heat exchange section (40A) and the front plate stack (50) are arranged so that the front heat exchange section (40A) is on the lower side and the front plate stack (50) is on the upper side. The front heat exchange section (40A) is arranged so that the third main heat transfer tube array (42c) and the sixth main heat transfer tube array (42f) are located on the front side as seen by an operator. The front plate stack (50) is arranged so that the third main front connection portion array (53c) and the sixth main front connection portion array (53f) are located on the front side as seen by an operator so that the guide portions (71) can be seen.

[0105] 12, the front heat exchange section (40A) and the front plate stack (50) are moved toward each other in a predetermined direction (D) to engage the engaging portions (81) with the guide portions (71). At this time, the heat transfer tubes (42) and the front connecting portions (53) other than the engaging portions (81) and the guide portions (71) are not yet engaged.

[0106] Next, with the engaging portions 81 and the guide portions 71 still engaged, the front heat exchange portion 40A and the front plate stack 50 are moved closer to each other in a predetermined direction D to engage the heat transfer tubes 42 with the front connecting portions 53. Since the positioning of the heat transfer tubes 42 and the front connecting portions 53 has been completed by the engaging portions 81 and the guide portions 71, the heat transfer tubes 42 can be easily engaged with the front connecting portions 53.

[0107] After the heat transfer tube 42 and the front connecting portion 53 are engaged with each other, the heat transfer tube 42 and the front connecting portion 53 are connected to each other by burner brazing. At this time, the engaging portion 81 and the guide portion 71 are also connected to each other by burner brazing.

[0108] (7) Driving behavior The air conditioner (10) performs cooling operation, heating operation, and dehumidifying operation.

[0109] (7-1) 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 of the outdoor expansion valve (23), and fully opens the indoor expansion valve (37).

[0110] During 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 (I) into the air passage (P) through the inlet (33). The air in the air passage (P) is cooled by the indoor heat exchanger (40). The cooled air is supplied to the indoor space (I) through the outlet (34).

[0112] (7-2) 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 indicated by the dashed line in FIG. 1 ), adjusts the opening of the outdoor expansion valve (23) to a predetermined opening, and fully opens the indoor expansion valve (37).

[0113] During 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.

[0114] The indoor unit (30) draws indoor air from the indoor space (I) into the air passage (P) through the inlet (33). The air in the air passage (P) is heated by the indoor heat exchanger (40). The heated air is supplied to the indoor space (I) through the outlet (34).

[0115] (7-3) Dehumidification operation In the dehumidifying 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 Figure 1), and appropriately adjusts the openings of the outdoor expansion valve (23) and the indoor expansion valve (37).

[0116] During the dehumidifying 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.

[0117] The indoor unit (30) draws room air from the indoor space (I) into the air passage (P) through the air inlet (33). The rear heat exchanger (40B) cools the air in the air passage (P) to a temperature below the dew point. The front heat exchanger (40A) heats the air in the air passage (P). The air passing through both the rear heat exchanger and the front heat exchanger mixes in the air passage (P) to become low-humidity air. The dehumidified air is supplied to the indoor space (I) through the air outlet (34).

[0118] (8) Effects of the First Embodiment In the first embodiment, the front plate stack (50) has a guide portion (71) extending toward the front heat exchange portion (40A), and the front heat exchange portion (40A) has an engaging portion (81) that engages with the guide portion (71). Between the right side surface (80a) of the tube plate (80) and the first left side surface (52c) of the front main body portion (52), the sum of the length (HX1) of the guide portion (71) in the predetermined direction (D) and the length (HX2) of the engaging portion (81) in the predetermined direction (D) is greater than the sum of the length (H1) of the front connection portion (53) from the first left side surface (52c) and the length (H2) of the heat transfer tube (42) from the tube plate (80). Because the guide portion (71) and the engaging portion (81) engage with each other before the heat transfer tube (42) and the connecting portion (53) are connected, the guide portion (71) and the engaging portion (81) can determine the position of the heat transfer tube (42) and the front connecting portion (53). At least one of the guide portion (71) and the engaging portion (81) protrudes further than the heat transfer tube (42) or the front connecting portion (53), so the positions of the guide portion (71) and the engaging portion (81) can be seen from the side. Because the positions of the guide portion (71) and the engaging portion (81) can be easily seen, the positioning of the heat transfer tube (42) and the front connecting portion (53) can be easily determined.

[0119] In the first embodiment, the front connection portion (53) is a connecting pipe that protrudes from the first left side surface (52c) toward the front heat exchange portion (40A), the guide portion (71) is a part of the front connection portion (53), the engagement portion (81) is a portion of the heat transfer tube (42) that is connected to the guide portion (71), and the length of the guide portion (71) from the first left side surface (52c) is greater than the length of the front connection portion (53) from the first left side surface (52c). Since there is no influence of misalignment of the guide portion (71) and the engagement portion (81), the accuracy of positioning of the heat transfer tube (42) and the connection portion (53) can be improved. Furthermore, there is no need to provide additional space for the guide portion (71) and the engagement portion (81), allowing the indoor heat exchanger (40) to have a compact configuration.

[0120] In particular, in the first embodiment, the length of the guide portion (71) from the first left side surface (52c) is greater by 2 mm or more than the length of the front connecting portion (53) from the first left side surface (52c). Because the guide portion (71) has a sufficient insertion margin, the guide portion (71) is less likely to wobble when engaged with the engaging portion (81), and this makes it easier to position the heat transfer tube (42) and the connecting portion (53).

[0121] In the first embodiment, the number of guide portions 71 is two or more, and the number of engagement portions 81 is the same as the number of guide portions 71. If the number of guide portions 71 is two or more, even if the guide portions 71 are circular pipes, it is possible to prevent the front plate assembly 50 from rotating around the guide portions 71. This ensures that the heat transfer tubes 42 and the connection portions 53 are positioned reliably.

[0122] In the first embodiment, the front connecting portion (53) is inserted into the heat transfer tube (42), the engaging portion (81) has a flared portion (81a) at its tip, and the guide portion (71) has a drawn portion (71a) at its tip, the outer diameter of the drawn portion (71a) being smaller than the inner diameter of the flared portion (81a). Since the guide portion (71) can be easily inserted into the engaging portion (81), the heat transfer tube (42) and the connecting portion (53) can be easily positioned.

[0123] In the first embodiment, the guide portion (71) is provided in the rearmost or frontmost main front connection portion row (53a, 53c, 53d, 53f), and the engagement portion (81) is provided in the rearmost or frontmost main heat transfer tube row (42a, 42c, 42d, 42f). When connecting the front connection portion (53) and the heat transfer tube (42), the worker can easily view the guide portion (71) and the engagement portion (81), which makes it easier to position the heat transfer tube (42) and the connection portion (53).

[0124] In the first embodiment, the guide portion (71) provided in the first overlapping portion (52a) is located closer to the second overlapping portion (52b), and the guide portion (71) provided in the second overlapping portion (52b) is located closer to the first overlapping portion (52a). Since the guide portions (71) are located close to each other, the worker can easily view the guide portions (71), which makes it easier to position the heat transfer tube (42) and the front connection portion (53).

[0125] In the first embodiment, the rear plate stack (60) also has a guide portion (72) like the front plate stack (50), and the rear heat exchange portion (40B) also has an engagement portion like the front heat exchange portion (40A). When connecting the heat transfer tubes (42) to the rear connection portions (63), the guide portion (72) and the engagement portion can determine the positions of the heat transfer tubes (42) and the rear connection portions (63).

[0126] Second Embodiment The embodiments of the present disclosure will be described in detail with reference to the drawings. In the following description, parts common to the first embodiment will be denoted by the same reference numerals, and detailed description thereof will be omitted.

[0127] (9) Guide portion, engagement portion 14 and 15, in the second embodiment, the guide portion (271) is formed by a part of the heat transfer tube (42). The engagement portion (281) is formed by a part of the front connection portion (53) and a part of the rear connection portion (63).

[0128] (9-1) Guide section The guide portion (271) is a specific heat transfer tube that protrudes further toward the front plate stack (250) (right side) than the other heat transfer tubes (42). A third specific length (HX3), which is the length of the guide portion (271) from the right side surface (80a) of the tube plate (80), is longer than the second length (H2) of the other heat transfer tubes (42). Specifically, the third specific length (HX3) is longer than the second length (H2) by 2 mm or more. The difference between the third specific length (HX3) and the second length (H2) is, for example, 2 mm to 25 mm.

[0129] As shown in FIG. 14 , three guide portions (271) are provided. The guide portions (271) are provided separately in the first front main heat exchange portion (43a) and the second front main heat exchange portion (43b). One guide portion (271) is provided in the third main heat transfer tube array (42c) and two guide portions (271) are provided in the sixth main heat transfer tube array (42f). Note that the guide portions (271) may be provided in the first main heat transfer tube array (42a) and the fourth main heat transfer tube array (42d) instead of or in addition to the third main heat transfer tube array (42c) and the sixth main heat transfer tube array (42f). The guide portions (271) are not provided in the second main heat transfer tube array (42b) and the fifth main heat transfer tube array (42e).

[0130] The tip of the guide portion (271) is inserted into the inside of the front connecting portion (53) serving as the engagement portion (281). The tip of the guide portion (271) has a drawn portion (271a) formed by drawing. The outer diameter of the drawn portion (271a) is smaller than the inner diameter of the front connecting portion (53). As shown in FIG. 15 , the tip of the drawn portion (271a) has a tapered shape in which the inner diameter increases toward the tip.

[0131] The rear main heat exchange section is also provided with a guide portion. The configuration of the guide portion provided in the rear heat exchange section is the same as that of the guide portion in the front heat exchange section (240A) described above, and therefore a detailed description thereof will be omitted. The guide portion of the rear heat exchange section is provided in the seventh main heat transfer tube row (42g). The guide portion of the rear heat exchange section is not provided in the eighth main heat transfer tube row (42h).

[0132] (9-2) Engagement part The engaging portion (281) is a front connecting portion (53) to which the guide portion (271) is connected. A fourth specific length (HX4) of the engaging portion (281) from the first left side surface (52c) is the same as a first length (H1) of the other front connecting portion (53) from the first left side surface (52c). Therefore, between the right side surface (80a) of the tube plate (80) and the first left side surface (52c) of the front plate stack (250), the sum of the length (HX3) of the guide portion (271) in the predetermined direction (D) and the length (HX4) of the engaging portion (281) in the predetermined direction (D) is greater than the sum of the length (H2) of the heat transfer tube (42) from the right side surface (80a) and the length (H1) of the front connecting portion (53) from the first left side surface (52c).

[0133] The number of engagement portions (281) provided is the same as the number of guide portions (271). As shown in FIG. 14 , three engagement portions (281) are provided corresponding to the number of guide portions (271). The engagement portions (281) are provided separately in the first overlapping portion (52a) and the second overlapping portion (52b). One engagement portion (281) is provided in the third main front connection portion row (53c) and two engagement portions (281) are provided in the sixth main front connection portion row (53f). Note that when the guide portions (271) are provided in the first main heat transfer tube row (42a) and the fourth main heat transfer tube row (42d), the engagement portions (281) may be provided in the first main front connection portion row (53a) and the fourth main front connection portion row (53d). The engaging portions (281) are not provided in the second main front connection portion row (53b) and the fifth main front connection portion row (53e).

[0134] 15, the tip of the engagement portion 281 has a flared portion 281a. The inner diameter of the flared portion 281a is larger than the outer diameter of the narrowed portion 271a of the guide portion 271. The portion of the guide portion 271 other than the narrowed portion 271a is located in the flared portion 281a.

[0135] The front connection portion 53 that becomes the engagement portion 281 is marked to indicate that it is the engagement portion 281. The marking is achieved by changing the color of the left end of the front connection portion 53 or by attaching a mark to the left end of the front connection portion 53. The marking is provided on the outer surface of the front connection portion 53 so that it can be seen by an operator from the outside.

[0136] The rear plate stack also has an engaging portion. The configuration of the engaging portion provided on the rear plate stack is the same as the engaging portion (281) of the front plate stack (250) described above, and therefore a detailed description will be omitted. The engaging portion of the rear plate stack is provided in the first main rear connection portion row (63a). The engaging portion of the rear plate stack is not provided in the second main rear connection portion row (63b).

[0137] (10) Effects of the Second Embodiment In the second embodiment, the front heat exchange section (240A) has a guide portion (271) extending toward the front plate stack (250), and the front plate stack (250) has an engagement portion (281) that engages with the guide portion (271). Between the right side surface (80a) of the tube plate (80) and the first left side surface (52c) of the front main body section (52), the sum of the length (HX3) of the guide portion (271) in the predetermined direction (D) and the length (HX4) of the engagement portion (281) in the predetermined direction (D) is greater than the sum of the length (H1) of the front connection portion (53) from the first left side surface (52c) and the length (H2) of the heat transfer tube (42) from the tube plate (80). In the second embodiment, too, the guide portion (271) and the engaging portion (281) engage with each other before the heat transfer tube (42) and the connecting portion (53) are connected, and therefore the guide portion (271) and the engaging portion (281) can determine the positioning of the heat transfer tube (42) and the front connecting portion (53).

[0138] In the second embodiment, the guide portion (271) is a part of the heat transfer tube (42), the engaging portion (281) is a portion of the front connecting portion (53) that is connected to the guide portion (271), and the length of the guide portion (271) from the right side surface (80a) is greater than the length of the heat transfer tube (42) from the right side surface (80a). Since there is no influence of misalignment of the guide portion (271) and the engaging portion (281), it is possible to improve the accuracy of positioning of the heat transfer tube (42) and the connecting portion (53).

[0139] In particular, in the second embodiment, the length of the guide portion (271) from the right side surface (80a) is greater by 2 mm or more than the length of the heat transfer tube (42) from the right side surface (80a). The guide portion (271) has a sufficient insertion margin, so that the guide portion (271) is less likely to wobble when engaged with the engaging portion (281), and this facilitates positioning of the heat transfer tube (42) and the connecting portion (53).

[0140] In the second embodiment, the heat transfer tube (42) is inserted into the front connecting portion (53), the engaging portion (281) has a flared portion (281a) at its tip, and the guide portion (271) has a drawn portion (271a) at its tip, the outer diameter of the drawn portion (271a) being smaller than the inner diameter of the flared portion (281a). Since the guide portion (271) can be easily inserted into the engaging portion (281), the heat transfer tube (42) and the connecting portion (53) can be easily positioned.

[0141] In the second embodiment, the guide portion (271) is provided in the rearmost or frontmost front main heat transfer tube row (42a, 42c, 42d, 42f), and the engagement portion (281) is provided in the rearmost or frontmost front main connection portion row (53a, 53c, 53d, 53f). When connecting the front connection portion (53) to the heat transfer tube (42), the worker can easily view the guide portion (271) and the engagement portion (281), which facilitates positioning of the heat transfer tube (42) and the connection portion (53).

[0142] In the second embodiment, the guide portion (271) provided in the first front main heat exchange portion (43a) is located closer to the second front main heat exchange portion (43b), and the guide portion (271) provided in the second front main heat exchange portion (43b) is located closer to the first front main heat exchange portion (43a). Since the guide portions (271) are located close to each other, an operator can easily view the guide portions (271), which facilitates the positioning of the heat transfer tubes (42) and the front connection portions (53).

[0143] Third Embodiment A third embodiment of the present disclosure will be described in detail with reference to the drawings. In the following description, parts common to the first to third embodiments will be given the same reference numerals, and detailed description thereof will be omitted.

[0144] (11) Connection The front plate stack (350) according to the third embodiment differs in configuration from the front plate stacks (350) according to the first to third embodiments. Specifically, in the front plate stack (350), the front connection portion (353) is not formed of a circular pipe but is formed by providing a through hole in the plate. The inner diameter of the front connection portion (353) is slightly larger than the outer diameter of the heat transfer tube (42). The depth of the front connection portion (353) from the first left side surface (352c) is set to a length that allows the front connection portion (353) and the heat transfer tube (42) to be brazed to each other. The depth of the front connection portion (353) from the first left side surface (352c) is 2 mm or more.

[0145] As with the front plate stack (350), the rear connection portions of the rear plate stack are not formed from circular pipes but from through holes in the plates.

[0146] (12) Guide portion, engagement portion 16, in the third embodiment, the guide portion (371) is formed by a part of the heat transfer tube (42). The engagement portion (381) is formed by a part of the front connection portion (353) and a part of the rear connection portion.

[0147] (12-1) Guide section The guide portion (371) is a specific heat transfer tube that protrudes further toward the front plate stack (350) (right side) than the other heat transfer tubes (42). A fifth specific length (HX5), which is the length of the guide portion (371) from the right side surface (80a) of the tube plate (80), is longer than the second length (H2) of the other heat transfer tubes (42). Specifically, the fifth specific length (HX5) is longer than the second length (H2) by 2 mm or more.

[0148] 16, two guide portions (371) are provided. The positions at which the guide portions (371) are provided in the front heat exchange portion (340A) are the same as those in the second embodiment, and therefore detailed description thereof will be omitted.

[0149] The rear main heat exchanger is also provided with a guide portion. The configuration of the guide portion provided in the rear main heat exchanger is the same as that of the guide portion in the front heat exchanger (340A) described above, and therefore detailed description thereof will be omitted.

[0150] (12-2) Engagement part The engaging portion 381 is a front connecting portion 353 to which the guide portion 371 is connected. The depth of the engaging portion 381 from the first left side surface 352c is greater than the depth of the other front connecting portions 353 from the first left side surface 352c.

[0151] Between the right side surface (80a) of the tube plate (80) and the first left side surface (352c) of the front main body portion (352), the length of the front connecting portion (353) in the predetermined direction and the length of the engaging portion (381) in the predetermined direction (D) are 0. Therefore, between the right side surface (80a) of the tube plate (80) and the first left side surface (352c) of the front main body portion (352), the sum of the length (HX5) of the guide portion (371) in the predetermined direction (D) and the length of the engaging portion (381) in the predetermined direction (D) is greater than the sum of the length (H2) of the heat transfer tube (42) from the right side surface (80a) and the length of the front connecting portion (353) from the first left side surface (352c).

[0152] The number of engagement portions 381 provided is the same as the number of guide portions 371. As shown in Fig. 16, two engagement portions 381 are provided corresponding to the guide portions 371. The positions of the engagement portions 381 provided in the front plate assembly 350 are the same as those in the second embodiment, and therefore detailed description thereof will be omitted.

[0153] A marking is provided near the engaging portion 381 on the first left side surface 352c to indicate the engaging portion 381. The marking is, for example, a color painted around the engaging portion 381 on the first left side surface 352c. The marking is provided so that an operator can see it from outside.

[0154] The rear plate assembly also has an engagement portion. The configuration of the engagement portion provided on the rear plate assembly is the same as the engagement portion 381 of the front plate assembly 350 described above, and therefore a detailed description thereof will be omitted.

[0155] (13) Effects of the Third Embodiment When the front connection portion (353) is configured as a hole formed in the front main body portion (352) as in the third embodiment, the front connection portion (353) is difficult to see, making it difficult to position the heat transfer tube (42) and the front connection portion (353). In contrast, in the third embodiment, a part of the heat transfer tube (42) is configured as a guide portion (371), a part of the front connection portion (353) is configured as an engagement portion (381), and the guide portion (371) protrudes further toward the front plate stack (350) than the other heat transfer tubes (42). Because the guide portion (371) engages with the engagement portion (381) before the heat transfer tube (42) is connected to the front connection portion (353), the guide portion (371) and the engagement portion (381) can easily position the heat transfer tube (42) and the front connection portion (353).

[0156] Fourth Embodiment A fourth embodiment of the present disclosure will be described in detail with reference to the drawings. In the following description, parts common to the first to fourth embodiments will be given the same reference numerals, and detailed description thereof will be omitted.

[0157] (14) Guide portion, engagement portion 17 to 21, in the fourth embodiment, the front connection part (53) is formed of a connecting pipe. In the fourth embodiment, the guide part is formed of a guide pin (471) extending from the first front plate (521) toward the front heat exchange part (440A). The engagement part is formed of an engagement hole (481) that is provided in the tube plate (80) of the front heat exchange part (440A) and through which the guide pin (471) passes.

[0158] (14-1) Guide pin The guide pin (471) extends in a predetermined direction (D) from the first left side surface (52c) toward the front heat exchange section (440A). A first pin length (HP1), which is the length of the guide pin (471) from the first left side surface (52c), is greater than the sum of the second length (H2) of the heat transfer tube (42) and the first length (H1) of the front connection section (53). Specifically, the first pin length (HP1) is greater than the sum of the first length (H1) and the second length (H2) by 1 mm or more. The first pin length (HP1) is, for example, 27 mm to 35 mm.

[0159] As shown in FIG. 18 , two guide pins (471) are provided. The guide pins (471) are provided at positions that do not overlap with the fins (41) when viewed in the axial direction of the heat transfer tubes (42). One of the guide pins (471) is provided in the first overlapping portion (52a) at a rear portion of the third main front connection portion row (53c). The other guide pin (471) is provided in the second overlapping portion (52b) at a rear portion of the sixth main front connection portion row (53f). Note that the guide pins (471) may be provided in the front portion of the first main front connection portion row (53a) and the front portion of the fourth main front connection portion row (53d) instead of or in addition to the rear portions of the third main front connection portion row (53c) and the sixth main front connection portion row (53f). The guide pin (471) is not provided in the area of ​​the first front plate (521) where the front connection portion (53) is disposed.

[0160] As shown in Fig. 21, the cross section of the guide pin (471) is polygonal. Specifically, the cross section of the guide pin (471) is rectangular.

[0161] The rear plate assembly also has guide pins. The configuration of the guide pins provided on the rear plate assembly is the same as that of the guide pins on the front plate assembly (450) described above, and therefore a detailed description thereof will be omitted.

[0162] (14-2) Engagement part The engagement hole (481) is a hole with which the guide pin (471) engages. The engagement hole (481) is formed to penetrate the tube plate (80). The length of the engagement hole (481) in the predetermined direction (D) between the right side surface (80a) of the tube plate (80) and the first left side surface (52c) of the front main body portion (52) is zero. Therefore, the sum of the length (HP1) of the guide pin (471) in the predetermined direction (D) and the length of the engagement hole (481) in the predetermined direction (D) between the right side surface (80a) of the tube plate (80) and the first left side surface (52c) of the front main body portion (52) is greater than the sum of the length (H2) of the heat transfer tube (42) from the right side surface (80a) and the length of the front connecting portion (53) from the first left side surface (52c).

[0163] The number of engagement holes (481) provided is the same as the number of guide pins (471). As shown in FIG. 17 , two engagement holes (481) are provided corresponding to the guide pins (471). The engagement holes (481) are provided separately in the first front main heat exchange section (43a) and the second front main heat exchange section (43b). The engagement holes (481) are provided at positions that do not overlap with the fins (41) when viewed in the axial direction of the heat transfer tubes (42). The engagement holes (481) are provided in the tube plate (80) at a rear portion of the third main heat transfer tube row (42c) and at a rear portion of the sixth main heat transfer tube row (42f). When the guide pins (471) are provided in the front portions of the first main front connection portion row (53a) and the fourth main front connection portion row (53d) in the front plate stack (450), the engagement holes (481) are provided in the front portions of the first main heat transfer tube row (42a) and the fourth main heat transfer tube row (42d). The engagement holes (481) are not provided in the region of the tube plate (80) where the heat transfer tubes (42) are arranged.

[0164] 21, the cross section of the engagement hole (481) is polygonal similar to the cross section of the guide pin (471). In this example, the cross section of the engagement hole (481) is rectangular.

[0165] The rear heat exchanger also has an engagement hole. The configuration of the engagement hole in the rear heat exchanger is the same as the engagement hole (481) in the front heat exchanger (440A) described above, and therefore detailed description thereof will be omitted.

[0166] (15) Assembling the heat exchange section and plate stack The assembly of the heat exchange section and the plate stack will be described by taking as an example the assembly of the front heat exchange section (440A) and the front plate stack (450).

[0167] First, as shown in Fig. 17, the front heat exchange section (440A) and the front plate stack (50) are arranged so that the front heat exchange section (440A) is on the lower side and the front plate stack (450) is on the upper side. The front heat exchange section (440A) is arranged so that the engagement hole (481) is located on the front side as seen by an operator. The front plate stack (450) is arranged so that the guide pin (471) is located on the front side as seen by an operator so that the guide pin (471) is visible.

[0168] 19, the front heat exchange section (440A) and the front plate stack (450) are brought closer to each other in a predetermined direction (D) to engage the engagement holes (481) with the guide pins (471). At this time, the heat transfer tubes (42) and the front connecting sections (53) other than the engagement holes (481) and the guide pins (471) are not yet engaged.

[0169] 20 , with the engagement holes (481) and the guide pins (471) still engaged, the front heat exchange unit (440A) and the front plate stack (450) are moved closer to each other in a predetermined direction (D) to engage the heat transfer tubes (42) with the front connection portions (53). Because the positioning of the heat transfer tubes (42) and the front connection portions (53) has been completed by the engagement holes (481) and the guide pins (471), the heat transfer tubes (42) can be easily engaged with the front connection portions (53).

[0170] After the heat transfer tube (42) and the front connecting portion (53) are engaged with each other, the heat transfer tube (42) and the front connecting portion (53) are connected by burner brazing.

[0171] (16) Effects of the fourth embodiment In the fourth embodiment, the front plate stack (450) has a guide pin (471) extending toward the front heat exchange section (40A), and the front heat exchange section (440A) has an engagement hole (481) that engages with the guide pin (471). Between the right side surface (80a) of the tube plate (80) and the first left side surface (52c) of the front main body section (52), the sum of the length (HP1) of the guide pin (471) in the predetermined direction (D) and the length of the engagement hole (481) in the predetermined direction (D) is greater than the sum of the length (H1) of the front connection section (53) from the first left side surface (52c) and the length (H2) of the heat transfer tube (42) from the tube plate (80). Since the guide pin (471) engages with the engagement hole (481) before the heat transfer tube (42) and the connection portion (53) are connected, the heat transfer tube (42) and the front connection portion (53) can be positioned by the guide pin (471) and the engagement hole (481).

[0172] In the fourth embodiment, the guide pin (471) and the engagement hole (481) are positioned so as not to overlap with the fins (41) when viewed in the axial direction of the heat transfer tube (42). When the guide pin (471) is inserted into the engagement hole (481), there is no risk of the guide pin (471) interfering with the fins (41), and therefore the guide pin (471) can be made longer. The longer guide pin (471) provides a sufficient insertion margin, which makes the guide pin (471) less likely to wobble when inserted into the engagement hole (481), facilitating positioning of the heat transfer tube (42) and the connection portion (53).

[0173] In the fourth embodiment, the length of the guide pin (471) is 1 mm or more longer than the sum of the length of the heat transfer tube (42) from the tube plate (80) and the length of the connection portion (53) from the predetermined surface (52c). Since the guide pin (471) has a sufficient insertion margin, the guide pin (471) is less likely to wobble when inserted into the engagement hole (481), and this makes it easier to position the heat transfer tube (42) and the connection portion (53).

[0174] In the fourth embodiment, the pin (471) has a polygonal cross-sectional shape, and the engagement hole (481), when viewed in the hole axial direction, has a polygonal cross-sectional shape similar to that of the guide pin (471). When the front heat exchange section (40A) and the front plate assembly (450) attempt to rotate relative to each other around the pin (471), the corners of the pin (471) abut against the inner circumferential surface of the engagement hole (481), thereby preventing the front heat exchange section (440A) and the front plate assembly (450) from rotating relative to each other. In particular, even when there is only one pair of the guide pin (471) and the engagement hole (481), the front heat exchange section (40A) and the front plate assembly (450) can be prevented from rotating relative to each other. This facilitates the positioning of the heat transfer tube (42) and the connection portion (53).

[0175] In the fourth embodiment, the guide pin (471) is provided in a portion of the first front plate (521) rearward of the rearmost main front connection portion row (53c, 53f), and the engagement hole (481) is provided in the rearmost main heat transfer tube row (42c, 42f) of the tube plate (80). When connecting the front connection portion (53) and the heat transfer tube (42), the worker can easily view the guide pin (471) and the engagement hole (481), which facilitates positioning of the heat transfer tube (42) and the connection portion (53).

[0176] Fifth Embodiment A fifth embodiment of the present disclosure will be described in detail with reference to the drawings. In the following description, parts common to the first to fifth embodiments will be given the same reference numerals, and detailed description thereof will be omitted.

[0177] (17) Guide portion, engagement portion 22, in the fifth embodiment, the guide portion is formed of a guide pin (571) extending from the tube plate (80) of the front heat exchange section (540A) toward the front plate stack (550). The engagement portion (581) is formed of an engagement hole (581) that is provided in the front plate stack (550) and through which the guide pin (571) passes.

[0178] (17-1) Guide pin The guide pin (571) extends in a predetermined direction (D) from the right side surface (80a) of the tube plate (80) toward the front plate stack (550). A second pin length (HP2), which is the length of the guide pin (571) from the right side surface (80a), is greater than the sum of the second length (H2) of the heat transfer tube (42) and the first length (H1) of the front connection portion (53). Specifically, the second pin length (HP2) is greater than the sum of the first length (H1) and the second length (H2) by 1 mm or more. The second pin length (HP2) is a length that prevents the tip of the guide pin (571) from penetrating the front plate stack (550) when the heat transfer tube (42) and the front connection portion (53) are connected. The second pin length (HP2) is, for example, 27 mm to 35 mm.

[0179] As shown in FIG. 22 , two guide pins (571) are provided. The guide pins (571) are provided separately in the first front main heat exchange section (43a) and the second front main heat exchange section (43b). The guide pins (571) are provided at positions that do not overlap with the fins (41) when viewed in the axial direction of the heat transfer tubes (42). One guide pin (571) is provided in a rear portion of the third main heat transfer tube array (42c) and in a rear portion of the sixth main heat transfer tube array (42f). Note that the guide pins (571) may be provided in the first main heat transfer tube array (42a) and the fourth main heat transfer tube array (42d) instead of or in addition to the rear portions of the third main heat transfer tube array (42c) and the sixth main heat transfer tube array (42f). The guide pins (571) are not provided in the region of the tube plate (80) where the heat transfer tubes (42) are arranged.

[0180] Although not shown, the cross section of the guide pin (571) is polygonal.

[0181] The rear main heat exchanger is also provided with guide pins. The configuration of the guide pins provided in the rear main heat exchanger is the same as that of the guide pins in the front heat exchanger (540A) described above, and therefore detailed description thereof will be omitted.

[0182] (17-2) Engagement hole The engagement hole (581) is a hole with which the guide pin (571) engages. The engagement hole (581) is formed to penetrate the first front plate (521), the second front plate (522), the third front plate (523), and the fourth front plate (524). The length of the engagement hole (581) in the predetermined direction (D) is zero between the right side surface (80a) of the tube plate (80) and the first left side surface (52c) of the front main body portion (52). Therefore, between the right side surface (80a) of the tube plate (80) and the first left side surface (52c) of the front main body portion (52), the sum of the length (HP2) of the guide pin (571) in the specified direction (D) and the length of the engagement hole (581) in the specified direction (D) is greater than the sum of the length (H2) from the right side surface (80a) of the heat transfer tube (42) and the length from the first left side surface (52c) of the front connection portion (53).

[0183] The number of engagement holes (581) provided is the same as the number of guide pins (571). As shown in FIG. 22 , two engagement holes (481) are provided corresponding to the guide pins (571). The engagement holes (581) are provided separately in the first overlapping portion (52a) and the second overlapping portion (52b). The engagement holes (581) are provided at positions that do not overlap with the fins (41) when viewed in the axial direction of the heat transfer tube (42). The engagement holes (581) are provided in the first front plate (521) at a rear portion of the third main front connection portion row (53c) and at a rear portion of the sixth main front connection portion row (53f). When the guide pins (571) are provided in the tube plate (80) in front of the first main heat transfer tube row (42a) and in front of the first main heat transfer tube row (42a), the engagement holes (481) are provided in front of the first main front connection portion row (53a) and in front of the fourth main front connection portion row (53d). The engagement holes (581) are not provided in the region of the first front plate (521) where the front connection portions (53) are arranged.

[0184] Although not shown, the cross section of the engagement hole (581) is polygonal similar to the cross section of the guide pin (471).

[0185] The rear plate assembly also has an engagement hole. The configuration of the engagement portion provided on the rear plate assembly is the same as the engagement hole (581) of the front plate assembly (550) described above, so a detailed description will be omitted.

[0186] (18) Effects of the fifth embodiment In this embodiment 5, the front heat exchange section (540A) has a guide pin (571) extending toward the front plate stack (550), and the front plate stack (550) has an engagement hole (581) that engages with the guide pin (571). Between the right side surface (80a) of the tube plate (80) and the first left side surface (52c) of the front main body section (52), the sum of the length (HP2) of the guide pin (571) in the specified direction (D) and the length of the engagement hole (581) in the specified direction (D) is greater than the sum of the length (H1) of the front connection section (53) from the first left side surface (52c) and the length (H2) of the heat transfer tube (42) from the tube plate (80). Since the guide pin (571) engages with the engagement hole (581) before the heat transfer tube (42) and the connection portion (53) are connected, the heat transfer tube (42) and the front connection portion (53) can be positioned by the guide pin (571) and the engagement hole (581).

[0187] In the fifth embodiment, the length of the guide pin (571) is 1 mm or more longer than the sum of the length of the heat transfer tube (42) from the tube plate (80) and the length of the front connection portion (53) from the first left side surface (52c). Because the guide pin (571) has a sufficient insertion margin, the guide pin (571) is less likely to wobble when inserted into the engagement hole (581), facilitating the positioning of the heat transfer tube (42) and the connection portion (53).

[0188] In the fifth embodiment, the guide pin (571) is provided in a portion of the tube plate (80) rearward of the rearmost main heat transfer tube row (42c, 42f), and the engagement hole (581) is provided in a portion of the first front plate (521) rearward of the rearmost main front connection portion row (53c, 53f). When connecting the front connection portion (53) and the heat transfer tube (42), the worker can easily view the guide pin (571) and the engagement hole (581), which facilitates positioning of the heat transfer tube (42) and the connection portion (53).

[0189] (19) Other embodiments The heat exchanger may be applied to an outdoor heat exchanger (22) of an outdoor unit (20).

[0190] The indoor heat exchanger (40) does not have to be of a fin-and-tube type, but may be of a corrugated type in which corrugated fins are arranged between adjacent heat transfer tubes.

[0191] The heat exchanger body (B) may have a single heat exchange section, without including the front heat exchange section (40A, 240A, 340A, 440A, 540A) and the rear heat exchange section (40B). In this case, the first internal pipe (38), the second internal pipe (39), and the indoor expansion valve (37) are omitted.

[0192] The front body portion 52, 352 and the rear body portion 62 may be formed of a single plate instead of a plate stack. Such a plate structure can be manufactured by sintering metal powder using a 3D printer.

[0193] In the first embodiment, the guide portion is made up of a part of the front connection portion (53) and a part of the rear connection portion (63), and the engaging portion is made up of the heat transfer tube (42) at a position facing the guide portion. In the second embodiment, the guide portion is made up of a part of the heat transfer tube (42), and the engaging portion is made up of the front connection portion (53) and the rear connection portion (63) at positions facing the guide portion. However, the present invention is not limited to this, and the guide portion may be made up of a part of the front connection portion (53), a part of the rear connection portion (63), and a part of the heat transfer tube (42), and the engaging portion may be made up of the front connection portion (53), the rear connection portion (63), and the heat transfer tube (42) at positions facing the guide portion.

[0194] In the fourth embodiment, the guide pins are provided in the first front plate (521), and the engagement holes are provided in the tube plate (80). In the fifth embodiment, the guide portions are provided in the tube plate (80), and the engagement holes are provided in the first front plate (521). However, the present invention is not limited to this. Guide pins may be provided in both the first front plate (521) and the tube plate (80), and engagement holes may be provided in portions of the first front plate (521) and the tube plate (80) that face the guide pins.

[0195] The cross-sectional shape of the guide pins (471, 571) may be elliptical instead of polygonal.

[0196] The guide pins (471, 571) may have a circular cross section, in which case two or more pairs of guide pins (471, 571) and engagement holes (481, 581) are provided.

[0197] Although the embodiments 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. Furthermore, the above embodiments, modifications, and other embodiments may be combined or substituted as appropriate as long as the functionality of the subject matter of the present disclosure is not impaired.

[0198] The terms "first," "second," "third," etc. mentioned above are used to distinguish the terms to which these terms are attached, and do not limit the number or order of the terms. [Industrial Applicability]

[0199] INDUSTRIAL APPLICABILITY As described above, the present disclosure is useful for heat exchangers, refrigeration cycle devices, and air conditioner indoor units. [Explanation of symbols]

[0200] 11 Refrigerant circuit 31 Casing 41 Finn 42 Heat transfer tube 50 Front plate stack 51 refrigerant flow path 52 Front body part 52c 1st left side (predetermined surface) 53 Front connection part 60 Rear plate stack 61 Refrigerant flow path 62 Rear main body 62a Second left side (specified side) 63 Rear connection part 71 Guide part 71a Constriction section 80 tube sheet 81 Engagement part 81a flare section 240A Front heat exchanger 250 Front Plate Stack 271 Guide part 271a Constriction section 281 Engagement part 281a Flare section 340A Front heat exchange section 350 Front Plate Stack 352 Front body part 352c 1st left side (predetermined surface) 353 Front connection part 371 Guide part 381 Engagement part 440A Front heat exchange section 450 Front Plate Stack 471 Guide Pin 481 Engagement hole 540A Front heat exchange section 550 Front Plate Stack 571 Guide pin 581 Engagement hole D Specified direction

Claims

1. a heat exchange section (40A, 240A, 340A, 440A, 540A) having fins (41), a plurality of heat transfer tubes (42), and a tube plate (80) located at an end of the heat transfer tubes (42) in a predetermined direction (D), which is the axial direction of the heat transfer tubes (42), and through which the heat transfer tubes (42) penetrate; a plate structure (50, 250, 350, 450, 550) having a main body (52, 352) including a refrigerant flow path (51) communicating with a plurality of the heat transfer tubes (42), and a plurality of connection portions (53, 353) communicating with the refrigerant flow path (51) and to which the heat transfer tubes (42) are connected, At least one of the heat exchange section (40A, 240A, 340A, 440A, 540A) and the plate structure (50, 250, 350, 450, 550) has a guide section (71, 271, 371, 471, 571) extending toward the other, at least the other of the heat exchange portion (40A, 240A, 340A, 440A, 540A) and the plate structure (50, 250, 350, 450, 550) has an engaging portion (81, 281, 381, 481, 581) that engages with the guide portion (71, 271, 371, 471, 571), a heat exchanger in which, between a surface (80a) of the tube sheet (80) facing the plate structure (50, 250, 350, 450, 550) and a predetermined surface (52c, 352c) that is a surface of the main body (52, 352) facing the heat exchange section (40A, 240A, 340A, 440A, 540A), a sum of a length of the guide section (71, 271, 371, 471, 571) in the predetermined direction (D) and a length of an engagement section (81, 281, 381, 481, 581) in the predetermined direction (D) is greater than a sum of a length from the predetermined surface (52c, 352c) of the connection section (53, 353) to a tip thereof and a length from the tube sheet (80) to a tip of the heat transfer tube (42).

2. 2. The heat exchanger according to claim 1, the connection portion (53) is a connection pipe protruding from the predetermined surface (52c) toward the heat exchange portion (40A, 240A, 340A, 440A, 540A), the guide portion (71, 271) is a part of the heat transfer tube (42) or a part of the connection portion (53); the engaging portion (81, 281) is a portion of the heat transfer tube (42) or the connecting portion (53) that is connected to the guide portion (71, 271); When the guide portion (71) is the connecting portion (53), the length of the guide portion (71) from the specified surface (52c) is greater than the length of the connecting portion (53) from the specified surface (52c) to the tip, while when the guide portion (271) is the heat transfer tube (42), the length of the guide portion (271) from the tube plate (80) is greater than the length of the heat transfer tube (42) from the tube plate (80).

3. 3. The heat exchanger according to claim 2, When the guide portion (71) is the connecting portion (53), the length of the guide portion (71) from the specified surface (52c) is greater than the length of the connecting portion (53) from the specified surface (52c) to its tip by 2 mm or more, while when the guide portion (271) is the heat transfer tube (42), the length of the guide portion (271) from the tube plate (80) is greater than the length of the heat transfer tube (42) from the tube plate (80) to its tip by 2 mm or more.

4. 4. The heat exchanger according to claim 2 or 3, the number of the guide portions (71, 271) is two or more; A heat exchanger in which the number of the engagement portions (81, 281) is the same as the number of the guide portions (71, 271).

5. 4. The heat exchanger according to claim 2 or 3, the guide portion (71) is a part of the connection portion (53), the engaging portion (81) is a part of the heat transfer tube (42), The connection portion (53) is inserted inside the heat transfer tube (42), The engaging portion (81) has a flared portion (81a) at its tip, The tip of the guide portion (71) has a drawn portion (71a) formed by drawing, The heat exchanger has an outer diameter of the throttle portion (71a) smaller than an inner diameter of the flare portion (81a).

6. 4. The heat exchanger according to claim 2 or 3, the guide portion (271) is a part of the heat transfer tube (42), the engaging portion (281) is a part of the connecting portion (53), The heat transfer tube (42) is inserted into the connecting portion (53), The engaging portion (281) has a flared portion (281a) at a tip end thereof, The tip of the guide portion (271) has a drawn portion (271a) formed by drawing, A heat exchanger in which the outer diameter of the throttle portion (271a) is smaller than the inner diameter of the flared portion (281a).

7. 2. The heat exchanger according to claim 1, the guide portion is a pin (471, 571) provided on at least one of the heat exchange portion (440A, 540A) and the plate structure (450, 550), The engagement portion is a hole (481, 581) provided in at least the other of the heat exchange portion (440A, 540A) and the plate structure (450, 550).

8. 8. The heat exchanger according to claim 7, The heat exchanger, wherein the pins (471, 571) and the holes (481, 581) are provided at positions that do not overlap with the fins (41) when viewed in the axial direction of the heat transfer tubes (42).

9. 9. The heat exchanger according to claim 7 or 8, The length of the pin (471, 571) is at least 1 mm longer than the sum of the length from the tube plate (80) to the tip of the heat transfer tube (42) and the length from the specified surface (52c) to the tip of the connection portion (53).

10. 9. The heat exchanger according to claim 7, The cross-sectional shape of the pin (471, 571) is polygonal, The heat exchanger, wherein the hole (481, 581) has a polygonal shape similar to the cross-sectional shape of the pin (471, 571) when viewed in the hole axial direction.

11. A refrigeration cycle device comprising a refrigerant circuit (11) to which the heat exchanger according to any one of claims 1 to 3, 7 and 8 is connected.

12. A heat exchanger according to any one of claims 1 to 3, 7 and 8; an air conditioning indoor unit comprising: a casing (31) that houses the heat exchanger;

13. A method for manufacturing a heat exchanger, comprising: The heat exchanger comprises: a heat exchange section (40A, 240A, 340A, 440A, 540A) having fins (41), a plurality of heat transfer tubes (42), and a tube plate (80) located at an end of the heat transfer tubes (42) in a predetermined direction (D), which is the axial direction of the heat transfer tubes (42), and through which the heat transfer tubes (42) penetrate; a plate structure (50, 250, 350, 450, 550) having a main body including a refrigerant flow path (51) communicating with the plurality of heat transfer tubes (42), and a plurality of connection portions (53, 353) communicating with the refrigerant flow path (51) and to which the heat transfer tubes (42) are connected; Equipped with one of the heat exchange section (40A, 240A, 340A, 440A, 540A) and the plate structure (50, 250, 350, 450, 550) has a guide section (71, 271, 371, 471, 571) extending toward the other, the other of the heat exchange portion (40A, 240A, 340A, 440A, 540A) and the plate structure (50, 250, 350, 450, 550) has an engaging portion (81, 281, 381, 481, 581) that engages with the guide portion (71, 271, 371, 471, 571), a sum of a length of the guide portions (71, 271, 371, 471, 571) in the predetermined direction (D) between a surface (80a) of the tube sheet (80) on the plate structure (50, 250, 350, 450, 550) side and a predetermined surface (52c, 352c) that is a surface of the main body portion (52, 352) on the heat exchange portion (40A, 240A, 340A, 440A, 540A) side is greater than a sum of a length of the heat transfer tube (42) from the tube sheet (80) to a tip thereof and a length of the connection portion (53, 353) from the predetermined surface (52c, 352c) to a tip thereof, a first step of bringing the heat exchange portion (40A, 240A, 340A, 440A, 540A) and the plate structure (50, 250, 350, 450, 550) closer to each other in the predetermined direction (D) to engage the guide portion (71, 271, 371, 471, 571) with the engagement portion (81, 281, 381, 481, 581); and a second step of, after the first step, bringing the heat exchange section (40A, 240A, 340A, 440A, 540A) and the plate structure (50, 250, 350, 450, 550) closer to each other in the predetermined direction (D) while keeping the guide section (71, 271, 371, 471, 571) and the engagement section (81, 281, 381, 481, 581) engaged with each other, thereby connecting the heat transfer tube (42) and the connection section (53, 353).

Citation Information

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