Indoor heat exchanger and air-conditioning indoor unit

Abstract

This indoor heat exchanger comprises plate stacked bodies (50, 60) having: first plate parts (50A, 60A) which are disposed adjacent to a heat exchange part (B) in a first direction and have one or more plates (52, 62); and second plate parts (50B 60B) which have one or more plates (52, 62) having different shapes than the plates (52, 62) of the first plate parts (50A, 60A), and which are disposed on the surfaces on the opposite side of heat exchange part (B)-facing surfaces of the first plate parts (50A, 60A), wherein in the plate stacked bodies (50, 60), step sections (X) are formed at peripheral edge sections of the surfaces on the opposite side of the heat exchange part (B)-facing surfaces, and the step sections (X) are formed by the first plate parts (50A, 60A) and the second plate parts (50B, 60B).

Description

Indoor heat exchanger and air conditioning indoor unit

[0001] The present disclosure relates to an indoor heat exchanger and an air conditioning indoor unit.

[0002] Patent Document 1 discloses a stacked header connected to a heat exchanger. Each plate constituting the stacked header has a groove formed therein. By stacking multiple plates with such grooves, the grooves form refrigerant flow paths inside the stacked header.

[0003] International Publication No. 2014 / 184917

[0004] All plates that make up the plate stack are formed to have the same shape. The shape and position of the grooves formed in the plates vary depending on the structure of the refrigerant flow path. Therefore, the area of ​​the region without grooves varies depending on the plate. Since the region without grooves has no use, if that region is relatively large, the space inside the air conditioner cannot be used effectively.

[0005] An object of the present disclosure is to provide a laminate plate that can effectively utilize the space inside an air conditioning indoor unit.

[0006] A first aspect of the present invention is a heat exchanger including a heat exchange section (B) including a plurality of fins (41) and a plurality of heat transfer tubes (42) penetrating the plurality of fins (41); and a plate stack (50, 60) having a flow path (51, 61) therein communicating with the heat transfer tubes (42), and including a plurality of plates (52, 62) stacked in a first direction in which the heat transfer tubes (42) extend, wherein the plate stack (50, 60) includes: a first plate portion (50A, 60A) arranged adjacent to the heat exchange section (B) in the first direction and having one or more of the plates (52, 62); an indoor heat exchanger including one or more plates (52, 62) having a shape different from that of the plates (52, 62) of the first plate portion (50A, 60A) and a second plate portion (50B, 60B) arranged on a surface of the first plate portion (50A, 60A) opposite to a surface facing the heat exchange portion (B); a step portion (X) is formed in a peripheral portion of a second surface (502, 602) of the plate stack (50, 60) opposite to a first surface (501, 601) facing the heat exchange portion (B); and the step portion (X) is formed by the first plate portion (50A, 60A) and the second plate portion (50B, 60B).

[0007] In the first aspect, by providing a step portion (X) in the plate stack (50, 60), a space can be formed at a position opposite the step portion (X). This space can be effectively utilized, for example, by arranging a predetermined component in the space.

[0008] A second aspect is an air conditioning indoor unit comprising: the indoor heat exchanger of the first aspect; a casing (31) that houses the indoor heat exchanger; and a first component (300) that is arranged in the casing (31), wherein at least a part of the first component (300) is arranged to face the step portion (X) in the first direction.

[0009] In the second aspect, the first component (300) is disposed in a space facing the first direction side of the step (X), thereby shortening the combined length of the indoor heat exchanger and the first component (300), thereby realizing a more compact air conditioning indoor unit.

[0010] The third aspect is the second aspect, wherein, when the plate stack (50, 60) is viewed from the first direction, the first component (300) is arranged closer to the step portion (X) than the end of the second plate portion (50B, 60B) that constitutes the step portion (X).

[0011] In the third aspect, by arranging the first component (300) in the space below (on the step side of) the end face of the second plate portion of the step portion (X), it is possible to achieve a compact air conditioning indoor unit, as in the second aspect.

[0012] A fourth aspect is the second aspect, wherein at least a part of the first component (300) is disposed inside the step portion (X).

[0013] In the fourth aspect, by disposing at least a part of the first component (300) on the step (X), it is possible to achieve a compact air conditioning indoor unit, as in the second aspect.

[0014] A fifth aspect is the second aspect, further comprising: a second component (200) adjacent to the indoor heat exchanger (40) and facing the step portion (X) in the first direction; and a partition plate (100) arranged between the indoor heat exchanger (40) and the second component (200), wherein the partition plate (100) has a recess (101) formed to follow the shape of the step portion (X).

[0015] In the fifth aspect, the second component (200) can be disposed in the recess (101), thereby reducing the combined length of the indoor heat exchanger (40) and the second component (200), thereby achieving a more compact air conditioning indoor unit.

[0016] A sixth aspect is any one of the second to fifth aspects, wherein the casing (31) is formed with an air passage (P) through which air flows from an inlet (33) formed in the casing (31) toward an outlet (34), the indoor heat exchanger (40) is disposed in the air passage (P), and the stepped portion (X) is formed on a downstream side of the air flow in the plate stack (50, 60) as viewed from the first direction.

[0017] Here, in the indoor heat exchanger, the load is higher on the upstream side of the air flow passing through the indoor heat exchanger than on the downstream side. In contrast, in the sixth aspect, the step portion (X) is formed on the downstream side of the air flow in the plate stack (50, 60), allowing for a larger number of plates (52, 62) stacked on the upstream side of the air flow. Increasing the number of plates (52, 62) increases the thickness of the plate stack (50, 60), thereby ensuring a sufficient number of flow paths (51, 61) formed therein. Ensuring a sufficient number of flow paths allows for an increased flow rate of refrigerant flowing through the heat transfer tube (42), thereby improving heat exchange. In this way, active heat exchange can be achieved in the upstream portion of the air flow of the indoor heat exchanger, where the air conditioning load is relatively high, thereby improving the heat exchange efficiency of the indoor heat exchanger.

[0018] A seventh aspect is any one of the second to sixth aspects, wherein the plate stack (50, 60) is composed of three or more of the plates (52, 62), and in the plate stack (50, 60), the plates (52, 62) of the first plate portion (50A, 60A) closest to the heat exchange portion (B) are first end plates (521, 621), the plates (52, 62) of the second plate portion (50B, 60B) farthest from the heat exchange portion (B) are second end plates (525, 625), and the plates (52, 62) arranged between the first end plates (521, 621) and the second end plates (525, 625) are intermediate plates (522 to 524, 622 to 624), The flow paths (51, 61) are formed to pass through the intermediate plates (522-524, 622-624), and the thickness of the intermediate plates (522-524, 622-624) is greater than the thickness of the first end plates (521, 621) and the second end plates (525, 625).

[0019] In the seventh aspect, the thickness of the central plate (52, 62) of the plate stack (50, 60) is made thicker than the thickness of the plates (52, 62) arranged at both ends of the plate stack (50, 60), thereby making it possible to increase the cross-sectional area or inner diameter of the refrigerant flow paths (51, 61) formed in the plate stack (50, 60), thereby suppressing an increase in pressure loss of the refrigerant flowing through the refrigerant flow paths (51, 61).

[0020] An eighth aspect is any one of the second to seventh aspects, wherein at least a part of the first surface (501, 601) and the second surface (502, 602) of the plate stack (50, 60) is subjected to anticorrosion treatment.

[0021] In the eighth aspect, although there is a risk of electrolytic corrosion on both side surfaces of the plate stack (50, 60) due to condensation or the like, such electrolytic corrosion can be suppressed by the anticorrosion treatment.

[0022] A ninth aspect is any one of the second to eighth aspects, wherein, when viewing the plate stack (50, 60) from the first direction, the area of ​​the portion of the first plate portion (50A, 60A) that is not overlapped with the second plate portion (50B, 60B) is smaller than the area of ​​the portion where the second plate portion (50B, 60B) overlaps.

[0023] In the ninth aspect, the portion of the plate stack (50, 60) where the first plate portion (50A, 60A) and the second plate portion (50B, 60B) overlap is thicker than the portion consisting of only the first plate portion (50A, 60A), thereby ensuring a sufficient number of flow paths. The greater the number of flow paths (51, 61), the greater the heat exchange in the heat exchange section (B). Therefore, by making the portion where the first plate portion (50A, 60A) and the second plate portion (50B, 60B) overlap wider than the portion consisting of only the first plate portion (50A, 60A), a sufficient number of flow paths can be formed in the plate stack (50, 60), thereby preventing a decrease in the performance of the indoor heat exchanger.

[0024] A tenth aspect is any one of the second to ninth aspects, wherein the flow paths (51, 61) include a first flow path (51A) provided in the first plate portion (50A, 60A) and a second flow path (51B) provided across the first plate portion (50A, 60A) and the second plate portion (50B, 60B), and the second flow path (51B) is formed so as to intersect with the first flow path (51A).

[0025] In the tenth aspect, in the portion of the plate stack (50, 60) where the flow paths (51, 61) do not intersect, the flow paths (51, 61) need only be provided in the first plate portion (50A, 60A). In such a portion, the second plate portion (50B, 60B) is not required, and therefore, a step portion (X) can be provided. In this manner, the space formed by the step portion (X) can be effectively utilized.

[0026] An eleventh aspect is any one of the second to tenth aspects, wherein the flow paths (51, 61) have a third flow path (51C) formed in a portion of the first plate portion (50A, 60A) that does not overlap with the second plate portion (50B, 60B) when the plate stack (50, 60) is viewed from the first direction, and a refrigerant in a superheated region flows through the third flow path (51C) when the indoor heat exchanger functions as an evaporator, and a refrigerant in a subcooled region flows through the third flow path (51C) when the indoor heat exchanger functions as a radiator.

[0027] In the eleventh aspect, the temperature of the refrigerant in the superheated region or the supercooled region is relatively different from the temperature of the refrigerant flowing in the heat transfer tube (42) or the plate stack (50, 60). Therefore, if the flow path (51, 61) through which the refrigerant in the superheated region or the supercooled region flows and the flow path (51, 61) through which other refrigerants flow are located close to each other, heat exchange will occur between them. However, in the eleventh aspect, the third flow path (51C) is positioned away from the other flow paths (51, 61), thereby suppressing temperature exchange between the refrigerant in the superheated region or the supercooled region and the other refrigerants.

[0028] A twelfth aspect is any one of the second to eleventh aspects, further comprising a gas pipe (12a) that conveys compressed refrigerant gas to the indoor heat exchanger (40), and the gas pipe (12a) is connected to the flow path (51, 61) that is formed in a portion of the plate stack (50, 60) where the first plate portion (50A, 60A) and the second plate portion (50B, 60B) overlap.

[0029] In the twelfth aspect, the gas refrigerant has a relatively high pressure. Therefore, the thickness of the portion where the first plate portion (50A, 60A) and the second plate portion (50B, 60B) overlap is greater than the thickness of the portion where only the first plate portion (50A) exists, thereby increasing the length of the flow path extending in the stacking direction. By connecting the gas pipe (12a) to such a portion, pressure loss of the refrigerant flowing through the flow path (51, 61) when the gas pipe (12a) enters the plate stack (50, 60) can be reduced.

[0030] FIG. 1 is a piping diagram of an air conditioning apparatus according to an embodiment. FIG. 2 is a front view of an air conditioning indoor unit. FIG. 3 is a cross-sectional view of the air conditioning indoor unit taken along line II-II. FIG. 4 is a front view showing the internal structure of the air conditioning indoor unit. FIG. 5 is an enlarged perspective view of a main portion of an indoor heat exchanger. FIG. 6 is a view of a plate stack as viewed from the right. FIG. 7 is a cross-sectional view illustrating an example of a refrigerant flow path of the plate stack. FIG. 8 is a schematic view of a front plate stack as viewed from the front. FIG. 9 is a cross-sectional view of the front plate stack for illustrating the configuration of a first flow path. FIG. 10 is a cross-sectional view of the front plate stack for illustrating the configuration of a second flow path. FIG. 11 is a schematic view of the plate stack as viewed from the first direction (rightward), showing that the first flow path and the second flow path intersect. FIG. 12 is a cross-sectional view of the front plate stack for illustrating the configuration of a third flow path. FIG. 13 is a view of a rear plate stack according to a modified example as viewed from the first direction (rightward). FIG. 14 is a cross-sectional view of the rear plate stack for illustrating the configuration of the third flow path. Fig. 15 is a schematic diagram of a portion of the internal structure of an air conditioning indoor unit according to another embodiment, viewed from the front. Fig. 16 is a schematic diagram of a portion of the internal structure of an air conditioning indoor unit according to another embodiment, viewed from the front. Fig. 17 is a schematic diagram of a portion of the internal structure of an air conditioning indoor unit according to another embodiment, viewed from the front. Fig. 18 is a schematic diagram of a portion of the internal structure of an air conditioning indoor unit according to another embodiment, viewed from the front.

[0031] 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.

[0032] (1) Overall Configuration of Air Conditioner This 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.

[0033] As shown in Fig. 1, the air conditioner (10) is an example of a refrigeration cycle apparatus 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.

[0034] The air conditioner (10) includes an air conditioning outdoor unit (20), an air conditioning indoor unit (30), a first interconnecting pipe (12), and a second interconnecting pipe (13). The air conditioner (10) is a pair type having one air conditioning outdoor unit (20) and one air conditioning indoor unit (30). The first interconnecting pipe (12) is a gas interconnecting pipe, and the second interconnecting pipe (13) is a liquid interconnecting pipe.

[0035] The air conditioner 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 switching valve (24), and an outdoor fan (25) housed in the outdoor casing (20a).

[0036] 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 (the state indicated by the solid line in FIG. 1 ) and a second state (the state indicated by the dashed line in FIG. 1 ). In the first state, the four-way selector valve (24) communicates the discharge port of the compressor (21) with the gas end of the outdoor heat exchanger (22) and also communicates the suction port of the compressor (21) with 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.

[0037] The air conditioner 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).

[0038] (2) Air Conditioning Indoor Unit The air conditioning indoor unit (30), which is an indoor air conditioner, will be described in detail with reference to Figures 2 to 4. The air conditioning indoor unit (30) of this embodiment is a wall-mounted type that is installed on a wall of the indoor space (I). Note that the terms "upper," "lower," "right," "left," "front," and "rear" described below correspond to the directions of the arrows shown in Figures 2 and 3, and the left-right directions are based on the case where the casing (31) is viewed from the front.

[0039] 2 and 3, the casing (31) is formed in the shape of a horizontally long box. The casing (31) has a front plate (31a), a rear plate (31b), an upper plate (31c), a lower plate (31d), a first side plate (31e), and a second side plate (31f).

[0040] 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).

[0041] 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).

[0042] (2-2) Filter The air conditioner 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 air conditioner indoor unit (30) may include a dust removal mechanism that removes the dust collected by the filter (35).

[0043] (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).

[0044] (2-4) Indoor Fan The indoor fan (32) is arranged in the air passage (P). The indoor fan (32) is arranged 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).

[0045] (2-5) Flap The air conditioner 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 air conditioner indoor unit (30) may have a plurality of flaps (36). The flap (36) may adjust the air direction in the horizontal direction.

[0046] (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).

[0047] (3-1) Indoor Heat Exchanger The indoor heat exchanger (40) shown in Figures 3 to 5 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.

[0048] The heat exchanger body (B) is an example of a heat exchange section (B). The heat exchanger body (B) includes a plurality of fins (41) and a plurality of heat transfer tubes (42) penetrating the plurality of fins (41). The plurality of fins (41) are arranged in the longitudinal direction of the casing (31). The plurality of heat transfer tubes (42) extend in the arrangement direction of the fins (41). The plate stack (50, 60) is provided therein with refrigerant flow paths (51, 61) that communicate with the heat transfer tubes (42). The refrigerant flow paths (51, 61) are an example of flow paths (51, 61).

[0049] The fins (41) are rectangular plates having long and short sides. The thickness direction of the fins (41) corresponds to the arrangement direction of the fins (41). The fins (41) are arranged at predetermined intervals in the thickness direction. These intervals define air flow paths. The fins (41) are made of an aluminum alloy.

[0050] The heat transfer tube (42) is a straight tube. The heat transfer tubes (42) are made of an aluminum alloy. A refrigerant flow path is formed inside the heat transfer tube (42). The heat transfer tubes (42) extend parallel to one another and penetrate the fins (41). One end of the heat transfer tube (42), i.e., the right end, protrudes to the right of the rightmost fin (41) among the fins (41). The end of the heat transfer tube protruding to the right is connected to the plate stack (50, 60).

[0051] Of the left ends of the plurality of heat transfer tubes (42), the ends 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 as a single unit.

[0052] The indoor heat exchanger (40) of this embodiment has a front heat exchange section (40A) and a rear heat exchange section (40B). 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) and a second front main heat exchange section (43b). The first front main heat exchange section (43a) is located in the upper part of the front main heat exchange section (43), and the second front main heat exchange section (43b) is located in the 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)).

[0056] 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 number of heat transfer tubes (42) in the first auxiliary heat exchange section (44) in a direction along the long sides (hereinafter referred to as the number of rows) is smaller than the number of rows of the heat transfer tubes (42) in the first front main heat exchange section (43a). The number of heat transfer tubes (42) in the first auxiliary heat exchange section (44) in a direction along the short sides (hereinafter referred to as the number of rows) is smaller than the number of rows of the heat transfer tubes (42) in the first front main heat exchange section (43a).

[0057] 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 number of rows and columns of the heat transfer tubes (42) of the second auxiliary heat exchange section (45) is smaller than the number of rows and columns of the heat transfer tubes (42) of the second front main heat exchange section (43b).

[0058] The rear heat exchange section (40B) has a rear main heat exchange section (46) and a third auxiliary heat exchange section (47). The rear main heat exchange section (46) is disposed closer to the indoor fan (32) in the rear heat exchange section (40B). The third auxiliary heat exchange section (47) is provided on the inlet side (rear side) of the rear main heat exchange section (46). The lengths of the long and short sides of the fins (41) of the third auxiliary heat exchange section (47) are shorter than the lengths of the long and short sides of the fins (41) of the rear main heat exchange section (46). The number of rows and columns of the heat transfer tubes (42) of the third auxiliary heat exchange section (47) is smaller than the number of rows and columns of the heat transfer tubes (42) of the rear main heat exchange section (46).

[0059] The plate stack (50, 60) is disposed to the right of the heat exchanger body (B) and adjacent to the heat exchanger body (B). The right side is an example of a first direction. Specifically, the plate stack (50, 60) is disposed to the right of the rightmost fin (41) of the multiple fins (41) and parallel to the fin (41). The plate stack (50, 60) is connected to the ends of the heat transfer tubes (42). As shown in FIG. 5 , the plate stack (50, 60) includes a front plate stack (50) connected to the heat transfer tubes (42) of the front heat exchange section (40A) and a rear plate stack (60) connected to the heat transfer tubes (42) of the rear heat exchange section (40B). The front plate stack (50) is disposed to overlap the front heat exchange section (40A) in the axial direction of the heat transfer tubes (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 tubes (42). The front plate stack (50) and the rear plate stack (60) will be described in detail later.

[0060] (3-2) Indoor Expansion Valve, Gas Relay Pipe, and Liquid Relay Pipe The indoor expansion valve (37) is an electronic expansion valve with a variable opening. 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 is connected 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 connecting the front refrigerant flow path (51) of the front plate stack (50) and the rear refrigerant flow path (61) of the rear plate stack (60).

[0061] (4) Plate Stack The gas relay pipe (12a) transports the refrigerant gas compressed by the compressor (21) to the indoor heat exchanger (40). The gas relay pipe (12a) is an example of a gas pipe (12a). 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.

[0062] The plate stack (50, 60) has therein a flow path (51, 61) that communicates with the heat transfer tube (42). The plate stack (50, 60) is configured such that a plurality of plates (52, 62) are stacked in the rightward direction. Details of the plate stack (50, 60) of this embodiment will be described below with reference to FIGS. 5 to 14.

[0063] (4-1) Front Plate Stack The front plate stack (50) includes a front refrigerant flow path (51) formed in the front plate stack (50), a plurality of front connecting pipes (53) connecting the front refrigerant flow path (51) to the plurality of heat transfer tubes (42) of the front heat exchange section (40A), a front relay section (54) to which the first internal piping (38) is connected, and a liquid end portion (55) communicating with the second connection piping (13) via the liquid relay pipe (13a). Hereinafter, the front plate stack (50) will be described as the plate stack (50, 60) of the present disclosure.

[0064] (4-1-1) First Plate Portion and Second Plate Portion As shown in FIGS. 5, 6, and 8, the front plate stack (50) has a front first plate portion (50A) and a front second plate portion (50B). The front first plate portion (50A) has three stacked front plates (52). The front second plate portion (50B) has two stacked front plates (52). The front first plate portion (50A) constitutes the first plate portion (50A, 60A). The front second plate portion (50B) constitutes the second plate portion (50B, 60B) of the present disclosure.

[0065] The outer edges of the front plates (52) of the front first plate portion (50A) have the same shape. The three front plates (52) of the front first plate portion (50A) are, from left to right, a first plate (521), a second plate (522), and a third plate (523). A front connecting pipe (53) extending toward the right end of the heat transfer tube (42) is connected to the first plate (521). The interior of the front connecting pipe (53) defines a front refrigerant flow path (51), which will be described later.

[0066] The outer edges of the front plates (52) of the front second plate portion (50B) have the same shape. The two front plates (52) of the front second plate portion (50B) are referred to as a fourth plate (524) and a fifth plate (525) from the left.

[0067] The shape of each of the front plates (521, 522, 523) of the front first plate portion (50A) is different from the shape of each of the front plates (524, 525) of the front second plate portion (50B). Specifically, the shape of the outer edge of the front first plate portion (50A) is different from the shape of the outer edge of the front second plate portion (50B).

[0068] The front second plate portion (50B) is arranged on the surface of the front first plate portion (50A) opposite to the surface facing the heat exchanger body (B). Specifically, the front second plate portion (50B) is arranged on the right side surface of the front first plate portion (50A).

[0069] The front plates (521-525) of each of the front first plate portion (50A) and the front second plate portion (50B) are made of the same material as the heat transfer tube (42) and the front connecting pipe (53). In this embodiment, the front plates (521-525) of each of the front first plate portion (50A) and the front second plate portion (50B) are made of an aluminum alloy.

[0070] When the front plate stack (50) is viewed from the right, the area of ​​the right side surface of the front first plate portion (50A) is larger than the area of ​​the right side surface of the front second plate portion (50B). As a result, when viewed from the right of the front plate stack (50), a first region (S1) is formed in which the front first plate portion (50A) and the front second plate portion (50B) do not overlap, and a second region (S2) is formed in which the front first plate portion (50A) and the front second plate portion (50B) overlap.

[0071] When the front plate stack (50) is viewed from the right, the area of ​​the portion of the front first plate portion (50A) that is not overlapped with the front second plate portion (50B) is smaller than the area of ​​the portion that is overlapped with the front second plate portion (50B). In other words, the area of ​​the first region (S1) is smaller than the area of ​​the second region (S2).

[0072] As shown in FIG. 8 , the front plate stack (50) has a step (X). The step (X) is formed by a front first plate portion (50A) and a front second plate portion (50B). The step (X) is formed on the peripheral edge of the second surface (502) of the front plate stack (50), which is opposite to the first surface (501) facing the heat exchanger body (B). The first surface (501) is the left side surface (501) of the front plate stack (50). The second surface (502) is the right side surface (502) of the front plate stack (50). That is, the step (X) is formed on the peripheral edge of the right side surface (502) of the front plate stack (50).

[0073] The step portion (X) is a portion where the first region (S1) is formed when the front plate assembly (50) is viewed from the right. Specifically, the step portion (X) is formed by the first region (S1) and a first peripheral surface (P1) of the front second plate portion (50B). The first peripheral surface (P1) refers to a portion of the peripheral surface between the right side surface and the left side surface of the front second plate portion (50B) that contacts the first region (S1).

[0074] The step portion (X) is formed in the lower part of the front plate stack (50) when viewed from the right. Specifically, the step portion (X) is formed in the front plate stack (50) below the height position of the center of the front plate stack (50). In other words, in the air conditioning indoor unit (30) of this embodiment, the air inlet (33), the front heat exchange section (40A), and the air outlet (34) are arranged in this order from top to bottom (see FIG. 3 ), and therefore the step portion (X) is formed in the front plate stack (50, 60) at a position close to the air outlet (34).

[0075] In this way, the first region (S1) is formed below the front first plate portion (50A). The overlapping portions of the front first plate portion (50A) and the front second plate portion (50B) on the peripheral surface of the front plate stack (50) are flush with each other. In other words, when the front plate stack (50) is viewed from the left, no region is formed where the front first plate portion (50A) and the front second plate portion (50B) do not overlap.

[0076] Furthermore, the first region (S1) only needs to be formed below the front first plate portion (50A) when the front plate stack (50) is viewed from the right, and the shape of the first region (S1) is not limited.

[0077] The front plate assembly (50) is anti-corrosion treated. Specifically, the entire left side surface (501) and the second region (S2) of the right side surface (502) of the front plate assembly (50, 60) are anti-corrosion treated. In this embodiment, an alloy plate having a sacrificial anti-corrosion effect is provided on the entire left side surface (501) and the second region (S2) of the right side surface (502) of the front plate assembly (50, 60). The alloy plate is made of, for example, a clad material having an aluminum core and a metal with a relatively high zinc content as a skin material. Note that the first region (S1) and the first peripheral surface (P1) do not require anti-corrosion treatment. This is because the third plate (523) constituting the first region (S1) is a thick intermediate plate (522-524). Similarly, the fourth plate (524) constituting a part of the first peripheral surface (P1) is also one of the thick intermediate plates (522-524).

[0078] Next, the plate thickness of each of the front plates (521 to 525) of the front plate stack (50) will be described. In the front plate stack (50), the front plate of the front first plate portion (50A) closest to the heat exchanger body (B) is referred to as the first end plate (521), and the front plate of the front second plate portion (50B) farthest from the heat exchanger body (B) is referred to as the second end plate (525). In this embodiment, the first end plate (521) is the first plate (521) located at the left end of the front first plate portion (50A), and the second end plate (525) is the fifth plate (525) located at the right end of the front second plate portion (50B).

[0079] In the front plate stack 50, the plates disposed between the first end plate 521 and the second end plate 525 are referred to as intermediate plates 522 to 524. In this embodiment, the intermediate plates 522 to 524 are the second plate 522, the third plate 523, and the fourth plate 524.

[0080] The thickness of each of the intermediate plates (522-524) is greater than the thickness of the first end plate (521) and the second end plate (525). In this embodiment, the thickness of each of the intermediate plates (522-524) is 3.0 mm, and the thickness of the first end plate (521) and the second end plate (525) is 1.5 mm.

[0081] (4-1-2) Configuration of Refrigerant Channel The configuration of the front refrigerant channel (51) of the plate stack (50, 60) of this embodiment will be described. The front refrigerant channel (51) constitutes the refrigerant channel (51, 61) of the present disclosure. An example of the front refrigerant channel (51) will be described below.

[0082] 9 and 10 , the front refrigerant flow path (51) includes a first flow path (51A) provided in the front first plate portion (50A) and a second flow path (51B) provided across the front first plate portion (50A) and the front second plate portion (50B). The first flow path (51A) and the second flow path (51B) are provided in a portion overlapping with the front first plate portion (50A) and the front second plate portion (50B).

[0083] The first flow path (51A) is composed of two first through holes (71) passing through the first plate (521) located at the left end of the front first plate portion (50A) in the thickness direction, a first groove (81) formed in the second plate (522) located in the center, and a third plate (523) located at the right end. One end of the first through hole (71) communicates with one end of the heat transfer tube (42). The other end of the first through hole (71) is connected to the first groove (81).

[0084] The first groove (81) is an elongated hole formed along the surface of the first plate (521). One end of the first groove (81) is connected to one of the first through holes (71), and the other end of the first groove (81) is connected to the other first through hole (71). The first groove (81) is blocked from the left and right directions by the first plate (521) located at the left end and the first plate (521) located at the right end.

[0085] The second flow path (51B) is configured by a second through-hole (72) penetrating the front first plate portion (50A) in the thickness direction, a second groove (82) formed in a fourth plate (524) located at the left end of the front second plate portion (50B), and a fifth plate (525) located at the right end of the front second plate portion (50B). One end of the second through-hole (72) communicates with one end of the heat transfer tube (42). The other end of the second through-hole (72) is connected to the second groove (82). The second groove (82) is an elongated hole formed along the surface of the second plate (522). One end of the second groove (82) is connected to one of the second through-holes (72), and the other end of the second groove (82) is connected to the other of the second through-holes (72). The second groove (82) is closed from the left and right by the third plate (523) and the fifth plate (525).

[0086] 11 , the first groove (81) and the second groove (82) are arranged to intersect with each other when the front plate stack (50) is viewed from the right. This causes the second flow path (51B) to intersect with the first flow path (51A). Specifically, the second flow path (51B) is formed to straddle the first flow path (51A) to the right.

[0087] As shown in FIG. 12 , the front refrigerant flow path (51) has a third flow path (51C) formed in a portion of the front first plate portion (50A) that does not overlap with the front second plate portion (50B). Specifically, when the front plate stack (50) is viewed from the right, the third flow path (51C) is formed in the first region (S1). The third flow path (51C) is composed of two third through holes (73) that penetrate the first plate (521) of the front first plate portion (50A) in the thickness direction, a third groove (83) formed in the second plate (522), and the third plate (523). One end of the third through hole (73) communicates with one end of the heat transfer tube (42). The other end of the third through hole (73) connects to the third groove (83). The third groove (83) is an elongated hole formed along the surface of the second plate (522). One end of the third groove portion (83) is connected to one of the third through holes (73), and the other end of the third groove portion (83) is connected to the other of the third through holes (73). The third groove portion (83) is closed from the left and right directions by the first plate (521) and the third plate (523).

[0088] 6, the rear plate stack (60) includes a rear refrigerant flow path (61) formed inside the rear plate stack (60), a plurality of rear connecting pipes (not shown) connecting the heat transfer tubes (42) of the rear heat exchange section (40B) to the rear refrigerant flow path (61), a rear relay section (64) to which the second internal piping (39) is connected, and a gas end portion (65) communicating with the first connection piping (12) via the gas relay pipe (12a). The rear refrigerant flow path (61) constitutes the refrigerant flow path (51, 61) of the present disclosure.

[0089] The rear plate stack (60) differs from the front plate stack (50) in the shape of the outer edges of the plates as viewed from the right and in the rear refrigerant flow paths (61) therein. The rear plate stack (60) is a thick plate-like member formed by stacking five rear plates (62) of the same shape. The rear plates (62) are stacked in the right direction.

[0090] The five rear plates (62) constituting the rear plate stack (60) are, from left to right, a sixth plate (621), a seventh plate (622), an eighth plate (623), a ninth plate (624), and a tenth plate (625) (see Figure 5).

[0091] As with the front plate stack (50, 60), the sixth plate (621) closest to the heat exchange section (B) is the first end plate (621), the tenth plate (625) farthest from the heat exchange section (B) is the second end plate (625), and the seventh to ninth plates (622 to 624) arranged between the sixth plate (621) and the tenth plate (625) are the intermediate plates (622 to 624). In this case, the thickness of each of the intermediate plates (622 to 624) is greater than the thickness of the sixth plate (621) and the tenth plate (625).

[0092] The rear plate assembly (50, 60) is subjected to the same corrosion prevention treatment as the front plate assembly (50, 60). Specifically, the alloy plates are attached to the left side surface (601) and the right side surface (602) of the rear plate assembly (60). The left side surface (601) and the right side surface (602) of the rear plate assembly (60) correspond to the first surface (601) and the second surface (602) of the present disclosure, respectively.

[0093] The rear relay portion (64) is a circular pipe. As shown in FIG. 6 , the rear relay portion (64) is disposed on the right side surface of the rear plate stack (60). That is, in the rear plate stack (60), the second internal pipe (39) connecting the front refrigerant flow path (51) of the front plate stack (50) and the rear refrigerant flow path (61) of the rear plate stack (60) is connected to the right side surface of the rear plate stack (60). The gas end portion (65) is a circular pipe. The gas end portion (65) is disposed on the right side surface of the rear plate stack (60).

[0094] (5) Arrangement of Partition Plate and Electrical Component Box As shown in Fig. 8 , the air conditioning indoor unit (30) of this embodiment is provided with a partition plate (100) in the casing (31). The partition plate (100) is a plate-like member that separates the indoor heat exchanger (40) from the electrical component box (200).

[0095] The electrical component box (200) is disposed to the right of the indoor heat exchanger (40). The electrical component box (200) faces the step portion (X) to the right. The partition plate (100) is disposed between the indoor heat exchanger (40) and the electrical component box (200). The electrical component box (200) is an example of a second component (200). The electrical component box (200) accommodates electrical components including predetermined circuit boards.

[0096] The partition plate (100) extends in the vertical direction between the indoor heat exchanger (40) and the electrical component box (200). The partition plate (100) has a first plate portion (100A), a second plate portion (100B), and a third plate portion (100C). The second plate portion (100B) is connected to the lower end of the first plate portion (100A), and the third plate portion (100C) is connected to the lower end of the second plate portion (100B). The partition plate (100) has a recess (101) formed therein.

[0097] The first plate portion (100A) extends in a generally vertical direction. The height position of the lower end of the first plate portion (100A) is the same as the height position of the upper end of the step portion (X). In other words, the height position of the lower end of the first plate portion (100A) is the same as the height position of the lower end of the front second plate portion (50B). The second plate portion (100B) extends leftward from the lower end of the first plate portion (100A). In other words, the second plate portion (100B) extends leftward from the lower end of the first plate portion (100A) so as to approach the space formed by the step portion (X). Here, the space formed by the step portion (X) refers to a space that would not be formed in the front plate stack (50) of this embodiment if the front first plate portion (50A) and the front second plate portion (50B) have the same shape and the step portion (X) is not formed. The lower end of the second plate portion (100B) extends to the lower end of the front plate stack (50). The third plate portion (100C) extends downward substantially perpendicularly from the lower end of the second plate portion (100B). The recess (101) is a space formed by the second plate portion (100B) and the third plate portion (100C).

[0098] The electrical component box (200) is disposed near the partition plate (100). The electrical component box (200) is disposed to the right of the second plate portion (100B). The electrical component box (200) is disposed as close as possible to the second plate portion (100B). In this state, the upper end of the electrical component box (200) is located directly below the lower end of the first plate portion (100A). In this manner, the electrical component box can be disposed further to the left than if the partition plate (100) did not have the second plate portion (100B) and only had the first plate portion (100A).

[0099] (6) Features (6-1) Feature 1 The front plate stack (50) of the plate stack (50, 60) of the indoor heat exchanger (40) of this embodiment is disposed adjacent to the heat exchanger body (B) in the right direction (first direction). The front plate stack (50) includes a front first plate portion (50A) having three plates (52) and a front second plate portion (50B) having two plates (52) and disposed on the surface of the front first plate portion (50A) opposite to the surface facing the indoor heat exchanger (40). A step (X) is formed in the peripheral edge of the right side surface (502) of the front plate stack (50), which is the surface opposite to the left side surface (501) facing the heat exchange portion (B). The step (X) is formed by the front first plate portion (50A) and the front second plate portion (50B).

[0100] In this way, by providing the step portion (X) in the front plate stack (50), a space can be formed at a position opposite the step portion (X). By utilizing this space, for example, by arranging predetermined components in the space, the air conditioning indoor unit (30) can be made smaller.

[0101] (6-2) Feature 2 The air conditioning indoor unit (30) of this embodiment further includes an electrical component box (200) (second component) adjacent to the indoor heat exchanger (40) and facing the stepped portion (X) to the right (first direction), and a partition plate (100) disposed between the indoor heat exchanger (40) and the electrical component box (200). The partition plate (100) has a recess (101) formed to follow the shape of the stepped portion (X).

[0102] The partition plate (100) has a recess (101) formed so as to be recessed toward the step (X), thereby making it possible to effectively utilize the space formed by the recess (101). By arranging the electrical component box (200) in the space formed by the recess (101), the length of the casing (31) in the left-right direction can be shortened, thereby realizing a compact air conditioning indoor unit (30).

[0103] (6-3) Feature 3 In this embodiment, the second to fourth plates (522 to 524) of the front plate stack (50) are thicker than the first plate (521) and the fifth plate (525), and the seventh to ninth plates (622 to 624) of the rear plate stack (60) are thicker than the sixth plate (621) and the tenth plate (625).

[0104] Increasing the thickness of each of the intermediate plates (522-524, 622-624) in this way makes it possible to increase the cross-sectional area or inner diameter of the refrigerant flow paths (51, 61) formed in the plate stack (50, 60), thereby suppressing an increase in pressure loss of the refrigerant flowing through the refrigerant flow paths (51, 61).

[0105] (6-4) Feature 4 In the present embodiment, the second regions (S2) of the left side surface (501) and the right side surface (502) of the front plate stack (50) and the left side surface (601) and the right side surface (602) of the rear plate stack (60) are anticorrosive treated. This makes it possible to prevent electrolytic corrosion of the side surfaces of the plate stacks (50, 60) due to condensation or the like, thereby improving the durability of the indoor heat exchanger (40).

[0106] (6-5) Feature 5 In the front plate stack (50) of this embodiment, when the front plate stack (50) is viewed from the right, the area of ​​the portion of the front first plate portion (50A) that is not overlapped by the front second plate portion (50B) is smaller than the area of ​​the portion that is overlapped by the front second plate portion (50B).

[0107] In the front plate stack (50), the portion where the front first plate portion (50A) and the front second plate portion (50B) are stacked is thicker than the front first plate portion (50A) alone, which ensures a corresponding number of front refrigerant flow paths (51). That is, since the area of ​​the first region (S1) is smaller than the area of ​​the second region (S2), it is possible to ensure a sufficient number of front refrigerant flow paths (51) in the front plate stack (50), thereby facilitating heat exchange between the air and the refrigerant in the indoor heat exchanger (40).

[0108] (6-6) Feature 6 In this embodiment, the front refrigerant flow path (51) formed in the front plate stack (50) includes a first flow path (51A) provided only in the front first plate portion (50A) and a second flow path (51B) provided across the front first plate portion (50A) and the front second plate portion (50B). The first flow path (51A) and the second flow path (51B) are formed to intersect with each other.

[0109] Designing the front refrigerant flow path (51) so that the first flow path (51A) and the second flow path (51B) intersect increases the variety of flow path patterns of the front refrigerant flow path (51) in the front plate stack (50). On the other hand, by providing only the first flow path (51A) in the front plate stack (50) and using a step portion (X) as a portion where the first flow path (51A) and the second flow path (51B) do not intersect, it is possible to form an effectively usable space and reduce unnecessary portions of the plates where the front refrigerant flow path (51) is not provided.

[0110] (7) Modifications A description will be given of a modification of the air conditioner indoor unit (30). The following describes configurations that differ from the air conditioner indoor unit (30) of the above embodiment.

[0111] The rear plate stack (60) of the modified example has the same configuration as the front plate stack (50) of the above embodiment. That is, the rear plate stack (60) has a rear first plate portion (60A) and a rear second plate portion (60B). The rear first plate portion (60A) and the rear second plate portion (60B) are included in the first plate portion (50A, 60A) and the second plate portion (50B, 60B) of the present disclosure. The rear plate stack (60) constitutes the plate stack (50, 60) of the present disclosure. The configurations of the rear first plate portion (60A) and the rear second plate portion (60B) are the same as the configurations of the front first plate portion (50A) and the front second plate portion (50B) of the front plate stack (50) of the above embodiment, respectively, and therefore will not be described.

[0112] 13 and 14 , the gas end portion (65) formed in the rear plate stack (60) is connected to a rear refrigerant flow path (61) formed in a portion of the rear plate stack (60) where the rear first plate portion (60A) and the rear second plate portion (60B) overlap. Specifically, the gas end portion (65) is located in the second region (S2). More specifically, the gas end portion (65) is provided at one end of the rear refrigerant flow path (61) formed across the rear first plate portion (60A) and the rear second plate portion (60B).

[0113] As a result, the gas refrigerant flowing in from the gas relay pipe (12a) through the gas end (65) flows from the rear second plate portion (60B) to the rear first plate portion (60A) of the rear plate stack (60). Among the rear refrigerant flow paths (61) extending in the stacking direction of the rear plate stack (60), the rear refrigerant flow path (61) extending from the rear first plate portion (60A) to the rear second plate portion (60B) has a longer flow path length than the rear refrigerant flow path (61) formed only in the rear first plate portion (60A). In this manner, in this modification, the gas end (65) is located in the second region (S2), thereby reducing pressure loss of the refrigerant gas passing through the rear refrigerant flow path (61) in the rear plate stack (60).

[0114] (8) Other Embodiments The following configurations may be applied to the air conditioner indoor unit (30) of the above embodiment and the above modified examples.

[0115] As shown in FIG. 15 , at least a portion of the functional components (300) disposed within the casing (31) may be disposed facing the step portion (X) to the right. In this case, the partition plate (100) need not be provided. The functional components (300) may be any component necessary for the air conditioning indoor unit (30) and may be an electrical component box. The functional components (300) are an example of the first component (300). While a predetermined gap is formed between the adjacent functional components (300) and the front plate stack (50), the space formed by the step portion (X) can be effectively utilized to position the functional components (300) closer to the front plate stack (50). In other words, the functional components (300) can be positioned further to the left, thereby reducing the size of the casing (31) in the left-right direction.

[0116] As shown in FIG. 16 , when the plate stack (50, 60) is viewed from the right, the functional component (300) disposed in the casing (31) is disposed closer to the step (X) than the end of the front second plate (50B) that constitutes the step (X). Specifically, the step (X) is formed in the lower part of the front plate stack (50), and therefore the height position of the end of the front second plate (50B) that constitutes the step (X) is located at the lower end of the front second plate (50B). Therefore, the functional component (300) adjacent to the right side of the front plate stack (50) is disposed below the lower end of the front second plate (50B). More precisely, the functional component (300) is located opposite the step (X) in the right direction and below the lower end of the front second plate (50B). The functional part (300) is an example of the first part (300).

[0117] Because the upper end of the functional component (300) is positioned lower than the lower end of the front second plate portion (50B), a portion of the functional component (300) can be disposed in the space defined by the step (X). That is, at least a portion of the functional component (300) can be disposed inside the step (X). In other words, the functional component (300) is disposed at a predetermined distance from the front plate assembly (50). Disposing the functional component (300) below the lower end of the front second plate portion (50B) allows the functional component (300) to be disposed closer to the front plate assembly (50) than disposing it above the lower end of the front second plate portion (50B). This shortens the casing (31) in the left-right direction, thereby enabling the air conditioning indoor unit (30) to be more compact. Even in this case, the partition plate (100) need not be provided. The functional component (300) may be any component necessary for the air conditioning indoor unit (30), and may be an electrical component box.

[0118] As shown in FIG. 17 , at least a portion of the functional component (300) disposed in the casing (31) is disposed within the step portion (X). Specifically, at least a portion of the functional component (300) is disposed in the space defined by the step portion (X). That is, when the air conditioning indoor unit (30) is viewed from above, at least a portion of the functional component (300) is recessed toward the plate stack (50, 60). This allows the casing (31) to be shorter in the left-right direction than when the functional component (300) is disposed outside the step portion (X). Note that, even in this case, the partition plate (100) does not necessarily have to be provided. The functional component (300) may be any component necessary for the air conditioning indoor unit (30), and may be an electrical component box.

[0119] As shown in FIG. 18 , a U-shaped connecting pipe (400) may be provided in the step portion (X) of the front plate laminate (50). The U-shaped connecting pipe (400) is in communication with the front refrigerant flow path (51) in the front plate laminate (50). Specifically, the U-shaped connecting pipe (400) is disposed in the first region (S1), and both ends of the U-shaped connecting pipe are connected to the first region (S1). A temperature sensor (not shown) for measuring the temperature of the refrigerant flowing through the front refrigerant flow path (51) is attached to the U-shaped connecting pipe (400), for example. By providing the U-shaped connecting pipe (400) in the step portion (X) in this manner, the horizontal length of the indoor heat exchanger (40) can be reduced compared to providing the U-shaped connecting pipe (400) in the second region (S2).

[0120] In the above embodiment, the indoor heat exchanger (40) may be configured so that refrigerant in the supercooled region flows through the third flow path (51C) formed in the front plate stack (50) when the indoor heat exchanger (40) functions as a radiator. In this case, the liquid end portion (55) may be disposed in the first region (S1) so as to communicate with the third flow path (51C). Unlike the first flow path (51A) and the second flow path (51B), the third flow path (51C) is not configured to intersect with other front refrigerant flow paths (51). Therefore, the third flow path (51C) can be disposed away from the other front refrigerant flow paths (51). In other words, because the third flow path (51C) is not disposed near the other front refrigerant flow paths (51), heat exchange between the refrigerant in the supercooled region flowing through the third flow path (51C) and the refrigerant flowing through the other front refrigerant flow paths (51) can be suppressed.

[0121] The indoor heat exchanger (40) is arranged in an air passage (P) that communicates with an inlet (33) and an outlet (34) provided in the casing (31), and the step portion (X) may be formed downstream of the air flow in the plate stack (50, 60) when viewed from the right.

[0122] For example, in summer, when the indoor heat exchanger (40) functions as an evaporator, a temperature gradient is formed in the air passage (P) such that the temperature decreases from the inlet (33) to the outlet (34). Because the air temperature increases upstream in the air passage (P), the heat exchange load is greater in the upstream portion of the indoor heat exchanger (40) than in the downstream portion of the air flow. Therefore, by providing the step (X) in the downstream portion of the plate stack (50, 60) and thickening the upstream portion of the plate stack (50, 60), a sufficient number of refrigerant flow paths (51, 61) can be ensured in the upstream portion of the plate stack (50, 60). This increases the flow rate of refrigerant flowing to the upper portion of the heat exchanger body (B), thereby facilitating heat exchange between the refrigerant and air in the upper portion of the indoor heat exchanger (40). As a result, the heat exchange load at the upper part of the indoor heat exchanger (40) can be reduced, and the efficiency of heat exchange with the air flowing through the air passage (P) can be increased, so that the air temperature in the indoor space can be quickly raised to the target temperature.

[0123] In the above embodiment, a liquid end portion (55) may be formed in the step portion (X) of the front plate stack (50). Specifically, the liquid end portion (55) may be located in the first region (S1) of the front plate stack (50). This prevents the liquid relay pipe (13a) extending rightward from the liquid end portion (55) from protruding to the right, thereby reducing the length of the indoor heat exchanger (40) in the left-right direction. This allows the air conditioner indoor unit (30) to be made more compact.

[0124] In the above embodiment, a front relay portion (54) may be formed in the step portion (X) of the front plate stack (50). Specifically, the front relay portion (54) may be disposed in the first region (S1) of the front plate stack (50). This reduces the rightward protrusion of the first internal pipe (38) extending rightward from the front relay portion (54), thereby reducing the left-right length of the indoor heat exchanger (40). This allows the air conditioning indoor unit (30) to be made more compact.

[0125] In the above-described modified example, a rear relay portion (64) may be formed in the step portion (X) of the rear plate stack (60). Specifically, the rear relay portion (64) may be disposed in the first region (S1) of the rear plate stack (60). This can prevent the second internal pipe (39) extending rightward from the rear relay portion (64) from protruding to the right, thereby reducing the length of the indoor heat exchanger (40) in the left-right direction. This allows the air conditioning indoor unit (30) to be made more compact.

[0126] In the above modification, the rear plate stack (60) may be formed with rear refrigerant flow paths (61) corresponding to the first flow paths (51A) and the second flow paths (51B) of the front plate stack (50) of the above embodiment. In other words, the rear plate stack (50, 60) may be configured such that a plurality of rear refrigerant flow paths (61) intersect with each other.

[0127] In the above modification, the rear plate stack (60) may be provided with a rear refrigerant flow path (61) corresponding to the third flow path (51C) of the above embodiment. That is, the rear refrigerant flow path (61) may be provided in a portion of the rear first plate portion (60A) where the rear first plate portion (60A) and the rear second plate portion (60B) do not overlap. This rear refrigerant flow path (61) is referred to as a rear third flow path. When the indoor heat exchanger (40) functions as an evaporator, the indoor heat exchanger (40) may be configured so that refrigerant in a superheated region flows through the rear third flow path. In this case, a gas end portion (65) may be provided in the first region (S1), and the gas end portion (65) may be configured to communicate with the rear third flow path. The rear third flow path can be located away from the other rear refrigerant flow paths (61), thereby preventing refrigerant in a superheated region from exchanging heat with refrigerant in the other rear refrigerant flow paths (61).

[0128] In the above embodiment and modified examples, the first plate portion (50A, 60A) or the second plate portion (50B, 60B) may have one or more plates. That is, the first plate portion (50A, 60A) may have three or more plates, and the second plate portion (50B, 60B) may have two or more plates.

[0129] The front refrigerant flow path (51) formed only in the front first plate portion (50A) like the above-described third flow path (51C) may be formed up to the right end of the front first plate portion (50A). Specifically, the third groove portion (83) may be formed in a plate disposed adjacent to the plate disposed at the right end (first direction end) of the front first plate portion (50A).

[0130] The plate stack (50, 60) may have, in addition to the first plate portion (50A, 60A) and the second plate portion (50B, 60B), a third plate portion different from the first plate portion (50A, 60A) and the second plate portion (50B, 60B). The third plate portion may be stacked on the right end of the second plate portion (50B, 60B), and a new step portion may be formed by the second plate portion (50B, 60B) and the third plate portion when viewed from the right.

[0131] In the above embodiment and modified examples, instead of using alloy plates having a sacrificial corrosion protection effect, anticorrosive or antirust paint may be applied to the plate stack (50, 60). In this case, the paint is an epoxy resin-based paint. The paint may be applied so that a coating film is formed on the front surface, including the right side surface (502) and the left side surface (501) of the plate stack (50, 60).

[0132] The heat transfer tubes (42), the plate stacks (50, 60), or the refrigerant piping (such as the connecting pipe (53) and the U-shaped connecting pipe (400)) may be made of a copper alloy or stainless steel. When the heat transfer tubes (42) are made of a copper alloy, the plate stacks (50, 60) and the refrigerant piping are preferably made of a copper alloy as well.

[0133] Although the embodiments and modifications have been described above, it will be understood that various modifications in form and detail are possible without departing from the spirit and scope of the claims. Furthermore, the above embodiments and modifications may be combined or substituted as appropriate as long as the functionality of the subject matter of the present disclosure is not impaired. The terms "first," "second," etc., described above, are used to distinguish the terms to which these terms are attached, and do not limit the number or order of the terms.

[0134] INDUSTRIAL APPLICABILITY As described above, the present disclosure is useful for indoor heat exchangers and air conditioning indoor units.

[0135] 12a Gas relay pipe (gas pipe) 30 Air conditioner indoor unit 31 Casing 33 Intake port 40 Indoor heat exchanger 41 Fin 42 Heat transfer pipe 50, 60 Plate stack 50A First plate portion 50B Second plate portion 51, 61 Flow path (refrigerant flow path) 51A First flow path 51B Second flow path 51C Third flow path 52, 62 Plate 100 Partition plate 101 Recess 200 Second part (electrical equipment box) 300 Functional part (first part) 521 First end plate 522 Second plate 522~524 Intermediate plates 525 Fifth plate (second end plate) B Heat exchanger body (heat exchange section) P Air passage X Step section

Claims

1. A heat exchanger (B) including a plurality of fins (41) and a plurality of heat transfer tubes (42) penetrating the plurality of fins (41); and a plate stack (50, 60) having a flow path (51, 61) therein communicating with the heat transfer tubes (42) and including a plurality of plates (52, 62) stacked in a first direction in which the heat transfer tubes (42) extend, the plate stack (50, 60) comprising: a first plate portion (50A, 60A) disposed adjacent to the heat exchanger (B) in the first direction and having one or more of the plates (52, 62); an indoor heat exchanger comprising: one or more plates (52, 62) having a shape different from that of the plates (52, 62) of the first plate portion (50A, 60A); and a second plate portion (50B, 60B) arranged on a surface of the first plate portion (50A, 60A) opposite to a surface facing the heat exchange portion (B); a step portion (X) is formed in a peripheral portion of a second surface (502, 602) of the plate stack (50, 60) opposite to a first surface (501, 601) facing the heat exchange portion (B), and the step portion (X) is formed by the first plate portion (50A, 60A) and the second plate portion (50B, 60B).

2. An air-conditioning indoor unit comprising: the indoor heat exchanger according to claim 1; a casing (31) that houses the indoor heat exchanger; and a first component (300) that is arranged in the casing (31), wherein at least a part of the first component (300) is arranged to face the step portion (X) in the first direction.

3. The air conditioning indoor unit according to claim 2, wherein, when the plate stack (50, 60) is viewed from the first direction, the first component (300) is positioned closer to the step portion (X) than an end of the second plate portion (50B, 60B) that constitutes the step portion (X).

4. The air conditioning indoor unit according to claim 2, wherein at least a portion of the first component (300) is disposed inside the step portion (X).

5. The air-conditioning indoor unit according to claim 2, further comprising: a second component (200) adjacent to the indoor heat exchanger (40) and facing the stepped portion (X) in the first direction; and a partition plate (100) arranged between the indoor heat exchanger (40) and the second component (200), wherein the partition plate (100) has a recess (101) formed to follow the shape of the stepped portion (X).

6. The air conditioning indoor unit as claimed in any one of claims 2 to 5, wherein an air passage (P) is formed in the casing (31) through which air flows from an inlet (33) formed in the casing (31) toward an outlet (34), the indoor heat exchanger (40) is disposed in the air passage (P), and the stepped portion (X) is formed in a portion of the plate stack (50, 60) closer to the downstream side of the air flow as viewed from the first direction.

7. The plate stack (50, 60) is composed of three or more of the plates (52, 62), and when, in the plate stack (50, 60), the plate (52, 62) of the first plate portion (50A, 60A) closest to the heat exchange portion (B) is defined as a first end plate (521, 621), the plate (52, 62) of the second plate portion (50B, 60B) farthest from the heat exchange portion (B) is defined as a second end plate (525, 625), and the plate (52, 62) disposed between the first end plate (521, 621) and the second end plate (525, 625) is defined as an intermediate plate (522-524, 622-624), the flow path (51, 61) is formed to pass through the intermediate plate (522-524, 622-624), The air conditioning indoor unit according to any one of claims 2 to 6, wherein a plate thickness of the intermediate plates (522 to 524, 622 to 624) is greater than a plate thickness of the first end plate (521, 621) and the second end plate (525, 625).

8. The air conditioning indoor unit according to any one of claims 2 to 7, wherein at least a portion of the first surface (501, 601) and the second surface (502, 602) of the plate stack (50, 60) is subjected to anti-corrosion treatment.

9. An air conditioning indoor unit as described in any one of claims 2 to 8, wherein, when viewing the plate stack (50, 60) from the first direction, an area of ​​a portion of the first plate portion (50A, 60A) that is not overlapped by the second plate portion (50B, 60B) is smaller than an area of ​​a portion where the second plate portion (50B, 60B) overlaps.

10. An air conditioning indoor unit as described in any one of claims 2 to 9, wherein the flow path (51, 61) has a first flow path (51A) provided in the first plate portion (50A, 60A) and a second flow path (51B) provided across the first plate portion (50A, 60A) and the second plate portion (50B, 60B), and the second flow path (51B) is formed so as to intersect with the first flow path (51A).

11. An air conditioning indoor unit as described in any one of claims 2 to 10, wherein the flow path (51, 61) has a third flow path (51C) formed in a portion of the first plate portion (50A, 60A) that does not overlap with the second plate portion (50B, 60B) when the plate stack (50, 60) is viewed from the first direction, and a refrigerant in a superheated region flows through the third flow path (51C) when the indoor heat exchanger functions as an evaporator, and a refrigerant in a subcooled region flows through the third flow path (51C) when the indoor heat exchanger functions as a radiator.

12. An air conditioning indoor unit as described in any one of claims 2 to 11, further comprising a gas pipe (12a) that transports compressed refrigerant gas to the indoor heat exchanger (40), the gas pipe (12a) being connected to the flow path (51, 61) formed in a portion of the plate stack (50, 60) where the first plate portion (50A, 60A) and the second plate portion (50B, 60B) overlap.

Images