Indoor heat exchanger and air conditioner

Abstract

The present invention suppresses enlargement of a plate laminate. In an indoor heat exchanger, some of a plurality of heat transfer tubes (12) (heat transfer tubes (121a, 122a), etc.) are connected via a refrigerant flow path (22m) of a U-shaped elbow (22) or a refrigerant flow path of a connection pipe, and the remaining heat transfer tubes (12) are connected via a refrigerant flow path (30m) of a plate laminate (30).

Description

Technical Field

[0001] The present disclosure relates to an indoor heat exchanger and an air conditioner including the indoor heat exchanger. Background Art

[0002] Patent Document 1 discloses an indoor unit for air conditioning used in an air conditioner. In this indoor unit for air conditioning, a plate-shaped distribution member formed by stacking a plurality of plates is connected to a heat transfer tube of a heat exchanger body in order to save space.

[0003] Prior art literature

[0004] Patent Literature

[0005] Patent Document 1: Japanese Patent Application Publication No. 2006-125652 Summary of the invention

[0006] Problems to be solved by the invention

[0007] All heat transfer tubes of the heat exchanger body are connected to the plate-like distributing member in Patent Document 1. In this case, the plate-like distributing member (equivalent to the "plate stack" of the present disclosure) becomes large-sized due to the structure of the refrigerant flow path formed in the plate-like distributing member.

[0008] An object of the present disclosure is to provide an indoor heat exchanger capable of suppressing an increase in the size of a plate stack and an air conditioner including the indoor heat exchanger.

[0009] Means for solving problems

[0010] The indoor heat exchanger of the first aspect of the present disclosure comprises: a heat exchange portion, which includes fins and a plurality of heat transfer tubes passing through the fins; a refrigerant tube, which forms a first refrigerant flow path; and a plate stack, which includes a plurality of plates stacked in a stacking direction and forms a second refrigerant flow path, the plurality of heat transfer tubes include a first heat transfer tube, a second heat transfer tube, a third heat transfer tube and a fourth heat transfer tube, the first heat transfer tube is connected to the second heat transfer tube via the first refrigerant flow path, and the third heat transfer tube is connected to the fourth heat transfer tube via the second refrigerant flow path.

[0011] According to the first aspect of the present disclosure, instead of connecting all the first to fourth heat transfer tubes via the second refrigerant flow path of the plate stack, the first heat transfer tube and the second heat transfer tube are connected via the first refrigerant flow path of the refrigerant tube, and the third heat transfer tube and the fourth heat transfer tube are connected via the second refrigerant flow path of the plate stack. This can prevent the plate stack from becoming larger.

[0012] The indoor heat exchanger according to the second aspect of the present disclosure may be such that, in the first aspect, the refrigerant tube is a U-shaped bent tube, and the first heat transfer tube and the second heat transfer tube are adjacent to each other. In this case, the structure can be simplified.

[0013] The indoor heat exchanger of the third viewpoint of the present disclosure may be that in the above-mentioned first or second viewpoint, the refrigerant pipe is a U-shaped bend pipe, the temperature of the first refrigerant flowing in the first refrigerant flow path is a first temperature, and the temperature of the second refrigerant flowing in the second refrigerant flow path is a second temperature whose difference from the first temperature is greater than a specified value. Assuming that the first refrigerant and the second refrigerant with a temperature difference greater than the specified value flow in the second refrigerant flow path, heat exchange between the first refrigerant and the second refrigerant will occur in the plate stack, which may cause a large heat loss. In this regard, in the present structure, the first refrigerant flows in the first refrigerant flow path of the U-shaped bend pipe, and the second refrigerant flows in the second refrigerant flow path of the plate stack. As a result, heat exchange between the first refrigerant and the second refrigerant does not occur in the plate stack, and a large heat loss does not occur.

[0014] The indoor heat exchanger of the fourth aspect of the present disclosure may be that, in the third aspect, the first refrigerant is one of a liquid-phase refrigerant and a gas-phase refrigerant, and the second refrigerant is a gas-liquid two-layer refrigerant. The temperature of the liquid-phase refrigerant is lower than that of the gas-liquid two-layer refrigerant, and the temperature of the gas-phase refrigerant is higher than that of the gas-liquid two-layer refrigerant. In this structure, a structure in which heat exchange between the first refrigerant and the second refrigerant is not generated in the plate stack can be effectively realized.

[0015] The indoor heat exchanger of the fifth aspect of the present disclosure may be such that, in any of the first to fourth aspects, a first distance in the stacking direction from the end faces of the plurality of heat transfer tubes to the surface closest to the end faces in the plate stack is shorter than a second distance in the stacking direction from the end faces to the surface farthest from the end faces in the refrigerant tube. In this case, by arranging the plate stack and the refrigerant tube so as to overlap when viewed from the side, space can be effectively utilized.

[0016] The indoor heat exchanger according to a sixth aspect of the present disclosure may be such that, in the fifth aspect, the refrigerant pipe is arranged at a position corresponding to a recessed portion provided on the outer periphery of the plate stack. In this case, the plate stack can be made smaller and lighter.

[0017] The indoor heat exchanger of the seventh aspect of the present disclosure may be, in any one of the first to sixth aspects, the first heat transfer tube is connected to the functional component via the first refrigerant flow path. In this case, the existing structure can be used for the connection portion between the functional component and the heat transfer tube.

[0018] The indoor heat exchanger according to an eighth aspect of the present disclosure may be, in the seventh aspect, wherein the functional component is an expansion valve.

[0019] The indoor heat exchanger of the 9th aspect of the present disclosure may be, in any one of the above-mentioned 1st to 8th aspects, the heat exchange part includes a 1st heat exchange part and a 2nd heat exchange part, the 1st heat exchange part has the 1st heat transfer tube, and the 2nd heat exchange part has the 2nd heat transfer tube. If the 1st heat transfer tube of the 1st heat exchange part and the 1st heat transfer tube of the 2nd heat exchange part are connected via a plate stack, it is necessary to provide a detour circuit in the 2nd refrigerant flow path of the plate stack, so that the structure may be complicated. In this regard, in the present structure, this problem can be suppressed.

[0020] The indoor heat exchanger of the 10th aspect of the present disclosure may be, in any one of the above-mentioned 1st to 9th aspects, the indoor heat exchanger further comprises a connection portion connecting the plate stack with at least one of the third heat transfer tube and the fourth heat transfer tube in the stacking direction, and the length of the connection portion in the stacking direction is longer than the length of the refrigerant tube in the stacking direction. Since the second refrigerant flow path of the plate stack is composed of the through hole or groove of the plate, it is easy to form a corner, so that the pressure loss at the corner may increase. In order to suppress the increase in pressure loss, it is preferred to connect the heat transfer tube to the first refrigerant flow path of the refrigerant tube that is difficult to form a corner. In this regard, in this structure, since the length of the connection portion is longer than the length of the refrigerant tube, the refrigerant tube can be arranged between the heat transfer tube and the plate stack without cutting off the portion overlapping with the refrigerant tube in the plate stack. Therefore, it is easy to adopt a structure that connects the heat transfer tube to the first refrigerant flow path of the refrigerant tube. Therefore, by adopting a structure in which the heat transfer tube and the first refrigerant flow path of the refrigerant tube are connected, it is possible to suppress an increase in pressure loss.

[0021] The indoor heat exchanger of the 11th aspect of the present disclosure may be, in any one of the above-mentioned 1st to 10th aspects, the plurality of plates include: a first plate; and a second plate, which is stacked in the stacking direction at a position farther from the plurality of heat transfer tubes than the first plate, and the second refrigerant flow path includes: a first flow path formed in the first plate; and a second flow path, which is formed in both the first plate and the second plate and intersects with the first flow path when viewed from the stacking direction. In this case, instead of providing a detour in the plane of the plate, the first flow path and the second flow path are intersected, thereby suppressing the enlargement of the plate stack in the surface direction along the plane of the plate.

[0022] An air conditioner according to a twelfth aspect of the present disclosure includes the indoor heat exchanger according to any one of the first to eleventh aspects. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 It is a front view of the air conditioner according to the first embodiment of the present disclosure, in a state where the exterior panel is removed.

[0024] Figure 2 yes Figure 1 A right side view of an indoor heat exchanger included in the air conditioner is shown.

[0025] Figure 3 yes Figure 1 A perspective view of the plate stack shown.

[0026] Figure 4 It is composed Figure 3 The plan view of the leftmost plate of the five plates in the plate stack shown.

[0027] Figure 5 It is composed Figure 3 A top view of the second plate from the left of the five plates in the plate stack shown.

[0028] Figure 6 It is composed Figure 3 A top view of the third plate from the left of the five plates in the plate stack shown.

[0029] Figure 7 It is composed Figure 3 A top view of the fourth plate from the left of the five plates in the plate stack shown.

[0030] Figure 8 It is composed Figure 3 A plan view of the rightmost plate of the five plates in the plate stack shown.

[0031] Fig. 9 It is along Figure 5 A cross-sectional view of the plate stack taken along line IX-IX is shown.

[0032] Fig.10 It is a diagram showing a plate stack, a connection portion, and a U-shaped bend pipe of an indoor heat exchanger according to a second embodiment of the present disclosure. DETAILED DESCRIPTION

[0033] <First Embodiment>

[0034] First, refer to Figure 1 , the overall structure of the air conditioner 1 according to the first embodiment of the present disclosure is described. In addition, in the following description, the directions of "up", "down", "right", "left", "front", and "rear" indicate the directions of the air conditioner 1. Figure 1 The state sets the state of the direction.

[0035] The air conditioner 1 includes an indoor heat exchanger 10, a fan and a filter (not shown), a frame 1f, and an exterior panel (not shown).

[0036] The frame 1f constitutes the bottom and rear of the air conditioner 1. The frame 1f is long in one direction and Figure 1 The fan, the exterior panel, and the indoor heat exchanger 10 are mounted on the frame 1f. The filter is mounted on the exterior panel.

[0037] The indoor heat exchanger 10 is similar to the frame 1f in one direction ( Figure 1 The left-right direction is longer.

[0038] Next, refer to Figures 1 to 9 , the structure of the indoor heat exchanger 10 is described in detail.

[0039] like Figure 1 As shown in FIG. 1 , the indoor heat exchanger 10 includes a heat exchange portion 10u, a plate stack 30, a plurality of U-shaped bends 22, and a plurality of connecting pipes 23. Figure 1 In FIG. 1 , a portion where one of the plurality of U-bend pipes 22 overlaps with the plate stack 30 in a side view is depicted by a dotted line.

[0040] The heat exchange unit 10 u includes a plurality of fins 11 , a plurality of heat transfer tubes 12 , and a tube sheet 14 .

[0041] The plurality of fins 11 are each in the shape of a thin plate, and are arranged so that the plate surface is along the up-down direction and the front-back direction. The plurality of fins 11 are arranged at equal intervals in the left-right direction.

[0042] The plurality of heat transfer tubes 12 extend in the left-right direction and penetrate the plurality of fins 11 .

[0043] In addition, Figure 1 In the figure, for simplicity, only a portion of the plurality of heat transfer tubes 12 is depicted, and only a portion of the plurality of fins 11 is partially depicted.

[0044] The left end of each heat transfer tube 12 is connected to the left end of another heat transfer tube 12 via a U-shaped bent portion 21. The right end of each heat transfer tube 12 is connected to the right end of another heat transfer tube 12 via a U-shaped bent pipe 22, a connecting pipe 23, or a plate stack 30. The bent portion 21 is located on the left side relative to the plurality of fins 11. The U-shaped bent pipe 22, the connecting pipe 23, and the plate stack 30 are located on the right side relative to the plurality of fins 11.

[0045] The bend 21 is formed integrally with the heat transfer tube 12, and a pair of heat transfer tubes 12 and the bend 21 are formed into a U-shaped tube by bending one tube. On the other hand, the U-shaped bend 22 and the connecting pipe 23 are welded to the open end (the right end of the heat transfer tube 12) of the U-shaped tube formed by bending as described above.

[0046] The U-bend pipe 22 and the connecting pipe 23 correspond to the "refrigerant pipe" of the present disclosure. The plate stack 30 includes five plates 31 to 35 stacked in the left-right direction (stacking direction) (see Figure 3 ). Refrigerant flow paths are formed in the U-shaped bend pipe 22, the connecting pipe 23, and the plate stack 30. The refrigerant flow path 22m formed in the U-shaped bend pipe 22 and the refrigerant flow path 23m formed in the connecting pipe 23 (see Figure 2 ) corresponds to the "first refrigerant flow path" of the present disclosure. The refrigerant flow path 30m formed in the plate stack 30 (see Figures 4 to 9 ) corresponds to the “second refrigerant flow path” of the present disclosure.

[0047] The refrigerant flowing in the refrigerant flow paths 22m and 23m (the "first refrigerant" of the present disclosure) is one of a liquid-phase refrigerant and a gas-phase refrigerant. The refrigerant flowing in the refrigerant flow path 30m (the "second refrigerant" of the present disclosure) is a gas-liquid two-layer refrigerant. The temperature of the liquid-phase refrigerant is lower than that of the gas-liquid two-layer refrigerant, and the temperature of the gas-phase refrigerant is higher than that of the gas-liquid two-layer refrigerant. The difference between the temperature of the liquid-phase refrigerant (the "first temperature" of the present disclosure) and the temperature of the gas-liquid two-layer refrigerant (the "second temperature" of the present disclosure), and the difference between the temperature of the gas-phase refrigerant (the "first temperature" of the present disclosure) and the temperature of the gas-liquid two-layer refrigerant (the "second temperature" of the present disclosure) are both greater than a specified value.

[0048] like Figure 1 As shown, the flow divider 18 , the expansion valve 19 , and the like are arranged near the U-bend pipe 22 , the connecting pipe 23 , and the plate stack 30 .

[0049] The tube sheet 14 is arranged so that the plate surface is along the up-down direction and the front-back direction, and is located on the right side relative to the plurality of fins 11. The plurality of heat transfer tubes 12 penetrate the tube sheet 14. There is almost no gap between the tube sheet 14 and each heat transfer tube 12, and the tube sheet 14 supports the fins 11 and the plurality of heat transfer tubes 12. On the right side of the tube sheet 14, that is, on the side opposite to the plurality of fins 11 relative to the tube sheet 14, a U-shaped bend 22, a connecting pipe 23, and a plate stack 30 are arranged.

[0050] Although not shown in the figure, a tube sheet is also arranged on the left side with respect to the plurality of fins 11 .

[0051] The plurality of heat transfer tubes 12 slightly protrude to the right from the right side of the tube plate 14. That is, the end faces 12x of the plurality of heat transfer tubes 12 are located slightly to the right of the right side of the tube plate 14.

[0052] like Figure 2 As shown, the tube sheet 14 includes a first tube sheet 141, a second tube sheet 142, a third tube sheet 143, and a fourth tube sheet 144. The indoor heat exchanger 10 is a bending type in which the first to fourth tube sheets 141 to 144 are arranged at an angle to the adjacent tube sheets 141 to 144. A plurality of heat transfer tubes 12 penetrate the first to fourth tube sheets 141 to 144, respectively. A pair of heat transfer tubes 12 in each U-shaped tube (a U-shaped tube formed by bending one tube and including a pair of heat transfer tubes 12 and a bent portion 21) does not penetrate two different tube sheets in the first to fourth tube sheets 141 to 144.

[0053] The heat exchange section 10u is composed of a rear heat exchange section 10u1 including a first tube sheet 141 and a front heat exchange section 10u2 including second to fourth tube sheets 142 to 144. The rear heat exchange section 10u1 corresponds to the "first heat exchange section" of the present disclosure, and the front heat exchange section 10u2 corresponds to the "second heat exchange section" of the present disclosure.

[0054] Two heat transfer tubes 121a and 122a adjacent to each other among the plurality of heat transfer tubes 12 included in the rear heat exchange unit 10u1 are connected via the refrigerant flow path 22m of the U-shaped bend tube 22. The two heat transfer tubes 121a and 122a respectively constitute different U-shaped tubes (U-shaped tubes formed by bending one tube and a pair of heat transfer tubes 12 and a bend 21). The heat transfer tube 121a is equivalent to the "first heat transfer tube" of the present disclosure, and the heat transfer tube 122a is equivalent to the "second heat transfer tube" of the present disclosure. Here, the two heat transfer tubes 12 are "adjacent to each other" means that there is no other heat transfer tube 12 between the two.

[0055] One of the plurality of heat transfer tubes 12 (heat transfer tube 121b) included in the rear heat exchange section 10u1 is connected to one of the plurality of heat transfer tubes 12 (heat transfer tube 122b) included in the front heat exchange section 10u2 via the refrigerant flow path 23m of the connecting pipe 23. One of the plurality of heat transfer tubes 12 (heat transfer tube 121c) included in the rear heat exchange section 10u1 is connected to one of the plurality of heat transfer tubes 12 (heat transfer tube 122c) included in the front heat exchange section 10u2 via the refrigerant flow path 23m of the connecting pipe 23. One of the plurality of heat transfer tubes 12 (heat transfer tube 121d) included in the rear heat exchange section 10u1 is connected to one of the plurality of heat transfer tubes 12 (heat transfer tube 122d) included in the front heat exchange section 10u2 via the refrigerant flow path 23m of the connecting pipe 23. One of the plurality of heat transfer tubes 12 included in the rear heat exchange section 10u1 (heat transfer tube 121e) is connected to one of the plurality of heat transfer tubes 12 included in the front heat exchange section 10u2 (heat transfer tube 122e) via a refrigerant flow path 23m of a connecting pipe 23. The heat transfer tubes 121b, 121c, 121d, and 121e correspond to the "first heat transfer tube" of the present disclosure, and the heat transfer tubes 122b, 122c, 122d, and 122e correspond to the "second heat transfer tube" of the present disclosure.

[0056] The heat transfer tube 121c is further connected to the expansion valve 19. The expansion valve 19 corresponds to the "functional component" of the present disclosure, and is mounted on the connection pipe 23 that connects the heat transfer tube 121c and the heat transfer tube 122c.

[0057] On the right side relative to the multiple fins 11, among the multiple heat transfer tubes 12 of the rear heat exchange part 10u1, except for the six heat transfer tubes 121a, 122a, 121b, 121c, 121d, and 121e connected to the U-shaped bend 22 or the connecting pipe 23, the heat transfer tubes 12 are connected to the plate stack 30.

[0058] also, Figure 3 The plate stack 30 shown is attached to the rear heat exchange section 10u1. The plate stack attached to the front heat exchange section 10u2 has the same structure as the plate stack 30, and its illustration and description are omitted.

[0059] The plate stack 30 is mounted on the heat transfer tube 12 not connected to the U-bend 22 or the connecting pipe 23 among the plurality of heat transfer tubes 12 in the rear heat exchange section 10u1 via a plurality of connecting parts 40. The plurality of connecting parts 40 are cylindrical and have a refrigerant flow path inside. Each connecting part 40 extends in the left-right direction and connects the heat transfer tube 12 and the plate stack 30 in the left-right direction. Each connecting part 40 has a left end connected to the end face 12x of the heat transfer tube 12 and a right end connected to the left side face of the plate 31 in the plate stack 30.

[0060] Concave portions 30x and 30y are provided at a portion (rear portion) of the outer periphery of the plate stack 30. The concave portions 30x and 30y penetrate the plate stack 30 in the left-right direction. The concave portions 30x and 30y are gaps formed in a shape in which the plates 31 to 35 are cut away. A U-shaped bend pipe 22 (see FIG. 2 ) is arranged at a position corresponding to the concave portion 30y. Figures 4 to 8 ).

[0061] In the present embodiment, the length of the connecting portion 40 in the left-right direction is shorter than the length of the U-shaped bend 22 in the left-right direction. A first distance D1 in the left-right direction (stacking direction) from the end face 12x of the heat transfer tube 12 to the surface closest to the end face 12x of the heat transfer tube 12 in the plate stack 30 (the left side surface of the plate 31) is shorter than a second distance D2 in the left-right direction (stacking direction) from the end face 12x of the heat transfer tube 12 to the surface farthest from the end face 12x of the heat transfer tube 12 in the U-shaped bend 22 (the top of the U shape) (see FIG. 1 ). Figure 1 ). Therefore, if Figure 1 As shown, the U-bend pipe 22 overlaps the plate stack 30 when viewed from the front-rear direction.

[0062] Next, refer to Figures 4 to 9 , the refrigerant flow path 30m formed in the plate stack 30 will be described in detail.

[0063] The refrigerant flow path 30 m is formed by through holes formed in the plates 31 to 35 constituting the plate stack 30 .

[0064] like Figure 4 As shown, a plurality of circular holes (including circular holes 313a and 314a described later) are formed on the plate 31. The connecting parts 40 (see Figure 3 ) on the right side.

[0065] like Figure 5 As shown, a plurality of circular holes (including circular holes 323x, 324x, 323a described later) and a plurality of elongated holes (including elongated holes 321y, 322y, 323y, 324a described later) are formed on the plate 32. These circular holes and elongated holes are connected to one or two of the plurality of circular holes formed on the plate 31.

[0066] like Figure 6 As shown, a plurality of circular holes (including a circular hole 334 a described later) are formed in the plate 33. The circular holes are connected to one of the circular holes or the elongated holes formed in the plate 32, respectively.

[0067] like Figure 7 As shown, a plurality of elongated holes (including elongated holes 342x and 343a described later) are formed in the plate 34. The elongated holes are connected to two of the plurality of circular holes formed in the plate 33, respectively.

[0068] like Figure 8 As shown, a circular hole 35x is formed in the plate 35. The circular hole 35x communicates with one of the plurality of elongated holes formed in the plate 34.

[0069] The through holes (circular holes or elongated holes) formed in the plates 31 to 35 communicate with each other, thereby forming a refrigerant flow path 30 m.

[0070] Figure 2 The two heat transfer tubes 123a and 124a shown (two of the plurality of heat transfer tubes 12 included in the rear heat exchange section 10u1) are connected to each other via a refrigerant flow path 30m, wherein the refrigerant flow path 30m is composed of circular holes 313a and 314a formed in the plate 31, a circular hole 323a and an elongated hole 324a formed in the plate 32, circular holes 333a and 334a formed in the plate 33, and an elongated hole 343a formed in the plate 34. The heat transfer tube 123a corresponds to the "third heat transfer tube" of the present disclosure, and the heat transfer tube 124a corresponds to the "fourth heat transfer tube" of the present disclosure. The two heat transfer tubes 123a and 124a respectively constitute different U-shaped tubes (U-shaped tubes formed by bending one tube and a pair of heat transfer tubes 12 and a bent portion 21).

[0071] like Fig. 9 As shown, the elongated hole 342x (see Figure 7 ) straddles four elongated holes 321y, 322y, 323y, 324a formed in the plate 32 (see Figure 5 ). The elongated holes 321y, 322y, 323y, and 324a respectively constitute the first flow path 30m1 of the refrigerant flow path 30. The circular holes 323x and 324x formed in the plate 32, the circular holes formed in the plates 31 and 33, and the elongated hole 342x formed in the plate 34 constitute the second flow path 30m2 of the refrigerant flow path 30. One end of the elongated hole 342x is connected to the circular hole 323x, and the other end of the elongated hole 342x is connected to the circular hole 324x. When viewed from the left-right direction (stacked direction), the first flow path 30m1 intersects with the second flow path 30m2 (refer to Figure 5 ).

[0072] The plate 32 corresponds to the “first plate” of the present disclosure. The plate 34 is stacked at a position farther from the heat transfer tube 12 than the plate 32 in the left-right direction (stacking direction), and corresponds to the “second plate” of the present disclosure.

[0073] As described above, according to the present embodiment, on the right side relative to the plurality of fins 11, not all of the heat transfer tubes 12 are connected via the refrigerant flow path 30m of the plate stack 30, but a portion of the heat transfer tubes 12 (heat transfer tubes 121a and 122a, heat transfer tubes 121b and 122b, heat transfer tubes 121c and 122c, heat transfer tubes 121d and 122d, and heat transfer tubes 121e and 122e) are connected via the refrigerant flow path 22m of the U-bend 22 or the refrigerant flow path 23m of the connecting pipe 23 (see FIG. Figure 2 ), and the remaining heat transfer tubes 12 are connected via the refrigerant flow path 30m of the plate stack 30 (refer to Figure 3 to Figure 8 ). Thus, it is possible to suppress an increase in the size of the plate laminate 30.

[0074] Two adjacent heat transfer tubes 121a and 122a are connected via the refrigerant flow path 22m of the U-shaped elbow 22 (see Figures 4 to 8 In this case, the structure can be simplified. In addition, according to this structure, when it is necessary to cut off the portion overlapping with the U-shaped bend 22 in the plate stack 30 due to the length of the U-shaped bend 22, the area of ​​the cutout portion (recess 30y) can be reduced, thereby suppressing the influence on the refrigerant flow path 30m formed in the plate stack 30.

[0075] The difference between the temperature of the refrigerant (first refrigerant) flowing in the refrigerant flow path 22m of the U-shaped bend 22 and the temperature of the refrigerant (second refrigerant) flowing in the refrigerant flow path 30m of the plate stack 30 is greater than a specified value. Assuming that the first refrigerant and the second refrigerant having a temperature difference greater than the specified value flow in the refrigerant flow path 30m of the plate stack 30, heat exchange between the first refrigerant and the second refrigerant will occur in the plate stack 30, which may cause a large heat loss. In this regard, in the present structure, the first refrigerant flows in the refrigerant flow path 22m of the U-shaped bend 22, and the second refrigerant flows in the refrigerant flow path 30m of the plate stack 30. As a result, heat exchange between the first refrigerant and the second refrigerant does not occur in the plate stack 30, and a large heat loss does not occur.

[0076] The first refrigerant is one of a liquid phase refrigerant and a gas phase refrigerant, and the second refrigerant is a gas-liquid two-layer refrigerant. The temperature of the liquid phase refrigerant is lower than that of the gas-liquid two-layer refrigerant, and the temperature of the gas phase refrigerant is higher than that of the gas-liquid two-layer refrigerant. In this structure, a structure in which heat exchange between the first refrigerant and the second refrigerant is not generated in the plate stack 30 can be effectively realized.

[0077] A first distance D1 in the left-right direction (stacking direction) from the end face 12x of the heat transfer tube 12 to the surface closest to the end face 12x of the heat transfer tube 12 in the plate stack 30 (the left side surface of the plate 31) is shorter than a second distance D2 in the left-right direction (stacking direction) from the end face 12x of the heat transfer tube 12 to the surface farthest from the end face 12x of the heat transfer tube 12 in the U-bend 22 (the top of the U shape) (see FIG. 2 ). Figure 1 In this case, the plate stack 30 and the U-bend pipe 22 are arranged so as to overlap each other in a side view, thereby making effective use of the space.

[0078] The U-shaped bend pipe 22 is arranged at a position corresponding to the recessed portion 30y provided on the outer periphery of the plate laminate 30 (see Figures 4 to 8 ). In this case, the plate laminate 30 can be made smaller and lighter.

[0079] The heat transfer tube 121c (heat transfer tube connected to the connecting pipe 23) is connected to the expansion valve 19 via the refrigerant flow path 23m of the connecting pipe 23 (see Figure 2 In this case, the connection portion between the expansion valve 19 and the heat transfer tube 12 can use an existing structure.

[0080] One of the plurality of heat transfer tubes 12 (heat transfer tube 121b) included in the rear heat exchange section 10u1 is connected to one of the plurality of heat transfer tubes 12 (heat transfer tube 122b) included in the front heat exchange section 10u2 via the refrigerant flow path 23m of the connecting pipe 23. One of the plurality of heat transfer tubes 12 (heat transfer tube 121c) included in the rear heat exchange section 10u1 is connected to one of the plurality of heat transfer tubes 12 (heat transfer tube 122c) included in the front heat exchange section 10u2 via the refrigerant flow path 23m of the connecting pipe 23. One of the plurality of heat transfer tubes 12 (heat transfer tube 121d) included in the rear heat exchange section 10u1 is connected to one of the plurality of heat transfer tubes 12 (heat transfer tube 122d) included in the front heat exchange section 10u2 via the refrigerant flow path 23m of the connecting pipe 23. One of the plurality of heat transfer tubes 12 included in the rear heat exchange section 10u1 (heat transfer tube 121e) is connected to one of the plurality of heat transfer tubes 12 included in the front heat exchange section 10u2 (heat transfer tube 122e) via the refrigerant flow path 23m of the connecting pipe 23. If the heat transfer tubes 121b and 122b are connected via the refrigerant flow path 30m of the plate stack 30, a detour or the like needs to be provided in the refrigerant flow path 30m of the plate stack 30, and the structure may be complicated. In this regard, in the present structure, this problem can be suppressed.

[0081] The refrigerant flow path 30m of the plate stack 30 includes a first flow path 30m1 (see FIG. 1 ) formed of elongated holes 321y, 322y, 323y, and 324a formed in the plate 32. Figure 5and the second flow path 30m2 (referenced to the circular holes 323x, 324x formed in the plate 32, the circular holes formed in the plates 31, 33 and the elongated holes 342x formed in the plate 34) Figure 5 to Figure 7 ). When viewed from the left-right direction (stack direction), the first flow path (30m1) and the second flow path (30m2) intersect. In this case, instead of providing a detour in the plane of the plates 31 to 35, the first flow path 30m1 and the second flow path 30m2 intersect, thereby preventing the plate stack 30 from being enlarged in the surface direction along the plane of the plates 31 to 35.

[0082] <Second Embodiment>

[0083] Next, refer to Fig.10 An indoor heat exchanger according to a second embodiment of the present disclosure will be described.

[0084] The indoor heat exchanger of the second embodiment has the same structure as the indoor heat exchanger 10 of the first embodiment, except that the length of the connection portion 240 in the left-right direction (stacking direction) is longer than the length of the connection portion 40 in the left-right direction (stacking direction) of the first embodiment.

[0085] In the present embodiment, the length of the connection portion 240 in the left-right direction is longer than the length of the U-shaped bend pipe 22. Therefore, the U-shaped bend pipe 22 does not overlap with the plate laminate 30 when viewed from the front-rear direction.

[0086] Since the refrigerant flow path 30m of the plate stack 30 is composed of through holes or grooves of the plates 31 to 35, it is easy to form a corner, and the pressure loss at the corner may be large. In order to suppress the increase in pressure loss, it is preferred to connect the heat transfer tube 12 to the refrigerant flow path 22m of the U-shaped bend 22 where it is difficult to form a corner. In this regard, in the present structure, since the length of the connection portion 240 in the left-right direction is longer than the length of the U-shaped bend 22 in the left-right direction, the U-shaped bend 22 can be arranged between the heat transfer tube 12 and the plate stack 30 without cutting off the portion overlapping with the U-shaped bend 22 in the plate stack 30. Therefore, it is easy to adopt a structure that connects the heat transfer tube 12 to the refrigerant flow path of the U-shaped bend 22. Therefore, by adopting this structure, it is possible to suppress the increase in pressure loss.

[0087] <Modification>

[0088] In the above-mentioned embodiment, the refrigerant flow path 30m of the plate stack 30 is formed by the through hole formed in each plate 31 to plate 35, but it is not limited to this. For example, part or all of the refrigerant flow path 30m may be formed by a bottomed groove formed on each plate 31 to plate 35 by half etching or the like.

[0089] In the above-mentioned embodiment, the U-bend pipe 22 (refrigerant pipe) is arranged at a position corresponding to the recessed portion 30y provided on the outer periphery of the plate stack 30, but the present invention is not limited thereto. For example, a through hole or a recessed portion may be formed in the central portion of the plate stack, and the refrigerant pipe may be arranged at a position corresponding to the through hole or the recessed portion.

[0090] In the above-mentioned embodiment, the refrigerant flow path 30m (the second refrigerant flow path) of the plate stack 30 includes flow paths 30m1 and 30m2 (the first flow path and the second flow path) that intersect each other when viewed from the left and right direction (stacking direction), but the second refrigerant flow path may not include flow paths that intersect each other when viewed from the stacking direction.

[0091] In the above-mentioned embodiment, a heat transfer tube (for example, heat transfer tube 121b) of the rear heat exchange section 10u1 (first heat exchange section) and a heat transfer tube (for example, heat transfer tube 122b) of the front heat exchange section 10u2 (second heat exchange section) are connected via the refrigerant flow path 23m (first refrigerant flow path) of the connecting pipe 23, but the present invention is not limited thereto. For example, the two heat transfer tubes 121b and 122b may be connected via the refrigerant flow path 22m of the U-bend pipe 22, or via the refrigerant flow path 30m (second refrigerant flow path) of the plate stack 30.

[0092] In the above-mentioned embodiment, as the first heat exchange part and the second heat exchange part, the rear heat exchange part 10u1 and the front heat exchange part 10u2 sandwiched between the bent part in the bent indoor heat exchanger 10 are exemplified, but the invention is not limited thereto. For example, two heat exchange parts arranged in a straight line and without a bent part may be used as the first heat exchange part and the second heat exchange part.

[0093] The functional component is not limited to the expansion valve, and may be a flow divider or the like.

[0094] Although the embodiments have been described above, it should be understood that various modifications may be made to the form or detailed structure without departing from the spirit and scope of the claims.

[0095] Description of symbols

[0096] 1: Air conditioner;

[0097] 10: Indoor heat exchanger;

[0098] 10u: heat exchange part;

[0099] 10u1: rear heat exchange section (first heat exchange section);

[0100] 10u2: front heat exchange section (second heat exchange section);

[0101] 11: fin;

[0102] 12: heat transfer tube;

[0103] 121a, 121b, 121c, 121d, 121e: heat transfer tubes (first heat transfer tubes);

[0104] 122a, 122b, 122c, 122d, 122e: heat transfer tubes (second heat transfer tubes);

[0105] 123a: heat transfer tube (third heat transfer tube);

[0106] 124a: heat transfer tube (the fourth heat transfer tube);

[0107] 19: Expansion valve (functional component);

[0108] 22: U-bend pipe (refrigerant pipe);

[0109] 22m: refrigerant flow path (first refrigerant flow path);

[0110] 23: Connecting pipes (refrigerant pipes);

[0111] 23m: refrigerant flow path (first refrigerant flow path);

[0112] 30: Plate stack;

[0113] 30m: refrigerant flow path (second refrigerant flow path);

[0114] 30m1: 1st flow path;

[0115] 30m2: 2nd flow path;

[0116] 30x: concave part;

[0117] 32: Plate (1st plate);

[0118] 34: Plate (2nd plate);

[0119] 40, 240: connection part;

[0120] D1: 1st distance;

[0121] D2: 2nd distance.

Claims

1. An indoor heat exchanger, wherein: The indoor heat exchanger comprises: A heat exchange part, comprising fins and a plurality of heat transfer tubes passing through the fins; a refrigerant pipe forming a first refrigerant flow path; and a plate stack including a plurality of plates stacked in a stacking direction and forming a second refrigerant flow path, The plurality of heat transfer tubes include a first heat transfer tube, a second heat transfer tube, a third heat transfer tube, and a fourth heat transfer tube. The first heat transfer tube and the second heat transfer tube are connected via the first refrigerant flow path. The third heat transfer tube and the fourth heat transfer tube are connected via the second refrigerant flow path.

2. The indoor heat exchanger according to claim 1, wherein: The refrigerant pipe is a U-shaped elbow, The first heat transfer tube and the second heat transfer tube are adjacent to each other.

3. The indoor heat exchanger according to claim 1, wherein: The refrigerant pipe is a U-shaped elbow, the temperature of the first refrigerant flowing in the first refrigerant flow path is a first temperature, The temperature of the second refrigerant flowing in the second refrigerant flow path is a second temperature having a difference from the first temperature greater than a predetermined value.

4. The indoor heat exchanger according to claim 3, wherein: The first refrigerant is one of a liquid phase refrigerant and a gas phase refrigerant. The second refrigerant is a gas-liquid two-layer refrigerant.

5. The indoor heat exchanger according to claim 1, wherein: A first distance in the stacking direction from the end faces of the plurality of heat transfer tubes to a surface of the plate stack closest to the end faces is shorter than a second distance in the stacking direction from the end faces to a surface of the refrigerant tube farthest from the end faces.

6. The indoor heat exchanger according to claim 5, wherein: The refrigerant pipe is arranged at a position corresponding to a recessed portion provided on the outer periphery of the plate stack.

7. The indoor heat exchanger according to claim 1, wherein: The first heat transfer tube is connected to a functional component via the first refrigerant flow path.

8. The indoor heat exchanger according to claim 7, wherein: The functional component is an expansion valve.

9. The indoor heat exchanger according to claim 1, wherein: The heat exchange part includes a first heat exchange part and a second heat exchange part, The first heat exchange part has the first heat transfer tube. The second heat exchange portion includes the second heat transfer tube.

10. The indoor heat exchanger according to claim 1, wherein The indoor heat exchanger further includes a connection portion connecting the plate stack and at least one of the third heat transfer tube and the fourth heat transfer tube in the stacking direction. The length of the connection portion in the stacking direction is longer than the length of the refrigerant pipe in the stacking direction.

11. The indoor heat exchanger according to any one of claims 1 to 10, wherein: The plurality of plates include: a first plate; and a second plate stacked at a position farther from the plurality of heat transfer tubes than the first plate in the stacking direction. The second refrigerant flow path includes: a first flow path formed in the first plate; and A second flow path is formed in both the first plate and the second plate and intersects with the first flow path when viewed in the stacking direction.

12. An air conditioner, wherein: The air conditioner includes the indoor heat exchanger according to claim 1.

Images