EP4365511A1

EP4365511A1 - Refrigerant distributor, heat exchanger, and refrigeration cycle device

Info

Publication number: EP4365511A1
Application number: EP21948248.6A
Authority: EP
Inventors: Atsushi Takahashi; Tsuyoshi Maeda; Satoru Yanachi
Original assignee: Mitsubishi Electric Corp
Current assignee: Mitsubishi Electric Corp
Priority date: 2021-06-28
Filing date: 2021-06-28
Publication date: 2024-05-08
Also published as: JP7486671B2; JPWO2023275936A1; CN117545971A; US20240328729A1; WO2023275936A1

Abstract

A refrigerant distributor in which a refrigerant pipe and a plurality of heat transfer tubes are connected, and refrigerant flowing in from the refrigerant pipe is caused to flow through flow passages formed inside to thereby cause the refrigerant to be distributed to the plurality of the heat transfer tubes, includes a first plate-like member, a second plate-like member and a third plate-like member arranged in a first direction, the first plate-like member being a member to which the refrigerant pipe is connected and the third plate-like member being a member to which the plurality of the heat transfer tubes are connected. The first plate-like member includes an inflow passage formed so as to penetrate in the first direction and into which refrigerant flows from the refrigerant pipe, and a plurality of return flow passages that cause the refrigerant flowing from the second plate-like member side to make a return-flow to the second plate-like member side. The second plate-like member includes a plurality of through passages formed so as to penetrate in the first direction. The third plate-like member includes a plurality of projections that project in a direction opposite to the second plate-like member. Each of the plurality of the through passages is communicated with the inflow passage or one of the plurality of the return flow passages. The plurality of the projections each have, in its inside, a space that is communicated with the plurality of the through passages.

Description

Technical Field

The present disclosure relates to a refrigerant distributor that distributes refrigerant to plural heat transfer tubes, a heat exchanger including the refrigerant distributor, and a refrigeration cycle apparatus including the heat exchanger.

Background Art

In recent years, the diameter of a heat transfer tube in a heat exchanger used for an air-conditioning apparatus has been increasingly reduced to reduce a refrigerant amount and to increase the performance of the heat exchanger. When the diameter of a heat transfer tube is reduced, it is required to suppress an increase in pressure loss during the passage of refrigerant through the heat transfer tube. Thus, the number of paths that is the number of branches of the heat exchanger is increased.
To increase the number of paths, a heat exchanger usually includes a multibranch refrigerant distributor that distributes and supplies the refrigerant flowing in from one inlet flow passage, to plural paths. In this case, for the heat exchanger, a compact-size refrigerant distributor that can suppress an uneven flow of refrigerant into each of the paths is required to maintain the heat exchange performance. For example, Patent Literature 1 discloses, as such a refrigerant distributor, one configured by stacking a plate-like member having a through groove for dividing refrigerant into two branches and a plate-like member having a through hole for causing refrigerant to flow through the through groove.

Citation List

Patent Literature

Patent Literature 1: Japanese Patent No. 6782792

Summary of Invention

Technical Problem

In the refrigerant distributor of Patent Literature 1, the plate-like member having the through groove is sandwiched between other plate-like members for the through groove formed in the plate-like member to have effect as a flow passage. The refrigerant distributor of Patent Literature 1 further includes two plate-like members having only openings in which flat tubes are inserted, to ensure the insertion spaces of the flat tubes. As described above, the refrigerant distributor of Patent Literature 1 includes many plate-like members having no function of distributing refrigerant, thereby having a large size.
The present disclosure has been made to solve such an above-described problem, and an object thereof is to provide a downsized refrigerant distributor, a heat exchanger, and a refrigeration cycle apparatus including the heat exchanger.

Solution to Problem

A refrigerant distributor according to an embodiment of the present disclosure in which a refrigerant pipe and a plurality of heat transfer tubes are connected, and refrigerant flowing in from the refrigerant pipe is caused to flow through flow passages formed inside to thereby cause the refrigerant to be distributed to the plurality of the heat transfer tubes, includes a first plate-like member, a second plate-like member and a third plate-like member arranged in a first direction, the first plate-like member being a member to which the refrigerant pipe is connected and the third plate-like member being a member to which the plurality of the heat transfer tubes are connected. The first plate-like member includes an inflow passage formed so as to penetrate in the first direction and into which refrigerant flows from the refrigerant pipe, and a plurality of return flow passages that cause the refrigerant flowing from the second plate-like member side to make a return-flow to the second plate-like member side. The second plate-like member includes a plurality of through passages formed so as to penetrate in the first direction. The third plate-like member includes a plurality of projections that project in a direction opposite to the second plate-like member. Each of the plurality of the through passages is communicated with the inflow passage or one of the plurality of the return flow passages. The plurality of the projections each have, in its inside, a space that is communicated with the plurality of the through passages.

Advantageous Effects of Invention

In the present disclosure, the flow passages are partially formed in the projections of the third plate-like member to which flat tubes are connected. Thus, the refrigerant distributor according to an embodiment of the present disclosure is downsized by reducing the plate-like members that are required to form part of the flow passages.

Brief Description of Drawings

[Fig. 1] Fig. 1 is a circuit diagram of a refrigeration cycle apparatus 1 according to Embodiment 1.
[Fig. 2] Fig. 2 is a perspective view of an indoor heat exchanger 7 according to Embodiment 1.
[Fig. 3] Fig. 3 illustrates schematically a refrigerant distributor 7b according to Embodiment 1.
[Fig. 4] Fig. 4 is a perspective view of a first plate-like member 10 according to Embodiment 1.
[Fig. 5] Fig. 5 is a back view of a third plate-like member 30 according to Embodiment 1.
[Fig. 6] Fig. 6 is a perspective view of the third plate-like member 30 according to Embodiment 1.
[Fig. 7] Fig. 7 is a sectional view of the third plate-like member 30 according to Embodiment 1.
[Fig. 8] Fig. 8 is an explanatory figure of flow passages according to Embodiment 1.
[Fig. 9] Fig. 9 is an explanatory figure of the flow passages according to Embodiment 1.
[Fig. 10] Fig. 10 is a sectional view of a third plate-like member 30A according to Modification 1 of Embodiment 1.
[Fig. 11] Fig. 11 is a sectional view of a third plate-like member 30B according to Modification 2 of Embodiment 1.
[Fig. 12] Fig. 12 illustrates schematically a refrigerant distributor 7Ab according to Embodiment 2.
[Fig. 13] Fig. 13 is a perspective view of a third plate-like member 30 according to Embodiment 2.
[Fig. 14] Fig. 14 is a sectional view of the third plate-like member 30 according to Embodiment 2.
[Fig. 15] Fig. 15 is an explanatory figure of flow passages according to Embodiment 2.
[Fig. 16] Fig. 16 illustrates schematically a refrigerant distributor 7Bb according to Embodiment 3.
[Fig. 17] Fig. 17 is a perspective view of a third plate-like member 30 according to Embodiment 3.
[Fig. 18] Fig. 18 is a sectional view of the third plate-like member 30 according to Embodiment 3.
[Fig. 19] Fig. 19 is an explanatory figure of flow passages according to Embodiment 3.
[Fig. 20] Fig. 20 illustrates schematically a refrigerant distributor 7Cb according to Embodiment 4.
[Fig. 21] Fig. 21 is a perspective view of a third plate-like member 30 according to Embodiment 4.
[Fig. 22] Fig. 22 is a sectional view of the third plate-like member 30 according to Embodiment 4.
[Fig. 23] Fig. 23 is an explanatory figure of flow passages according to Embodiment 4.
[Fig. 24] Fig. 24 is an explanatory figure of the flow passages according to Embodiment 4.

Description of Embodiments

Embodiment

1

Hereinafter, a refrigeration cycle apparatus 1 including a refrigerant distributor according to Embodiment 1 will be described with reference to, for example, the drawings. In the following description, parts denoted by the same reference signs are the same or equivalent to one another, and the same applies throughout the entire descriptions of the embodiments below. Moreover, in the drawings, the relationships of the sizes of constituting members sometimes differ from the relationships of the sizes of actual ones. In addition, detailed structures are appropriately simplified or omitted. The forms of the constituting elements represented in the entire description are merely examples, and the constituting elements are not limited to the forms described in the description.
Fig. 1 is a circuit diagram of the refrigeration cycle apparatus 1 according to Embodiment 1. As Fig. 1 illustrates, the refrigeration cycle apparatus 1 includes an outdoor unit 2, an indoor unit 3, and a refrigerant pipe 4. The outdoor unit 2 includes a compressor 5, a flow-switching valve 6, an expansion valve 8, an outdoor heat exchanger 9, and an outdoor fan 9a. The indoor unit 3 includes an indoor heat exchanger 7 and an indoor fan 7a. The refrigerant pipe 4 is a pipe that connects the compressor 5, the flow-switching valve 6, the indoor heat exchanger 7, the expansion valve 8, and the outdoor heat exchanger 9 to one another and inside which refrigerant flows. The refrigerant pipe 4 and each of the devices connected to the refrigerant pipe 4 constitute a refrigerant circuit.
The compressor 5 sucks refrigerant in a low-temperature and low-pressure state, compresses the sucked refrigerant to bring the refrigerant into a high-temperature and high-pressure state, and discharges the refrigerant. The flow-switching valve 6 switches flowing directions of the refrigerant in the refrigerant circuit and is, for example, a four-way valve. The expansion valve 8 reduces the pressure of the refrigerant to expand the refrigerant and is, for example, an electronic expansion valve. The outdoor heat exchanger 9 exchanges heat between the refrigerant and outdoor air and is, for example, a fin-and-tube heat exchanger. The outdoor heat exchanger 9 operates as a condenser during a cooling operation and operates as an evaporator during a heating operation. The outdoor fan 9a is a device that sends the outdoor air to the outdoor heat exchanger 9.
The indoor heat exchanger 7 exchanges heat between indoor air and the refrigerant. The indoor heat exchanger 7 operates as an evaporator during the cooling operation and operates as a condenser during the heating operation. The indoor fan 7a is a device that sends the indoor air to the indoor heat exchanger 7 and is, for example, a cross-flow fan.
The indoor heat exchanger 7 includes a refrigerant distributor 7b. The refrigerant distributor 7b is provided on the inflow side through which the refrigerant in a liquid phase rich state flows when the indoor heat exchanger 7 operates as an evaporator. The outdoor heat exchanger 9 includes a refrigerant distributor 9b. The refrigerant distributor 9b is provided on the inflow side when the outdoor heat exchanger 9 operates as an evaporator. The refrigerant distributor 7b and the refrigerant distributor 9b will be described later.

(Cooling Operation)

Here, an operation of the refrigeration cycle apparatus 1 will be described. First, the cooling operation will be described. The refrigeration cycle apparatus 1 performs the cooling operation by switching the flow-switching valve 6 such that the discharge side of the compressor 5 and the outdoor heat exchanger 9 are connected. In the cooling operation, the refrigerant sucked into the compressor 5 is compressed by the compressor 5, and the refrigerant that has turned into a high-temperature and high-pressure gas state is discharged from the compressor 5. The refrigerant in a high-temperature and high-pressure gas state that has been discharged from the compressor 5 passes through the flow-switching valve 6 and flows into the outdoor heat exchanger 9 operating as a condenser. The refrigerant that has flowed into the outdoor heat exchanger 9 exchanges heat with the outdoor air sent by the outdoor fan 9a and is thus condensed to be liquefied. The refrigerant in a liquid state flows into the expansion valve 8 and is reduced in pressure and expanded to turn into a low-temperature and low-pressure two-phase gas-liquid state. The refrigerant in a two-phase gas-liquid state flows into the indoor heat exchanger 7 operating as an evaporator. The refrigerant that has flowed into the indoor heat exchanger 7 exchanges heat with the indoor air sent by the indoor fan 7a and is thus evaporated to be gasified. At this time, the indoor air is cooled, and air cooling is thus performed in the room. Subsequently, the evaporated refrigerant in a low-temperature and low-pressure gas state passes through the flow-switching valve 6 and is sucked into the compressor 5.

(Heating Operation)

Next, the heating operation will be described. The refrigeration cycle apparatus 1 performs the heating operation by switching the flow-switching valve 6 such that the discharge side of the compressor 5 and the indoor heat exchanger 7 are connected to one another. In the heating operation, the refrigerant sucked into the compressor 5 is compressed by the compressor 5, and the refrigerant that has turned into a high-temperature and high-pressure gas state is discharged from the compressor 5. The refrigerant in a high-temperature and high-pressure gas state that has been discharged from the compressor 5 passes through the flow-switching valve 6 and flows into the indoor heat exchanger 7 operating as a condenser. The refrigerant that has flowed into the indoor heat exchanger 7 exchanges heat with the indoor air sent by the indoor fan 7a and is thus condensed to be liquefied. At this time, the indoor air is heated, and air heating is thus performed in the room. The refrigerant in a liquid state flows into the expansion valve 8 and is reduced in pressure and expanded to turn into a low-temperature and low-pressure two-phase gas-liquid state. The refrigerant in a two-phase gas-liquid state flows into the outdoor heat exchanger 9 operating as an evaporator. The refrigerant that has flowed into the outdoor heat exchanger 9 exchanges heat with the outdoor air sent by the outdoor fan 9a and is thus evaporated to be gasified. Subsequently, the evaporated refrigerant in a low-temperature and low-pressure gas state passes through the flow-switching valve 6 and is sucked into the compressor 5.

(Indoor Heat Exchanger 7)

Hereinafter, the configuration of the heat exchanger will be described while the indoor heat exchanger 7 is referred to as an example. The outdoor heat exchanger 9 and the refrigerant distributor 9b of the outdoor heat exchanger 9 have configurations similar to the configurations of the indoor heat exchanger 7 and the refrigerant distributor 9b of the indoor heat exchanger 7, and the descriptions thereof are thus omitted. Note that, the contents of the present disclosure may be applied to only any one of the indoor heat exchanger 7 with the refrigerant distributor 9b and the outdoor heat exchanger 9 with the refrigerant distributor 9b. Fig. 2 is a perspective view of the indoor heat exchanger 7 according to Embodiment 1. In Fig. 2, the refrigerant distributor 7b side of the indoor heat exchanger 7 is enlarged. The indoor heat exchanger 7 includes the refrigerant distributor 7b, plural heat transfer tubes 50, and a gas header (not illustrated). As Fig. 2 illustrates, the refrigerant pipe 4 of the refrigeration cycle apparatus 1 and the plural heat transfer tubes 50 are connected to the refrigerant distributor 7b. The refrigerant distributor 7b causes the refrigerant flowing in from the refrigerant pipe 4 to flow through the flow passages formed inside the refrigerant distributor 7b to thereby cause the refrigerant to be distributed to the plural heat transfer tubes 50.
Each of the heat transfer tubes 50 is, for example, a flat tube having plural flow passages or a circular tube. The heat transfer tube 50 is made of, for example, copper or aluminum. An end portion of the heat transfer tube 50 on the refrigerant distributor 7b side is inserted in the refrigerant distributor 7b. Note that, although Fig. 2 illustrates a case of eight heat transfer tubes 50, the number of the heat transfer tubes is not limited thereto.
A flow of refrigerant in the indoor heat exchanger 7 according to Embodiment 1 will be described. The refrigerant flowing through the refrigerant pipe 4 flows into the refrigerant distributor 7b and is caused to be distributed to and to flow out into the plural heat transfer tubes 50 when, for example, the indoor heat exchanger 7 functions as an evaporator. The refrigerant in the plural heat transfer tubes 50 exchanges heat with, for example, the air supplied by the indoor fan 7a. Portions of the refrigerant flowing through the plural heat transfer tubes 50 flow into the gas header to merge with one another and flow out into the refrigerant pipe 4. Note that the refrigerant flows in the reverse direction when the indoor heat exchanger 7 functions as a condenser.

(Refrigerant Distributor 7b)

Fig. 3 illustrates schematically the refrigerant distributor 7b according to Embodiment 1. In Fig. 3, the refrigerant distributor 7b is developed, and the parts thereof are arranged in a line. As Fig. 3 illustrates, the refrigerant distributor 7b is formed by stacking a first plate-like member 10, a second plate-like member 20, a third plate-like member 30, and a fourth plate-like member 40 that each have, for example, a rectangular shape. The first plate-like member 10, the second plate-like member 20, the fourth plate-like member 40, and the third plate-like member 30 are arranged in this order in the X-axis direction of Fig. 3. In the following description, the X-axis direction is referred to as a stacking direction. Note that the stacking direction is equivalent to a first direction. In addition, a width direction of the refrigerant distributor 7b that is equivalent to the Y-axis direction of Fig. 3 is referred to simply as a width direction. An arrangement direction of the plural heat transfer tubes 50 that is equivalent to the Z-axis direction of Fig. 3 is referred to simply as an arrangement direction. The first plate-like member 10, the second plate-like member 20, the fourth plate-like member 40, and the third plate-like member 30 are joined into one body by, for example, brazing. The first plate-like member 10, the second plate-like member 20, the fourth plate-like member 40, and the third plate-like member 30 are processed by, for example, presswork or cutting.
Fig. 4 is a perspective view of the first plate-like member 10 according to Embodiment 1. The observing point of Fig. 4 is positioned opposite to the observing point of Fig. 3 in the stacking direction. As Figs. 3 and 4 illustrate, the first plate-like member 10 includes two lying-astride projections 12a and four lying-astride projections 12b. The lying-astride projections 12a and the lying-astride projections 12b project in a direction opposite to the second plate-like member 20. When viewed in the stacking direction, the lying-astride projections 12a are each formed so as to lie astride two heat transfer tubes 50 inserted in the refrigerant distributor 7b. When viewed in the stacking direction, the lying-astride projections 12b are each formed so as to lie astride one heat transfer tube 50 inserted in the refrigerant distributor 7b.
A return flow passage 13a is formed inside each of the lying-astride projections 12a. The return flow passage 13a causes the refrigerant flowing from a through passage 21b of the second plate-like member 20, which will be described later, to make a return-flow to a through passage 21c of the second plate-like member 20. A return flow passage 13b is formed inside each of the lying-astride projections 12b. The return flow passage 13b causes the refrigerant flowing from a through passage 21d of the second plate-like member 20, which will be described later, to make a return-flow to a through passage 21e of the second plate-like member 20. The first plate-like member 10 includes an inflow passage 11. The inflow passage 11 is formed so as to penetrate the first plate-like member 10 in the stacking direction. The refrigerant pipe 4 is connected to the first plate-like member 10, and the inside space of the refrigerant pipe 4 is communicated with the inflow passage 11. The inflow passage 11, the return flow passages 13a, and the return flow passages 13b constitute the flow passages of the refrigerant distributor 7b.
The second plate-like member 20 includes a through passage 21a, two through passages 21b, two through passages 21c, four through passages 21d, and four through passages 21e formed so as to penetrate in the stacking direction. When viewed in the stacking direction, the through passage 21a is substantially circular and is formed at substantially the center of the second plate-like member 20. The through passage 21a is communicated with the inflow passage 11 of the first plate-like member 10 and a first communication passage 41a of the fourth plate-like member 40, which will be described later. When viewed in the stacking direction, each of the through passages 21b is substantially circular and is formed adjacent to the through passage 21a in the width direction. Each of the through passages 21b is communicated with the return flow passage 13a of the first plate-like member 10 and a first communication passage 41b of the fourth plate-like member 40, which will be described later. When viewed in the stacking direction, the through passages 21c are each substantially circular, are formed at equal intervals from the through passage 21a, and are each formed at substantially the center in the width direction. Each of the through passages 21c is communicated with the return flow passage 13a of the first plate-like member 10 and a first communication passage 41c of the fourth plate-like member 40, which will be described later.
When viewed in the stacking direction, each of the through passages 21d is substantially circular and is formed adjacent to the through passage 21c in the width direction. Each of the through passages 21d is communicated with the return flow passage 13b of the first plate-like member 10 and a first communication passage 41d of the fourth plate-like member 40, which will be described later. When viewed in the stacking direction, the through passages 21e are each substantially circular and are formed alternately with the through passage 21a and the two through passages 21c in the arrangement direction. The through passages 21e are formed at equal intervals in the arrangement direction. Each of the through passages 21e is communicated with the return flow passage 13b and a second communication passage 42 of the fourth plate-like member 40, which will be described later. The through passage 21a, the two through passages 21b, the two through passages 21c, the four through passages 21d, and the four through passages 21e constitute the flow passages of the refrigerant distributor 7b.
Fig. 5 is a back view of the third plate-like member 30 according to Embodiment 1. Fig. 6 is a perspective view of the third plate-like member 30 according to Embodiment 1. The observing points of Figs. 5 and 6 are positioned opposite to the observing point of Fig. 3 in the stacking direction. As Figs. 3, 5, and 6 illustrate, the third plate-like member 30 includes 15 pieces of projections 31 that project in a direction opposite to the second plate-like member 20. Each of the projections 31 projects substantially perpendicularly from the surface of the third plate-like member 30 on the opposite side from the second plate-like member 20. Among the projections 31, eight projections 31 each have, in an end portion thereof, an insertion opening 32 in which the heat transfer tube 50 is inserted. In addition, as Fig. 3 illustrates, another projection 31 includes a branch passage 34a in its inside. Other two projections 31 each include a branch passage 34b in its inside. The other four projections 31 each include a branch passage 34c in its inside. The projections 31 having the insertion openings 32 are provided alternately with the projections 31 each including any one of the branch passage 34a, the branch passage 34b, and the branch passage 34c.
The projection 31 including the branch passage 34a is provided at substantially the center of the third plate-like member 30 in the arrangement direction. The branch passage 34a causes the first communication passage 41a and the first communication passages 41b of the fourth plate-like member 40 to be communicated. The projections 31 including the branch passages 34b are provided at equal intervals from the projection 31 including the branch passage 34a in the arrangement direction. Each of the branch passage 34b causes the first communication passage 41c and the first communication passages 41d of the fourth plate-like member 40 to be communicated. The projections 31 including the branch passages 34c are provided alternately with the projection 31 including the branch passage 34a and the two projections 31 including the branch passages 34b in the arrangement direction. The projections 31 including the branch passages 34c are formed at equal intervals in the arrangement direction. Each of the branch passages 34c causes a first communication passage 41e and the second communication passages 42 of the fourth plate-like member 40, which will be described later, to be communicated.
Fig. 7 is a sectional view of the third plate-like member 30 according to Embodiment 1. Fig. 7 illustrates enlarged three projections 31 of the third plate-like member 30 that are positioned at an end portion on the + side in the arrangement direction, in a section of the refrigerant distributor 7b cut at the center in the width direction and cut in the arrangement direction, that is, A-A section of Fig. 5. As Figs. 3 and 7 illustrate, the projections 31 having the insertion openings 32 each have an insertion space 33 in its inside. The insertion space 33 includes a space equivalent to the thickness of the third plate-like member 30. In other words, in the stacking direction, the insertion space 33 ranges from the face of the third plate-like member 30 on the second plate-like member 20 side to the downstream-side end face inside the projection 31. In the insertion space 33, a distal end portion of a corresponding heat transfer tube 50 is positioned. In addition, each of the branch passage 34a, the branch passage 34b, and the branch passage 34c includes a space equivalent to the thickness of the third plate-like member 30. In other words, in the stacking direction, each of the branch passage 34a, the branch passage 34b, and the branch passage 34c ranges from the face of the third plate-like member 30 on the second plate-like member 20 side to the downstream-side end face inside the projection 31. The insertion spaces 33, the branch passage 34a, the branch passages 34b, and the branch passages 34c constitute the flow passages of the refrigerant distributor 7b.
As Fig. 3 illustrates, the fourth plate-like member 40 includes the first communication passage 41a, two first communication passages 41b, two first communication passages 41c, four first communication passages 41d, four first communication passages 41e, and eight second communication passages 42 formed so as to penetrate in the stacking direction. When viewed in the stacking direction, the first communication passage 41a is substantially circular and is formed at substantially the center of the second plate-like member 20. The first communication passage 41a is communicated with the through passage 21a of the second plate-like member 20 and the branch passage 34a of the third plate-like member 30. That is, the through passage 21a of the second plate-like member 20 and the branch passage 34a of the third plate-like member 30 are communicated through the first communication passage 41a.
When viewed in the stacking direction, each of the first communication passages 41b is substantially circular and is formed adjacent to the first communication passage 41a in the width direction. Each of the first communication passages 41b is communicated with the through passage 21b of the second plate-like member 20 and the branch passage 34a of the third plate-like member 30. That is, the through passage 21b of the second plate-like member 20 and the branch passage 34a of the third plate-like member 30 are communicated through the first communication passage 41b. When viewed in the stacking direction, the first communication passages 41c are each substantially circular, are formed at equal intervals from the first communication passage 41a, and are each formed at substantially the center in the width direction. Each of the first communication passages 41c is communicated with the through passage 21c of the second plate-like member 20 and the branch passage 34b of the third plate-like member 30. That is, the through passage 21c of the second plate-like member 20 and the branch passage 34b of the third plate-like member 30 are communicated through the first communication passage 41c.
When viewed in the stacking direction, each of the first communication passages 41d is substantially circular and is formed adjacent to the first communication passage 41c in the width direction. Each of the first communication passages 41d is communicated with the through passage 21d of the second plate-like member 20 and the branch passage 34b of the third plate-like member 30. That is, the through passage 21d of the second plate-like member 20 and the branch passage 34b of the third plate-like member 30 are communicated through the first communication passage 41d. When viewed in the stacking direction, the first communication passages 41e are each substantially circular and are formed alternately with the first communication passage 41a and the two first communication passages 41c. The first communication passages 41e are formed at equal intervals in the arrangement direction. Each of the first communication passages 41e is communicated with the through passage 21e of the second plate-like member 20 and the branch passage 34c of the third plate-like member 30. That is, the through passage 21e of the second plate-like member 20 and the branch passage 34c of the third plate-like member 30 are communicated through the first communication passage 41e.
When viewed in the stacking direction, each of the second communication passages 42 is substantially L-shaped and is formed so as to surround the first communication passage 41e. Each of the second communication passages 42 is communicated with the branch passage 34c and the insertion space 33 of the third plate-like member 30. That is, the branch passage 34c of the third plate-like member 30 and the insertion space 33 of the third plate-like member 30 are communicated through the second communication passage 42. Thus, the through passage 21e of the second plate-like member 20 and the insertion space 33 of the third plate-like member 30 are communicated through the first communication passage 41e, the branch passage 34c of the third plate-like member 30, and the second communication passage 42. The first communication passage 41a, the two first communication passages 41b, the two first communication passages 41c, the four first communication passages 41d, the four first communication passages 41e, and the eight second communication passages 42 constitute the flow passages of the refrigerant distributor 7b.

(Flow of Refrigerant in Refrigerant Distributor 7b)

Fig. 8 is an explanatory figure of the flow passages according to Embodiment 1. Fig. 9 is an explanatory figure of the flow passages according to Embodiment 1. The flow passages illustrated in Fig. 9 are continued from the flow passages illustrated in Fig. 8. The flow passages according to Embodiment 1 will be described with reference to Figs. 8 and 9. Note that all of the branches of the flow passages are not described here, and, of the plural branches of the flow passages, one branch through which the refrigerant flowing in from the refrigerant pipe 4 flows out into one of the heat transfer tubes 50 will be described as a representative branch. First, as Fig. 8 illustrates, the refrigerant flowing in from the refrigerant pipe 4 flows, in a straight line, through the inflow passage 11 of the first plate-like member 10, through the through passage 21a of the second plate-like member 20, and through the first communication passage 41a of the fourth plate-like member 40 and reaches the branch passage 34a of the third plate-like member 30. The refrigerant that has reached the branch passage 34a of the third plate-like member 30 is divided into flows and makes a return-flow to the fourth plate-like member 40 side. The refrigerant of one divided flow passes through the first communication passage 41b of the fourth plate-like member 40 and the through passage 21b of the second plate-like member 20, reaches the return flow passage 13a of the first plate-like member 10, and makes a return-flow to the second plate-like member 20 side.
Next, as Fig. 9 illustrates, the refrigerant that has made such a return-flow passes through the through passage 21c of the second plate-like member 20 and the first communication passage 41c of the fourth plate-like member 40 and reaches the branch passage 34b of the third plate-like member 30. The refrigerant that has reached the branch passage 34b of the third plate-like member 30 is divided into flows and makes a return-flow to the fourth plate-like member 40 side. The refrigerant of one divided flow passes through the first communication passage 41d of the fourth plate-like member 40 and the through passage 21d of the second plate-like member 20, reaches the return flow passage 13b of the first plate-like member 10, and makes a return-flow to the second plate-like member 20 side.
The refrigerant that has made such a return-flow then passes through the through passage 21e of the second plate-like member 20 and the first communication passage 41e of the fourth plate-like member 40 and reaches the branch passage 34c of the third plate-like member 30. The refrigerant that has reached the branch passage 34c of the third plate-like member 30 is divided into flows and makes a return-flow to the fourth plate-like member 40 side. The refrigerant of one divided flow passes through the second communication passage 42 of the fourth plate-like member 40 and makes a return-flow to the third plate-like member 30 side. The refrigerant that has made such a return-flow reaches the insertion space 33 of the third plate-like member 30 and flows out into one of the heat transfer tubes 50.
In Embodiment 1, the insertion spaces 33, the branch passage 34a, the branch passages 34b, and the branch passages 34c, that is, some parts of the flow passages are formed in the projections 31 of the third plate-like member 30 to which the heat transfer tubes 50 are connected. Thus, the refrigerant distributor 7b of Embodiment 1 is downsized by reducing the plate-like members that are required to form parts of the flow passages.
In addition, in most cases, to cause refrigerant to smoothly flow out into the heat transfer tube 50, the insertion space 33 is required to have predetermined dimensions with which the refrigerant does not build up. When the insertion space 33 is formed in the plate-like member, dimensions such as the thickness or the width of the entire plate-like member need to be increased to satisfy the required dimensions. Here, in Embodiment 1, the insertion space 33 is formed in the projection 31 of the third plate-like member. Thus, when the dimensions of the insertion space 33 are ensured, there is no need to increase the sizes of parts not contributing to the formation of the insertion spaces 33. Thus, the refrigerant distributor 7b of Embodiment 1 can be downsized.
Similarly, the branch passage 34a, the branch passage 34b, and the branch passage 34c are also required to have predetermined dimensions with which the refrigerant does not build up, to cause refrigerant to be smoothly divided thereinto. In Embodiment 1, the branch passage 34a, the branch passage 34b, and the branch passage 34c are formed in the projections 31 of the third plate-like member. Thus, when the dimensions of the branch passage 34a, the branch passage 34b, and the branch passage 34c are ensured, there is no need to increase the sizes of parts not contributing to the formation of the insertion spaces 33. Thus, the refrigerant distributor 7b of Embodiment 1 can be downsized.
In addition, with such downsized refrigerant distributor 7b, in the indoor heat exchanger 7, the mounting areas of the heat transfer tubes 50 are ensured, and the heat exchange performance can be improved. In addition, the refrigerant distributor 7b and the indoor heat exchanger 7 can thus be reduced in weight.
In addition, in the refrigerant distributor 7b, reduction in the plate-like members that are required to form parts of the flow passages enables a simplified manufacturing process, thereby enabling manufacturing cost reduction.
In addition, in Embodiment 1, the return flow passages 13a and the return flow passages 13b, that is, some parts of the flow passages are formed in the lying-astride projections 12a and the lying-astride projections 12b of the first plate-like member 10. Thus, the refrigerant distributor 7b of Embodiment 1 is downsized by reducing the plate-like members that are required to form parts of the flow passages.
In addition, the first plate-like member 10 including the return flow passage 13a and the return flow passage 13b can cause the refrigerant that has made a round-trip between the first plate-like member 10 and the third plate-like member 30 to flow again to the third plate-like member 30 side. Thus, refrigerant can flow through the same plate-like member multiple times, and required plate-like members are thereby reduced.

(First Modification)

Fig. 10 is a sectional view of a third plate-like member 30A according to Modification 1 of Embodiment 1. Fig. 10 illustrates, in a section of the third plate-like member 30A equivalent to A-A section of Fig. 5, enlarged three projections 31 of the third plate-like member 30A that are positioned at an end portion on the + side in the arrangement direction. As Fig. 10 illustrates, a downstream region of the inside of each of the projections 31 has an arc shape. In addition, the projection 31 is formed such that the dimension thereof in the arrangement direction decreases toward the distal end portion thereof. Note that, as with Embodiment 1, the projection 31 may project substantially perpendicularly from the surface of the third plate-like member 30A on the opposite side form the second plate-like member 20.
The arc-shaped downstream region of the inside of the projection 31 can prevent the refrigerant flowing through the flow passages of the refrigerant distributor 7b from being concentrated in one place in the downstream region of the inside of the projection 31. Thus, the pressure resistance of the third plate-like member 30A is increased. Accordingly, the thickness can be reduced, and the manufacturing cost can thereby be reduced.

(Second Modification)

Fig. 11 is a sectional view of a third plate-like member 30B according to Modification 2 of Embodiment 1. Fig. 11 illustrates, in a section of the third plate-like member 30B equivalent to A-A section of Fig. 5, enlarged three projections 31 of the third plate-like member 30B that are positioned at an end portion on the + side in the arrangement direction. As Fig. 11 illustrates, parts, facing the projections 31, of the face of the third plate-like member 30B on the second plate-like member 20 side each have a tapered shape. In addition, the projection 31 is formed such that the dimension thereof in the arrangement direction decreases toward the distal end portion thereof.
With the third plate-like member 30B having such a tapered shape, sudden widening of the flow passage just in front of a position where refrigerant flows into the heat transfer tube 50 is suppressed. Thus, pressure loss is suggested, and the heat exchange performance of the indoor heat exchanger 7 can thereby be improved.

Embodiment 2

Fig. 12 illustrates schematically a refrigerant distributor 7Ab according to Embodiment 2. Embodiment 2 differs from Embodiment 1 in that the fourth plate-like member 40 is omitted, and the insertion space 33 and the branch passage 34c of the third plate-like member 30 are formed so as to be communicated. The first plate-like member 10 and the second plate-like member 20 have the same shapes as the first plate-like member 10 and the second plate-like member 20 of Embodiment 1. Note that, in the following description, the parts common to those of Embodiment 1 are denoted by the same reference signs, and the detailed description thereof will be omitted.
The flow passages of the refrigerant distributor 7Ab will be described while differences from Embodiment 1 are focused. The through passage 21a is communicated with the inflow passage 11 of the first plate-like member 10 and the branch passage 34a of the third plate-like member 30. Each of the through passages 21b is communicated with the return flow passage 13a of the first plate-like member 10 and the branch passage 34a of the third plate-like member 30. Each of the through passages 21c is communicated with the return flow passage 13a of the first plate-like member 10 and the branch passage 34b of the third plate-like member 30. Each of the through passages 21d is communicated with the return flow passage 13b of the first plate-like member 10 and the branch passage 34b of the third plate-like member 30. Each of the through passages 21e is communicated with the return flow passage 13b of the first plate-like member 10 and the branch passage 34c of the third plate-like member 30.
Fig. 13 is a perspective view of a third plate-like member 30 according to Embodiment 2. The observing point of Fig. 13 is positioned opposite to the observing point of Fig. 12 in the stacking direction. As Figs. 12 and 13 illustrate, in the third plate-like member 30, two projections 31 having the insertion spaces 33 and the projection 31 including the branch passage 34c are formed as one body. In addition, the two insertion spaces 33 and the branch passage 34c are communicated.
Fig. 14 is a sectional view of the third plate-like member 30 according to Embodiment 2. Fig. 14 illustrates enlarged three projections 31 of the third plate-like member 30 that are positioned at an end portion on the + side in the arrangement direction, in a section of the refrigerant distributor 7Ab cut at the center in the width direction and cut in the arrangement direction, that is, a section of the refrigerant distributor 7Ab equivalent to A-A section of Fig. 5. As Fig. 14 illustrates, as with Embodiment 1, the insertion space 33 and the branch passage 34c each range, in the stacking direction, from the face of the third plate-like member 30 on the second plate-like member 20 side to the downstream-side end face inside the projection 31. In addition, in Embodiment 2, the insertion spaces 33, the branch passage 34a, the branch passages 34b, and the branch passages 34c also constitute the flow passages of the refrigerant distributor 7Ab.

(Flow of Refrigerant in Refrigerant Distributor 7Ab)

Fig. 15 is an explanatory figure of the flow passages according to Embodiment 2. The flow passages according to Embodiment 2 will be described with reference to Fig. 15. Note that all of the branches of the flow passages are not described here, and, of the plural branches of the flow passage, one branch through which the refrigerant flowing in from the refrigerant pipe 4 flows out into one of the heat transfer tubes 50 will be described as a representative branch. First, as Fig. 15 illustrates, the refrigerant flowing in from the refrigerant pipe 4 passes through the inflow passage 11 of the first plate-like member 10 and the through passage 21a of the second plate-like member 20 and reaches the branch passage 34a of the third plate-like member 30. The refrigerant that has reached the branch passage 34a of the third plate-like member 30 is divided into flows and makes a return-flow to the second plate-like member 20 side. The refrigerant of one divided flow passes through the through passage 21b of the second plate-like member 20, reaches the return flow passage 13a of the first plate-like member 10, and makes a return-flow to the second plate-like member 20 side.
Next, the refrigerant that has made such a return-flow passes through the through passage 21c of the second plate-like member 20 and reaches the branch passage 34b of the third plate-like member 30. The refrigerant that has reached the branch passage 34b of the third plate-like member 30 is divided into flows and makes a return-flow to the second plate-like member 20 side. The refrigerant of one divided flow passes through the through passage 21d of the second plate-like member 20, reaches the return flow passage 13b of the first plate-like member 10, and makes a return-flow to the second plate-like member 20 side.
The refrigerant that has made such a return-flow then passes through the through passage 21e of the second plate-like member 20 and reaches the branch passage 34c of the third plate-like member 30. The refrigerant that has reached the branch passage 34c of the third plate-like member 30 is divided into the insertion spaces 33 of the third plate-like member 30. The refrigerant of one divided flow flows out into one of the heat transfer tubes 50.
In Embodiment 2, the insertion spaces 33, the branch passage 34a, the branch passages 34b, and the branch passages 34c, that is, some parts of the flow passages are formed in the projections 31 of the third plate-like member 30 to which the heat transfer tubes 50 are connected. Thus, the refrigerant distributor 7Ab of Embodiment 2 is downsized by reducing the plate-like members that are required to form parts of the flow passages.
In addition, in Embodiment 2, in the third plate-like member 30, two projections 31 having the insertion spaces 33 and the projection 31 including the branch passage 34c are formed as one body. Thus, functions of dividing the flow of refrigerant converge into the third plate-like member 30. Consequently, other plate-like members for dividing the flow of refrigerant can be omitted, and the refrigerant distributor 7Ab can thereby be further downsized.

Embodiment 3

Fig. 16 illustrates schematically a refrigerant distributor 7Bb according to Embodiment 3. As Fig. 16 illustrates, Embodiment 3 differs from Embodiment 1 in that the projections 31 including the branch passage 34a, the branch passage 34b, and the branch passage 34c are omitted, and all of the projections 31 have the insertion spaces 33 in their insides. The first plate-like member 10 and the second plate-like member 20 have the same shapes as the first plate-like member 10 and the second plate-like member 20 of Embodiment 1. Note that, in the following description, the parts common to those of Embodiment 1 are denoted by the same reference signs, and the detailed description thereof will be omitted.
A flow passage of the refrigerant distributor 7Bb will be described while differences from Embodiment 1 are focused. The through passage 21a is communicated with the inflow passage 11 of the first plate-like member 10 and a first sub-branch passage 43a of the fourth plate-like member 40, which will be described later. Each of the through passages 21b is communicated with the return flow passage 13a of the first plate-like member 10 and the first sub-branch passage 43a of the fourth plate-like member 40. Each of the through passages 21c is communicated with the return flow passage 13a of the first plate-like member 10 and a first sub-branch passage 43b of the fourth plate-like member 40, which will be described later. Each of the through passages 21d is communicated with the return flow passage 13b of the first plate-like member 10 and the first sub-branch passage 43b of the fourth plate-like member 40. Each of the through passages 21e is communicated with the return flow passage 13b of the first plate-like member 10 and a second sub-branch passage 44 of the fourth plate-like member 40, which will be described later.
Fig. 17 is a perspective view of a third plate-like member 30 according to Embodiment 3. The observing point of Fig. 17 is positioned opposite to the observing point of Fig. 16 in the stacking direction. As Figs. 16 and 17 illustrate, the third plate-like member 30 includes eight projections 31 that project in a direction opposite to the second plate-like member 20. Each of the eight projections 31 has, in end portions thereof, the insertion opening 32 in which the heat transfer tube 50 is inserted.
Fig. 18 is a sectional view of the third plate-like member 30 according to Embodiment 3. Fig. 18 illustrates enlarged two projections 31 of the third plate-like member 30 that are positioned at an end portion on the + side in the arrangement direction, in a section of the refrigerant distributor 7Bb cut at the center in the width direction and cut in the arrangement direction, that is, a section of the refrigerant distributor 7Bb equivalent to A-A section of Fig. 5. As Figs. 16 and 18 illustrate, each of the projections 31 having the insertion openings 32 has the insertion space 33 in its inside. The insertion space 33 includes a space equivalent to the thickness of the third plate-like member 30. In other words, in the stacking direction, the insertion space 33 ranges from the face of the third plate-like member 30 on the second plate-like member 20 side to the downstream-side end face inside the projection 31. In the insertion space 33, a distal end portion of a corresponding heat transfer tube 50 is positioned. In addition, a downstream region of the inside of each of the projections 31 has an arc shape. The projection 31 is formed such that the dimension thereof in the arrangement direction decreases toward an end portion thereof. In addition, in Embodiment 3, the insertion spaces 33 also constitute the flow passages of the refrigerant distributor 7Bb.
As Fig. 16 illustrates, the fourth plate-like member 40 includes the first sub-branch passage 43a, two second sub-branch passages 44, and four second sub-branch passages 44 formed so as to penetrate in the stacking direction. When viewed in the stacking direction, the first sub-branch passage 43a has a linear shape and is formed at substantially the center of the second plate-like member 20. The first sub-branch passage 43a is communicated with the through passage 21a of the second plate-like member 20 and the two through passages 21b of the second plate-like member 20. When viewed in the stacking direction, the first sub-branch passages 43b each have a linear shape and are formed at equal intervals from the first sub-branch passage 43a. Each of the first sub-branch passages 43b is communicated with the through passage 21c of the second plate-like member 20 and two through passages 21d of the second plate-like member 20.
When viewed in the stacking direction from the - side to the + side, the second sub-branch passages 44 are each substantially S-shaped and are formed alternately with the first sub-branch passage 43a and the two first sub-branch passages 43b. The second sub-branch passages 44 are formed at equal intervals in the arrangement direction. Each of the second sub-branch passages 44 is communicated with the through passage 21e of the second plate-like member 20 and two insertion spaces 33 of the third plate-like member 30. The first sub-branch passage 43a, the two second sub-branch passages 44, and the four second sub-branch passages 44 constitute the flow passages of the refrigerant distributor 7Bb.

(Flow of Refrigerant in Refrigerant Distributor 7Bb)

Fig. 19 is an explanatory figure of the flow passages according to Embodiment 3. Note that all of the branches of the flow passages are not described here, and, of the plural branches of the flow passages, one branch through which the refrigerant flowing in from the refrigerant pipe 4 flows out into one of the heat transfer tubes 50 will be described as a representative branch. First, as Fig. 19 illustrates, the refrigerant flowing in from the refrigerant pipe 4 passes through the inflow passage 11 of the first plate-like member 10 and the through passage 21a of the second plate-like member 20 and reaches the first sub-branch passage 43a of the fourth plate-like member 40. The refrigerant that has reached the first sub-branch passage 43a of the fourth plate-like member 40 is divided into flows and makes a return-flow to the second plate-like member 20 side. The refrigerant of one divided flow passes through the through passage 21b of the second plate-like member 20, reaches the return flow passage 13a of the first plate-like member 10, and makes a return-flow to the second plate-like member 20 side.
Next, the refrigerant that has made such a return-flow passes through the through passage 21c of the second plate-like member 20 and reaches the first sub-branch passage 43b of the fourth plate-like member 40. The refrigerant that has reached the first sub-branch passage 43b of the fourth plate-like member 40 is divided into flows and makes a return-flow to the second plate-like member 20 side. The refrigerant of one divided flow passes through the through passage 21d of the second plate-like member 20, reaches the return flow passage 13b of the first plate-like member 10, and makes a return-flow to the second plate-like member 20 side.
The refrigerant that has made such a return-flow then passes through the through passage 21e of the second plate-like member 20 and reaches the second sub-branch passage 44 of the fourth plate-like member 40. The refrigerant that has reached the second sub-branch passage 44 of the fourth plate-like member 40 is divided into two insertion spaces 33 of the third plate-like member 30. The refrigerant of one divided flow flows out into one of the heat transfer tubes 50.
In Embodiment 3, the insertion spaces 33, that is, some parts of the flow passage are formed in the projections 31 of the third plate-like member 30 to which the heat transfer tubes 50 are connected. Thus, in Embodiment 3, the refrigerant distributor 7Bb is also downsized by reducing the plate-like members that are required to form parts of the flow passages.

Embodiment 4

Fig. 20 illustrates schematically a refrigerant distributor 7Cb according to Embodiment 4. As Fig. 20 illustrates, Embodiment 4 differs from Embodiment 1 in that the projections 31 having the insertion spaces 33 are omitted, and all of the projections 31 each have, in its inside, any one of the branch passage 34a, the branch passage 34b, and the branch passage 34c. The first plate-like member 10, the second plate-like member 20, and the fourth plate-like member 40 have the same shapes as the first plate-like member 10, the second plate-like member 20, and the fourth plate-like member 40 of Embodiment 1. Note that, in the following description, the parts common to those of Embodiment 1 are denoted by the same reference signs, and the detailed description thereof will be omitted.
A flow passage of the refrigerant distributor 7Cb will be described while differences from Embodiment 1 are focused. Fig. 21 is a perspective view of a third plate-like member 30 according to Embodiment 4. The observing point of Fig. 21 is positioned opposite to the observing point of Fig. 20 in the stacking direction. As Figs. 20 and 21 illustrate, the third plate-like member 30 includes seven projections 31 that project in a direction opposite to the second plate-like member 20. One of the projections 31 includes the branch passage 34a in its inside. Other two projections 31 include the branch passages 34b in their insides. The other four projections 31 include the branch passages 34c in their insides. Eight insertion openings 32 are formed alternately with the projections 31 each including any one of the branch passage 34a, the branch passage 34b, and the branch passage 34c.
The positions where the projections 31 including the branch passage 34a, the branch passages 34b, and the branch passages 34c are formed are the same as those of Embodiment 1. In addition, the flow passages from the inflow passage 11 of the first plate-like member 10 to the second communication passage 42 of the fourth plate-like member 40 are also the same as those of Embodiment 1. In Embodiment 4, the branch passage 34a, the branch passages 34b, and the branch passages 34c also constitute the flow passages of the refrigerant distributor 7Cb.
In Embodiment 4, the insertion openings 32 are formed in a planar part of the third plate-like member 30. Thus, the second communication passage 42 of the fourth plate-like member 40 is communicated with the branch passage 34c of the third plate-like member 30 and the insertion opening 32 of the third plate-like member 30.
Fig. 22 is a sectional view of the third plate-like member 30 according to Embodiment 4. Fig. 22 illustrates enlarged three projections 31 of the third plate-like member 30 that are positioned at an end portion on the + side in the arrangement direction, in a section of the refrigerant distributor 7Cb cut at the center in the width direction and cut in the arrangement direction, that is, a section of the refrigerant distributor 7Cb equivalent to A-A section of Fig. 5. As Fig. 22 illustrates, a downstream region of the inside of the projection 31 has an arc shape. The projection 31 is formed such that the dimension thereof in the arrangement direction decreases toward an end portion thereof. In addition, although the fourth plate-like member 40 is omitted in Fig. 22, a distal end of the heat transfer tube 50 inserted in the refrigerant distributor 7Cb passes through the insertion opening 32 and is positioned in the second communication passage 42.

(Flow of Refrigerant in Refrigerant Distributor 7Cb)

Fig. 23 is an explanatory figure of the flow passages according to Embodiment 4. Fig. 24 is an explanatory figure of the flow passages according to Embodiment 1. The flow passages illustrated in Fig. 24 are continued from the passages illustrated in Fig. 23. The flow passages according to Embodiment 4 will be described with reference to Figs. 23 and 24. As described above, the flow passages from the inflow passage 11 of the first plate-like member 10 to the second communication passage 42 of the fourth plate-like member 40 are the same as those of Embodiment 1, thereby being omitted. As Fig. 24 illustrates, the refrigerant that has passed through the second communication passage 42 of the fourth plate-like member 40 flows out into one of the heat transfer tubes 50 inserted in the insertion openings 32.
In Embodiment 4, the branch passage 34a, the branch passages 34b, and the branch passages 34c, that is, some parts of the flow passages are formed in the projections 31 of the third plate-like member 30 to which the heat transfer tubes 50 are connected. Thus, in Embodiment 4, the refrigerant distributor 7Cb is also downsized by reducing the plate-like members that are required to form parts of the flow passages.
Although Embodiments 1 to 4 are described above, the present disclosure is not limited to Embodiments 1 to 4 described above, and modification or application may be made without departing from the spirit of the present disclosure. For example, the indoor heat exchanger 7 or the outdoor heat exchanger 9 may have plural fins joined to the heat transfer tubes 50. The fins are made of, for example, aluminum.
In addition, although the refrigerant distributor 7b with eight branches is described in Embodiments 1 to 4, this is not the only option, and the number of such branches may be changed to a number other than eight by changing the number of the branch passages.
In addition, in Embodiments 1 to 4, there is described a case in which, in the first plate-like member 10, the return flow passage 13a is formed inside the lying-astride projection 12a, and the return flow passage 13b is formed inside the lying-astride projection 12b. However, the return flow passage 13a and the return flow passage 13b may each serve as a flow passage by being formed as grooves penetrating the first plate-like member 10 and being closed by another plate-like member. In addition, the return flow passage 13a and the return flow passage 13b may each be a groove having a thickness smaller than the thickness of the first plate-like member 10. In such cases, the refrigerant distributor 7b can still be downsized as long as a part of the flow passages is formed in the projection 31 of the third plate-like member 30.
In addition, Embodiment 2 may also be combined with Modification 1 of Embodiment 1, and a downstream region of the inside of the projection 31 may have an arc shape. In addition, Embodiment 2 may also be combined with Modification 2 of Embodiment 1, and the face of the third plate-like member 30 on the second plate-like member 20 side may have a tapered shape.

Reference Signs List

1: refrigeration cycle apparatus, 2: outdoor unit, 3: indoor unit, 4: refrigerant pipe, 5: compressor, 6: flow-switching valve, 7: indoor heat exchanger, 7b: refrigerant distributor, 7Ab: refrigerant distributor, 7Bb: refrigerant distributor, 7Cb: refrigerant distributor, 7a: indoor fan, 8: expansion valve, 9: outdoor heat exchanger, 9a: outdoor fan, 9b: refrigerant distributor, 10: first plate-like member, 11: inflow passage, 12a: lying-astride projection, 12b: lying-astride projection, 13a: return flow passage, 13b: return flow passage, 20: second plate-like member, 21a: through passage, 21b: through passage, 21c: through passage, 21d: through passage, 21e: through passage, 30: third plate-like member, 30A: third plate-like member, 30B: third plate-like member, 31: projection, 32: insertion opening, 33: insertion space, 34a: branch passage, 34b: branch passage, 34c: branch passage, 40: fourth plate-like member, 41a: first communication passage, 41b: first communication passage, 41c: first communication passage, 41d: first communication passage, 41e: first communication passage, 42: second communication passage, 43a: first sub-branch passage, 43b: first sub-branch passage, 44: second sub-branch passage, 50: heat transfer tube

Claims

A refrigerant distributor in which a refrigerant pipe and a plurality of heat transfer tubes are connected, and refrigerant flowing in from the refrigerant pipe is caused to flow through flow passages formed inside to thereby cause the refrigerant to be distributed to the plurality of the heat transfer tubes; and
comprising a first plate-like member, a second plate-like member and a third plate-like member arranged in a first direction, the first plate-like member being a member to which the refrigerant pipe is connected and the third plate-like member being a member to which the plurality of the heat transfer tubes are connected, wherein

the first plate-like member includes an inflow passage formed so as to penetrate in the first direction and into which refrigerant flows from the refrigerant pipe, and

a plurality of return flow passages that cause the refrigerant flowing from the second plate-like member side to make a return-flow to the second plate-like member side;

the second plate-like member includes

a plurality of through passages formed so as to penetrate in the first direction;

the third plate-like member includes

a plurality of projections that project in a direction opposite to the second plate-like member;

each of the plurality of the through passages is communicated with the inflow passage or one of the plurality of the return flow passages; and

the plurality of the projections each have, in its inside, a space that is communicated with the plurality of the through passages.
The refrigerant distributor of claim 1, further comprising
a fourth plate-like member provided between the second plate-like member and the third plate-like member, wherein

at least two of the plurality of the projections each have an insertion opening in which one of the plurality of the heat transfer tubes is inserted;

the space formed in the inside of each of the at least two of the plurality of the projections each having the insertion opening is an insertion space in which a distal end portion of one of the plurality of the heat transfer tubes is positioned, and the space formed in the inside of each of the projections, apart from the at least two of the plurality of the projections each having the insertion space, is a branch passage that causes the refrigerant flowing in from one of the plurality of the through passages to be divided into flows;

the fourth plate-like member includes

a plurality of first communication passages and a plurality of second communication passages formed so as to penetrate in the first direction;

each of the plurality of the first communication passages causes one of the plurality of the through passages and one of the plurality of the branch passages to be communicated; and

each of the plurality of the second communication passages causes one of the plurality of the branch passages and the insertion space to be communicated.
The refrigerant distributor of claim 1,
wherein
at least two of the plurality of the projections each have an insertion opening in which one of the plurality of the heat transfer tubes is inserted;

the space formed in the inside of each of the at least two of the plurality of the projections each having the insertion opening is an insertion space in which a distal end portion of one of the plurality of the heat transfer tubes is positioned, and the space formed in the inside of each of the projections, apart from the at least two of the plurality of the projections each having the insertion space, is a branch passage that causes the refrigerant flowing in from one of the plurality of the through passages to be divided into flows; and

the at least two of the plurality of the projections each having the insertion space and the projection including the branch passage are formed as one body, and at least two of the insertion spaces and the branch passage are communicated.
The refrigerant distributor of claim 1, further comprising
a fourth plate-like member provided between the second plate-like member and the third plate-like member,
wherein

the plurality of the projections each have an insertion opening in which one of the plurality of the heat transfer tubes is inserted;

the space formed in the inside of each of the plurality of the projections is an insertion space in which a distal end portion of one of the plurality of the heat transfer tubes is positioned;

the fourth plate-like member includes

a plurality of first sub-branch passages and a plurality of second sub-branch passages formed so as to penetrate in the first direction;

each of the plurality of the first sub-branch passages causes one of the plurality of the through passages and other two of the plurality of the through passages to be communicated; and

each of the plurality of the second sub-branch passages causes one of the plurality of the through passages and two of the insertion spaces to be communicated.
The refrigerant distributor of claim 1, further comprising
a fourth plate-like member provided between the second plate-like member and the third plate-like member,
wherein

the space formed in the inside of each of the plurality of the projections is a branch passage that causes the refrigerant flowing in from one of the plurality of the through passages to be divided into flows;

the third plate-like member includes

a plurality of insertion openings formed so as to penetrate in the first direction;

one of the plurality of the heat transfer tubes is inserted in each of the plurality of the insertion openings;

the fourth plate-like member includes

a plurality of first communication passages and a plurality of second communication passages formed so as to penetrate in the first direction;

each of the plurality of the first communication passages causes one of the plurality of the through passages and one of the plurality of the branch passages to be communicated; and

each of the plurality of the second communication passages causes one of the plurality of the branch passages and one of the plurality of the insertion openings to be communicated.
The refrigerant distributor of any one of claims 1 to 5,
wherein
the inside of each of the plurality of the projections includes a downstream region having an arc shape.
The refrigerant distributor of any one of claims 1 to 6,
wherein,
in a face of the third plate-like member on the second plate-like member side, parts facing the plurality of the projections each have a tapered shape.
The refrigerant distributor of any one of claims 1 to 7,
wherein
the first plate-like member includes

a plurality of lying-astride projections that project in a direction opposite to the second plate-like member; and

each of the plurality of the lying-astride projections is formed

so as to lie astride at least one of the plurality of the heat transfer tubes when viewed in the first direction, and the return flow passage is formed in an inside of each of the plurality of the lying-astride projections.
A heat exchanger comprising:
the refrigerant distributor of any one of claims 1 to 8; and

a plurality of heat transfer tubes inserted in the refrigerant distributor.
A refrigeration cycle apparatus comprising
the heat exchanger of claim 9.