WO2017150221A1

WO2017150221A1 - Heat exchanger and air conditioner

Info

Publication number: WO2017150221A1
Application number: PCT/JP2017/005960
Authority: WO
Inventors: 洋平葛山; 青木　泰高; 秀哲立野井; 将之左海
Original assignee: 三菱重工サーマルシステムズ株式会社
Priority date: 2016-02-29
Filing date: 2017-02-17
Publication date: 2017-09-08
Also published as: AU2017227162B2; EP3376149B1; JP2017155994A; EP3376149A4; JP6656950B2; CN108291786A; EP3376149A1; AU2017227162A1

Abstract

A heat exchanger (10) is provided with: a plurality of first heat transfer tubes (21); a first header section (52); a plurality of second heat transfer tubes (22); a second header section (53); a first connecting tube (55); and a second connecting tube (56). The plurality of first heat transfer tubes (21) extend in the horizontal direction and are arranged with gaps therebetween in the vertical direction. One end of each of the plurality of first heat transfer tubes (21) is connected to the first header section (52) in a communicating state. The plurality of second heat transfer tubes (22) extend in the horizontal direction and are arranged with gaps therebetween in the vertical direction. One end of each of the plurality of second heat transfer tubes (22) is connected to the second header section (53) in a communicating state. The first connecting tube (55) connects a lower portion of the first header section (52) and an upper portion of the second header section (53). The second connecting tube (56) connects an upper portion of the first header section (52) and a lower portion of the second header section (53).

Description

Heat exchanger and air conditioner

The present invention relates to a heat exchanger and an air conditioner.
The present application claims priority based on Japanese Patent Application No. 2016-038405 filed in Japan on February 29, 2016, the contents of which are incorporated herein by reference.

As a heat exchanger for an air conditioner, one having a plurality of heat transfer tubes extending in the horizontal direction is known. A plurality of heat transfer tubes are arranged at intervals in the vertical direction. Each heat transfer tube is provided with fins on the outer surface. Both ends of the plurality of heat transfer tubes are respectively connected to a pair of headers extending in the vertical direction. In such a heat exchanger, in order to secure the flow path length of the refrigerant, the refrigerant introduced into the first header of the pair of headers and circulated through the heat transfer tube to the second header is transferred to the second header. It is configured to return and return to the first header through the heat transfer tube again.

In the second header, that is, the folded-back header, a plurality of regions are partitioned by a partition plate that partitions the header in the vertical direction. As a result, the refrigerant introduced into one area in the header via the heat transfer pipe is introduced into the other area in the header via the connection pipe, and then the plurality of heat transfer pipes connected to the other area are introduced. Via the first header on the entrance / exit side.
For example, Patent Document 1 discloses a heat exchanger in which the connection pipe is connected to a lower portion of each region in a header into which a folded refrigerant is introduced.

Japanese Patent No. 5071597

By the way, when the heat exchanger is used as an evaporator, the refrigerant introduced into one area in the header via the heat transfer tube is not necessarily vaporized, but a liquid phase refrigerant and a gas phase refrigerant. Are in a gas-liquid two-phase refrigerant state. When such a gas-liquid two-phase refrigerant is introduced into the lower part of the other region in the header via the connection pipe, the liquid phase refrigerant component having a high density is difficult to reach the upper heat transfer pipe. Therefore, the refrigerant flowing through the upper heat transfer tube has a smaller liquid-phase refrigerant flow rate, and as a result, there is a problem that the desired performance of the heat exchanger cannot be obtained.

This invention is made | formed in view of such a subject, Comprising: It aims at providing the heat exchanger which can suppress a performance fall, and the air conditioner using this heat exchanger. .

The present invention employs the following means in order to solve the above problems.
That is, the heat exchanger according to the first aspect of the present invention includes a first heat transfer tube that extends in the horizontal direction and in which a refrigerant circulates and is arranged at intervals in the vertical direction, and a cylinder that extends in the vertical direction. A first header portion in which one end of the plurality of first heat transfer tubes is connected in a communicating state, and a plurality of the first heat transfer tubes are arranged in a horizontal direction with a refrigerant flowing therein and spaced apart in the vertical direction. A first connection for connecting a second heat transfer tube, a second header portion to which one ends of the plurality of second heat transfer tubes are connected in communication, a lower portion of the first header portion, and an upper portion of the second header portion A pipe, and a second connection pipe connecting the upper part of the first header part and the lower part of the second header part.

According to such a heat exchanger, for example, among the gas-liquid two-phase refrigerant introduced into the first header part via the first heat transfer tube, the refrigerant having a large liquid phase content and a large density is provided below the first header part. It is introduced into the first connecting pipe connected to. Therefore, the refrigerant having a high density is supplied to the upper part of the second header part through the first connection pipe. On the other hand, among the gas-liquid two-phase refrigerant introduced into the first header part, the refrigerant having a large gas phase content and a low density is introduced into the second connection pipe connected to the upper part of the first header part. The small refrigerant is supplied to the lower part of the second header portion through the second connection pipe.
As a result, in the second header part, the refrigerant having a large liquid phase falls from the upper part, and the refrigerant having a large gas phase is blown up from the lower part. Therefore, mixing of the liquid phase component and the gas phase component is promoted, and the refrigerant density is made uniform throughout the entire vertical direction in the second header portion. Accordingly, it is possible to equalize the refrigerant distribution supplied to the plurality of heat transfer tubes connected to the second header portion.

The heat exchanger divides the space in the second header part into a second upper region communicating with the first connection pipe and a second lower region communicating with the second connection pipe, and penetrates vertically. You may further provide the 2nd header partition plate in which the communicating hole was formed.

Thereby, the liquid phase-rich refrigerant introduced from the upper part of the second header part temporarily stays in the second upper area. On the other hand, the refrigerant having a large gas phase introduced from below the second header part blows up to the second upper region through the communication hole. Thereby, the gas phase component does not become excessive in the upper part in the second header portion, that is, the mixing of the gas phase component and the liquid phase component can be promoted.

The heat exchanger includes a first header partition that divides a space in the first header portion into a first lower region communicating with the first connection pipe and a first upper region communicating with the second connection pipe. A plate may be further provided.

The refrigerant introduced into the first header portion via the first heat transfer tube may have a different gas-liquid ratio for each first heat transfer tube. In particular, the amount of refrigerant introduced into the first header portion from the first heat transfer tube located above is larger, and the amount of liquid phase introduced into the first header portion from the first heat transfer tube located below is larger. Therefore, the first header part is divided into the first lower region and the second upper region by the first header partition plate to supply the lower and upper parts in the second header part via the first connection tube and the second connection tube. It is possible to stabilize the gas phase and liquid phase ratio of the refrigerant to be used. Furthermore, by adjusting the vertical position of the first header partition plate, the gas-liquid ratio and the flow rate of the refrigerant supplied to the lower part and the upper part in the second header part can be adjusted to desired values.

In the above heat exchanger, at least one of the first connection pipe and the second connection pipe may have a flat tube shape in which a plurality of flow paths are arranged with a space therebetween.

Thereby, for example, compared with the case where the first connection pipe and the second connection pipe have a circular cross section, it is possible to secure a large amount of refrigerant flowing through the inside and reduce the pressure loss of the refrigerant. .

Furthermore, the heat exchanger includes a header, and the header includes a cylindrical header main body extending in a vertical direction, and a main partition plate that divides the header main body vertically, and the first header The portion may be a portion below the main partition plate in the header body, and the second header portion may be a portion above the main partition plate in the header body. .

By forming the first header part and the second header part through the main partition plate in one header, a heat exchanger having these first header part and second header part can be easily configured.
Moreover, the oil component separated from the refrigerant is guided to the first header portion without being stored in the second header portion via the second connection pipe. As a result, the oil component can be mixed in the refrigerant again, so that the shortage of oil component from the refrigerant can be suppressed.

The air conditioner according to the second aspect of the present invention includes any one of the above heat exchangers.

This makes it possible to suppress a decrease in heat exchange performance due to uneven distribution of the refrigerant and provide an efficient air conditioner.

According to the heat exchanger and the air conditioner according to one aspect of the present invention, it is possible to suppress the decrease in efficiency.

1 is an overall configuration diagram of an air conditioner according to a first embodiment of the present invention. It is a longitudinal cross-sectional view of the heat exchanger which concerns on 1st embodiment of this invention. It is a perspective view of the heat exchanger which concerns on 1st embodiment of this invention. It is a figure explaining the effect at the time of using the heat exchanger which concerns on 1st embodiment of this invention as an evaporator. It is a figure explaining the effect at the time of using the heat exchanger concerning a first embodiment of the present invention as a condenser. It is a perspective view of the heat exchanger which concerns on 2nd embodiment of this invention. It is a longitudinal cross-sectional view of the heat exchanger which concerns on 2nd embodiment of this invention. It is a perspective view of the heat exchanger which concerns on 3rd embodiment of this invention. It is a figure explaining the effect at the time of using the heat exchanger which concerns on 3rd embodiment of this invention as an evaporator. It is a figure explaining the effect at the time of using the heat exchanger which concerns on 3rd embodiment of this invention as a condenser. It is a perspective view of the 1st connecting pipe and the 2nd connecting pipe of the heat exchanger which concerns on 4th embodiment of this invention. It is sectional drawing of the heat exchanger which concerns on the 1st modification of embodiment of this invention. It is sectional drawing of the heat exchanger which concerns on the 2nd modification of embodiment of this invention. It is sectional drawing of the heat exchanger which concerns on the 3rd modification of embodiment of this invention. It is sectional drawing of the heat exchanger which concerns on the 4th modification of embodiment of this invention.

Hereinafter, an air conditioner including a heat exchanger according to a first embodiment of the present invention will be described with reference to FIGS.
As shown in FIG. 1, the air conditioner 1 includes a compressor 2, an indoor heat exchanger 3 (heat exchanger 10), an expansion valve 4, an outdoor heat exchanger 5 (heat exchanger 10), a four-way valve 6, and And a pipe 7 for connecting them. The air conditioner 1 comprises the refrigerant circuit with the above elements.

The compressor 2 compresses the refrigerant and supplies the compressed refrigerant to the refrigerant circuit.
The indoor heat exchanger 3 performs heat exchange between the refrigerant and the indoor air. The indoor heat exchanger 3 is used as an evaporator during cooling operation and absorbs heat from the room, and is used as a condenser during heating operation and dissipates heat to the room. The outdoor heat exchanger 5 performs heat exchange between the refrigerant and the outdoor air.
The expansion valve 4 reduces the pressure by expanding the high-pressure refrigerant liquefied by exchanging heat with the condenser.
The outdoor heat exchanger 5 is used as a condenser during the cooling operation and dissipates heat to the outside, and is used as an evaporator during the heating operation and absorbs heat from the outside.
The four-way valve 6 switches the direction in which the refrigerant flows between the heating operation and the cooling operation. Accordingly, during the cooling operation, the refrigerant circulates in the order of the compressor 2, the outdoor heat exchanger 5, the expansion valve 4, and the indoor heat exchanger 3. On the other hand, during the heating operation, the refrigerant circulates in the order of the compressor 2, the indoor heat exchanger 3, the expansion valve 4, and the outdoor heat exchanger 5.

Next, the heat exchanger 10 used as the indoor heat exchanger 3 and the outdoor heat exchanger 5 will be described with reference to FIGS.
The heat exchanger 10 includes a plurality of heat transfer tubes 20, a plurality of fins 23, a pair of headers 30, a first connection tube 55, and a second connection tube 56.

The heat transfer tube 20 is a tubular member extending linearly in the horizontal direction, and a flow path through which the refrigerant flows is formed. A plurality of such heat transfer tubes 20 are arranged at intervals in the vertical direction, and are arranged in parallel to each other.
In the present embodiment, each heat transfer tube 20 has a flat tubular shape, and a plurality of flow paths arranged in parallel in the horizontal direction perpendicular to the extending direction of the heat transfer tube 20 are formed inside the heat transfer tube 20. Yes. The plurality of flow paths are arranged in parallel to each other. Thereby, the external shape of the cross section orthogonal to the extending direction of the heat transfer tube 20 is a flat shape with the horizontal direction orthogonal to the extending direction of the heat transfer tube 20 as the longitudinal direction.

The fins 23 are respectively disposed between the heat transfer tubes 20 arranged as described above. The fins 23 of the present embodiment have a so-called corrugated shape that extends so as to alternately contact the adjacent heat transfer tubes 20 in the extending direction of the heat transfer tubes 20. In addition, the shape of the fin 23 is not limited to this, and may be any shape as long as it is provided so as to protrude from the outer peripheral surface of the heat transfer tube 20.

The pair of headers 30 are provided at both ends of the plurality of heat transfer tubes 20 so as to sandwich the heat transfer tubes 20 from the extending direction of the heat transfer tubes 20. One header of the pair of headers 30 is an entrance / exit header 40 that serves as an entrance / exit into the heat exchanger 10 for refrigerant from the outside. The other header is a return side header 50 for returning the refrigerant in the heat exchanger 10.

The entrance / exit-side header 40 is a cylindrical member extending in the vertical direction, and has an upper end and a lower end closed. The entrance / exit side header 40 is partitioned into two upper and lower regions by a partition plate 41. A lower area partitioned by the partition plate 41 in the entrance / exit header 40 is a lower entrance / exit area 42, and an upper area is an upper entrance / exit area 43. The lower entrance / exit area 42 and the upper entrance / exit area 43 are not in communication with each other in the entrance / exit header 40. The lower entry / exit area 42 and the upper entry / exit area 43 are connected to the pipes 7 constituting the refrigerant circuit.
Here, among the plurality of heat transfer tubes 20 connected to the inlet / outlet side header 40, the heat transfer tube 20 connected in communication with the lower input / output region 42 is a first heat transfer tube 21, and an upper input / output region 43. The heat transfer tube 20 connected in communication with the second heat transfer tube 22 is a second heat transfer tube 22.

The folded-back header 50 includes a header body 51 and a main partition plate 54.
The header main body 51 is a cylindrical member extending in the vertical direction, and the upper end and the lower end are closed. The main partition plate 54 is provided in the header body 51 and divides the space in the header body 51 into two upper and lower areas. A portion below the main partition plate 54 of the header body 51 is a first header portion 52, and a portion above the main partition plate 54 of the header body 51 is a second header portion 53. That is, in this embodiment, the header main body 51 is partitioned by the main partition plate 54, so that the first header portion 52 and the second header portion 53 each having a space are formed in the folded-back header 50. Yes. In other words, the first header portion 52 and the second header portion 53 constitute the folded-back header 50.

The first heat transfer tubes 21 are connected to the first header portion 52 so as to communicate with the inside of the first header portion 52, respectively. Moreover, the 2nd heat exchanger tube 22 is connected to the 2nd header part 53 so that it may be in a communication state with the inside of the 2nd header part 53, respectively. In other words, the heat transfer tube 20 connected to the first header portion 52 is the first heat transfer tube 21, and the heat transfer tube 20 connected to the second header portion 53 is the second heat transfer tube 22. In the present embodiment, the second heat transfer tubes 22 are provided more than the first heat transfer tubes 21, but the present invention is not limited to this, and the first heat transfer tubes 21 are more than the second heat transfer tubes 22. It may be provided. Further, the same number of first heat transfer tubes 21 and second heat transfer tubes 22 may be provided.

The first connection pipe 55 is a tubular member having a flow path formed therein, and one end of the first connection pipe 55 is connected to the first header part 52 in communication with the inside of the first header part 52. The end is connected to the second header portion 53 in communication with the inside of the second header portion 53. More specifically, one end of the first connection pipe 55 is connected to the lower portion of the first header portion 52. On the other hand, the other end of the first connection pipe 55 is connected to the upper part of the second header portion 53.

Here, one end of the first connection pipe 55 is connected to the first header part 52 of the first heat transfer pipe 21 located at the lowest position among the plurality of first heat transfer pipes 21 connected to the first header part 52. It is preferable to be connected to the first header portion 52 at a position where at least a portion overlaps in the vertical direction (a position where at least a portion overlaps when viewed from the horizontal direction).
Further, the other end of the first connection pipe 55 is connected to the second header part 53 of the second heat transfer pipe 22 located at the uppermost position among the plurality of second heat transfer pipes 22 connected to the second header part 53. It is preferable to be connected to the first header portion 52 at a position where at least a portion overlaps in the vertical direction (a position where at least a portion overlaps when viewed from the horizontal direction).

The second connection pipe 56 is a tubular member having a flow path formed therein, and, like the first connection pipe 55, one end communicates with the inside of the first header portion 52 with respect to the first header portion 52. And the other end is connected to the second header portion 53 in communication with the inside of the second header portion 53. On the other hand, unlike the first connection pipe 55, the second connection pipe 56 has one end connected to the upper part in the first header part 52 and the other end connected to the upper part in the second header part 53.

It should be noted that one end of the second connection pipe 56 only needs to be connected to the first header portion 52 above one end of the first connection pipe 55. Further, the other end of the second connection pipe 56 only needs to be connected to the second header portion 53 below the other end of the first connection pipe 55.

Further, one end of the second connection pipe 56 is connected to the first header part 52 of the first heat transfer pipe 21 located at the uppermost position among the plurality of first heat transfer pipes 21 connected to the first header part 52. On the other hand, it is preferable to be connected to the first header portion 52 at a position where at least a portion overlaps in the vertical direction (a position where at least a portion overlaps when viewed from the horizontal direction).
Further, the other end of the second connection pipe 56 is connected to the second header part 53 of the second heat transfer pipe 22 located at the lowest position among the plurality of second heat transfer pipes 22 connected to the second header part 53. It is preferable to be connected to the first header portion 52 at a position where at least a portion overlaps in the vertical direction (a position where at least a portion overlaps when viewed from the horizontal direction).

Next, operations and effects when the heat exchanger 10 is used as an evaporator will be described.
When the heat exchanger 10 is the indoor heat exchanger 3, it is used as an evaporator during the cooling operation of the air conditioner 1, and when the outdoor heat exchanger 5 is used, it evaporates during the heating operation of the air conditioner 1. It will be used as a container.

When the heat exchanger 10 is used as an evaporator, liquid-phase refrigerant is supplied from the pipe 7 to the lower inlet / outlet region 42 of the inlet / outlet header 40 shown in FIG. This refrigerant is distributed and supplied into the plurality of first heat transfer tubes 21 in the lower entrance / exit region 42, and is evaporated by exchanging heat with the external atmosphere of the first heat transfer tubes 21 in the process of flowing through the first heat transfer tubes 21. Is prompted. As a result, the refrigerant supplied from the first heat transfer tube 21 into the first header portion 52 of the folded-back header 50 is a gas-liquid mixture of a liquid phase and a gas phase due to a partial change from the liquid phase to the gas phase. It becomes a two-phase refrigerant.

As shown in FIG. 4, among the gas-liquid two-phase refrigerant supplied into the first header section 52, the refrigerant having a large liquid phase content and a large density gathers under the first header section 52 due to gravity, and A refrigerant having a large phase and a low density gathers at the top of the first header portion 52. As a result, the refrigerant having a high liquid phase content is introduced into the first connection pipe 55 connected to the lower portion of the first header section 52, and is introduced into the second header section 53 through the first connection pipe 55. On the other hand, the refrigerant having a large gas phase content is introduced into the second connection pipe 56 connected to the upper portion of the first header section 52, and is introduced into the second header section 53 through the second connection pipe 56.

Thereby, a refrigerant with a large liquid phase is supplied to the upper part in the second header part 53 to which the first connection pipe 55 is connected, and a refrigerant with a large liquid phase in the second header part 53 from the upper part toward the lower part. Will be poured down. On the other hand, a refrigerant with a large gas phase content is supplied to the lower part in the second header part 53 to which the second connection pipe 56 is connected, and a refrigerant with a larger gas phase part from the lower part to the upper part in the second header part 53. Will blow up. As a result, in the second header portion 53, the refrigerant having a large gas phase content and the refrigerant having a large liquid phase content are mixed with each other, and the gas-liquid ratio of the refrigerant is made uniform as a whole in the second header portion 53. Thereby, the refrigerant | coolant with which the gas-liquid ratio was equalized is supplied to the some 2nd heat exchanger tube 22 connected in the 2nd header part 53, respectively.

Thereafter, the refrigerant is promoted to evaporate again by exchanging heat with the external atmosphere of the second heat transfer tube 22 in the process of flowing through the second heat transfer tube 22. As a result, the liquid phase remaining in the refrigerant changes into a gas phase in the second heat transfer tube 22, and the gas phase refrigerant is supplied to the upper entrance / exit region 43 of the inlet / outlet header 40. Then, the refrigerant is introduced into the pipe 7 from the upper entrance / exit area 43 and circulates in the refrigerant circuit.

As described above, according to the heat exchanger 10 of the present embodiment, the refrigerant having a high liquid phase content and a large density in the first header portion 52 is located above the second header portion 53 via the first connection pipe 55. On the other hand, a refrigerant with a large gas phase content and a low density in the first header portion 52 is supplied from below the second header portion 53 via the second connection pipe 56. Therefore, the density of the refrigerant is reversed upside down in the first header portion 52 and the second header portion 53. Thereby, in the 2nd header part 53, since a refrigerant | coolant with a high density moves below by gravity, a refrigerant | coolant with a low density will move upwards, Therefore The mixing of the refrigerant | coolant with these density differences was accelerated | stimulated. Above, the refrigerant can be guided to the second heat transfer tube 22. Accordingly, it is possible to equalize the refrigerant distribution supplied to the plurality of heat transfer tubes 20 connected to the second header portion 53. As a result, the flow rate of the liquid refrigerant flowing through the second heat transfer tubes 22 is made uniform regardless of the upper and lower positions of the second heat transfer tubes 22, so that the performance deterioration of the heat exchanger 10 can be suppressed.

Next, operations and effects when the heat exchanger 10 is used as a condenser will be described.
When the heat exchanger 10 is the indoor heat exchanger 3, it is used as a condenser during the heating operation of the air conditioner 1, and when the outdoor heat exchanger 5 is used, it is condensed during the cooling operation of the air conditioner 1. It will be used as a container.

When the heat exchanger 10 is used as an evaporator, a gas-phase refrigerant is supplied from the pipe 7 to the upper entrance / exit region 43 of the entrance / exit header 40 shown in FIG. This refrigerant is distributed and supplied into the plurality of second heat transfer tubes 22 in the upper entrance / exit region 43, and condensed by exchanging heat with the external atmosphere of the second heat transfer tubes 22 in the process of flowing through the second heat transfer tubes 22. Is prompted. As a result, the refrigerant supplied from the second heat transfer tube 22 into the second header portion 53 of the folded-back header 50 is partly changed from the gas phase to the liquid phase, so that the gas phase is a mixture of the liquid phase and the gas phase. It becomes a two-phase refrigerant.

As shown in FIG. 5, among the gas-liquid two-phase refrigerant supplied into the second header portion 53, the refrigerant having a large liquid phase content and a high density gathers under the second header portion 53 due to gravity, A refrigerant with a large phase content and a low density gathers at the upper part of the second header portion 53. As a result, the refrigerant with a large gas phase content is introduced into the first connection pipe 55 connected to the upper part of the second header part 53 and introduced into the lower part of the first header part 52 through the first connection pipe 55. The On the other hand, the refrigerant having a large amount of liquid phase is introduced into the second connection pipe 56 connected to the lower part of the second header part 53 and introduced into the upper part of the first header part 52 through the second connection pipe 56. . As a result, in the first header portion 52, the gas-liquid ratio of the refrigerant is made uniform as a whole in the first header portion 52 as in the second header portion 53 when the heat exchanger 10 is used as an evaporator. .

Here, the flow rate of each of the plurality of first heat transfer tubes 21 to which the refrigerant is supplied from the first header portion 52 when the heat exchanger 10 is used as a condenser is the head difference (first transfer) of the first heat transfer tubes 21. The larger the height in the inlet / outlet header 40 of the heat pipe 21 is, the larger it is. Therefore, the cooling effect from the external atmosphere is small in the first heat transfer tube 21 having a large flow rate, and the cooling effect from the external atmosphere is large in the first heat transfer tube 21 having a large flow rate. Thus, when the cooling effect by each 1st heat exchanger tube 21 varies, the performance decline as the heat exchanger 10 whole will be caused.

If there is a large amount of gas phase in the upper part of the first header portion 52, the cooling effect in the first heat transfer tube 21 disposed above is small, so that the refrigerant cannot be sufficiently condensed. On the other hand, when there is much liquid phase in the lower part in the 1st header part 52, since the cooling effect of the 1st heat exchanger tube 21 arrange | positioned below is large, it will supercool a refrigerant | coolant.
In this respect, in this embodiment, since the gas-liquid ratio in the first header portion 52 is made uniform as described above, the inconvenience when the heat exchanger 10 is used as a condenser can be suppressed. .

In either case where the heat exchanger 10 is used as an evaporator or a condenser, in the present embodiment, the lower part in the folded-back header 50 is the first header part 52 and the upper part is the second header part 53. Therefore, the oil component separated from the refrigerant can be introduced into the first header portion 52 without staying in the lower portion of the second header portion 53 via the second connection pipe 56. As a result, the oil component is mixed with the refrigerant in the first header portion 52, so that it is possible to avoid the oil component from becoming extremely insufficient from the refrigerant when performing the refrigeration cycle in the refrigerant circuit.

Next, the heat exchanger 60 which concerns on 2nd embodiment of this invention is demonstrated with reference to FIG.6 and FIG.7. In the second embodiment, the same components as those in the first embodiment are denoted by the same reference numerals as those in the first embodiment, and detailed description thereof is omitted.
As shown in FIGS. 6 and 7, the heat exchanger 60 of the second embodiment is different from the first embodiment in that the folded-back header 50 further includes a second header partition plate 61.

The second header partition 61 divides the space in the second header portion 53 into two upper and lower regions. Of these two regions, the lower region is a second lower region 63 and the upper region is a second upper region 64. The second heat transfer tubes 22 communicate with the second lower region 63 and the second upper region 64, respectively. In addition, the other end of the second connection pipe 56 communicates with the second lower region 63, and the other end of the first connection pipe 55 communicates with the second upper region 64.

The second header partition plate 61 is formed with a communication hole 62 penetrating in the vertical direction. By this communication hole 62, the second lower region 63 and the second upper region 64 are in communication with each other in a part in the horizontal direction. In other words, the second header partition plate 61 is stretched inward from the inner peripheral surface of the header body 51 so as to allow a part of the second lower region 63 and the second upper region 64 to communicate with each other in the horizontal direction. It is formed to take out.
The communication hole 62 may be formed at the center in the horizontal direction of the second header partition plate 61 or may be formed away from the center.

According to the heat exchanger 60 including the second header partition plate 61 as described above, gas-liquid mixing in the second header portion 53 particularly when the heat exchanger 60 is used as an evaporator is the same as that of the first embodiment. More than the heat exchanger 10, it can carry out more effectively.
That is, in the case of the heat exchanger 10 of the first embodiment, the refrigerant having a large gas phase supplied from the upper part of the second header part 53 and having a high density quickly falls to the lower part of the second header part 53 due to gravity. Therefore, the liquid phase may also increase at the lower part of the second header portion 53.
In particular, it becomes more conspicuous when the amount of refrigerant supplied from the upper part of the second header portion 53 is large.

On the other hand, in the present embodiment, the refrigerant having a large liquid phase introduced from the upper part of the second header part 53 quickly moves to the lower part of the second header part 53 due to the presence of the second header partition plate 61. Without being temporarily retained in the second upper region 64. Furthermore, since the refrigerant having a large amount of gas phase introduced from below the second header portion 53 is blown up to the second upper region 64 through the communication hole 62, the gas phase component is stably stabilized in the second upper region 64. Can be supplied. Thereby, it is possible to suppress the liquid phase component from being excessive in the second lower region 63 in the second header portion 53 and to suppress the gas phase component from being excessive in the second upper region 64. Can do. This makes it possible to more efficiently promote the mixing of the gas phase / liquid phase components in the second header portion 53 as a whole.

In the present embodiment, an example in which one second header partition plate 61 is provided in the second header portion 53 has been described, but a plurality of second header portions 53 are spaced apart in the vertical direction in the second header portion 53. A header partition plate 61 may be provided. Thus, it is preferable that the plurality of regions partitioned vertically are respectively connected to the second heat transfer tube 22. Moreover, it is preferable that the other end of the 2nd connecting pipe 56 is connected to the lowermost area | region among several area | regions, and the other end of the 1st connecting pipe 55 is connected to the uppermost area | region.
Moreover, when providing the several 2nd header partition plate 61, it is preferable that the communicating hole 62 formed in each 2nd header partition plate 61 is formed in the position which does not mutually overlap seeing from an up-down direction. Thereby, the liquid phase can be retained more effectively in each region, and gas-liquid mixing in each region can be performed more efficiently.

Next, a heat exchanger 70 according to a third embodiment of the present invention will be described with reference to FIGS. In the third embodiment, components similar to those in the first embodiment are denoted by the same reference numerals as those in the first embodiment, and detailed description thereof is omitted.
As shown in FIGS. 8 to 10, the heat exchanger 70 of the third embodiment is different from the first embodiment in that the folded-back header 50 further includes a first header partition plate 71.

The first header partition plate 71 divides the space in the first header portion 52 into two upper and lower regions. Of these two regions, the lower region is a first lower region 72 and the upper region is a first upper region 73. The first heat transfer tubes 21 communicate with the first lower region 72 and the first upper region 73, respectively. In addition, one end of the first connection pipe 55 is communicated with the first lower region 72, and one end of the second connection pipe 56 is communicated with the first upper region 73.
The first lower region 72 and the first upper region 73 are not in communication within the first header portion 52.

The effect in the case of using the heat exchanger 70 of 3rd embodiment as an evaporator is demonstrated.
The refrigerant introduced into the first header part 52 via the first heat transfer tube 21 may have a different gas / liquid ratio for each first heat transfer tube 21. In particular, as shown in FIG. 9, the refrigerant introduced into the first header portion 52 from the first heat transfer tube 21 positioned above has a larger amount of gas phase, and the first heat transfer tube 21 positioned below the first header portion 52. The refrigerant introduced into the interior has more liquid phase. Therefore, the first header portion 52 is partitioned into the first lower region 72 and the first upper region 73 by the first header partition plate 71, so that the second header is connected via the first connection pipe 55 and the second connection pipe 56. The gas phase and the liquid phase ratio of the refrigerant supplied to the lower part and the upper part in the part 53 can be stabilized.
Further, by adjusting the vertical position of the first header partition plate 71, the gas-liquid ratio and the flow rate of the refrigerant supplied to the lower part and the upper part in the second header part 53 can be adjusted to desired values.

Next, the effect in the case of using the heat exchanger 70 of 3rd embodiment as a condenser is demonstrated.
In the present embodiment, a refrigerant with a large amount of gas phase is supplied to the first lower region 72 in the first header portion 52, and a refrigerant with a large amount of liquid phase is supplied to the first upper region 73.
Therefore, when the flow rate of the first heat transfer tube 21 located below among the plurality of first heat transfer tubes 21 is small and the cooling effect is relatively large due to the difference in the header 30 as described above, the first heat transfer tube 21 is circulated. Since the refrigerant has a large gas phase content, it can be appropriately condensed without supercooling the refrigerant. On the other hand, even when the flow rate of the first heat transfer tube 21 positioned above among the plurality of first heat transfer tubes 21 is large due to the difference in the header 30 and the cooling effect is relatively small, the refrigerant flowing through the first heat transfer tube 21 is already present. There is no inconvenience because there is much condensed liquid phase.
Therefore, the refrigerant can be more efficiently condensed as the heat exchanger 70 as a whole.

Next, the heat exchanger 80 which concerns on 4th embodiment of this invention is demonstrated with reference to FIG.
The heat exchanger 80 of the fourth embodiment differs from the first to third embodiments in that the shapes of the first connecting pipe 81 and the second connecting pipe 82 are flat tubes as shown in FIG. To do.

That is, the first connection pipe 81 and the second connection pipe 82 of the third embodiment are the same as those of the first connection pipe 81 and the second connection pipe 82 of the first to third embodiments. While being connected to the two header parts 53, it has the same structure as the heat transfer tube 20 of the first to third embodiments, that is, a plurality of flow paths arranged in one direction at intervals inside. It has a flat tubular shape. Therefore, compared with the first connecting pipe 81 and the second connecting pipe 82 of the first to third embodiments having a circular cross section, the first connecting pipe 81 and the second connecting pipe 82 of the third embodiment are circulated inside. A large amount of refrigerant can be ensured and pressure loss of the refrigerant can be reduced.

The embodiment of the present invention has been described above, but the present invention is not limited to this, and can be appropriately changed without departing from the technical idea of the present invention.

For example, in the embodiment, the example in which the first header portion 52 and the second header portion 53 are formed integrally with the header body 51 of the folded-back header 50 has been described. However, the present invention is not limited to this, and the first header part 52 and the second header part 53 may be arranged independently of each other as in the first modification shown in FIG. In this case, the first connecting pipe 55 and the second connecting pipe 56 are connected so that the first header portion 52 and the second header portion 53 are overlaid on each other. In the first modification, the first header portion 52 and the second header portion 53 are arranged at the same vertical position, but may be arranged at different vertical positions.

Further, for example, as in the second modification shown in FIG. 13, the first header portion is configured so that the refrigerant returned to the inlet / outlet header 40 is supplied again to the return header 50 and then returned to the inlet / outlet header 40. Two sets of 52 and the second header portion 53 may be provided in the return side header 50 and one set may be provided in the entrance / exit side header 40.

Furthermore, you may comprise so that the heat exchanger 10 of this embodiment may be arrange | positioned two steps up and down like the 3rd modification shown in FIG. 14, for example.
Further, for example, as in the fourth modification shown in FIG. 15, the first header portion 52 and the second header portion 53 that are adjacent to each other in the upper and lower sides are provided in the folded header 30, and the first header portion 52 and the second header portion 53 are provided. The 1st header part 52 and the 2nd header part 53 may be provided so that may be pinched | interposed from the upper and lower sides, and the inside / outlet side header 40 inside may be divided so as to correspond to this.

DESCRIPTION OF SYMBOLS 1 Air conditioner 2 Compressor 3 Indoor heat exchanger 4 Expansion valve 5 Outdoor heat exchanger 6 Four way valve 7 Piping 10 Heat exchanger 20 Heat transfer tube 21 First heat transfer tube 22 Second heat transfer tube 23 Fin 30 Header 40 Entrance / exit side header 41 Partition Plate 42 Lower Access Area 43 Upper Access Area 50 Return Side Header 51 Header Main Body 52 First Header Portion 53 Second Header Portion 54 Main Partition Plate 55 First Connection Pipe 56 Second Connection Pipe 60 Heat Exchanger 61 Second Header Partition plate 62 Communication hole 63 Second lower region 64 Second upper region 70 Heat exchanger 71 First header partition plate 72 First lower region 73 First upper region 80 Heat exchanger 81 First connection pipe 82 Second connection pipe

Claims

A first heat transfer tube that extends in the horizontal direction and has a plurality of refrigerants arranged in the vertical direction with a refrigerant flowing therethrough,
A first header portion that is formed in a cylindrical shape extending in the up-down direction and one end of the plurality of first heat transfer tubes is connected in a communicating state;
A second heat transfer tube extending in the horizontal direction and having a plurality of refrigerants arranged in the vertical direction with a refrigerant flowing through the interior;
A second header part to which one end of the plurality of second heat transfer tubes is connected in a communicating state;
A first connection pipe connecting the lower part of the first header part and the upper part of the second header part;
A heat exchanger comprising: a second connection pipe that connects an upper part of the first header part and a lower part of the second header part.
A space in the second header portion is partitioned into a second upper region communicating with the first connection pipe and a second lower region communicating with the second connection pipe, and a communication hole penetrating vertically is formed. The heat exchanger according to claim 1, further comprising a second header partition plate.
The first header partition plate for partitioning a space in the first header portion into a first lower region communicating with the first connection pipe and a first upper region communicating with the second connection pipe. The heat exchanger according to 1 or 2.
The at least one of said 1st connection pipe and said 2nd connection pipe has comprised the flat tube | pipe which has the flow path arranged in multiple numbers at intervals mutually inside. Heat exchanger.
A header,
The header has a cylindrical header body extending in the vertical direction, and a main partition plate that partitions the header body vertically.
The first header portion is in the header body and is a portion below the main partition plate,
The heat exchanger according to any one of claims 1 to 4, wherein the second header portion is a portion above the main partition plate in the header main body.
An air conditioner comprising the heat exchanger according to any one of claims 1 to 5.