US20230375239A1

US20230375239A1 - Refrigeration cycle device

Info

Publication number: US20230375239A1
Application number: US18/247,968
Authority: US
Inventors: Ryohei ARAKI
Original assignee: Mitsubishi Electric Corp
Current assignee: Mitsubishi Electric Corp
Priority date: 2021-02-01
Filing date: 2021-02-01
Publication date: 2023-11-23
Also published as: JPWO2022162931A1; WO2022162931A1; CN116670448A; DE112021006979T5

Abstract

An aspect of a refrigeration cycle device according to the present disclosure includes an outdoor unit including a heat exchanger; a temperature detection device attached to the heat exchanger; and a controller that makes the refrigeration cycle device to perform a defrosting operation, wherein the heat exchanger comprises a heat exchanger main body including a plurality of heat transmission pipes arranged side by side in a predetermined direction; a first/second collecting pipe connected to a first/second end portion of the plurality of heat transmission pipes; and a first/second port portion communicated with the heat exchanger main body via the first collecting pipe, during the defrosting operation, the controller terminates the defrosting operation in a case in which the temperature acquired by the temperature detection device is equal to or higher than a predetermined temperature.

Description

CROSS-REFERENCE TO RELATED APPLICATION

This application is a U.S. national stage application of International Application No. PCT/JP2021/003497 filed on Feb. 1, 2021, the contents of which are incorporated herein by reference.

TECHNICAL FIELD

The present disclosure relates to a refrigeration cycle device.

BACKGROUND

A refrigeration cycle device capable of executing a defrosting operation to remove frost generated in a heat exchanger of an outdoor unit is known. For example, in Patent Document 1, an air conditioner as such a refrigeration cycle device is disclosed.

PATENT DOCUMENT

Patent Document

1

Japanese Unexamined Patent Application, First Publication No. H8-75326

In the refrigeration cycle device as described above, the heat exchanger of the outdoor unit may have a plurality of heat transmission pipes arranged side by side in a predetermined direction. When a defrosting operation is performed in such a refrigeration cycle device, for example, the controller of the refrigeration cycle device, determines that the frost has been removed to terminate the defrosting operation when temperature of the refrigerant flowing out from the inside of a plurality of heat transmission pipes is equal to or larger than a certain temperature. However, there may be a case in which the temperature of the refrigerant flowing through the heat transmission pipes vary, and even if the temperature of the refrigerant flowing out of the heat transmission pipes is equal to or larger than the certain temperature, the temperature of the refrigerant flowing inside a part of the heat transmission pipe may be lower than the certain temperature. Accordingly, there is a possibility that the frost remains around the part of the heat transmission pipes. Whereas, if the defrosting operation is performed for a certain period of time even after the temperature of the refrigerant that has flowed out of the plurality of heat transmission pipes is equal to or larger than the certain temperature, it is possible to prevent the frost from remaining. However, in this case, the problem may arise that the execution time of the defrosting operation becomes longer, and the time during which the refrigeration cycle device cannot execute other operations becomes longer.

SUMMARY

In view of the above circumstances, one object of the present disclosure is to provide a refrigeration cycle device for preventing the execution time of the defrosting operation from becoming longer.
An aspect of a refrigeration cycle device according to the present disclosure is a refrigeration cycle device including an outdoor unit with a heat exchanger; a temperature detection device attached to the heat exchanger; and a controller that makes the refrigeration cycle device to perform a defrosting operation for removing frost generated in the heat exchanger based on temperature acquired by the temperature detection device, wherein the heat exchanger includes a heat exchanger main body including a plurality of heat transmission pipes arranged side by side in a predetermined direction; a first collecting pipe connected to a first end portion of the plurality of heat transmission pipes; a second collecting pipe connected to a second end portion of the plurality of heat transmission pipes, and a first port portion and a second port portion communicated with the heat exchanger main body via the first collecting pipe, the first port portion is positioned at a first side of the second port portion in the predetermined direction, the plurality of heat transmission pipes comprises a plurality of first heat transmission pipes; and a plurality of second heat transmission pipes positioned at a second side of the plurality of first heat transmission pipes in the predetermined direction, the first collecting pipe comprises a first connection portion communicating an inside of the plurality of first heat transmission pipes and an inside of the first port portion; and a second connection portion communicating an inside of the plurality of second heat transmission pipes and an inside of the second port portion, during the defrosting operation, refrigerant flowing to the inside of the heat exchanger from the first port portion flows to the inside of the plurality of first heat transmission pipes, the refrigerant flowing to the inside of the plurality of first heat transmission pipes flows to an inside of the plurality of second heat transmission pipes, and the refrigerant flowing to the inside of the plurality of second heat transmission pipes joins at the second connection portion and then flows out of the heat exchanger from the second port portion, the temperature detection device is arranged at an upstream side of the second connection portion along a flow direction of the refrigerant during the defrosting operation and attached to an end portion in the heat exchanger main body at a second side in the predetermined direction, and during the defrosting operation, the controller terminates the defrosting operation in a case in which the temperature acquired by the temperature detection device is equal to or higher than a predetermined temperature.
According to the aspect of the present disclosure, it is possible to prevent the execution time of the defrosting operation from becoming longer in the refrigeration cycle device.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a schematic view showing a schematic configuration of a refrigeration cycle device according to a first embodiment.

FIG. 2 is a perspective view showing a heat exchanger according to the first embodiment.

FIG. 3 is a cross-sectional view showing the heat exchanger according to the first embodiment as a cross-sectional view taken along the line III-III in FIG. 2 .

FIG. 4 is a cross-sectional view showing an outdoor unit of a heat exchanger according to a second embodiment.

DETAILED DESCRIPTION

Hereinafter, a refrigeration cycle device according to an embodiment of the present disclosure will be described with reference to the drawings. It is noted that the scope of the present disclosure is not limited to the following embodiments, and can be arbitrarily changed within the scope of the technical ideas of the present disclosure. In the drawings shown below, the scale and number of each structure may be different from the scale and number of the actual structure in order to make each configuration easier to understand.

First Embodiment

FIG. 1 is a schematic view showing a schematic configuration of a refrigeration cycle device 100 according to a first embodiment. The refrigerating cycle device 100 is a device that adopts a refrigerating cycle in which a refrigerant 40 circulates therein. The refrigeration cycle device 100 according to the first embodiment is an air conditioner. As shown in FIG. 1 , the refrigeration cycle device 100 includes an outdoor unit 10, an indoor unit 20, and a circulation path portion 30. The outdoor unit 10 is arranged outdoors. The indoor unit 20 is arranged indoors. The outdoor unit 10 and the indoor unit 20 are connected to each other by the circulation path portion 30 through which the refrigerant 40 circulates.
The refrigeration cycle device 100 can adjust the temperature of the indoor air by exchanging heat between the refrigerant 40 flowing through the circulation path portion 30 and the indoor air in which the indoor unit 20 is arranged. As the refrigerant 40, for example, a fluorine-based refrigerant, a hydrocarbon-based refrigerant or the like having a low global warming potential (GWP) can be used.
The outdoor unit 10 has an outdoor unit housing 11, a compressor 12, a heat exchanger 13, a flow rate adjustment valve 14, a blower fan 15, a four-way valve 16, and a controller 17. The compressor 12, the heat exchanger 13, the flow rate adjustment valve 14, the blower fan 15, the four-way valve 16, and the controller 17 are accommodated inside the outdoor unit housing 11.
The compressor 12, the heat exchanger 13, the flow rate adjustment valve 14 and the four-way valve 16 are provided in a portion of the circulation path portion 30 located inside the outdoor unit housing 11. The compressor 12, the heat exchanger 13, the flow rate adjustment valve 14, and the four-way valve 16 are connected by the portion of the circulation path portion 30 located inside outdoor unit housing 11.
The compressor 12 compresses the low-pressure refrigerant 40 that has flowed into the compressor 12 to generate the high-pressure refrigerant 40. The compressor 12 may have any structure as long as the compressor 12 can compress the refrigerant 40. The compressor 12 is, for example, a capacity-controllable inverter compressor. The refrigerant 40 circulates in the circulation path portion 30 by driving the compressor 12.
FIG. 2 is a perspective view showing the heat exchanger 13 according to the first embodiment. FIG. 3 is a cross-sectional view showing the heat exchanger 13 according to the first embodiment which is taken along line III-III in FIG. 2 . In FIG. 2 and FIG. 3 , an X-axis, a Y-axis orthogonal to the X-axis, and a Z-axis orthogonal to both the X-axis and the Y-axis are shown. A direction parallel to the X-axis is a front-rear direction of the outdoor unit 10. A direction parallel to the Y-axis is a left-right direction of the outdoor unit 10. A direction parallel to the Z-axis is a vertical direction. In the following description, the direction parallel to the X-axis is referred to as the “front-rear direction X”, the direction parallel to the Y-axis is referred to as the “left-right direction Y”, and the direction parallel to the Z-axis is referred to as the “vertical direction Z”.
The front-rear direction X, the left-right direction Y, and the vertical direction Z are directions orthogonal to each other. The side (+X side) in the front-rear direction X to which the arrowhead of the X-axis faces is referred to as the front side. The side (−X side) in the front-rear direction X that is opposite to the side to which the arrowhead of the X-axis faces is referred to as the rear side. The side (+Y side) in the horizontal direction Y to which the Y-axis arrowhead faces is referred to as the left side. The opposite side (−Y side) in the horizontal direction Y that is opposite to the side to which the arrowhead of the Y-axis faces is referred to as the right side. The side (+Z side) in the vertical direction Z to which the Z-axis arrowhead faces is referred to as the upper side. The side (−Z side) in the vertical direction Z that is opposite to the side to which the arrowhead of the Z axis faces is referred to as the lower side. In the first embodiment, the vertical direction Z corresponds to the “predetermined direction”, the upper side corresponds to the “first side”, and the lower side corresponds to the “second side”.
As shown in FIG. 2 and FIG. 3 , the heat exchanger 13 includes a heat exchanger main body 50, a first collecting pipe 51, a second collecting pipe 52, a first port portion 53, and a second port portion 54. The heat exchanger main body 50 is a part where the heat exchange between the refrigerant 40 and air is performed. The heat exchanger 13 can perform the heat exchange between the refrigerant 40 flowing inside the heat exchanger main body 50 and the air passing through the heat exchanger main body 50. The heat exchanger main body 50 has a plurality of heat transmission pipes 55, first heat transmission fins 56, protective members 57, 58, and second heat transmission fins 59 a, 59 b.
The refrigerant 40 flows inside the plurality of heat transmission pipes 55. The plurality of heat transmission pipes 55 are arranged side by side in the vertical direction Z. The plurality of heat transmission pipes 55 are arranged along the vertical direction Z at regular intervals therebetween. The heat transmission pipe 55 is a tubular member extending in the left-right direction Y. For example, a material forming the heat transmission pipe 55 is the aluminum or an aluminum alloy. The heat transmission pipes 55 are open on both sides in the left-right direction Y. In the first embodiment, the dimension of the heat transmission pipe 55 in the vertical direction Z is smaller than the dimension of the heat transmission pipe 55 in the front-rear direction X. In the first embodiment, the heat transmission pipes 55 are flat pipes.
The plurality of heat transmission pipes 55 include a plurality of first heat transmission pipes 55 a and a plurality of second heat transmission pipes 55 b. The plurality of second heat transmission pipes 55 b are located at the lower side of the plurality of first heat transmission pipes 55 a. In the first embodiment, the plurality of second heat transmission pipes 55 b are arranged adjacent to and below the plurality of first heat transmission pipes 55 a. In the first embodiment, four first heat transmission pipes 55 a and four second heat transmission pipes 55 b are provided. In the first embodiment, a total of eight heat transmission pipes 55 are provided, including the four first heat transmission pipes 55 a and the four second heat transmission pipes 55 b. In the first embodiment, the uppermost heat transmission pipe 55 among the plurality of heat transmission pipes 55 is the first heat transmission pipe 55 a. In the first embodiment, the lowest heat transmission pipe 55 among the plurality of heat transmission pipes 55 is the second heat transmission pipe 55 b.
The direction of flow of the refrigerant 40 inside each of the first heat transmission pipes 55 a is the same with each other. The direction of flow of the refrigerant 40 inside each of the second heat transmission pipes 55 b is the same with each other. In the first embodiment, the direction of flow of the refrigerant 40 inside the second heat transmission pipe 55 b is opposite to the direction of flow of the refrigerant 40 inside the first heat transmission pipe 55 a.
The first heat transmission fins 56 are provided between the heat transmission pipes 55 that are adjacent to each other in the vertical direction Z. That is, seven first heat transmission fins 56 are provided in the first embodiment. Each first heat transmission fin 56 connects heat transmission pipes 55 adjacent to each other in the vertical direction Z. Both ends of each first heat transmission fin 56 in the vertical direction Z are fixed to the heat transmission pipes 55 adjacent to each other in the vertical direction Z by, for example, brazing. The plurality of heat transmission pipes 55 are connected to each other by the plurality of first heat transmission fins 56.
In the first embodiment, the first heat transmission fins 56 are corrugated fins extending along the left-right direction Y in which the heat transmission pipes 55 extend. The first heat transmission fin 56 has a wave shape proceeding in the left-right direction Y when viewed in the front-rear direction X. The dimension of the first heat transmission fins 56 in the left-right direction Y is slightly smaller than the dimension of the heat transmission pipes 55 in the left-right direction Y. A material forming the first heat transmission fins 56 is, for example, the aluminum or the aluminum alloy.
The protective members 57, 58 are arranged on both sides of the plurality of heat transmission pipes 55 in the vertical direction Z, respectively. The protective member 57 is arranged side by side at the upper side of the plurality of heat transmission pipes 55. The protective member 58 is arranged side by side at the lower side of the plurality of heat transmission pipes 55. The upper surface of the protective member 57 is the upper surface of the heat exchanger main body 50. In other words, the protective member 57 configures the end portion at the upper side of the heat exchanger main body 50. The lower surface of the protective member 58 is the lower surface of the heat exchanger main body 50. In other words, the protective member 58 configures the end portion of at the lower side of the heat exchanger main body 50.
In the first embodiment, the protective members 57, 58 are tubular members extending in the same direction as the heat transmission pipe 55, that is, in the left-right direction Y. The protective members 57, 58 are open on both sides in the left-right direction Y. The shapes of the protective members 57, 58 in a cross section perpendicular to the left-right direction Y in which the protective members 57, 58 extend are the same as the shape of the heat transmission pipe 55 in the cross section perpendicular to the left-right direction Y in which the heat transmission pipe 55 extends. That is, in the first embodiment, the dimension of the protective members 57, 58 in the vertical direction Z is smaller than the dimension of the protective members 57, 58 in the front-rear direction X. In the first embodiment, the protective members 57, 58 are flat pipes having the same cross-sectional shape as that of the heat transmission pipe 55. The dimensions of the protective members 57, 58 in the left-right direction Y are slightly smaller than the dimension of the heat transmission pipe 55 in the left-right direction Y.
The second heat transmission fins 59 a are positioned between the protective member 57 and the uppermost heat transmission pipe 55 among the plurality of heat transmission pipes 55 in the vertical direction Z. The second heat transmission fins 59 a connect the protective member 57 and the uppermost heat transmission pipe 55. In the first embodiment, the second heat transmission fins 59 a connect the protective member 57 and the first heat transmission pipe 55 a located at the uppermost side among the plurality of first heat transmission pipes 55 a. The second heat transmission fins 59 a are fixed to the protective member 57 and the heat transmission pipes 55 by, for example, brazing.
The second heat transmission fins 59 b are positioned between the protective member 58 and the lowermost heat transmission pipe 55 among the plurality of heat transmission pipes 55 in the vertical direction Z. The second heat transmission fins 59 b connect the protective member 58 and the heat transmission pipe 55 positioned at the lowermost side. In other words, in the first embodiment, the second heat transmission fins 59 b connect the protective member 58 and the second heat transmission pipe 55 b located at the lowermost side among the plurality of second heat transmission pipes 55 b. The second heat transmission fins 59 b are fixed to the protective member 58 and the heat transmission pipes 55 by, for example, brazing.
The shapes of the second heat transmission fins 59 a, 59 b are the same as the shapes of the first heat transmission fins 56. That is, the second heat transmission fins 59 a, 59 b are corrugated fins extending along the left-right direction Y along which the protective members 57, 58 and the heat transmission pipes 55 extend. The second heat transmission fins 59 a, 59 b have a wave shape proceeding in the left-right direction Y when viewed in the front-rear direction X. The dimensions of the second heat transmission fins 59 a, 59 b in the left-right direction are slightly smaller than the dimension of the heat transmission pipe 55 in the left-right direction Y and substantially the same as the dimensions of the protective members 57, 58 in the left-right direction Y. The dimensions of the second heat transmission fins 59 a, 59 b in the left-right direction Y is the same as the dimension of the first heat transmission fin 56 in the left-right direction Y. A material forming the second heat transmission fins 59 a, 59 b is, for example, the aluminum or the aluminum alloy.
The first collecting pipe 51 is a tubular member extending in the vertical direction Z. The first collecting pipe 51 is substantially cylindrical. Both end portions of the first collecting pipe 51 in the vertical direction Z are blocked. The first collecting pipe 51 is located on the right side (−Y side) of the heat exchanger main body 50. The first collecting pipe 51 protrudes to both sides in the vertical direction Z from the heat exchanger main body 50. That is, the end portion at the upper side of the heat exchanger main body 50 is positioned at the lower side of the end portion at the upper side of the first collecting pipe 51. The end portion at the lower side of the heat exchanger main body 50 is located at the upper side of the end portion at the lower side of the first collecting pipe 51.
An end portion of the plurality heat transmission pipes 55 is connected to the first collecting pipe 51. In the first embodiment, the end portion at the right side (−Y side) of the plurality of heat transmission pipes 55 is connected to a wall portion at the left side (+Y side) of the first collecting pipe 51. The first collecting pipe 51 includes a first connection portion 51 a, a second connection portion 51 b, and a partition wall portion 51 c. In the first embodiment, the first connection portion 51 a is the upper portion of the first collecting pipe 51. The second connection portion 51 b is the lower portion of the first collecting pipe 51. The end portion at the right side of the plurality of first heat transmission pipes 55 a is connected to the first connection portion 51 a. The end portion of at the left side of the plurality of second heat transmission pipes 55 b is connected to the second connection portion 51 b.
An internal space S1 of the first connection portion 51 a and an internal space S2 of the second connection portion 51 b are partitioned in the vertical direction Z by the partition wall portion 51 c. In other words, the partition wall portion 51 c divides the internal space of the first collecting pipe 51 into two as the internal space S1 and the internal space S2 in the vertical direction Z. The internal space S1 is a portion of the interior of the first collecting pipe 51 located at the upper side of the partition wall portion 51 c. The internal space S2 is a portion of the interior of the first collecting pipe 51 located at the lower side of the partition wall portion 51 c.
The end portion at the right side (−Y side) of the plurality of heat transmission pipes 55 is open inside the first collecting pipe 51. More specifically, the end portion of the plurality of first heat transmission pipes 55 a is open to the internal space S1 of the first connection portion 51 a. The end portion of the plurality of second heat transmission pipes 55 b is open to the internal space S2 of the second connection portion 51 b.
The second collecting pipe 52 is a tubular member extending in the vertical direction Z. The second collecting pipe 52 is substantially cylindrical. Both end portions of the second collecting pipe 52 in the vertical direction Z are blocked. The second collecting pipe 52 is located at the left side (+Y side) of the heat exchanger main body 50. The second collecting pipe 52 protrudes to both sides in the vertical direction Z from the heat exchanger main body 50. That is, the end portion at the upper side of the heat exchanger main body 50 is positioned at the lower side of the end portion at the upper side of the second collecting pipe 52. The end portion at the lower side of the heat exchanger main body 50 is positioned at the upper side of the end portion at the lower side of the second collecting pipe 52. The position at the end portion at the upper side of the second collecting pipe 52 in the vertical direction Z is the same as the position of the end portion at the lower side of the first collecting pipe 51 in the vertical direction Z. The position of the end portion at the lower side of the second collecting pipe 52 in the vertical direction Z is the same as the position of the end portion at the lower side of the first collecting pipe 51 in the vertical direction Z.
The other end portion of the plurality of heat transmission pipes 55 is connected to the second collecting pipe 52. In the first embodiment, the end portion at the left side (+Y side) of the plurality of heat transmission pipes 55 is connected to the wall portion at the right side (−Y side) of the second collecting pipe 52. As shown in FIG. 3 , different from the first collecting pipe 51, the inside of the second collecting pipe 52 is not partitioned in the vertical direction Z according to the first embodiment. The end portion at the left side of the plurality of heat transmission pipes 55 is open inside the second collecting pipe 52. In other words, the end portion at the left side of the plurality of first heat transmission pipes 55 a and the end portion at the left side of the plurality of second heat transmission pipes 55 b are open inside the second collecting pipe 52. As a result, the internal space S1 of the first connection portion 51 a and the internal space S2 of the second connection portion 51 b are connected with each other via the interior of the plurality of first heat transmission pipes 55 a, the second collecting pipe 52, and the interior of the plurality of second heat transmission pipes 55 b.
In the first embodiment, the first port portion 53 and the second port portion 54 are tubular members extending in the left-right direction Y. The first port portion 53 and the second port portion 54 are connected to the wall portion at the right side (−Y side) of the first collecting pipe 51. The first port portion 53 is located at the upper side of the second port portion 54 in the vertical direction Z.
The end portion at the left side (+Y side) of the first port portion 53 opens into the internal space S1 of the first connection portion 51 a. The inside of the first port portion 53 is communicated with the inside of the plurality of first heat transmission pipes 55 a via the internal space S1 of the first connection portion 51 a. That is, the first connection portion 51 a connects the inside of the plurality of first heat transmission pipes 55 a and the inside of the first port portion 53.
The end portion at the left side (+Y side) of the second port portion 54 opens into the internal space S2 of the second connection portion 51 b. The inside of the second port portion 54 is communicated with the inside of the plurality of second heat transmission pipes 55 b via the internal space S2 of the second connection portion 51 b. That is, the second connection portion 51 b connects the inside of the plurality of second heat transmission pipes 55 b and the inside of the second port portion 54.
In this manner, in the first embodiment, the first port portion 53 and the second port portion 54 are communicated with the heat exchanger main body 50 via the first collecting pipe 51. As shown in FIG. 1 , the first port portion 53 is connected to the four-way valve 16 by a part of the circulation path portion 30. The second port portion 54 is connected to the flow adjustment valve 14 by a part of the circulation path portion 30.
The flow rate adjustment valve 14 can adjust the flow rate of the refrigerant 40 flowing inside the circulation path portion 30. The flow rate adjustment valve 14 is an expansion valve that reduces the pressure of the refrigerant 40 flowing inside the circulation path portion 30. The flow regulating valve 14 adjusts the flow rate of the refrigerant 40 and the pressure of the refrigerant 40 by adjusting the opening degree of thereof by the controller 17, for example. The opening degree of the flow rate adjustment valve 14 is adjusted according to the operating conditions of the indoor unit 20, for example.
The blower fan 15 generates an air flow that passes through the heat exchanger 13 and sends the air that the heat exchange with the refrigerant 40 has been performed to the outside of the outdoor unit 10. The blower fan 15 suctions the outdoor air into the outdoor unit housing 11 from the rear side (−X side) of the outdoor unit housing 11. The air suctioned into the outdoor unit housing 11 passes through the heat exchanger main body 50 from the rear side to the front side (+X side), and the heat exchange with the refrigerant 40 is performed at that time. The blower fan 15 sends the air after the heat exchange to the outside of the outdoor unit 10 from an air outlet that is not shown in figures. The blower fan 15 may be any type of fan. For example, the blower fan 15 is a propeller fan.
The four-way valve 16 is provided in a portion of the circulation path portion 30 that is connected to the discharge side of the compressor 12. The four-way valve 16 can reverse the direction of the refrigerant 40 flowing through the circulation path portion 30 by switching a part of the circulation path portion 30. When the path connected by the four-way valve 16 is the path indicated by the solid line in the four-way valve 16 in FIG. 1 , the refrigerant 40 flows in the circulation path portion 30 in the direction indicated by the arrowhead of the solid line as shown in FIG. 1 . On the other hand, when the path connected by the four-way valve 16 is the path indicated by the dashed line in the four-way valve 16 as shown in FIG. 1 , the refrigerant 40 flows in the circulation path portion 30 in the direction indicated by the arrowhead of the dashed line in FIG. 1 .
The controller 17 controls each part of the outdoor unit 10. The controller 17 is, for example, a system controller that controls the entire refrigeration cycle device 100. The controller 17 causes the refrigeration cycle device 100 to perform a defrosting operation for removing the frost generated in the heat exchanger 13 based on the temperature acquired by the temperature detection device 60, which will be described later. The defrosting operation will be detailed later.
In the first embodiment, the indoor unit 20 is capable of performing a cooling operation for cooling the air in the room in which the indoor unit 20 is arranged and a heating operation for warming the air in the room in which the indoor unit 20 is arranged. The indoor unit 20 has an indoor unit housing 21, a heat exchanger 22 and a blower fan 23. The heat exchanger 22 and the blower fan 23 are accommodated inside the indoor unit housing 21. Although not shown in figures, the indoor unit housing 21 has an outlet port and a suction port that open into the room in which the indoor unit 20 is arranged.
The heat exchanger 22 is provided in a portion of the circulation path portion 30 located inside the indoor unit housing 21. The heat exchanger 22 performs the heat exchange between the refrigerant 40 flowing inside the circulation path portion 30 and the indoor air suctioned into the indoor unit housing 21. The heat exchanger 22 may have any structure as long as it can perform the heat exchange between the refrigerant 40 and the air inside the room. The structure of the heat exchanger 22 may be the same as the structure of the heat exchanger 13 of the outdoor unit 10 or may be different from the structure of the heat exchanger 13.
The blower fan 23 suctions the air inside the room into the indoor unit housing 21 through an air the suction port that is not shown in figures provided in the indoor unit housing 21. The air suctioned into the indoor unit housing 21 passes through the heat exchanger 22 and performs the heat exchange with the refrigerant 40 at that time. The blower fan 23 sends the air after the heat exchange to the outside of the indoor unit 20 from an outlet port that is not shown in figures provided in the indoor unit housing 21. As a result, the air that the heat exchange with the refrigerant 40 has been performed by the heat exchanger 22 is blown into the room from the outlet port. The blower fan 23 may be any type of blower. The blower fan 23 may be the same type as the blower fan 15 of the outdoor unit 10 or may be of a different type from the blower fan 15. For example, the blower fan 23 is a cross-flow fan.
When the indoor unit 20 is operated in the cooling operation, the refrigerant 40 flowing through the circulation path portion 30 flows in the direction indicated by the arrowhead of the solid line as in FIG. 1 . That is, when the indoor unit 20 is operated in the cooling operation, the refrigerant 40 flowing through the circulation path portion 30 is circulated so as to flow through the compressor 12, the heat exchanger 13 of the outdoor unit 10, the flow rate adjustment valve 14, and the heat exchanger 22 of the indoor unit 20 in this sequence and then returns to the compressor 12. In the cooling operation, the refrigerant 40 that is compressed by the compressor 12 to become into the high-temperature, high-pressure gas flows into the heat exchanger 13 of the outdoor unit 10. The refrigerant 40 that has flowed into the heat exchanger 13 exchanges heat with the air suctioned into the outdoor unit housing 11 by the blower fan 15. As a result, in the heat exchanger 13, the heat of the refrigerant 40 is discharged to the air inside the outdoor unit housing 11, and the refrigerant 40 condenses into a liquid. The refrigerant 40 that becomes into the liquid in the heat exchanger 13 flows into the heat exchanger 22 of the indoor unit 20. During the period while the refrigerant 40 flows from heat exchanger 13 to heat exchanger 22, the pressure of the refrigerant 40 is reduced by the flow rate adjustment valve 14 as an expansion valve.
The refrigerant 40 that has flowed into the heat exchanger 22 performs the heat exchange with the air inside the indoor unit 20. In the heat exchanger 22, the refrigerant 40 takes heat from the air suctioned into the indoor unit housing 21 by the blower fan 23 and evaporates. The air from which the heat thereof is taken by the refrigerant 40 to be cooled is discharged into the room from the air outlet port that is not shown in figures by the blower fan 23. Accordingly, the air inside the room can be cooled.
The refrigerant 40 that has evaporated in the heat exchanger 22 to become the low-temperature, low-pressure gas, passes through the four-way valve 16 and flows into the compressor 12 of the outdoor unit 10. The refrigerant 40 is compressed in the compressor 12 and becomes the high-temperature, high-pressure gas again. The refrigerant 40 that has become the high-temperature, high-pressure gas flows into the heat exchanger 13 of the outdoor unit 10 again. In the cooling operation, the heat exchanger 13 inside the outdoor unit 10 functions as a condenser, and the heat exchanger 22 inside the indoor unit 20 functions as an evaporator.
On the other hand, when the indoor unit 20 is operated in the heating operation, the refrigerant 40 flowing inside the circulation path portion 30 flows in the direction indicated by the dashed line in FIG. 1 . In other words, when the indoor unit 20 is operated in the heating operation, the refrigerant 40 flowing inside the circulation path portion 30 is circulated to flow through the compressor 12, the heat exchanger 22 of the indoor unit 20, the flow rate adjustment valve 14, and the heat exchanger 13 of the outdoor unit 10 in this sequence, and then return to the compressor 12. In the heating operation, the refrigerant 40 that is compressed by the compressor 12 in the outdoor unit 10 to become the high-temperature and high-pressure gas flows into the heat exchanger 22 of the indoor unit 20. The refrigerant 40 that has flowed into the heat exchanger 22 performs the heat exchange in the heat exchanger 22 with the air suctioned into the indoor unit housing 21 by the blower fan 23. As a result, in the heat exchanger 22, the heat of the refrigerant 40 is discharged to the air inside the indoor unit housing 21, and the refrigerant 40 condenses into the liquid. The air to which the heat of the refrigerant 40 is discharged and warmed is discharged to the room from an outlet portion that is not shown in figures by the blower fan 23. As a result, the warm air is discharged to the inside of the room, and the air in the room can be warmed.
The refrigerant 40 that has been liquefied in the heat exchanger 22 flows into the heat exchanger 13 of the outdoor unit 10. During the period while the refrigerant 40 flows from the heat exchanger 22 to the heat exchanger 13, the pressure of the refrigerant 40 is reduced by the flow rate adjustment valve 14 as an expansion valve. The refrigerant 40 that has flowed into the heat exchanger 13 exchanges heat with the air inside the outdoor unit 10. In the heat exchanger 13, the refrigerant 40 takes the heat from the air suctioned into the outdoor unit housing 11 by the blower fan 15 and then evaporates. The air in the outdoor unit housing 11 from which the heat thereof has been taken by the refrigerant 40 is discharged to the outside of the room from the outlet port that is not shown in figures by the blower fan 15.
The refrigerant 40 that has evaporated and become the low-temperature, low-pressure gas in the heat exchanger 13 is compressed in the compressor 12 to become the high-temperature, high-pressure gas again. The refrigerant 40 that has become the high-temperature, high-pressure gas flows into the heat exchanger 22 of the indoor unit 20 again. In the heating operation, the heat exchanger 13 inside the outdoor unit 10 functions as the evaporator, and the heat exchanger 22 inside the indoor unit 20 functions as the condenser.
As shown in FIG. 2 and FIG. 3 , the refrigeration cycle device 100 further includes a temperature detection device 60 attached to the heat exchanger 13 of the outdoor unit 10. The temperature detection device 60 may be any type of temperature detection device as long as it can detect the temperature of the portion of the heat exchanger 13 to which the temperature detection device 60 is attached. The temperature detection device 60 is, for example, a thermistor. The temperature detection device 60 is attached to the end portion at the lower side of the heat exchanger main body 50. In the first embodiment, the temperature detection device 60 is attached to the end portion at the right side (−Y side) on the lower surface of the protective member 58. In other words, in the first embodiment, the temperature detection device 60 is attached to the end portion near the second port portion 54 side in the end portion at the lower side of the heat exchanger main body 50.
Next, the defrosting operation will be explained. The defrosting operation is performed for removing the frost generated in the heat exchanger 13. During the heating operation described above, the refrigerant 40 flowing through the plurality of heat transmission pipes 55 in the heat exchanger 13 of the outdoor unit 10 functioning as the evaporator takes the heat from the air contacting the heat exchanger main body 50. Accordingly, the temperature of the heat exchanger main body 50 decreases during the heating operation. In this case, for example, when the outdoor temperature in the outdoor where the outdoor unit 10 is arranged is relatively low and the outdoor air humidity in the outdoor is relatively high, the moisture in the air contacting the heat exchanger main body 50 reaches the dew point temperature so as to condense and adheres to the surface of the heat exchanger main body 50. When the temperature of the moisture adhering to the surface of the heat exchanger main body 50 becomes lower than the freezing point, the water solidifies and becomes the frost. In the first embodiment, the surface of the heat exchanger main body 50 includes the surface of the heat transmission pipes 55, the surface of the first heat transmission fins 56, the surface of the second heat transmission fins 59 a, 59 b, and the surfaces of the protective members 57, 58.
When the frost accumulates on the surface of the heat exchanger main body 50, the space between the heat transmission pipes 55, and the space between the heat transmission pipes 55 and the protective members 57, 58 is filled by the frost such that it is difficult for the air to pass through the heat exchanger main body 50. Therefore, the heat exchange efficiency between the refrigerant 40 flowing through the plurality of heat transmission pipes 55 and the air may decrease, and the heating capacity in the heating operation may decrease. Therefore, in a case in which the heating operation is to be continued for a certain period of time, it is necessary to periodically perform the defrosting operation as a reverse cycle of the heating operation, to remove the frost formed on the heat exchanger 13.
In the defrosting operation, the direction of the refrigerant 40 flowing in the circulation path portion 30 is the same as the direction of the refrigerant 40 flowing in the circulation path portion 30 during the cooling operation. In the defrosting operation, similar to the cooling operation, the heat exchanger 13 inside the outdoor unit 10 functions as the condenser, and the heat exchanger 22 inside the indoor unit 20 functions as the evaporator. In FIG. 3 , the direction of the refrigerant 40 flowing therethrough that is indicated by the arrowhead is the direction of the flow of the refrigerant 40 during the defrosting operation or the cooling operation. As shown in FIG. 3 , during the defrosting operation and the cooling operation according to the first embodiment, the refrigerant 40 that has flowed into the internal space S1 of the first collecting pipe 51 from the first port portion 53 flows into the plurality of first heat transmission pipes 55 a from the right side (−Y side). The refrigerant 40 that has flowed into the plurality of first heat transmission pipes 55 a flows toward the left side (+Y side) inside each first heat transmission pipe 55 a and flows into the second collecting pipe 52. That is, the refrigerant 40 flowing inside the plurality of first heat transmission pipes 55 a joins inside the second collecting pipe 52.
The refrigerant 40 that has flowed into the second collecting pipe 52 flows into the plurality of second heat transmission pipes 55 b from the left side (+Y side). As described above, during the defrosting operation according to the first embodiment, the refrigerant 40 flows into the plurality of second heat transmission pipes 55 b after flowing through the plurality of first heat transmission pipes 55 a. The refrigerant 40 that has flowed into the plurality of second heat transmission pipes 55 b flows to the right side (−Y side) inside each second heat transmission pipe 55 b and flows into the internal space S2 of the first collecting pipe 51. That is, the refrigerant 40 flowing inside the plurality of second heat transmission pipes 55 b joins in the internal space S2. The refrigerant 40 that has flowed into the internal space S2 flows out of the heat exchanger 13 through the second port portion 54.
As described above, during the defrosting operation and the cooling operation, the refrigerant 40 that has flowed into the heat exchanger 13 from the first port portion 53 flows into the plurality of heat transmission pipes 55, and the refrigerant 40 that has flowed into the heat transmission pipes 55 flows out of the heat exchanger 13 through the second port portion 54. During the heating operation, the direction in which the refrigerant 40 flows inside the heat exchanger 13 is opposite to that during the defrosting operation and the cooling operation. That is, during the heating operation, the refrigerant 40 that has flowed into the heat exchanger 13 from the second port portion 54 flows into the plurality of heat transmission pipes 55, and the refrigerant 40 that has flowed into the plurality of heat transmission pipes 55 flows out of the heat exchanger 13 from the first port portion 53.
In a case in which the refrigerant 40 flows as in the defrosting operation and the cooling operation described above, the refrigerant 40 having a relatively high temperature flows into the plurality of heat transmission pipes 55 in the heat exchanger 13, and the refrigerant 40 flowing inside of the plurality of heat transmission pipes 55 contacts the heat exchanger main body 50 to discharge the heat to the air. Therefore, by flowing the refrigerant 40 during the defrosting operation in the same direction as that during the cooling operation, it is possible to melt and remove the frost generated on the surface of the heat exchanger main body 50 by the heat discharged from the refrigerant 40 flowing in the plurality of heat transmission pipes 55.
The controller 17 causes the refrigeration cycle device 100 to perform the defrosting operation based on the temperature acquired by the temperature detection device 60. Specifically, for example, in a case in which a state when the temperature detected by the temperature detection device 60 remains lower than a first temperature for a period equal to or longer than a predetermined period, the controller 17 determines that it is possible that the frost has generated on the surface of the heat exchanger main body 50 and causes the refrigerating cycle device 100 to perform the defrosting operation. The first temperature is, for example, a temperature within a range between −5° C. and 0° C.
On the other hand, during the defrosting operation, in a case in which a state when the temperature acquired by the temperature detection device 60 becomes equal to or higher than a second temperature, the controller 17 determines that all the frost generated on the surface of the heat exchanger main body 50 has been removed and then terminates the defrosting operation. The second temperature is, for example, a temperature within the range between 5° C. and 10° C. It should be noted that the second temperature corresponds to the “predetermined temperature” in the first embodiment. During the defrosting operation, the refrigerant 40 flowing inside the plurality of heat transmission pipes 55 discharges the heat to melt the frost such that the temperature of the refrigerant 40 decreases while flowing from the first port portion 53 to the second port portion 54. Therefore, when the frost still remains, the temperature of the refrigerant 40 when reaching the second port portion 54 is relatively low. On the other hand, when the frost is completely removed, the heat of the refrigerant 40 is not used for melting the frost such that the temperature of the refrigerant 40 when reaching the second port portion 54 becomes higher than the state when the frost remains. Therefore, the controller 17 can detect whether the frost is remained or not by detecting the temperature of the heat exchanger 13 on the downstream side in the flow direction of the refrigerant 40 in the heat exchanger 13, that is, on the side close to the second port portion 54, by the temperature detection device 60.
During the defrosting operation according to the first embodiment, the refrigerant 40 flows into the plurality of first heat transmission pipes 55 a at the upper side at first before flowing into the plurality of second heat transmission pipes 55 b at the lower side. Accordingly, when the defrosting operation is started, the frost adhering to the surface of the plurality of first heat transmission pipes 55 a, the surface of the first heat transmission fins 56 connected to the plurality of first heat transmission pipes 55 a, the surface of the second heat transmission fins 59 a, and the surface of the protective member 57 are melted at first.
When the frost adhering to the plurality of first heat transmission pipes 55 a and the like melts, the refrigerant 40 having the relatively high temperature also flows into the plurality of second heat transmission pipes 55 b such that the frost adhering to the surface of the second heat transmission pipes 55 b, the surface of the first heat transmission fins 56 connected to the plurality of second heat transmission pipes 55 b, the surface of the second heat transmission fins 59 b, and the surface of the protective member 58 are also melted sequentially. At this time, the frost adhering to the surfaces of the plurality of second heat transmission pipes 55 b and the like melts in order from the upper side thereof near the first heat transmission pipes 55 a where the frost has already melted and the temperature is relatively high. Therefore, the frost formed on the surface of the heat exchanger main body 50 tends to remain on the lower end portion of the heat exchanger main body 50 to the end. That is, in the heat exchanger main body 50 having a plurality of heat transmission pipes 55 arranged side by side in a predetermined direction (vertical direction Z), it is easy for the frost to remain to the end in the end portion positioned at the side (lower side) at which the second port portion 54 from which the refrigerant 40 flows out during the defrosting operation is positioned with respect to the first port portion 53 into which the refrigerant 40 flows into during the defrosting operation.
Here, for example, a case of detecting the temperature in the portion where the refrigerant 40 flowing in the plurality of second heat transmission pipes 55 b has joined such as the portion communicating the heat exchanger 13 and the flow rate adjustment valve 14 in the second port portion 54 or the circulation path portion 30 or the like and terminating the defrosting operation when the detected temperature is equal to or higher than the second temperature will be considered. In this case, the detected temperature is the temperature based on the temperature of the refrigerant 40 that joins from inside the plurality of second heat transmission pipes 55 b. However, as described above, the frost adhering to the surfaces of the plurality of second heat transmission pipes 55 b and the like melts sequentially from the upper side. Therefore, before all the frost is removed, the temperature of the refrigerant 40 flowing inside the second heat transmission pipes 55 b located on the upper side is relatively high, and the temperature of the refrigerant 40 flowing inside the second heat transmission pipes 55 b located on the lower side becomes relatively low. As a result, there is a case in which the temperature of the joined refrigerant 40 becomes relatively high due to the refrigerant 40 flowing inside the second heat transmission pipes 55 b positioned on the upper side. Accordingly, there is a case in which the detected temperature is equal to or higher than the second temperature and the defrosting operation is terminated before the frost formed on the surface of the second heat transmission pipes 55 b located on the lower side is removed. In this case, the frost continues to accumulate on the surface of the second heat transmission pipes 55 b located on the lower side, and the accumulated frost may crush and damage the second heat transmission pipes 55 b.
In comparison, it is possible to suppress the frost from remaining if the defrosting operation is performed even if the detected temperature becomes equal to or higher than the second temperature for a while. However, in that case, the defrosting operation execution time tends to become longer than necessary, and the time during which the heating operation cannot be executed becomes longer. Therefore, the convenience for the user who uses the refrigeration cycle device 100 is decreased. Also, during the defrosting operation, the blower fan 23 in the indoor unit 20 is stopped so as not to send the low-temperature air into the room. Therefore, the refrigerant 40 does not vaporize in the heat exchanger 22 of the indoor unit 20 and the refrigerant 40 in the liquid state flows into the compressor 12. Therefore, the compression amount of the refrigerant 40 in the compressor 12 increases, and there is a possibility that the compressor 12 may be damaged. Also, the concentration of lubricating oil in the compressor 12 may decrease, and the seizure may occur in sliding portions in the compressor 12.
To address the problem shown above, according to the present embodiment, the temperature detection device 60 is attached to the end portion at the lower side of the heat exchanger main body 50, that is, to the end portion at the side where the second port portion 54 is located with respect to the first port portion 53. Therefore, it is possible to detect the temperature of a portion of the heat exchanger main body 50 where the refrigerant 40 flowing through the plurality of heat transmission pipes 55 is not joined and the frost tends to remain by the temperature detection device 60. Accordingly, it is suitable for the controller 17 to determine that all the frost has been removed based on the temperature acquired by the temperature detection device 60. Therefore, it is possible to prevent the frost from remaining when the defrosting operation ends. Accordingly, it is possible to suppress the continued accumulation of the frost on the portion at the lower side of the heat exchanger main body 50. As a result, it is possible to prevent the heat transmission pipes 55 from being damaged by the accumulated frost. Moreover, since the defrosting operation can be suitably terminated at the timing after all the frost has been removed, it is possible to suppress the execution time of the defrosting operation from becoming longer. As a result, it is possible to suppress the lengthening of the time during which the heating operation cannot be performed, and it is possible to suppress the decrease in the convenience for the user using the refrigeration cycle device 100. In addition, it is possible to suppress the increase in the compression amount of the refrigerant 40 in the compressor 12 so as to suppress the damage occurred in the compressor 12. In addition, it is possible to suppress the decrease in the concentration of the lubricating oil in the compressor 12 such that it is possible to suppress the occurrence of the seizure occurred in the sliding portion of the compressor 12.
Also, according to the first embodiment, the temperature detection device 60 is attached to the end portion at the lower side of the heat exchanger main body 50 that is close to the second port portion 54. The portion of the heat exchanger main body 50 that is closer to the second port portion 54 is located at the downstream side in the flow of the refrigerant 40 during the defrosting operation such that it is slow for the temperature to rise so as to melt the frost. Therefore, by attaching the temperature detection device 60 to the end portion of the heat exchanger main body 50 that is close to the second port portion 54 in the end portion at the lower side of the heat exchanger main body 50, it is possible to detect the temperature of the portion of the heat exchanger main body 50 where the frost is more likely to remain by the temperature detection device 60. Thus, it is possible to suppress the frost from remaining while suppressing the execution time of the defrosting operation from becoming longer by terminating the defrosting operation based on the temperature detected by the temperature detection device 60.
Also, according to the first embodiment, the heat exchanger main body 50 has the first heat transmission fins 56 that connect the heat transmission pipes 55 adjacent to each other in the vertical direction Z. The first heat transmission fins 56 are the corrugated fins extending along the left-right direction Y in which the heat transmission pipes 55 extend. Accordingly, the heat exchange efficiency in the heat exchanger main body 50 can be improved by the first heat transmission fins 56. Also, in the case in which such first heat transmission fins 56 are provided, it is difficult to arrange the temperature detection device 60 between the adjacent heat transmission pipes 55 due to the interference by the first heat transmission fins 56. In contrast, the temperature detection device 60 in the first embodiment is attached to the end portion at the lower side of the heat exchanger main body 50. Therefore, the temperature detection device 60 can be arranged without interfering with the first heat transmission fins 56. Also, there is no need to perform the processing such as drilling holes in the first heat transmission fins 56 or the like in order to attach the temperature detection device 60 thereto.
Also, according to the first embodiment, the dimension of the heat transmission pipe 55 in the vertical direction Z is smaller than the dimension of the heat transmission pipe 55 in the front-rear direction X orthogonal to both the left-right direction Y and the vertical direction Z in which the heat transmission pipe 55 extends. In a case in which the heat transmission pipes 55 are such flat pipes, it is easy to adopt the configuration in which the first collecting pipe 51 and the second collecting pipe 52 are provided and the plurality of heat transmission pipes 55 are connected to each other as in the first embodiment. Therefore, even if the temperature at the outlet port through which the refrigerant 40 flows out from the heat exchanger 13 is detected during the defrosting operation, that is, even if the temperature at the second port portion 54 in the first embodiment is detected, the temperature based on the temperature of the joined refrigerant 40 is detected as described above and it is likely to be difficult to suitably determine the timing when all the frost has been removed. In contrast, in the first embodiment, since the temperature detection device 60 is attached to the end portion at the lower side of the heat exchanger main body 50 as described above, it is possible to suitably determine the timing when all of the frost has been removed based on the temperature before the refrigerant 40 has joined. In this manner, the effect obtained by the structure in which the temperature detection device 60 is attached to the end portion at the lower side of the heat exchanger main body 50 is more likely to be obtained effectively due to the heat exchanger 13 in which the heat transmission pipes 55 are the flat pipes.
Also, according to the first embodiment, the heat exchanger 13 includes the first connection portion 51 a that connects the inside of the plurality of first heat transmission pipes 55 a and the inside of the first port portion 53, and the second connection portion 51 b that connects the inside of the plurality of second heat transmission pipes 55 b and the inside of the second port portion 54. During the defrosting operation, the refrigerant 40 flows into the multiple second heat transmission pipes 55 b after flowing through the multiple first heat transmission pipes 55 a. Therefore, as described above, it is more likely that the frost adhering on the surface of the second heat transmission pipes 55 b melts more slowly than the frost adhering on the surface of the first heat transmission pipes 55 a. Also, among the second heat transmission pipes 55 b, the further the second heat transmission pipes 55 b are positioned from the first heat transmission pipes 55 a, the slower the frost adhering to the surface thereof melts. Therefore, by attaching the temperature detection device 60 to the end portion at the lower side of the heat exchanger main body 50, it is possible to detect the temperature near the second heat transmission pipes 55 b where the frost is most likely to remain. As a result, by terminating the defrosting operation based on the temperature detected by the temperature detection device 60, it is possible to more suitably suppress the frost from remaining while suppressing the execution time of the defrosting operation from being longer.
Also, according to the first embodiment, the heat exchanger 13 includes the first collecting pipe 51 to which one end portion of the plurality of heat transmission pipes 55 is connected, and the second collecting pipe 51 to which the other end portion of the plurality of heat transmission pipes 55 is connected. The first collecting pipe 51 has the first connection portion 51 a and the second connection portion 51 b. Accordingly, the plurality of first heat transmission pipes 55 a and the plurality of second heat transmission pipes 55 b are suitably connected by the first collecting pipe 51 and the second collecting pipe 52 and the refrigerant 40 can suitably flow through each heat transmission pipe 55. Also, by providing the first connection portion 51 a and the second connection portion 51 b in the first collecting pipe 51, it is possible to arrange the first port portion 53 and the second port portion 54 on the same side in the left-right direction Y. Accordingly, the work of connecting the pipes to the first port portion 53 and the second port portion 54 of the heat exchanger 13 can be easily performed.
Also, according to the first embodiment, the heat exchanger main body 50 includes the protective member 58 arranged side by side on the lower side of the plurality of heat transmission pipes 55, and the second heat transmission fins 59 b connecting the protective member 58 and the heat transmission pipes 55. The temperature detection device 60 is attached to the surface at the lower side of the protective member 58. By providing the protective member 58 at the lower side of the plurality of heat transmission pipes 55, the lower side of the plurality of heat transmission pipes 55 can be protected by the protective member 58 from the lower side. Accordingly, even if in a case in which the heat exchanger main body 50 is subjected to an impact or the like from the lower side, the damage to the heat transmission pipes 55 can be suppressed. In the first embodiment, since the protective member 58 is positioned on the upper side of the end portion at the lower side of the first collecting pipe 51 and the end portion at the lower side of the second collecting pipe 52, it is difficult to apply a direct impact to the protective member 58 from the lower side, and it is possible to further suppress the damage to the heat transmission pipes 55. Also, since the second heat transmission fins 59 b are provided, it is more likely for the temperature of the protective member 58 to be close to the temperature of the heat transmission pipes 55 located at the lowest side among the plurality of heat transmission pipes 55. As a result, even if the protective member 58 is provided with the temperature detection device 60, it is possible to suitably determine the timing when all of the frost has been removed. Therefore, as the same as described above, it is possible to suppress the frost from remaining while suppressing the execution time of the defrosting operation from becoming longer. Also, the temperature of the protective member 58 tends to be lower than the temperature of the heat transmission pipes 55 located at the lowest side thereof. Therefore, by terminating the defrosting operation when the temperature of the protective member 58 becomes equal to or higher than the second temperature, it is possible to more suitably prevent the frost from remaining on the surfaces of the heat transmission pipes 55 and the like.
Also, according to the first embodiment, the protective member 58 is a tubular member. The shape of the protective member 58 in a cross section orthogonal to the left-right direction Y in which the protective member 58 extends is the same as the shape of the heat transmission pipe 55 in a cross section orthogonal to the left-right direction Y in which the heat transmission pipe 55 extends. Therefore, it is possible to manufacture the protective member 58 by using the tubular member as same as the tubular member forming the heat transmission pipe 55. Accordingly, the protective member 58 can be easily manufactured, and the manufacturing cost of the heat exchanger 13 can be reduced.
Also, according to the first embodiment, the predetermined direction in which the plurality of heat transmission pipes 55 are arranged is the vertical direction Z. The first side in the predetermined direction is the upper side in the vertical direction Z. The second side in the predetermined direction is the lower side in the vertical direction Z. When the plurality of heat transmission pipes 55 are arranged in the vertical direction Z in this way and when the frost melts on the surface of the heat transmission pipes 55 and the like at the upper side to become water, the water flows downward due to the gravity and the frost is formed on the surface of the heat transmission pipe 55 or the like positioned at the lower side. Accordingly, the frost formed on the surface of the heat exchanger main body 50 tends to melt in order from the upper side toward the lower side. In other words, it is more likely for the frost formed on the surface of the heat exchanger main body 50 in the end portion at the lower side tends to remain to the end. Accordingly, by attaching the temperature detection device 60 to the end portion at the lower side of the heat exchanger main body 50 to detect the temperature thereof, it is possible to more suitably determine the timing when all of the frost has been removed. Therefore, it is possible to further suppress the frost from remaining while suppressing the execution time of the defrosting operation from becoming longer.
Also, according to the first embodiment, the heat exchanger main body 50 includes the protective members 57 arranged side by side on the upper side of the plurality of heat transmission pipes 55, and the second heat transmission fins 59 a connecting the protective members 57 and the heat transmission pipes 55. By providing the protective members 57 at the upper side of the plurality of heat transmission pipes 55, the plurality of heat transmission pipes 55 can be protected by the protective member 57 from the upper side. Therefore, even if the heat exchanger main body 50 is subjected to an impact or the like from the upper side, it is possible to suppress the damage to the heat transmission pipes 55. In the first embodiment, since the protective member 57 is positioned at the lower side of the upper end portion of the first collecting pipe 51 and the upper end portion of the second collecting pipe 52, it is difficult to apply a direct impact to the protective member 57 from the upper side and it is possible to further suppress the damage to the heat transmission pipes 55. Also, the protective member 57 is a tubular member. The shape of the protective member 57 in a cross section orthogonal to the left-right direction Y in which the protective member 57 extends is the same as the shape of the heat transmission pipe 55 in a cross section orthogonal to the left-right direction Y in which the heat transmission pipe 55 extends. Accordingly, similar to the protective member 58, it is easy to manufacture the protective member 57, and the manufacturing cost of the heat exchanger 13 can be reduced.

Second Embodiment

FIG. 4 is a cross-sectional view showing a heat exchanger 213 of an outdoor unit 210 according to a second embodiment. As shown in FIG. 4 , the heat exchanger 213 according to the second embodiment differs from the heat exchanger 13 according to the first embodiment in that heat transmission pipes 55 are provided instead of the protective members 57, 58. In the following description of the second embodiment, the same configurations as those of the first embodiment described above may be omitted by appropriately designating with the same reference signs.
In the second embodiment, a heat exchanger main body 250 has a total of ten heat transmission pipes 55, including five first heat transmission pipes 55 a and five second heat transmission pipes 55 b. The heat transmission pipes 55 are connected to each other by the first heat transmission fins 56. In the heat exchanger main body 250, the first heat transmission pipes 55 a are provided in place of the protective members 57 in the first embodiment, and the second heat transmission pipes 55 b are provided in place of the protective members 58 in the first embodiment.
In the second embodiment, a temperature detection device 260 is attached to the heat transmission pipe 55 positioned at the lowermost side among the plurality of heat transmission pipes 55. More specifically, the temperature detection device 260 is attached to the end portion at the right side (−Y side) on the surface at the lower side of the second heat transmission pipe 55 b that is positioned at the lowermost side thereof. Other configurations of the heat exchanger 213 are the same as other configurations of the heat exchanger 13 according to the first embodiment. Other configurations of the outdoor unit 210 are the same as the other configurations of the outdoor unit 10 according to the first embodiment.
According to the second embodiment, the temperature detection device 260 is attached to the heat transmission pipe 55 that is positioned at the lowermost side among the plurality of heat transmission pipes 55. Therefore, the temperature detected by the temperature detection device 260 can be suitably approximated to the temperature of the refrigerant 40 flowing inside the heat transmission pipe 55 located at the lowermost side. Accordingly, the controller 17 can more suitably determine the timing when all of the frost has been removed based on the temperature detected by the temperature detection device 260. Therefore, it is possible to more suitably suppress the execution time of the defrosting operation from becoming longer.
Although the embodiments of the present disclosure have been described above, the present disclosure is not limited to the configurations of the embodiments described above, and the following configurations and methods can also be adopted.
The temperature detection device may be attached thereto at any position in the end portion at the second side (lower side) of the heat exchanger body. The temperature detection device may be attached to the central portion in the left-right direction Y in the end portion at the lower side of the heat exchanger main body 50, such as the temperature detection device 160 indicated by a two-dot chain line in FIG. 3 . A plurality of temperature detection devices may be provided. The temperature detection device may be attached to a member other than the heat transmission pipe and the protective member as long as being attached to the end portion at the second side of the heat exchanger main body.
The predetermined direction in which the plurality of heat transmission pipes are arranged is not particularly limited. The predetermined direction may be a direction intersecting the vertical direction. The number of the heat transmission pipes is not particularly limited as long as the number is equal to or more than two. The shape of the heat transmission pipe is not particularly limited. The heat transmission pipe may be a cylindrical pipe member.
The refrigerant may flow in any way through the plurality of heat transmission pipes during the period when flowing from the first opening portion to the second opening portion during the defrosting operation. The plurality of heat transmission pipes may include third heat transmission pipes positioned between the plurality of first heat transmission pipes and the plurality of second heat transmission pipes in a predetermined direction (vertical direction Z). In this case, the refrigerant may flow through the plurality of third heat transmission pipes after flowing through the plurality of first heat transmission pipes, and flow through the plurality of second heat transmission pipes after flowing through the plurality of third heat transmission pipes. During the defrosting operation in the above-described first embodiment and second embodiment, the refrigerant 40 may reciprocate for any number of times through the heat transmission pipes 55 between the first collecting pipe 51 and the second collecting pipe 52 during the period of flowing from the first port portion 53 to the second port portion 54. Depending on the number of times that the refrigerant 40 reciprocates between the first collecting pipe 51 and the second collecting pipe 52, a partition wall portion such as the partition wall portion 51 c is provided inside of the first collecting pipe 51 and the inside of the second collecting pipe 52.
As long as the first port portion is positioned at the first side (upper side) of the second port portion, the first port portion and the second port portion may be arranged in any manner. The first port portion may be provided on either of the first collecting pipe or the second collecting pipe, and the second port portion may be provided on the other of the first collecting pipe and the second collecting pipe.
The type of the first heat transmission fins and the type of the second heat transmission fins are not particularly limited. The shape of the first heat transmission fins and the shape of the second heat transmission fins are not particularly limited. The shape of the protective member is not particularly limited. The protective member may be a solid columnar member.
The controller may be provided anywhere in the refrigeration cycle device. The controller may be provided in the indoor unit, or may be provided in a portion of the refrigeration cycle device other than the outdoor unit and the indoor unit.
The refrigeration cycle device is not limited to an air conditioner as long as the refrigeration cycle device utilizes the refrigeration cycle in which the refrigerant circulates. The refrigeration cycle device may be a heat pump water heater or the like. As described above, each configuration and each method described in this specification can be appropriately combined as long as they do not contradict each other.

Claims

1. A refrigeration cycle device comprising:

an outdoor unit including a heat exchanger;

a temperature detection device attached to the heat exchanger; and

a controller that makes the refrigeration cycle device to perform a defrosting operation for removing frost generated in the heat exchanger based on temperature acquired by the temperature detection device,

wherein the heat exchanger comprises

a heat exchanger main body including a plurality of heat transmission pipes arranged side by side in a predetermined direction;

a first collecting pipe connected to a first end portion of the plurality of heat transmission pipes;

a second collecting pipe connected to a second end portion of the plurality of heat transmission pipes; and

a first port portion and a second port portion communicated with the heat exchanger main body via the first collecting pipe,

the first port portion is positioned at a first side of the second port portion in the predetermined direction,

the plurality of heat transmission pipes comprises

a plurality of first heat transmission pipes; and

a plurality of second heat transmission pipes positioned at a second side of the plurality of first heat transmission pipes in the predetermined direction,

the first collecting pipe comprises

a first connection portion communicating an inside of the plurality of first heat transmission pipes and an inside of the first port portion; and

a second connection portion communicating an inside of the plurality of second heat transmission pipes and an inside of the second port portion,

during the defrosting operation, refrigerant flowing to the inside of the heat exchanger from the first port portion flows to the inside of the plurality of first heat transmission pipes, the refrigerant flowing to the inside of the plurality of first heat transmission pipes flows to an inside of the plurality of second heat transmission pipes, and the refrigerant flowing to the inside of the plurality of second heat transmission pipes joins at the second connection portion and then flows out of the heat exchanger from the second port portion,

the temperature detection device is arranged at an upstream side of the second connection portion along a flow direction of the refrigerant during the defrosting operation and attached to an end portion in the heat exchanger main body at a second side in the predetermined direction, and

during the defrosting operation, the controller terminates the defrosting operation in a case in which the temperature acquired by the temperature detection device is equal to or higher than a predetermined temperature.

2. The refrigeration cycle device according to claim 1, wherein the temperature detection device is attached to an end portion that is close to the second port portion side among the end portions of the heat exchanger main body at the second side.

3. The refrigeration cycle device according to claim 1,

wherein the heat exchanger main body includes first heat transmission fins that connect the adjacent heat transmission pipes in the predetermined direction, and

the first heat transmission fins are corrugated fins extending in a direction along which the heat transmission pipes extend.

4. The refrigeration cycle device according to claim 1, wherein a dimension of the heat transmission pipes in the predetermined direction is smaller than a dimension of the heat transmission pipes in a direction orthogonal to both a direction in which the heat transmission pipes extend and the predetermined direction.

5. (canceled)

6. (canceled)

7. The refrigeration cycle device according to claim 1,

wherein the heat exchanger main body includes

a protective member arranged at the second side of the plurality of heat transmission pipes; and

second heat transmission fins that connect the protective member and the plurality of heat transmission pipes, and

the temperature detection device is attached to a surface at the second side of the protective member.

8. The refrigeration cycle device according to claim 7,

wherein the protective member is a tubular member, and

a shape of the protective member in a cross section orthogonal to a direction in which the protective member extends is same with a shape of the heat transmission pipe in a cross section orthogonal to a direction in which the heat transmission pipe extends.

9. The refrigeration cycle device according to claim 1, wherein the temperature detection device is attached to the heat transmission pipe positioned at the most second side among the plurality of heat transmission pipes.

10. The refrigeration cycle device according to claim 1,

wherein the predetermined direction is a vertical direction,

the first side is an upper side of the vertical direction, and

the second side is a lower side of the vertical direction.