JPWO2019155571A1 - Heat exchanger and refrigeration cycle equipment - Google Patents

Abstract

The heat exchanger includes a first heat exchanger including a plurality of first fins and a plurality of first heat transfer tubes fixed to the plurality of first fins and having ends connected to each other on one side, and a plurality of first heat exchangers. A second heat that includes two fins and a plurality of second heat transfer tubes that are fixed to a plurality of second fins and whose ends are connected to each other on one side, and are arranged in the air blowing direction with respect to the first heat exchange section. An exchange unit, a connecting member that connects the ends of the first straight tube of the plurality of first heat transfer tubes and the second straight tube of the plurality of second heat transfer tubes on the other side, and a plurality of first heat transfer tubes. Of the first header connected to the other end of the first long tube, which is longer than the first straight tube, and among the plurality of second heat transfer tubes, the length is longer than the second straight tube. It has a second header that is connected to the other end of the long second long pipe, and the connecting member is the end of the first fin and the second fin that are more than the first header and the second header. It is located on the side closer to the end.

Description

The present invention relates to a heat exchanger in which the refrigerant exchanges heat with air, and a refrigeration cycle device including the heat exchanger.

As a conventional heat exchanger, there is known a heat exchanger in which the length of the path from the inflow of the refrigerant to the outflow of the refrigerant is lengthened (see, for example, Patent Document 1). In the heat exchanger disclosed in Patent Document 1, the leeward heat exchange unit and the leeward heat exchange unit are classified into two upper and lower flow paths, and the upper flow path and the lower flow path are plurality. The flow direction of the refrigerant is opposite to that of the road. The first leeward header collecting pipe is provided with a plurality of connection pipes for connecting the plurality of upper flow paths and the plurality of lower flow paths of the leeward heat exchange unit.

In the heat exchanger disclosed in Patent Document 1, when the heat exchanger functions as a condenser, the refrigerant flows into a plurality of flow paths on the upper side of the upwind heat exchange unit, and then the second upwind header collecting pipe. And, it flows into a plurality of flow paths on the upper side of the leeward heat exchange unit via the second leeward header collecting pipe. Subsequently, when the refrigerant flows into the first leeward header collecting pipe, it flows into a plurality of flow paths below the leeward heat exchange unit via the plurality of connection pipes. After that, the refrigerant flows into the plurality of flow paths below the upwind heat exchange unit via the second leeward header collecting pipe and the second leeward header collecting pipe.

Japanese Patent No. 5679084

In the heat exchanger of Patent Document 1, since a plurality of connecting pipes for switching the flow direction of the refrigerant in opposite directions are provided on the outside of the first leeward header collecting pipe, the heat exchanger becomes large.

The present invention has been made to solve the above-mentioned problems, and provides a heat exchanger and a refrigeration cycle device that suppresses upsizing.

The heat exchanger according to the present invention has a plurality of first fins arranged along one direction, and a plurality of first heat transfer tubes fixed to the plurality of first fins and having ends connected to each other on one side. A first heat exchange unit including the above, a plurality of second fins arranged along the one direction, and a plurality of second fins fixed to the plurality of second fins and end portions connected to each other on one side. A second heat exchange section including a heat transfer tube and arranged in the air blowing direction with respect to the first heat exchange section, and a first straight tube and the plurality of second heat transfer tubes among the plurality of first heat transfer tubes. Of the connecting member that connects the ends of the second straight pipe to each other on the other side, and the first long pipe having a length in one direction longer than that of the first straight pipe among the plurality of first heat transfer tubes. A first header connected to the other end, and the other end of the second long tube having a length in one direction longer than the second straight tube among the plurality of second heat transfer tubes. It has a second header to be connected, and the connecting member is closer to the ends of the plurality of first fins and the ends of the plurality of second fins than the first header and the second header. It is located.

The refrigeration cycle device according to the present invention includes the above heat exchanger, a compressor that compresses and discharges the refrigerant, a throttle device that expands the refrigerant, and a load side in which the refrigerant exchanges heat with air in the air conditioning target space. It has a heat exchanger.

According to the present invention, the connecting member for switching the flow direction of the refrigerant in the opposite direction is located closer to the ends of the plurality of first fins and the ends of the plurality of second fins than the first header and the second header. Therefore, it is possible to prevent the heat exchanger from becoming large.

It is a refrigerant circuit diagram which shows one structural example of the refrigeration cycle apparatus including the heat exchanger of Embodiment 1 of this invention. It is a figure which shows the flow of the refrigerant when the refrigerating cycle apparatus shown in FIG. 1 performs a heating operation. It is an external perspective view which shows one configuration example of the heat exchanger shown in FIG. It is a side view of the heat exchanger shown in FIG. It is a side perspective view which shows the structural example of the header tube shown in FIG. It is a top view of the heat exchanger shown in FIG. It is a figure which shows the flow of the refrigerant in a heat exchanger at the time of a cooling operation. It is a figure which shows the flow of the refrigerant in a heat exchanger at the time of a heating operation. It is a schematic diagram for demonstrating the difference between the case where the 1st heat transfer tube shown in FIG. 1 is a flat tube, and the case where it is a circular tube. It is sectional drawing which shows the structural example when the 1st heat transfer tube shown in FIG. 3 is a flat tube. It is a schematic top view of the connection member shown in FIG. It is an external perspective view which shows one structural example of the heat exchanger of Embodiment 2 of this invention. It is a figure which shows the state of the refrigerant when the heat exchanger shown in FIG. 12 functions as a condenser. It is a schematic diagram for demonstrating the flow of a refrigerant about the heat exchanger of the comparative example. It is a schematic diagram for demonstrating the flow of a refrigerant about the heat exchanger shown in FIG. It is a figure explaining by comparing the case where the 1st heat transfer tube shown in FIG. 12 is a circular tube and the case where it is a flat tube. It is an external perspective view which shows one structural example of the heat exchanger of Embodiment 3 of this invention. It is an enlarged view of the main part including the hairpin part shown in FIG. It is external schematic diagram which shows one structural example of the heat exchanger of Embodiment 4 of this invention. FIG. 5 is a top perspective view showing a configuration example of the header mechanism shown in FIG. It is sectional drawing of the line segment AA shown in FIG. It is a schematic diagram for demonstrating the flow of a refrigerant about the heat exchanger shown in FIG.

Embodiment 1.
The configuration of the refrigeration cycle apparatus to which the heat exchanger of the first embodiment is applied will be described. FIG. 1 is a refrigerant circuit diagram showing a configuration example of a refrigeration cycle device including the heat exchanger according to the first embodiment of the present invention. The refrigeration cycle device 1 has a heat source side unit 2 and a load side unit 3. The heat source side unit 2 includes a compressor 4, a flow path switching device 5, a heat exchanger 6, a throttle device 7, a heat source side blower 10, and a control device 13. The load side unit 3 has a load side heat exchanger 11 and a load side blower 12. The compressor 4, the heat exchanger 6, the throttle device 7, and the load-side heat exchanger 11 are connected by a refrigerant pipe to form a refrigerant circuit 15 in which the refrigerant circulates.

The compressor 4 compresses and discharges the refrigerant circulating in the refrigerant circuit 15. The compressor 4 is, for example, a compressor such as a rotary compressor, a scroll compressor, a screw compressor, and a reciprocating compressor. The flow path switching device 5 is provided on the discharge side of the compressor 4. The flow path switching device 5 switches the flow of the refrigerant according to the operation modes of the heating operation and the cooling operation. Specifically, the flow path switching device 5 switches the flow path so as to connect the compressor 4 and the heat exchanger 6 during the cooling operation, and connects the compressor 4 and the load side heat exchanger 11 during the heating operation. Switch the flow path so as to. The flow path switching device 5 is, for example, a four-way valve.

The heat exchanger 6 functions as an evaporator during the heating operation and as a condenser during the cooling operation. When the heat exchanger 6 functions as an evaporator, in the heat exchanger 6, the low-temperature low-pressure refrigerant flowing out of the throttle device 7 and the air supplied from the heat source side blower 10 exchange heat, and the low-temperature low-pressure liquid refrigerant is exchanged. Alternatively, the two-phase refrigerant evaporates. On the other hand, when the heat exchanger 6 functions as a condenser, in the heat exchanger 6, the high temperature and high pressure refrigerant discharged from the compressor 4 and the air supplied from the heat source side blower 10 exchange heat, and the high temperature and high pressure The gas refrigerant condenses. The configuration of the heat exchanger 6 will be described in detail later.

The throttle device 7 expands the refrigerant flowing out of the heat exchanger 6 or the load side heat exchanger 11 to reduce the pressure. The throttle device 7 is, for example, an electric expansion valve capable of adjusting the flow rate of the refrigerant. The throttle device 7 is not limited to the electric expansion valve, and may be a mechanical expansion valve that employs a diaphragm in the pressure receiving portion, or a device such as a capillary tube.

The heat source side blower 10 is attached to the heat exchanger 6. The heat source side blower 10 supplies air to the heat exchanger 6 by rotating. The heat source side blower 10 is, for example, a fan such as a propeller fan and a turbo fan. The condensing capacity and evaporation capacity of the heat exchanger 6 are adjusted by the rotation speed of the heat source side blower 10.

The control device 13 has a memory (not shown) for storing a program and a CPU (Central Processing Unit) (not shown) for executing processing according to the program. The control device 13 is, for example, a microcomputer. The control device 13 is communicatively connected to the compressor 4, the flow path switching device 5, the throttle device 7, the heat source side blower 10, the load side blower 12, and various sensors not shown in the figure.

The control device 13 includes a compressor 4, a flow path switching device 5, and a throttle device 7, depending on an operation instruction from a user, measured values of various sensors (not shown in the figure), and required cooling capacity and heating capacity. Each device of the heat source side blower 10 and the load side blower 12 is controlled. Specifically, the control device 13 controls the drive frequency of the compressor 4 and the opening degree of the throttle device 7 according to the required cooling capacity and heating capacity. Further, the control device 13 controls the rotation speeds of the heat source side blower 10 and the load side blower 12 according to the required cooling capacity and heating capacity. The control device 13 controls switching of the flow path switching device 5 according to the operation mode.

The load-side heat exchanger 11 functions as a condenser during the heating operation and as an evaporator during the cooling operation. When the load side heat exchanger 11 functions as a condenser, the load side heat exchanger 11 exchanges heat between the high temperature and high pressure refrigerant discharged from the compressor 4 and the air supplied from the load side blower 12, and the temperature is high. High-pressure gas refrigerant condenses. On the other hand, when the load-side heat exchanger 11 functions as an evaporator, the load-side heat exchanger 11 exchanges heat between the low-temperature low-pressure refrigerant flowing out of the throttle device 7 and the air supplied from the load-side blower 12. , Low temperature and low pressure liquid refrigerant or two-phase refrigerant evaporates.

The load side heat exchanger 11 includes, for example, a fin and tube heat exchanger, a microchannel heat exchanger, a shell and tube heat exchanger, a heat pipe heat exchanger, a double tube heat exchanger and a plate. It is a heat exchanger such as a heat exchanger. In the first embodiment, the load side heat exchanger 11 is a heat exchanger that exchanges heat between air and a refrigerant. The condensing capacity and evaporation capacity of the load side heat exchanger 11 are adjusted by the rotation speed of the load side blower 12.

The load-side blower 12 is attached to the load-side heat exchanger 11. The load-side blower 12 rotates to supply air to the load-side heat exchanger 11. The load side blower 12 is, for example, a fan such as a propeller fan, a cross flow fan, a sirocco fan, and a turbo fan.

In the first embodiment, the case where the control device 13 is provided in the heat source side unit 2 will be described, but the installation location of the control device 13 is not limited to the heat source side unit 2. For example, the control device 13 may be provided in the load side unit 3. Further, although the case where the throttle device 7 is provided in the heat source side unit 2 will be described, the throttle device 7 may be provided in the load side unit 3.

FIG. 1 shows a configuration in which one load side unit 3 and one heat source side unit 2 are connected, but the number and connection configuration of the heat source side unit 2 and the load side unit 3 are shown in FIG. Not limited to the case. The refrigeration cycle device 1 may have a plurality of heat source side units 2 and a plurality of load side units 3. A plurality of heat source side units 2 and a plurality of load side units 3 may be connected in parallel or in series, or a plurality of load side units 3 may be connected in parallel or in series to one heat source side unit 2. Good.

Here, the flow of the refrigerant in the operation mode of the refrigeration cycle device 1 will be described.
[Cooling operation]
The flow of the refrigerant when the refrigeration cycle device 1 performs the cooling operation will be described with reference to FIG. In FIG. 1, the flow direction of the refrigerant in the refrigerant circuit 15 is indicated by an arrow. When the refrigerating cycle device 1 performs the cooling operation, the control device 13 switches the flow path of the flow path switching device 5 so that the refrigerant discharged from the compressor 4 flows into the heat exchanger 6. When the low-temperature and low-pressure refrigerant is compressed by the compressor 4, the high-temperature and high-pressure gas refrigerant is discharged from the compressor 4. The gas refrigerant discharged from the compressor 4 flows into the heat exchanger 6 via the flow path switching device 5. The refrigerant that has flowed into the heat exchanger 6 is condensed by exchanging heat with air in the heat exchanger 6, becomes a low-temperature and high-pressure liquid refrigerant, and flows out of the heat exchanger 6.

The liquid refrigerant flowing out of the heat exchanger 6 becomes a low-temperature low-pressure liquid refrigerant by the drawing device 7. The liquid refrigerant flows into the load side heat exchanger 11. The refrigerant that has flowed into the load-side heat exchanger 11 evaporates by exchanging heat with air in the load-side heat exchanger 11, becomes a low-temperature low-pressure gas refrigerant, and flows out of the load-side heat exchanger 11. In the load side heat exchanger 11, the refrigerant absorbs heat from the air in the air-conditioned space, so that the air in the air-conditioned space is cooled. The refrigerant flowing out of the load-side heat exchanger 11 is sucked into the compressor 4 via the flow path switching device 5. While the refrigerating cycle device 1 is performing the cooling operation, the refrigerant discharged from the compressor 4 flows through the heat exchanger 6, the drawing device 7, and the load side heat exchanger 11 in this order, and then is sucked into the compressor 4. The cycle up to is repeated.

[Heating operation]
Next, the flow of the refrigerant when the refrigeration cycle device 1 performs the heating operation will be described. FIG. 2 is a diagram showing a flow of refrigerant when the refrigeration cycle apparatus shown in FIG. 1 performs a heating operation. In FIG. 2, the flow direction of the refrigerant in the refrigerant circuit 15 is indicated by an arrow. When the refrigeration cycle device 1 performs the heating operation, the control device 13 switches the flow path of the flow path switching device 5 so that the refrigerant discharged from the compressor 4 flows into the load side heat exchanger 11.

When the low-temperature and low-pressure refrigerant is compressed by the compressor 4, the high-temperature and high-pressure gas refrigerant is discharged from the compressor 4. The high-temperature and high-pressure gas refrigerant discharged from the compressor 4 flows into the load-side heat exchanger 11 via the flow path switching device 5. The refrigerant flowing into the load-side heat exchanger 11 is condensed by exchanging heat with air in the load-side heat exchanger 11, becomes a high-temperature and high-pressure liquid refrigerant, and flows out from the load-side heat exchanger 11. In the load side heat exchanger 11, the air in the air-conditioned space is warmed by radiating heat from the refrigerant to the air in the air-conditioned space.

The high-temperature and high-pressure liquid refrigerant flowing out of the load-side heat exchanger 11 becomes a low-temperature and low-pressure liquid refrigerant by the drawing device 7. The liquid refrigerant flows into the heat exchanger 6. The refrigerant that has flowed into the heat exchanger 6 evaporates by exchanging heat with air in the heat exchanger 6, becomes a low-temperature low-pressure gas refrigerant, and flows out of the heat exchanger 6. The refrigerant flowing out of the heat exchanger 6 is sucked into the compressor 4 via the flow path switching device 5. While the refrigerating cycle device 1 is performing the heating operation, the refrigerant discharged from the compressor 4 flows through the load side heat exchanger 11, the drawing device 7, and the heat exchanger 6 in this order, and then is sucked into the compressor 4. The cycle until is repeated.

[Structure of heat exchanger 6]
Next, the configuration of the heat exchanger 6 shown in FIG. 1 will be described. FIG. 3 is an external perspective view showing a configuration example of the heat exchanger shown in FIG. FIG. 4 is a side view of the heat exchanger shown in FIG. As shown in FIG. 3, the heat exchanger 6 has a first heat exchange unit 21a, a second heat exchange unit 21b, a connecting member 40, a second header 50, and a first header 60. The arrow shown in FIG. 3 indicates the blowing direction, which is the flow direction of the air supplied from the heat source side blower 10. FIG. 3 shows that the first heat exchange unit 21a is arranged upwind and the second heat exchange unit 21b is arranged downwind.

The first heat exchange unit 21a has a plurality of first fins 22a, a plurality of first heat transfer tubes fixed to the plurality of first fins 22a, and a header tube 70a. The plurality of first heat transfer tubes have a first straight tube 23a and a first long tube 24a. The length of the first long pipe 24a in the Y-axis arrow direction is longer than that of the first straight pipe 23a. The header pipe 70a connects the ends of the first straight pipe 23a and the first long pipe 24a on one side (in the direction of the Y-axis arrow). Of the two ends of the first long pipe 24a, one end is connected to the header pipe 70a and the other end is directly connected to the first header 60. In the configuration example shown in FIG. 3, the first heat exchange unit 21a has eight sets of the first straight pipe 23a and the first long pipe 24a.

The second heat exchange unit 21b has a plurality of second fins 22b, a plurality of second heat transfer tubes fixed to the plurality of second fins 22b, and a header tube 70b. The plurality of second heat transfer tubes have a second straight tube 23b and a second long tube 24b. The length of the second long pipe 24b in the Y-axis arrow direction is longer than that of the second straight pipe 23b. The header pipe 70b connects the ends of the second straight pipe 23b and the second long pipe 24b on one side (in the direction of the Y-axis arrow). Of the two ends of the second long pipe 24b, one end is connected to the header pipe 70b and the other end is directly connected to the second header 50. In the configuration example shown in FIG. 3, the second heat exchange unit 21b has eight sets of the second straight pipe 23b and the second long pipe 24b.

The connecting member 40 has a joint 41a connected to the first straight pipe 23a, a joint 41b connected to the second straight pipe 23b, and a U-shaped pipe 42 connecting the joints 41a and 41b. Specifically, the joint 41a is connected to the end of the two ends of the first straight pipe 23a on the side opposite to the end connected to the header pipe 70a (in the opposite direction of the Y-axis arrow). There is. The joint 41b is connected to the end of the two ends of the second straight pipe 23b, which is opposite to the end connected to the header pipe 70b. The U-shaped tube 42 is a circular tube having a circular cross section. The connecting member 40 may have a configuration in which the joints 41a and 41b and the U-shaped pipe 42 are integrated.

The connecting member 40 may connect the first straight pipe 23a and the second straight pipe 23b in parallel with the horizontal plane (XY coordinate plane), but as shown in FIG. 3, along the plane inclined with respect to the horizontal plane. You may connect. That is, the connecting member 40 may connect the first straight pipe 23a and the second straight pipe 23b along the surface intersecting the vertical direction (Z-axis arrow direction).

In FIGS. 3 and 4, the first heat exchange section 21a has eight sets of the first straight pipe 23a and the first long pipe 24a, and the second heat exchange section 21b has eight sets of the second straight pipe 23b and the second straight pipe 23b. Although the configuration having the second long pipe 24b is shown, the number of pairs is not limited to eight. Further, in the first embodiment, the case where each heat transfer tube of the first straight tube 23a and the first long tube 24a and the second straight tube 23b and the second long tube 24b is a flat tube will be described, but the flat tube Not exclusively. The material of the first fin 22a, the second fin 22b and the flat tube is, for example, aluminum.

The second header 50 and the first header 60 serve as distributors for distributing and collecting the refrigerant. The second header 50 serves as a refrigerant inlet for the heat exchanger 6 when the heat exchanger 6 functions as a condenser, and serves as a refrigerant outlet for the heat exchanger 6 when the heat exchanger 6 functions as an evaporator. The second header 50 has a connection pipe 51 connected to the flow path switching device 5. The second header 50 is directly connected to the plurality of second long pipes 24b. The second header 50 distributes the gas refrigerant flowing from the discharge port of the compressor 4 through the flow path switching device 5 to the plurality of second long pipes 24b when the refrigeration cycle device 1 performs the cooling operation. The second header 50 merges the refrigerants flowing out from the plurality of second long pipes 24b when the refrigeration cycle device 1 performs the heating operation, and sucks the merged refrigerants into the compressor 4 via the flow path switching device 5. It leaks into the mouth. The material of the second header 50 is the same as that of the second long pipe 24b. The material of the second header 50 is, for example, aluminum.

The first header 60 serves as a refrigerant inlet of the heat exchanger 6 when the heat exchanger 6 functions as an evaporator, and serves as a refrigerant outlet of the heat exchanger 6 when the heat exchanger 6 functions as a condenser. The first header 60 has a connecting pipe 61 connected to the drawing device 7. The first header 60 is directly connected to the plurality of first long tubes 24a. When the refrigeration cycle device 1 performs the cooling operation, the first header 60 merges the refrigerants flowing out from the plurality of first long pipes 24a, and the merged refrigerant flows out to the throttle device 7. The first header 60 distributes the refrigerant flowing from the drawing device 7 to the plurality of first long pipes 24a when the refrigerating cycle device 1 performs the heating operation. The material of the first header 60 is the same as that of the first long pipe 24a. The material of the first header 60 is, for example, aluminum.

When the materials of the second header 50, the first header 60, the first long pipe 24a and the second long pipe 24b are all the same, the brazing process of the second header 50 and the plurality of second long pipes 24b and the first header The brazing process of 60 and the plurality of first long tubes 24a can be performed at one time.

FIG. 5 is a side perspective view showing a configuration example of the header tube shown in FIG. Since the header tubes 70a and 70b have the same configuration, the configuration of the header tube 70a will be described here. The header pipe 70a shown in FIG. 5 has a tubular structure provided with a space for adjusting the flow direction of the refrigerant. The shape of the header tube 70a is not limited to a tubular shape, and may be a rectangular parallelepiped shape.

The header pipe 70a is provided with a plurality of partition walls 71 for partitioning the space provided inside into a plurality of sections at equal intervals in the vertical direction (Z-axis arrow direction). The ends of the first straight pipe 23a and the first long pipe 24a are connected to each other in each of the plurality of compartments partitioned by the partition wall 71. With this configuration, in each set of the eight sets of the first straight pipe 23a and the first long pipe 24a, the refrigerant can flow between the first straight pipe 23a and the first long pipe 24a.

The material of the header pipe 70a is the same as that of the first straight pipe 23a and the first long pipe 24a. The material of the header pipe 70b is the same as that of the second straight pipe 23b and the second long pipe 24b. The material of the header tubes 70a and 70b is, for example, aluminum. When the materials of the header pipes 70a and 70b, the first straight pipes 23a and the first long pipe 24a, and the second straight pipes 23b and the second long pipe 24b are all the same, the header pipes 70a and 70b and their heat transfer pipes The brazing process can be performed at once.

Here, the flow path of the refrigerant in the heat exchanger 6 will be described. As shown in FIGS. 3 and 4, of the two ends of the first long pipe 24a, one end is connected to the first header 60 and the other end is the first straight through the header pipe 70a. It is connected to the tube 23a. The first straight pipe 23a is connected to the connecting member 40 on the side opposite to the header pipe 70a. The connecting member 40 is connected to the second straight pipe 23b on the opposite side of the first straight pipe 23a. Of the two ends of the second straight pipe 23b, one end is connected to the connecting member 40, and the other end is connected to the second long pipe 24b via the header pipe 70b. The second long pipe 24b is connected to the second header 50 on the opposite side of the header pipe 70b. With this configuration, the refrigerant flowing into the heat exchanger 6 reciprocates twice in the direction of the Y-axis arrow of the heat exchanger 6 and flows out from the heat exchanger 6.

FIG. 6 is a top view of the heat exchanger shown in FIG. In one direction (arrow in the Y-axis direction), the length from the connecting member between the first straight pipe 23a and the header pipe 70a to the connecting member between the first straight pipe 23a and the joint 41b is L1. Further, in one direction (arrow in the Y-axis direction), the length from the connecting member between the first long pipe 24a and the header pipe 70a to the connecting member between the first long pipe 24a and the first header 60 is L2. As shown in FIG. 6, the length L1 is shorter than the length L2. This relationship of length is the same for the second straight pipe 23b and the second long pipe 24b.

According to the above configuration, the connection position between the first straight pipe 23a and the joint 41a is closer to the plurality of first fins 22a than the connection position between the first long pipe 24a and the first header 60. Further, the connection position between the second straight pipe 23b and the joint 41b is closer to the plurality of second fins 22b than the connection position between the second long pipe 24b and the second header 50. As a result, as shown in FIG. 6, the U-shaped pipe 42 can be provided in the space between the joints 41a and 41b and the second header 50 and the first header 60.

Next, the flow of the refrigerant in the heat exchanger 6 will be described.
[Cooling operation]
The flow of the refrigerant in the heat exchanger 6 will be described with reference to FIG. 7 in the case where the refrigeration cycle device 1 performs the cooling operation. FIG. 7 is a diagram showing the flow of the refrigerant in the heat exchanger during the cooling operation. In FIG. 7, the first header 60 and the second header 50 are omitted from the figure. Further, in FIG. 7, the uppermost second straight pipe 23b and the second long pipe 24b are shown in the figure, and the other second straight pipe 23b and the second long pipe 24b are omitted in the figure. Further, in FIG. 7, the direction in which the refrigerant flows is indicated by a solid arrow.

The high-temperature and high-pressure gas refrigerant discharged from the compressor 4 flows into the second header 50 via the connection pipe 51 shown in FIG. The refrigerant flowing into the second header 50 is shunted into the plurality of second long pipes 24b. In FIG. 7, the refrigerant flowing into the uppermost second long pipe 24b is indicated by a solid arrow. The refrigerant that has flowed into the second long pipe 24b circulates in the direction of the Y-axis arrow and reaches the header pipe 70b. The refrigerant flows into the second straight pipe 23b via the header pipe 70b. The refrigerant flows through the second straight pipe 23b in the direction opposite to the Y-axis arrow and reaches the connecting member 40. The refrigerant flows into the first straight pipe 23a via the connecting member 40. The refrigerant flows through the first straight pipe 23a in the direction of the arrow on the Y axis and reaches the header pipe 70a. The refrigerant flows into the first long pipe 24a via the header pipe 70a. The refrigerant flows through the first long pipe 24a in the direction opposite to the Y-axis arrow and reaches the first header 60. Refrigerant flows into the first header 60 shown in FIG. 3 from the plurality of first long pipes 24a. The refrigerant merged in the first header 60 flows out from the heat exchanger 6 via the connecting pipe 61.

[Heating operation]
The flow of the refrigerant in the heat exchanger 6 will be described with reference to FIG. 8 in the case where the refrigeration cycle device 1 performs the heating operation. FIG. 8 is a diagram showing the flow of the refrigerant in the heat exchanger during the heating operation. In FIG. 8, similarly to FIG. 7, the first header 60 and the second header 50 are omitted from the drawings. Further, also in FIG. 8, the uppermost second straight pipe 23b and the second long pipe 24b are shown in the figure, and the other second straight pipe 23b and the second long pipe 24b are omitted in the figure. Further, in FIG. 8, the direction in which the refrigerant flows is indicated by a solid arrow.

The liquid refrigerant or gas-liquid two-phase refrigerant flowing out of the throttle device 7 flows into the first header 60 via the connection pipe 61 shown in FIG. The refrigerant flowing into the first header 60 is shunted into the plurality of first long pipes 24a. In FIG. 8, the refrigerant flowing into the first long pipe 24a at the uppermost stage is indicated by a solid arrow. The refrigerant that has flowed into the first long pipe 24a circulates in the direction of the Y-axis arrow and reaches the header pipe 70a. The refrigerant flows into the first straight pipe 23a via the header pipe 70a. The refrigerant flows through the first straight pipe 23a in the direction opposite to the Y-axis arrow and reaches the connecting member 40. The refrigerant flows into the second straight pipe 23b via the connecting member 40. The refrigerant flows through the second straight pipe 23b in the direction of the Y-axis arrow and reaches the header pipe 70b. The refrigerant flows into the second long pipe 24b via the header pipe 70b. The refrigerant flows through the second long pipe 24b in the direction opposite to the Y-axis arrow and reaches the second header 50. Refrigerant flows into the second header 50 shown in FIG. 3 from the plurality of second long pipes 24b. The refrigerant merged in the second header 50 flows out from the heat exchanger 6 via the connecting pipe 51.

Regardless of whether the refrigerating cycle device 1 is in the cooling operation or the heating operation, the refrigerant reciprocates the heat exchanger 6 twice in the Y-axis arrow direction. Therefore, in the heat exchanger 6, the refrigerant can sufficiently exchange heat with the outdoor air.

Here, the advantages when the first straight pipe 23a and the first long pipe 24a and the second straight pipe 23b and the second long pipe 24b are flat pipes will be described. FIG. 9 is a schematic view for explaining the difference between the case where the first heat transfer tube shown in FIG. 1 is a flat tube and the case where the first heat transfer tube is a circular tube. Here, the case where the two heat transfer tubes adjacent to each other in the vertical direction are the first straight tube 23a and the first long tube 24a will be described.

The cross-sectional area of the flat tube and the cross-sectional area of the circular tube shown in FIG. 9 are the same. Further, for comparison, in FIG. 9, the center positions of the cross sections of the first straight tube 23a of the flat tube and the first straight tube 23a of the circular tube are shown in the vertical direction (Z-axis arrow direction). Matching. Further, the center positions of the cross sections of the first long tube 24a of the flat tube and the first long tube 24a of the circular tube are aligned with each other in the vertical direction.

Generally, assuming that the air volume Q, the passing wind speed v, the shape coefficient C, and the passing area A, the ventilation resistance ΔP of the air passing between the two heat transfer tubes is expressed by the following equation. However, v = Q / A.

Assuming that the shape coefficient C is constant, the value that affects the equation (1) is the passing area A. As the vertical distance between the first straight pipe 23a and the first long pipe 24a, the distance in the case of a flat pipe is Hf, and the distance in the case of a circular pipe is Hc. It is clear from FIG. 9 that the distance Hf> the distance Hc. The length W of the first straight pipe 23a and the first long pipe 24a in the Y-axis arrow direction shall be the same value for both the flat pipe and the circular pipe. The passage area Af in the case of a flat tube is represented by Af = W × Hf. The passing area Ac in the case of a circular tube is represented by Ac = W × Hc. Since the distance Hf> the distance Hc, the passing area Af> the passing area Ac.

Let vf be the ventilation speed in the case of a flat pipe, and vc be the ventilation speed in the case of a circular pipe. The ventilation velocity vf in the case of a flat tube is expressed as vf = Q / Af. The ventilation velocity vc in the case of a circular pipe is expressed as vc = Q / Ac. Since the passing area Af> the passing area Ac, the ventilation speed vf <the ventilation speed vc. Assuming that the ventilation resistance in the case of a flat pipe is ΔPf and the ventilation resistance in the case of a circular pipe is ΔPc, the ventilation resistance ΔPf <ventilation resistance ΔPc is obtained from the magnitude relationship between the ventilation speed vf and vc and the equation (1). Therefore, the flat pipe has a smaller ventilation resistance than the circular pipe. When the heat transfer tube is a flat tube, the number of heat radiation fins can be increased until the ventilation resistance becomes the same as that of the circular tube. As a result, the heat transfer performance of the flat tube is improved as compared with that of the circular tube.

Further, the flat tube may have a configuration having a plurality of flow paths for dividing the refrigerant into a plurality of streams. FIG. 10 is a cross-sectional view showing a configuration example when the first heat transfer tube shown in FIG. 3 is a flat tube. FIG. 10 shows an example in the case where the first straight pipe 23a is a flat pipe. As shown in FIG. 10, the first straight pipe 23a has a plurality of flow paths pd1 to pd6 parallel to the flow direction of the refrigerant. Although the case where the number of flow paths is 6 will be described, the number of flow paths is not limited to 6.

In the first embodiment, the advantages of the connecting member 40 when the heat transfer tube is the flat tube shown in FIG. 10 will be described. FIG. 11 is a schematic top view of the connecting member shown in FIG. As shown in FIG. 10, when the flow direction of the air supplied to the first straight pipe 23a is opposite to the direction of the X-axis arrow, the heat exchange efficiency of the refrigerant flowing in the windward flow path pd6 is the highest and the leeward direction. It is considered that the heat exchange efficiency of the refrigerant flowing through the side flow path pd1 is the lowest. That is, among the refrigerants flowing through the plurality of flow paths pd1 to pd6, the temperature of the refrigerant flowing through the flow path pd6 is the lowest, and the temperature of the refrigerant flowing through the flow path pd1 is the highest.

On the other hand, in the first embodiment, even if there is a temperature variation between the refrigerants shunted in the plurality of flow paths pd1 to pd6, as shown in FIG. 11, the refrigerants shunted into the plurality of flow paths merge at the joint 41a. After that, it flows through the U-shaped tube 42 of one circular tube. Therefore, while the refrigerant flows through the U-shaped pipe 42, the temperature difference between the refrigerants is reduced and the temperature of the refrigerant becomes uniform.

In the heat exchanger 6 of the first embodiment, the connecting member 40 is closer to the ends of the plurality of first fins 22a and the ends of the plurality of second fins 22b than the first header 60 and the second header 50. It is located.

In the first embodiment, the first long pipe 24a is directly connected to the first header 60, and the second long pipe 24b is directly connected to the second header 50. Further, the length of the first straight pipe 23a is shorter than that of the first long pipe 24a, and the length of the second straight pipe 23b is shorter than that of the second long pipe 24b. The flow direction of the refrigerant is switched in the opposite direction to the space formed by the difference in length between the first straight pipe 23a and the first long pipe 24a and the difference in length between the second straight pipe 23b and the second long pipe 24b. The connecting member 40 can be provided. As a comparative example, the length of the first straight pipe 23a is made longer than that of the first long pipe 24a, the length of the second straight pipe 23b is made longer than that of the second long pipe 24b, and each pipe is penetrated through the distributor. It is conceivable to provide a configuration on the outside of the distributor to switch the flow direction of the refrigerant in the opposite direction. In the comparative example, the length of the first straight pipe 23a is longer than that of the first long pipe 24a by the length until it penetrates the distributor and goes out. Similar to the first straight pipe 23a, the length of the second straight pipe 23b is longer than that of the second long pipe 24b by the length until it penetrates the distributor and goes out. Further, since the configuration for switching the flow direction of the refrigerant in the opposite direction is provided on the outside of the distributor, the heat exchanger becomes larger in the direction of the Y-axis arrow shown in FIG. 3 by the amount of the switching configuration. On the other hand, in the first embodiment, the configuration for switching the flow direction of the refrigerant in the opposite direction is provided not on the outside of the distributor but on the side closer to the center of the heat exchanger 6 than the distributor. Therefore, not only the length of the refrigerant flow path in the heat exchanger 6 can be secured, but also the heat exchanger 6 can be prevented from becoming large in the direction of the Y-axis arrow shown in FIG.

Further, in the first embodiment, the length of the path can be freely changed depending on how many combinations of the first straight pipe 23a, the connecting member 40 and the second straight pipe 23b are provided in the vertical direction (Z-axis arrow direction). Therefore, the degree of freedom in path design is improved.

Embodiment 2.
The heat exchanger of the second embodiment has an improved heat exchange function as compared with the heat exchanger of the first embodiment. In the second embodiment, detailed description of the configuration similar to that of the first embodiment will be omitted.

The configuration of the heat exchanger of the second embodiment will be described. FIG. 12 is an external perspective view showing a configuration example of the heat exchanger according to the second embodiment of the present invention. Focusing on the two sets of the first straight pipe 23a and the first long pipe 24a adjacent to each other in the vertical direction (Z-axis arrow direction) in the first heat exchange unit 21a, the two first long pipes 24a are adjacent to each other in the vertical direction. Are arranged. Regarding the second heat exchange section 21b, as in the case of the first heat exchange section 21a, paying attention to the pair of the second straight pipe 23b and the second long pipe 24b that are vertically adjacent to each other, the two second long pipes 24b are arranged adjacent to each other in the vertical direction.

Therefore, the first straight pipe 23a whose length in the Y-axis direction is shorter than that of the first long pipe 24a is also arranged adjacent to the other first straight pipe 23a in the vertical direction. The second straight pipe 23b is also arranged adjacent to the other second straight pipe 23b in the vertical direction. Assuming that the height of the two second long pipes 24b sandwiching the two vertically adjacent connecting members 40 is H1, the height H1 is such that the two second long pipes 24b sandwich one connecting member 40 in between. Wider than the height when sandwiched. The height of the two first long pipes 24a sandwiching the two connecting members 40 adjacent to each other in the vertical direction is also the same as the height H1.

In the manufacturing process of the heat exchanger 6a, when the operator attaches the connecting member 40 to the first straight pipe 23a and the second straight pipe 23b, the height H1 is wide, so that it is easy to attach. Therefore, the work efficiency of attaching the connecting member is improved.

Next, the heat exchanger performance of the heat exchanger 6a will be described. Here, the case where the heat exchanger 6a functions as a condenser will be described. FIG. 13 is a diagram showing a state of the refrigerant when the heat exchanger shown in FIG. 12 functions as a condenser. The heat exchanger 6 shown in FIG. 3 is used as a comparative example. FIG. 14 is a schematic diagram for explaining the flow of the refrigerant in the heat exchanger of the comparative example. FIG. 15 is a schematic diagram for explaining the flow of the refrigerant in the heat exchanger shown in FIG.

The vertical axis of FIG. 13 indicates the temperature, and the horizontal axis indicates the position of the heat exchanger 6a. FIG. 13 shows the changes in the air temperature Tair and the refrigerant temperature Tre in the path from the refrigerant inlet Pin to the refrigerant outlet Pout in the heat exchanger 6a. The refrigerant inlet Pin corresponds to the second header 50, and the refrigerant outlet Pout corresponds to the first header 60. As shown in FIG. 13, when the refrigerant flows into the heat exchanger 6a from the refrigerant inlet Pin in the superheated gas state STg, it dissipates heat to the air and the temperature drops, resulting in a gas-liquid two-phase state STlg. Subsequently, the refrigerant is supercooled to a liquid state STl, and flows out from the refrigerant outlet Pout.

As shown in FIG. 14, in the heat exchanger 6 of the comparative example, the first straight pipe 23a and the first long pipe 24a are vertically adjacent to each other, and the second straight pipe 23b and the second long pipe 24b are also vertically adjacent to each other. It is a suitable configuration. Focusing on the second heat exchange section 21b, the high temperature refrigerant flows through the second long pipe 24b, and the medium temperature refrigerant flows through the second straight pipe 23b. Thermal interference occurs between the refrigerants due to the temperature difference of the refrigerants flowing through the heat transfer tubes of the second straight pipe 23b and the second long pipe 24b adjacent to each other in the vertical direction. Focusing on the first heat exchange section 21a, a medium-temperature refrigerant flows through the first straight pipe 23a, and a low-temperature refrigerant flows through the first long pipe 24a. Therefore, thermal interference occurs between the refrigerants due to the temperature difference of the refrigerants flowing in the heat transfer tubes of the first straight pipe 23a and the first long pipe 24a adjacent to each other in the vertical direction. Due to these thermal interferences, the heat exchanger performance deteriorates.

On the other hand, as shown in FIG. 15, in the heat exchanger 6a, the two first long pipes 24a are vertically adjacent to each other, and the two second long pipes 24b are vertically adjacent to each other. Focusing on the second heat exchange section 21b, the two second long tubes 24b through which the high-temperature refrigerant flows are adjacent to each other in the vertical direction. Focusing on the first heat exchange section 21a, the two first long tubes 24a through which the low-temperature refrigerant flows are adjacent to each other in the vertical direction. By vertically adjoining two heat transfer tubes through which refrigerants having relatively similar temperatures flow, heat exchange loss due to thermal interference is reduced. As a result, deterioration of heat exchanger performance is suppressed.

Similar to the configuration described with reference to FIG. 15, heat exchange also occurs when the two first straight pipes 23a are vertically adjacent to each other and the two second straight pipes 23b are vertically adjacent to each other. The effect of reducing the loss can be obtained.

Further, also in the second embodiment, the first straight pipe 23a and the first long pipe 24a and the second straight pipe 23b and the second long pipe 24b may be circular pipes, but have an advantage when they are flat pipes. explain. Here, the case of the first long pipe 24a will be described. FIG. 16 is a diagram illustrating a case where the first heat transfer tube shown in FIG. 12 is a circular tube and a case where the first heat transfer tube is a flat tube.

The distance Hb between the two first long pipes 24a adjacent to each other in the vertical direction is defined as the distance Hbf1 when the first long pipe 24a is a flat pipe. Further, the distance Hb when the first long pipe 24a is a circular pipe is defined as the distance Hbc1. As shown in FIG. 16, the distance Hbf1 is larger than the distance Hbc1. In the manufacturing process of the heat exchanger 6a, when processing a hole for attaching the first long tube 24a to the first header 60 in the first header 60, it is necessary to be careful not to connect the two holes when the distance Hb is short. There is. Further, when the first long tube 24a is brazed to the hole provided in the first header 60, if the distance Hb is too close, when the second long tube 24a is inserted into the hole and the brazing is applied. The first first long pipe 24a interferes with the work. Therefore, the flat pipe having a distance Hbf1 having a distance Hb larger than the distance Hbc1 has higher work efficiency than the circular pipe.

In the heat exchanger 6a of the second embodiment, the two first long tubes 24a are vertically adjacent to each other, and the two second long tubes 24b are vertically adjacent to each other. According to the second embodiment, when the refrigerant flows through the heat exchanger 6a, the heat interference in the vertical direction is suppressed, and the deterioration of the heat exchanger performance can be suppressed. Further, in the manufacturing process of the heat exchanger 6a, the work efficiency of attaching the connecting member 40 is improved.

Embodiment 3.
In the heat exchanger of the third embodiment, a hairpin structure is used instead of the header pipe as a means for switching the flow direction of the refrigerant in the opposite direction. In the third embodiment, detailed description of the configuration similar to that of the first embodiment will be omitted. Further, in the third embodiment, the heat exchanger 6 described in the first embodiment will be used as a base, but the heat exchanger described in the second embodiment may be applied to the third embodiment. ..

FIG. 17 is an external perspective view showing a configuration example of the heat exchanger according to the third embodiment of the present invention. As shown in FIG. 17, the first heat exchange portion 21a has a first hairpin portion 25a that connects the ends of the pair of first straight pipes 23a and the first long pipe 24a. The first heat exchange portion 21a is provided with the same number of first hairpin portions 25a as the number of pairs of the pair of first straight pipes 23a and the first long pipe 24a. The second heat exchange portion 21b has a second hairpin portion 25b that connects the ends of the pair of second straight pipes 23b and the second long pipe 24b. The second heat exchange portion 21b is provided with the same number of second hairpin portions 25b as the number of pairs of the pair of second straight pipes 23b and the second long pipe 24b.

FIG. 18 is an enlarged view of a main part including the hairpin part shown in FIG. As shown in FIG. 18, the second straight pipe 23b is connected to the second long pipe 24b via the second hairpin portion 25b on the opposite side of the second header 50 shown in FIG. The second hairpin portion 25b has a shape in which the letter U is laid down when viewed from the direction of the X-axis arrow. The linear heat transfer tube is bent in a U shape at the second hairpin portion 25b to form the second straight tube 23b, the second hairpin portion 25b, and the second long tube 24b, as shown in FIG. Since the configuration of the first hairpin portion 25a is the same as that of the second hairpin portion 25b, detailed description thereof will be omitted.

In the third embodiment, the first hairpin portion 25a and the second hairpin portion 25b have been described in the case where they are bent in the vertical direction (Z-axis arrow direction), but they may be bent in the horizontal direction.

The heat exchanger 6b of the third embodiment has a hairpin structure provided on the opposite side of the inlet and the outlet of the refrigerant to switch the flow direction of the refrigerant in the opposite direction. In the third embodiment, since the volume of the hairpin structure is smaller than the volume of the header tube, the amount of refrigerant required for the refrigeration cycle device 1 can be reduced. Further, if the heat transfer tube is bent into a U shape to form a hairpin structure, the header tube becomes unnecessary, the number of parts of the heat exchanger 6 can be reduced, and the manufacturing cost can be reduced.

Embodiment 4.
The heat exchanger of the fourth embodiment has a configuration in which the heat exchanger performance can be switched according to the state of the refrigerant. In the fourth embodiment, detailed description of the configuration similar to that of the first embodiment will be omitted. Further, in the fourth embodiment, the case where the heat exchanger includes the heat exchanger 6a described in the third embodiment will be described, but the heat exchanger described in the first and second embodiments will be described in the present embodiment. It may be applied to the fourth form.

The configuration of the heat exchanger according to the fourth embodiment will be described. FIG. 19 is a schematic external view showing a configuration example of the heat exchanger according to the fourth embodiment of the present invention. The heat exchanger 6c has a third header 82a, a fourth header 82b, and a header mechanism 80 in addition to the first heat exchange section 21a, the second heat exchange section 21b, the first header 60, and the second header 50. The first heat exchange unit 21a has a plurality of third heat transfer tubes 91a orthogonal to the plurality of first fins 22a, in addition to the first straight tube 23a and the first long tube 24a. The second heat exchange section 21b has a plurality of fourth heat transfer tubes 91b orthogonal to the plurality of second fins 22b, in addition to the second straight tube 23b and the second long tube 24b. FIG. 19 shows a case where six pairs of the third heat transfer tube 91a and the fourth heat transfer tube 91b are provided, but the number of sets is not limited to six.

For each heat transfer tube of the plurality of third heat transfer tubes 91a, one end of the two ends is connected to the header mechanism 80, and the other end is connected to the third header 82a. For each heat transfer tube of the plurality of fourth heat transfer tubes 91b, one end of the two ends is connected to the header mechanism 80, and the other end is connected to the fourth header 82b. A connection pipe 52 for connecting the fourth header 82b and the second header 50 is provided in the heat exchanger 6c.

FIG. 20 is a top perspective view showing a configuration example of the header mechanism shown in FIG. FIG. 21 is a cross-sectional view of the line segment AA shown in FIG. As shown in FIG. 20, the header mechanism 80 has a header pipe 81a and 81b and a connecting portion 83 connecting the header pipes 81a and 81b.

As shown in FIG. 21, the header tubes 81a and 81b are provided with a plurality of partition walls 92 that partition the space provided inside into a plurality of sections at equal intervals in the vertical direction (Z-axis arrow direction). In the header pipe 81a, the end portion of the third heat transfer pipe 91a is connected to each of the plurality of compartments partitioned by the partition wall 92. In the header pipe 81b, the end portion of the fourth heat transfer pipe 91b is connected to each of the plurality of compartments partitioned by the partition wall 92.

As shown in FIGS. 20 and 21, in the header tubes 81a and 81b, the sections adjacent to each other in the horizontal direction (X-axis arrow direction) are connected by the connecting portion 83 at the same position in the vertical direction. With this configuration, in each of the six sets of the third heat transfer tube 91a and the fourth heat transfer tube 91b, the refrigerant can flow between the third heat transfer tube 91a and the fourth heat transfer tube 91b.

The material of the header tube 81a is the same as that of the third heat transfer tube 91a. The material of the header tube 81b is the same as that of the fourth heat transfer tube 91b. The material of the header tubes 81a and 81b and the connecting portion 83 is, for example, aluminum. When the materials of the header mechanism 80, the third heat transfer tube 91a, and the fourth heat transfer tube 91b are all the same, the brazing process of the header mechanism 80 and these heat transfer tubes can be performed at once. Since the third header 82a has the same configuration as the first header 60 and the fourth header 82b has the same configuration as the second header 50, detailed description thereof will be omitted.

In the heat exchanger 6c shown in FIG. 19, the upper side in the direction perpendicular to the broken line DL (Z-axis arrow direction) is referred to as an upper heat exchange section, and the lower side below the broken line DL is referred to as a lower heat exchange section. The lower heat exchanger has the same configuration as the heat exchanger 6 described in the first embodiment. In the upper heat exchange section, the third heat transfer tube 91a is directly connected to the third header 82a, and the fourth heat transfer tube 91b is directly connected to the fourth header 82b. In the lower heat exchange section, the first long pipe 24a is directly connected to the first header 60 and the second long pipe 24b is directly connected to the second header 50, but the first straight pipe 23a and the second straight pipe 23a and the second straight. The pipes 23b are not connected to any of the headers, but are connected to each other via a connecting member 40. However, since the lengths of the first straight pipe 23a and the second straight pipe 23b are shorter than the lengths of the first long pipe 24a and the second long pipe 24b, the connecting member 40 is provided in the space created by the difference in length. ing. Therefore, the first header 60 and the third header 82a can be positioned at the same position with respect to the Y-axis arrow direction. Further, the second header 50 and the fourth header 82b can be set at the same position with respect to the Y-axis arrow direction. As a result, it is possible to prevent the heat exchanger 6c from becoming large.

Next, the flow of the refrigerant in the heat exchanger 6c will be described. The case where the refrigerant flowing into the heat exchanger 6c is a gas-liquid two-phase refrigerant having a small pressure loss and a low dryness will be described. FIG. 22 is a schematic diagram for explaining the flow of the refrigerant in the heat exchanger shown in FIG.

As shown in FIG. 22, when the refrigerant flowing through the refrigerant circuit 15 flows into the first header 60, the refrigerant is shunted into the two first long pipes 24a. The refrigerant that has flowed into the first long pipe 24a flows into the first straight pipe 23a via the first hairpin portion 25a. Subsequently, the refrigerant flows into the second straight pipe 23b via the first straight pipe 23a and the connecting member 40. The refrigerant flows from the second straight pipe 23b into the second long pipe 24b via the second hairpin portion 25b. Further, the refrigerant flowing out from the two second long pipes 24b flows into the fourth header 82b shown in FIG. 19 via the second header 50 and the connecting pipe 52.

In the upper heat exchange section, the refrigerant is shunted from the fourth header 82b to the six fourth heat transfer tubes 91b. The refrigerant that has flowed into the fourth heat transfer tube 91b flows into the third heat transfer tube 91a via the header mechanism 80. The refrigerant flowing through the six third heat transfer tubes 91a merges at the third header 82a and then flows out of the heat exchanger 6c.

In this way, the refrigerant flowing into the heat exchanger 6c is split into two at the lower heat exchange section, reciprocates twice in the direction of the Y-axis arrow, and then split into six at the upper heat exchanger, where the Y-axis arrow indicates. Make one round trip in the direction. In this case, the refrigerant flowing into the heat exchanger 6c circulates in the lower exchanger having a long distance in one path, so that the heat transfer performance when the heat exchanger 6c functions as a condenser can be improved. Further, when the heat exchanger 6c functions as an evaporator, the refrigerant flowing into the heat exchanger 6c has a high degree of wetness, so that pressure loss can be suppressed even if the path is long, and deterioration of the evaporator performance can be suppressed.

On the other hand, when the refrigerant flowing into the heat exchanger 6c is a gas-liquid two-phase refrigerant having a large pressure loss and a high dryness, the refrigerant flows through the heat transfer tube in the direction opposite to the path described with reference to FIG. .. That is, the refrigerant flowing into the heat exchanger 6c is divided into six at the upper heat exchange section, reciprocates once in the Y-axis arrow direction, then split into two at the lower heat exchange section, and is divided into two in the Y-axis arrow direction. Round trip. In this case, the refrigerant flowing into the heat exchanger 6c has a short distance in one path, but flows through the upper exchanger having a large number of distributions, so that the increase in pressure loss is suppressed.

The heat exchanger 6c of the fourth embodiment has a third heat transfer tube 91a and a fourth heat transfer tube 91b having a short path, a first straight tube 23a and a first long tube 24a having a long path, and a second straight tube 23b and a second. It is a combination of two long pipes 24b. According to the fourth embodiment, the path can be configured according to the state of the refrigerant flowing into the heat exchanger 6c. Further, since the horizontal positions of the distributor of the upper heat exchange unit and the distributor of the lower heat exchange unit are the same, it is possible to prevent the heat exchanger 6c from becoming large. Further, since the horizontal positions of the distributors of the upper heat exchange section and the lower heat exchange section are the same, the work efficiency is improved in the manufacturing process of the heat exchanger 6c.

1 Refrigeration cycle device, 2 Heat source side unit, 3 Load side unit, 4 Compressor, 5 Flow path switching device, 6, 6a to 6c heat exchanger, 7 Stretching device, 10 Heat source side blower, 11 Load side heat exchanger, 12 Load side blower, 13 Controller, 15 Coolant circuit, 21a 1st heat exchange section, 21b 2nd heat exchange section, 22a 1st fin, 22b 2nd fin, 23a 1st straight pipe, 23b 2nd straight pipe, 24a 1st long pipe, 24b 2nd long pipe, 25a 1st hairpin part, 25b 2nd hairpin part, 40 connecting member, 41a, 41b joint, 42 U-shaped pipe, 50 2nd header, 51, 52 connecting pipe, 60th 1 header, 61 connection pipe, 70a, 70b header pipe, 71 partition wall, 80 header mechanism, 81a, 81b header pipe, 82a third header, 82b fourth header, 83 connection part, 91a third heat transfer tube, 91b fourth transmission Heat pipe, 92 bulkheads.

Claims (6)

A first heat exchange unit including a plurality of first fins arranged along one direction and a plurality of first heat transfer tubes fixed to the plurality of first fins and having ends connected to each other on one side. ,
The first heat includes a plurality of second fins arranged along the one direction and a plurality of second heat transfer tubes fixed to the plurality of second fins and having ends connected to each other on one side. A second heat exchange unit arranged in the air blowing direction with respect to the exchange unit,
A connecting member that connects the ends of the first straight tube of the plurality of first heat transfer tubes and the second straight tube of the plurality of second heat transfer tubes on the other side.
Among the plurality of first heat transfer tubes, a first header connected to the other end of the first long tube having a length in one direction longer than that of the first straight tube.
Of the plurality of second heat transfer tubes, a second header connected to the other end of the second long tube having a length in one direction longer than that of the second straight tube, and
Have,
The connecting member is located closer to the ends of the plurality of first fins and the ends of the plurality of second fins than the first header and the second header.
Heat exchanger. In the first heat exchange section, the two first long tubes are arranged next to each other in the vertical direction in the one direction.
In the second heat exchange section, the two second long tubes are arranged next to each other in the vertical direction.
The heat exchanger according to claim 1. A third heat transfer tube provided in the first heat exchange section and fixed to the plurality of first fins, and
A fourth heat transfer tube provided in the second heat exchange section and fixed to the plurality of second fins, and
A header mechanism that connects the ends of the third heat transfer tube and the fourth heat transfer tube on one side, and
A third header connected to the other end of the third heat transfer tube,
A fourth header connected to the other end of the fourth heat transfer tube,
A connection pipe connecting the second header and the fourth header,
The heat exchanger according to claim 1 or 2, further comprising. A first hairpin portion that connects the ends of the first straight pipe and the first long pipe that are adjacent to each other in the vertical direction in one direction on one side thereof.
Further having a second hairpin portion for connecting the ends of the second straight pipe and the second long pipe adjacent to each other in the vertical direction on one side thereof.
The connecting member connects the ends of the first straight pipe and the second straight pipe to each other on the other side along a surface intersecting the vertical direction.
The heat exchanger according to any one of claims 1 to 3. Each of the plurality of first heat transfer tubes and the plurality of second heat transfer tubes is a flat tube having a plurality of flow paths parallel to the flow direction of the refrigerant.
The heat exchanger according to any one of claims 1 to 4, wherein the connecting member has a pipe having a circular cross section. The heat exchanger according to any one of claims 1 to 5.
A compressor that compresses and discharges the refrigerant,
A throttle device that expands the refrigerant and
A load-side heat exchanger in which the refrigerant exchanges heat with the air in the air-conditioned space.
Refrigeration cycle equipment with.

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