JP2017141999A - Header distributor, outdoor machine mounted with header distributor, and air conditioner - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a header distributor with a simple structure configured to distribute gas-liquid two-phase refrigerant to a plurality of pipes.SOLUTION: A header distributor includes a liquid header 1 including a refrigerant flow passage in which gas-liquid two-phase refrigerant flows, and an inlet part insertion flat pipe 2 configured to return refrigerant flowing inside the liquid header 1 to the liquid header 1. The inlet part insertion flat tube 2 is inserted into the liquid header 1. By the inserted inlet part insertion flat pipe 2, pressure of the refrigerant flow passage inside the liquid header 1 is partially reduced to facilitate occurrence of a circulation flow.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a header distributor that distributes refrigerant to an evaporative heat exchanger, an outdoor unit on which the evaporative heat exchanger and the header distributor are mounted, and an air conditioner.

  In the refrigeration cycle, when the refrigerant liquid condensed in the condenser is depressurized by the expansion valve, it becomes a refrigerant in a gas-liquid two-phase state in which refrigerant vapor and refrigerant liquid are mixed and flows into the evaporative heat exchanger. When the refrigerant flows into the evaporative heat exchanger in a gas-liquid two-phase state, the energy efficiency of the air conditioner may be reduced due to deterioration of distribution characteristics to the heat exchanger.

  In order to improve the distribution characteristics, the header distributor may be arranged in the evaporative heat exchanger. The header distributor is a device that includes a plurality of branched branch pipes and distributes the refrigerant through the branch pipes.

  However, since the distribution of the gas-liquid two-phase refrigerant in the header is greatly affected by the mass velocity of the refrigerant, the amount to be distributed may be greatly different. For example, a large amount of refrigerant is distributed to the upper part of the header when operating at a high output, and a large amount of refrigerant is distributed to the lower part of the header when operating at a low output.

  As a method for solving such a problem, there is a method in which a path that bypasses the upper and lower portions of the header is created to cause a circulation flow (for example, Patent Document 1).

International Publication No. 2007/094422

  In Patent Document 1, an orifice, an ejector mechanism, and the like are provided at a lower merging portion in order to cause a circulating flow by connecting an upper portion and a lower portion of a header. However, when these are provided, the header structure becomes complicated, which may increase the manufacturing effort. Moreover, there is a risk of causing a significant increase in cost.

  The present invention has been made to solve the above-described problems, and can provide a circulation flow with a simple header structure to distribute the refrigerant substantially evenly without providing special parts such as an orifice and an ejector. An object of the present invention is to provide a header distributor and an air conditioner equipped with the header distributor.

  The header distributor according to the present invention includes a liquid header, a plurality of heat exchanger connecting pipes, a bypass pipe, and a flat pipe. The liquid header has a refrigerant flow path inside, and the refrigerant flows from one end to the other end. The plurality of heat exchanger connecting pipes are connected to the liquid header between one end and the other end, and the refrigerant is distributed from the liquid header. The bypass pipe is connected to the liquid header on the other end side from the position where the plurality of heat exchanger connecting pipes are connected. One of the inlet-inserted flat tubes is connected to the bypass pipe outside the liquid header, and the other is inserted into the liquid header at the inlet that is one end side of the position where the plurality of heat exchanger connecting pipes are connected. Then, the refrigerant flows from the bypass pipe to the liquid header. In the liquid header, the cross-sectional area of the refrigerant flow passage in the portion where the flat tube inserted into the inlet portion is inserted is smaller than the cross-sectional area of the refrigerant flow passage on one end side and the other end side of this portion.

  According to the present invention, since the cross-sectional area of the refrigerant flow path in the part where the flat tube inserted into the inlet section is inserted is smaller than the cross-sectional area of the refrigerant flow path in the part where the bypass pipe is connected, Circulation flow is likely to occur. Therefore, the refrigerant can be distributed substantially evenly by a simple header structure without using special parts such as an orifice and an ejector.

The schematic diagram which shows the header distributor which concerns on Embodiment 1 of this invention. Schematic of the inlet part insertion flat tube used for a header distributor. Sectional drawing of the flow-path obstruction | occlusion part comprised by the inlet_port | entrance part insertion flat tube. Sectional drawing of the flow-path obstruction | occlusion part comprised by the inlet_port | entrance insertion flat tube which concerns on the modification of this invention. FIG. 3 is a schematic diagram of a circular tube-flat tube conversion joint used in the header distributor according to the first embodiment. Sectional drawing and top view of the circular pipe-flat tube conversion joint used for the header divider | distributor which concerns on Embodiment 1. FIG. Sectional drawing and top view of the circular tube-flat tube conversion joint which concern on the modification of this invention. The schematic of bypass piping used for the present invention. The schematic of the bypass header used for this invention. The header distributor which concerns on Embodiment 2 of this invention. The header divider | distributor which concerns on Embodiment 3 of this invention. The header distributor which concerns on Embodiment 4 of this invention. The outdoor unit which concerns on Embodiment 5 of this invention. The outdoor unit which concerns on the modification of this invention. The air conditioning apparatus which concerns on Embodiment 6 of this invention. The air conditioning apparatus which concerns on Embodiment 7 of this invention.

  Hereinafter, embodiments of a header distributor disclosed in the present application will be described in detail with reference to the accompanying drawings. The following embodiments are merely examples, and the present invention is not limited to these embodiments.

Embodiment 1 FIG.
FIG. 1 shows a header distributor according to the first embodiment. The header distributor includes a liquid header 1, an inlet insertion flat tube 2, a heat exchanger connection tube 3, a bypass pipe 4a, and a circular tube-flat tube conversion joint 5a.

  The refrigerant that has been condensed in the condenser and depressurized by the expansion valve into a gas-liquid two-phase state in which refrigerant vapor and refrigerant liquid are mixed flows from one end of the liquid header 1 into the liquid header 1. In the example shown in FIG. 1, the liquid flows into the liquid header 1 from the lower part (inlet part) of the liquid header 1 positioned below in the gravitational direction from above to below. The liquid header 1 has a circular tube shape, and the liquid header 1 has a refrigerant flow path through which a refrigerant flows.

  The refrigerant flowing in from the lower part of the liquid header 1 flows toward the other end of the liquid header 1. In the example shown in FIG. 1, the coolant is caused to flow toward the upper portion of the liquid header 1 positioned above. That is, the refrigerant flows in the direction opposite to the direction of gravity.

  Between one end and the other end of the liquid header 1, a plurality of heat exchanger connection pipes 3 connected to the heat exchanger are arranged side by side. The refrigerant flowing from the lower part of the liquid header 1 is distributed to the heat exchanger through the plurality of heat exchanger connecting pipes 3.

  A bypass pipe 4 a is connected near the upper portion of the liquid header 1. In the bypass pipe 4a, the coolant that has flowed toward the top of the liquid header 1 is flowed.

  One of the bypass pipes 4a is connected to the vicinity of the upper portion of the liquid header 1, while the other is connected to the inlet insertion flat tube 2 via a circular tube-flat tube conversion joint 5a described later. One of the inlet-inserted flat tubes 2 is connected to the bypass pipe 4 a via a circular tube-flat tube conversion joint 5 a, while the other is inserted into the liquid header 1. In the inlet-inserted flat tube 2, the refrigerant flowing through the bypass pipe 4 a flows to the liquid header 1.

  The liquid header 1 is inserted into the liquid header 1 so as to abut against the inner wall of the liquid header 1 as shown in FIG. A space formed between the inner wall of the liquid header 1 and the surface of the flat tube 2 inserted into the inlet portion becomes a refrigerant flow path. Therefore, in the liquid header 1, the horizontal distance is reduced in the vicinity of the outlet end of the inlet-inserted flat tube 2, and an area reduced portion A having a reduced cross-sectional area is formed. The liquid header 1 has a tubular shape, and a lower side into which the refrigerant flows is throttled by a flat tube 2 to form an area reduction portion A. Above the area reduction part A, a space in which a large number of thin tubes are connected is formed. The pressure of the refrigerant in the space is approximately the same as the pressure of the refrigerant in the vicinity of the other end of the liquid header 1, but is higher than the pressure of the refrigerant in the area reduction portion A. With such a configuration, a venturi effect is generated in the vicinity of the outlet end portion of the inlet insertion flat tube 2, and the refrigerant flowing from the lower portion flows to the other end of the liquid header 1. Further, the horizontal cross-sectional area of the bypass pipe 4a is smaller than the horizontal cross-sectional area of the liquid header 1, and the flow of the refrigerant due to the venturi effect is promoted.

  The liquid header 1 is tubular, and the flat tube 2 is inserted in a direction that intersects the direction in which the pipe that is the liquid header 1 extends. Specifically, the flat tube 2 is inserted from the insertion side to the opposite inner wall surface beyond the center of the tube of the liquid header 1. With such a configuration, an area reduction portion A in which the cross-sectional area of the liquid header 1 is reduced is formed in the vicinity of the insertion portion of the flat tube 2. Refrigerant is supplied from below the area reducing section A, rises through the flow path having the cross-sectional area of the pipe inner diameter of the liquid header 1, passes through the narrow flow path narrowed by the area reducing section A, and then pipes again. The flow passage having a cross-sectional area with an enlarged inner diameter is raised and distributed to the heat exchanger connecting pipe 3. In the example of FIGS. 1 to 4, the flat and wide two flat surfaces of the flat tube 2 are arranged to be one end side and the other end side of the liquid header 1, respectively. You may arrange | position so that it may become the one end side and other end side.

  The distance between the inlet end portion of the bypass pipe 4a into which the refrigerant flows in the vicinity of the other end of the liquid header 1 and the inlet end portion facing portion of the liquid header 1 facing the inlet end portion is determined as follows. Therefore, the distance between the outlet end portion of the flat tube 2 into which the refrigerant flows out and the outlet end portion of the liquid header 1 facing the outlet end portion is larger than the distance. In other words, the horizontal distance in the liquid header 1 near the inlet end of the bypass pipe 4a is larger than the horizontal distance in the liquid header 1 near the outlet end of the inlet insertion flat tube 2. With this configuration, compared to the case where the inlet insertion flat tube 2 is not inserted, the cross-sectional area of the refrigerant flow path in the area reduction portion A in the vicinity of the tip of the inserted inlet insertion flat tube 2 (see FIG. 3). (Hatched area) becomes smaller. That is, the refrigerant flow path area 8 is reduced. Therefore, in the liquid header 1, the difference in static pressure between the area reducing portion A in the vicinity of the tip of the inserted inlet flat tube 2 and the bypass suction portion B in the vicinity of the upper portion of the liquid header 1 to which the bypass pipe 4a is connected is large. Become. In order to obtain a good static pressure difference, for example, the cross-sectional area of the flow path in the area reduction part A is 30% or less with respect to the cross-sectional area of the flow path on one end side and the other end side of the inlet-inserted flat tube 2. It is desirable to make it smaller.

  In the header distributor, the refrigerant flows into the liquid header 1 in the state of a gas-liquid two-phase refrigerant, and passes through the flow path area reducing portion A formed by the inlet portion insertion flat tube 2. At this time, the refrigerant velocity v1 passing through the flow path area reducing portion A increases, and the static pressure p1 of the flow path area reducing portion A decreases accordingly. The refrigerant that has passed through the flow passage area reducing portion A flows into the heat exchanger connecting pipe 3 in a state where the gas and liquid are well mixed in the flow passage area reducing portion A, and is distributed substantially evenly.

  In the bypass suction portion B, the horizontal sectional area is sufficiently large as compared with the area reduction portion A. Therefore, the static pressure p2 of the bypass suction part B becomes larger than p1. The difference in static pressure at this time becomes the driving force that causes the circulation flow. Due to the difference in static pressure, the refrigerant that has reached the vicinity of the upper portion of the header passes through the bypass pipe 4a, passes through the inlet portion, passes through the flat tube 2, and merges with the main stream at the inlet area reduction portion A. In the header distributor according to the first embodiment, not all of the refrigerant accelerated by the area reduction unit A is distributed to the heat exchanger connecting pipe 3, and a part of the accelerated refrigerant is bypassed by suction at the upper part of the header. It is configured to reach part B. Therefore, it becomes easy to generate | occur | produce a circulating flow, and it can further promote uniform distribution.

  The refrigerant in the state of the gas-liquid two-phase refrigerant is stably and substantially uniformly supplied to the plurality of heat exchanger connecting pipes 3 by causing the circulation flow as described above. Therefore, the performance of the heat exchanger can be extracted without waste.

  In the example of FIG. 3, the flat tube 2 is inserted so as to abut against the inner wall of the liquid header 1, but the present invention is not limited to this example. For example, when the refrigerant flow rate at the inlet is large, the insertion length of the flat tube 2 inserted into the inlet may be shortened according to the refrigerant flow rate. In the experiments by the authors regarding the insertion length of the flat tube 2 inserted into the inlet, it has been found that when the insertion length is determined so as to block the refrigerant flow path area 8 by at least 1/2 or more, a circulation flow is generated. Yes. Further, for example, when the flow rate of the refrigerant flowing through the liquid header 1 is small, a circulation flow is difficult to occur. Therefore, as shown in FIG. 4, a part of the thickness of the liquid header 1 is shaved and the inside of the initial inner wall of the liquid header 1 The flat tube 2 may be inserted so as to reach the inlet. For example, in such a configuration, the cross-sectional area of the flow path in the area reduction portion A is reduced to 20% or less with respect to the cross-sectional area of the flow path on the one end side and the other end side of the inlet portion insertion flat tube 2. Is also possible. With this configuration, the refrigerant flow path area 8 is further reduced, the static pressure difference between the area reduction part A and the bypass suction part B is further increased, and a circulation flow is easily generated. Moreover, the area reduction part A can also be narrowed by rounding the corner | angular part of the front-end | tip of the inlet tube insertion flat tube 2, or making the front-end | tip shape which draws a circular arc according to the inner wall of the liquid header 1. Similar effects can be obtained. Moreover, the structure which deform | transforms so that the liquid header 1 may protrude toward the flat tube 2 may be sufficient in order to make the refrigerant | coolant flow path area between the liquid header 1 and the flat tube 2 small.

  In FIG. 1, the liquid header 1 is arranged so that the refrigerant in a gas-liquid two-phase refrigerant state is distributed to the plurality of heat exchanger connecting pipes 3 in the vertical direction perpendicular to the gravity direction. The present invention is not limited to this example. For example, a modified example in which gravity is applied in the paper surface direction of FIG. In the case of this modification, since there is no head difference in the liquid refrigerant flowing in the liquid header 1, a circulation flow is easily generated accordingly. Here, the head difference is the first value that replaces the energy of water at a certain point with the height of the water column and the second value that replaces the energy of water at another point with the height of the water column. Say the difference.

  The bypass pipe 4a and the inlet insertion flat tube 2 are connected via a circular tube-flat tube conversion joint 5a. The circular tube-flat tube conversion joint 5a is a relay part as shown in FIGS. As shown in FIG. 5, in order to connect the circular pipe bypass pipe 4a having a different outer shape and the flat tubular inlet-inserted flat pipe 2, the circular pipe-flat pipe conversion joint 5a has a circular shape as shown in FIG. A tube insertion hole 6a and a flat tube insertion hole 7 are provided.

  In the example shown in FIG. 6, the circular tube insertion hole 6a and the flat tube insertion hole 7 are in contact with each other, but the present invention is not limited to this example. For example, as shown in FIG. 7, the circular tube-flat tube joint 5a may further include a circular tube insertion hole 6b having a small diameter. By further providing the circular tube insertion hole 6b, workability during brazing is improved. Further, by further providing the circular tube insertion hole 6b, the flow path in the circular tube-flat tube joint 5a is narrowed, and it is possible to prevent the refrigerant from flowing back to the bypass pipe 4a. Therefore, even when the refrigerant flow rate is small, a circulating flow is easily generated.

  The bypass pipe 4a is a component that guides the refrigerant that has passed through the bypass suction part B from the flow path area reduction part A and flows to the outside of the liquid header 1 to the flow path area reduction part A again. As shown in FIG. 8, the bypass pipe 4 a is configured using a single deformed pipe. One pipe is preferably a thin tube such as a capillary tube that can be easily deformed. Here, the thin tube means a thin tube having a comparatively small cross-sectional area as compared with general piping used in the technical field of the header distributor.

  In FIG. 8, although the bypass piping 4a using one piping is illustrated, this invention is not limited to the example shown in FIG. For example, as shown in FIG. 9, it may be a header distributor configured using two bypass pipes 4a and 4b and a bypass header 10 connecting the two bypass pipes 4a and 4b.

  For example, a circular pipe or a flat pipe can be used as the heat exchanger connecting pipe 3 and the bypass pipe 4 a inserted into the liquid header 1.

Embodiment 2. FIG.
In Embodiment 1, the header divider | distributor comprised using the bypass header 10 which connects two bypass piping 4a, 4b and the two bypass piping 4a, 4b was shown as one modification. On the other hand, the second embodiment shows a header distributor using a thin tube instead of the bypass header 10.

  FIG. 10 shows an example in which a capillary tube 11 is used as a thin tube. As shown in FIG. 10, the bypass pipe 4a includes a portion extending in the horizontal direction and a portion extending in the vertical direction, and the bypass pipe 4b includes a portion extending in the horizontal direction.

  Compared with the case where the bypass header 10 is provided, the effect of suppressing the reverse flow phenomenon of the refrigerant from the inlet insertion flat tube 2 to the bypass pipe 4b is increased by providing the narrow capillary tube 11. Therefore, compared with the case where the bypass header 10 is provided, there is a higher possibility that a circulation flow can be generated even when the refrigerant flow rate is smaller, and the range of the refrigerant flow rate that can be used in the header distributor is increased.

  When the capillary tube 11 connecting the bypass pipe 4a and the bypass pipe 4b is configured to generate a flow resistance, a liquid pool can be formed in a portion extending in the vertical direction of the bypass pipe 4a. Specifically, a liquid pool can be created in the region C shown in FIG. As a result, the flow rate of the circulating flow passing through the two bypass pipes 4a and 4b is stabilized. Therefore, the pulsation phenomenon of the refrigerant flowing into the plurality of heat exchange connection tubes 3 can be reduced, and the refrigerant can be supplied to the plurality of heat exchange connection tubes 3 more stably. You may make it comprise at least one part of piping which connects the bypass piping 4 and the inlet insertion flat tube 2 with a capillary tube.

Embodiment 3 FIG.
In the first and second embodiments, the inlet insertion flat tube 2 is used as a path for the refrigerant to return to the liquid header 1. On the other hand, in the third embodiment, as shown in FIG. 11, a bypass branch pipe 12 is further provided near the root D of the inlet insertion flat pipe 2. In the third embodiment, not only the inlet insertion flat tube 2 but also the bypass branch tube 12 is connected to the liquid header 1, and the refrigerant circulation flow is not only from the inlet insertion flat tube 2 but also from the bypass branch tube 12. The configuration can return to 1.

  The root vicinity D of the inlet insertion flat tube 2 is close to the flow path area reducing portion A in the gravity direction but far from the flow path area reducing portion A in the horizontal direction. That is, a portion where the refrigerant flows from the bypass branch pipe 12 to the inside of the liquid header 1 (near the root D) and a portion where the refrigerant flows from the inlet insertion flat tube 2 to the inside of the liquid header 1 (channel area reducing portion A) Is closer in the direction of gravity than in the horizontal direction. In other words, the branch pipe length, which is the length of the portion where the bypass branch pipe 12 is inserted into the liquid header 1, is the flatness, which is the length of the portion where the inlet insertion flat tube 2 is inserted into the liquid header 1. The pipe length is also short, the distance between the bypass branch pipe 12 and the inlet insertion flat tube 2 is smaller than the difference between the branch pipe length and the flat tube length, and the portion where the refrigerant flows from the bypass branch pipe 12 into the liquid header 1 Is located on the other end side of the liquid header 1 with respect to the portion inserted into the liquid header 1 of the inlet tube insertion flat tube 2. Further, the positional relationship connecting the root vicinity D and the flow path area reducing portion A is not parallel to the flow path direction in which the refrigerant flows. Therefore, the vicinity of the root D is a region where the pressure is low as compared with the region connected in the gravity direction (channel direction) from the channel area reducing unit A and the channel area reducing unit A. By arranging the bypass branch pipe 12 serving as a return path of the circulating flow near the root D of such a low pressure, it becomes easier to generate the circulating flow.

  In FIG. 11, the liquid header 1 provided with the bypass header 10 and the bypass branch pipe 12 is shown as an example. However, the present invention is not limited to this example. Instead of the bypass header 10 and the bypass branch pipe 12, a thin tube such as a capillary tube may be arranged, the thin tube may be branched, and one of the branched thin tubes may be connected to the liquid header 1 as the bypass branch tube 12.

Embodiment 4 FIG.
In the third embodiment, the bypass branch pipe 12 is arranged near the root D of the inlet insertion flat tube 2 in order to make it easier to generate a circulation flow. On the other hand, in Embodiment 4, instead of the bypass branch pipe 12, an inlet insertion pipe hole 13 is provided near the root D of the inlet insertion flat pipe 2.

  FIG. 12 shows a header distributor according to the fourth embodiment. In the vicinity D of the root of the liquid header 1, an inlet insertion tube hole 13 for returning the circulating flow is provided. The tube hole 13 is provided on the other end side of the liquid header 1. The inlet insertion tube hole 13 is provided at a position in the horizontal direction away from the portion where the refrigerant flows from the inlet portion insertion flat tube 2 into the liquid header 1.

  Since the refrigerant flow path is partially and rapidly reduced by the inlet insertion flat tube 2, the refrigerant that has passed through the flow channel area reducing portion A after the inlet insertion flat tube 2 starts to expand rapidly. However, the pressure in the root portion D is lower than the pressure in the flow path area reducing portion A immediately after the inlet insertion flat tube 2. Therefore, by providing the tube hole 13 in the portion of the inlet insertion flat tube 2 connected to the root portion D, the circulation flow can easily flow, and the refrigerant can be stably and substantially uniformly supplied to the plurality of heat exchange connection tubes 3. it can.

  In the fourth embodiment, the refrigerant is allowed to flow in the flow passage area reducing portion A which is the tip of the tube hole 13 and the flat tube 2. However, it may be configured to flow only from the tube hole 13. The tube hole 13 may be disposed in the vicinity of the flow path area reducing portion A. In addition, since it is sufficient if there is a portion in which the cross-sectional area of the flow path is narrowed by the flat tube 2, the flow path area reducing portion A reaches the inner wall of the liquid header 1, A small-diameter hole penetrating from one end side to the other end side may be formed in the middle. In that case, the through hole becomes the flow channel area reduction portion A that narrows the cross-sectional area of the flow channel, and the refrigerant flows out from the inside of the flat tube 2 formed by the through hole, so that it also becomes the tube hole 13. The shape of the through hole is not limited to a round shape, and may be a slit shape.

Embodiment 5. FIG.
FIG. 13 shows a refrigerant circuit of the outdoor unit 100 on which the header distributor according to Embodiments 1 to 4 is mounted. In the outdoor unit 100, the outdoor heat exchanger 14, the plurality of gas side heat exchange connecting pipes 15, and the gas header 16 are connected in order downstream of the header distributor according to the first to fourth embodiments. The outdoor heat exchanger 14 is a device that performs heat exchange with a gas body using a liquid medium. For example, a fin tube type heat exchanger or the like can be used. The header distributor according to the first to fourth embodiments supplies the refrigerant in the gas-liquid two-phase state to the plurality of heat exchange connecting pipes 3 approximately equally.

  The refrigerant in the gas-liquid two-phase state distributed by the header distributor passes through the plurality of heat exchange connecting pipes 3 and exchanges heat with an ambient medium such as air or water in the outdoor heat exchanger 14. The heat exchanged refrigerant becomes gas and passes through the plurality of gas-side heat exchange coupling tubes 15. The gas that has passed through the plurality of gas-side heat exchange connection pipes 15 merges at the gas header 16 and flows out of the outdoor unit 100.

  In the example shown in FIG. 13, gas flows out from the lower part of the gas header 16. However, when the outflow part of the outdoor unit 100 through which gas flows out is installed in the lower part of the gas header 16, the heat exchange connecting pipe 3 located below is in a gas-liquid two-phase compared to the heat exchange connecting pipe 3 located above. The path length from the refrigerant inlet in the state to the outlet of the refrigerant turned into gas becomes short. Therefore, it is difficult for the refrigerant to flow up to the upper part of the liquid header 1, and there is a possibility that the circulating flow is less likely to occur. Therefore, as shown in FIG. 14, the gas may flow out from the upper part of the gas header 16. When the outdoor unit outflow part is installed at the upper part of the gas header 16, the difference between the path length passing through the lower heat exchange coupling pipe 3 and the path length passing through the upper heat exchange coupling pipe 3 is reduced. It becomes easy for the refrigerant to flow up to the top of the header 1. Further, a circulation flow is easily generated, and the refrigerant can be distributed to the heat exchange connecting pipe 3 stably and substantially uniformly.

Embodiment 6 FIG.
FIG. 15 shows a refrigerant circuit of an air conditioner equipped with the outdoor unit 100 according to the fifth embodiment. The air conditioner includes a compressor 17, an indoor unit 200, a discharge pipe 20 that connects the compressor 17 and the indoor unit 200, an expansion valve 18, an indoor unit outlet pipe 21 that connects the expansion valve 18 and the indoor unit 200, and an outdoor unit. And a suction pipe 19 for connecting the outdoor unit 100 and the compressor 17 to each other. In addition, in FIG. 15, it is a refrigerant circuit supposing heating operation, The flow of the refrigerant | coolant at that time is demonstrated.

  The refrigerant is compressed by the compressor 17 to be in a high temperature and high pressure state. The refrigerant in a high temperature and high pressure state flows into the indoor unit 200 through the discharge pipe 20. In the indoor unit 200, the refrigerant radiates heat to a medium such as ambient air or water, and flows into the expansion valve 18 through the indoor unit outlet pipe 21. In the expansion valve 18, the refrigerant becomes a low-temperature and low-pressure gas-liquid two-phase refrigerant and flows into the outdoor unit 100 through the outdoor unit inlet pipe 22. In the outdoor unit 100, the refrigerant absorbs heat from a medium such as ambient air or water, and changes its state from a gas-liquid two-phase state to a gas single-phase state. The refrigerant in the gas single-phase state passes through the suction pipe 19 and returns to the compressor 17. The refrigerant circulates in a general heat pump cycle as described above.

  When the header distributor according to the first to fifth embodiments is used, the pressure loss is increased in the flow path area reducing portion A by the insertion flat tube 2. However, the pressure loss can be dealt with by increasing the opening of the expansion valve 18.

Embodiment 7 FIG.
FIG. 16 shows a refrigerant circuit of the air-conditioning apparatus according to Embodiment 7. In Embodiment 7, in the refrigerant circuit according to Embodiment 6, a gas-liquid separator 24 is provided between the outdoor unit 100 and the expansion valve 18. Furthermore, a bypass circuit for the gas-liquid separator 24 is provided.

  A refrigerant containing a large amount of gas refrigerant flows through the bypass circuit of the gas-liquid separator. On the other hand, the refrigerant mainly containing a large amount of liquid refrigerant flows into the outdoor unit 100 through the outdoor unit inlet pipe 22b.

  A gas bypass LEV (bypass throttle device) 23 is provided on the bypass circuit of the gas-liquid separator. By providing the gas bypass LEV 23, the dryness of the refrigerant flowing into the header distributor can be adjusted, and stable distribution can be performed under a wide range of operating conditions with different refrigerant flow rates. Therefore, the performance of the heat exchanger is improved. Adjustment of the degree of dryness of the gas-liquid separator is performed by, for example, investigating the relationship between the compressor frequency and the opening degree of the gas bypass LEV 23 through a prior experiment, and setting the opening degree of the gas bypass LEV 23 corresponding to the frequency when the air conditioner is operating This can be realized by using such control.

  In the example shown in FIG. 16, a gas bypass LEV 23 is provided on the bypass circuit of the gas-liquid separator 24. However, a thin tube such as a capillary tube may be used as a substitute for the gas bypass LEV23.

  The invention is not limited to the specific details and exemplary embodiments described and described above. Further variations and effects that can be easily derived by those skilled in the art are also included in the present invention. Accordingly, various modifications can be made without departing from the spirit or scope of the general inventive concept as defined by the appended claims and their equivalents.

1 liquid header, 2 inlet inserted flat tube, 3 heat exchanger connection tube, 4a bypass piping, 4b bypass piping, 5a circular tube-flat tube conversion joint, 6a circular tube insertion hole, 7 flat tube insertion hole, 8 refrigerant Channel area, 10 Bypass header, 11 Capillary tube, 12 Bypass branch pipe, 13 Inlet insertion hole, 14 Outdoor heat exchanger, 15 Gas side heat exchange connection pipe, 16 Gas header, 17 Compressor, 18 Expansion valve, 19 Suction piping, 20 discharge piping, 21 indoor unit outlet piping, 100 outdoor units, 200 indoor units.

Claims (7)

A liquid header that has a refrigerant flow path inside and from which the refrigerant flows from one end to the other end;
A plurality of heat exchanger connecting pipes connected to the liquid header between the one end and the other end, and from which the refrigerant is distributed;
A bypass pipe connected to the liquid header on the other end side than a position where the plurality of heat exchanger connecting pipes are connected;
One is connected to the bypass pipe outside the liquid header, and the other is inserted into the liquid header at the inlet portion on the one end side than the position where the plurality of heat exchanger connecting pipes are connected, An inlet portion insertion flat tube that allows the refrigerant to flow from the bypass pipe to the liquid header;
In the liquid header, a cross-sectional area of the refrigerant flow path in a portion where the inlet portion insertion flat tube is inserted is smaller than a cross-sectional area of the refrigerant flow path on the one end side and the other end side of the portion. Characteristic header distributor. The header distributor according to claim 1, further comprising a capillary tube that connects the bypass pipe and the inlet-inserted flat tube. One side is connected to the bypass pipe, and the other inlet side is connected to the other end side of the root part where the inlet part insertion flat tube is inserted into the liquid header in the inlet part, and the refrigerant flowing through the bypass pipe is It further comprises a bypass branch that flows into the liquid header,
The length of the branch pipe that is the length of the part where the bypass branch pipe is inserted into the inside is also short, the length of the flat pipe that is the length of the part where the flat part of the inlet insertion is inserted into the inside,
The distance between the bypass branch pipe and the inlet insertion flat tube is smaller than the difference between the branch tube length and the flat tube length,
The part where the refrigerant flows from the bypass branch pipe to the inside is located on the other end side of the part inserted into the inside of the inlet part insertion flat pipe. Header distributor. The liquid header is a flat tube,
The flat tube includes an inlet insertion tube hole through which the refrigerant flowing through the liquid header passes.
The header distributor according to claim 1, wherein the inlet insertion tube hole is separated from a portion where the refrigerant flows from the inlet portion insertion flat tube to the inside. An outdoor unit comprising the header distributor according to any one of claims 1 to 4. An air conditioner comprising the outdoor unit according to claim 5. An expansion valve;
A gas-liquid separator disposed between the expansion valve and the outdoor unit;
Gas-liquid separator bypass piping,
The air conditioner according to claim 6, further comprising a bypass throttle device.

Images