JP2013002773A - Heat exchanger and air conditioner with the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a side flow system parallel flow type heat exchanger capable of properly gas-liquid mixing a refrigerant and allowing the same to diverge even when the received refrigerant is in a gas-liquid mixing state.SOLUTION: This parallel flow type heat exchanger 1 includes a refrigerant inflow-side header pipe 2 and a refrigerant outflow-side header pipe 3 disposed in the vertical direction, and a plurality of horizontal flat tubes 4 connecting both header pipes. A refrigerant supply pipe 9 is inserted into the refrigerant inflow-side header pipe 2 from a lower end toward an upper end, or from the upper end toward the lower end. The refrigerant supply pipe 9 has a discharge opening 12 opposed to a collision surface 13 formed on an end of the refrigerant inflow-side header pipe 2 at prescribed intervals.

Description

  The present invention relates to a side flow parallel flow heat exchanger and an air conditioner equipped with the heat exchanger.

  A parallel flow type heat exchange in which a plurality of flat tubes are arranged between two header pipes so that a refrigerant passage inside the flat tubes communicates with the header pipe, and fins such as corrugated fins are arranged between the flat tubes. The equipment is widely used in car air conditioners and building air conditioners.

  In a parallel flow type heat exchanger, it is an important design matter to improve heat exchange efficiency so that the refrigerant flows evenly through a plurality of flat tubes. An example of a parallel flow type heat exchanger pursuing an even flow of refrigerant can be seen in Patent Documents 1 and 2.

  A parallel flow heat exchanger described in Patent Document 1 includes a cylindrical hollow header, a refrigerant inlet pipe connected to the refrigerant inflow chamber of the header, and a plurality of tubes connected to the refrigerant inflow chamber. Prepare. The refrigerant inflow chamber is divided into a plurality of inflow partition chambers, the refrigerant inlet pipe is branched into a corresponding number of branch pipes, and the branch pipes are connected to the inflow partition chambers so that the refrigerant is evenly divided into the tubes. Let

  The parallel flow heat exchanger described in Patent Document 2 has a configuration in which a vertical tube is combined with a horizontal header. In the lower header, a refrigerant dispersion pipe that communicates with the refrigerant inlet pipe is disposed along the length direction thereof. A plurality of refrigerant dispersion holes are provided in the peripheral wall of the refrigerant dispersion tube so that the liquid refrigerant flowing into the lower header through the refrigerant inlet pipe is evenly distributed to the tubes.

JP-A-6-74609 Japanese Patent Laid-Open No. 6-159983

  The refrigerant flowing into the parallel flow type heat exchanger is often in a gas-liquid mixed state. In the case of the parallel flow heat exchanger described in Patent Document 1, when a refrigerant in a gas-liquid mixed state flows into the inflow partition chamber, a large amount of liquid flows in a certain tube and a large amount of gas flows in a certain tube. And the heat exchange efficiency decreases. In addition, the parallel flow heat exchanger described in Patent Document 1 has a complicated structure and is expensive to implement.

  The parallel flow heat exchanger described in Patent Document 2 is a downflow system, and when it is converted to a sideflow system, a drift occurs. That is, the gas refrigerant flows upward and the liquid refrigerant flows downward under the influence of gravity, but in the downflow method, the direction of the tube coincides with the direction of gravity. It is only in the range of the inner diameter of the cross section. Therefore, there is little gas-liquid separation due to the influence of gravity.

  However, in the case of the side flow method, gas and liquid are separated in the axial direction of the header pipe. Therefore, separation of gas and liquid is easy to proceed. Even if the refrigerant dispersion hole is provided in the refrigerant dispersion tube in the header as in the parallel flow heat exchanger described in Patent Document 2, the gas and liquid refrigerant separated in the header are affected by gravity. Only the liquid refrigerant goes to the lower tube, and only the gaseous refrigerant goes to the upper tube.

  The present invention has been made in view of the above points, and even if the received refrigerant is in a gas-liquid mixed state, the side-flow parallel-flow-type heat exchange that can appropriately mix and divert the refrigerant in a gas-liquid mixture state. The purpose is to provide a vessel.

  A parallel flow heat exchanger according to the present invention includes a refrigerant inflow header pipe and a refrigerant outflow header pipe arranged in a vertical direction, and a plurality of horizontal flat tubes connecting the both header pipes. A refrigerant supply pipe is inserted into the side header pipe from the lower end to the upper end, or from the upper end to the lower end, and the refrigerant supply pipe is formed on a collision surface formed at an end of the refrigerant inflow side header pipe. It has discharge ports facing each other at a predetermined interval.

  In the parallel flow heat exchanger configured as described above, it is preferable that the discharge port is formed only at a tip of the refrigerant supply pipe.

  In the parallel flow heat exchanger configured as described above, it is preferable that the collision surface is a plane perpendicular to the axis of the refrigerant supply pipe.

  In the parallel flow heat exchanger configured as described above, it is preferable that the collision surface is a convex surface with respect to the discharge port.

  In the parallel flow type heat exchanger configured as described above, it is preferable that a tip of the convex surface enters the discharge port.

  In the parallel flow type heat exchanger configured as described above, the collision surface is preferably concave with respect to the discharge port.

  In the parallel flow heat exchanger configured as described above, it is preferable that the refrigerant supply pipe is disposed in the refrigerant inflow header pipe in a direction away from the flat tube.

  In the parallel flow heat exchanger configured as described above, it is preferable that a refrigerant diffuser is disposed in a gap between the outer peripheral surface of the refrigerant supply pipe and the inner peripheral surface of the refrigerant inflow header pipe.

  According to the present invention, the parallel flow heat exchanger configured as described above is mounted on an indoor unit or an outdoor unit of an air conditioner.

  When the refrigerant discharged from the discharge port of the refrigerant supply pipe collides with the collision surface, mixing of gas and liquid is improved. In addition, when the refrigerant collides with the collision surface, the refrigerant diffuses cleanly, and the flow to each flat tube is improved, so that the heat exchange efficiency is improved.

It is a principal part sectional front view of the heat exchanger concerning a 1st embodiment of the present invention. FIG. 2 is a vertical cross-sectional view of a heat exchanger cut along a line II-II in FIG. 1. It is an expanded horizontal sectional view of a refrigerant inflow side header pipe. It is a partial expanded vertical sectional view of a refrigerant inflow side header pipe. It is a partial expanded vertical sectional view which shows the other example of a refrigerant | coolant inflow side header pipe. It is a partial expanded vertical sectional view which shows the other example of a refrigerant | coolant inflow side header pipe. It is a partial expanded vertical sectional view which shows the other example of a refrigerant | coolant inflow side header pipe. It is a partial expanded vertical sectional view which shows the other example of a refrigerant | coolant inflow side header pipe. It is a principal part sectional front view of the heat exchanger concerning a 2nd embodiment of the present invention. It is an expanded horizontal sectional view of the refrigerant inflow side header pipe in the heat exchanger of a 2nd embodiment. It is a principal part sectional front view of the heat exchanger concerning a 3rd embodiment of the present invention. It is an expanded horizontal sectional view which shows the other example of a refrigerant | coolant inflow side header pipe. It is a schematic block diagram of the air conditioner carrying the heat exchanger which concerns on this invention, and shows the state at the time of heating operation. It is a schematic block diagram of the air conditioner carrying the heat exchanger which concerns on this invention, and shows the state at the time of air_conditionaing | cooling operation.

  The structure of the side flow parallel flow heat exchanger according to the first embodiment of the present invention will be described with reference to FIG. In FIG. 1, the upper side of the paper is the upper side in the vertical direction, and the lower side of the paper is the lower side in the vertical direction.

  The parallel flow type heat exchanger 1 is a side flow type, and includes two vertical header pipes 2 and 3 and a plurality of horizontal flat tubes 4 disposed therebetween. The header pipes 2 and 3 are arranged in parallel in the horizontal direction at intervals, and the flat tubes 4 are arranged at a predetermined pitch in the vertical direction. Since the parallel flow type heat exchanger 1 is installed at various angles according to design requirements at the stage of actually mounting on equipment, “vertical direction” and “horizontal direction” in this specification should not be strictly interpreted. Absent. It should be understood as a mere measure of direction.

  When used as an evaporator (for example, an indoor unit during cooling operation or an outdoor unit during heating operation), the header pipe 2 serves as a refrigerant inflow header pipe, and the header pipe 3 serves as a refrigerant outflow header pipe. Hereinafter, in this specification, the description will proceed with the header pipe 2 as the refrigerant inflow side header pipe and the header pipe 3 as the refrigerant outflow side header pipe.

  The flat tube 4 is an elongated molded product obtained by extruding a metal, and as shown in FIG. 2, a refrigerant passage 5 through which a refrigerant flows is formed. Since the flat tube 4 is disposed so that the extrusion direction, which is the longitudinal direction, is horizontal, the refrigerant flow direction of the refrigerant passage 5 is also horizontal. A plurality of refrigerant passages 4 having the same cross-sectional shape and cross-sectional area are arranged in the left-right direction in FIG. 2, and therefore the vertical cross section of the flat tube 4 has a harmonica shape. Each refrigerant passage 5 communicates with the inside of the refrigerant inflow side header pipe 2 and the refrigerant outflow side header pipe 3.

  Corrugated fins 6 are arranged between the adjacent flat tubes 4. Of the corrugated fins 6 arranged in the vertical direction, side plates 7 are arranged outside the uppermost and lowermost ones.

  The refrigerant inflow side header pipe 2, the refrigerant outflow side header pipe 3, the flat tubes 4, the corrugated fins 6, and the side plates 7 are all made of a metal having good heat conductivity such as aluminum, and the flat tubes 4 are connected to the refrigerant inflow side header pipe 2. The corrugated fin 6 is fixed to the flat tube 4 and the side plate 7 is fixed to the corrugated fin 6 by brazing or welding to the refrigerant outflow side header pipe 3.

  One refrigerant outflow pipe 8 is connected to the refrigerant outflow side header pipe 3. A refrigerant supply pipe 9 is inserted into the refrigerant inflow header pipe 2 from the lower end toward the upper end. As shown in FIG. 3, the refrigerant inflow side header pipe 2 and the refrigerant supply pipe 9 are both circular in cross section and arranged coaxially. The refrigerant supply pipe 9 is made of the same material as the refrigerant inflow side header pipe 2, and is fixed to the end plate 10 forming the lower end of the refrigerant inflow side header pipe 2 by brazing or welding.

  The upper end, that is, the front end of the refrigerant supply pipe 9 faces the end plate 11 that forms the upper end of the refrigerant inflow header pipe 2 with a predetermined interval. The refrigerant supply pipe 9 has a discharge port 12 only at the tip. The refrigerant discharged from the discharge port 12 collides with the lower surface of the end plate 11. That is, the lower surface of the end plate 11 becomes a collision surface 13 on which the refrigerant collides. The collision surface 13 is a plane orthogonal to the axis of the refrigerant supply pipe 9. By forming the discharge port 12 only at the tip of the refrigerant supply pipe 9, all the refrigerant flowing in can collide with the collision surface 13.

  The function of the parallel flow type heat exchanger 1 is as follows. When the refrigerant is fed into the refrigerant supply pipe 9, the refrigerant is discharged from the discharge port 12. The discharged refrigerant collides with the collision surface 13. Gas-liquid mixing is performed by collision. The gas-liquid mixed refrigerant flows down the gap between the outer peripheral surface of the refrigerant supply pipe 9 and the inner peripheral surface of the refrigerant inflow side header pipe 2 and travels toward the refrigerant passage 5 of the flat tube 4. The refrigerant diffuses cleanly, improving the heat exchange efficiency. When the gas-liquid mixed refrigerant flows from the upper part, even if a part of the refrigerant inflow header pipe 2 is gas-liquid separated, the liquid refrigerant is transferred to the refrigerant passage 5 because it is a gas-liquid mixed refrigerant in the upper part. In the lower part, the liquid refrigerant that has been gas-liquid separated easily flows into the refrigerant passage 5, and the flow rate of the liquid refrigerant is balanced at the upper and lower parts, thereby preventing the heat exchange efficiency from being lowered. In addition, the refrigerant supply pipe 9 entering the refrigerant inflow side header pipe 2 reduces the internal volume of the refrigerant inflow side header pipe 2 and reduces the retention of liquid refrigerant, which also effectively improves the heat exchange efficiency. .

  In FIG. 1, the refrigerant supply pipe 9 is inserted from the lower end of the refrigerant inflow side header pipe 2, but the refrigerant supply pipe 9 may be inserted from the upper end of the refrigerant inflow side header pipe 2. In this case, the upper surface of the lower end plate 10 constitutes the collision surface 13.

  Gas-liquid mixing is also performed when the refrigerant collides with the collision surface 13 of the lower end plate 10. The gas-liquid mixed refrigerant rises in the gap between the outer peripheral surface of the refrigerant supply pipe 9 and the inner peripheral surface of the refrigerant inflow side header pipe 2 and moves toward the refrigerant passage 5 of the flat tube 4. As the sufficiently gas-liquid mixed refrigerant rises, the liquid refrigerant diffuses cleanly in all the flat tubes 4. This balances the flow rate of the liquid refrigerant at the top and bottom, and prevents a decrease in heat exchange efficiency.

  The shape of the shape of the collision surface 13 is not limited to a plane. Various shapes are possible, as illustrated in FIGS.

  The collision surface 13 shown in FIG. 5 is convex with respect to the discharge port 12. Specifically, a cone-shaped body such as a triangular pyramid, a quadrangular pyramid, or a cone forms a convex surface, and its tip is directed to the discharge port 12. The refrigerant hitting the tip of the convex surface is quickly mixed and diffused to reach the inner peripheral surface of the refrigerant inflow side header pipe 2, where the flow direction is changed downward.

  A collision surface 13 shown in FIG. 6 is a modification of the convex surface of FIG. Here, the convex surface is formed thin, and the tip of the convex surface enters the discharge port 12. In this structure, when the refrigerant supply pipe 9 swings, there is an advantage that the inner surface of the discharge port 12 hits the collision surface 13 and the swing width is suppressed. Further, since the refrigerant reliably collides with the convex surface, the refrigerant is likely to diffuse. The refrigerant supply pipe 9 entering the inside of the refrigerant inflow side header pipe 2 reduces the internal volume of the refrigerant inflow side header pipe 2 and reduces the retention of liquid refrigerant, which also effectively improves the heat exchange efficiency.

  Although the collision surface 13 shown in FIG. 7 is also a convex surface with respect to the discharge port 12, the convex surface is a part of a spherical surface. The refrigerant hitting the center of the convex surface is quickly mixed and diffused to reach the inner peripheral surface of the refrigerant inflow side header pipe 2, where the flow direction is changed downward.

  The collision surface 13 shown in FIG. 8 is concave with respect to the discharge port 12. The concave surface is a part of a spherical surface. The refrigerant that hits the center of the concave surface changes its flow direction downward while mixing and diffusing.

  9 and 10 show a modified embodiment relating to the arrangement of the refrigerant supply pipe 9 inside the refrigerant inflow header pipe 2. In this embodiment, the refrigerant supply pipe 9 is arranged in the refrigerant inflow header pipe 2 in a direction away from the flat tube 4. Thereby, the space | interval of the refrigerant path 5 and the refrigerant supply pipe 9 becomes wide, and it becomes easy for a refrigerant | coolant to flow in into the refrigerant path 5. FIG.

  FIG. 11 shows another structure that helps to improve shunting. That is, the gas-liquid diffuser 14 is disposed in the gap between the outer peripheral surface of the refrigerant supply pipe 9 and the inner peripheral surface of the refrigerant inflow side header pipe 2. As the gas-liquid diffuser 14, for example, steel wool can be used. Although only the upper part of the refrigerant inflow side header pipe 2 is shown in FIG. 11, the gas-liquid diffuser 14 is packed from a position slightly lower than the front end of the refrigerant supply pipe 9 to the lower end of the refrigerant inflow side header pipe 2. Is.

  By disposing the gas-liquid diffuser 14 in the gap between the outer peripheral surface of the refrigerant supply pipe 9 and the inner peripheral surface of the refrigerant inflow header pipe 2, the tendency of the refrigerant to concentrate on some of the flat tubes 4 is suppressed. The refrigerant distribution to each flat tube 4 is further leveled.

  The collision surface 13 depicted in FIGS. 9 and 11 is planar, but it goes without saying that it may be a convex surface or a concave surface.

  In FIG. 12, the example of improvement regarding the shape of the edge part connected to the refrigerant | coolant inflow side header pipe 2 in the flat tube 4 is shown. Here, the end surface of the flat tube 4 is a curved surface having the same curvature as the inner peripheral surface of the refrigerant inflow side header pipe 2, and the flat tube 4 does not protrude from the inner peripheral surface of the refrigerant inflow side header pipe 2. Thereby, the refrigerant | coolant flow of the axial direction inside the refrigerant | coolant inflow side header pipe 2 can be made smooth. A similar structure can be applied to the refrigerant outflow side header pipe 3.

  12, similarly to the modified embodiments shown in FIGS. 9 and 10, the refrigerant supply pipe 9 can be arranged in the refrigerant inflow header pipe 2 in a direction away from the flat tube 4. By doing so, the interval between the refrigerant passage 5 and the refrigerant supply pipe 9 is widened, and the refrigerant easily flows into the refrigerant passage 5.

  The parallel flow heat exchanger 1 can be mounted on a separate air conditioner. A separate type air conditioner is composed of an outdoor unit and an indoor unit. The outdoor unit includes a compressor, a four-way valve, an expansion valve, an outdoor heat exchanger, an outdoor fan, and the like. The indoor unit is an indoor heat exchanger, a room Includes an internal blower. The outdoor heat exchanger functions as an evaporator during heating operation and functions as a condenser during cooling operation. The indoor heat exchanger functions as a condenser during heating operation and functions as an evaporator during cooling operation.

  FIG. 13 shows a basic configuration of a separate type air conditioner that uses a heat pump cycle as a refrigeration cycle. The heat pump cycle 101 includes a compressor 102, a four-way valve 103, an outdoor heat exchanger 104, a decompression / expansion device 105, and an indoor heat exchanger 106 connected in a loop. The compressor 102, the four-way valve 103, the heat exchanger 104, and the decompression / expansion device 105 are accommodated in the casing of the outdoor unit, and the heat exchanger 106 is accommodated in the casing of the indoor unit. An outdoor fan 107 is combined with the heat exchanger 104, and an indoor fan 108 is combined with the heat exchanger 106. The blower 107 includes a propeller fan, and the blower 108 includes a cross flow fan.

  The side flow type parallel flow heat exchanger 1 according to the present invention can be used as a component of the heat exchanger 106 of an indoor unit. The heat exchanger 106 is a combination of three heat exchangers 106A, 106B, 106C like a roof that covers the blower 108, and any one of the heat exchangers 106A, 106B, 106C is a parallel flow heat exchanger. 1 can be used.

  FIG. 13 shows a state during heating operation. At this time, the high-temperature and high-pressure refrigerant discharged from the compressor 102 enters the indoor heat exchanger 106 where it dissipates heat and condenses. The refrigerant exiting the heat exchanger 106 enters the outdoor heat exchanger 104 from the decompression / expansion device 105 and expands there, takes heat from the outdoor air, and returns to the compressor 102. The airflow generated by the indoor fan 108 promotes heat dissipation from the heat exchanger 106, and the airflow generated by the outdoor fan 107 accelerates heat absorption of the heat exchanger 104.

  FIG. 14 shows a state during cooling operation or defrosting operation. At this time, the four-way valve 103 is switched so that the refrigerant flow is reversed from that during the heating operation. That is, the high-temperature and high-pressure refrigerant discharged from the compressor 102 enters the outdoor heat exchanger 104, where it dissipates heat and condenses. The refrigerant exiting the heat exchanger 104 enters the heat exchanger 106 on the indoor side from the decompression / expansion device 105 and expands there, takes heat from indoor air, and returns to the compressor 102. The airflow generated by the outdoor fan 107 promotes heat dissipation from the heat exchanger 104, and the airflow generated by the indoor fan 108 promotes heat absorption of the heat exchanger 106.

  The parallel flow type heat exchanger 1 can also be used as a heat exchanger 104 for an outdoor unit.

  Although the embodiments of the present invention have been described above, the scope of the present invention is not limited to these embodiments, and various modifications can be made without departing from the spirit of the invention. For example, when the tip of the refrigerant supply pipe has an inverted U shape and the apex portion of the inverted U shape faces the end plate, a shape in which a discharge port is provided at the apex portion is also possible.

  The present invention is widely applicable to side flow parallel flow heat exchangers.

DESCRIPTION OF SYMBOLS 1 Parallel flow type heat exchanger 2 Refrigerant inflow side header pipe 3 Refrigerant outflow side header pipe 4 Flat tube 5 Refrigerant passage 6 Corrugated fin 7 Side plate 8 Refrigerant outflow pipe 9 Refrigerant supply pipe 10, 11 End plate 12 Discharge port 13 Collision surface 14 Refrigerant diffuser

Claims (9)

In a parallel flow type heat exchanger of a side flow system comprising a refrigerant inflow side header pipe and a refrigerant outflow side header pipe arranged in a vertical direction, and a plurality of horizontal flat tubes connecting the both header pipes,
A refrigerant supply pipe is inserted into the refrigerant inflow side header pipe from the lower end toward the upper end or from the upper end toward the lower end, and the refrigerant supply pipe is formed at an end of the refrigerant inflow side header pipe. A parallel flow type heat exchanger having discharge ports facing each other at a predetermined interval on the collision surface.   The parallel flow type heat exchanger according to claim 1, wherein the discharge port is formed only at a tip of the refrigerant supply pipe.   The parallel flow heat exchanger according to claim 1 or 2, wherein the collision surface is a plane orthogonal to an axis of the refrigerant supply pipe.   The parallel flow heat exchanger according to claim 1 or 2, wherein the collision surface is convex with respect to the discharge port.   The parallel flow heat exchanger according to claim 4, wherein a tip of the convex surface enters the discharge port.   The parallel flow heat exchanger according to claim 1, wherein the collision surface is concave with respect to the discharge port.   The parallel flow type according to any one of claims 1 to 6, wherein the refrigerant supply pipe is arranged in the refrigerant inflow header pipe so as to be deviated in a direction away from the flat tube. Heat exchanger.   8. The refrigerant diffuser according to claim 1, wherein a refrigerant diffuser is disposed in a gap between the outer peripheral surface of the refrigerant supply pipe and the inner peripheral surface of the refrigerant inflow side header pipe. Parallel flow heat exchanger.   An air conditioner in which the parallel flow heat exchanger according to any one of claims 1 to 8 is mounted on an indoor unit or an outdoor unit.

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