JP2014126220A - Heat exchanger - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enable enhancement of both the refrigerant evaporation performance and the refrigerant condensation performance of an outdoor heat exchanger of a heat pump device.SOLUTION: A heat exchanger 1 includes a first path P1, a second path P2, and a third path P3 from upstream to downstream in a refrigerant flow direction at a time of condensing refrigerant. Flow of outdoor air to tubes 2 constituting the third path P3 through which the refrigerant flows from downward to upward is blocked.

Description

  The present invention relates to a heat exchanger of a heat pump device.

  Conventionally, for example, a heat pump device has been used as an air conditioner. In the heat pump device, an outdoor heat exchanger acts as a condenser during cooling, and acts as an evaporator during heating (see, for example, Patent Document 1). Considering the heating performance during heating operation as the structure of the outdoor heat exchanger, the header tanks are arranged vertically and the tubes extending in the vertical direction are arranged between the upper and lower header tanks so as to communicate with the header tanks. The structure provided in is preferable. As a result, the condensed water generated on the outer surface of the tube can be smoothly drained downward, improving the heat exchange performance and improving the refrigerant distribution to each tube inside the heat exchanger.

  In addition, in the outdoor heat exchanger, a plurality of paths constituted by a plurality of tube groups are formed so as to be continuous in the refrigerant flow direction. Thereby, the flow velocity of the refrigerant flowing in the tube is increased, and the heat transfer performance is improved.

JP 2001-141382 A

  By the way, the outdoor heat exchanger of a heat pump apparatus has the case where it acts as a condenser as mentioned above, and the case where it acts as an evaporator. When acting as an evaporator, it is possible to improve the evaporation performance by providing the tube so as to extend in the vertical direction and dividing the tube so as to form a plurality of paths.

  However, considering the case where the outdoor heat exchanger acts as a condenser, the structure for improving the evaporation performance may be a cause of hindering the improvement of the condensation performance. That is, when the outdoor heat exchanger acts as a condenser, the high-temperature and high-pressure refrigerant discharged from the compressor flows through the upstream path of the outdoor heat exchanger, and then continues to the intermediate path downstream and the downstream of the intermediate path. The downstream path is distributed in order. While the refrigerant flows through the tubes constituting each path, the refrigerant exchanges heat with the external air to lower the temperature, and gradually condenses. For example, when the flow of the refrigerant in the intermediate path is a flow from the bottom to the top, the refrigerant is condensed while flowing in the intermediate path, and the ratio of the liquid refrigerant increases as it goes to the upper side of the intermediate path. When the ratio of the liquid refrigerant increases, there is a problem that the refrigerant is difficult to rise as a whole, stays in the intermediate path, and consequently reduces the condensation performance.

  This invention is made | formed in view of this point, The place made into the objective is to enable it to improve both the refrigerant | coolant evaporation performance and the condensation performance of the outdoor heat exchanger of a heat pump apparatus.

  In order to achieve the above object, in the present invention, it is made difficult for external air to flow through a path in which the refrigerant flows upward.

The first invention comprises a core in which a plurality of tubes extending in the downward direction are arranged in parallel
An upper header tank that communicates with the upper end of the tube and extends in the direction in which the tubes are juxtaposed,
A lower header tank that communicates with the lower end of the tube and extends in the direction in which the tubes are juxtaposed,
In the heat exchanger for a heat pump device formed so that a path consisting of a plurality of the tube groups is continuous in the refrigerant flow direction by partitioning at least one of the upper and lower header tanks in the juxtaposed direction of the tubes.
At least a first pass, a second pass, and a third pass are formed from the upstream side to the downstream side in the refrigerant flow direction during refrigerant condensation,
Among the first to third passes, the air passage is provided with a ventilation inhibition portion that inhibits the flow of external air to the tube group constituting the upward flow path where the refrigerant flows from the lower side to the upper side. .

  According to this configuration, when the heat exchanger acts as a condenser, the flow of the external air to the tube group constituting the upward flow path in which the refrigerant becomes the upward flow is inhibited by the ventilation blocking portion, so the upward flow path It becomes difficult for the refrigerant flowing through the air to exchange heat with the external air, and it is possible to suppress an increase in the ratio of the liquid refrigerant in the tube of the upward flow path. This makes it difficult for the refrigerant to stay in the upward flow path, so that the condensation performance is improved.

  On the other hand, when the heat exchanger acts as an evaporator, the header tanks are arranged up and down, and the tubes extend in the vertical direction, so that the condensate drainage is improved and the refrigerant flow is also improved. Therefore, the evaporation performance is increased.

According to a second invention, in the first invention,
The path provided with the ventilation block is the third path,
The total flow path cross-sectional area of the tube group constituting the third path is set smaller than the total flow path cross-sectional area of the tube group constituting the second path.

  According to this configuration, since the total flow path cross-sectional area of the path that inhibits the flow of external air is small, it is possible to suppress a decrease in the refrigerant evaporation performance due to the provision of the ventilation inhibition portion.

According to a third invention, in the first or second invention,
The ventilation inhibition part is a wind shielding plate arranged so as to cover the upstream side of the core in the direction of external air flow.

  According to this configuration, it is possible to surely suppress the flow of external air to the upflow path while having a simple configuration.

  According to the first invention, the header tanks are respectively disposed above and below the core having the tubes extending in the vertical direction, and the flow of external air to the tube group constituting the upward flow path in which the refrigerant flows from the lower side to the upper side is inhibited. Thus, both the refrigerant evaporation performance and the condensation performance can be enhanced.

  According to the second aspect of the invention, since the total flow path cross-sectional area of the path provided with the ventilation inhibition portion is reduced, it is possible to suppress a decrease in the refrigerant evaporation performance.

  According to the third aspect of the invention, since the upstream side of the upward flow path in the external air flow direction is covered with the wind shielding plate, the flow of external air to the upward flow path can be reliably suppressed while suppressing an increase in cost.

It is the front view which looked at the heat exchanger which concerns on embodiment of this invention from the external air flow direction upstream. It is a side view of a heat exchanger. It is the III-III sectional view taken on the line of FIG.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. It should be noted that the following description of the preferred embodiment is merely illustrative in nature, and is not intended to limit the present invention, its application, or its use.

  FIG. 1 is a front view of a heat exchanger 1 according to an embodiment of the present invention as viewed from the upstream side in the flow direction of external air. The heat exchanger 1 is used, for example, as a heat exchanger outside a vehicle compartment of a heat pump device of a vehicle air conditioner. Therefore, the heat exchanger 1 acts as an evaporator and as a condenser. There are cases. In the description of this embodiment, the right side of FIG. 1 is the right side of the heat exchanger 1, and the left side of FIG. 1 is the left side of the heat exchanger 1.

  Since the heat pump device (not shown) has a conventionally well-known configuration, a detailed description thereof is omitted, but in addition to the heat exchanger 1 disposed outside the vehicle interior, the vehicle interior heat disposed in the vehicle interior. It consists of an exchanger, a compressor, a four-way valve, an expansion valve, and the like. The vehicle interior heat exchanger is accommodated in an air conditioning casing (not shown) mounted in the vehicle interior, and generates heat of air conditioning by exchanging heat with air conditioning air. In addition to the heat exchanger for a vehicle air conditioner, the present invention can also be used as a heat exchanger for a general air conditioner for home use.

  The heat exchanger 1 is disposed at a core 4 in which a plurality of tubes 2 and fins 3 are alternately arranged, an upper header tank 10 disposed at an upper end portion of the core 4, and a lower end portion of the core 4. The lower header tank 20 is provided.

  As shown in FIG. 3, the tube 2 is a flat tube having a channel cross-sectional shape that is long in the flow direction of external air (the direction indicated by the white arrow), and is made of, for example, an aluminum alloy. A symbol R in FIG. 3 indicates a flow path of the tube 2. Both side surfaces of the tube 2 are formed substantially flat and extend in parallel to each other.

  As shown in FIG. 1, the fin 3 is a corrugated fin formed in a waveform that is continuous in the vertical direction when viewed from the upstream side in the flow direction of the external air. The fin 3 is also made of an aluminum alloy. The fin 3 is brazed to the side surface of the tube 2.

  In addition to the tubes 2 and the fins 3, the core 4 includes end plates 5 disposed at both outer ends of the tubes 2 and the fins 3 in the arrangement direction. The end plate 5 is a flat plate formed so as to cover the fin 3 at the outer end of the core 4 from the side. The end plate 5 is also made of an aluminum alloy and is brazed to the fins 3.

  The upper header tank 10 is made of an aluminum alloy and is formed in a cylindrical shape that extends in the direction in which the tubes 2 and the fins 3 are juxtaposed. A tube insertion hole (not shown) into which the upper end portion of the tube 2 is inserted is formed in the lower wall portion of the upper header tank 10 corresponding to the interval between the tubes 2. The upper end portion of the tube 2 is inserted into the tube insertion hole of the upper header tank 10 and communicates with the upper header tank 10 and is brazed to the peripheral portion of the tube insertion hole.

  An upper partition plate 11 is arranged inside the upper header tank 10. The upper partition plate 11 is for partitioning the inside of the upper header tank 10 into two spaces (left space S1 and right space S2) in the juxtaposition direction of the tubes 2 (longitudinal direction of the header tank 10). It is brazed to the header tank 10. The upper partition plate 11 is disposed in the vicinity of the central portion in the left-right direction of the upper header tank 10.

  Similarly to the upper header tank 10, the lower header tank 20 is also formed in a cylindrical shape extending in the direction in which the tubes 2 and the fins 3 are juxtaposed. A tube insertion hole (not shown) into which the lower end portion of the tube 2 is inserted is formed in the upper wall portion of the lower header tank 20 corresponding to the interval between the tubes 2. The lower end of the tube 2 is inserted into the tube insertion hole of the lower header tank 20 and communicates with the lower header tank 20 and is brazed to the peripheral edge of the tube insertion hole.

  A lower first partition plate 21 and a lower second partition plate 22 are disposed inside the lower header tank 20. The lower first partition plate 21 and the lower second partition plate 22 are for partitioning the inside of the lower header tank 20 into three spaces (left space T1, central space T2, and right space T2) in the longitudinal direction. And is brazed to the lower header tank 20. The lower first partition plate 21 is arranged on the left side of the upper partition plate 11. Further, the lower second partition plate 22 is disposed on the right side of the upper partition plate 11.

  The lower header tank 20 is provided with a left refrigerant pipe 23 for supplying refrigerant and a right refrigerant pipe 24 for discharging refrigerant. The left refrigerant pipe 23 is a pipe that communicates with the left space T1 of the lower header tank 20, and is connected to other devices that constitute the heat pump device. The right refrigerant pipe 24 is a pipe that communicates with the right space T3 of the lower header tank 20, and is connected to other devices that constitute the heat pump device.

  First to fourth paths P <b> 1 to P <b> 4 are formed in the heat exchanger 1 by the upper partition plate 11, the lower first partition plate 21, and the lower second partition plate 22. The first to fourth paths P1 to P4 are connected in series and continue in the flow direction of the refrigerant. The first path P1 is located on the leftmost side of the heat exchanger 1, the second path P2 is adjacent to the right side of the first path P1, the third path P3 is adjacent to the right side of the second path P2, and the fourth path P4. Is located on the right side of the heat exchanger 1 adjacent to the right side of the third path P3.

  The flow path cross-sectional areas of the first to fourth paths P1 to P4 can be changed according to the number of tubes 2 constituting each of the paths P1 to P4. The number of tubes 2 constituting each of the paths P1 to P4 can be changed depending on the positions of the upper partition plate 11, the lower first partition plate 21, and the lower second partition plate 22, and in this embodiment, the third The total flow path cross-sectional area of the tubes 2 constituting the path P3 is set smaller than the total flow path cross-sectional area of each tube 2 in the first path P1, the second path P2, and the fourth path P4.

  In addition, the heat exchanger 1 includes a wind shielding plate (ventilation inhibiting portion) 30 that inhibits the flow of external air to the tube 2 constituting the third path P3. The wind shielding plate 30 is sized to cover the third path P3 in the core 4, and is arranged so as to cover the third path P3 from the upstream side in the flow direction of the external air, and is fixed to the core 4. Yes. The upper part of the wind shielding plate 30 extends to the vicinity of the upper end of the core 4, and the lower part of the wind shielding plate 30 extends to the vicinity of the lower end of the core 4. The left edge of the wind shield 30 is located near the left edge of the third path 3, and the right edge of the wind shield 30 is located near the right edge of the third path 3. Thereby, substantially the entire third path P3 can be covered with the wind shielding plate 30.

  The wind shielding plate 30 can be made of, for example, an aluminum alloy plate. In this case, the wind shielding plate 30 can be brazed and fixed to the tube 2 or the fin 3 of the core 4. Moreover, you may make it fix the windshield 30 to the core 4 or the header tanks 10 and 20 using welding, a fastening member, etc., for example. Further, the wind shield plate 30 may be made of a resin material, for example.

  Next, the case where the heat exchanger 1 configured as described above is used as an outside heat exchanger of a vehicle air conditioner will be described.

  During heating, the heat exchanger 1 acts as an evaporator. In other words, the refrigerant that has been decompressed through the expansion valve flows into the left refrigerant pipe 23, and the refrigerant flows into the left space T <b> 1 of the lower header tank 20. The refrigerant flowing into the left space T1 flows from the lower side to the upper side of the tube 2 constituting the first path P1 and flows into the left side space S1 of the upper header tank 10 and then flows into the upper side of the tube 2 constituting the second path P2. From below to the central space T2 of the lower header tank 20. The refrigerant flowing into the central space T2 flows from the lower side to the upper side of the tube 2 constituting the third path P3 and flows into the right side space S2 of the upper header tank 10, and then enters the upper side of the tube 2 constituting the fourth path P4. From the right side to the right side space T3 of the lower header tank 20 and then discharged to the outside from the right side refrigerant pipe 24.

  When the heat exchanger 1 acts as an evaporator, the refrigerant evaporates while exchanging heat with external air while flowing through the tubes 2 of the first to fourth paths P1 to P4. At this time, condensed water is generated on the outer surface of the tube 2. Since the tube 2 extends in the vertical direction, the generated condensed water flows downward along the outer surface of the tube 2. Therefore, drainage becomes good and heat exchange efficiency increases. Further, the refrigerant flow from the upper header tank 10 to each tube 2 and the refrigerant flow from the lower header tank 20 to each tube 2 are high, and thus the evaporation performance is improved.

  In addition, when the heat exchanger 1 acts as an evaporator, the third path P3 is covered with the wind shield plate 30, so that the third path P3 hardly exchanges heat with external air. As described above, since the total cross-sectional area of the tube 2 in the third path P3 is smaller than those of the other paths P1, P2, and P4, the influence thereof is small.

  On the other hand, during cooling, the heat exchanger 1 acts as a condenser. That is, the high-temperature high-pressure refrigerant discharged from the compressor flows into the left refrigerant pipe 23, and this refrigerant flows into the left space T <b> 1 of the lower header tank 20. The refrigerant that has flowed into the left space T <b> 1 flows through the first to fourth paths P <b> 1 to P <b> 4 and then is discharged to the outside from the right refrigerant pipe 24, as in the case of acting as an evaporator.

  When the heat exchanger 1 acts as a condenser, the refrigerant condenses while exchanging heat with external air while flowing through the tubes 2 of the first to fourth paths P1 to P4. At this time, the flow of the external air to the tube 2 constituting the third path P3 (upflow path) in which the refrigerant becomes an upward flow is inhibited by the wind shield plate 30, so the refrigerant flowing through the third path P3 Becomes difficult to exchange heat with external air, and it becomes possible to suppress an increase in the proportion of the liquid refrigerant in the tube 2 of the third path P3. Thereby, since it becomes difficult for a refrigerant | coolant to stay in the 3rd path | pass P3, a condensation performance improves. Moreover, since the total flow path cross-sectional area of the 3rd path | pass P3 which blocks | prevents the flow of external air is smaller than the other path | pass P1, P2, P4, the fall of the refrigerant | coolant condensing performance by providing the wind-shielding board 30 is suppressed. It becomes possible.

  As described above, according to the heat exchanger 1 according to this embodiment, the header tanks 10 and 20 are arranged above and below the core 4 having the tubes 2 extending in the vertical direction, respectively, and the refrigerant flows from the lower side to the upper side. Since the flow of external air to the tube 2 constituting the third path P3 is inhibited, both the refrigerant evaporation performance and the condensation performance can be enhanced.

  Moreover, since the total flow path cross-sectional area of the 3rd path | pass P3 in which the wind shield 30 is provided was made small, the fall of a refrigerant | coolant evaporation performance can be suppressed.

  Further, since the upstream side in the external air flow direction of the third path P3 is covered with the wind shield plate 30, the flow of external air to the third path P3 can be reliably suppressed while suppressing an increase in cost.

  In addition, in the said embodiment, although the wind-shielding board 30 is used as a ventilation inhibition part, it is not restricted to this, The flow of the external air to the tube 2 which comprises the 3rd path | pass P3 can be inhibited. What is necessary is just to be a net | network etc., for example.

  Moreover, in the said embodiment, although the substantially whole 3rd path | pass P3 is covered with the windshield plate 30, it is not restricted to this, Only a part of 3rd path | pass P3 is covered with the windshield plate 30. Also good.

  Further, the number of paths is not limited to the number described above, and can be set to an arbitrary number of three or more.

  The above-described embodiment is merely an example in all respects and should not be interpreted in a limited manner. Further, all modifications and changes belonging to the equivalent scope of the claims are within the scope of the present invention.

  As described above, the heat exchanger according to the present invention can be used as, for example, an outdoor heat exchanger of a vehicle air conditioner.

DESCRIPTION OF SYMBOLS 1 Heat exchanger 2 Tube 3 Fin 4 Core 10 Upper header tank 20 Lower header tank 30 Wind shield (ventilation inhibition part)
P1 1st path P2 2nd path P3 3rd path (upflow path)
P4 4th pass

Claims (3)

A core in which a plurality of tubes extending in the vertical direction are arranged in parallel;
An upper header tank that communicates with the upper end of the tube and extends in the direction in which the tubes are juxtaposed,
A lower header tank that communicates with the lower end of the tube and extends in the direction in which the tubes are juxtaposed,
In the heat exchanger for a heat pump device formed so that a path consisting of a plurality of the tube groups is continuous in the refrigerant flow direction by partitioning at least one of the upper and lower header tanks in the juxtaposed direction of the tubes.
At least a first pass, a second pass, and a third pass are formed from the upstream side to the downstream side in the refrigerant flow direction during refrigerant condensation,
Among the first to third paths, a heat exchanger comprising a ventilation inhibition portion that inhibits the flow of external air to the tube group constituting the upward flow path in which the refrigerant flows from the lower side to the upper side. . The heat exchanger according to claim 1,
The path provided with the ventilation block is the third path,
The heat exchanger according to claim 1, wherein a total flow cross-sectional area of the tube group constituting the third path is set smaller than a total flow cross-sectional area of the tube group constituting the second path. The heat exchanger according to claim 1 or 2,
The ventilation block is a wind shield arranged so as to cover the upstream side of the core in the direction of external air flow.

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