JP2004316976A - Heat exchanger - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To enhance durability of a heat exchanger by preventing corrosion of a joining place of the tube inserting hole peripheral edge and a tube outer peripheral surface of a header tank. <P>SOLUTION: Swelling parts 14 and 15 are formed in a tube lower end corresponding place of an upper wall part 12a of the lower side header tank 9. Tube inserting holes 14a and 15a are formed in the swelling parts 14 and 15. Guide surfaces 14b and 15b extending downward to the outside of the tube inserting holes 14a and 15a, are formed on an outside surface of the swelling parts 14 and 15. Condensate falling down on the peripheral edge of the tube inserting holes 14a and 15a by going along a tube when cooled by air, is conducted outside by these guide surfaces 14b and 15b. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a heat exchanger used as an evaporator that constitutes one element of a refrigeration cycle of an air conditioner, for example.
[0002]
[Prior art]
Conventionally, as a heat exchanger of this type, a plurality of vertically extending tubes and fins are alternately arranged side by side in a direction intersecting with the air flow direction to constitute a core, and a tube end portion is provided at an upper end and a lower end of the core. There is known a heat exchanger in which an upper header tank and a lower header tank which communicate with each other are arranged (for example, see Patent Document 1).
[0003]
In the heat exchanger of Patent Document 1, the upper wall of the lower header tank is formed in a substantially horizontal flat surface, and a tube insertion hole for inserting and holding the lower end of the tube of the core is formed in the upper wall. The periphery of the tube insertion hole and the outer peripheral surface of the tube are brazed.
[0004]
During the operation of the refrigeration cycle, the heat exchange medium in a condensed state flows through the expansion valve into, for example, the lower header tank, and the heat exchange medium in the lower header tank flows into each tube. The heat exchange medium in the tube and the surrounding air are subjected to heat exchange to generate cool air.
[0005]
[Patent Document 1]
JP 2001-235296 A (Page 3, Page 4, FIG. 1, FIG. 3)
[0006]
[Problems to be solved by the invention]
By the way, in the heat exchanger of Patent Document 1, condensed water generated on the surfaces of the tubes and the fins when cooling the air flows down the tubes and into the periphery of the tube insertion holes in the upper wall of the lower header tank.
[0007]
However, in the heat exchanger of Patent Document 1, since the upper wall of the lower header tank is formed in a substantially horizontal flat surface, when the condensed water that has flowed down as described above remains at the periphery of the tube insertion hole, There is a possibility that the joint between the peripheral edge of the tube insertion hole and the outer peripheral surface of the tube may be corroded early and the durability of the heat exchanger may be reduced.
[0008]
The present invention has been made in view of such a point, and an object thereof is to set a shape of a header tank upper wall portion in which condensed water flowing down along a tube does not remain at the periphery of the tube insertion hole. Another object of the present invention is to improve the durability of the heat exchanger by preventing corrosion at the joint between the periphery of the tube insertion hole and the outer peripheral surface of the tube.
[0009]
[Means for Solving the Problems]
In order to achieve the above object, in the solution of the present invention, the guide surface formed on the upper wall of the header tank guides condensed water flowing down to the periphery of the tube insertion hole to the outside of the tube insertion hole.
[0010]
Specifically, according to the first aspect of the present invention, a tube group in which a plurality of vertically extending tubes are juxtaposed in a direction intersecting with the air flow direction, and a tube group disposed at the lower end of the tube group and formed on the upper wall portion A tube tank is inserted and held in the inserted tube insertion hole, and a header tank is provided with each tube end communicating therewith.The heat exchange medium flowing through each tube and the surrounding air exchange heat with each other to remove the air. For a heat exchanger configured to cool.
[0011]
The upper wall of the header tank extends downward from the periphery of each tube insertion hole toward the outside of the tube insertion hole, and condensed water that falls along the tube when the air is cooled flows out of the periphery of the tube insertion hole. To form a guide surface leading to the
[0012]
According to this configuration, when condensed water generated on the tube surface when cooling the surrounding air flows down to the periphery of the tube insertion hole on the upper wall of the header tank, the condensed water on the periphery of the tube insertion hole is removed from the tube insertion hole. The guide surface descends outward and is guided and discharged without remaining at the periphery of the tube insertion hole. This prevents corrosion at the joint between the periphery of the tube insertion hole and the outer peripheral surface of the tube, and enhances the durability of the heat exchanger.
[0013]
According to a second aspect of the present invention, in the first aspect of the invention, each tube insertion hole forming portion of the header tank upper wall portion bulges upward, and the bulging portion outer surface forms a guide surface.
[0014]
According to this configuration, since the guide surface is formed from the outer surface of the bulging portion and the rigidity of the upper wall portion of the header tank is improved, sufficient pressure resistance can be obtained without increasing the thickness of the constituent members of the header tank. The weight of the exchanger can be reduced.
[0015]
When the heat exchange medium is caused to flow from one end side of the header tank in the tube juxtaposition direction, the heat exchange medium flows to the other end side of the header tank in the tube juxtaposition direction depending on the height of the swelling portion. Can be controlled. Thereby, the heat exchange medium flows into each tube without bias, and the temperature distribution of the air blown out from the heat exchanger is made uniform.
[0016]
According to a third aspect of the present invention, in the first or second aspect of the present invention, the header tank extends in the direction in which the tubes are arranged, and an inflow pipe through which a heat exchange medium flows into the header tank is connected to one longitudinal end of the header tank. Inside the header tank, a control plate for controlling the flow of the heat exchange medium flowing from the inflow pipe and flowing through the tank is provided, and a guide surface adjacent to the header tank upper wall in the tube juxtaposition direction. A flat portion extending in the direction of air flow is formed between them, and the control plate is brazed to a portion corresponding to the flat portion on the inner peripheral surface of the header tank.
[0017]
According to this configuration, the flow of the heat exchange medium flowing into the header tank from the inflow pipe is controlled by the control plate, so that the heat exchange medium flows into each tube without bias, and the temperature distribution of the air blown out of the heat exchanger. Is made uniform.
[0018]
In addition, since the control plate is brazed to a portion corresponding to the flat portion of the inner peripheral surface of the header tank, the brazing portion of the control plate is formed into a straight line that is easy to mold, and is securely brazed to the inner peripheral surface of the header tank. It becomes possible to attach.
[0019]
Further, since the flat portion between the guide surfaces of the upper wall portion of the header tank is located below the two guide surfaces, the vertical dimension of the portion corresponding to the flat portion of the header tank is relatively short. Further, since the control plate is disposed at a position where the vertical dimension of the header tank is short, the vertical size of the control plate is shortened, thereby reducing the material removal of the control plate and reducing the cost. Reduced.
[0020]
According to a fourth aspect of the present invention, in any one of the first to third aspects of the present invention, a plurality of tubes are arranged in the air flow direction, and a tank is provided inside the header tank corresponding to the plurality of tubes. A partition plate for partitioning the inside in the air flow direction is provided, and the header tank is configured so that the heat exchange medium flowing into the header tank flows sequentially through the plurality of tube groups. A flat portion extending in the tube juxtaposition direction is formed between the guide surfaces adjacent to each other in the direction, and the partition plate is brazed to a portion corresponding to the flat portion on the inner peripheral surface of the header tank.
[0021]
According to this configuration, for example, when the tube group is arranged in two rows, the inside of the header tank is partitioned into two spaces in the air flow direction by the partition plate. When the heat exchange medium flows into the space on the downstream side of the air flow inside the header tank, the heat exchange medium flows through the corresponding tube group, and then flows through the tube group on the upstream side in the air flow direction. Thereby, the surrounding air exchanges heat with the heat exchange medium by the two tube groups, so that the heat exchange efficiency is improved.
[0022]
Further, since the partition plate is brazed to a portion corresponding to the flat portion of the inner peripheral surface of the header tank, similar to the invention of claim 3, while the shape of the brazed portion of the partition plate is made straight for easy molding, It is possible to reliably braze the inner peripheral surface of the header tank.
[0023]
Furthermore, since the flat portion between the guide surfaces of the upper wall portion of the header tank is located below the two guide surfaces, the vertical dimension of the portion corresponding to the flat portion of the header tank becomes relatively short. Since the partition plate is provided at a position where the dimension in the vertical direction is short, the cost of the partition plate is reduced as in the third aspect of the present invention.
[0024]
According to a fifth aspect of the present invention, in the third or fourth aspect, the flat portion is located below the guide surface, and the condensed water flowing through the two guide surfaces is provided between adjacent guide surfaces of the header tank upper wall portion. Is formed by the guide surface and the flat portion so as to guide the gas to the outside of the header tank upper wall portion.
[0025]
According to this configuration, since the condensed water flowing on the guide surface is discharged from the upper wall of the header tank by the discharge groove, even when the amount of generated condensed water is large, the condensed water does not stay at the periphery of the tube insertion hole, Thereby, irrespective of the amount of condensed water generated, corrosion at the joint between the peripheral edge of the tube insertion hole and the outer peripheral surface of the tube is reliably prevented.
[0026]
According to a sixth aspect of the present invention, in any one of the first to fifth aspects of the present invention, the header tank is configured by a combination of an upper member and a lower member that are vertically divided.
[0027]
According to this configuration, the component of the header tank, which has a plurality of tube insertion holes and a guide surface and is complicated to form, is divided into an upper member and a lower member, each of which is a press-formed product of a plate material. Therefore, it is easy to form the constituent members of the header tank.
[0028]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
[0029]
FIG. 2 shows a heat exchanger according to an embodiment of the present invention. In this example, a case where the heat exchanger is an evaporator 1 which constitutes one element of a refrigeration cycle of a vehicle air conditioner will be described. The evaporator 1 is housed in a case (not shown) provided in a vehicle compartment, and is configured as a cooling heat exchanger for cooling air blown from a blower (not shown). ing.
[0030]
As shown in FIG. 3, the evaporator 1 includes a core 5 having a plurality of vertically extending tubes 2a, 3a and fins 4 arranged alternately in the vehicle width direction. An upper header tank 8 and a lower header tank 9 are provided respectively. Further, the evaporator 1 is arranged in the case such that air from the blower passes through the core 5 from the front to the rear of the vehicle body. The direction of air flow is indicated by a white arrow A in FIGS. 1, 4 and 5.
[0031]
Each of the tubes 2a and 3a of the core 5 is a flat tube formed by bending a thin plate made of an aluminum alloy so as to have a rectangular cross section that is long in the air flow direction. As shown in FIG. 4, the tube 2a is arranged on the upstream side in the air flow direction, and the tube 2a constitutes an upstream tube group 2, while the tube 3a is arranged on the downstream side, and the tube 3a is arranged on the downstream side. Group 3 is constituted.
[0032]
Each fin 4 is a corrugated fin formed by corrugating a thin plate made of an aluminum alloy into a corrugated shape. The fins 4 extend from the vicinity of the upper end to the vicinity of the lower end of the tubes 2a, 3a and extend from the upstream tube group 2 to the downstream tube group 3. It extends continuously. A brazing material is provided in a layer form on at least one surface of the plates constituting the tubes 2a, 3a and the fins 4, and the fins 4 are brazed to the side surfaces of the tubes 2a, 3a to form the core 5. As shown in FIG. 2, fins 4, 4 are disposed at both ends of the core 5 in the direction in which the tubes 2a, 3a and the fins 4 are juxtaposed. They are held by end plates 11, 11, respectively.
[0033]
On the other hand, the lower header tank 9 is formed in an elongated box shape extending over both ends of the core 5 in the direction in which the tubes 2a and 3a and the fins 4 are arranged, and has an upper member 12 and a lower member It is divided into thirteen. The upper member 12 is formed by press-forming an aluminum alloy plate material in which brazing materials are provided in layers on both surfaces so as to have a U-shaped cross section that opens downward, and includes a header tank upper wall portion 12a, It comprises a pair of side walls 12b, 12b extending substantially vertically downward from both edges in the air flow direction of the wall 12a.
[0034]
As shown in FIG. 1, bulges 14, 14,... Bulging upward are respectively formed at positions corresponding to the lower end of the upstream tube 2 a of the header tank upper wall 12 a, and these bulges 14 adjacent to each other are formed. , 14 are spaced from each other in the direction in which the tube 2a and the fin 4 are arranged. A first flat portion 16 extending substantially horizontally in the air flow direction is formed on the header tank upper wall portion 12a between the adjacent bulging portions 14,. Further, bulges 15, 15,... Similar to the bulges 14 are formed at locations corresponding to the lower end of the downstream tube 3a of the header tank upper wall 12a, and headers between the adjacent bulges 15, 15 are formed. A similar first flat portion 16 is formed on the tank upper wall portion 12a.
[0035]
The bulging portions 14 and 15 adjacent to each other in the air flow direction are also arranged at an interval from each other, and the header tank upper wall portion 12a between the adjacent bulging portions 14 and 15 is provided substantially horizontally with the tubes 2a and 3a. And a second flat portion 17 extending in the direction in which the fins 4 are arranged.
[0036]
Each of the bulging portions 14 and 15 is formed in the shape of a mountain having the highest bulging height in the central portion in the direction in which the tubes 2a and 3a and the fins 4 are arranged and in the central portion in the air flow direction. Tube insertion holes 14a and 15a for inserting and holding the lower ends of the tubes 2a and 3a are formed at the center of the bulging portions 14 and 15 in the direction in which the tubes 2a and 3a and the fins 4 are arranged. The slits 14a and 15a are formed on the outer surfaces of the bulging portions 14 and 15 in a slit shape extending in the vicinity of both ends in the air flow direction. That is, the outer surfaces of the bulging portions 14 and 15 extend downward from the peripheral edges of the tube insertion holes 14a and 15a toward the outside of the tube insertion holes 14a and 15a. The edge is continuous with the first flat portion 16 and the second flat portion 17.
[0037]
The ends of the tubes 2a, 3a of the core 5 are inserted into the tube insertion holes 14a, 15a, and the outer edges of the tube insertion holes 14a, 15a and the outer peripheral surfaces of the tubes 2a, 3a are brazed, respectively. I have.
[0038]
The condensed water generated in the core 5 when the surrounding air is cooled by the evaporator 1 flows along the tubes 2a, 3a and flows down to the periphery of the tube insertion holes 14a, 15a, from which the outer surfaces of the bulging portions 14, 15 are formed. The guide surfaces 14b, 15b guide the outside of the tube insertion holes 14a, 15a.
[0039]
Further, the condensed water flowing on the guide surfaces 14b and 15b flows toward the first flat portion 16 and the second flat portion 17. The first flat surface is formed by the guide surfaces 14b, 14b and 15b, 15b adjacent in the direction in which the tubes 2a, 3a and the fins 4 are juxtaposed, and the first flat portion 16 between the two guide surfaces 14b, 14b, 15b, 15b. A first discharge groove 20 for discharging the condensed water flowing into the portion 16 from the header tank upper wall portion 12a to the outside is formed. In addition, the guide surfaces 14b, 15b adjacent in the air flow direction and the second flat portion 17 between the two guide surfaces 14b, 15b allow the condensed water flowing in the second flat portion 17 to transfer the condensed water to the header tank upper wall portion 12a. A second discharge groove 21 for discharging from the outside to the outside is formed.
[0040]
On the other hand, the lower member 13 of the lower header tank 9 is formed by press-forming an aluminum alloy plate material in which brazing materials are provided in layers on both surfaces so as to have a U-shaped cross section opened upward. It comprises a lower wall portion 13a and a pair of side wall portions 13b, 13b extending substantially vertically upward from both edges in the air flow direction of the lower wall portion 13a. Similarly to the header tank upper wall portion 12a, bulging portions 23 and 24 bulging downward are formed on the lower portion 13a of the header tank at intervals.
[0041]
The pair of side walls 13b, 13b of the lower member 13 are arranged so as to fit between the side walls 12b, 12b of the upper member 12, and the lower side between the side walls 12b, 12b of the upper member 12. When the two side walls 13b, 13b of the member 13 are fitted together and the two members 12, 13 are combined, a cylindrical shape having a rectangular cross section with both ends opened in the longitudinal direction is formed, and both ends are opened at the lower end extension portions of the end plates 11, 11. A lower header tank 9 closed by 11a and having an internal space R is configured.
[0042]
Inside the lower header tank 9, as shown in FIGS. 1 and 5, an internal space R is defined by an upstream space R1 and a downstream space R1 corresponding to the upstream tube group 2 and the downstream tube group 3, respectively. A partition plate 25 for partitioning into the space R2 is provided.
[0043]
The partition plate 25 is arranged at a position corresponding to the second flat portion 17 of the lower header tank 9, and is formed in a rectangular shape extending over both ends of the header tank 9 in the direction in which the tubes 2 a and 3 a and the fins 4 are arranged. The vertical dimension of the partition plate 25 is set such that the upper edge and the lower edge of the partition plate 25 are in contact with the portion corresponding to the second flat portion 17 on the inner peripheral surface of the header tank 9. It is brazed to the inner peripheral surface of the header tank 9.
[0044]
As shown in FIG. 3, an inflow pipe 26 for flowing a heat exchange medium into the downstream space R2 is connected to the downstream space R2 of the lower header tank 9. The downstream end of the inflow pipe 26 passes through the lower end extension 11a of the left end plate 11, and is fixed to the lower end extension 11a. The heat exchange medium from the inflow pipe 26 flows toward the right end of the downstream space R2, and flows into each of the tubes 3a of the downstream tube group 3 on the way.
[0045]
A control plate 28 that controls the flow of the heat exchange medium that has flowed in is arranged at the left and right intermediate portion of the downstream space R2. The control plate 28 is formed in a rectangular shape extending over both ends of the downstream space R2 in the air flow direction, and has a through hole 28a formed in the center thereof, and a part of the heat exchange medium passes through the through hole 28a. The heat exchange medium flowing through the tubes 3a before and after the control plate 28 is made uniform by passing the heat exchange medium, and the unevenness of the bulges 24 and 15 of the lower wall 13 and the upper wall 12 of the header tank 9 causes the heat exchange medium to flow. By controlling the flow rate, the heat exchange medium flows from the left tube 3a to the right tube 3a without bias.
[0046]
The upper and lower dimensions of the control plate 28 are set such that the upper edge and the lower edge of the control plate 28 are in contact with the portion corresponding to the first flat portion 16 on the inner peripheral surface of the header tank 9. 9 to be brazed to the inner peripheral surface. Note that a plurality of the control plates 28 may be provided.
[0047]
On the other hand, as shown in FIG. 5, an outflow pipe 29 for flowing out the heat exchange medium inside the evaporator 1 to the outside is connected to the upstream space R1 of the lower header tank 9. The upstream end of the outflow pipe 29 penetrates through the lower end extension 11a of the end plate 11 similarly to the inflow pipe 26, and is fixed to the lower end extension 11a.
[0048]
As shown in FIG. 2, the upper header tank 8 has a vertically symmetric shape with the lower header tank 9, and is composed of a combination of an upper member 31 and a lower member 32. That is, a plurality of bulges 33, 33,... Are formed at intervals on the lower wall of the header tank of the lower member 32, and a tube insertion hole is opened on the outer surface of each bulge 33. When the side walls of the upper member 31 are fitted between the side walls of the lower member 32, the end members 11, 11 b have a cylindrical shape with both ends opened. To form an upper header tank 8 having an internal space R.
[0049]
In the evaporator 1 configured as described above, the heat exchange medium flowing into the downstream space R2 of the lower header tank 9 from the inflow pipe 26 via an expansion valve (not shown) is supplied to each tube of the downstream tube group 3. 3a, flows upward through the tubes 3a, and flows into the internal space R of the upper header tank 8. The heat exchange medium that has flowed into the upper header tank 8 flows into each tube 2a of the upstream tube group 2, flows downward through each tube 2a, and flows into the upstream space R1 of the lower header tank 9; It flows out from the outflow pipe 29 to the outside.
[0050]
As described above, when the heat exchange medium flowing inside the evaporator 1 and the surrounding air exchange heat to cool the air, condensed water is generated in the core 5 and travels down the tubes 2a and 3a to form the lower header tank. 9 flows down to the periphery of the tube insertion holes 14a and 15a. At this time, swelling portions 14 and 15 swelling upward corresponding to the lower ends of the tubes 2a and 3a are formed in the header tank upper wall portion 12a, and the tube insertion holes are opened to the outer surfaces of the swelling portions 14 and 15. 14a, 15a are formed, and condensed water around the periphery of the tube insertion holes 14a, 15a is guided to the outside of the tube insertion holes 14a, 15a by the guide surfaces 14b, 15b on the outer surfaces of the swelling portions 14, 15; Water does not stay at the peripheral edges of the tube insertion holes 14a and 15a, so that corrosion at the joint between the peripheral edges of the tube insertion holes 14a and 15a and the outer peripheral surfaces of the tubes 2a and 3a can be prevented, and the durability of the evaporator 1 is sufficiently improved Obtainable.
[0051]
The condensed water guided to the outside of the tube insertion holes 14a and 15a by the guide surfaces 14b and 15b flows to the first flat portion 16 and the second flat portion 17 continuous with the guide surfaces 14b and 15b, and the first discharge groove. The air is discharged to the outside of the header tank upper wall 12a through the second discharge groove 21 and the second discharge groove 21. Thereby, even when the amount of condensed water generated is large depending on the operation state of the refrigeration cycle, the condensed water can be discharged to the outside of the header tank upper wall portion 12a, so that the periphery of the tube insertion holes 14a, 15a and the tubes 2a, 3a. Corrosion at the joint with the outer peripheral surface can be more reliably prevented.
[0052]
Further, since the control plate 28 for controlling the flow of the heat exchange medium is disposed in the downstream space R2 of the lower header tank 9, the heat exchange medium flowing from the inflow pipe 26 is supplied to each tube 3a of the downstream tube group 3. And the temperature distribution of the air flowing out from the evaporator 1 can be made uniform. Since the control plate 28 is brazed to the location corresponding to the first flat portion 16 on the inner peripheral surface of the header tank 9, the upper edge of the control plate 28 is formed into a straight line extending substantially parallel to the first flat portion 16. Brazing to the inner peripheral surface of the header tank 9 can be reliably performed only by forming, and the control plate 28 can be easily formed.
[0053]
Further, the first flat portion 16 of the header tank upper wall portion 12a is located below the bulging portions 14 and 15, and the vertical dimension of a portion corresponding to the first flat portion 16 of the header tank 9 is relatively large. short. In this embodiment, as described above, the control plate 28 is disposed at a position corresponding to the first flat portion 16 of the header tank 9 having a short vertical dimension, so that the vertical dimension of the control plate 28 is reduced. As a result, material removal can be reduced, and costs can be reduced.
[0054]
Further, the lower header tank 9 is divided into two by the partition plate 25, and the heat exchange medium is caused to flow through the downstream tube group 3 and the upstream tube group 2 in order. , 3 allow heat exchange with the heat exchange medium, thereby increasing the heat exchange efficiency. Further, since the partition plate 25 is disposed at a position corresponding to the second flat portion 17 on the inner peripheral surface of the header tank 9, the formation of the partition plate 25 is facilitated while facilitating the formation of the partition plate 25 as in the case of the control plate 28 described above. The attachment can be performed reliably, and the cost can be reduced by reducing material removal.
[0055]
Further, since the guide surfaces 14b and 15b are formed by the outer surfaces of the plurality of bulging portions 14 and 15 formed on the upper wall portion 12a of the lower header tank 9, the rigidity of the upper member 12 can be sufficiently increased without increasing the plate thickness. Thus, the header tank 9 which is lightweight and has high pressure resistance can be obtained. In addition, since the swelling portions 14, 15, 23, 24 are respectively formed on the upper wall portion 12a and the lower wall portion 13a of the lower header tank 9, the swelling height of each of the swelling portions 14, 15, 23, 24 is adjusted. By the shape, the flow of the heat exchange medium flowing from the inflow pipe 26 can be controlled similarly to the control plate 28. Thus, the control plate 28 can be omitted, and the amount of heat exchange medium flowing into each tube 3a of the downstream tube group 3 can be easily made uniform.
[0056]
Furthermore, since each of the header tanks 8, 9 is composed of a combination of the upper members 31, 12, and the lower members 32, 13, the plurality of tube insertion holes 14a, 15a and the bulging portions 14, 15, 23, 24 are provided. The constituent members of the header tanks 8 and 9 having the above can be easily formed.
[0057]
In the above-described embodiment, the first flat portion 16 of the upper wall portion 12a of the lower header tank 9 is formed to be substantially horizontal. However, the present invention is not limited to this. 16 may be formed in an inclined surface shape such that the center portion of the header tank upper wall portion 12a in the air flow direction is located at the uppermost position, and the lower portion is located therefrom toward the outside of the header tank upper wall portion 12a. In this case, the condensed water flowing from the guide surfaces 14b and 15b to the first flat portion 16 can be more smoothly discharged to the outside of the header tank upper wall portion 12a.
[0058]
In the embodiment, each of the upstream tube group 2 and the downstream tube group 3 is one path. However, the present invention is not limited to this. For example, the through-hole 28a of the control plate 28 may be omitted and the downstream tube group may be omitted. 3 may be divided into two paths.
[0059]
In the above embodiment, the case where the present invention is applied to the evaporator 1 having the two rows of tube groups 2 and 3 has been described. However, the present invention is directed to an evaporator having one row of tube groups and an evaporator having three or more rows. It is also possible to apply to vessels.
[0060]
Further, the present invention is applicable to a heat exchanger for cooling air other than the evaporator 1 of the vehicle air conditioner.
[0061]
【The invention's effect】
As described above, according to the heat exchanger according to the first aspect of the present invention, the heat exchanger extends downward from the peripheral edge of each tube insertion hole toward the outside of the header tank upper wall, and falls along the tubes during air cooling. Since the guide surface for guiding condensed water to the outside from the periphery of the tube insertion hole is formed, the condensed water is discharged from the periphery of the tube insertion hole without remaining at the periphery thereof, and thereby, the joint between the periphery of the tube insertion hole and the outer periphery of the tube is formed. Can be prevented, and the durability of the heat exchanger can be increased.
[0062]
According to the second aspect of the present invention, since each tube insertion hole forming portion of the header tank upper wall portion is bulged and the guide surface is formed by the bulging portion outer surface, the thickness of the constituent members of the header tank can be increased. Therefore, sufficient pressure resistance can be obtained, and the weight of the heat exchanger can be reduced. When the heat exchange medium is allowed to flow from one end side of the header tank in the direction in which the tubes are arranged, the heat exchange medium is allowed to flow evenly into each tube by setting the swelling height of the swelling portion. Thus, the temperature distribution of the air blown out of the heat exchanger can be easily made uniform.
[0063]
According to the third aspect of the present invention, the heat exchange medium inflow pipe is connected to one longitudinal end of the header tank, and the control plate for controlling the flow of the heat exchange medium is disposed inside the header tank. Can flow into each tube without bias, and the temperature distribution of the air blown out from the heat exchanger can be made uniform. In addition, a flat portion was formed on the upper wall of the header tank, and the control plate was brazed to a portion corresponding to the flat portion of the inner peripheral surface of the header tank. Brazing can be surely performed, and a small amount of material is required for the control plate, so that the cost can be reduced.
[0064]
According to the invention as set forth in claim 4, the tube group is arranged in a plurality of rows, the partition plate for partitioning the internal space corresponding to the tube group is arranged inside the header tank, and the heat exchange medium is sequentially passed through the plurality of tube groups. With this arrangement, the surrounding air passes through the plurality of tube groups and exchanges heat with the heat exchange medium, thereby increasing the heat exchange efficiency. In addition, since the partition plate is brazed to the portion corresponding to the flat portion of the inner peripheral surface of the header tank, the partition plate can be securely brazed to the inner surface of the header tank while the partition plate is easily formed in the same manner as in the invention of claim 3. At the same time, the cost of the partition plate can be reduced.
[0065]
According to the fifth aspect of the present invention, since the discharge groove for guiding condensed water to the outside of the header tank upper wall portion is formed between the guide surfaces of the header tank upper wall portion, the periphery of the tube insertion hole regardless of the amount of condensed water generated. Corrosion of the joint between the tube and the outer peripheral surface of the tube can be reliably prevented.
[0066]
According to the sixth aspect of the present invention, since the header tank is made of a combination of the upper member and the lower member, it is possible to easily form the members constituting the header tank.
[Brief description of the drawings]
FIG. 1 is a perspective view showing a part of a lower header tank.
FIG. 2 is a view of the evaporator according to the embodiment of the present invention as viewed from a downstream side in an air flow direction.
FIG. 3 is an enlarged longitudinal sectional view showing the internal structure of the lower header tank on the downstream side in the air flow direction.
4A is a cross-sectional view taken along line AA of FIG. 2, and FIG. 4B is a cross-sectional view taken along line BB of FIG.
FIG. 5 is a plan view of the left side of the upper member of the lower header tank.
FIG. 6 is a diagram corresponding to FIG. 4A according to a modification.
[Explanation of symbols]
1 Evaporator (heat exchanger)
2,3 tube group
2a, 3a tube
9 Lower header tank
12 Upper member
12a Header tank upper wall
13 Lower member
14, 15 bulge
14a, 15a Tube insertion hole
14b, 15b Guide surface
16 1st flat part
17 2nd flat part
20 First discharge groove
21 Second discharge groove
25 Partition plate
26 Inflow pipe
28 Control board
R interior space

Claims (6)

A tube group in which a plurality of vertically extending tubes are juxtaposed in a direction intersecting with the air flow direction, and a tube end portion is inserted and held in a tube insertion hole formed in a lower end of the tube group and formed in an upper wall portion. A heat exchanger that is configured to cool the air by exchanging heat with a surrounding air and a heat exchange medium flowing through each tube. hand,
The header tank upper wall portion extends downward from the periphery of each tube insertion hole toward the outside of the tube insertion hole, and guides condensed water falling along the tube during cooling of the air to the outside from the periphery of the tube insertion hole. A heat exchanger having a guide surface. In claim 1,
A heat exchanger wherein each tube insertion hole forming portion of a header tank upper wall portion bulges upward, and a guide surface is formed by an outer surface of the bulge portion. In claim 1 or 2,
The header tank extends in the direction in which the tubes are arranged, and an inflow pipe through which a heat exchange medium flows into the header tank is connected to one end in the longitudinal direction of the header tank,
Inside the header tank, a control plate for controlling the flow of the heat exchange medium flowing from the inflow pipe and flowing inside the tank is provided,
A flat portion extending in the air flow direction is formed between guide surfaces adjacent to the header tank upper wall in the tube juxtaposition direction,
The heat exchanger, wherein the control plate is brazed to a portion corresponding to a flat portion on the inner peripheral surface of the header tank. In any one of claims 1 to 3,
The tube group is arranged in a plurality of rows in the air flow direction.In the header tank, a partition plate that partitions the inside of the tank in the air flow direction is arranged corresponding to the plurality of rows of the tube groups, and the header tank flows in. The heat exchange medium is configured to sequentially flow through the plurality of tube groups,
A flat portion extending in the tube juxtaposition direction is formed between guide surfaces adjacent to the header tank upper wall portion in the air flow direction,
The heat exchanger, wherein the partition plate is brazed to a portion corresponding to a flat portion on the inner peripheral surface of the header tank. In claim 3 or 4,
The flat part is located below the guide surface,
A discharge groove for guiding condensed water flowing through both guide surfaces to the outside of the header tank upper wall portion is formed between the adjacent guide surfaces of the header tank upper wall portion by the guide surface and the flat portion. Heat exchanger. In any one of claims 1 to 5,
The heat exchanger is characterized in that the header tank is composed of a combination of an upper member and a lower member that are vertically divided.

Images