Title:
Heat exchanger and manufacture method for the same
Kind Code:
A1


Abstract:
A heat exchanger and a manufacture method thereof are provided. Before a tank body and a core plate of a header tank of the heat exchanger are fastened to each other, a gel seal material or a liquid seal material is applied to at least one of a seal surface of the core plate and that of the tank body and hardened. Thus, a seal member which adheres to the seal surface due to the tackiness of the seal member is formed. The core plate and the tank body are fastened to each other in such a state that the part between the seal surface of the core plate and that of the tank body are sealed by the seal member having been hardened. Accordingly, the seal member can be restricted of twisting and position-deviating when the core plate and the tank body are fastened to each other.



Inventors:
Hakamata, Osamu (Kariya-city, JP)
Ozaki, Tatsuo (Okazaki-city, JP)
Ninagawa, Toshihide (Yatomi-city, JP)
Application Number:
11/895820
Publication Date:
03/06/2008
Filing Date:
08/28/2007
Assignee:
DENSO Corporation (Kariya-city, JP)
Primary Class:
Other Classes:
29/890.03
International Classes:
F28F9/02; B21D53/02
View Patent Images:



Primary Examiner:
HIGGINS, JOHN D
Attorney, Agent or Firm:
HARNESS DICKEY (TROY) (Troy, MI, US)
Claims:
What is claimed is:

1. A manufacture method for a heat exchanger, the heat exchanger having a plurality of tubes in which a fluid flows and a fin which is joined to an outer surface of the tube to improve a heat exchange and a header tank which is arranged at one end of a longitudinal direction of the tube and communicated with the tubes, the header tank including a core plate and a tank body which define therebetween at least one inner space, the core plate being joined to the tubes, the manufacture method comprising: applying one of a liquid seal material and a gel seal material to at least one of a seal surface of the core plate and a seal surface of the tank body; hardening the seal material to form a seal member which adheres to the seal surface due to tackiness of the seal member; and fastening the core plate and the tank body to each other, in such a state that the seal member having been hardened is resiliently deformed to seal a part between the seal surface of the core plate and the seal surface of the tank body which are opposite to each other.

2. The manufacture method according to claim 1, wherein: the tank body and the core plate define therebetween a plurality of the inner spaces which are partitioned from each other by at least one partition wall; and the applying is performed to apply the one of the gel seal material and the liquid seal material to the at least one of the seal surface of the core plate and that of the tank body, in such a manner that each of the plurality of the inner spaces is surrounded by the seal material.

3. The manufacture method according to claim 1, wherein after the applying of the seal material to the seal surface, the hardening of the seal material is performed.

4. The manufacture method according to claim 1, wherein the applying of the seal material to the seal surface is performed simultaneously with the hardening of the seal material.

5. The manufacture method according to claim 1, wherein the seal material is applied to the one of the seal surface of the core plate and that of the tank body, in such a manner that a cross section of the seal member has a shape convex toward the other of the seal surface of the core plate and that of the tank body.

6. The manufacture method according to claim 5, wherein the seal material is applied to the seal surface such that the seal member having the cross section with a substantially semicircle shape is formed.

7. The manufacture method according to claim 1, wherein the applying of the seal material to the seal surface is performed after the tube, the fin and the core plate are assembled.

8. The manufacture method according to claim 1, wherein the applying of the seal material to the seal surface is performed before the tube, the fin and the core plate are assembled.

9. The manufacture method according to claim 1, wherein the tank body and the core plate are fastened to each other by swaging.

10. The manufacture method according to claim 1, wherein a nail portion of the core plate is swaged with respect to the tank body so that the tank body and the core plate are fastened with each other.

11. The manufacture method according to claim 10, wherein the applying is performed in such a manner that the seal member has at least one lap portion where an applying start position and an applying finishing position of the seal material are overlapped with each other.

12. The manufacture method according to claim 11, wherein the applying of the seal material is performed such that the lap portion is positioned at a straight portion of the seal surface of the tank body, the straight portion extending substantially linearly.

13. The manufacture method according to claim 11, wherein the nail portion is swaged to overlap the lap portion.

14. The manufacture method according to claim 1, further comprising joining the tubes to the core plate by brazing, wherein: the seal material is applied to the seal surface of the core plate after the joining; and the seal material is hardened in such a state that the seal material contains therein flux residue which adheres to the seal surface due to the brazing.

15. The manufacture method according to claim 1, wherein a protrusion of the seal surface of the tank body is pressed against the seal member which has been applied to the seal surface of the core plate and hardened, so that the seal member is resiliently deformed to seal the part between the seal surface of the core plate and the seal surface of the tank body.

16. The manufacture method according to claim 15, wherein the protrusion of the seal surface of the tank body having a cross section with a substantially semicircular shape.

17. The manufacture method according to claim 1, wherein the seal material is hardened by an irradiation of ultraviolet light.

18. The manufacture method according to claim 1, wherein the seal material is hardened by heating.

19. The manufacture method according to claim 1, wherein the applying is performed to apply the seal material to a groove portion which is formed at the seal surface of the core plate.

20. The manufacture method according to claim 1, wherein the seal material is applied to the seal surface of the tank body where projections and depressions are formed, in such a manner that the projections and depressions are filled by the seal material.

21. The manufacture method according to claim 1, wherein the applying is performed to apply the seal material to a groove portion which is formed at the seal surface of the tank body.

22. The manufacture method according to claim 21, wherein the groove portion having a cross section with a substantially semicircular shape.

23. A heat exchanger, comprising: a plurality of tubes in which a fluid flows; a fin which is joined to an outer surface of the tube to improve a heat exchange; a header tank which is arranged at one end of a longitudinal direction of the tube and communicated with the tubes, the header tank including a core plate and a tank body which define therebetween at least one inner space, the core plate being joined to the tubes; and a seal member which is arranged between a seal surface of the core plate and a seal surface of the tank body to restrict the fluid leaking, wherein: the seal member is formed by hardening one of a gel seal material and a liquid seal which is applied to at least one of the seal surface of the core plate and the seal surface of the tank body, to adhere to the seal surface due to tackiness of the seal member; and the seal member seals a part between the seal surface of the core plate and the seal surface of the tank body in such a state that the seal member is resiliently deformed.

24. The heat exchanger according to claim 23, wherein the tank body has therein at least one partition wall by which a plurality of the inner spaces are partitioned from each other; and each of the plurality of the inner spaces is surrounded by the seal member.

25. The heat exchanger according to claim 23, wherein the seal member which is positioned at the one of the seal surface of the core plate and the seal surface of the tank body has a cross section with a shape convex toward the other of the seal surface of the core plate and that of the tank body.

26. The heat exchanger according to claim 25, wherein the cross section of the seal member has a substantially semicircle shape.

27. The heat exchanger according to claim 23, wherein the core plate has a nail portion which protrudes thereout and is swaged so that the tank body and the core plate are fastened to each other.

28. The heat exchanger according to claim 23, wherein: the seal member is formed by hardening the one of the gel seal material and the liquid seal which is applied to the seal surface of the core plate; the seal surface of the tank body has a protrusion; and the core plate and the tank body are fastened to each other in such a state that the seal member is resiliently deformed by the protrusion to seal the part between the seal surface of the core plate and that of the tank body.

29. The heat exchanger according to claim 28, wherein the protrusion has a cross section with a substantially semicircular shape.

30. The heat exchanger according to claim 23, wherein the seal surface of the core plate has a groove portion which is filled by the seal member.

31. The heat exchanger according to claim 23, wherein the seal member is formed by applying the one of the liquid seal material and the gel seal material and simultaneously hardening the seal material.

32. The heat exchanger according to claim 23, wherein the seal member is formed by applying the one of the liquid seal material and the gel seal material and thereafter hardening the seal material.

33. The heat exchanger according to claim 23, wherein the seal surface of the tank body has projections and depressions which are filled by the seal member.

34. The heat exchanger according to claim 23, wherein the seal surface of the tank body has a groove portion, which is filled by the seal member.

35. The heat exchanger according to claim 34, wherein the groove portion has a cross section with a substantially semicircular shape.

36. The heat exchanger according to claim 23, wherein the core plate and the tank body are fastened to each other by swaging.

37. The heat exchanger according to claim 27, wherein the seal member has at least one lap portion where an applying start position and an applying finishing position of the seal material are overlapped with each other.

38. The heat exchanger according to claim 37, wherein the lap portion is positioned at a straight portion of the seal surface of the tank body, the straight portion extending substantially linearly.

39. The heat exchanger according to claim 37, wherein the nail portion is swaged to overlap the lap portion.

Description:

CROSS REFERENCE TO RELATED APPLICATION

This application is based on a Japanese Patent Application No. 2006-235022 filed on Aug. 31, 2006, and a Japanese Patent Application No. 2006-235024 filed on Aug. 31, 2006, the disclosures of which are incorporated herein by reference.

FIELD OF THE INVENTION

The present invention relates to a heat exchanger and a manufacture method thereof.

BACKGROUND OF THE INVENTION

Generally, for example, with reference to JP-3-138116A, a heat exchanger has multiple tubes in which fluid flows, heat-exchanging fins joined to the outer surfaces of the tubes, a first header tank which is communicated with the tubes to shunt the fluid to the multiple tubes, and a second header tank which is communicated with the tubes to collect the fluid from the tubes.

In this case, each of the first header tank and the second tank includes a core plate to which the tubes are joined, a tank body which defines therein a tank inner space together with the core plate, and a packing member which is constructed of a resilient material such as a rubber to seal the part between the core plate and the tank body.

According to JP-3-138116A, in the manufacture process of the first and second header tanks, the core plate, the tank body and the packing member are separately prepared. The core plate and the tank body are fastened in such a manner that the packing member is sandwiched between the seal surface of the core plate and that of the tank body. Thus, the part between the seal surface of the tank body and the seal surface of the core plate is sealed by the packing member, to restrict the fluid from leaking from the tank inner space.

In this case, because the packing member is constructed of the resilient material such as the rubber, the packing member may be twisted or position-deviated when the core plate and the tank body are fastened. Thus, slight gap will occur between the seal surface of the tank body and that of the core plate, so that liquid leaks from the tank inner space.

SUMMARY OF THE INVENTION

In view of the above-described disadvantages, it is an object of the present invention to provide a heat exchanger and a manufacture method thereof to restrict a fluid in the heat exchanger from leaking.

According to a first aspect of the present invention, a manufacture method for a heat exchanger is provided. The heat exchanger has a plurality of tubes in which a fluid flows, a fin which is joined to an outer surface of the tube to improve a heat exchange, and a header tank which is arranged at one end of a longitudinal direction of the tube and communicated with the tubes. The header tank includes a core plate and a tank body which define therebetween at least one inner space. The core plate is joined to the tubes. The manufacture method includes applying one of a liquid seal material and a gel seal material to at least one of a seal surface of the core plate and a seal surface of the tank body which are opposite to each other, hardening the seal material to form a seal member which adheres to the seal surface due to tackiness of the seal member, and fastening the core plate with the tank body in such a state that the seal member having been hardened is resiliently deformed to seal a part between the seal surface of the core plate and the seal surface of the tank body.

Because the seal member tightly contacts the seal surface due to tackiness, the packing member constructed of the seal member can be restricted of twisting and position-deviating when the core plate and the tank body are fastened to each other. Therefore, the slight gap between the seal surface of the core plate and that of the tank body can be restricted so that the liquid leakage can be reduced.

According to a second aspect of the present invention, a heat exchanger includes a plurality of tubes in which a fluid flows, a fin which is joined to an outer surface of the tube to improve a heat exchange, a header tank which is arranged at one end of a longitudinal direction of the tube and communicated with the tubes, and a seal member. The header tank includes a core plate and a tank body which define therebetween at least one inner space. The core plate is joined to the tubes. The seal member is arranged between a seal surface of the core plate and a seal surface of the tank body to restrict the fluid leaking. The seal member is formed by hardening one of a liquid seal material and a gel seal material which is applied to at least one of the seal surface of the core plate and the seal surface of the tank body, to adhere to the seal surface due to tackiness of the seal member. The seal member seals a part between the seal surface of the core plate and the seal surface of the tank body, in such a manner that the seal member is resiliently deformed.

In this case, because the seal member tightly contacts the seal surface due to tackiness, the seal member can be restricted of twisting and position-deviating when the core plate and the tank body are fastened to each other. Therefore, the slight gap between the seal surface of the core plate and that of the tank body can be restricted so that the liquid leakage can be reduced.

BRIEF DESCRIPTION OF THE DRAWINGS

Other objects, features and advantages of the present invention will become more apparent from the following detailed description made with reference to the accompanying drawings, in which:

FIG. 1 is a schematic view showing a heat exchanger according to a first embodiment of the present disclosure;

FIG. 2 is a schematic sectional view taken along the line II-II in FIG. 1 according to the first embodiment;

FIG. 3 is an enlarged sectional view of the part III in FIG. 2;

FIG. 4 is an enlarged sectional view of the part IV in FIG. 1 according to the first embodiment;

FIG. 5 is a schematic view showing the heat exchanger where a tank body is disassembled according to the first embodiment;

FIGS. 6A, 6B, 6C and 6D respectively show a seal material applying process, a hardening process, a pressing process and a fastening process when a header tank is assembled according to the first embodiment;

FIG. 7 is a schematic view showing an applying method of a seal material of FIG. 2;

FIG. 8 is a schematic view showing a seal surface of a core plate according to the first embodiment;

FIG. 9 is an enlarged view showing the part IX in FIG. 8;

FIG. 10 is a schematic view showing a heat exchanger according to a second embodiment of the present disclosure;

FIG. 11 is a schematic view showing a seal surface of a core plate according to the second embodiment;

FIG. 12 is a cross sectional view taken along the line XII-XII in FIG. 11;

FIG. 13 is a schematic sectional view showing a core plate according to a third embodiment of the present disclosure;

FIG. 14 is a schematic sectional view which is taken along the line II-II in FIG. 1 and shows a heat exchanger according to a fourth embodiment of the present disclosure;

FIG. 15 is an enlarged sectional view of the part IV in FIG. 1 according to the fourth embodiment;

FIGS. 16A, 16B, 16C and 16D respectively show a seal material applying process, a hardening process, a pressing process and a fastening process when a header tank is assembled according to the fourth embodiment;

FIG. 17 is schematic view showing a seal surface of the header tank according to the fourth embodiment;

FIG. 18 is an enlarged sectional view of the part XVIII in FIG. 17 according to the fourth embodiment;

FIG. 19 is a schematic sectional view showing a part of a tank body and a seal member according to a fifth embodiment of the present disclosure;

FIG. 20 is a schematic sectional view showing a part of a tank body and a seal member according to a sixth embodiment of the present disclosure; and

FIG. 21 is schematic view showing a seal surface of a header tank according to a seventh embodiment of the present disclosure.

DETAILED DESCRIPTION OF THE EXAMPLED EMBODIMENTS

First Embodiment

A heat exchanger according to a first embodiment of the present invention will be described with reference to FIGS. 1-9. The heat exchanger can be suitably used as a radiator 1 of a vehicle, for example. The radiator 1 can be arranged in an engine cabin of the vehicle, to cool fluid (e.g., cooling water) by air blown by a blower.

As shown in FIG. 1, the radiator 1 is provided with a core unit 4 which includes multiple tubes 2 and multiple fins 3, two side plates 4a, 4b and two header tanks 5a and 5b.

The tube 2 is constructed of a flat pipe in which cooling water from the engine flows. The tube 2 can be made of a light metal having a high heat conductivity, for example, aluminum. In this embodiment, the tube 2 is constructed of a clad material which surface (facade surface or/and back surface) is covered by a filler material.

The fin 3 is joined to the outer surface of the tube 2 to increase the area of the heat transferring of the tube 2 with air for cooling, so that the heat exchange between air and cooling water is improved. In this embodiment, the fin 3 is constructed of a corrugated fin which has a wave shape (by roller-shaping or the like) when being viewed in a flowing direction of air for cooling. The core unit 4 for cooling engine cooling water or the like can be provided with a substantial rectangular shape, for example.

The side plates 4a and 4b are respectively arranged at two end portions of the core unit 4 and extend in a longitudinal direction of the tube 2, to reinforce the core unit 4. The side plates 4a and 4b can be made of a light metal, for example, aluminum.

The header tanks 5a and 5b are respectively arranged at the two end portions of the longitudinal direction of the tube 2 and extend in a direction which is substantially perpendicular to the longitudinal direction of the tube 2, to be communicated with each of the tubes 2. In this embodiment, the header tank 5a can distribute cooling water (which has a high temperature and has flowed from the engine) to the multiple tubes 2. The header tank 5b can retrieve cooling water having been cooled (that is, having been heat-exchanged) at the core unit 4 through the multiple tubes 2, so that cooling water returns to the engine.

In this case, an intake pipe 6a is connected with an cooling-water outflowing side of the engine. An outtake pipe 6b is connected with a cooling-water inflowing side of the engine.

The header tanks 5a and 5b have a substantially same construction (except for pipes 6a and 6b). Next, the construction of the header tank 5a will be described as an example.

As shown in FIG. 2, the header tank 5a has a core plate 50a and a tank body 50b through which an inner space 50c is defined in the header tank 5a.

The core plate 50a can be constructed of an alloy such as aluminum and has a substantially rectangular plate shape, for example. As shown FIG. 4, multiple through holes 56 are arranged at the core plate 50a. The tubes 2 and the side plates 4a and 4b are inserted through the through holes 56. In FIG. 4, the side plate 4b is omitted.

With reference to FIG. 5 showing a state where the tank body 50b is disassembled from the radiator 1, multiple nail portions 51a (for swaging) are arranged to surround the core plate 50a. The nail portions 51a are provided to fasten the core plate 50a to the tank body 50b.

In this case, as shown in FIG. 4, the nail portion 51a is bent to be provided with a bent portion. Thus, a groove portion 51b (bent portion) is formed at the inner sides (which face the tank body 50b) of the nail portions 51a. The groove portion 51b has a U-like shaped cross section, and an end portion 52 of the tank body 50b is inserted in the groove portion 51b. The groove portions 51b construct a ring shape along the periphery of the core plate 50a. In this embodiment, the bottom of the U-like shape of the groove portion 51b constructs a seal surface 51c (described later).

The core plate 50a can be constructed of a plate material clad by a filler material at the surface where the tubes 2 are inserted. The side plate 4a, 4b can be constructed of a plate material clad by a filler material at the surface where the tubes are joined.

The tank body 50b can be made of a resin material, and is formed to have a -like shaped cross section. That is, the tank body 50b has a concave shape to define therein a tank space 50c. As shown in FIGS. 2 and 4, the end portion 52 (rim portion) of the tank body 50b protrudes from the surface thereof outward, and has a ring shape to surround the opening of the tank body 50b.

The tip surface of the end portion 52 of the tank body 50b constructs a seal surface 53 (described later). As shown in FIG. 3, a protrusion 53a protrudes from the seal surface 53.

A seal member 54 is arranged between the seal surface 53 of the tank body 50b and the seal surface 51c of the core plate 50a. The seal member 54 can be deformed between the seal surface 53 and the groove portion 51b to seal the part between the end portion 52 of the tank body 50b and the core plate 51a so that cooling water can be restricted from leaking from the tank space 50c.

The seal member 54 can be constructed of a gel seal material or a liquid seal material which can be applied to the groove portion 51b and hardened. In this embodiment, an acrylic resin (which is hardened by ultraviolet light) or the like can be used as the seal material. It is desirable that the seal material is constructed of a resin which deterioration with respect to antifreeze is little. Alternatively, the seal member 54 can be also constructed of a thermosetting resin which can be hardened by heat.

Next, the manufacture method of the radiator 1 will be described.

At first, the multiple tubes 2, the core plates 50a, the fins 3 and the side plates 4a and 4b are prepared.

Next, the multiple tubes 2 are arrayed to be spaced from each other at a predetermined distance. The fins 3 are arranged so that the adjacent tubes 2 are separated from each other by the fin 3. Thus, the core unit 4 is temporarily assembled. Thereafter, the tubes 2 and the side plates 4a and 4b are inserted through the through holes 56 of the core plate 50a of the header tank 5a.

Next, the inner diameter of the one end (that is, the part which penetrates core plate 50a to be positioned in the part corresponding to tank space 50c) of the longitudinal direction of the tube 2 is enlarged, so that the tube 2 and the core plate 50a are fixed to each other.

Then, the tubes 2 and the side plates 4a and 4b are inserted through the through holes 56 of the core plate 50a of the header tank 5b. In this case, the inner diameter of the other end of the longitudinal direction of the tube 2 is enlarged, so that the tube 2 and the core plate 50a of the header tank 5b are fixed to each other.

Thus, the temporary assembly of the core plates 5oa of the header tanks 5a, 5b, the tubes 2, the fins 3 and the side plates 4a and 4b is provided. The assembly is held by a jig and heated in a furnace. Then, as shown in FIG. 5, the tubes 2, the fins 3, the side plates 4a and 4b and the core plates 5oa of the header tanks 5a, 5b are integrated with each other by brazing, for example.

Next, as shown in FIG. 6A, an applying process is performed. An injector 60 or the like in which a gel seal material (or liquid seal material) is filled is prepared, and then the seal material is provided through the injector 60 at the inner side (which is to face end portion 52 of tank body 50b) of the seal surface 51c of the core plate 50a of the header tank 5a. That is, the seal material is arranged at the upper side (shown in FIG. 6A) of the seal surface 51c.

The seal material is applied to the seal surface 51c in such a manner that the cross section of the seal member 54 has a convex shape (e.g., semicircle shape), as shown in FIG. 7. That is, the seal member 54 convexes to the opposite side of the seal surface 51c.

As shown in FIGS. 8 and 9, because the seal surface 51c of the core plate 50a has the ring shape as described above, the seal material is applied such that an applying start position 71 and an applying finish position 72 of the seal material are overlapped with each other at least at one lap portion 73.

In this case, as shown in FIG. 8, the lap portion 73 is arranged at a straight portion 80 (which straightly extends) of the seal surface 53. Moreover, the seal material of the seal member 54 from the injector 60 is also applied to the seal surface 51c of the core plate 50a of the side of the header tank 5b.

Thereafter, a hardening process is performed, as shown in FIG. 6B. The seal material having been applied to the seal surface 51c of the core plates 50a of the header tank 5a and the header tank 5b is irradiated with ultraviolet light, for example.

Next, as shown in FIG. 6C, the protrusion 53a of the seal surface 53 of the tank body 50b is pressed against the seal member 54 having been hardened, so that the seal member 54 is resiliently deformed. Accordingly, the seal surface 53 of the tank body 50b is tightly contacted with the seal member 54. In this state, the nail portions 51a are swaged so that the tank body 50b and the core plate 50a are fastened, as shown in FIG. 6D. That is, a fastening process has been performed. In this case, the core plate 50a is fastened with the tank body 50b, in such a state that the seal member 54 having been hardened is resiliently deformed to seal a part between the seal surface 51c of the core plate 50a and the seal surface 53 of the tank body 50b.

In this case, at least one of the nail portions 51a is arranged to overlap the lap portion 73. Thus, the manufacture of the header tank 5a is finished.

Similarly, the protrusion 53a of the seal surface 53 of the tank body 50b is pressed against the seal member 54 which has been applied to the seal surface 51c of the core plate 50a of the header tank 5b and hardened, so that the seal member 54 is resiliently deformed. Thus, the seal surface 53 of the tank body 50b is tightly contacted with the seal member 54. In this state, the nail portions 51a are swaged to fasten the tank body 50b to the core plate 50a.

In this case, at least one of the nail portions 51a is arranged to overlap the lap portion 73. Thus, the manufacture of the header tank 5b is finished.

In this embodiment, the gel seal material or the liquid seal material is applied to the seal surface 51c of the core plate 50a of the header tank 5a, 5b, and then the seal material is hardened by ultraviolet light or the like to construct the seal member 54. Thereafter, the core plate 50a and the tank body 50b are fastened.

In this case, the seal member 54 having been hardened has tackiness, to tightly contact the seal surface 51c of the core plate 50a due to the tackiness. Therefore, the seal member 54 can be restricted from twisting and position-deviating, when the core plate 50a and the tank body 50b are fastened. Thus, a gap between the seal surface 51c of the core plate 50a and the seal surface 53 of the tank body 50b is restricted from occurring, so that cooling water can be restricted from leaking.

In this case, because the seal member 54 has the tackiness, the seal material 54 can tightly contact the seal surface 51c and the seal surface 53 even when foreign matter such as rubbish is remained at the seal surface 51c of the core plate 50a and the seal surface 53 of the tank body 50b.

Moreover, in this embodiment, after the multiple tubes 2 are joined to the core plate 50a by brazing or the like, the gel seal material or the liquid seal material is applied to the seal surface 51c of the core plate 50a.

In this case, flux residue will adhere to the seal surface 51c of the core plate 50a after brazing. Thus, pits and projections are formed at the seal surface 51c due to the flux residue. Therefore, the seal material applied to the seal surface 51c are intertwined with the pits and projections, so that the seal member 54 can be restricted from leaving from the seal surface 51c of the core plate 50a. Furthermore, because the seal member 54 has been hardened in such a state that the seal material is intertwined with the flux residue, the cooling water can be restricted from leaking.

Furthermore, in this embodiment, the seal member 54 has the tackiness after being hardened. Therefore, even when the header tank 5a is reversed so that the seal member 54 faces the lower side in such a manner that the seal member 54 having been hardened is placed at the seal surface 53 of the tank body 50b of the header tank 5a, 5b, the seal material 54 can tightly contact the seal surface 51c of the core plate 50a of the header tank 5a, 5b without leaving the seal surface 51c.

Therefore, after the seal members 54 are respectively applied to the header tanks 5a and 5b and the seal members 54 are hardened, the seal members 54 can be faced toward free direction. Thus, the tank body 50b of the header tank 5a and that of the header tank 5b can be respectively fastened to the core plates 50a simultaneously. Accordingly, it takes short time to fasten, as compared with a comparison example where a tank body and a core plate of each of header tanks are fastened separately at different times. Therefore, the manufacture cost can be reduced.

In this embodiment, because the gel seal material or the liquid seal material is applied to the core plate 50a to construct the seal member 54, the seal member 54 having a complex shape can be readily provided with a low cost. Thus, it is unnecessary to prepare the seal members having different shapes and sizes corresponding to the header tanks.

In this embodiment, the lap portion 73 where the applying start position 71 and the applying finish position 72 of the seal material are overlapped is provided. The lap portion 73 is positioned at the straight portion 80 of the seal surface 53.

There is apprehension that a gap may occur between the start position 71 and the applying finish position 72 of the seal material so that cooling water leaks from the gap. According to this embodiment, because the straight portion 80 having a substantially linear shape is provided for the seal surface 53, the seal material can be readily applied and the shape of the seal member 54 can be readily regulated. Thus, the gap can be reduced and the leakage of cooling water can be restricted.

Moreover, because the nail portion 51a is arranged to overlap the lap portion 73, the stress is applied to the lap portion 73 by the nail portion 51a so that the seal member 54 is resiliently deformed. Therefore, slight gap can be restricted from occurring at the lap portion 73. Thus, the leakage of cooling water can be further restricted.

Furthermore, because the seal material is applied such that the seal member 54 has a shape convex toward the upper side (that is, opposite side to seal surface 51c), the seal member 54 having been hardened can be readily compressed and the compression rate can be readily ensured. Therefore, the core plate 50a and the tank body 50b can be substantially tightly contacted with each other.

Second Embodiment

In the above-described first embodiment, the one tank inner space is formed in the header tank 5a. According to a second embodiment of the present invention, the multiple tank inner spaces (for example, two tank inner spaces) are formed in the header tank 5a.

As shown in FIG. 10, for example, a partition wall 6c is arranged in the tank body 50b to partition the space in the tank body 50b into the two tank inner spaces 60a and 60b. With reference to FIG. 11, the seal surface 51c having the ring shape and a seal surface 51d corresponding to the partition wall 6c are arranged at the core plate 50a. That is, each of the inner spaces in the header tank 5a is surrounded by the seal member 54.

In this case, the seal material is applied along the seal surface 51c and the seal surface 51d to respectively surround the inner space 60a and the inner space 60b. As shown in FIG. 12 which is a cross section taken along the line XII-XII in FIG. 11, the bottom of the groove portion 51b of the core plate 50a constructs the seal surface 51d.

In the second embodiment, the applying process and the hardening process of the seal member 54 are the same with the first embodiment, and the descriptions thereof are omitted.

According to the second embodiment, the intake pipe 6a and the outtake pipe 6b are respectively arranged at the two ends (e.g., upper end and lower end in FIG. 10) of the header tank 5a. In this case, the header tank 5b is not provided with the intake pipe 6a and the outtake pipe 6b.

According to this embodiment, the tubes 2 and the fins 3 which are positioned at the side (e.g., upper side of FIG. 10) of the intake pipe 6a construct a core unit 40a, and the tubes 2 and the fins 3 which are positioned at the side (e.g., lower side of FIG. 10) of the outtake pipe 6b construct a core unit 40b. In the header tank 5a, the cooling water flowing from the intake pipe 6a into the inner space 60a is distributed to the tubes 2 of the core unit 40a of the upper side of FIG. 10, and flows into the header tank 5b after being cooled in the tubes 2.

Thereafter, cooling water is distributed from the header tank 5b to the tubes 2 of the core unit 40b of the lower side of FIG. 10, and flows into the inner space 60b of the header tank 5a after being cooled at the tube 2. Then, cooling water returns to the engine from the outtake pipe 6b.

Third Embodiment

A third embodiment according to the present invention will be described with reference to FIG. 13. According to this embodiment, a recess 51e is formed at the bottom of the groove portion 51b (having U-like shaped cross section) of the core plate 50a of the header tank 5b, and is positioned within the seal surface 51c of the core plate 50a.

The recess 51e extends around the periphery of the core plate 50a along the seal surface 51c, to have a ring shape. In this case, the gel seal material or the liquid seal material is applied to fill the recess 51e, and hardened.

Thus, the seal material is hardened in such a manner that the seal material is engaged in the recess 51e, so that it is difficult for the seal member 54 to leaving the seal surface 51c. Therefore, when the core plate 50a and the tank body 50b are fastened to each other, the position deviation can be further reduced as compared with the first and the second embodiment.

Fourth Embodiment

According to a fourth embodiment of the present invention, the seal member 54 can be constructed by applying the seal material to the seal surface 53 of the tank body 50b.

FIGS. 14 and 15 show the construction of the header tank 5a, 5b where the manufacture method according to the fourth embodiment is applied. In this case, the end portion 52 of the tank body 50b which is not provided with the protrusion 53a is exampled. However, the manufacture method according to the fourth embodiment can be also applied to the tank body 50b having the construction described in the first-third embodiments.

In the fourth embodiment, the end portion 52 of the tank body 50b is inserted in the groove portion 51b. The seal member 54 having the ring shape is arranged between the seal surface 53 (where protrusion 53a is omitted) of the end portion 52 and the seal surface 51c of the core plate 50a.

Next, the manufacture method of the radiator 1 according to the fourth embodiment will be described.

At first, the multiple tubes 2, the core plates 50a, the fins 3 and the side plates 4a and 4b are prepared.

Next, the multiple tubes 2 are arrayed to be spaced from each other at a predetermined distance. The fins 3 are arranged so that the adjacent tubes 2 are separated from each other by the fin 3. Thus, the core unit 4 is temporarily assembled. Thereafter, the tubes 2 and the side plates 4a and 4b are inserted through the through holes 56 of the core plate 50a of the header tank 5a.

Next, the inner diameter of the one end (that is, the part which penetrates core plate 50a to be positioned in the part corresponding to tank space 50c) of the longitudinal direction of the tube 2 is enlarged, so that the tube 2 and the core plate 50a are fixed to each other.

Then, the tubes 2 and the side plates 4a and 4b are inserted through the through holes 56 of the core plate 50a of the header tank 5b. In this case, the inner diameter of the other end of the longitudinal direction of the tube 2 is enlarged, so that the tube 2 and the core plate 50a of the header tank 5b are fixed to each other.

Thus, the temporary assembly of the core plates 5oa of the header tanks 5a, 5b, the tubes 2, the fins 3 and the side plates 4a and 4b is provided. The assembly is held by a jig and heated in a furnace. Then, as shown in FIG. 5, the tubes 2, the fins 3, the side plates 4a and 4b and the core plates 5oa of the header tanks 5a, 5b are integrated with each other by brazing, for example.

Next, as shown in FIG. 16A, the applying process is performed. An injector 60 or the like in which the gel seal material or the liquid seal material is filled, and the tank body 50b of the header tank 5a are prepared. Then, the seal surface 53 of the tank body 50b is faced to the upper side, and the seal material is applied the seal surface 53 through the injector 60.

The seal material is applied to the seal surface 53 in such a manner that the cross section of the seal member 54 has a convex shape (e.g., semicircle shape), as shown in FIG. 16A. That is, the seal member 54 convexes to the opposite side of the seal surface 53.

As shown in FIGS. 17 and 18, because the seal surface 53 of the tank body 50b has the ring shape, the seal material is applied such that the applying start position 71 and the applying finish position 72 of the seal material are overlapped with each other at least at one lap portion 73.

In this case, as shown in FIG. 17, the lap portion 73 is arranged at the straight portion 80 (which straightly extends) of the seal surface 53 which has the ring shape. Moreover, the seal material of the seal member 54 from the injector 60 is also applied to the seal surface 53 of the header tank 5b.

Thereafter, the hardening process is performed, as shown in FIG. 16B. The seal material having been applied to the tank bodies 50b of the header tank 5a and the header tank 5b is irradiated with ultraviolet light, for example. Thus, the seal member 54 is constructed.

Next, as shown in FIG. 16C, the seal member 54 applied to the tank body 50b of the header tank 5a is contacted with the seal surface 51c of the core plate 50a. Then, the fastening process is performed. As shown in FIG. 16D, the nail portions 51a are swaged so that the tank body 50b and the core plate 50a are fastened to each other. In this case, at least one of the nail portions 51a is arranged to overlap the lap portion 73. Thus, the manufacture of the header tank 5a is finished.

Similarly, the seal member 54 applied to the tank body 50b of the header tank 5b is contacted with the seal surface 51c of the core plate 50a. Then, the fastening process is performed. The nail portions 51a are swaged so that the tank body 50b and the core plate 50a are fastened to each other. In this case, at least one of the nail portions 51a is arranged to overlap the lap portion 73. Thus, the manufacture of the header tank 5b is finished

In this embodiment, before the fastening of the tank body 50b with the core plate 50a, the gel seal material or the liquid seal material is applied to the seal surface 53 of the header tank 5a, 5b and then hardened. Thus, the seal member 54 tightly contacts the seal surface 53 where the seal member 54 is applied, to be restricted from twisting and position-deviating. The core plate 50a and the tank body 50b are fastened with each other in such a manner that the seal member 54 seals the part between the seal surface 51c of the core plate 50a and the seal surface 53 of the tank body 50b. Therefore, when the core plate 50a and the tank body 50b are fastened with each other, the part between the seal surface 51c of the core plate 50a and the seal surface 53 of the tank body 50b can be sealed. Thus, cooling water can be restricted from leaking.

Furthermore, in this embodiment, the seal member 54 has the tackiness after being hardened to tightly contact the side of the tank body 50b. Therefore, even when the header tank 5ais reversed so that the seal member 54 having been hardened is placed at the seal surface 51c of the header tank 5a, 5b, the seal material 54 can tightly contact the seal surface 53 of the tank body 50b without leaving the seal surface 53.

Therefore, the seal members 54 can be faced toward free direction. Thus, after the seal members 54 are respectively applied to the header tanks 5a and 5b and the seal members 54 are hardened, the tank body 50b of the header tank 5a and that of the header tank 5b can be respectively fastened to the core plates 50a simultaneously.

In this embodiment, because the gel seal material or the liquid seal material is applied to the tank body 50b to construct the seal member 54, the seal member 54 having a complex shape can be readily provided with a low cost. Thus, it is unnecessary to prepare the seal members having different shapes and sizes corresponding to the header tanks. Moreover, even when the seal surface 53 of the tank body 50b has a complex shape, the seal material can be readily applied along the seal surface 53.

In this embodiment, the lap portion 73 where the applying start position 71 and the applying finish position 72 of the seal material are overlapped is provided. The lap portion 73 is positioned at the straight portion 80 of the seal surface 53.

There is apprehension that a gap may occur between the start position 71 and the applying finish position 72 of the seal material so that cooling water leaks from the gap. According to this embodiment, the seal material is applied to the straight portion 80. Because the seal material can be more readily applied to the straight portion 80 having the substantially linear shape than the corner portion (bent portion), the shape of the seal member 54 can be readily regulated. Thus, the gap can be reduced and the leakage of cooling water can be restricted.

Moreover, because the nail portion 51a is arranged to overlap the lap portion 73, the pressure can be applied to the lap portion 73 (seal member 54) by the nail portion 51a through the end portion 52 of the tank body 50b. Therefore, slight gap can be restricted from occurring at the lap portion 73. Thus, the leakage of cooling water can be further restricted, because the seal member 54 is tightly contacted with the seal surface 51c of the core plate 50a and the seal surface 53 of the tank body 50b.

Furthermore, because the seal material is applied such that the seal member 54 has a shape convex toward the upper side (that is, opposite side to seal surface 53), the seal member 54 having been hardened can be readily compressed and the compression rate can be readily ensured. Therefore, the core plate 50a and the tank body 50b can be substantially tightly contacted with each other.

Fifth Embodiment

According to a fifth embodiment of the present invention, as shown in FIG. 19, the seal surface 53 of the tank body is provided with a groove portion.

In this case, the seal material is applied such that the groove portion is filled. Therefore, it is difficult for the seal member 54 having been hardened to leave the seal surface 53. Accordingly, the position deviation of the seal member 54 can be substantially restricted.

The groove portion can have a cross section with a substantially semicircular shape, a substantially triangle shape or other shape.

Sixth Embodiment

According to a sixth embodiment of the present invention, as shown in FIG. 20, the seal surface 53 of the tank body is provided with minute projections and depressions.

In this case, the seal material is applied such that the projections and depressions are filled. Thus, the seal member 54 is engaged with the projections and depressions, so that the position deviation of the seal member 54 can be substantially restricted.

Seventh Embodiment

In the above-described fourth-sixth embodiment, the one tank inner space is formed in the header tank 5a. According to a seventh embodiment of the present invention, the multiple tank inner spaces (for example, two tank inner spaces) are formed in the header tank 5a.

As shown in FIG. 10, for example, the partition wall 6c is arranged in the tank body 50b to partition the space in the tank body 50b into the two tank inner spaces 60a and 60b. With reference to FIG. 21, the seal surface 53 having the ring shape is also formed at the end surface of the partition wall 6c. That is, each of the inner spaces 60a and 60b in the header tank 5a is surrounded by the seal member 54.

In the seventh embodiment, the applying process and the hardening process of the seal member 54 are the same with the fourth embodiment, and the descriptions thereof are omitted.

According to the seventh embodiment, the intake pipe 6a and the outtake pipe 6b are respectively arranged at the two ends (e.g., upper end and lower end in FIG. 10) of the header tank 5a. In this case, the header tank 5b is not provided with the intake pipe 6a and the outtake pipe 6b.

According to this embodiment, the tubes 2 and the fins 3 which are positioned at the side (e.g., upper side of FIG. 10) of the intake pipe 6a construct a core unit 40a, and the tubes 2 and the fins 3 which are positioned at the side (e.g., lower side of FIG. 10) of the outtake pipe 6b construct a core unit 40b. In the header tank 5a, the cooling water flowing from the intake pipe 6a into the inner space 60a is distributed to the tubes 2 of the core unit 40a of the upper side of FIG. 10, and flows into the header tank 5b after being cooled in the tubes 2.

Thereafter, cooling water is distributed from the header tank 5b to the tubes 2 of the core unit 40b of the lower side of FIG. 10, and flows into the inner space 60b of the header tank 5a after being cooled at the tube 2. Then, cooling water returns to the engine from the outtake pipe 6b.

Other Embodiments

Although the present invention has been fully described in connection with the preferred embodiments thereof with reference to the accompanying drawings, it is to be noted that various changes and modifications will become apparent to those skilled in the art.

For example, the three or more tank inner spaces can be also formed in the header tank 5a.

Moreover, in the above-described embodiments, the seal material is applied to the seal surface 51c of the core plate 50a and then hardened. Alternatively, the seal material can be simultaneously hardened when being applied to the seal surface 51c of the core plate 50a, to construct the seal member 54.

In this case, while the seal material is applied to the seal surface 51c of the core plate 50a, the seal material is irradiated by ultraviolet light, for example.

In this case, the seal material can be also heated to be hardened while being applied to the seal surface 51c of the core plate 50a, in the case where the thermosetting resin or the like is used as the seal material.

In the above-described embodiment, after the tubes 2 are joined to the core plate 50a by brazing, the gel seal material or the liquid seal material is applied to the seal surface 51c of the core plate 50a. However, the gel seal material or the liquid seal material can be also applied to the seal surface 51c of the core plate 50a, before the tubes 2 are joined to the core plate 50a by brazing.

In addition to the radiator, the heat exchanger according to the present invention in which the header tanks 5a and 5bare respectively constructed of the core plate 50a and the tank body 50b can be also suitably used as an evaporator, a heater core unit and the like. In this case, fluid other than engine cooling water can be also used.

Moreover, in the above-described embodiments, the seal material is applied to one of the seal surface 51c of the core plate 50a and the sea surface 53 of the tank body 50b. However, the seal material can be also applied to both of the seal surface 51c of the core plate 50a and the seal surface 53 of the tank body 50b.

Such changes and modifications are to be understood as being in the scope of the present invention as defined by the appended claims.