JP2000158070A - Tube for heat exchanger - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a tube for heat exchanger capable of preventing joined parts from peeling off without needing the labor and time for formation. SOLUTION: This tube 14 is formed so that both edge parts 17 in the bending direction of a metal plate 16 bent to tubular shape are brazed each other and are brazed to the inner face of the metal plate 16. First joining parts 18 bent about 90 deg. toward the inner face side of the metal plate 16 are respectively formed to both edge parts 17. Second joining parts 19 bent about 90 deg. for the first joining parts and parallel to the inner face the metal plate 16 are respectively formed to these first joining parts 18. Further, at both edge parts 17, the first joining parts 18 are brazed in the thickness direction each other, the thickness direction side face at the second joining parts 19 are brazed to the inner face of the metal plate 16.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a heat exchanger tube used in a heat exchanger such as a radiator of an automobile and through which a fluid for heat exchange flows.

[0002]

2. Description of the Related Art Generally, an automobile equipped with an internal combustion engine is provided with a heat exchanger such as a radiator for cooling superheated cooling water in a circulation path for circulating cooling water for the internal combustion engine. Such a heat exchanger is provided with a plurality of tubes through which cooling water flows, and heat exchange is performed between air impinging on the tubes and cooling water in the tubes, thereby cooling the cooling water flowing through the circulation path. You will be

[0003] The tube of the heat exchanger is formed by brazing two edges in the bending direction of a tubular metal plate to each other. As a tube formed in this manner, for example, a tube described in Japanese Patent Application Laid-Open No. H10-193003 is known. Here, the heat exchanger tubes described in the publication are shown in FIGS.

[0004] The tube 71 shown in FIG. 4 is formed of a metal plate 72 bent in a tubular shape. That is, both edges 73 in the bending direction of the metal plate 72 are bent toward the inner surface of the metal plate 72,
The tube 71 is formed by brazing the both edges 73 together with the inner surface of the metal plate 72.

[0005] The tube 74 in FIG. 5 also comprises a metal plate 72 bent in a tubular shape. That is, one of the both ends 73a and 73b in the bending direction of the metal plate 72 is bent into a U-shape and the other is bent toward the inner surface of the metal plate 72, and the other is bent to the U-shaped edge 73a. They are brazed to each other with the edge 73b inserted. Then, the tube 74 is formed by similarly brazing the U-shaped edge 73 a to the inner surface of the metal plate 72.

[0006] In the tubes 71 and 74, both of them are both edges 73, 73 a and 73 b of the metal plate 72.
Is brazed to the inner surface of the metal plate 72, and the brazing ensures the required strength.

However, as is apparent from FIGS. 4 and 5, only the ends of the edges 73, 73a facing the inner surface of the metal plate 72 are soldered to the inner surface of the metal plate 72. Therefore, there is a possibility that the joints between the inner surface of the metal plate 72 and the edges 73 and 73a may be peeled off due to aging or the like, and the tubes 71 and 74 may be peeled off due to such peeling.
, The strength of the steel is greatly reduced. Therefore, a tube having a joint structure in which a joint portion is unlikely to peel off has been proposed, such as a tube described in Japanese Patent Application Laid-Open No. 10-47875. FIG. 6 shows a tube described in the publication.

The tube 75 shown in FIG. 1 also comprises a metal plate 72 bent in a tubular shape. That is, the protrusion 76 is formed at the center of the metal plate 72 in the bending direction, and the protrusion 76 is formed.
The tube 75 is formed by brazing the opposing inner surfaces of the metal plate 72 to both sides 73b of the metal plate 72 in the bending direction on the side in the thickness direction of the projection 76. In such a tube 75, the side surface in the thickness direction of both edges 73c is the inner surface of the metal plate 72 (the side surface in the thickness direction of the projection 76).
Therefore, the joint between the both edges 73c and the inner surface of the metal plate 72 does not easily come off.

[0009]

As described above, in the tube 75, the joint between the both edges 73c of the metal plate 72 and the inner surface does not easily come off. However, since the projection 76 must be formed, the tube 75 must be formed. The work of bending and forming 75 is complicated. That is, when the tube 75 is formed, the number of bent portions of the metal plate 72 is increased by the amount of the protrusions 76, and the labor involved in the bending work cannot be ignored.

The present invention has been made in view of such circumstances, and an object of the present invention is to provide a tube for a heat exchanger which can prevent peeling of a joint portion without troublesome formation. is there.

[0011]

In order to achieve the above object, according to the first aspect of the present invention, both edges in the bending direction of a tubular bent plate are joined to each other and joined to the inner surface of the plate. Heat exchanger tubes,
A first joining portion formed at each of the two edges by bending both edges in the bending direction of the plate toward the inner surface of the plate, and joined to each other in its own thickness direction; By bending at least one of the joining portions, a portion of the first joining portion on the inner surface side of the plate material is formed parallel to the inner surface, and the inner surface of the plate material and its own thickness direction side surface are joined. A second joint.

According to this structure, since the thickness side surface of the second joining portion parallel to the inner surface of the plate is joined to the inner surface of the plate, the joint can be prevented from peeling off. become. Also, since the second joint is formed simply by bending the first joint, the second joint
It does not take too much time to form the joint.

According to a second aspect of the present invention, in the first aspect of the present invention, the two joints are provided on both of the first joints, respectively, in a direction away from the first joints. It was bent to be parallel to the inner surface of the plate.

[0014] According to this structure, the joint surface between the second joint portion and the plate member can be made large, so that the joint portion between them can be more accurately prevented from peeling off.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment in which the present invention is applied to a radiator for an automobile will be described below with reference to FIGS.

As shown in FIG. 1, a radiator 11 includes an upper tank 12 and a lower tank 13 extending in parallel with each other.
And a plurality of tubes 14 provided between the tanks 12 and 13. In the radiator 11, the tubes 14 are located at equal intervals in the direction in which the upper tank 12 and the lower tank 13 extend,
The cooling fins 1 that are curved in a wave shape are provided between the tubes 14.
5 are provided. The upper tank 12 and the lower tank 13 have an upper hose 12a and a lower hose 1 that communicate with a cooling passage (not shown) through which engine cooling water flows.
3a are respectively connected.

Therefore, the cooling water is supplied to and discharged from the radiator 11 through the hoses 12a and 13a. That is, the cooling water for cooling the engine is sequentially supplied to the upper hose 12a and the upper tank 1 from the cooling passage.
2. Tube 14, lower tank 13, and lower hose 13
a, and from the lower hose 13a to the cooling passage again to circulate. Here, the tube 14 and the cooling fins 15 are shown enlarged in FIG.

When the cooling water circulating as described above passes through each tube 14 shown in FIG.
The heat exchange is performed between the air passing through the space 4 and the cooling water in the tube 14, and the heat exchange cools the superheated cooling water in the engine. The heat exchange between the air and the cooling water is efficiently performed by the cooling fins 15 provided between the outer surfaces of the tubes 14.

Next, the tube 14 will be described in detail with reference to FIG. As shown in FIG.
4 is formed by joining both edges 17 in the bending direction of a metal plate 16 made of, for example, aluminum, which is bent into a tube, and also making a solder contact with the inner surface of the metal plate 16. In the tube 14, a first joint portion 18 that is bent by about 90 ° toward the inner surface side of the metal plate 16 with respect to both edges 17 of the metal plate 16 that is bent into a tubular shape, respectively. Is formed. In addition, those first
In the portion on the inner surface side of the metal plate 16 at the joint 18 of
Each of the second joints 19 is formed to bend by about 90 ° in a direction away from each other with respect to the first joint 18 and to be parallel to the inner surface of the metal plate 16. Then, the both edge portions 17
In this case, the first joints 18 are brazed to each other in the thickness direction, and the side surfaces in the thickness direction of the second joints 19 are brazed to the inner surface of the metal plate 16.

Here, a method for manufacturing the tube 14 will be described. The metal plate 16 forming the tube 14 is provided with a rust prevention layer on one surface in the thickness direction to prevent corrosion due to rust. Then, as shown in FIG. 3A, the bending direction (left-right direction in the figure) of the metal plate 16
Are bent about 90 ° upward in the figure.
By bending both edges 17 in this manner, the edges 1
First joints 18 are formed on the respective sections 7. In FIG. 3A, the rust prevention layer is formed on the side of the surface located above the metal plate 16.

Subsequently, the first joint portion 18 is bent by about 90 ° to a position shown by a two-dot chain line L1 in the figure so that the end portions thereof face each other. By bending the first joint 18 in this manner, a second joint 19 is formed on the end side of the first joint 18. The first and second joints 18 and 19 formed on both edges 17 in this manner are connected to the metal plate 16.
Are symmetric with respect to a vertical plane F passing through the center M in the bending direction and extending parallel to the first joint portion 18.

After the first and second joints 18 and 19 are formed, the metal plate 16 is bent at an intermediate position between the vertical plane F and both edges 17 as shown by a two-dot chain line L2 in the figure. Can be By this bending, the first joint portions 18 at both edges 17 are overlapped with each other in the thickness direction, and the side surfaces in the thickness direction of the second joint portions 19 are overlapped on the inner surface of the metal plate 16. In this state, the first joints 18 are brazed to each other in the thickness direction, and the side surfaces in the thickness direction of the second joints 19 are brazed to the inner surface of the metal plate 16, as shown in FIG. Thus, the tube 14 is formed.

In the tube 14 thus formed, since the side surface in the thickness direction of the second joint portion 19 is brazed to the inner surface of the metal plate 16, the joint portion is prevented from peeling due to aging or the like. Is done. Also, the second joint 19
Is formed simply by bending the first joint 18 by about 90 °, so that the second joint 19 is easily formed. Therefore, it is possible to prevent the joint portion between the second joint portion 19 and the metal plate 16 from being peeled off without troublesome formation of the tube 14.

The second joints 19 formed on both edges 17 are bent by about 90 ° with respect to the first joint 18 in a direction away from each other. Therefore, the metal plate 1
6, the joint surface 19a of the second joint portion 19 with respect to the inner surface of the metal plate 16 can be made wider, so that the joint portion between the second joint portion 19 and the metal plate 16 can be more accurately prevented from peeling.

The width a of the tube 14 is
Is determined by the length from the joint portion of the second joint portion 19 to the inner surface of the metal plate 16 to the portion where the metal plate 16 is bent to form the first joint portion 18. Second joint 1
9 can be made wider as described above, so that the second joint portion 19 and the metal plate 16
And the joining portion is accurately brazed, and the accuracy of the width a having the joining portion as one end can be improved.

Further, in the tubular metal plate 16,
Since an antirust layer is formed on the inner surface side in advance, the entire inner surface of the tube 14 after the formation is covered with the antirust layer. Therefore, the rust prevention layer makes it possible to prevent the inside of the tube 14 through which the engine cooling water flows from being corroded by rust.

According to the embodiment described above, the following effects can be obtained. (1) The joint between the second joint 19 and the metal plate 16 can be accurately prevented from peeling off without taking time to form the tube 14.

(2) The accuracy of the width a of the tube 14 can be improved. (3) Corrosion of the inside of the tube 14 due to rust can be suppressed. Note that the present embodiment can be modified as follows, for example.

In this embodiment, the metal plate 16 may be formed of another material instead of aluminum. -Although the 2nd joint part 19 was bent in the direction which is mutually spaced apart to the 1st joint part 18, you may instead bend both the 2nd joint parts 19 about 90 degrees in the same direction. .

The second joints 1 formed on both edges 17
9 may be omitted. In this case, the material for forming the tube 14 can be reduced. The length of the second joint 19 in the direction orthogonal to the width a of the tube 14 may be changed as appropriate.

In this embodiment, the radiator 1 of the vehicle
1, the present invention may be applied to other heat exchangers such as a heater core, an evaporator, a condenser, and an intercooler of an air conditioner.

Next, technical ideas other than the claims that can be grasped from the above embodiments will be described below together with their effects. (1) A tube formed by joining both edges in a bending direction of a plate material bent into a tube and joining the inner surface of the plate material with a fluid for heat exchange flowing through the tube; In a heat exchanger that performs heat exchange between the inside and the outside of the plate, both edges in the bending direction of the plate are bent toward the inner surface of the plate to form first joints at the both edges, respectively. By bending at least one of the first bonding portions, a second bonding portion parallel to the inner surface is formed at a portion of the first bonding portion on the inner surface side of the plate member, and the first and second bonding portions are formed. A heat exchanger, wherein the tubes are formed by joining the joints in the thickness direction to each other in the thickness direction, and joining the side surface in the thickness direction of the second joint to the inner surface of the plate material.

According to the above construction, the second joint which is parallel to the inner surface of the plate is easily formed by bending the first joint, and the thickness side surface of the second joint is connected to the plate. Since the inner surface of the tube is joined, it is possible to prevent the joint portion from peeling off without any trouble in forming the tube.

(2) In the heat exchanger according to the above (1), the second joint is formed by bending both first joints in a direction away from each other to form the first joints. The heat exchanger formed in the inner surface side of each said board | plate material in in parallel with the said inner surface.

According to this structure, the joint surface between the second joint portion and the plate member can be made large, so that peeling of the joint portion between them can be more accurately prevented.

[0036]

According to the first aspect of the present invention, the second joint which is parallel to the inner surface of the plate is easily formed by bending the first joint, and the second joint is formed. Since the side surface in the thickness direction and the inner surface of the plate member are joined, peeling of the joined portion can be prevented without troublesome tube formation.

According to the second aspect of the present invention, the joint surface between the second joint portion and the plate member can be made large, so that the joint portion between the two can be more accurately prevented from peeling off.

[Brief description of the drawings]

FIG. 1 is a front view showing a radiator to which a tube according to an embodiment is applied.

FIG. 2 is an enlarged view showing tubes and cooling fins of the radiator.

FIG. 3 is an explanatory view showing a tube forming procedure and a tube after formation.

FIG. 4 is a view showing a conventional example of a tube.

FIG. 5 is a diagram showing another conventional example of a tube.

FIG. 6 is a view showing still another conventional example of a tube.

[Explanation of symbols]

11 radiator, 12 upper tank, 12a upper hose, 13 lower tank, 13a lower hose, 14
Tube, 15: cooling fin, 16: metal plate, 17: edge, 18: first joint, 19: second joint, 19a
… Joining surface.

Claims (2)

[Claims] 1. A heat exchanger tube formed by joining both edges in the bending direction of a plate material bent into a tube and joining the inner surfaces of the plate material to each other. By bending toward the inner surface of the first joint formed at each of the two edges and joined to each other in its thickness direction, by bending at least one of the first joint, A second joint formed parallel to the inner surface of the plate at the first joint in the inner surface of the plate, and joined to the inner surface of the plate and its thickness direction side surface. Characteristic tube for heat exchanger. 2. The plate according to claim 1, wherein the two joints are provided at the two first joints, respectively, and are bent in a direction away from the first joints so as to be parallel to the inner surface of the plate. A heat exchanger tube as described.