JP3205348B2 - Manufacturing method of aluminum heat exchanger - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement in a method for manufacturing an aluminum heat exchanger used as a capacitor or the like constituting an air conditioner for a vehicle, and to prevent the occurrence of defective products due to defective brazing. Things.

[0002]

2. Description of the Related Art As a heat exchanger used as a condenser of a vehicle air conditioner, for example, Japanese Utility Model Laid-Open Publication No. 64-8081 discloses an aluminum heat exchanger having a structure as shown in FIG. This conventional heat exchanger has an inlet header 2 made of aluminum (aluminum or aluminum alloy; same throughout the present specification) having an inlet pipe 1 connected to an upper end face, and an inlet header 2 made of aluminum. A plurality of heat transfer tubes 5 and 5 connect the outlet side header 4 having the outlet tube 3 connected to the lower end surface thereof in parallel, and a corrugated fin 6 between adjacent heat transfer tubes 5 and 5. 6 is sandwiched. When heat exchange is performed between a fluid such as a refrigerant and air, the fluid is sent from the inlet pipe 1 and taken out from the outlet pipe 3, and the fluid flows from the inlet header 2 to the outlet header 4. While flowing through the heat transfer tubes 5, 5, heat is exchanged with the air flowing around.

In the case of an aluminum heat exchanger constructed and operated as described above, the performance of the heat exchanger is improved by lengthening the flow path of a fluid such as a refrigerant flowing through the heat transfer tubes 5. For this reason, the partition walls 7, 7 are provided at an intermediate portion between the headers 2, 4. For example, in the case of the structure shown in FIG. 9, one partition 7 is fixed to each of the inside of the entrance-side header 2 and the inside of the exit-side header 4. For this reason, the fluid such as the refrigerant sent from the inlet pipe 1 to the inlet header 2 is first sent to the outlet header 4 through some of the heat transfer pipes 5, 5, and from this outlet header 4 again to another heat transfer pipe It is returned to the inlet header 2 through 5, 5 and further sent to the outlet header 4 through the remaining heat transfer tubes 5, 5, and then sent out from the outlet tube 3.

As described above, the partition 7 for dividing the inside of the entrance header 2 or the exit header 4 into a plurality of chambers is shown in FIG.
As shown in 0 to 11, it is mounted inside the entrance header 2 (or the exit header 4; the same applies hereinafter). That is, a slit-shaped insertion hole 8 is formed on the side surface of the entrance-side header 2 just over half the circumference of the entrance-side header 2. The plate piece 9 constituting the partition wall 7 has a small-diameter side semicircular arc portion 10 having an outer peripheral edge coinciding with the inner peripheral surface of the entrance side header 2 and a large diameter having an outer peripheral edge almost coincident with the outer peripheral surface of the entrance side header 2. Steps 12 and 12 are formed in a continuous portion between the two semicircular arc portions 10 and 11.

[0005] The plate piece 9 thus formed is inserted into the insertion hole 8 from the side of the small-diameter side semi-circular portion 10, and the outer peripheral edge of the small-diameter side semi-circular portion 10 and the entrance side header 2 are formed. By liquid-tight brazing between the inner peripheral surface and between the inner peripheral edge of the insertion hole 8 and the outer peripheral portion of the large diameter semicircular arc portion 11,
The partition 7 is used. That is, since a brazing material layer is present on the surfaces of the plate piece 9 and the entrance-side header 2 each made of a so-called clad material formed by laminating a core material and a brazing material, aluminum heat exchange is performed. If the components of the vessel are heated in a state in which they are temporarily assembled as shown in FIG. 9, the space between the outer peripheral edge of the small diameter side semicircular arc portion 10 and the inner peripheral surface of the entrance side header 2 is reduced.
In addition, the space between the inner peripheral edge of the insertion hole 8 and the large diameter side semicircular arc portion 11 is brazed in a liquid-tight manner.

[0006]

However, in the case of manufacturing an aluminum heat exchanger as described above,
Conventionally, the following problems have occurred.

That is, in order for an aluminum heat exchanger in which the inside of the entrance-side header 2 is partitioned by the partition 7 to exhibit the performance as designed, the sealing of the partition 7 installation portion is surely performed. Things are necessary. For example, based on poor brazing between the outer peripheral edge of the small-diameter side semicircular arc portion 10 of the plate piece 9 and the inner peripheral surface of the entrance-side header 2, the seal at the portion where the partition wall 7 is installed is incomplete and fluid such as refrigerant If the gas is bypassed at the portion where the partition wall 7 is installed, the amount of fluid flowing through the heat transfer tubes 5, 5 is reduced by that much, and the performance of the aluminum heat exchanger is deteriorated (the performance as designed is not exhibited) Te).

[0008] However, the conventional manufacturing method, when manufacturing aluminum heat exchanger, such as shown in FIG. 9, the
Outer peripheral edge of small-diameter side semicircular portion 10 of plate piece 9 and entrance-side header 2
Brazing material should Kyosu brazing between the inner peripheral surface of not easily washed away in the second outer inlet side header through the insertion hole 8. And
In the case of the erosion, the brazing filler metal present at the portion where the partition wall 7 is provided is insufficient, and the above-described bypass that easily leads to performance degradation is likely to occur.

That is, when the aluminum heat exchanger is temporarily assembled as shown in FIG.
A large number of minute gaps are formed in the core portion 13 including the fins 6. These many small gaps tend to suck a relatively large amount of the molten brazing material due to the capillary phenomenon. Therefore, if the configuration of each part of the aluminum heat exchanger, and heated while assembled provisionally to the state shown in FIG. 9, was dissolved a brazing material layer of each constituent component surface, the plate
Melting out from the surface of the piece 9 or the inner peripheral surface of the inlet side header 2
The outer peripheral edge and the entrance of the small diameter side semicircular arc portion 10 of the plate piece 9
Brazing material should Kyosu brazing between the inner circumferential surface of the side header 2, through the gap between the insertion hole 8 and the plate pieces 9, is drawn into the core unit 13, to the partition 7 installed part The existing brazing material tends to be insufficient, and the sealing performance at the portion where the partition wall 7 is installed is likely to be incomplete.

[0010] For example, according to the inventor's experiment, the width of the gap 14 between the outer peripheral edge of the small-diameter side half arc portion 10 of the plate piece 9, and the inner peripheral surface of the inlet side header 2 l (Figure 11) Is 0.2
If it exceeds mm, it becomes impossible to hold a sufficient amount of brazing material in the gap 14 during heating for brazing each component of the aluminum heat exchanger, and
The sealing performance of the installation part is incomplete, and the performance of the aluminum heat exchanger is deteriorated (performance as designed is not exhibited).

Therefore, in order to prevent the fluid from being bypassed at the portion where the partition wall 7 is installed, it is necessary to strictly control the dimensional accuracy and the assembling accuracy of each component, and the processing cost of the aluminum heat exchanger is reduced. It will be bulky.

[0012] aluminum production method of the heat exchanger of the present invention has considered in view of the circumstances as described above, the core unit 1 brazing material, through the insertion hole 8 formed in the partition wall 7 installed part
By preventing the suction by 3, the gap 14 can be reliably closed without strictly regulating the dimensional accuracy and assembly accuracy of the components.

[0013]

SUMMARY OF THE INVENTION According to the present invention, there is provided a method for manufacturing an aluminum heat exchanger.
A pair of aluminum headers, a plurality of aluminum heat transfer tubes each having both ends passing through both headers, an aluminum fin sandwiched between adjacent heat transfer tubes, and at least one header And a partition made of aluminum that divides the inside of the header into a plurality of chambers, the method comprising: a core material and a brazing material;
A clad material formed by laminating a core material and a brazing material into a slit-shaped insertion hole formed on the side surface of the header on which the partition wall is to be provided , which is constituted by a clad material formed by laminating
After inserting the plate pieces configured in a shape to cover the inner section of the header, closing by welding at least a majority of the gap between the inner periphery of the plate piece and the insertion hole, and then, an aluminum heat exchanger Are heated in a state in which the constituent parts are temporarily assembled, and these constituent parts are brazed and joined together, and at the same time, the space between the plate piece and the header is liquid-tightly brazed.

[0014]

The method for manufacturing an aluminum heat exchanger according to the present invention is constructed as described above, but before the heating for brazing, the plate piece for forming the partition wall and the inner peripheral edge of the insertion hole are formed. Since the gap between them is closed by welding, the brazing material existing in the partition wall installation portion does not flow through the insertion hole.

For this reason, the outer periphery of the plate piece and the inner periphery of the header are provided.
Brazing filler metal that should close the gap between the surface and
No longer occurs, and a sufficient amount of brazing material remains in the above-mentioned partition wall installation portion, and the sealing performance of the partition wall installation portion is sufficiently maintained.

[0016]

Next, the present invention will be described in more detail with reference to the illustrated embodiment.

1 and 2 show a first embodiment of the present invention. As shown in FIG. 9, the aluminum heat exchanger manufactured by the manufacturing method of the present invention is made of aluminum and has an inlet-side header that is spaced apart from each other, as shown in FIG. 2 and an outlet side header 4, a plurality of aluminum heat transfer tubes 5, 5 with both ends passing through both headers 2, 4, and aluminum sandwiched between adjacent heat transfer tubes 5, 5 And fins 6 and 6 made of aluminum. By providing a partition wall 7 at an intermediate portion between the entrance side header 2 and the exit side header 4, the inside of each header 2, 4 is divided into two chambers.

In the manufacturing method of the present invention for manufacturing the aluminum heat exchanger having the above-described structure, the partition wall 7 is formed at an intermediate portion of the inlet header 2 (or the outlet header 4). In this case, first, a plate piece 9 that covers the inner cross section of the entrance-side header 2 is inserted into a slit-shaped insertion hole 8 formed on the side surface of the entrance-side header 2 where the partition 7 is to be provided.

This plate piece 9 is, similarly to the above-described conventional example,
It comprises a small-diameter side semicircular portion 10 having an outer peripheral edge coinciding with the inner peripheral surface of the entrance header 2 and a large-diameter semicircular arc portion 11 having an outer peripheral edge substantially coincident with the outer peripheral surface of the entrance header 2. Step portions 12 and 12 are formed in a continuous portion between semicircular arc portions 10 and 11. Then , such a plate piece 9 is inserted into the inside of the insertion hole 8 from the side of the small diameter side semicircular arc portion 10.

[0020] In this way, if the insertion hole 8 by inserting the plate pieces 9 on the inlet side header 2, then, as shown by cross hatching in Figures 1-2, the plate piece 9 and the insertion hole 8 The gap with the inner peripheral edge of the rim is closed by welding. It is most preferable that the welding completely closes the gap, but it is not always necessary to completely (100
%) Even if there is no blockage, most of the gap is closed , and the brazing material present in the entrance side header 2 through this gap is
It suffices if it is possible to prevent a large amount from flowing out of the entrance header 2 .

After closing the gap between the plate 9 and the inner peripheral edge of the insertion hole 8 in this way, the components of the aluminum heat exchanger are temporarily assembled as shown in FIG. Heat . Then , these components are brazed and joined together, and between the plate piece 9 and the entrance-side header 2, that is, the outer peripheral edge of the small-diameter half-arc portion 10 of the plate piece 9 and the inner periphery of the entrance-side header 2. Between the surface and the large-diameter side semicircular arc portion 11 of the plate piece 9
Between the both sides of the plate piece 9 and both side edges of the insertion hole 8;
A liquid-tight brazing is carried out between the two ends 12 of the insertion hole 8.

As described above, the method for manufacturing an aluminum heat exchanger according to the present invention uses the partition wall 7 before heating for brazing.
In order to close the gap between the plate piece 9 and the inner peripheral edge of the insertion hole 8 by constituting by welding, with heating for brazing,
Even if the core portion 13 (FIG. 9) tends to suck the molten brazing material, the brazing material existing in the portion where the partition wall 7 is provided does not flow through the insertion hole 8.

For this reason, the semicircular portion 10 on the small diameter side of the plate piece 9
Between the outer peripheral edge of the inner side and the inner peripheral surface of the inlet side header 2
The brazing material to be provided may flow out of the header 2 on the entrance side.
As a result, a sufficient amount of brazing material remains in the portion where the partition 7 is provided, and the sealing property of the portion where the partition 7 is provided is sufficiently maintained. For example, according to the experiments conducted by the present inventors, the outer peripheral edge of the small-diameter side half arc portion 10 of the plate piece 9,
Width l of gap 14 between inner peripheral surface of inlet side header 2
Even if (FIG. 11) reaches about 0.7 mm, the gap 14 between the outer peripheral edge of the small-diameter side semicircular arc portion 10 of the plate piece 9 and the inner peripheral surface of the entrance-side header 2 is completely formed by brazing material. It was confirmed that it would be closed.

Next, a second embodiment of the present invention shown in FIGS. 3 and 4 will be described.

In the first embodiment described above, the outer peripheral edge of the large-diameter side semicircular arc portion 11 of the plate piece 9 for forming the partition wall 7 is formed to have a size substantially matching the outer peripheral surface of the entrance side header 2. On the other hand, in the case of the present embodiment, the outer peripheral edge of the large diameter side semicircular arc portion 11 is formed sufficiently larger than the outer peripheral surface of the entrance side header 2. Other configurations and operations are the same as those of the first embodiment.

Next, a third embodiment of the present invention shown in FIGS. 5 and 6 will be described.

In the first and second embodiments described above, the outer peripheral edge of the large-diameter semicircular portion 11 of the plate piece 9 for forming the partition wall 7 has a size substantially matching the outer peripheral surface of the entrance-side header 2. In the case of this embodiment, the outer peripheral edge of the large-diameter semicircular arc portion 11 is smaller than the outer peripheral surface of the entrance header 2 (however, the entrance header 2 Is larger than the inner peripheral surface of the). Other configurations and operations are the same as those in the first and second embodiments.

Next, a fourth embodiment of the present invention shown in FIGS. 7 and 8 will be described. In the case of the present embodiment, after the plate piece 9 is inserted into the insertion hole 8, the outer peripheral opening of the insertion hole 8 is
The gap between the outer peripheral edge of the arc plate 15 and the outer peripheral surface of the entrance-side header 2 is closed by welding. Arc plate 1
5 may be fixed to the outer peripheral edge of the large-diameter-side semicircular arc portion 11 of the plate piece 9 in advance. Other configurations and operations are the same as those in the first, second, and third embodiments.

[0029]

The method for manufacturing an aluminum heat exchanger according to the present invention is constructed and operated as described above, but a sufficient amount of brazing material is interposed in the partition wall installation portion to seal the partition wall installation portion. This ensures that the aluminum heat exchanger performs as specified. In addition, even if the gap between the brazing portions is somewhat large, reliable brazing can be performed, so that it is not necessary to restrict the dimensional accuracy and assembling accuracy of the constituent parts very strictly, and the production cost of the aluminum heat exchanger is reduced. Can be reduced.

[Brief description of the drawings]

FIG. 1 is a front view of a main part showing a first embodiment of the present invention.

FIG. 2 is a sectional view taken along line AA of FIG.

FIG. 3 is a side view of a main part showing a second embodiment of the present invention.

FIG. 4 is a sectional view taken along line BB of FIG. 3;

FIG. 5 is a side view of a main part showing a third embodiment of the present invention.

FIG. 6 is a sectional view taken along the line CC of FIG. 5;

FIG. 7 is a side view of a main part showing a fourth embodiment of the present invention.

8 is a sectional view taken along the line DD of FIG. 7;

FIG. 9 is a front view showing an example of an aluminum heat exchanger to which the present invention is applied.

FIG. 10 is an exploded perspective view showing a partition forming portion in a conventional aluminum heat exchanger.

FIG. 11 is a cross-sectional view of a partition forming portion according to FIG. 10;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Inlet pipe 2 Inlet header 3 Outlet pipe 4 Outlet header 5 Heat transfer tube 6 Fin 7 Partition wall 8 Insertion hole 9 Plate piece 10 Small diameter side semi-arc part 11 Large diameter side semi-arc part 12 Step part 13 Core part 14 Gap 15 Arc Board

──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Tsutomu Sunaga 5-24-15 Minamidai, Nakano-ku, Tokyo Calsonic Corporation (72) Inventor Makoto Negishi 5-24-15 Minamidai, Nakano-ku, Tokyo Cal Sonic Incorporation (56) References Japanese Utility Model Sho 64-31368 (JP, U) Japanese Utility Model Sho 63-30789 (JP, U) Japanese Utility Model Sho 63-173689 (JP, U) Japanese Utility Model Sho 56-39912 (JP, U.S.A.) Y2) The Japan Society of Mechanical Engineers, edited by the Japan Society of Mechanical Engineers, “Mechanical Engineering Handbook [Vol. 17] Machining,” 6th revised edition, The Japan Society of Mechanical Engineers, May 1978, p. 86-88 (58) Fields surveyed (Int. Cl. ⁷ , DB name) B28F 9/00-9/02

Claims (1)

(57) [Claims] 1. A pair of aluminum headers spaced apart from each other, a plurality of aluminum heat transfer tubes having both ends passing through both headers, and a space between adjacent heat transfer tubes. A method for manufacturing an aluminum heat exchanger, comprising: an aluminum fin sandwiched between; and an aluminum partition provided at an intermediate portion of at least one of the headers and dividing the inside of the header into a plurality of chambers,
When configuring the above partition, laminating a core material and a brazing material
A core material is inserted into a slit-shaped insertion hole formed on the side surface of the header on which the partition wall is to be provided , which is made of a clad material.
After inserting a plate piece configured to cover the inner cross section of the header by a clad material formed by laminating a brazing material ,
At least most of the gap between this plate piece and the inner peripheral edge of the insertion hole is closed by welding, and then the components of the aluminum heat exchanger are heated in a temporarily assembled state,
A method for manufacturing an aluminum heat exchanger, in which the components are brazed and joined, and at the same time, the space between the plate piece and the header is brazed in a liquid-tight manner.