JPH0894275A - Tube element for heat exchanger and heat exchanger having the same, and method for making heat exchanger - Google Patents

Abstract

PURPOSE: To provide a tube element for a heat exchanger capable of being manufactured of a common formed plate, to provide a heat exchanger capable of being provided with an improved heat exchanging efficiency by using the tube element for the heat exchanger and to provide a method for manufacturing the heat exchanger wherein brazing strength is increased by using the tube element for the heat exchanger. CONSTITUTION: A protrusion 22b and a hole 22c formed in the protrusion 22b have common opposing walls. When the opposing walls are respectively constituted of formed plates 22a1, 22a2, the plates 22a1, 22a2 are formed by using common dies. To make the hole 22c in the formed plates 22a1, 22a2, a perforating punch can be used to perforate instead of using a press working so that no chips are created.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a heat exchanger used in a vehicle air conditioner and a method for manufacturing the heat exchanger,
Furthermore, the present invention relates to a heat exchange tube element that constitutes this heat exchanger.

[0002]

2. Description of the Related Art Conventionally, as this type of heat exchanger, one disclosed in Japanese Patent Laid-Open No. 20794/1992 has been proposed.

In this heat exchanger, a press-formed hole is formed in the projecting portion of one of the opposing molding plates, and a projection that fits into this hole is formed in the projecting portion of the other molding plate. Temporarily assemble each molded plate through the protrusions and holes,
It is to be brazed.

According to this method of manufacturing the heat exchanger, the portion between the hole and the protrusion also serves as a brazing portion, and the brazing portion is enlarged, so that the flux is applied from the outside of the heat exchange tube element. Even by itself, sufficient brazing strength can be obtained.

[0005]

However, in the above-mentioned conventional heat exchanger, one of the molding plates has a hole formed therein and the other has a protrusion formed therein, which are different in shape from each other. However, there is a problem in that two types are required, resulting in an increase in manufacturing cost.

In this heat exchanger, air flows through the fins, but since the adjacent fins are partitioned by the heat exchange tube element, air flows between the fins. There is nothing to do. For this reason,
The wind pressure of each fin may differ between each fin depending on the wind direction, etc., but in such a situation, there is a problem in that the amount of air passing through each fin varies and uniform heat exchange cannot be performed. Was.

In view of the conventional problems described above, an object of the present invention is to provide a heat exchange tube element which can be manufactured with a common molding plate, and the heat exchange efficiency is improved by using this heat exchange tube element. (EN) It is an object to provide a heat exchanger, and further to provide a method for manufacturing a heat exchanger that improves brazing strength by using this tube element for heat exchange.

[0008]

According to the inventions of claims 1 and 4, the projecting portion and the hole formed in the projecting portion are common to the opposing walls. When each is formed by each forming plate, this forming plate can be formed by a common mold. In addition, claim 4
In the invention of (1), when punching a hole in the protruding portion, the punch or the like is simply formed without penetrating, so that no chips are generated.

According to the second and fifth aspects of the invention, since the adjacent fins communicate with each other through the holes formed in the facing wall, the air passing through the fin portions mutually flows through the holes, and the fin portions are communicated with each other. Make the wind pressure uniform.

According to the third and sixth aspects of the present invention, since the joint portion of the protrusion is exposed to the outside through the hole, the flux and the brazing material flow around the joint portion through the hole, and the joint portion is brazed. Used as. Further, in the invention of claim 6, since the protruding portion is formed around the hole, the brazing material is collected in the protruding portion, and the brazing strength is improved.

[0011]

1 to 17 show one embodiment of a heat exchange tube element, a heat exchanger and a method of manufacturing the heat exchanger to which the present invention is applied. FIG. FIG. 2 is a perspective view of a heat exchanger used as a condenser for air conditioning (hereinafter referred to as a first heat exchanger), and FIG. 2 is a heat exchanger used as an evaporator for vehicle air conditioning (hereinafter referred to as a second heat exchanger). ) Is a front view of FIG.

First, the first heat exchanger 10 shown in FIG. 1 has a pair of header pipes 11a and 11b facing each other, and
A plurality of tube elements 12 for heat exchange which penetrates this
A plurality of (hereinafter referred to as tubes 12) are arranged at intervals in the vertical direction, and fins 13 for heat exchange are interposed between the tubes 12. A partition plate 11c is provided on each of the header pipes 11a and 11b so that the refrigerant flowing in the heat exchanger 10 is made to meander.

According to the first heat exchanger 10, as shown in FIG. 3, the discharge refrigerant flows from the compressor (not shown) through the refrigerant supply pipe 14 of the one header pipe 11a, and the discharge refrigerant meanders from above. It flows downward and is fed to an expansion valve (not shown) through the refrigerant outflow pipe 15 of the other header pipe 11b. A heat medium for heat exchange, for example, air is passed through the fins 13 and heat is exchanged between the air and the refrigerant in the tube 12.

On the other hand, the second heat exchanger 20 shown in FIG. 2 includes a tank 21 before and after the refrigerant is branched or collected, and a plurality of heat exchange tube elements 22 (hereinafter, referred to as tank elements) penetrating the tank 21.
Tube 22) and a plurality of fins 23 through which air for heat exchange flows.
And are alternately laminated. Further, the one tank 21 is divided into left and right by a partition 21a.

According to the second heat exchanger 20, as shown in FIG. 4, the refrigerant decompressed by the expansion valve enters the suction portion 21b of the tank 21 in the front through the refrigerant feed pipe 24,
It flows into the tank 21 on the rear side through the tube 22 facing the suction portion 21b. The refrigerant further flows from the tank 21 on the rear side to the tube 22 facing the outflow portion 21c, collects in the outflow portion 21c, and circulates to the compressor through the refrigerant outflow pipe 25. On the other hand, a heat medium for heat exchange, such as air, passes through the fins 23, and heat is exchanged between the air and the refrigerant in the tubes 22.

The tubes 12 and 22 of the first heat exchanger 10 and the second heat exchanger 20 thus constructed are made of aluminum, aluminum alloy or the like because of their workability and thermal conductivity. It is configured as shown in FIGS. 6 and 7.

First, the tube 12 of the first heat exchanger 10 will be described with reference to FIG. This tube 12 is shown in FIG.
As shown in (a), the flat plate 12a has projecting portions 12b symmetrically with respect to the center in the width direction, and a hole 12c is formed at the center of the tip of the projecting portion 12b. The flat plate 12a having the protruding portion 12b and the hole 12c is bent from the center in the width direction into a flat tubular shape as shown by the one-dot chain line arrow in (a) of FIG. 5, and as shown in (b) of FIG. The tube 12 is formed.

On the other hand, the tube 22 of the second heat exchanger 20 has a pair of left and right molding plates 2 as shown in FIGS.
2a1 and 22a2, and the molding plates 22a1 and 2a
2a2 has a large number of protrusions 2 each having the same arrangement and shape.
2b is formed, and a hole 22c is formed at the center of the tip of the protrusion 22b. As shown in FIG. 7, the flat plates 22 are formed by stacking the molding plates 22a1 and 22a2 configured as described above so that the projections 22b thereof are joined.

The protrusions 12b (22b) and the holes 1 of the first heat exchanger 10 and the second heat exchanger 20 configured as described above.
2c (22c) is manufactured by the common method shown in FIGS. 8 (a) (b) (c).

That is, as shown in FIG. 8A, the flat plate 12a or the molding plates 22a1 and 22a2 are composed of a lower mold 30 protruding upward and an upper mold 31 having a recess corresponding to the protruding portion. Between the plates 12a (22a1,
22a2) and the plate 12a (22a1, 22a
2) is embossed to form a large number of protrusions 12b (22b).

When the embossing process is completed, the upper and lower molds 32 and 33 having the punch through holes 32a and 33a are formed.
The protrusion 12b (22b) is positioned between the two, and then the punching punch 34 is moved in the direction opposite to the protrusion direction of the protrusion 12b (22b) to pierce and penetrate the protrusion 12b (22b). As a result, the hole 12c (22c) having the protruding portion A is formed as shown in FIG. 8 (c).

When this drilling process is completed, the projecting height of the projecting portion 12b (22b) is somewhat lowered in this drilling process, so press working to correct this is performed as shown in FIG. 8 (c). Is desirable. That is, the protrusion 12b (2
2b) the upper mold 35 corresponding to the outer surface, and the protrusion 12b.
The protrusion 12b (22b) is arranged between the lower mold 36 and the lower die 36 that pushes up the inside of (22b), and is pressed. This allows
The protrusion height of the protrusion 12b (22b) is corrected to a desired dimension. It should be noted that this correction press work becomes unnecessary when the projection height and the like are set in consideration of this correction value in the embossing process and the like.

The tube 12 (22) is formed in this manner, and each component of the heat exchanger 10 (20) including this tube 12 (22) is temporarily assembled and then brazed. In the temporary assembly process, first, the temporary assembly process of the first heat exchanger 10 will be described with reference to FIGS. 9 and 10.

First, a temporary assembling jig for temporarily assembling the first heat exchanger 10 is prepared. This temporary assembly jig has a vertically extending support rod 50. A fixed tongue piece 51 is fixed near the lower end of the support rod 50 and penetrates through the support rod 50 near the upper end to move vertically. The tongue piece 52 is attached. Two such support rods 50 are prepared and the support rods 5
In addition to 0, two horizontally long rectangular tubular contact members 53 are prepared as temporary assembly jigs.

On the other hand, on the heat exchanger 10 side, a plurality of tubes 12 are arranged at intervals between the header pipes 11a and 11b facing each other on the left and right, and both ends of each tube 12 are inserted into the header pipes 11a and 11b. Temporarily fix. Further, in the tube 12, above the tube 12 located at the top and below the tube located at the bottom, side plates 16 for reinforcement are arranged at intervals from the tube 12, respectively. Both ends of 16 are similarly inserted into the header pipes 11a and 11b and temporarily fixed. When the temporary fixing of the tubes 12 and the side plates 16 is completed, the tubes 1 vertically adjacent to each other
Fins 13 are interposed between the two and between the tube 12 and each side plate 16. The header pipe 11a,
The upper and lower caps 11d, the partition plate 11c, the refrigerant supply pipe 14, and the refrigerant outflow pipe 15 of 11b are temporarily fixed in advance to the header pipes 11a and 11b, respectively.

Such a temporary assembling jig and the temporarily assembled first
When the heat exchanger 10 is prepared, first, the contact members 53 are fitted to the upper and lower side plates 16 of the first heat exchanger 10, respectively. Next, the support rods 50 are arranged on the left and right so as to support both ends of the first heat exchanger 10, and
The first heat exchanger 10 via the fixed tongue piece 5 of the support rod 50.
Place on top of 1. As a result, the temporarily assembled first heat exchanger 10 is supported on the support rod 50. Then, as shown in FIG. 9, the movable tongue piece 52 is shifted downward to move the movable tongue piece 52.
The 1st heat exchanger 10 is hold | maintained between and the fixed tongue piece 51.
As a result, the temporarily assembled first heat exchanger 10 is fixed by the temporary assembly jig as shown in FIG.

Next, the temporary assembly process of the second heat exchanger 20 will be described with reference to FIG.
The description will be made with reference to FIGS.

First, a temporary assembling jig for temporarily assembling the second heat exchanger 20 is prepared. This temporary assembly jig has a pair of parallel connecting rods 65 extending left and right in the front and rear direction, and has a rectangular support frame 61 in which both ends thereof are connected by prismatic fixing metal fittings 62 and 64, respectively. Also, one of the fixing brackets 6
A female screw is engraved in the center of the screw 4, and a T-shaped bolt 63 is screwed into this female screw. As shown in FIG. 12, the T-shaped bolt 63 has a shaft 63a that penetrates in a state in which the shaft 63a is screwed into the fixing metal fitting 64, while the end of the shaft 63a is flat. When turning
It moves in the left-right direction as shown by the arrow in FIG. Two such support frames 61 are prepared up and down, and in addition to the support frames 61, two vertically long bracket-shaped pressing plates 60 are prepared as temporary assembly jigs.

On the other hand, the second heat exchanger 20 includes the tube 2
A plurality of 2 are arranged with a space left and right, a tank 21 is arranged at the upper and lower ends of each tube 22, and the tube 22 and the tank 21 are temporarily fixed in a communicating state. In addition, the side plates 26 are arranged on both left and right sides of the tubes 22, and the fins 2 are provided between the adjacent tubes 22 and between the tubes 22 and the side plates 26.
Interpose 3. When the fins 23 are interposed, the molded plates 22a1 and 22a2 of the tube 22 have bent portions 22d1 and 22d2, and the bent portions 22d1 and 22d1
22d2 prevents the fins 23 from falling out from between the tubes 22. The partition plate 21a, the refrigerant supply pipe 24, and the refrigerant outflow pipe 25 are temporarily fixed to the tank 21 in advance.

Such a temporary assembling jig and the temporarily assembled second
When the heat exchanger 20 is ready, the T-shaped bolts 63 of the two support frames 61 are rotated to make a large storage space for the temporarily assembled second heat exchanger 20. Next, the two support frames 61 are vertically arranged in the approximate center of the second heat exchanger 20, and the second heat exchanger 20 is housed in the support frame 61. Then, the holding plate 60 is inserted between the side plate 26 of the second heat exchanger 20 and the fixing fittings 62, 64. After a while
The T-shaped bolt 63 is rotated to hold the second heat exchanger 20 between the two holding plates 60. As a result, the temporary assembly of the second heat exchanger 20 is completed as shown in FIG.

When the temporary assembly of the first heat exchanger 10 and the second heat exchanger 20 is completed, the common brazing process shown in FIGS. 14A and 14B is performed.

That is, in this brazing process, first, from the outside of the heat exchanger 10 (20) including the tubes 12 (22) and the fins 13 (23), as shown in FIG. Apply 40.

As a method of applying this flux, 4% to 1
A method of spraying an aqueous solution or alcohol solution of 0% flux, a method of electrostatically applying a powdery flux, or a method of simply applying a powdery flux without charging the heat exchanger 10 (20). However, there is a method of electrostatically applying a powdery flux or a method of applying a powdery flux without being charged because of the implication of omitting the drying step and the subsequent brazing conditions. desirable.

When the flux applying step is completed, the heat exchanger 10 (20) temporarily assembled is brazed in an inert gas. Thereby, the protrusion 12b (2
2b) butted part is brazed.
As shown in (b), a large amount of the fillet 41 is formed on the peripheral edge of the abutting portion, particularly on the protruding portion A of the hole 12c (22c).

As described above, according to this embodiment, in the tube 12 (22), the hole 1 formed at the time of manufacturing the tube 12 (22).
Since 2c (22c) is not press sheared and the punching punch 34 is simply formed by piercing the protruding portion 12b (22b), chips are not generated and an air mechanism is not required.

Further, since the projecting portions 22b and the holes 22c of the molding plates 22a1 and 22a2 forming the tube 22 have the same arrangement and shape, the molding plates 22a1 and 22a2 can be commonly used, and the molding can be easily performed. Become.

In the heat exchanger 10 (20) constructed by using the tube 12 (22), the tube 12
Air passing through the adjacent fins 13 (23) with (22) in between flows through the holes 12c (22c), and each fin 1
The wind pressure in the area 3 (23) becomes uniform.

In the method of manufacturing the heat exchanger 10 (20) constructed by using the tube 12 (22), the hole 1
The flux 40 is protruded through the 2c (22c) 12b.
(22b) is applied to the abutted portion to enlarge the brazing portion, and the fillet 41 is attached to the overhanging portion A.
Since a large amount is formed, the brazing strength can be sufficiently secured without applying the flux 40 to the inside of the tube 12 (22).

Also, in this way, the protrusion 12b (22b)
Since the abutting portion of the tube is surely brazed, the strength of the tube 12 (22) is improved so that the tube is not damaged by the pressure of the refrigerant, and the protruding portion 12b should not be damaged.
Even if the abutting portion of (22b) is not brazed reliably, the abutting portion with a defective joint can be surely found by the leak inspection in advance.

Although the protrusion 22b is formed in a circular shape in the above embodiment, as shown in FIG. 15 (a), it is formed in a long groove-shaped protrusion 22b1 or a triangular protrusion 22b2. Alternatively, the holes 22c may be provided at a plurality of positions. In addition, as shown in FIG. 15 (b), the elongated hole 22 that has pierced along this groove is formed in the elongated groove-like protruding portion 22b1.
The molding plate 22a1 (22a2) may be provided with the protrusion 22b and the hole 22c in the partition 22d.

Further, although the flat plate 12a is bent to form the flat tube 12 in the embodiment of the first heat exchanger 10, as shown in FIG. 16, it has a protrusion 12b and a hole 12c. Alternatively, the flat plates 12d1 and 12d2 may be formed, and the flat plates 12d1 and 12d2 may be opposed to each other and brazed. In addition, in the embodiment of the second heat exchanger 20, a pair of molding plates 22a is formed.
1, 22a2 are prepared in advance and are joined to face each other to form the tube 22, but as shown in FIG.
Forming plates 22a1, 22 having 2b and holes 22c
The tube 22 may be formed by connecting and forming a2, bending the connecting portion, and superposing the molding plates 22a1 and 22a2.

FIGS. 18 (a) and 18 (b) and FIGS. 19 (a) and 19 (b) show another embodiment of the present invention. Similar to the tube 22, the tube 72 according to this embodiment has a pair of left and right molding plates 72a1 and 72a2 having projecting portions 72b formed therein, and the projecting portions 72b having holes 72c formed therein. As shown in FIGS. 18 (a) and 18 (b), the tip 72b1 of the protrusion 72b is formed flat and
The tube 72 differs from the tube 22 in that the hole 72c formed in the flat tip 72b1 is formed flush with the tip 72b1.

When manufacturing the protrusion 72b and the hole 72c as described above, as shown in FIG. 19 (a), the molding plates 72a1 and 72a2 are formed in the same manner as in the tube 22, as shown in FIG.
As shown in FIG. 9 (a), the molding plate 72a1 (72a2) is disposed between the lower mold 30 protruding upward and the upper mold 31 having a recess corresponding to the protruding portion. (22a2) is embossed, tip 72b
1 forms a large number of flat protrusions 72b.

When the embossing process is completed, the projecting portion 72b is positioned between the upper and lower molds 32 and 33, and then the press punch 37 is penetrated through the center of the tip 72b1 of the projecting portion 72b to perform the drilling process. . As a result,
The tube 72 as shown in (a) and (b) of 8 is manufactured.

According to the present embodiment, unlike the above-mentioned embodiment, it is not possible to prevent the generation of chips, but the manufacturing process is very simple, and the molding plates 72a1 and 72a2 are made. The flux A applied to the outer surface also wraps around the inside of the hole 72c as shown in FIG. 18 (a), and after brazing in an inert gas, a large amount of fillet 41 is formed at the abutting portion. The brazing strength is high.

In this embodiment, the adhesion amount of the flux 40 is 3 g / m ³ or more. Further, the tube 72 according to the present embodiment is temporarily assembled as the second heat exchanger 20 by the same method as the tube 22, and is brazed by the same method.

[0047]

As described above, according to the first and fourth aspects of the invention, the projecting portion and the hole formed in the projecting portion are common to the opposing walls. When configuring the facing wall with each molded plate,
Since this molding plate can be molded with a common mold, the manufacturing cost is reduced. Further, according to the invention of claim 4, when a hole is formed in the protruding portion, it is formed by simply piercing without punching. Therefore, a chip is not generated, and an air mechanism for blowing off the chip as in the conventional case is installed. Does not need

According to the second and fifth aspects of the present invention, since the adjacent fins are communicated with each other through the holes formed in the facing wall, the air passing through the fin portions mutually flows through the holes, and the fin portions are connected to each other. The air pressure can be made uniform, and the heat exchange efficiency of the entire heat exchanger can be improved.

According to the third and sixth aspects of the invention, since the joint portion of the protrusion is exposed to the outside through the hole, this joint portion can be used as a brazing portion and the brazing portion is enlarged. Further, in the invention of claim 6, since the projecting portion is formed around the hole, the brazing material is collected in the projecting portion, and the brazing strength is improved.

[Brief description of drawings]

FIG. 1 is a perspective view of a first heat exchanger.

FIG. 2 is a perspective view of a second heat exchanger.

FIG. 3 is an explanatory diagram showing a refrigerant flow in the first heat exchanger.

FIG. 4 is an explanatory diagram showing a refrigerant flow in a second heat exchanger.

FIG. 5 is a perspective view of a heat exchange tube element of the first heat exchanger.

FIG. 6 is a front view of a heat exchange tube element of the second heat exchanger.

FIG. 7 is a sectional view of a heat exchange tube element of the second heat exchanger.

FIG. 8 is a cross-sectional view showing a manufacturing process of a protrusion and a hole.

FIG. 9 is a perspective view showing a temporary assembly jig used for temporary assembly of the first heat exchanger.

FIG. 10 is a perspective view showing a state in which the first heat exchanger is held by a temporary assembly jig.

FIG. 11 is a perspective view showing a temporary assembly jig used for temporary assembly of the second heat exchanger.

FIG. 12 is a partially cutaway plan view of a temporary assembly jig for the second heat exchanger.

FIG. 13 is a perspective view showing a state where the second heat exchanger is held by a temporary assembly jig.

FIG. 14 is a cross-sectional view showing a flux applying process and a brazing process.

FIG. 15 is an abbreviated front view showing a modified example of protrusions and holes.

FIG. 16 is a perspective view showing another manufacturing process of the tube of the first heat exchanger.

FIG. 17 is a front view showing another manufacturing process of the tube of the second heat exchanger.

FIG. 18 is a cross-sectional view showing a flux applying step and a brazing step according to another embodiment.

FIG. 19 is a cross-sectional view showing a process of manufacturing a protrusion and a hole according to another embodiment.

[Explanation of symbols]

10, 20 ... Heat exchanger, 12, 22, 72 ... Heat exchange tube element, 12a ... Flat plate, 12b, 22
b, 72b ... Projection, 12c, 22c, 72c ... Hole, 1
3, 23 ... Fins, 34 ... Punch for punching, 40 ... Flux, A ... Overhang part.

Claims (6)

[Claims] 1. A heat exchange tube element, which is formed in a flat tubular shape and has a large number of protrusions formed on its opposing wall toward the opposing surface, and the tips of the opposing protrusions are butted against each other and joined together. The heat exchanging tube element, wherein the tip of each of the projections is formed flat, and each projection has a hole substantially flush with the tip. 2. A heat exchanger characterized in that the heat exchange tube element according to claim 1 through which a refrigerant passes and fins for heat exchange through which a medium such as air passes are alternately stacked. 3. The heat exchange tube element and the fin of claim 2 are temporarily assembled, and then a non-corrosive flux is applied from the outside of the heat exchange tube element and the fin, and then in an inert gas. A method for manufacturing a heat exchanger characterized by being attached. 4. A heat exchange tube element, which is formed in a flat tubular shape and has a large number of protrusions formed on its opposing wall toward the opposing surface, and the tips of the opposing protrusions are butted against each other and joined together. A tube element for heat exchange, characterized in that it has a hole formed at the tip end thereof in a direction opposite to the projecting direction to form a projecting portion. 5. A heat exchanger characterized in that the heat exchange tube elements of claim 4 through which the refrigerant passes and the heat exchange fins through which a medium such as air passes are alternately stacked. 6. The heat exchange tube elements and fins according to claim 5 are alternately laminated and tentatively assembled, and then a non-corrosive flux is applied from the outside of the heat exchange tube elements and fins. A method for manufacturing a heat exchanger, characterized by brazing in an inert gas.