JPH03184645A - Heat exchanger fin and its manufacture - Google Patents

Abstract

PURPOSE:To improve efficiency of heat radiation and to miniaturize a heat exchanger by forming projecting parts and recessed parts alternately on both long edge collars of a flat through hole having a collars, folding only the tip parts of the projecting parts and forming flat parts parallel and on a level with a metallic sheet body. CONSTITUTION:A flat through hole 2 is formed on a metallic sheet 1 and collars nearly vertical to the sheet 1 is formed all over the edge of the flat through hole. The projecting part A and the recessed part B are formed alternately on these collars 3, 3 and the projecting part A and the recessed part B are formed on the position facing each other. The flat parts 5 which are folded on the outside of the flat through hole 2 and substantially parallel with the metallic sheet body are formed intermittently on the upper part of the projecting part A. These flat parts 5 come in contact with other fins to position them in a heat exchanger and the levels of the flat parts are made up so that they are nearly equal. Consequently, this fin can be used suitably for a flat heat exchanger excellent in the efficiency of heat radiation.

Description

Detailed Description of the Invention (Industrial Application Field) The present invention relates to a heat exchanger fin and a method for manufacturing the same, and more particularly to a heat exchanger fin used in a heat exchanger such as a household cooler or an automobile cooler. and its manufacturing method.

(Prior art) Cooling fins used in the heat radiating part of heat exchangers such as automobile coolers or household coolers are made by attaching a plurality of collars of a predetermined height to a rectangular metal plate such as a thin aluminum plate. The holes are scored.

A heat exchanger formed by such fins is constructed by polymerizing a plurality of fins with the collared through holes of each fin matching each other, and using a metal with high thermal conductivity such as copper to cover the through holes. A heat exchange tube is inserted and integrated.

By the way, in recent years, along with the miniaturization of rivers, heat exchangers are also becoming smaller.

With the miniaturization of such heat exchangers, it is necessary to increase the heat exchange efficiency of heat exchange tubes.

In particular, as the use of fluorocarbon gas, which is a refrigerant with good heat exchange efficiency, has recently become restricted, there is a need to further increase the heat exchange efficiency.

For this reason, flat cooling tubes with a flat cross-sectional shape, which can provide a larger heat transfer area than circular cooling tubes with a circular cross-sectional shape, are being used.

The fins of a heat exchanger constituted by such heat exchange tubes having a flat cross-sectional shape are formed with collared through holes as shown in FIG. 7.

Such a through hole is a rectangular (hereinafter sometimes referred to as a flat shape) through hole 102 in a thin metal plate 100 made of aluminum or the like.
are formed, and collars 104 and 104 that are substantially perpendicular to the metal 1g1oo are formed on both long edges of the through hole 102.

Further, near the through hole 102, picos 106, 106 are provided. This pico 106.106 is formed so that its height is higher than the collar 104.104, and is used to position the other fin by coming into contact with the other fin when polymerizing the fins. be.

The flat collared through hole shown in FIG. 7 is formed by the method shown in FIG.

First, as shown in Figure 8 (I), small holes 10 are made in a thin metal plate.
8.108 is within the planned through hole formation (-within the range surrounded by the dotted chain line)
After forming the small holes 108, 108 to face each other, a linear cut 110 is formed between the small holes 108 and 108.

Next, an elongation process (burring) is performed using a punch and die of the size of the through hole to be formed, and collars 104, 104 are formed on the through hole and both long edges of the through hole.The collars 104, 104 to be formed are as follows: As shown in FIG. 8 (II>), it is approximately perpendicular to the thin metal plate.

Furthermore, picos 106 and 106 are formed near the through hole 102.

(Problem to be Solved by the Invention) The contact area between the flat collared through hole and the flat heat exchange tube shown in FIG. Since the contact area can be made large compared to the contact area, heat transfer efficiency can be improved.

However, when trying to increase the density of the through holes in order to downsize the heat exchanger, etc., the presence of pico, which hardly participates in heat transfer between the heat exchange tube and the fins, makes it difficult to increase the density of the through holes. has its limits.

Furthermore, recently, in order to further improve the heat transfer efficiency of the fins, slits, etc. have been formed between the through holes, but Pico has is also becoming an obstacle.

Further, since the step of forming pico is essential in the fin manufacturing process, the fin manufacturing efficiency is reduced.

Therefore, the present invention provides a fin in which a rectangular collared transparent hole (hereinafter sometimes referred to as a collared flat transparent hole) is formed, in which the fin can be positioned without forming a pico, and the manufacturing efficiency is improved. An object of the present invention is to provide a fin for a heat exchanger and a method for manufacturing the same, which can improve the performance of the heat exchanger.

(Means for Solving the Problem) In order to achieve the above object, the present inventor formed a concave portion and a convex portion in the collars on both long edges of a flat transparent hole with a collar, and positioned the fin at the tip of the convex portion instead of the pico. When we tried to do this, we found that although it was possible to make the height of the tip of the protrusion equivalent to a pico, it could not be used for positioning the fin. This is to get into the hole.

As a result of further studies based on the above knowledge, the present inventor found that by bending the tip of the convex part, it is possible to prevent the tip of the convex part from entering the through hole of the other fin and to determine the inside position. , arrived at the present invention.

That is, in the present invention, a plurality of rectangular through holes into which heat exchange tubes of a heat exchanger are inserted are formed in a metal plate, and a hole is formed along the circumferential edge of the through hole substantially perpendicular to the metal plate. A fin for a heat exchanger in which collars are formed facing each other, and in which concave portions and convex portions are alternately formed on the protruding edge portion of the collar, and four portions and a convex portion formed on the protruding edge portion. are located opposite to each other, and the tips of each of the convex portions are bent toward the outside of the through hole to form a flat portion that is substantially parallel to the metal plate-like body and has a height that is slightly open. The heat exchanger fin is characterized by:

In addition, between two small holes or small cuts formed opposite to each other in the metal plate, at least some of the lines connecting the centers of the two small holes or small cuts alternately intersect with each other in a zigzag shape. After forming a meandering cut, the small hole or small cut and the zigzag cut are processed to protrude, and the rectangular through hole and the long edge of the through hole are approximately perpendicular to the metal plate. A collar is obtained, and then the tip of the convex part of the collar is pressed and bent toward the outside of the through hole to form a flat part that is substantially parallel to the metal plate and has a height that is slightly open. This is a method for manufacturing heat exchanger fins.

(Function) According to the present invention, concave portions and convex portions are alternately formed on the collar of the circumferential edge of the flat transparent hole with a collar, and only the tips of the convex portions are bent, so that the collar is substantially parallel to the metal plate-like body and at the same time. Open-height flat portions are formed intermittently in the longitudinal direction of the collar.

Therefore, the flat part formed at the tip of the convex part of the collar is higher than the collar height of the conventional through-hole with a collar, and can prevent the other fin from entering the through-hole. Pico can be made unnecessary.

Further, since it is not necessary to form a pico, the fin manufacturing process can be simplified, and the fin manufacturing efficiency can be improved.

(Example) The present invention will be explained in more detail using the drawings.

FIG. 1 is a perspective view and a sectional view showing an embodiment of the present invention.

In FIG. 1(a), a flat through hole 2 is formed in a thin metal plate 1, and a collar is formed over the gold edge of the flat through hole 2, which is substantially perpendicular to the thin plate l.

Among these collars, the collar 3.3 formed on the circumferential long edge of the flat through hole 2 is taller than the collars formed on both edges of the flat through hole 2 in the short axis direction.

Furthermore, protrusions A and recesses B are formed alternately on each of the collars 3.3, and protrusions A and recesses B are formed on both edges of the collar.
are formed at positions facing each other.

In addition, at the upper part of the convex part A, as shown in FIG. 1(b), which is a cross-sectional view of the XX plane in FIG. 1(a), a metal plate shaped Flat portions 4 substantially parallel to the body 1 are formed intermittently.

This flat portion 4 abuts against other fins in the heat exchanger to position the fins.
4... is formed so that the height between the openings becomes -.

The collared flat transparent hole of this embodiment shown in FIG.
It can be manufactured by the steps shown in FIG.

First, a small hole 8.8 was made in a thin metal plate [Fig. 2 (I)
], cuts 10 are formed between the small holes 8.8, which meander in a zigzag shape with an amplitude while alternately intersecting the straight line connecting the centers of the small holes 8.8 [FIG. 2 (II)].

Incidentally, the amplitude of the cut lO is set to be equal to or less than the short axis length of the flat through hole to be formed.

Next, the cut 10 and the small hole 8.8 are burred using a punch and die in the shape of the collared through hole to be formed,
Form a flat through hole 2 [Fig. 2 (1)].

A collar that is substantially perpendicular to the thin metal plate is formed on the gold edge of the flat through-hole 2 that is formed.

During this burring process, ironing process (ironing process) is used to further increase the height of the color obtained.
may be applied.

The side surface state of the flat transparent hole 2 [in the direction of arrow E in FIG. 2 (III) [110 is shown in FIG. is shown in Figure 3 (
As shown in a), convex portions A and concave portions B are formed alternately.

Further, a convex portion A is formed at a position of the other collar 3 opposite to a concave portion B formed on one side of the collar 3, and a convex portion A is formed at a position of the other collar 3 opposite to a convex portion A formed on one side of the collar 3. A recess B is formed in.

Here, for example, assume that the minor axis length W of the collared transparent hole to be formed in a metal plate with a thickness of 0.1 mm is 2 mm, and the amplitude of the cut 10 between the small holes 8 and 8 to be drilled is 15 W. , the maximum height of the color that can be obtained only by burring is 1
．． 5-m, and when combined with 35% ironing, the maximum height is approximately 2.4 meters (plate thickness approximately 0.07 mm).
mm) can be obtained.

On the other hand, as in the conventional method shown in FIG.
．． When a linear cut is formed between the holes 108 and 108, the height of the collar obtained by burring is at most 1 - in the case of forming a flat through hole with a minor axis length of 2 lobes.

In addition, in the conventional method, ironing processing was not performed after burring.

The flat transparent hole with collar shown in FIG. 2 (III) and FIG. Flat portions 4.4 parallel to are intermittently formed along the circumferential edge of the flat through hole 2 [FIG. 2 (IV)].

The flat through hole 2 in which such a flat portion 4 is formed is shown in FIG.
The side view of [V] in the direction of arrow F is shown in FIG. 3(b).

As is clear from FIG. 3(b), the flat portion 4 constitutes a part of a bent portion formed by bending the tip of the convex portion A toward the outside of the flat transparent hole 2.

By forming the flat portions 4 intermittently in the longitudinal direction of the collar 3 as in this embodiment, it is possible to avoid a situation where the entire collar is tilted when pressing the collar to form the flat portions 4. can.

The degree of bending of this bent portion can be adjusted as appropriate depending on the required gap between the fins when the fins are superposed.

The fin of this example can be obtained using the apparatus shown in FIG.

The apparatus shown in FIG. 4 and the process shown in FIG. 2 will be explained in correspondence with each other.

The process of drilling the small hole 8.8 in Figure 2 (I) is shown in Figure 4 (a).
Perform with the equipment shown in.

This mold consists of a drilling punch 15 and a drilling die 16 fixed to an upper base 11 and a lower base 14,
Two small holes 8.8 are bored in the thin metal plate 1 placed on the upper surface of the lower base 30.

Next, after confirming the position of the small hole 8.8 using the pilot 18 shown in FIG. 4(b), which has a needle-like object at the tip, the small hole 8.8 is cut using the cutter shown in FIG. 4(c). A cut 10 (not shown in FIG. 2(II)) is formed in between.

This cutter consists of an upper blade 24 and a lower blade 26 that are fixed to an upper mounting plate 20 and a lower mounting plate 22, and the tip of the cutting blade is formed to match the curve of the cut 10.

The process shown in FIG. 2 (III) for burring the small hole 8.8 and the cut 10 thus formed can be performed using the burring punch 34 and die 32 shown in FIG. 4 (d).

The burring punch 34 and the die 32 are fixed to the upper mount 28 and the lower mount 30, and the tip of the die 32 and the cross-sectional shape of the die 34 have the shape of the through hole 2 to be formed.

By adjusting the gap between the inner wall surface of the die 32 and the tip wall surface of the punch 34, it is possible to iron the burred collar.
The height of the convex portion of the resulting collar can be further increased.

The process shown in FIG. 2 (IV) in which the collared flat through-hole shown in FIG. 3 (a) is flared can be carried out using the apparatus shown in FIG. 4 (e).

In this device, a flaring punch 40 is fixed to an upper table 36, and a die 38 is provided at the lower part.

The flaring punch 40 has grooves 42 and 44 on both ntq
The tips of the protrusions formed on the collar abut and bend at corners 42 and 44.

The series of devices shown in FIG.
They are arranged in series in the order shown in Figures (a) to (e), and Figure 4 (a)
) may be used to insert the thin metal plate 1.

Furthermore, by providing a plurality of lines in which the devices shown in FIG. 4 are arranged in series in the mold, a plurality of collared through holes can be formed in the thin metal plate l at the same time.

In this embodiment described above, when drilling the small hole 8.8, as shown in FIG. Although we have described the case in which the holes are provided, they may also be provided in contact with the flat through holes to be formed, as shown in FIG. 5(b).

However, in the case of Fig. 5(b), a part of the small hole 8.8 forms both short edges of the flat through hole, so it is not possible to form a collar around the entire circumference of the flat through hole. .

Moreover, the cut 10 formed between the small holes 8 and 8 is
．． It is sufficient that the cut is a meandering cut that alternately intersects the straight line connecting the centers of 8 and at least a part thereof, and the shape of the part beyond the straight line is rectangular [Fig. 6 (a)] or triangular [Fig. 6 (b)] ].

Furthermore, instead of the small holes 8.8 formed opposite to each other, small cuts in the shape of a semicircle or a cross may be used.

Note that the direction of the flat through-holes can be arbitrarily set in a direction that provides good thermal efficiency depending on the cooler used.

(Effects of the Invention) The heat exchanger fins of the present invention can be suitably used for flat heat exchange tubes with good heat transfer efficiency.

In addition, by eliminating the need for pico, the gap between the through holes can be narrowed, and slits can be provided between the through holes to increase heat transfer efficiency. It is also possible to effectively respond to miniaturization and fluorocarbon gas regulations.

[Brief explanation of drawings]

Fig. 1 is a perspective view and a sectional view showing one embodiment of the present invention, Figs. 2 and 3 are explanatory views explaining the manufacturing method of the 1 m flat transparent hole with collar shown in Fig. 1, and Fig. 4 is An explanatory diagram illustrating the apparatus used in the manufacturing method shown in FIGS. 2 and 3, FIGS. 5 and 6 are other embodiments, and FIG. 7 is a perspective view of a conventional flat transparent hole with a collar. and FIG. 8 are explanatory views for explaining a conventional method of manufacturing a flat transparent hole with a collar. In the figure, 1... metal thin plate, 2... flat through hole, 3... collar, 5... flat part, 8... small hole, 10... cut. A...convex part, B...four parts

Claims (1)

[Scope of Claims] 1. A plurality of rectangular through holes into which heat exchange tubes of a heat exchanger are inserted are formed in a metal plate, and the metal plate has a plurality of rectangular through holes formed along both long edges of the through holes. A fin for a heat exchanger in which substantially perpendicular collars are formed facing each other, and concave portions and convex portions are alternately formed on the protruding edge portion of the collar, and the protruding edge portion is formed on the protruding edge portion. A concave portion and a convex portion are located opposite to each other, and the tip of each of the convex portions is bent toward the outside of the through hole to form a flat surface substantially parallel to and at approximately the same height as the metal plate. A fin for a heat exchanger, characterized in that a fin is formed with a fin for a heat exchanger. 2. Between two small holes or small cuts formed opposite to each other in a metal plate, a zigzag pattern is formed, at least a part of which alternately intersects with a straight line connecting the centers of the two small holes or small cuts. After forming a meandering cut in the small hole or small cut,
and protruding zigzag cuts to obtain a rectangular through hole and a collar that is approximately perpendicular to the metal plate along the long edge of the through hole, and then press the tip of the convex part of the collar. A method for manufacturing a fin for a heat exchanger, characterized in that the fin is bent outward from a through hole to form a flat portion that is substantially parallel to and has approximately the same height as a metal plate.