JP2011089664A - Method of manufacturing corrugated fin for heat exchanger - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method of easily manufacturing a corrugated fin having high heat conductivity and high accuracy, with respect to the method of manufacturing the corrugated fin having a group of inclined grooves on a plane. <P>SOLUTION: A number of grooves 4a are continuously formed on the plane of a band-shaped metallic plate 3 in parallel with each other by a pair of rollers 1, 2, and their cross-sections are bent into a shallow waved plane. Then non-grooved sections 5 are formed in the width direction separately at constant intervals, and the metallic plate is folded at the positions of the non-grooved sections 5 to form folded sections 5a. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a method for manufacturing corrugated fins used in heat exchangers for construction, agriculture, and work machines that are used in an environment where dust and foreign matter are likely to be mixed with cooling air.

  A corrugated fin heat exchanger used in an environment in which foreign matter such as dust is likely to be mixed in a cooling airflow by a blower fan or the like cannot cut a louver to the corrugated fin. This is because clogging occurs in the cut and raised opening. In view of this, a structure in which a number of small grooves are formed on the plane of the corrugated fin has been proposed to promote heat exchange. Furthermore, what arrange | positioned each groove | channel inclined in the distribution direction of an airflow is proposed as the "regenerative heat exchanger and the regenerative heat exchange method" of the following patent document 1.

  This is a fin in which a large number of inclined grooves are arranged in a rectangular wave shape. In such a corrugated fin, due to the presence of a large number of inclined grooves, a swirling flow is generated when an air flow circulates therein, and heat exchange efficiency is improved.

Japanese Patent No. 3697523

In general, in order to form a corrugated fin having a large number of inclined grooves, a metal strip is supplied in the longitudinal direction between a pair of concave and convex grooved forming rolls.
Next, when the fin is bent into a wave shape and disposed between the flat tubes, there is an inconvenience that an inclined groove is present at the contact portion, so that the contact area is reduced and heat conductivity is deteriorated.
Therefore, the present invention aims to solve this problem and to maximize the heat exchange performance.

According to the present invention, the bent portion (5a) of the corrugated fin (8) contacts the flat outer surface of the parallel flat tubes (6), and the contact portion is brazed and fixed. A heat exchanger in which gas flows through the outer surface of the flat tube (6) and the corrugated fin (8), in the method for producing the corrugated fin for the heat exchanger,
A plurality of grooves (4a) are continuously formed in parallel on the plane of the belt-shaped metal plate (3) by a pair of forming rolls (1) and (2), and the transverse section is bent into a shallow corrugated plane;
Next, the shallow corrugated plane is spaced apart at regular intervals in the longitudinal direction of the strip-shaped metal plate (3), and the corrugated plane is flatly crushed to form a groove-free portion (5) in the width direction. And the step of folding back the band-shaped metal plate (3) at the position of the groove-free portion (5), and forming the bent portion (5a) there,
It is a manufacturing method of the corrugated fin for heat exchangers which comprises this.

The present invention according to claim 2 is the method according to claim 1,
In the method for producing a corrugated fin for a heat exchanger, the plurality of grooves (4a) are arranged to be inclined with respect to the longitudinal direction, and an inclined groove group (4) is formed between the non-grooved portions (5). .
The present invention described in claim 3 provides the method according to claim 2,
This is a method of manufacturing a corrugated fin for a heat exchanger in which the inclined directions of adjacent inclined groove groups (4) are opposite to each other.

The corrugated fin manufacturing method of the present invention is a process in which a plurality of grooves 4a are continuously formed in parallel on the plane of the strip-shaped metal plate 3 by a pair of forming rolls 1 and 2, and the transverse section thereof is formed into a shallow corrugated plane. And then, on the shallow corrugated plane, spaced apart at regular intervals in the longitudinal direction of the strip-shaped metal plate 3 and flatly crushing the corrugated plane to form the grooveless portion 5 there in the width direction, The belt-shaped metal plate 3 is folded back at the position of the groove-free portion 5 and is bent to form a bent portion 5a.
The bent portion 5a is a grooveless portion 5 that is fixed to the flat surface of the flat tube 6 by brazing, so that the heat transfer between the flat tube 6 and the corrugated fin 8 is improved. It can be secured. The non-grooved portion 5 can be made the minimum necessary, and in addition to the bent portion 5a, a large number of grooves 4a are arranged in parallel to form a shallow corrugated plane. The exchange performance can be improved to the maximum.
According to the invention of claim 2 and claim 3, since the inclined groove group 4 is formed between the non-grooved portions 5, a vortex is generated in the gas flowing therethrough to further improve heat exchange.

Explanatory drawing which shows the manufacturing method of the corrugated fin for heat exchangers of this invention. The principal part perspective view of the heat exchanger which has the corrugated fin 8 manufactured by the same method. Explanatory drawing which shows the manufacturing method of the other Example of this invention. Explanatory drawing which shows the state of the eddy current of the corrugated fin 8 of FIG. Explanatory drawing which shows the state of the vortex | eddy_current of the corrugated fin 8 of FIG.

Next, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is an explanatory perspective view of the manufacturing method of the first embodiment of the present invention, and FIG. 2 is a perspective view of a main part of a heat exchanger composed of corrugated fins and flat tubes by the same method.
In this corrugated fin manufacturing method, a band-shaped metal plate 3 wound in a roll shape is supplied between a pair of rolls 1 and 2, and a number of grooves 4 a are continuously formed in parallel on the plane. Therefore, the rolls 1 and 2 are formed with a large number of oblique ridges and recesses alternately, and the ridges of the other roll 2 mesh with the ridges of one roll 1. By such a roll, a shallow corrugation is formed on the plane of the belt-shaped metal plate 3.

  Next, in this example, a pair of press dies 7 is disposed downstream of the rolls 1 and 2, and the corrugated plane of the band-shaped metal plate 3 is crushed at every predetermined distance of the band-shaped metal plate 3, and there is no groove portion 5. Form. The width of the groove-free portion 5 is limited to the minimum necessary radius of curvature at which a bent portion can be formed in a later step. The non-grooved portions 5 are arranged perpendicular to the longitudinal direction of the belt-shaped metal plate 3 and are spaced apart from each other in the longitudinal direction at an amplitude pitch of the corrugated fins. Instead of the press die 7, the grooveless portion 5 can be formed by a pair of upper and lower rolls.

  Next, the belt-shaped metal plate 3 is folded back and folded at the position of the grooveless portion 5 to form a bent portion 5a. The bent portion 5a is formed in a state in which the grooveless portion 5 is formed by the pair of press dies 7, and the upstream side and the downstream side thereof are supported by a roll support (not shown), and the pair of press dies 7 are moved up and down as they are. The folded portion may be formed by moving in the direction. Or the formation part of the bending part 5a can also be provided in the downstream of the pair of press metal mold | die 7 separately. In this example, the groove 4 a is inclined in only one direction with respect to the longitudinal direction of the strip-shaped metal plate 3.

As shown in FIG. 2, the corrugated fins 8 formed in this way are located between the paralleled flat tubes 6, and the bent portions 5 a are in contact with the flat outer surface of the flat tubes 6. The contact portions are integrally brazed and fixed. The upper and lower ends of the flat tube 6 communicate with a tank (not shown), a heat medium for cooling flows through the flat tube 6, and an air flow 9 flows through the outer surface of the flat tube 6 and the corrugated fin 8 in the direction of the arrow. To do. Heat exchange is performed between the air flow 9 and the heat exchange medium in the flat tube 6.
In this example, the corrugated fins 8 are folded back by the bent portions 5a, so that opposing planar grooves 4a are formed in opposite directions. Then, the air flow 9 advances in the width direction of the corrugated fins 8 and a part thereof is guided to the inclined groove group 4 and rotates as shown in FIG. This promotes heat exchange.

Next, FIG. 3 is explanatory drawing which shows the manufacturing method of the corrugated fin of 2nd Example of this invention.
This example is different from that of FIG. 1 in that a large number of grooves 4a formed in the band-shaped metal plate 3 are continuous in a plane waveform. Then, a grooveless portion 5 is formed by a pair of press dies 7 at the top and valley portions of the groove 4a in plan view, and a bent portion 5a is formed at the position of the grooveless portion 5. In this case, the inclined groove groups 4 formed on the opposing planes are arranged in the same direction.
As a result, the air flow 9 circulates in the width direction of the corrugated fin 8 and a part thereof forms a vortex as shown in FIG. This vortex is formed in two upper and lower layers.
Note that the inclination angles of the inclined grooves formed on the opposing planes may be the same or different.

1, 2 rolls 3 strip metal plate 4 inclined groove group
4a Groove 5 Non-grooved part
5a Bent part 6 Flat tube 7 Press die 8 Corrugated fin 9 Air flow

Claims (3)

The bent portion (5a) of the corrugated fin (8) comes into contact with the flat outer surface of the parallel flat tubes (6), and the contact portion is brazed and fixed. The outer surface of the flat tube (6) and the corrugated fin (8) is a heat exchanger in which a gas flows, and in the method of manufacturing the corrugated fin for the heat exchanger,
A plurality of grooves (4a) are continuously formed in parallel on the plane of the belt-shaped metal plate (3) by a pair of forming rolls (1) and (2), and the transverse section is bent into a shallow corrugated plane;
Next, the shallow corrugated plane is spaced apart at regular intervals in the longitudinal direction of the strip-shaped metal plate (3), and the corrugated plane is flatly crushed to form a groove-free portion (5) in the width direction. And the step of folding back the band-shaped metal plate (3) at the position of the groove-free portion (5), and forming the bent portion (5a) there,
The manufacturing method of the corrugated fin for heat exchangers which comprises this. In claim 1,
A method for producing a corrugated fin for a heat exchanger, wherein the plurality of grooves (4a) are arranged to be inclined with respect to the longitudinal direction, and an inclined groove group (4) is formed between the non-grooved portions (5). In claim 2,
A method for manufacturing a corrugated fin for a heat exchanger, wherein the inclined directions of adjacent inclined groove groups (4) are opposite to each other.

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