JPH01218726A - Member for heat exchanger - Google Patents

Abstract

PURPOSE:To improve the quality of a heat exchanger by performing cutting in parallel to the flowing direction of a crystal grain on the aluminum stock whose flowing direction of the crystal grain is in one direction and whose crystal grain flow is uniform and forming a tongue like fin. CONSTITUTION:A tubular body 1 made of aluminum is made by an indirect extruding machine. Numerous tongue like fins 3 are formed on both faces of the tubular body 1 by cutting the both faces of this tubular body 1 in the extruding direction C, i.e., in the flowing direction of the crystal grain by a cutter. The quality of a heat exchanger can thus be improved.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application This invention relates to heat exchange tubes for vehicle condensers and the like in which tongue-like fins are formed, heat sinks for mounting semiconductor elements, heat sinks for PTC heaters, and heat exchanger members. Regarding.

Conventional technology Conventional heat exchanger components such as heat exchange tubes and heat sinks on which tongue-shaped fins are formed are made by cutting an aluminum material obtained by direct extrusion to form tongue-shaped fins. be.

Problems to be Solved by the Invention However, aluminum materials obtained by direct extrusion have variations in metal flow, residual stress, and heat treatment, and when these are cut to form tongue-shaped fins, as shown in Figure 8. , the fin falls down ((a) in the same figure)
, opening ((b) in the same figure), waving ((c) in the same figure), meandering ((d) in the same figure), variation in fin pitch ((e) in the same figure)
) etc. will occur. For this reason, there are problems in that defective products are likely to occur, resulting in poor yields, and even if the product is not defective, it is often necessary to repair the side portion of the fin tip by cutting.

In addition, recently there has been a demand for a high-precision heat radiator for PTC heaters with a small fin pitch of the tongue-shaped fins, but if this heat radiator is manufactured from a material obtained by direct extrusion as in the past, the tips of the fins There is a problem that comrades come into contact and heat exchange efficiency is not good.

Therefore, the inventor of the present invention conducted extensive research and discovered that if the flow of crystal grains is uniform, the fins will be extremely less likely to fall.

This invention was made based on the above discovery, and an object thereof is to provide a heat exchanger member that can improve yield and quality.

Means for Solving the Problems The heat exchanger member according to the present invention is produced by cutting an aluminum material in which the flow direction of the crystal grains is unidirectional and uniform, parallel to the flow direction of the crystal grains. It is characterized by the formation of tongue-like fins. An aluminum material in which the crystal grains flow in one direction and the crystal grains flow uniformly can be obtained by indirect extrusion.

Effect of the Invention As a result of various experiments conducted in order to obtain a good tongue-shaped fin, the present inventor has determined the flow direction of the crystal grains of the material, the uniformity of the crystal grains, and the relationship between the flow direction of the crystal grains and the cutting direction. was found to have a significant influence. In order to obtain a good tongue-shaped fin, it is sufficient to use a material in which the flow direction of crystal grains is unidirectional and uniform, and to perform cutting parallel to the direction of crystal flow. I found out.

That is, as shown in FIG. 9, when cutting a material (arrow B) and the direction of the crystal flow (arrow A) are no longer parallel, so the cutting resistance is no longer uniform, and the formed tongue-like fin Y increases in the direction of decreasing cutting resistance. becomes smaller in the larger direction. As a result, the fins Y fall down, open, wave, meander, and vary in fin pitch.

On the other hand, as shown in Fig. 10, when cutting a material , the cutting resistance becomes uniform, so the fin Y falls down and opens,
Waving, meandering, variations in fin pitch, etc. will no longer occur. Such a material in which the crystal grains flow in one direction and the crystal grains flow uniformly can be obtained by indirect extrusion.

EXAMPLE Hereinafter, an example in which the present invention is applied to a heat sink for a PTC heater will be described with reference to FIGS. 1 to 5.

1 and 2 show a heat sink for a PTC heater. This heat sink is made of aluminum, and has a large number of tongue-shaped fins (3) formed on both sides of a tube (1) having a cavity (2) for attaching a PTC thermistor.

As shown in Fig. 3, this heat radiator is first made into an aluminum tube body (1) using an indirect extruder (11).
Thereafter, as shown in FIG. 4, both sides of the tube (1) are cut with a cutter (12) in the extrusion direction (direction indicated by C), that is, in the direction of crystal grain flow. It is manufactured by forming a large number of tongue-like fins (3) on both sides of 1).

As in the heat sink shown in FIG. 5, tongue-like fins (3) having a notch (4) at the center of the width of the finished end may be formed on both sides of the tube (1). Such a notch (4)
In order to form the tongue-shaped fins (3), a tube body (1) having grooves extending in the length direction at the center of the width of both sides is made, and both sides of this tube body (1) are cut to form the tongue-shaped fins (3).

The tube body (1) made by indirect extrusion method is extruded in direction A.
In the heat dissipating body shown in FIG. 1 in which the tongue-shaped fins (3) were formed by cutting, no bending of the fins occurred. On the other hand, if the tube body (la) made by direct extrusion is cut in the extrusion direction to form the tongue-like fins (3a), the fins will bend as shown in Figure 6. (Fin tilt) occurred. Further, the fin rows meandered and the tips of the fins opened.

The tube body (1) made by indirect extrusion method is extruded in direction A.
In the heat dissipating body shown in Fig. 5, in which tongue-shaped fins (3) with notches (4) are formed by cutting, the fins do not open, and even if the fin pitch is reduced, the tips of the fins are in contact with each other. There was nothing to do. On the other hand, when the tube (l a) made by the direct extrusion method is cut in the extrusion direction to form a tongue-shaped fin (3a) with a notch (4a), as shown in FIG. As such, the fins opened.

When the fin pitch was reduced, the tips of the fins came into contact with each other.

Even when tongue-shaped fins were formed by cutting a tube made by indirect extrusion in the direction opposite to the extrusion direction A, bending of the fins and opening of the fins did not occur.

Effects of the Invention The heat exchanger member according to the present invention is produced by cutting an aluminum material in which the flow direction of the crystal grains is uniform on one side and in parallel to the flow direction of the crystal grains into a tongue-like shape. Since the fins are formed, the tongue-shaped fins do not fall down, open, wave, meander, or vary in fin pitch, and the quality of the heat exchanger can be improved. Furthermore, the present invention can be applied to heat exchangers that require high precision, such as PTC heaters, where tongue-like fins could not be formed in the past.

[Brief explanation of the drawing]

1 to 5 show embodiments of the present invention, FIG. 1 is a cross-sectional view of a heat dissipating body for a PTC heater in which tongue-shaped fins are formed, and FIG. 2 is a vertical cross-sectional view of FIG. 1. , Figures 3 and 4
The figure shows the manufacturing process of the heat sink, FIG. 5 is a cross-sectional view showing a heat sink in which tongue-shaped fins with notches are formed, FIG. 6 is a cross-sectional view showing a comparative example, and FIG. A cross-sectional view showing another comparative example, FIG. 8 is a diagram showing a conventional example, FIGS. 9 and 10.
The figure is a diagram for explaining the invention in detail, and FIG. 9 is a diagram showing an entrance platform in which a tongue-like fin is formed by cutting a material in which the crystal flow direction is not unidirectional and the crystal flow is not uniform; FIG. 10 is a diagram showing a case where a tongue-like fin is formed by cutting a material in which the crystal flow direction is unidirectional and the crystal flow is uniform. (1)... tube body, (3)... tongue-like fin. Patent applicant: Showa Aluminum Co., Ltd.
Director Einosuke Kishimoto (4 others) Ward Law%'J Field (a) Figure 10 (a) (b) (b) Figure 9

Claims (1)

[Claims] A member for a heat exchanger in which tongue-shaped fins are formed by cutting an aluminum material in which the flow direction of crystal grains is unidirectional and uniform, parallel to the flow direction of the crystal grains.