JPS6124994A - Structure of tube and fin - Google Patents

Abstract

PURPOSE:To form a configuration favorable in strength with respect to a load vertical to the plane of the fin by attaching the fin to the tube through the plastic deformation of the tube. CONSTITUTION:The flat plate fin 2, provided with a hole having a diameter slightly larger than the outer diameter of the tube and projected to one side thereof by press forming, is manufactured, then, the tube is inserted into the hole and, thereafter, the tube 1 is expanded outwardly to connect the fin 2 to the tube 1. Strain is not caused compared with the case of welding, manufacturing cost may be reduced, the connecting strength thereof is increased compared with the case of force fit and this method is effective for the improvement of heat transfer efficiency. Connecting area between tube and fin may be obtained sufficiently and a structure, prominent in heat transfer characteristic and favorable in strength, may be obtained whereby it makes this method effective for the assembling of tube and fin.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention is a heat exchanger having a tube-fin structure,
In particular, this relates to the contact area where good thermal conductivity is required between the tube and the fins, and where non-weldable dissimilar materials are used, the tube is fixed by the friction of the contact surface by plastically deforming the part of the tube that contacts the fins. - Regarding fin structure.

An example of the prior art is shown in FIGS. 1 and 2.

FIG. 1 shows a structure in which a tube 1 and fins 2 are welded or brazed. In this structure, 1. Disadvantages include distortion caused by welding and difficulty in welding when the tube and fin are made of different materials.

FIG. 2 shows a structure in which fins 2 are press-fitted into tube 1. In this structure, the contact between the tube 1 and the fin 2 is only at the contact surface of the press-fitted part, and the reliability of heat transfer between the tube and the fin is low, and the strength is weak against loads in the direction perpendicular to the surface of the fin. There are drawbacks.

The purpose of the present invention is to increase the reliability of heat transfer between a tube and a fin by plastically deforming the contact surface on the tube side without welding, and to reduce the load in the direction perpendicular to the surface of the fin. The object of the present invention is to provide a tube-fin structure having an advantageous shape in terms of burning strength.

The present invention aims at the effect on the thermal properties and strength when assembling tubes and fins from different materials that cannot be welded in a tube-fin structure for increasing the heat transfer area and promoting heat exchange in a heat exchange device. It is something that In a tube-fin structure, heat transfer at the joint between the tube and fin is an important issue, unless the tube and fin are manufactured as one piece, and the larger the contact area, the better the heat transfer will naturally be. Further, by plastically deforming the tube and bringing it into close contact with the fins, it is advantageous in terms of strength.

Embodiments of the present invention will be described below with reference to the drawings.

Figure 3 shows one embodiment of the present invention, in which the tube side is made of stainless steel with excellent corrosion resistance and the fins are made of steel with excellent heat conduction properties. On the other hand, for example, a fin 2 having a hole slightly larger than the outside diameter of the tube that protrudes to one side is manufactured by press molding, and after this is inserted into the tube, the tube 1 is expanded outward and joined to the tube 1. be. FIG. 4 shows another embodiment, which differs from FIG. 3 in that the fins 2 are provided with radial slits and a reinforcing ring 3 is used.

According to this embodiment, there is no distortion compared to welding, the cost can be reduced, the joint strength is increased compared to press-fitting, and it is effective in improving heat transfer efficiency.

According to the present invention, a sufficient joint area between the tube and the fin can be obtained, resulting in a structure that has good heat transfer characteristics and is advantageous in terms of strength, which is effective in assembling the tube and fin.

[Brief explanation of drawings]

Figures 1 and 2 are cross-sectional views showing examples of prior art; Figure 3;
FIG. 4 is a sectional view showing an embodiment of the present invention. No. 10 Kaya Z mouth

Claims (2)

[Claims] 1. A structure comprising a tube having a circular cross-sectional shape and a fin attached in contact with the tube,
A tube-fin structure characterized by attaching fins by plastically deforming the tube. 2. 2. The tube-fin structure according to claim 1, wherein, in the tube and fin, by plastically deforming the tube, it is possible to fix the fin and at the same time fix movement in a direction perpendicular to the surface of the fin.