JPS6361892A - Heat exchanger for automobile - Google Patents

Abstract

PURPOSE:To make the length of louvers longer and make the junction area between a curvature part and an outer wall of a tube wider by a method wherein at a plurality of straight line parts of wave-shaped fins, louvers are cut and raised so as to be in parallel mutually along their total length and the curvature at a curvature part is made longer than a half of two adjoining interval distances at plural straight line parts. CONSTITUTION:Fins 1 are composed of straight line parts 11 which are arranged to be at right angles to the longitudinal direction of the tubes 2 between two adjoining tubes 2 and curvature parts 12 connecting continuously both ends of plural straight line parts 11. Each part 11 is in parallel to other and at each part 11 a louver 1a is cut and raised along its total length. The curvature part 11 is formed in a circular arc form with a fixed curvature and its curvature radius is larger than a half of two adjoining interval distances. Combinated assembling body is carried into a furnace and solder material is melted and solidified to make junction parts 3. As the radius of the curvature R at the part 12 is longer than a half of the interval distance Pf between the parts 11 at this time, the facing area between the part 12 and the outer surface of the tube 2 is secured to be sufficiently wider.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a heat exchanger for an automobile, and can be used, for example, as an automobile radiator.

[Conventional technology]

FIG. 2 is a partial perspective view of a conventional heat exchanger, and FIG. 3 is a longitudinal sectional view thereof.

The corrugated fins 1 and the flat tube 2 are joined with a brazing material to form a joint 3. A plurality of louvers 13 are cut out in the straight portion 11 of the fin 1 for the purpose of improving performance.

In order to further improve the heat exchange performance in such a heat exchanger, as shown in FIG.
are arranged so as to be inclined with respect to the tube 2. That is, in the one shown in FIG. 3, the fins 1 are arranged in parallel so as to connect the adjacent tubes 2 at the shortest distance, but the straight portions 11 are arranged so as to be inclined with respect to the tubes 2, It is conceivable to increase the length of the louver 1a formed in the straight portion 11 compared to that shown in FIG.

[Problems to be Solved by the Invention] However, in the case where the straight portion 11 is arranged so as to be inclined with respect to the tube 2 as shown in FIG. 4, the following problem occurs. Figures 5 and 6 are A in Figure 4.
-A sectional view and l3-B sectional view. As shown in FIGS. 5 and 6, the intervals between the louvers 1a are close in the section 1-A, whereas in the section B-B shown in FIG. 6, the intervals between the louvers 1a are sparse. . Therefore, the flow of the heat exchange fluid passing through the fins is as follows in the section A-A:
Normally, the flow becomes a V-shaped flow, but there is a problem in that the flow does not become a V-shaped flow at the cross section B-B, and the effect on the roux cannot be achieved satisfactorily.

Furthermore, in the case shown in FIG. 4, the area of the joint between the tube 2 and the curved part 12 that continuously connects each of the straight parts 11 is small, and the joint between the fin 1 and the tube 2 cannot be secured sufficiently. There is a problem.

[Means for solving problems]

In the present invention, the following measures have been taken to solve the above-mentioned problems.

That is, in a heat exchanger that includes a plurality of tubes through which a fluid to be heat exchanged flows and wavy fins arranged between the tubes, the fins are connected from one tube to the other of two adjacent tubes. It consists of a plurality of straight parts facing the tube, and a curved part that continuously connects two adjacent straight parts and is fixed to the outer wall of the tube. The plurality of straight portions are arranged parallel to each other, and a louver is cut in each of the straight portions over the entire length thereof. Furthermore, the radius of curvature of the curved portion is set to be 1/2 or more of the distance between two adjacent linear portions of the plurality of straight portions.

〔Effect of the invention〕

In the present invention, the radius of curvature of the curved portion is set to be 1/2 or more of the distance between two adjacent linear portions of the plurality of straight portions, so that the straight portion can be formed as long as possible. As a result, the length of the louver formed over the entire length of the straight portion can be made longer. therefore,
By increasing the length of the loop, the heat exchange performance can be sufficiently improved compared to conventional ones.

Further, the joint area between the curved portion 1a and the outer wall of the tube 2 can be made large as in the conventional case, and sufficient joint strength can be ensured.

〔Example〕

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

A wavy bent fin 1 is arranged between two adjacent tubes 2 of a plurality of tubes 2 arranged in parallel.

This fin 1 has a straight portion 1 arranged between two adjacent tubes 2 so as to be perpendicular to the longitudinal direction of the tubes 2.
1, and a curvature portion 12 that continuously connects both ends of the plurality of straight portions 11.

This curved portion 12 is joined to the outer wall of the tube 2 by means such as brazing, and this brazing is performed at the portion of the tube 2.
A joint 3 is formed between the fin 1 and the fin 1.

The straight portions 11 are located parallel to each other, and a louver 1a is cut out over the entire length of each straight portion 11.

The curvature portion 12 has a circular arc shape with a constant curvature.
The radius of curvature R has a value larger than 1/2 of the distance Pf between two mutually adjacent straight portions 11 described above. The connecting portion between the straight portion 11 and the curved portion 12 forms a corner portion 13.

The above-mentioned louver 1a is cut out as long as possible in the straight portion 11, and the end portion of the louver 1a is formed adjacent to the corner portion 13. Further, since the straight portions 11 are arranged parallel to each other, the spacing density of the louvers 1a is set to be equal in any cross section of the straight portions 11.

Such fins 1 and tubes 2 are joined by the following method. That is, the fins 1 and the tubes 2 whose outer surfaces are plated with brazing material in advance are alternately combined. This combined assembly is passed through a furnace, and the brazing material is melted and solidified to form the joint 3. At this time, the radius of curvature R of the curved part 12 is equal to or more than 1/2 of the distance PI of the straight part 11, so that the opposing area between the curved part 12 and the outer surface of the tube 2 can be sufficiently long (secured). , the joint portion 3 can be formed with sufficient length. That is, the joint between the tube 2 and the fin 1 can be ensured with sufficient strength.

In this way, the fin 1 and the tube 2 are joined.

The fin 1 can be formed by roller forming, for example, by the method disclosed in Japanese Patent Laid-Open No. 11i55-110892. However, in the above-mentioned publication, the present embodiment shows a fin in which the portion corresponding to the curvature portion 12 is a flat portion.
In order to make the portion corresponding to No. 2 a flat portion, it is necessary to set the cutting edge of the forming roller in a special shape in advance.

However, since the curvature portion 12 of this embodiment has an arcuate shape with the above-mentioned curvature, it can be formed relatively easily when being formed using a forming roller.

As described above, in this embodiment, the radius of curvature R of the curvature section 12 is set to be 1/2 or more of the distance P of the straight section 11, so the curvature section 12 becomes a circular arc section with a sufficiently large curvature. As a result, the length of the straight part 11 can be made as long as possible.As a result, the length of the louver 1a formed in the straight part 11 can also be made long, and sufficient heat exchange performance can be exhibited. Furthermore, since the straight portions 11 are arranged parallel to each other and the louvers 1a are formed in the parallel straight portions, the intervals between the louvers 1a are the same no matter which cross section of the straight portion 11 is taken. As shown in FIG. 5, the air flowing between the fins 1 can fully utilize each louver 7.
You can get the flow. That is, each louver 1a can exhibit uniformly high heat transfer performance.

The louver la of this embodiment is a louver with a straight portion 11 cut out as shown in FIG. 2, but for example, as shown in FIG. It is also possible to do this.

Further, as shown in FIG. 8, the slits 1a may be inclined at a certain angle so as to be parallel to each other.

Furthermore, as shown in FIG. 9, the slit 1a may be formed at an inclined angle so as to be symmetrical with respect to its center.

[Brief explanation of drawings]

Fig. 1 is a sectional view showing an embodiment of the present invention, Fig. 2 is a partial perspective view of a conventional example showing tubes and fins, Fig. 3 is a sectional view showing the conventional example, and Fig. 4 is a conventional example. 5 is a sectional view taken along line A-A in FIG. 4, and FIG. 6 is taken along line B in FIG. 4.
-B sectional view, FIG. FIGS. 8 and 9 are schematic cross-sectional views showing other examples of application of the present invention. DESCRIPTION OF SYMBOLS 1... Fin, la... Louver, 2... Tube, 11... Straight part, 12... Curved part, 13... Corner part.

Claims (1)

[Scope of Claims] Comprising a plurality of tubes through which a fluid to be heat exchanged flows, and fins arranged between the tubes, the fins meander between two adjacent tubes. A wavy fin that progresses in the longitudinal direction, and has a plurality of straight sections extending from one tube to the other of two adjacent tubes, and continuously connects two mutually adjacent straight sections. , a curved part fixed to the outer wall of the tube, arranged parallel to each other in the plurality of straight parts, each straight part has a louver cut along its entire length, and the curved part A heat exchanger for an automobile, wherein the radius of curvature is 1/2 or more of the distance between two adjacent ones of the plurality of straight portions.