JPH04203799A - Heat exchanger fin and its manufacturing method - Google Patents

Abstract

PURPOSE:To manufacture a fin having a large heat radiation area without useless material and to make a uniform heat radiation characteristics by a method wherein each of the fins is directed from a central part toward a radial outer side, its amplitude is gradually decreased and a pitch is gradually increased. CONSTITUTION:Fins 1 are formed into an arcular curved belt form and a vertical section along a longitudinal direction is bent into a wave form. The fins 1 can be manufactured by pressing a belt-like plate material from its extremity end toward its rear end in sequence for every unit element by using a die. The die has teeth portions 3 and the teeth are formed in such a way an amplitude of each of the teeth is continuously and gradually decreased from one axial side of a strip member to the other side and its pitch is continuously widened. That is, a height (h1) of a tooth at one end of a die 2 is higher than a height (h2) at the other end and a tooth width W1 is smaller than W2. the die 2 is a male die for a pressing operation, a metallic strip material is inserted between the male die and a femalie die mating with the male die bent and formed to make the fin 1.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a fin for a heat exchanger of a rotating part that is most suitable for keeping lubricating oil at an appropriate temperature, such as in an automobile diesel gear, and a method for manufacturing the same.

[Prior art]

It is preferable that the lower surface side protrusion of the differential gear (hereinafter referred to as differential gear) of the heat exchanger is as small as possible. Lubricating oil is filled in a groove approximately half way inside the casing of this differential gear device. Then, while the vehicle is running, the lubricating oil is supplied to the meshing portion of the gears in the differential. Needless to say, such oil requires an appropriate oil temperature for lubrication. However, it is extremely difficult to incorporate a heat exchange device that maintains the temperature of lubricating oil at an appropriate temperature inside the casing of the differential gear.

That is, it has been considered difficult to install an efficient heat exchanger with a relatively large heat radiation area in an extremely narrow space.

[Problem to be solved]

Therefore, the present applicant has already filed an application for a heat exchanger for a rotating part as Utility Application No. 1-141513.

However, the fins used in this heat exchanger need to be formed into an arcuate band shape to match the overall shape of the heat exchanger. It is impossible to directly mold such fins using conventional techniques, and it is necessary to cut a linearly formed strip into an appropriate shape. In this case, the material is wasted, and the formation of waves in each radial direction of the curved material becomes non-uniform, which may cause variations in the heat dissipation performance of each part.

[Means to solve the problem]

Therefore, an object of the present invention is to directly manufacture a fin with a relatively large heat dissipation area that can be attached to such a narrow space of a rotating part without wasting any waste, and to provide a fin with uniform heat dissipation in each part. The following structure is adopted to achieve the purpose.

That is, the fin of the present invention is directed to a fin whose overall planar shape is formed into an arcuate band shape, and whose longitudinal cross section along its longitudinal direction is formed into a wave shape. The ridges and troughs of each wave are formed in a radial direction from approximately the center of rotation of the curvature. Then, each part goes from the center side to the outside in the radial direction, and as the amplitude gradually decreases,
Along with this, the pitch is gradually widened. Each of the waveforms on different radii is formed so that the outer circumferential length of one pitch is approximately the same.

Next, the method of the present invention is a method of manufacturing a fin by successively press-forming unit elements from the tip to the rear so that the cross section along the longitudinal direction has a large number of continuous wave shapes. The following mold is used as a mold having teeth 3 for forming the element.

That is, the height of the tooth portion 3 gradually decreases from one side to the other, and the tooth width gradually increases accordingly. The fins are formed so that their outer circumferential lengths are approximately the same.Using such a mold, the overall planar shape of the fin is formed into an arcuate band shape, and the fins are formed in the longitudinal direction. The purpose is to manufacture a heat exchanger whose vertical cross section is formed into a wave shape.

[Function] According to the manufacturing method of the present invention, by sequentially press-forming a straight strip material from the tip to the rear for each unit element,
It becomes possible to directly mold a band-shaped wavy fin whose planar shape is curved into an arc.

〔Example〕

Next, embodiments of the present invention will be described based on the drawings.

FIG. 1 is an explanatory perspective view of a press mold used in the manufacturing method of the present invention, and FIGS. 2 to 5 show the fin material manufactured from the mold, and FIG. 2 shows the main parts thereof. 3 is a perspective view of the same, FIG. 4 is a sectional view taken along the TV-IV arrow in FIG. 3, FIG. 5 is a sectional view taken along the V-■ arrow in FIG. FIG. 7 is a perspective view of the second embodiment of the fin material of the present invention, FIGS. 8 to 12 show the usage state of the fin material, and FIG. 8 shows it in the heat exchanger 14. 9 is a perspective view of the same essential parts, FIG. 10 is a vertical cross-sectional view of the same main parts, and FIG. 11 is a vertical cross-sectional view of it attached to a differential gear device.
FIG. 12 is a front view of the same.

The heat exchanger to which the fin material of this example is applied is as shown in FIGS.
formed into a horseshoe shape. An arcuate recess (FIG. 9) is formed on the inner surface, and relatively small protrusions 16 protrude toward the inner surface at a distance from each other on the center line of the arcuate recess. This convex portion 16 forms a spacer between the pair of metal plates. A small flange portion 7 is formed on the outer periphery of each metal plate, and the edge of the small flange portion 7 is raised outward to form a rib 17 on the entire periphery. The ribs 17 increase the rigidity of the heat exchanger and also position both sides of the fin 1, which is the object of the present invention. Then, the pair of upper and lower metal plates are stacked on top of each other in opposite directions and are fluid-tightly joined at the small flange portion 7 on the periphery. A flat flow path 6 is formed inside, and cooling water inlets and outlets 15 are provided at both ends of the flat flow path 6. Furthermore, bolt holes 10 are provided at both ends of the heat exchanger and on the outer side of the cooling water inlet/outlet 15 in the longitudinal direction.

The fins 1 used in such a heat exchanger are of a corrugated fin type as shown in FIG. 3 or of a multi-entry type as shown in FIG. 7. In addition,
In the case of a corrugated fin type as shown in FIG. 3, appropriate louvers can be formed on the outer peripheral surface thereof.

Therefore, such a fin 1 has an overall planar shape formed in an arcuate band shape, and a longitudinal cross section along the longitudinal direction of the fin 1 which is bent into a wave shape.

The fin 1 can be manufactured by using a mold as shown in FIG. 1, for example, by sequentially press-forming a plate material having a band-like planar shape from the tip to the rear, unit by element. . This mold has teeth 3 in which the amplitude of the waves gradually decreases from one side to the other in the width direction of the strip material to be molded, and the pitch continuously widens accordingly. It is formed like this.

That is, the height hl of the teeth on one end side of the mold 2 is larger than the height h2 on the other end side, and the tooth width ratio 1 is smaller than -2. Moreover, these elements change continuously from one end to the other.

The outer circumference length of each cross section of this mold is 12 h.
+W=bl +2 hl +WI =b2+ 2 h2
+W2=constant. The fin manufactured by such a mold 2 has a shape that matches the mold 2 as shown in FIGS. 4 and 5. That is, this mold 2 serves as a male mold during press molding, and a metal strip is inserted between it and a matching female mold, and bent and formed as shown in FIGS. 3 to 5.

Then, the fin 1 as shown in FIG. 6 is formed as a whole.

Note that by forming a large number of unevenness on the side surface of the mold 2, a multi-entry type fin material as shown in FIG. 7 is formed. You can also do that. In this case as well, the amplitude on the center side of the curved fin is larger than on the outside, and the fin pitch is conversely smaller. That is, the fin pitch becomes thicker (and the amplitude becomes smaller) toward the outer side in the radial direction.Moreover, each waveform on a different radius is formed so that the outer circumferential length of one pitch is the same. Therefore, the fins 1 as shown in FIGS. 2 to 7 can be formed by sequentially forming linear strips from the tip to the rear using progressive press molding. 10th
As shown in the figure, it may be placed on the outer surface of the heat exchanger as an outer fin, and the two may be integrally fixed by brazing or soldering.

The heat exchanger 14 manufactured in this manner is installed inside the casing 8 of a differential gear of an automobile as shown in FIGS. 11 and 12. In this embodiment, the fins 1 are arranged only on one side of the heat exchanger, but they may be arranged on both sides. Furthermore, it is also possible to install this fin 1 inside the flat channel 6. And this heat exchanger 14
is arranged so as to fit over the outer periphery of the differential gear device 9. That is, it is arranged around the outer periphery of the differential gear device 9 housed in the casing 8 so as to partially surround it. The arrangement position is as shown in FIG. 12 so that the axle 11 and the axis of the heat exchanger are substantially coaxial. By arranging it in this manner, it is possible to avoid the drive pinion 12 portion of the differential gear device 9 and to effectively utilize the space within the casing 8. In this embodiment, the heat exchanger can be firmly fixed to the casing 8 by using bolt holes 10 provided at both longitudinal ends of the heat exchanger and inserting bolts therein. or,
Cooling water inlet/outlet 1 provided at both ends of this heat exchanger 140
5 is piped so that engine cooling water flows through it. This engine cooling water passes through a radiator to be cooled and then is guided into the flat flow path 6. As the ring gear 13 rotates, the lubricating oil in the casing 8 is efficiently spread over the fins 1 of the heat exchanger 14, and is efficiently cooled by the fins 1. In addition, lubricating oil is always stored in the lower part of the casing 8, and since about 1/3 of the heat exchanger 14 is disposed in this collecting part, the oil in the collecting part is also efficiently cooled.

〔Effect of the invention〕

The heat exchanger fin of the present invention has the above configuration. Further, in the case where the overall planar shape is formed into an arcuate band shape and the waveform is bent in the longitudinal cross section of the band, the formation of waves at each part in the radial direction can be made uniform. Thereby, it is possible to maintain uniform heat dissipation in each part in the radial direction, and to prevent the heat exchange medium that comes into contact with it from stagnation.

In addition, the multiwaves are formed in such a way that the amplitude gradually decreases from the center side toward the outside in the radial direction, and the pitch gradually increases accordingly, so that the circumferential length of one pitch of the multiwaves on different radii is Since they are each formed to be substantially the same, it is possible to form the main fin by bending a linear strip plate into a planar arc shape without waste.

Next, according to the fin manufacturing method of the present invention, by sequentially press-forming strip metal plates having straight planar shapes, a strip material having an arcuate planar shape can be formed without waste.

That is, it is possible to eliminate the waste of cutting out a band-shaped body whose overall planar shape is a straight line, as in the past, by cutting it into an arc-curved body.

[Brief explanation of the drawing]

FIG. 1 is an explanatory perspective view of a press mold used in the manufacturing method of the present invention, FIGS. 2 to 5 show the fin material manufactured from the mold, and No. A plan view, FIG. 3 is a perspective view of the same, FIG. 4 is a sectional view taken along the IV-IV arrow in FIG. 3, FIG. 5 is a cross-sectional view taken along the ■-■ arrow in FIG. Explanatory drawings, FIG. 7 is a perspective view of the second embodiment of the fin material of the present invention, FIGS. 8 to 12 respectively show the usage state of the fin material, and FIG. 8 shows the use of the fin material in the heat exchanger 14. A plan view of the application, FIG. 9 is a perspective view of the same essential parts, FIG. 1O is a longitudinal sectional view of the essential parts, and FIG.
FIG. 12 is a front view of the same. 1... Fin 2... Mold 3... Teeth
5...Element 6...Flat channel
7...Small flange part 8...Casing 9
... Differential gear device 10 ... Port hole 11.
... Axle 12 ... Drive pinion 13 ... Ring gear 14 ... Heat exchanger 15 ... Cooling water inlet/outlet 16 ... Convex part 17 ... Rib agent
Patent Attorney Kubo 1) Takumi

Claims (2)

[Claims] (1) In a fin whose overall planar shape is formed into an arcuate band shape and whose longitudinal cross section is bent into a waveform, the ridges and troughs of each wave are approximately at the center of rotation of the curvature. Each wave is formed in the radial direction from the center side toward the outside in the radial direction, with the amplitude gradually decreasing and the pitch gradually increasing accordingly, and each waveform on a different radius A fin for a heat exchanger, characterized in that each fin is formed so that the outer circumferential length of each pitch is approximately the same. (2) In a method of manufacturing a fin by sequentially press-forming unit elements from the tip to the rear so that the cross section along the longitudinal direction of the strip has a large number of continuous wave shapes, the tooth portion for forming the unit elements 3, the height of the tooth portion 3 is formed so that it gradually decreases from one side to the other in the ridgeline direction, and the tooth width gradually increases accordingly, and By using fins that are formed so that the outer circumferential lengths of the cross sections with different distances are approximately the same, the overall planar shape of the fin is formed into an arcuate band shape, and the longitudinal direction of the fin is A method for manufacturing heat exchanger fins whose longitudinal cross-sections are bent into a waveform.