JPH0149565B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an apparatus for forming high-density acicular corrugate fins suitable for reducing the size and weight of heat exchangers.

When exchanging heat between two fluids inside and outside a tube, a heat exchanger with fins is used, which improves heat transfer performance by adding fins to the fluid side with a low heat transfer coefficient.
For example, a heat exchanger tube 02 equipped with corrugated fins or louvered corrugated fins 01 shown in FIG. 1 has been used as a heat exchanger for a car air conditioner.

As shown in FIG. 2, this corrugated fin 01 with louvers is made by feeding a band-shaped metal plate 03 between a pair of gear rolls 04 facing each other, and forming a cutting part and a forming part on the tooth surface of the gear roll 04 to form a louver. In addition to cutting and forming, rough waveform forming is performed.
Thereafter, the top of the fin is pressed by a presser spring plate 06 equipped with a pressure adjustment jig 05 to restrict the feeding, and the fin is compression-molded into a predetermined pit, which is then cut into a predetermined length with a cutter 07.

However, in order to meet the recent demand for lower fuel consumption for vehicles, reducing the weight of the vehicle is also an important factor, and it is also necessary to reduce the weight and reduce the weight of heat exchangers for car air conditioners, engine cooling, etc. that are installed in vehicles. Miniaturization is required. To meet this requirement, it is essential to improve the heat transfer performance of the heat exchanger, and instead of corrugated fins or corrugated fins with louvers, needle-shaped fins 08 are formed with high density as shown in Figure 3. It has been proposed to use needle-like corrugated fins 09.

However, this needle-like corrugated fin 09 has lower rigidity in the fin height h direction than the louvered corrugated fin 01, and in order to achieve high performance, it is necessary to corrugate at a high density, so the fin pitch P is narrowed and the rigidity is further increased. It is difficult to use the conventional molding equipment for corrugated fins with louvers shown in Fig. 2 as it is because precision finishing is required, and there is a desire to develop equipment that can perform molding efficiently.

The present invention has been made in view of such a need, and an object of the present invention is to provide a molding apparatus for needle-like corrugated fins that can be molded accurately and at high speed. The structure of the present invention that achieves the above object is provided with a pair of opposing gear rolls that rough-shape a band-shaped metal plate formed in advance from a group of ladder-like or net-like needle fins into a corrugated shape, and to A pair of screw shafts are rotatably provided on both sides parallel to the feeding direction of the plate and sandwiching the feeding direction. The blade is compression-molded into a wave shape and is spirally provided with a predetermined pitch toward the tip.

Hereinafter, one embodiment of the present invention will be described in detail based on the drawings.

The needle-like corrugated fin forming apparatus of the present invention includes:
This is an apparatus for corrugating the band-shaped metal plate 1 shown in FIG. 4a, which is punched out in a ladder shape using upper and lower molds 2, and needle-like fin groups are formed thereon, as shown in FIG. 4b, which shows its planar state. As shown in FIG. 2, a rough forming section 4 for roughly forming the primary processed band metal plate 3 punched into a ladder shape and formed with needle-like fin groups into a wave shape, and a rough formed secondary processed band metal plate 5 that have been roughly formed are placed in a predetermined manner. A compression molding section 6 performs compression molding to a high-density fin pitch P of
It is made up of.

In the rough forming section 4, a pair of gear rolls 7 that mesh with each other and are driven to rotate at a constant speed are provided on the left and right in a horizontal plane, and the primary processed metal strip punched in the shape of a ladder is fed between the pair of gear rolls 7. The plate 3 is formed into a corrugated shape. For this pair of gear rolls 7, one whose axial length is slightly longer than the width of the stacked metal plate 1, that is, the height h of the fins when attached to the heat transfer tube, or a ladder-shaped gear roll is used. Since it is sufficient to roughly form only both ends of the shaft into a corrugated shape, thin gear rolls may be attached to both ends of the shaft to which the gear roll 7 is attached, and there may be no gear portion in the middle. Furthermore, the tooth profile is formed so that the tooth tip and tooth bottom portions are arcuate, which is necessary for corrugates, and do not form acute angles.

Next, the compression molding section 6 compresses the rough formed secondary processed band-shaped metal plate 5 into fin pitches to a predetermined high density, as shown in FIGS. 5 to 7.
Bearing support plates 9 are provided at both ends in the feeding direction of the secondary processed strip metal plate 5, and screw shafts 10 are rotatably attached via bearings to both ends parallel to and sandwiching the feeding direction. The bearing is movable along the bearing support plate 9 and the screw shaft 1
You can adjust the 0 interval. On the outer periphery of this screw shaft 10, the outer periphery tip comes into contact with the trough portion of the secondary processed band-shaped metal plate 5 which has been roughly formed into a corrugated shape, and is fed forward in the feeding direction as the screw shaft 10 rotates. Thus, the blades 11 to be compression-molded to a predetermined fin pitch are spirally attached so that the spacing gradually narrows toward the tip in the feeding direction so that a predetermined fin pitch is achieved near the tip. Since the screw shafts 10 to which the blades 11 are spirally attached are driven to rotate in opposite directions, the respective spiral directions are reversed and the screw shafts 10 are moved forward in the feeding direction by rotation. For this rotational drive, a driven gear 12 that meshes with a pinion of an electric motor (not shown) is attached to a telescoping shaft 13 that is mounted perpendicularly to the screw shaft 10 and is retractable.
One screw shaft 10 is rotationally driven through the bevel gear 14 at the other end and the bevel gear 15 at one end of the screw shaft 10 .
The transmission gear 16 at the other end of 0 is the intermediate gear 17, 18
By rotating the gear 19 attached to the other end of the other screw shaft 10 through the screw shaft 10, the screws rotate in opposite directions and at the same speed. In addition, the telescopic shaft 13
By providing the intermediate gears 17 and 18, when the screw shaft 10 is slid and the interval between them is adjusted, the meshing state of the bevel gears 14 and 15 is ensured, and the transmission gear 16 and the gear 19 are connected to the intermediate gear 1.
The distance between the axes can be moved in parallel while being circumscribed along the lines 7 and 18.

Although not shown, a gear roll 7 for rough forming is also provided.
The rotation speed of the screw shaft 10 and the screw shaft 10 are connected to each other so that the rotation speed is constant. For example, if the number of teeth of the gear roll 7 is n, the rotation speed of the gear roll 7 is 1/n of the rotation speed of the driven gear 12. Set.

Also, a bottom pedestal 20 that supports the bottom of the fins fed between the screw shafts 10 is mounted on the bed 8.
A cylindrical feed guide 21 with a large diameter inlet for guiding the feed is provided on the feed side of the bottom pedestal 20, and a discharge guide 22 for guiding the discharge is provided on the discharge side. is provided. In addition, 24
is a counter that measures the number of revolutions of the screw shaft 10.

In the forming process using the apparatus of the present invention configured as described above, first, as a pre-processing step, a band-shaped metal plate 1 is punched out in a ladder shape using upper and lower molds 2 to produce a primary processed band-shaped metal plate 3 in which needle-like fin groups are formed. . Thereafter, the gear roll 7 and the screw shaft 10 of the apparatus of the present invention are each driven to rotate, and the primary processed band-shaped metal plate 3 is sent between the gear rolls 7 to obtain a secondary processed band-shaped metal plate 5 roughly formed into a corrugated shape. Then, this secondary processed band-shaped metal plate 5 is passed through the feed guide 21 to the screw shaft 10.
When the blades 11 are sent in between, the tips of the spirally attached blades 11 come into contact with the troughs of the waveform and are sent forward as the screw shaft 10 rotates.At this time, since the blades 11 are spiral, the fin pitch gradually increases It is narrowed and compression molded to a predetermined fin pitch P. Then, the needle-like corrugated fin 23, which has finally separated from the blade 11 and has become a product, is sent out from the discharge guide 22. In this way, by continuously driving the gear roll 7 and the screw shaft 10 at a constant rotation ratio, the needle-like corrugated fins 23 can be continuously molded, and the number of molded fins can be known by the counter 24. In addition, with this device, needle-like corrugated fins can be compression molded with a pitch of 0.8 to 1.0 mm, whereas conventional corrugated fins have a pitch of 1.5 to 2.0 mm. Even a group of needle-like fins with low rigidity can be compressed and molded with high accuracy to a predetermined fin pitch according to the pitch of the blades without the need for additional molding, and can be easily molded at high speed.

Incidentally, in the above embodiment, the forming of a band-shaped metal plate in which a group of ladder-like needle-like fins was formed was explained.
The present invention is not limited to this, and for example, a material having a network of needle-like fins as shown in FIG. 8 can be easily compression-molded by the apparatus of the present invention.

As described above in detail with the embodiments, according to the present invention, the rough forming part by gear rolls,
The spiral blades installed on the screw shaft allow for continuous and high-speed machining, as well as high machining accuracy.

[Brief explanation of drawings]

FIG. 1 and FIG. 2 are a perspective view of a conventional corrugated fin with a louver and a schematic configuration diagram of a forming device,
FIG. 3 is a perspective view of a needle-like corrugated fin, which is an example of the object to be molded according to the present invention, and FIGS. Front view, b is plan view, 5th
7 to 7 show the compression molding section, FIG. 5 is a plan view, FIG. 6 is a front view, FIG. 7 is a right side view, and FIG. 8 is a front view of another example of the molding object of the present invention. It is a diagram. In the drawings, 1 is a band-shaped metal plate, 2 is a mold, 3 is a primary processed band-shaped metal plate, 4 is a rough forming part, 5 is a secondary processed band-shaped metal plate, 6 is a compression forming part, 7 is a gear roll, 8
is a bed, 9 is a bearing support plate, 10 is a screw shaft, 11 is a blade, 12, 14, 15, 16, 1
7, 18, 19 are gears, 13 is a telescopic shaft, 20 is a bottom pedestal, 21 is a feeding guide, 22 is a discharge guide,
23 is a needle-like corrugated fin.

Claims (1)

[Claims] 1 A pair of opposing gear rolls are provided for roughly forming a band-shaped metal plate on which ladder-like or net-like needle fin groups are formed into a corrugated shape, and a pair of gear rolls facing each other are provided, and the rollers are parallel to the feeding direction of the roughly-formed band-shaped metal plate. A pair of screw shafts are rotatably provided on both sides of the screw shaft, and a blade is attached to the tip of the screw shaft, which is compressed into a predetermined wave shape by contacting the valleys of a rough-formed corrugated metal plate on the outer periphery of the screw shaft. 1. An apparatus for forming needle-like corrugated fins, characterized in that the fins are formed in a spiral shape so as to have a predetermined fin pitch in the opposite direction.