JPS5928420B2 - Manufacturing method of multistage V-pulley - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention utilizes a stepped cup-shaped pulley material to create V-shaped parts with different diameters.
The present invention relates to a method for manufacturing a multistage pulley having grooves in multiple stages.

Conventional methods for manufacturing multistage pulleys include, for example, Japanese Patent Publication No. 53-
As shown in Japanese Patent No. 10553, reverse drawing (also called step drawing or shoulder drawing) is applied to the bottom and large diameter step of a cup-shaped material with two steps, and a small diameter step is formed in the middle. A secondary material was formed having two large and small annular walls with different diameters on the top and bottom, each of which had an annular wall portion with a double wall structure in the upper half, and this secondary material was subjected to the V-groove forming process. .

Furthermore, due to the shape and structure of the secondary material, the V-groove forming process had to be applied first to the large diameter part and then to the small diameter part. Therefore, in the conventional method for manufacturing a two-stage V pulley, there was a problem in that the two-stage cup-shaped material had to be further subjected to reverse drawing to form a secondary material, which required time and effort.

Additionally, when V-groove forming is performed, the material generally stretches toward the opening direction of the material, but since V-groove processing is performed on the large diameter section first and the small diameter section later, , there was a problem that there was no elongation clearance that occurs during the V-groove forming process of the small diameter portion, and this immediately results in dimensional errors between the V-grooves. The present invention has been made to solve these problems, and is a method in which groove forming is performed directly on the stepped pulley material, eliminating the need for the labor of forming a secondary pulley material. The groove forming process is performed from the small diameter side of the bottom side of the pulley material, and the elongation caused by the forming process can be released to the open end side, making it possible to maintain high dimensional accuracy between the V grooves. A method for manufacturing a V-pulley is provided.

Hereinafter, one embodiment of the present invention will be described with reference to the drawings.

FIGS. 1 to 5 show an embodiment of the present invention in the order of steps.

First, a stepped cup-shaped pulley material 1 made of sheet metal as shown in FIG. 1 is formed.

This is formed from a sheet metal material by drawing. The pulley material 1 has a two-stage stepped cup shape with large, medium, and small diameter portions 2, 3, and 4 on the peripheral wall. Next, the small diameter portion 4 of this pulley material 1 is subjected to a V-groove forming process as shown in FIGS. 2 and 3. That is, first, a lower rotary molding mold (hereinafter referred to as the lower mold) 5 receives the stepped portion of the small diameter portion 4 and the medium diameter portion 3 of the pulley material 1, and an upper rotary molding mold (hereinafter referred to as the upper mold) 6 receives the stepped portion of the small diameter portion 4 and the medium diameter portion 3 of the pulley material 1. The upper end wall portion 7 of the pulley material 1 is pressed to rotate the small diameter portion 4 while applying a compressive force in the axial direction. Then, the outer circumferential wall surface of the small diameter portion 4 is pressed in the radial direction with the preliminary V groove forming roller 8 to form a preliminary V groove.
Form the groove 9. Next, a final V-groove forming roller 10 is pressed onto the preliminary V-groove 9 instead of the preliminary V-groove forming roller 9 to form a V-groove 11 of a desired shape. The upper end wall 7 is also formed into a concave shape by pressing the lower mold 5 and the upper mold 6 together. Next, the large diameter portion 2 of the pulley material 1 is subjected to a V-groove forming process as shown in FIGS. 4 and 5. That is, first, the lower die 12 is used to lock the opening edge 13 of the pulley material 1 into the stepped portion 1.
2' is locked and received from the outer circumferential side, and the upper mold 14 presses the step between the medium diameter part 3 and the large diameter part 2 of the pulley material 1, and the large diameter part 2
is rotated while applying compressive force in the axial direction. and,
A preliminary V-groove forming roller 15 presses the outer peripheral wall surface of the large diameter portion 2 in the radial direction to form a preliminary V-groove 16. Next, the pulley material 1 is transferred to upper and lower molds 17 and 18 for final forming, and a final V-groove forming roller 19 is pressed into the preliminary groove 16 instead of the preliminary V-groove forming roller 15 to form the desired shape. V-groove 20 is formed. After forming the V-groove, the opening edge 13 of the pulley material 1 is pressed in the radial direction with an edge finishing roller 21 to form a desired edge shape. According to the above method, since V-groove forming is directly performed on the stepped pulley material 1, the time and effort of forming a secondary pulley material is unnecessary, and the forming process can be shortened. .

In addition, the V-groove forming process is performed on the small diameter portion 4 on the bottom side of the pulley material 1.
Since it is performed from the side, the elongation caused by the forming process can be released to the open end side. Therefore, unlike the conventional case where there is no escape for elongation, the dimension A between the V grooves 11 and 20 can be reduced. High accuracy can be maintained. Moreover, according to such a manufacturing method, the equipment to which the manufacturing method is applied is equipped with at least the manufacturing equipment used in normal rolling processing, such as a lower rotary mold and a V-groove forming roller. Since it can be carried out once it has been established, it has the advantage that the cost of manufacturing equipment can be extremely reduced.

In the above embodiment, the middle diameter part 3 of the pulley material 1 is simply cylindrical, but as shown in FIGS. 6 and 7, for example, the middle diameter part y extends from the bottom side to the opening side. Of course, the method of the present invention can also be used in cases where the diameter is tapered to gradually increase.

Further, in each of the above embodiments, the bottom portions 7, 7' of the pulleys are formed into a concave shape, but for example, as shown in FIGS.
Of course, the method of the present invention can also be used in the case where the bottom r't)s is formed into a convex shape as shown in the figure.

As is clear from the above description, the method for manufacturing a multistage pulley of the present invention involves forming a stepped cup-shaped pulley material having at least large, medium, and small diameter portions on the peripheral wall, and forming this pulley material into upper and lower portions. A groove forming roller is loaded between rotary molds and rotates while applying compressive force in the axial direction to the peripheral wall, and presses the outer surface of the peripheral wall from the radial direction. Since the grooves are formed in the small diameter part and the large diameter part by pressing sequentially from the small diameter part side, when forming the V groove in the large diameter part, the elongation of the material escapes to the opening side of the pulley material, and the Since the elongation of the formed small diameter portion toward the groove side is effectively avoided, the dimensional accuracy between the grooves is significantly improved, and there is no need for the labor of forming the secondary pulley material as in the manufacturing method of Japanese Patent Publication No. 53-10553. It is no longer necessary, and furthermore, it can be applied with a simple rolling device without the need for complicated manufacturing equipment.
It has excellent effects.

[Brief explanation of drawings]

Figures 1 to 5 show one embodiment of the present invention.
The figure is a cross-sectional view showing a pulley material, FIGS. 2 to 5 are cross-sectional views sequentially showing the forming process, and FIGS. 6 and 7 are half-sections of a pulley material and a finished product showing other embodiments of the present invention. Sectional view, No. 8
9 and 9 are cross-sectional views of a pulley material and a finished product showing still another embodiment of the present invention. 1, 1', 1//...Pulley material, 2, 7, 1
...Large diameter part, 3, 3', 3ku...Medium diameter part,
4, 4', 4''---small diameter part, 11, 1V, 11
″...(Small diameter) V groove, 20, 2σ, 20k...
...(Large diameter) V groove, 5, 6, 12, 14, 17, 18
...Rotational mold, 8, 10, 15, 19...
...V-groove forming roller.

Claims (1)

[Claims] 1. Molding a stepped cup-shaped pulley material with at least large, medium, and small diameter portions on the peripheral wall, loading this pulley material between upper and lower rotary molds, and applying compressive force in the axial direction to the peripheral wall. A V-groove forming roller that rotates while applying force and presses the outer surface of the peripheral wall from the radial direction is pressed sequentially from the small diameter side to the small diameter part and large diameter part of the pulley material. A method for manufacturing a multistage V pulley, characterized by forming V grooves.