JPH049243A - Production of rotating body - Google Patents

Abstract

PURPOSE:To improve strength and dimensional accuracy and to obtain a rotating body which can be reduced in weight by curving a disk-shaped sheet to a spherical surface shape, forming an annular thick part on an outer peripheral side and forging and molding an externally toothed gear by a die for externally toothed gear in the outer peripheral part of the thick part. CONSTITUTION:The disk-shaped thin steel sheet is curved and formed to the spherical surface shape to obtain a molding 2. The molding 2 is inserted into a lower die 3 which regulates an outer peripheral end by closely fitting an outer peripheral part. The central part of the molding is pressed by a circular cylindrical upper die 4 and a slack part is molded to an annular shape. The slack part on the outer side of the upper die 4 is pressed by the annular upper die 6. The molding 8 formed with the annular thick part 7 is obtd. on the outer side of the disk-shaped part 6. The thick part 7 is pressed and bent downward by an annular pressing and bending die 10. The disk part 6 is pressed by the upper die and the externally toothed gear 15 is molded at the outer peripheral part of the thick part 11 by the die 14 for the externally toothed gear.

Description

Detailed Description of the Invention [Industrial Application Field] The present invention relates to a rotating body, particularly a disc-shaped rotating body that is thick at the outer peripheral part and has an external gear or an internal gear in this part. The present invention relates to a method of manufacturing a body.

[Conventional technology]

An example of the above-mentioned rotating body is an automobile flywheel. Conventionally, this type of rotating body is manufactured by forging or cutting out the thick part a on the outer periphery to form a gear shape, as shown in Fig. 22. A separately molded disc member is attached to this by welding, caulking, press-fitting, etc. to attach it to the rotating shaft, and after finishing it, external teeth are attached to the outer periphery. C is processed by gear cutting.

[Invention or problem to be solved]

In the above-mentioned conventional manufacturing method for a rotating body, many steps are required to make the material for the rotating body, such as forming the outer peripheral part a and the disc part in separate processes and joining them in separate processes. The gears on the outer periphery had to be machined, resulting in high processing costs.

In addition, by joining different parts to the outer circumferential part and the disc part,
The strength and precision of this joint are a problem, and the thickness of the outer periphery cannot be made thinner to prevent distortion due to welding, which poses a problem in terms of weight reduction.

The present invention has been developed in consideration of the above-mentioned problems, and by using only forging in the manufacturing process and integrally molding, processing costs can be reduced, and by using a disc-shaped thin plate as the molding material, The material cost can be lowered, and the outer peripheral part and the disc part are integrally molded, and
The purpose of the present invention is to provide a method for manufacturing a rotating body in which the gears on the outer periphery are also forged, thereby improving the strength and dimensional accuracy of each part, as well as reducing the weight by reducing the thickness of the outer periphery. That is.

[Means to solve the problem]

In order to achieve the above object, the method for manufacturing a rotating body according to the present invention involves bending a disc-shaped thin plate into a spherical shape, and then pressing the central part with the outer peripheral part regulated in the radial direction. to form an annular slack part on the outer periphery of the central pressing part, and then press this slack part with an annular mold or roller to form an annular wall thickness on the outer periphery of the central pressing part. Then, this thick part is bent in the axial direction with respect to the central pressing part, and an external gear is forged on the outer periphery of the bent thick part using an external gear mold.

Further, an internal gear may be formed by forging inside the folded and formed thick part.

At this time, while bending the thick part in the axial direction with respect to the center part, an external gear or an internal gear may be press-formed on the outer or inner peripheral part of the thick part.

[For production]

The material consisting of a disk-shaped thin plate is formed into a spherically curved primary molded body, and then formed into a secondary molded body having a central pressing part and a thick part on the outer periphery of this pressing part. A tertiary molded body is formed by bending the thick part of the mold in the axial direction with respect to the central part. Then, an external gear is formed on the outer periphery of this tertiary molded body using an external gear mold, or an internal gear is formed on the inner periphery of this thick walled part.

At this time, when the tertiary molded body is molded, an external gear or an internal gear may be molded at the same time.

〔Example〕

Embodiments of the present invention will be described based on the drawings.

First, a material 1 made of a disc-shaped thin steel plate as shown in FIG. 1 is curved into a spherical shape as shown in FIG. 2 to obtain a primary molded body 2. Next, as shown in FIG. 3, the primary molded body 2 is inserted into the lower mold 3 with its outer periphery fitted without any gap and the outer peripheral edge regulated, and the central part of the primary molded body 2 is inserted into the lower mold 3. is pressed with a cylindrical upper mold 4. As a result, as shown in FIG. 4, a slack portion 5 is formed into an annular shape at the portion of the dimensional difference between the lower mold 3 and the upper mold 4. Next, as shown in FIG.
While pressing, the outer slack portion 5 of the upper mold 4 is pressed by the annular upper mold 6.

In the above process, the slack portion 5 is pressed flat as shown in FIG. 6, and a secondary molded body 8 in which an annular thick portion 7 is formed on the outside of the disk portion 6 is obtained.

Next, as shown in FIGS. 7 and 8, the secondary molded body 8 is placed on a table 9 having a diameter smaller than that of the disc part 6, and the thick part 7 is pressed into an annular press-bending mold 10. Press down and bend.

As a result, as shown in FIG. 8, a tertiary molded body 12 having an annular thick portion 11 on the outer peripheral side of the disk portion 6 is formed.

Next, as shown in FIG. 9(A), this tertiary molded body 12 is
While fitting into the lower mold 13, the disc part 6 is held down by the upper mold, and in this state, the outer peripheral part of the thick part 11 is fitted with the mold 14 for an external gear formed in the shape of an internal gear. Both external gears 15 as shown in FIG. 9(B) are formed.

At this time, if any excess material is generated due to the molding of the external gear 15, this excess material is released to the lower end and radially outward. These are removed in post-processing.

FIG. 10(A) shows the molding of the external gear 15 in which the excess metal is released in the axial direction, and the lower mold 13
An external gear 1 as shown in FIG. 10(B) is formed by providing an annular recess 16 for releasing the excess material, and allowing the excess material to escape from the molding.
5' is formed.

In each of the above steps, as shown in FIG. 14, the pressure on the slack portion 5 when obtaining the secondary molded body 8 is applied several times while being backed up by an annular upper mold 6' that gradually descends while rotating. The thick portion 7 may be formed by crushing with the roller 17.

Furthermore, in the above embodiment, the external gear mold 14' is provided on the inner surface of the press-bending die 10', and the external gear 15, 15' is molded as shown in FIG. The external gear 1515' may be formed simultaneously with the pressing and bending of the thick portion 7 by lowering the mold 10'.

12 and 13 show a specific example of a method for molding the external gear 15, 15' at the same time as pressing and bending the thick wall portion 7. 2 at 17
Next, the molded body 8 is pressed and molded. At this time, by providing an arcuate portion 18 at the inner diameter entrance of the external gear mold 14', gear molding in this step is facilitated.

In each of the above embodiments, an example was shown in which an external gear is formed on the outer periphery of the thick wall part, but as shown in FIGS. 15 to 20, an internal gear is formed on the inner periphery of the thick wall part by forging. It may also be molded.

That is, as shown in FIG. 15, the thick part 7 of the secondary molded body 8 is pressed and bent in the direction opposite to that shown in FIG. 3 for internal teeth shown in
Next, the molded body 12' is molded, and an internal gear 25 is molded onto the inner circumferential portion of the thick wall part using an internal gear mold 20, as shown in FIGS. 17 and 18.

At this time, the molding of the tertiary molded body 12' is facilitated by providing a slope 21 on the lower surface of the press-bending die 19', as shown in FIG.

FIGS. 20 and 21 show an example of forming an internal gear at the same time as pressing and bending the thick wall part, in which the secondary formed body 8 is placed on the guide part 23 of the lower die 22, and Press the mold 24 for the internal gear.

As a result, the thick portion sinks into the tooth profile of the internal gear mold 24, and the internal gear 25 is molded.

Although SF6 material was used as the molding material in the above embodiment, it may also be a light alloy such as A1.

〔Effect of the invention〕

According to the present invention, processing costs can be reduced by integrally molding using only a forging process in the manufacturing process. Furthermore, a disk-shaped thin plate can be used as the molding material, and the material cost can also be reduced. Furthermore, the thick outer peripheral part and the plate-shaped disc part are integrally molded, and
By also forming the gear on the outer periphery, the strength and dimensional accuracy of each part can be improved, and the wall thickness of the outer periphery can be made thinner, thereby reducing the weight.

[Brief explanation of drawings]

Figures 1 to 21 show examples of the present invention, with Figure 1 being a perspective view showing the raw material, Figure 2 being a perspective view showing the primary molded product, Figures 3 and 4, Fig. 5 is a process explanatory diagram showing the forming process of the secondary formed body, Fig. 6 is a sectional view showing the secondary formed body, and Figs. 7 and 8 are process explanatory views showing the forming process of the tertiary formed body. , Fig. 9 (A), (B), Fig. 10 (A), (B)
11 are process explanations and cross-sectional views of molded products showing different embodiments of the external gear molding process, FIG. 11 is a process explanatory diagram showing different embodiments of the external gear molding process, FIGS. 12 and 13
Figures are other process explanatory diagrams, Figure 14 is a process explanatory diagram showing different forming processes for the secondary molded body, Figures 15 to 18 are process explanatory diagrams showing the internal gear forming process, and Figure 19 is a process explanatory diagram showing the forming process of the internal gear. A sectional view showing the other side of the example shown in FIG. 15, and FIGS. 20 and 21 are process explanatory views showing different embodiments of the internal gear forming process. FIG. 22 is a sectional view showing a rotating body manufactured by a conventional manufacturing method. 1 is the raw material, 2 is the primary molded body, 5 is the slack part, 6 is the disc part, 7 and 11 are the thick parts, 8 is the secondary molded body, 12.21'
15 is an external gear, and 25 is an internal gear.

Claims (3)

[Claims] (1) After curving a disc-shaped thin plate into a spherical shape, press the center part with a press die while restricting the outer circumference in the radial direction. A slack part is formed, and then this slack part is pressed with an annular mold or a roller to form an annular thick part on the outer periphery of the central pressing part, and then the thick part is pressed against the central pressing part. 1. A method for manufacturing a rotating body, comprising: bending the rotary body in the axial direction, and press-forming an external gear on the outer periphery of the bent thick wall part using an external gear mold. (2) The method for manufacturing a rotating body according to claim (1), wherein the internal gear is press-formed on the inside of the bent thick-walled part. (3) A claim characterized in that an external gear or an internal gear is forged on the outer or inner periphery of the thick part while simultaneously bending the thick part in the axial direction with respect to the central part. 1), the method for manufacturing a rotating body described in (2).