JP2548048B2 - Clutch drum manufacturing method - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of manufacturing a clutch drum used in a planetary gear type automatic transmission or the like, the outer peripheral surface of which serves as a sliding contact surface of a brake band.

[0002]

2. Description of the Related Art Conventionally, in this type of clutch drum, JP-A-55-40365 and JP-A-1-250.
As disclosed in Japanese Laid-Open Patent Publication No. 623, a spline forming member press-molded in a bottomed cylindrical drum body having an outer peripheral surface formed on a sliding contact surface of a brake band is welded, and a clutch disc is spline-engaged with the member. I am trying to let you.

[0003]

In the above-mentioned prior art, since the spline forming member, which is separate from the drum main body, is welded to the drum main body, the number of parts is increased, resulting in an increase in cost and weight. In view of the above points, an object of the present invention is to provide a method for manufacturing a clutch drum, which does not require a spline forming member and can achieve cost reduction and weight reduction.

[0004]

In order to achieve the above object,
The method of the present invention, on the inner peripheral surface of the bottomed cylindrical drum body,
The step of forming the spline groove for spline-engaging the clutch disc by half-punching the peripheral wall portion of the drum body from the inner peripheral side to the outer peripheral side, and the convex portion protruding to the outer peripheral side of the drum body by this half-punching processing It is removed by cutting, and the outer peripheral surface of the drum body is formed on the sliding contact surface of the brake band.

[0005]

The spline groove is formed by the recessed portion left on the inner peripheral surface of the drum body, and the clutch disc can be spline-engaged with the drum body without welding a separate spline forming member to the drum body. In addition, even if the convex portion on the outer peripheral side of the drum body is cut and removed, the peripheral wall portion of the drum body is only half cut out, so there is no hole in the peripheral wall portion and the outer peripheral surface of the drum body is It can be formed into a required cylindrical surface required as a sliding contact surface of the brake band.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring to FIGS. 1 and 2, reference numeral 1 designates a drum main body made of a sheet metal press-molded into a bottomed cylindrical shape. Using a press working apparatus having a plurality of punches A that can move back and forth, half blanking is performed from the inner peripheral side to the outer peripheral side as shown in FIG. 1B, and the half blanking remaining on the inner peripheral surface of the drum body 1 is performed. The trace recesses form a spline groove 3 for spline engaging a clutch disc (not shown). As the press working device, a conventionally known one can be used, such as JP-B-62-35528.

During the half blanking, the convex portion 4 corresponding to the spline groove 3 is projected on the outer peripheral side of the peripheral wall portion 2 of the drum body 1. The convex portion 4 is removed by cutting in the next step of the half blanking, As shown in FIGS. 1 (c) and 2 (c), the outer peripheral surface of the drum body 1 is finished into a cylindrical surface, and the outer peripheral surface is formed as a sliding contact surface 5 of a brake band (not shown).

[0008]

As is apparent from the above description, according to the present invention, a spline groove is formed on the inner peripheral surface of the drum body whose outer peripheral surface is the sliding contact surface of the brake band, and the clutch is formed in the spline groove. The disc can be spline-engaged, and it is not necessary to weld a spline forming member separately formed on the drum main body, and the number of parts can be reduced, cost can be reduced, and the weight of the clutch drum can be reduced.

[Brief description of drawings]

FIG. 1 is a cutaway front view of a clutch drum showing a manufacturing process of the present invention.

FIG. 2 is a cutaway side view of a clutch drum corresponding to FIG.

[Explanation of symbols]

1 drum body 2 peripheral wall 3 spline groove 4 convex 5 sliding surface

Claims (1)

(57) [Claims] 1. A method of manufacturing a clutch drum, wherein an outer peripheral surface is a sliding contact surface of a brake band, wherein a spline groove for spline-engaging a clutch disc is formed on an inner peripheral surface of a bottomed cylindrical drum body. The process of forming the peripheral wall part of the main body from the inner peripheral side to the outer peripheral side by half blanking, and by this half blanking, the convex parts protruding to the outer peripheral side of the drum main body are removed by cutting, and the outer peripheral surface of the drum main body And a step of forming on the sliding contact surface of the brake band.