Method for manufacturing transmittion bearing retainer

Abstract

Disclosed is a method for manufacturing a transmission bearing retainer. The method includes a step of forming a bolt hole at the bearing retainer, wherein the bolt is inserted into the bolt hole. The step of forming the bolt hole includes: a step of forming a holt base hole of the bolt hole through piercing of a press working method; a step of forming an expanded hole through a first cold forging of the press working method, wherein a bolt head of the bolt being in contact with the expanded hole; and a step of forming anti-rotation grooves on a surface of the expanded hole through a second cold forging.

Description

TECHNICAL FIELD[0001]The invention relates to a method for manufacturing a transmission bearing retainer, more particularly, to a method for manufacturing a bearing retainer fixing a bearing supporting a shaft in a transmission so that the bearing does not move in an axis direction. In the method, dimensional accuracy of a portion where a bolt head of a bolt is coupled can be enhanced, and the bolt head of the bolt fixing the bearing retainer can be stably fastened to, close-contacted to, and assembled with the bearing retainer by minimizing a surface polishing process and maximizing a surface roughness. Accordingly, a formation of a gap at portion where the bolt head is in close contact, oil flow in the gap, vibrations of bolt, and a reduction of a fastening force can be effectively prevented.BACKGROUND ART[0002]A transmission is a device for matching running conditions by changing a reduction ratio of a vehicle engine. Various kinds of transmissions (such as a manual transmission,...

AI Technical Summary

Benefits of technology

The invention provides a method for manufacturing a transmission bearing retainer with a new shape that effectively fixes the bearing retainer to a bolt and prevents bolt loosening. This method uses a press working method instead of cutting to form bolt holes, which increases surface roughness and minimizes surface polishing. Anti-rotation grooves are formed on the surface of an expanded hole to increase friction between the bolt head and the expanded hole, preventing bolt loosening. This method prevents gaps, oil flow, and bolt loosening. Other unmentioned technical problems include preventing bolt loosening and increasing friction between the bolt head and the expanded hole.

Problems solved by technology

Although a surface polishing process such as buffing is conventionally performed after machining, it is difficult to completely process the protrusions and / or identifications at the surface 236 of the expanded hole 232 formed during the cutting work due to limits of cost and time in the surface polishing process.

Therefore, plating or using an adhesive agent is restricted when the components used for the transmission are manufactured and assembled.

For such a reason as mentioned, in bearing retainer fixed to the case by a bolt in the case of the transmission, if there is a thin gap between contact surfaces of the bolt and the bearing retainer, the oil may be continually leaked, the bolt may be loosened, and a fatal defect may be generated (in the case that the bolt is loosened, the bearing may move and the bearing may be hung on a gear, thereby making the change of speed impossible).

That is, in the conventional bearing retainer 200 of the transmission, since it is difficult to completely eliminate the minute protrusions and / or identifications at the bolt hole 230 (specially, the expanded hole 232 that the bolt head is in close contact with) formed by the cutting working, it may cause the fatal defect of the transmission by the loosening of the bolt.

Images