MEANS TO MANUFACTURE STEERING RACK BARS

摘要

A die (22) for forming the toothed end of a steering rack bar from a cylindrical blank by forging comprising first and second die blocks (21, 22) adapted to converge on the blank. The die blocks incorporate opposed semi circular recesses to accommodate the blank, one recess incorporating the obverse form of the teeth, the recesses defining a main cavity (23) as the die blocks converge to their final position. Subsidiary recesses in the die blocks at the joint line there between define chambers (24), each side of the main cavity communicating with one of the chambers along the longitudinal extent of the main cavity. The chambers in cross section incorporate stop means (29) located remote from the main cavity (23) restricting further flow of blank material away therefrom. The chamber volume at the final position is equal to the difference of volume between the rack bar blank and the steering rack bar as finish forged over the toothed end thereof.