ラック形工具による平歯車の冷間転造 : 二段転造における転造代

Abstract

In the full-form rolling on one step, it is fallen short of their expection to produce the rolled profiles precisely. Then, the double rollings (rough and finish) are desirable operations for rolled gears made by means of rack dies. In the first rough rolling, the profile of die tooth is modified slightly in due consideration of the effect of the after rolling. In the finish rolling, the rolled gear blank which has the 28 teeth of module 1.5,the pressure angle of 25° and the whole depth of 2.7 mm is rolled again by the finishing rack dies. During rolling, the work-piece mounted on the unrestrainted arber is rotated between two dies. And, these dies are each associated with a separate slider incorporating a hydraulic drive. The investigation of those finished rolling conditions revealed that the accuracy of rolled teeth was controlled by both the die shape at the rough rolling and the amount of the deviation from the normal profile of the pre-rolled pinion. That is, the desirable modifications on the die profiles were decided and the order of deviation required was cleared to be within 0.04mm in maximum, and the rolled profiles were improved.