Fabrication process for hollow shafts for motor vehicle drive trains uses solid blank to cold-form end and neck sections with serration toothings, and apply low-friction coating

摘要

A cylindrical blank (40) of solid material is cold-formed (41) to give it an end section (41a) with end diameter, and a neck section (41b) with a smaller diameter. The end section is cold-formed to create a number of serration toothings (42) around its circumference. The serrations extend in size from a diameter smaller than the end diameter of the blank, to a diameter larger than the end diameter. The toothings are formed by rolling and are given a cross sectional profile in the shape of an involute. The neck section of the blank and the toothings are coated by a conventional material with low friction coefficient.