MANUFACTURING METHOD AND APPARATUS FOR SHELL OF UNIVERSAL-JOINT

摘要

Manufacturing method for a tubular shell of a constant velocity universal-joint for flexibly coupling two rotary shafts, to one of which the shell is fixed at a flange thereof. The method comprises a groove and preliminary flange forming process and a flange forming process. In the former process a hollow cylindrical blank is applied pressing in a radial direction for forming plural grooves therein and forming at the same time a preliminary flange at one end of the cylindrical blank by expanding it into a funnel shape, and in the latter process the preliminary flange formed on a semi-finished article in the former process is formed into a completed flange by a flange forming die, while holding the semi-finished article in a restrained status under pressure from either side, external and internal, by means of restraining dies. An apparatus suitable for performing the method is also disclosed.