ONE-PIECE HOLLOW CAMSHAFT AND PROCESS FOR PRODUCING IT

摘要

The invention relates to a hollow camshaft consisting of a metal or metal alloy or plastic which can be cold-formed and heattreated and has a fiber flow parallel to the exterior contours of the camshaft, and to a method for producing it comprising the steps of: - Placing a pipe outlet element and filling it with fluid; - Sealing at least the pipe section to be widened; - Applying an internal high pressure suitable for widening the pipe section to produce an intermediate product preform, wherein, while the internal high pressure is applied, the hollow pipe is compressed against a movable die in the direction of its long axis in such a way that accumulations of material occur at approximately those places where it is intended to create cams; - Shaping the intermediate product pre-form into a shape corresponding to a final camshaft shape by means of the internal high pressure shaping method, so that cams are shaped at the desired locations; - If necessary, finishing the cams by heat-treatment or the like.