method for the manufacture of a hollow shaft, in particular camshaft and then manufactured hollow shaft

摘要

Hollow shafts, and particularly camshafts, are produced using an internal high-pressure forming (IHF) process. Cams and/or machine elements are mounted at intervals onto the outer surface of the hollow shaft, depending on the use of the latter, by a non-positive and/or positive fit, in a position appropriate to their function when the hollow shaft is placed in the forming tool. An element with approximately the same external diameter as the internal diameter of the hollow shaft is placed in at least one of the hollow shaft, and the hollow shaft together with the cams and/or machine elements that have been pushed onto the same and the inserted element are placed in an IHF tool. Once the IHF tool is closed, the medium is caused to act under the required high-pressure in the hollow shaft. At the same time as the medium is acting internally, at least one ram is pressed axially against at least one front face of the hollow shaft. Thus, filling the IHF mould with a material flow induced by the pressure effect of the medium and the mechanical pressure of the ram. The element is thus enclosed by the material of the hollow shaft and the cams and/or elements are connected to the hollow shaft by the non-positive and/or positive fit by means of the expansion of the hollow shaft. The end of the hollow shaft sealed by the element is mechanically machined to suit functional requirements.