method and device for the production of nebenformelementen

摘要

The invention relates to a method and a device for producing secondary form features on a circumferentially closed hollow profile. The device comprises an internal high pressure forming tool, into the impression of which a hollow profile blank can be inserted, a branch branching off radially from the impression, into which branch the hollow profile blank can be expanded by means of a fluidic internal high pressure, with the secondary form feature being formed. So that secondary form features configured in virtually any desired manner from the point of view of the form profile can be formed on the hollow profile in a simple manner and in a reliable manner in terms of the process, it is proposed that the device, furthermore, comprises a diaphragm and a pressure generator, by means of which pressure can be applied to the diaphragm via a pressure medium in such a way that the diaphragm, during the expansion, bears in a supporting manner against the forming secondary form feature against the expansion direction. The diaphragm gives way elastically with the progress of the forming of the secondary form feature until the final shape is achieved. In this case, the diaphragm is attached to the tool in such a way as to span the branch outside the longitudinal extent of the impression.