A deforming tool for forming an elongated deformation in a planer workpiece includes cooperating upper and lower parts, a roller ball being mounted in one of the parts and cooperating with a mating element in the other part, the workpiece being engaged above and below by the two parts. The roller ball...http://www.google.de/patents/US6131430?utm_source=gb-gplus-sharePatent US6131430 - Tool and method for the rolling treatment of a workpiece
