Property-controlled, rotationally superimposed fine blanking of helical gears (2D-Blanking)

In contrast to helical gears, fine blanking of spur gears is already state of the art. For the production of helical gears, the Laboratory for Machine Tools and Production Engineering (WZL) has pursued in preliminary work approaches by fine blanking with passive mechanical rotational superposition. However, the sheared surface quality showed high die roll and fracture zone. Elastic deformation of the cutting punch due to the application of transverse force and a one-sided unfavourable stress-strain condition in the shear zone were identified as the cause.

To improve the sheared surface quality, the cooperation project 2D-Blanking therefore aims at an active, loop-controlled rotation with servomechanical drive and an integrated tool lubrication to influence the stress-strain condition in the shear zone. The WZL analyses the interactions between rotation, lubrication and sheared surface quality characteristics for process design with FE-simulations and develops a control system in cooperation with the Institute of Automatic Control (IRT) of the RWTH Aachen University. Based on this, a fine blanking tool is then developed, designed and manufactured by Precision Resource Canada LTD and a tool lubrication system by Raziol Zibulla & Sohn GmbH. Finally, the tool concept will be validated experimentally in cooperation with all involved partners.