Development of Incremental Sheet Metal Forming System Using Elastic Tools : Principle of Forming Process and Formation of Some Fundamentally Curved Shapes

A new process of sheet metal forming by which various curved shells are formed without the need for any expensive dies was proposed. In this process, a small area in the sheet metal blank is pressed between a pair of rigid or elastic standard tools which have a simply-shaped head such as a hemispherical or hemicylindrical one. This local forming operation is repeated incrementally over the entire blank. As a result, the blank can be formed into various shapes. To realize the forming process, a computer-controlled forming machine was designed and manufactured. Forming processes for spherical, ellipsoidal and hyperboloidal shapes were examined, and these fundamental shapes were successfully formed with good geometric accuracy and surface appearance. The effects of the forming paths and parameters on the product shape were investigated.