3D tube forming and applications of a new bending machine with hydraulic parallel kinematics

This research presents a new versatile bending machine and its practical applications. The proposed machine uses a new method. When tubes are fed into the fixed and mobile dies, they are bent by shifting the relative position of the mobile die. The bending radius is controlled by the relative distance and orientation between the mobile die and the tube. The bending angle is controlled by the length of the fed tube. This forming process has a big advantage. A change in the expected bending shape will need no change in the tooling system but only a new definition of the motion of the active die and the length of the fed tube. Active die movements are controlled by a 6-DOF Parallel Kinematics Mechanism (PKM) with a hydraulic servo drive. Making use of the hydraulic PKM serves not only to achieve a complete motion along six axes but also to obtain the high dynamic motion of the bending machine. Application examples show that the bending machine can be applied to a designer's furniture and universal designed products. Until now, these processes have been difficult to achieve using a conventional bending machine.