Study on dynamic characteristic and forging capacity of the direct drive press with symmetrical toggle booster mechanism driven by TPMLM

Compared with the conventional servo press, the direct drive press even has no transmission mechanism, so it has advantages in controllability, precision and energy management. But, the forging capacity of the direct drive press is limited by the power of the linear motor. In this paper, a novel press driven by a tubular permanent magnet linear motor (TPMLM) is presented, and a symmetrical toggle booster mechanism is specially proposed to enhance the forging capacity. The mathematical model of the toggle booster mechanism is established, The TPMLM is designed, and the experimental prototype of the novel press is manufactured. The forging capacity and dynamic characteristics of the press are studied theoretically and experimentally. The results show that the introduction of the symmetrical toggle booster mechanism enriches the dynamic characteristic curve of the press and enhances the forging capacity. Therefore, the structural parameters of the toggle mechanism and the working position of the slider can be adjusted to meet different technological requirements. In addition, based on the research work, three directions are proposed to improve the forging capacity of the novel press. The research contributes to the performance optimization and development of direct drive press.