基于并联机构的多夹钳柔性拉形机的设计

Design of multi-gripper flexible stretch forming machine based on parallel mechanism

针对传统拉形机在成形双曲率蒙皮零件时,易产生不贴模、拉裂或起皱等缺陷,基于并联机构拓扑结构理论设计了一种并联多夹钳柔性拉形机。首先,介绍了并联多夹钳柔性拉形机及其辅助装置的结构,对拉形机并联支撑机构进行结构设计与自由度计算;其次,运用ADAMS软件对并联支撑机构进行运动学仿真,对拉形机的并联输出板的位移变化与速率变化曲线进行分析,验证了并联多夹钳柔性拉形机并联支撑机构的稳定性;最终,通过有限元法分析拉形件在不同拉力下的应变云图,验证了并联拉形机拉形方式的合理性。

For the defects of no attaching-die, crack or wrinkle produced easily in forming the double curvature skin parts by traditional stretch forming machine, a paraUel multi-gripper flexible stretch forming machine was designed based on the theory of parallel mechanism topology. First, the structure of the parallel multi-gripper flexible stretch forming machine and its auxiliary device were introduced, and the structural design and calculation of degrees of freedom for the parallel support mechanism were conducted. Then, a kinematics simula- tion for the parallel supporting institution was implemented by the ADAMS, and the stability of parallel support mechanism was verified by analyzing the displacement change and rate change curves of parallel output board. Finally, the feasibility of stretch forming method was verified by FEA analysis strain distribution under different tensions in the panel.