The structures of the parallelogrammechanism cradle head, forearm 1 cradle head and arm cradle head are the same.
平行四边形转动关节、小臂一转动关节、大臂转动关节结构相同。
2
Automatic opening function is realized by contra - parallelogrammechanism. Optimal kinematic scheme is obtained by the kinematic and mechanical analysis of the contra-parallelogram.