External swing-rotating clamp, cam actuated

When the clamp post moves upwards from clamping position, the dowel pin on the bushing cinches the cam and rotates the post. The swinging arm mounted on the clamp post retracts from the clamping surface and rotates about 60°, permits this way to remove the workpiece. After we replace the workpiece and pull down the clamp post. The swinging arm rotates in its clamping position and clamps the workpiece.
Because of the retracting movement, the helix angle of the cam on the clamp post must be large, about 45°, and there must be considerable space at both ends of the cam groove in order to clamp and unclamp freely.