REVOLVING CLAMP CYLINDER

Japanese Patent JP3794558

B2

PROBLEM TO BE SOLVED: To provide a revolving clamp cylinder with a revolving motion generating mechanism prevented from being damaged. SOLUTION: When the revolving motion of a clamper 17 tending from an unclamp position A to a clamp position is precluded during revolution, dangerous overtorque exceeding allowable torque is generated in an intermediate member 56 such that a revolution groove 55 forces a guide ball 62 to revolve with a piston 13 being moved further downward by fluid pressure. The generation of the dangerous torque causes the intermediate member 56 to be pushed down to a head side against the spring force of a disc spring 69, followed by disengagement between a V-groove 67 and an engaging/disengaging ball 68 which are normally in mesh with each other and the free rotation of the intermediate member 56. Thus, the revolving motion generating mechanism 63 is prevented from being damaged by the free rotation of the intermediate member 56 holding the guide ball 62 due to the unreasonable torque.