Patent ID: 7144005

Claim:
A clamping device for clamping a workpiece between a clamping arm and an opposed clamping member by rotating the clamping arm supported for rotating on a body and applying a clamping force to the clamping arm, the device comprising: a worm driving source, and a worm to be driven by the worm driving source, for rotation about an axis on the body; a worm wheel provided to a periphery of a rotating shaft of the clamping arm and engaged with the worm; and a clamping force applying mechanism to be actuated in response to contact of the clamping arm with the workpiece supported by the clamping member to apply an axial force in a direction of the axis to the worm rotation of which has been stopped by the contact, wherein the clamping arm is rotated by driving of the worm for rotation and the axial force applied to the worm by the clamping force applying mechanism acts on the worm wheel as a pressing force in a direction of a tangent to the worm wheel to apply the clamping force to the clamping arm.