CLAMP DEVICE FOR JIG

PROBLEM TO BE SOLVED: To provide a clamp device for jigs preventing interference with a welding gun even when the welding gun is moved along the peripheral part of a work W1. SOLUTION: A clamp cylinder 71 is arranged on a jig 1 so that the cylinder falls within the plane of projection (the plane of projection of the work) in the vertical direction of the work W1 and the axial line of the cylinder is inclined obliquely upward toward the outside of the plane of projection of the work. A clamp arm 70 is connect to a clamp cylinder 71 so as to be linearly moved in the direction of the axial line of the cylinder and also a pawl part 70b which is bent to the side of the clamp cylinder 71 is formed in the tip part of the clamp arm 70 while allowing an upward rising part 70a to exist therein. When the clamp arm 70 is moved on a closed side where the arm approaches the clamp cylinder 71, the pawl part 70b enters in the plane of projection of the work and brought into contact with the top of the peripheral part of the work W1. When the clamp arm 70 is moved on a opened side where the arm is away from the clamp cylinder 71, the pawl part 70b is made to be detached outside the plane of projection of the work.