Patent ID: 8042240

Claim:
A machine tool comprising: a machining unit fixed to a frame; a base plate movable along a rail on the frame, for moving a work piece toward and away from the machining unit; an intermediate plate movable along the rail between the machining unit and the base plate, for pushing a reference plane of the work piece set on the base plate and positioning the work piece in a machining position; a lower plate disposed between the base plate and the intermediate plate, the lower plate having a lower plate concave spherical surface receiving portion; a lower convex spherical surface receiving portion disposed between the lower plate and the base plate, the lower convex spherical surface cooperating with the lower plate concave spherical surface receiving portion to tiltably connect the lower plate to the base plate; a pair of upper plates disposed between the lower plate and the intermediate plate, each of the upper plates defining an upper plate concave spherical surface receiving portion; and a pair of upper convex spherical surface receiving portions disposed between the lower plate and the respective upper plates, the upper convex spherical surface receiving portions cooperating with the upper plate concave spherical surface receiving portions to tiltably connect the respective upper plate to the lower plate.