MOVABLE BODY DRIVE DEVICE

摘要

PROBLEM TO BE SOLVED: To provide a movable body drive device that can ensure high precision positioning. SOLUTION: The movable body drive device linearly moves a table member 7 simultaneously by means of nut members 5a and 5b fixed to both sides thereof and two screw shafts 4a and 4b. The screw shafts 4a and 4b and the nut members 5a and 5b are in threaded engagement via ball members 6a and 6b seated between thread ridges of the screw shafts 4a and 4b respectively. The screw shaft 4a has a portion where the ball members 6a abut a surface of the nut member 5a (an arrow A in the figure) opposite to an oscillatory wave motor, and the screw shaft 4b has a portion where the ball members 6b abut a surface of the nut member 5b (an arrow B in the figure) on the side of the oscillatory wave motor. Opposite directions of thrusts acting on the screw shafts 4a and 4b under regulation by the nut members 5a and 5b substantially completely regulate a backlash of the table member 7 as a whole in the movement direction.