Patent attributes
A linear drive ultrasonic motor includes at least an ultrasonic vibrator having a piezoelectric element, a driven member which is driven by a frictional force between the ultrasonic vibrator and the driven member, a pressing member which presses the ultrasonic vibrator such that a frictional force is generated between the ultrasonic vibrator and the driven member, a rolling member having a spherical shape, which makes a contact with the driven member, and a base member which movably supports the driven member via the rolling member. The rolling member makes a contact with the base member at a first contact point, and makes a contact with the driven member at two second contact points. Lengths of two straight lines which connect the first contact point and the two second contact points are substantially same.
