抄録
A thin ultrasonic motor for driving date dials of calendar in watches has been developed. The thickness of the motor is one-fourth of conventional motors for watches, and its output torque is 100 times larger. This new motor was installed in the new product called "KINETIC perpetual calendar Cal. 7D". This product has the following characteristics. a) Automatic correction of year-month and 2figure big-date indication calendar at the end of every month. b) High speed calendar drive by high torque ultrasonic motor.
