Rotary motion feedthrough using ultrasonic motor for high vacuum condition

A vacuum environment is indispensable for various measurement devices. To improve these devices, the mechatronics systems for vacuum conditions should be advanced. An ultrasonic motor has many advantages, and is suitable for achieving vacuum conditions. However, the piezomaterial may be a source of outgas and may hinder the baking treatment. Therefore the piezoelectric part is arranged outside the vacuum chamber. The driving mechanism is a mode-rotation motor. The stator transducer was a bolted Langevin vibrator for generating bending vibration. This motor was successfully operated under a vacuum condition of 2/spl times/10/sup -6/ [Pa]. The endurance of the motor and the change of the vacuum level were measured and discussed.