抄録
It is known by past researches on the loosening of a screw that rotation of loosen will arise if the radius direction vibration is given to a bolt head or the bearing surface of a nut. On the other hand, it is known that it is effective in ultrasonic vibration reducing apparent friction, and the method of performing screw tightening with little variation is also studied, it is performed by tightening with the ultrasonic vibration of the direction of the axis to a bolt head or a nut. In this research, the bolt head or the nut was fastened with radial ultrasonic vibration, and it is investigated about the effect.
