Tightening Method of Miniature Screw Threads with Ultrasonic Vibration

- Effect of Amplitude of 60 kHz Longitudinal Vibration -

Abstract

This paper describes the effect of amplitude of longitudinal ultrasonic vibration on tightening miniature screw threads in terms of tightening torque, bearing surface friction torque and thread torque. Miniature screw threads of S1.4 are tightened with the ultrasonic vibration of 4 different amplitudes of 60 kHz longitudinal vibration. The experimental results indicate that the amplitude of 2.6μm reduces the tightening torque by 25%. In the case of the amplitude of 1.8μm, the largest depression of the contact surface of specimen was formed. These experimental results suggest that the amplitude of vibration should be optimized.