System Design and Experimental Research on the Tangential Ultrasonic Vibration-assisted Grinding Gear

Abstract Gear plays an important role in transmitting motion and power system, and a new promising process should be utilized to enhance the machining accuracy and performance. In this paper, the ultrasonic vibration was superimposed into the gear to carry out the tangential ultrasonic vibration-assisted grinding gear (TUVAGG). The longitudinal resonant vibration system was designed based on the non-resonant theory. Firstly, the gear was simplified into a disc with the diameter of the reference circle, and the dynamic equation of each part was erected respectively. Then the frequency equation was derived according to the coupling conditions of the force and displacement during the combined surface of the vibration system. Simultaneously, the characteristic of displacement for the vibration system was also obtained. Secondly, the vibration system composed of the simplified disc and the gear was simulated by the finite elements analysis method, and verified by the resonant measurement experiment respectively. The measurement results exhibited a good agreement with the theoretical. Finally, the effectiveness of the vibration system was verified through the ultrasonic vibration-assisted grinding gear test. It was found that compared with the conventional grinding gear (CGG), the normal grinding force and tangential grinding force was reduced by 7.4-28.2% and 8.9-18.9% respectively during TUVAGG. Besides, the grinding temperature and the surface roughness was declined by 7.6-25.7% and 8.6-21.8% respectively, and the residual compressive stress of tooth surface was elevated by 13.2-29.3%. It was concluded that the non-resonant theory was suitable for the designation of longitudinal vibration system for TUVAGG, and also provided a novel process technology for gear machining.