Dynamic Characteristics of a Transmission System Based on Tooth Surface Modification of Double-Pressure-Angle Helical Face Gears

To investigate the dynamic characteristics of a double-pressure-angle helical face gear transmission system, a digital tooth surface of a double-pressure-angle helical face gear, considering tooth surface modification, was established based on the generation principle of a disk grinding wheel. The time-varying mesh stiffness (TVMS) of the gear pair was calculated using the loaded tooth contact analysis (LTCA) method. A dynamic model of the double-pressure-angle helical face gear transmission system was then developed using the lumped-mass method, and the corresponding dynamic equations were derived. The dynamic characteristics of the system, as well as the effects of input speed, drive-side pressure angle, and tooth surface modification, were analyzed. The results show that increasing the drive-side pressure angle reduces the peak displacement vibration along the line of action, with a reduction of 31% at 32° compared with 24°. The input speed has a significant effect on the system dynamic response; as the speed increases, the vibration response first increases and then decreases, reaching its maximum at 9600 rpm. Bidirectional tooth surface modification on the drive side of the helical face gear changes the geometric contact pattern of the gear pair from localized concentration to a more uniform distribution. Meanwhile, the scatter points on the Poincaré section change from dispersed to concentrated, and the main acceleration peak along the line of action is reduced by 45.8%. These results provide theoretical support for the dynamic design of helical face gear transmission systems.