Based on the form grinding method geometry theory and gear profile grinding machine kinematics principles gears

a segment topographic modification method of helical gear drives was proposed. Profile segment modification was achieved by changing length of involute occurrence line of invloute profile on the top and root of the tooth; longitudinal segment modification was achieved by attaching to a parabolic and linear radial feed motion when forming grinder is moving. The formula of topographic modification tooth flank was derived based on form grinding process

and the boundary of topographic modification tooth flank was divided and calculated to establish the equations of motion for every servo axis of form grinding machine. According to numerical simulation results of the tooth flank

machining on the five-axis computer numerical control (CNC) gear form grinding machine and on-machine topographic measurement can verify the feasibility of topological modification of tooth flank by the grinding method. Combined the given conditions of rotating speed and operating load gearbox loading experiment

the vibration energy level amplitude of gearbox is dropped 0.008dB and noise is reduced by about 2dB. The research results show that segment topographic modification is effective in reducing gear drives vibration and noise.