Effects of helix deviations on the vibration of cylindrical gear pairs

A transverse-rotational-axial coupled dynamic model for cylindrical gear pairs was built, considering the excitations of time-varying mesh stiffness, gear error and meshing impact. And the effects of helix deviation on the vibration of spur and helical gear pairs were investigated. The results show that the helix deviation has little effects on the vibration of spur gears but has remarkable influences on the vibration of helical gears. The concave helix always brings the largest vibration, and the negative helix angle errors induce smaller dynamic loads than the concave helix. Under most load conditions, the positive helix angle errors bring a smaller vibration than the ideal helix does and the convex helix gives the smallest vibration among all. Therefore, the helix deviation can be neglected when studying the dynamic responses of spur gears but should be taken into account when studying the dynamic responses of helical gears.