scope:

This paper shows a detailed knowledge of how to design the tooth-surface-modification to realize a quiet helical gear pair where face width is finite in length.

The performance of gears with bias-in and bias-out modification are discussed considering the effect of the shaft parallelism deviation.

To clarify the effect of the tooth deviation types on the vibration behavior of helical gear pairs, performance diagrams on vibration are introduced and created, in which the acceleration level of gear pairs are shown by contour lines on the contact ratio domain.