To address the stability issues in face gear transmission and to achieve more balanced contact and load distribution, this study investigates the tooth surface geometry and meshing characteristics of non-orthogonal offset face gears. First, coordinate systems for the gear pairs are established, and the tool equation, meshing equation, and tooth surface equation are derived. Then, the effects of parameters such as pressure angle and module on the theoretical inner radius, outer radius, and face width are analyzed. Based on this, a tooth surface modification method is proposed, and the modification parameters are optimized. Furthermore, the influences of shaft angle and offset distance on the amplitude of transmission error and the maximum contact stress are examined, followed by an evaluation of edge contact behavior after modification. The results show that proper modification significantly improves edge contact performance. Within certain ranges of modification amounts and load conditions, the modified gears effectively reduce the transmission error amplitude and maximum contact stress, thereby enhancing the stability and reliability of gear transmission.
Chu et al. (2026) studied this question.