Gear Profile with Synthetic Curves: A Comparison Study

The most common mode of failure of a gear is due to generation of maximum bending stress caused at the root. This bending stress can be decreased in the gear, for the same bending moment, by increasing the section modulus at the root. The aim of this work is to study various designs of gear tooth profiles including involute profile such that the maximum bending stress at root can be decreased without changing the module or pressure angle of an existing gear. This paper represents a methodology to design various gear profiles with synthetic curves, i.e., Bezier curve, NURBS, and B-spline curve. Thereafter a comparison study between the gear tooth profiles using involute profile and synthetic curve profiles is carried out using analytical techniques. The result shows that the gear tooth profile using NURBS gives higher section modulus than involute profile.