Meshing theory of face worm gear drive with hardened cylindrical worm

Abstract

This article proposes a novel linear contact face worm gear drive. The novel face worm gear drive consists of a face worm gear and a cylindrical worm enveloped by a tapered surface. The meshing theory for the novel face worm gear drive is systematically built up. The meshing theory on the base of the reference point is further developed aimed at the worm pair where the indexing surfaces are planar and cylindrical. The design methods of the rough size for the face worm gear are introduced. The computing method for the worm limit axial mounting distance is presented by employing the meshing limit line function. The asymmetry of the tooth surfaces for the worm pair is evaluated using the helix angle at the midpoint on the line of section for the worm gear tooth surface and the tooth profile angle for the worm axial section. Numerical results show that the geometric characteristics and the meshing properties for the tooth surface on both flanks of the novel face worm gear drive are asymmetrical. However, the meshing properties for the novel face worm gear drive are satisfactory.