Design, simulation of meshing, and contact stresses for an improved worm gear drive

A version of a worm gear drive with improved bearing contact, reduced level of transmission errors and lessened sensitivity to errors of alignment is proposed. Unlike the existing approach, the hob and worm tooth surfaces are mismatched (in addition to the oversize of the hob). A localized bearing contact in longitudinal direction, with a negative (but not positive) function of transmission errors is provided in favor of increasing contact ratio. The positive features of proposed design have been confirmed by TCA (Tooth Contact Analysis) applied for unloaded and loaded gear drives.