On the Study of the Active Tooth Surfaces’ Geometry of the Spatial Rack Drives

In this study, a spatial rack system, that transforms a rotation motion into rectilinear translation by means of a cylindrical worm and a helical rack is considered. This type of motions’ transformation is realized by the conjugated active flanks of the worm and the gear rack. This paper deals with the theoretical approach to their synthesis. It is based on the second principle of T. Olivier. The obtained equations of the surfaces of the spatial rack drive are of importance when the algorithms for the synthesis of this type of mechanism are elaborated.