Variable ratio steering gear

摘要

The tops of the teeth of a sector gear with respect to a plane of rotation of the sector gear are located on an addendum circle which is a single circular arc having a center which is located on a neutral line and which is spaced from the center of rotation of the sector gear in the direction of the arc. The portions of the top lands of the sector gear teeth at the larger diameter end of the sector gear are located on a common cylindrical surface, the remaining portions of the top lands being located on a common conical surface. The rack formed on a ball nut for engagement with the sector gear teeth is provided with a central tooth groove and outside tooth grooves, wherein the outside tooth grooves are of depth less than the central tooth groove.