US Patent 7578045 Method of manufacturing a trunnion

A trunnion for toroidal continuously variable transmission, includes: an oblique surface, a bottom surface, an inclining shaft having an end surface and an inclining end surface, a pivot hole, an inner flat plane, and a crossing lubrication hole. The trunnion is obtained by supporting a trunnion material taking the oblique surface or the bottom surface as a machining reference and taking one of the end surface and the inclining end surface as an axial positioning reference, and by machining the trunnion material to form the inner flat surface, the pivot hole and the crossing lubrication hole of the trunnion while keeping the trunnion material retained.