Spline-Hobbing Machine

a metal-cutting machine tool for spline manufacture. Straight-sided and involute splines are generated on shafts with a hob. The hob rotates and simultaneously performs a feed motion, moving along the axis of the workpiece; the workpiece also rotates at a speed that depends on the number of splines being generated. In a similar manner, automatic milling machines with circular grooving cutters are used to machine slots on screwheads.