Abstract: A friction ring gear consisting of at least three driving disks which include axially movable conical disks disposed on a segment of a circle. The driving disks drive a friction ring which engages their wedge-shaped guide surfaces. There is provided a support disk on a floating axle consisting of two axially movable disk halves disposed centrally with respect to the friction ring and surrounded by the driving disks. The support disk engages all wedge-shaped guide surfaces of all driving disks, and if need be is provided with a changeable convex peripheral rim.