Abstract: In an infinitely variable traction roller transmission wherein two toric traction disks are rotatably supported opposite each other so as to define a toric cavity in which at least two traction rollers are disposed in engagement with the two toric disks, the toric disks have, in a plane receiving the axis of rotation of the toric traction disks, a curvature wherein their tangents at the points of contact with the traction rollers intersect on the axis of rotation of the toric disks along with the axis of rotation of the traction roller and the traction rollers are supported by support means including a guide wheel which moves along a guide track during pivoting of the support means so as to maintain engagement between the traction rollers and the toric disks in all pivot positions of the traction rollers.

Abstract: In a high ratio planetary transmission which includes in a housing coaxial input and output shafts and wherein a first sun roller structure is part of one of the shafts and disposed within the housing, a first traction ring is disposed within the housing around the first sun roller structure in spaced relationship therefrom, and a number of planetary traction rollers are supported in the space between the sun roller structure and the first traction ring, each traction roller has two sections of different diameters, one in engagement with the first traction ring and with the sun roller structure and the other being in engagement with a second traction ring which is operatively connected for rotation with the other of the input and output shafts.