Patent ID: 8251853

Claim:
A friction gear for transmitting torque, comprising: three rotating construction units including a sun wheel shaft, one or more planetary rolling bodies, and an outer hollow body; at least one of said three rotating construction units being elastically deformable; said rotating construction units being disposed to define respective pairs of friction contact surfaces rolling against one another under a pressure force with punctiform contact or linear contact, said friction contact surfaces of pairs of at least two said rotating construction units that roll against one another having a transverse curvature perpendicular to a circumferential curvature thereof, with an extent of said transverse curvature of at least one of said construction units being defined by a design contour thereof and also by an elastic component deformation upon assembly of the friction gear and being dimensioned to generate linear contact; wherein a straight and/or a transversely curved contact line of at least one pair of friction contact surfaces rolling against one another has a spatial line alignment with respect to an axis of said sun wheel shaft to generate a drilling/rolling ratio of 0.001 to 0.2; and wherein pressure forces between the individual said friction contact surface pairs, with conventional utilization of the mechanical rolling strength of the construction units and a friction value μ of the friction contact surface pairs, result in substantially equal values for a maximally transmissible torque both between said sun wheel shaft and a sum of said planetary rolling bodies and also between the sum of said planetary rolling bodies and said outer hollow body.