US Patent 7264567 Wedge loading mechanism for traction drives

A wedge loading mechanism for an eccentric planetary traction drive in which a roller having a flexibly mounted shaft is positioned between two raceways forming a convergent wedge. Rotation of either of the two raceways wedges the roller within the convergent wedge squeezing the roller between the two raceways thereby transmitting rotational motion and torque between the two raceways. The flexibly mounted shaft generates differences between an effective supporting stiffness of the roller and an contact effective stiffness at the points where the roller contacts the two raceways. The difference in the effective stiffness allow the roller to operate efficiently at smaller convergent wedge angles.