US Patent 7204771 Bidirectional continuous power transmission system

A bidirectional continuous power transmission system, characterized by a projecting bolt moving within a guiding opening with a rear wall and a front wall. Upon a rotating movement, the projecting bolt exerts a force on the rear wall or the front wall, depending on the orientation of the rotating movement. The force has a component parallel to an axis of rotation, causing two halves of a driven wheel to be pressed together and against a transmission belt. By providing the rear wall and the front wall of the guiding opening with defined curvatures, well-defined forces are exerted at any speed in both orientations of the rotating movement, so that torque is continuously transmitted effectively in both directions.