Abstract: An engine has a pair of rotors, both housed within the same housing. The housing has an interior cavity which is preferably spherical but need only be partially spherical, the remainder at least having rotational symmetry. Each rotor is mounted on an axis that passes through the center of the cavity, the respective axes of the rotors being at an angle to each other, with the center of each rotor being at the center of the cavity. The rotors interlock with each other to define chambers. Vanes or pistons defined by a contact face and a side face protrude from the rotors. The side faces and contact faces, and the housing interior define chambers that open and close as the rotors rotate. Each contact face of one rotor is defined by the rotation of a conical section of material on the other rotor, so that there is constant linear contact between opposing vanes on the two rotors, at least on one side of the engine. The rotors may face each other or be one inside the other.
Abstract: A rear suspension system for a bicycle. The system directs the rear wheel along a predetermined, S-shaped path as the suspension is compressed. The path is configured to provide a chainstay lengthening effect only at those points where this is needed to counterbalance the pedal inputs of the rider; at those points in the wheel travel path where there is a chainstay lengthening effect, the chain tension which results from the pedal inputs exerts a downward force on the rear wheel, preventing unwanted compression of the suspension. The system employs a dual eccentric crank mechanism mounted adjacent the bottom bracket shell to provide the desired control characteristics.