Patent ID: 8156919

Claim:
A rotary vane engine, comprising: a housing; a rotor mounted within the housing and rotatable in relation to the housing about an axis of rotation, the rotor comprising a shaft and plurality of vanes mounted on the shaft, the vanes and the housing defining a plurality of chambers each having a volume that receives a pressurized gas for expansion within the chamber to impart rotation to the rotor, wherein: an inlet and an outlet are formed in the housing; the inlet receives the pressurized gas and directs the pressurized gas to the chambers before the pressurized gas has been expanded; the pressurized gas is exhausted from the chambers by way of the outlet after the pressurized gas has been expanded; one or more vent openings are formed in the housing at circumferential positions located between the outlet and the inlet in the direction of rotation of the rotor; and one or more ports are formed in the housing at circumferential positions located between the inlet and the outlet in the direction of rotation of the rotor; at least one of: a hydraulic actuator; a screw jack; a pneumatic cylinder; a cam; a ramp; and a lobe coupled to the rotor for moving the rotor in a direction substantially perpendicular to the axis of rotation so that a volume of each of the chambers at a given angular position of the chamber in relation to the housing is variable and an expansion ratio of the pressurized gas is variable; a manifold in fluid communication with the one or more vent openings and the one or more ports; and a controller that causes the manifold to direct the pressurized gas from the one or more vent openings to the one or more ports.