A hinged vane rotary pump including a cylindrical chamber, a rotor eccentrically mounted within the chamber, and a plurality of vanes. Each vane is hinged for pivoting movement at its approximate middle to balance hydraulic pressure across the face of the vane. The balanced pressure reduces the force applied by the vane against the chamber liner and therefore reduces wear. As one end of each vane wears against the chamber liner during operation, the axis effectively moves to the center of the vane. Preferably, stops are provided to limit movement of the vanes after maximum wear has occurred.