Vane pump (10) mechanical losses are reduced by removing vane friction
losses and replacing them with lower magnitude journal bearing fluid film
viscous drag losses. A freely rotating cam ring (70) is supported by a
journal bearing (80). A relatively low sliding velocity is imposed
between the cam ring and the vanes (26). This permits the use of less
expensive and less brittle materials in the pump by allowing the pump to
operate at much higher speeds without concern for exceeding vane tip
velocity limits.