Abstract: A fluid pump for pumping a fluid from an input conduit to an output conduit comprising a housing having a cup-shaped rotor assembly rotatably disposed within the housing. A vane ring assembly is slidably disposed within the rotor assembly. A protuberance on the vane ring engages a corresponding indentation disposed on an inner and outer cup to prevent the vane ring assembly from rotating within the rotor assembly. A hub assembly is disposed within the vane ring assembly such that the axis of the hub assembly is parallel and eccentric to the axis of rotation of the vane ring assembly. A wear plate is in juxtaposition with the open end of the rotor assembly and a plurality of band-shaped vanes interconnect the vane ring assembly and the hub assembly. The vanes are disposed in a spaced-apart relationship parallel to the axis of rotation of the vane ring assembly to form a plurality of pump chambers.