BALL PISTON PUMP

A fluid pump includes a cam plate that defines an interior cam surface having an eccentric portion and a narrow portion. A hub rotates within the interior cam surface and has a piston cavity that is in communication with an inlet port and an outlet port. A piston member is operably received within the piston cavity to define a suction phase within the eccentric portion and a pressure phase within the narrowed portion. The piston member is biased outward by rotational operation of the hub. During the suction phase, the piston member is biased away from the piston cavity to define a flow cavity that draws fluid from the inlet port. During the pressure phase, the piston member is biased by the narrowed portion into the flow cavity to push the fluid from the flow cavity toward the outlet port.