Ball piston pump

A fluid pump comprising:

• a cam plate having an interior cam surface that defines alternating eccentric and narrowed sections;
• an end assembly that includes an inlet channel and an outlet channel;
• a hub that rotates within the interior cam surface and having piston cavities in communication with an inlet port and an outlet port and in communication with the inlet channel and the outlet channel;
• and
• piston members that are respectively positioned within the piston cavities to define flow cavities therebetween, wherein rotation of the hub generates a centrifugal force that biases the piston members toward the interior cam surface and away from a rotational axis of the hub, the interior cam surface including a generally elliptical profile having two eccentric sections and two narrowed sections, wherein:
• the alternating eccentric and narrowed sections define a suction phase and a pressure phase, respectively, of each piston member;
• each suction phase biases the piston members outward to expand the flow cavity, the suction phases drawing a fluid into the flow cavity from the inlet port;
• each pressure phase biases the piston members into the respective piston cavities to compress the flow cavity and expel the fluid from the flow cavity and toward the outlet port;
• the inlet port is aligned with the eccentric sections and the outlet port is aligned with the narrowed sections;
• and
• a pressure relief channel extends between the two eccentric sections and serves to equalize a suction of the suction phase between the two eccentric sections.

A fluid pump comprising:

• an end assembly having a fluid inlet and a fluid outlet, wherein a fluid path extends between the fluid inlet and the fluid outlet, the fluid path having centrifugal sections and centripetal sections that move fluid through the fluid path;
• a cam plate having an interior cam surface that defines the centrifugal sections and the centripetal sections;
• and
• a hub assembly that rotates about a rotational axis, the hub assembly comprising a plurality of piston members and a central hub, wherein,
• rotation of the hub assembly through the centrifugal sections and the centripetal sections defines a radial movement of each piston member of the plurality of piston members;
• the plurality of piston members operating in a radially outward direction in the centrifugal sections to expand corresponding flow cavities that draw the fluid from an inlet port;
• the plurality of piston members operating in a radially inward direction in the centripetal sections to compress the corresponding flow cavities and push the fluid out of the corresponding flow cavities and toward an outlet port;
• and
• the end assembly includes a pressure relief channel that extends between the centrifugal sections and equalizes a suction within the corresponding flow cavities to draw the fluid from the inlet port.