US Patent 9725225 Micro-volume dispense pump systems and methods

Provided is a fluid dispense pump comprising a pump housing and a cartridge body positioned along an axis. The cartridge body comprises a chamber and a feed aperture extending through a surface of the cartridge body to the chamber. A fluid shaft extends through the cartridge body along the axis. The fluid shaft has an inlet port positioned in the chamber of the cartridge body. One of the cartridge body and the fluid shaft is attached to the pump housing and is fixed relative to the pump housing. The other of the cartridge body and the fluid shaft moves relative to the one of the cartridge body and the fluid shaft to change a position of the inlet port relative to the feed aperture during a dispensing operation.