Rubber-geared pump with shaftless gear

摘要

A gear pump is described for pumping extremely low volumes of fluid at extremely low rates of flow. The pump includes a housing with a cavity therein and a pair of gears rotatable within said cavity. One of the gears is shafted and the other is shaftless, and the gears are made of resilient material with the diameter of the periphery of the tips of the gear teeth exceeding the diameter of the cavity in which they rotate. The face width of the gears also exceeds the depth of the cavity in which they rotate.