Patent ID: 8876765

Claim:
A pump module for use in a medical fluid dispensing system comprising: a pump body; first and second pump chambers, each having an interior bounded by an interior surface of the pump body and defining a predetermined interior shape of the pump chamber; first and second fluid supply passages coupled into fluid communication with the interior of the corresponding first and second pump chambers; first and second chamber outlets associated with the corresponding first and second pump chambers, each chamber outlet coupled to the interior surface and in fluid communication with the interior of the corresponding pump chamber, such that each of the first and second pump chambers acts as a fluid reservoir between the corresponding fluid supply passage and the corresponding chamber outlet; and first and second chamber inlets associated with the corresponding first and second pump chambers, each chamber inlet coupled to the interior surface and in fluid communication with the interior of the corresponding pump chamber, each of the first and second chamber inlets configured to receive a displacement member therethrough into the interior of the corresponding pump chamber such that movement of the displacement member relative to the interior surface causes fluid to move between the fluid supply passage and the chamber outlet through the pump chamber; wherein the predetermined interior shape of each of the pump chambers comprises a first portion having a generally spherical segment shape and a second portion integral with the first portion and having a generally conical shape, the first and second portions being in fluid communication with the chamber inlet and the chamber outlet; the second, generally conically shaped portion of each of the pump chambers converges to the corresponding chamber outlet.