Patent attributes
Embodiments of the present invention are related to a pumping system that accurately dispenses fluid using a multiple stage (“multi-stage”) pump. More particularly, embodiments of the present invention provide for control of a feed stage pump to regulate fluid pressure at a downstream dispense stage pump. According to one embodiment of the present invention, a pressure sensor at the dispense stage pump determines the pressure in a dispense chamber. When the pressure reaches a predefined threshold, the dispense stage pump can begin to increase the available volume of the dispense chamber, thereby causing the pressure in the dispense chamber to drop. As the pressure decreases/increases at the downstream pump, the pressure applied by the upstream pump can bed increased/decreased.
