Patent ID: 7849871

Claim:
A system for pumping fluids, comprising: a pressurized fluid supply source; a fluid reservoir; a discharge manifold; a pump disposed between, and in fluid communication with, the fluid reservoir and the discharge manifold, the pump adapted to receive fluid at a pressure; and a control system for maintaining the pressure of the fluid received by the pump at a substantially constant value, the control system comprising: a fluid level gauge, in fluid communication with the fluid reservoir, the fluid level gauge having a multiplicity of set points; a signaling element operably coupled to the fluid level gauge, the signaling element: receiving signals from the set points, determining rates of change of the fluid level in the fluid reservoir, and delivering controlling signals in response to the determined rates of change; and a control valve, in fluid communication with the fluid reservoir and the pressurized fluid supply source, and operably coupled to the signaling element, the control valve responding to the controlling signals from the signaling element to maintain the level of the fluid in the fluid reservoir at a substantially constant level, so that the pressure of the fluid received by the pump is maintained at the substantially constant value.