Patent ID: 8210189

Claim:
A bi-solvent cleaning system for removing contaminants from precision components comprising: a cleaning portion having a cleaning tank including a first solvent having a first solvent boiling point, wherein a precision component is dipped into the cleaning tank and is removed with residual amounts of the first solvent; a rinsing portion having a rinse tank including a second solvent, the second solvent selected to have a second solvent boiling point, wherein the first solvent boiling point is higher than the second solvent boiling point, the second solvent dissolving the residual amounts of the first solvent remaining on the precision component as the precision component is dipped into the rinse tank to form a solvent mixture of the first solvent and the second solvent, the rinse tank further including a condensing coil above the second solvent; a solvent recovery portion having a recovery tank for holding a solvent mixture of the first solvent and the second solvent, the recovery tank separated from the rinse tank by an overflow weir, the recovery tank further including a heat source, a recovery loop fluidly interconnecting the rinse tank and the recovery tank, the recovery loop including a recirculation pump, a cooling source, a recirculation filter and a plurality of valves, and a controller configured to control the recovery loop in a cleaning mode of operation and actuating the recirculation pump and valves to direct solvent mixture through the recirculation filter and configured to control the recovery loop in a recovery mode of operation and actuating the recirculation pump and valves to direct solvent mixture through the cooling source, wherein the heat source and pump energy imparted from the recirculation creates a shared second solvent vapor blanket above the rinse tank and the recovery tank during the cleaning mode of operation such that a pure distillate of the second solvent condenses on the condensing coil and flows into the rinse tank such that the level of the second solvent rises until it cascades over the overflow weir and into the recovery tank, wherein the concentration of the first solvent in the recovery tank increases over time causing a solvent mixture boiling point to continually increase until the solvent mixture boiling point exceeds the second solvent boiling point by at least about 10° C., and wherein the recirculation pump recirculates the solvent mixture in the recovery tank through the cooling source during the recovery mode of operation such that said solvent mixture separates to form a first solvent portion and a second solvent portion that is each visually distinguishable to an unassisted eye for easier removal of the first solvent portion from the recovery tank.