Abstract: This invention is useful in a plural component system which utilizes sequential metering of multiple fluids. In such a system for dispensing component fluids such as paint, the controller dispenses a given amount of a first fluid, and then part way through dispensing of the second fluid, calculates the amount of the second fluid required in view of the actual amount of the first fluid dispensed and then dispenses that amount. The desired tolerance maybe subtracted from the amount of second fluid dispensed so that the overrun which always takes place from the valves on the second fluid will place the mixture in the middle of the range for the dispensed fluid. During subsequent cycles, the ratio is checked in view of the actual amounts dispensed and an alarm set off if the actual ratio falls outside of tolerance.

Abstract: A system and method of operating for mixing and dispensing two liquid components, characterized in that each component is chemically stable when maintained in isolation and chemically reactive when combined with the other component. The system includes separate liquid storage containers and pumps for delivering each of the liquids through a common mixing manifold, and from there to a dispensing apparatus, the system including a further pump in one of the containers for delivering liquid through a valved, closed loop subsystem back to the container, the closed loop having therein an entry point for connection to the dispensing apparatus, and the system including a further valve for controlling the flow of the other liquid component to the dispensing apparatus, whereby the conduits leading to the dispensing apparatus may be purged of mixed liquid components, diluted, and returned to the one storage container.

Abstract: A system and method of operating for mixing and dispensing two liquid components, characterized in that each component is chemically stable when maintained in isolation and chemically reactive when combined with the other component. The system includes separate liquid storage containers and pumps for delivering each of the liquids through a common mixing manifold, and from there to a dispensing apparatus, the system including a further pump in one of the containers for delivering liquid through a valved, closed loop subsystem back to the container, the closed loop having therein an entry point for connection to the dispensing apparatus, and the system including a further valve for controlling the flow of the other liquid component to the dispensing apparatus, whereby the conduits leading to the dispensing apparatus may be purged of mixed liquid components, diluted, and returned to the one storage container.

Abstract: A system for pumping liquid materials with reciprocating pumps driven by hydraulically operated motors, wherein the pressurized hydraulic oil which is used to drive the hydraulic motors is supplied via reciprocating proportioners. The reciprocating proportioners are driven by a reciprocating air motor operated under predetermined air pressure. The system operation is characterized in that, under blocked output pressure conditions, the air motor will inherently stall and thereby limit the pressure of the hydraulic oil acting to drive the hydraulic motors, which therefore limits the pumping pressure applied to the reciprocating pumps, and limits the output pressure of the pumped liquid materials.