Abstract: A fluid dispensing apparatus having a) a compressed gas or CO2 cartridge controller, b) a hydraulic pressure medium connected to the CO2 cartridge controller, c) a flow control valve connected to the hydraulic pressure medium; and d) a hydraulic piston connected to the hydraulic pressure medium, whereby a CO2 cartridge applies pressure to the hydraulic pressure medium controlled by the CO2 cartridge controller, the flow control valve is operated to precisely meter hydraulic fluid to the hydraulic piston, and the hydraulic piston provides the linear force to dispense a fluid product with similar and matching regulation under pressure. A rotary valve can be provided to use spent CO2 to retract the piston.

Abstract: A dispenser for mixing fluid materials and dispensing the mixture includes a common passage having an output or dispensing nozzle end and an input end into which the separate fluid materials are injected from separate passages, the common passage being essentially straight and of constant cross section shape and size from end to end, a clean out plunger projecting into the input end of the common passage closing that end when the plunger is at its withdrawn position, a drive for the plunger for driving it through the common passage from the input end to the output end, forcing any material in the common passage out of the dispensing nozzle, so that the common passage is cleaned out and drive for withdrawing the plunger through the common passage back to its withdrawn position so that the materials can again be injected into the common passage and dispensed from the nozzle.