| 摘要 |
<p>A method for increasing the operable life of corrosive liquid dispensers, and dispenser apparatus using same are disclosed. A dispenser body (l2) defines an inner cavity (20) in which a dispensing element moves. In a preferred embodiment, the moving element comprises a dual-acting piston (40) which divides the inner chamber into a motive force chamber (20a) and a retaining chamber(20b). Water pressure provides the motive force for moving the piston to dispense corrosive liquid from the retaining chamber, while simultaneously cleaning the chamber walls and piston seals (36, 37) during each diSpensing cycle. Dispensers incorporating the invention and using features such as an adjustable piston stroke and use of mechanical advantage in dispensing the corrosive liquid, are also disclosed.</p> |
