Apparatus for injecting metered quantities of fluid into a flowing stream of liquid.

摘要

A fluid injection assembly of a type designed to inject fluid into a flowing stream of liquid at a predetermined adjustable rate without the assistance of an outside power source other than the pressure of the flowing liquid itself. The assembly includes a casing (12) having the fluid (36) to be injected disposed therein and at least partially contained by a flexible membrane (26). Liquid from the flowing stream (38) is partially disposed in fluid communication with the interior of the casing so as to flow in surrounding relation to a portion of the flexible membrane whereby pressure thereon will aid in dispensing the injection fluid therefrom. An open end of the dispensing line (80) for the injection fluid is disposed within the flowing stream (38) so as to create a negative pressure further adding in removal of the fluid from within the casing. A liquid flow rate meter (48) is provided so as to give a constant visual indication of the rate of flow of the liquid into which it is desired to inject the fluid. A similarly constructed fluid injection meter (88, 90, 92, 94) is provided so as to permit visual observation of the rate of fluid injection. A dispensing valve (86) is provided to allow regulation of the rate of injection of fluid into the flowing stream of liquid.