Method for inserting an additive liquid into a flowing fluid and

Abstract

A dispensing assembly for discharging a flowing fluid into which a desired amount of an additive liquid has been inserted includes a container for the additive liquid which may be removed from a dispenser body. The container is normally positively biased to a closed condition to prevent escape of the additive liquid. Opening of the container is effected upon establishment of a predetermined minimum pressure by the flowing fluid in the dispenser body. Additive liquid is forced from the container into the flowing fluid by a metered amount of flowing fluid inserted into the container to cause a flexible pressure member to force the additive liquid from the container. Opening of the container is not achieved until after the pressure member is exerting a force on the additive liquid. Resistance to flow of the additive liquid from the container is minimized, so that the amount of additive liquid inserted into the flowing fluid is dependent upon the flow rate of the flowing fluid and is essentially independent of the characteristics of the additive liquid. An alternative rinse path is provided to insure rinsing of the dispenser body before and after opening of the container. An appropriate flow regulating arrangement is utilized to selectively direct the flowing fluid through the alternative rinse path or to a pressure chamber to activate a mechanism for opening of the container.