Overflow valve system

An overflow valve system for preventing the filling of a liquid container through a supply tube above a predetermined level, said system comprising:

• a housing defining an enclosed housing cavity having a top housing end and a bottom housing end;
• a bracket attached to a surface of said housing for mounting said housing in communication with said liquid container at approximately the level at which flow of liquid being supplied to said contaier via said supply tube is to be interrupted;
• a pipe fitting attached to the wall of said housing, said pipe fitting having at a first pipe-fitting end an injection nozzle located in said housing cavity near the bottom housing end for injecting liquid axially upwardly in said housing cavity, said nozzle having a thread means for providing female threads for meshing with male threads of a shank of a water-closet ballcock and thereby providing a sealed attachment therebetween so that liquid flowing from said nozzle flows through a bore of said ballcock shank, said female threads meeting national standards for threadably engaging male threads on national-standard ballcock-shanks, said pipe fitting having at a second pipe-fitting end an attachment means for attaching said pipe fitting to said supply tube for furnishing liquid to said nozzle;
• whereby, a standard water closet ballcock can be mounted in or removed from said overflow valve system by screwing it onto or off said nozzle from within said housing without removing elements of said bracket and said housing, said ballcock, when mounted on said nozzle, controlling the flow of water through said pipe fitting into said housing cavity to not exceed said predetermined level.