Abstract: The disclosed valve has a cylindrical, central, fluid conducting core fixed within a housing by a nut located in the housing in engagement with an integral flange of said core at the latter's inner end, an oscillatory valve element having a cylindrical wall, one end sleeve portion of which extends within a cylindrical space between the housing and the core to control fluid movement through the latter, and an opposite end sleeve portion of said cylindrical wall having an extremity formation in engagement with a knob for operating the valve, and said valve element being invertible during assembling or disassembling of the valve, in which inverted condition said extremity formation coacts with said nut to effect the latter's insertion or removal in the assembling or disassembling of the valve.

Abstract: An inverted, manually operable, cylindrical, inverted-cup-shaped valve element is turnable axially back and forth between an open position in which an aperture in said element's side wall registers with a fluid passage of a fixed central core of the valve and an opening in the housing of the valve to permit fluid to flow therethrough and a closed position in which a non-apertured portion of said element's side wall registers with the valve's said fluid passage and said opening to close said passage against flow of fluid therethrough. An operating knob is provided for manually turning said valve element, and means are provided for limiting the turning of said valve element to considerably less than a full turn.