(under subclass 413) Apparatus in which the source of fluid pressure is the tank holding the liquid accumulation to the level of which the float responds.
(1) Note. Many of the patents in this subclass utilize the steam pressure in a boiler for operating a valve controlling the flow of water into the boiler.
SEE OR SEARCH THIS CLASS, SUBCLASS:
156+, for gas pressure discharge of liquid feed traps to a boiler.
192+, and 202, for float controlled discriminating outlets for liquid and gas in diverse fluid containing pressure systems.
SEE OR SEARCH CLASS 251, Valves and Valve Actuation,
33+, for valves actuated by fluid servo-motors deriving working fluid from the line controlled by the valve.
