(under subclass 81) Devices of the type in which the operating means is responsive to the flow of a fluid (including air-currents, wind, etc.), as distinguished from those which are responsive merely to the static pressure of the fluid.
(1) Note. See alphabetical index to the classification of patents, the title "Flow" for the distribution of flow controlled devices in the several classes.
SEE OR SEARCH CLASS
137, Fluid Handling, particularly
98+, 107, 459+, 486+, 496, and 497+ for valves with flow responsive actuating means.