Air release valve
AssigneeMulric Hydro Projects (Proprietary) Limited
InventorsKevin Richards, Michael P. Muller
Life of this patent
Estimating the term…
Abstract
The air release valve comprises a valve chamber (36) having an inlet (20) and an outlet (24). Inside the chamber is a control float (38) which is responsive to changes in liquid level in the chamber. There is also a a stack of valve members (40, 42, 44) in the chamber above the control float. The valve members have vent passages through them which increase in size with increasing height in the stack but which are smaller than the outlet (24). The top valve member (44) in the stack is designed to be lifted up, by differential air pressures acting on it, to seat on the outlet (24) and thereby reduce the effective size of the outlet when a pipeline served by the air release valve is filling with liquid and the liquid displaces air through the valve.
Claims7
An air release valve comprising:
- a valve chamber having an inlet and an outlet,
- a control float positioned adjacent the inlet in the chamber, said control float being movable, in use, in response to changes in liquid level in the chamber, and
- a stack of movable valve members positioned in the chamber above the control float, the movable valve members having vent passages therethrough which increase in size with increasing height in the stack but which are smaller than the outlet, and the top movable valve member in the stack being lifted up, by differential in air pressure acting on the top movable valve member, to seat the top movable valve member on the outlet and thereby reduce the effective size of the outlet when a pipeline served by the air release valve is filling with liquid and the liquid displaces air through the valve.
Dependencies are inferred from the claim text.