摘要 |
A magnetic safety valve for installation through a tank wall incorporates a piston movable within a valve body. The valve is held normally-closed by two opposite-pole magnets, one in the inner end of the piston, and one in the valve body. A vacuum produced by a pump connected to the valve will act upon the outer end of the piston, producing a force tending to move the piston outward. When the vacuum-induced outward force on the piston exceeds the attractive force between the two magnets, it pulls the piston outward and away from the valve body magnet, unseating the inner end of the piston from the valve body, and allowing outward fluid flow through the valve. A second valve seat may be provided for engagement with an outer portion of the piston to prevent uncontrolled fluid flow out of the tank in the event of valve damage. |