Patent attributes
Isolation valves of the invention are advantageously mechanically actuated. Such valves and associated methods comprise a first port in fluid communication with a first component; a second port in fluid communication with a second component; a third port in fluid communication with a third component; a diaphragm disposed within the valve for closing a normally open internal pathway to occlude fluid communication between the first port and the second port in response to a pressure differential across the diaphragm; and a flow sensitive pressure device for controlling the pressure differential across the diaphragm. Fluid flows from the second component to the third component upon closing of the normally open internal pathway. In an exemplary embodiment, isolation valves and methods of the invention are adapted for use in fuel tank emission control systems.
