US Patent 7451763 Pneumatic shuttle valve for a ventilator system

A pneumatic shuttle valve for a ventilator is disclosed. The pneumatic shuttle valve selectively connects one of two inlet openings to an outlet opening. The shuttle valve has a plug that is forced by gas pressure entering the second inlet opening, to move to and seal against a first sealing surface, thereby forming a passageway between the second inlet opening and the outlet opening. The plug is forced by gas entering the first inlet opening, to move to and seal against a second sealing surface, thereby forming a passageway between the first inlet opening and the outlet opening.