초록 ▼

A breathing apparatus comprises a supply of breathable gas and a facepiece by which breathable gas is supplied to a wearer, the facepiece including a supply valve for delivering gas to the interior of the facepiece, and an exhaust opening closeable by an exhaust valve for allowing the egress of exha

A breathing apparatus comprises a supply of breathable gas and a facepiece by which breathable gas is supplied to a wearer, the facepiece including a supply valve for delivering gas to the interior of the facepiece, and an exhaust opening closeable by an exhaust valve for allowing the egress of exhaled gas from the facepiece. The exhaust valve comprises a movable valve member which, in a first position, closes the exhaust opening in the facepiece, in a second position is displaced toward the interior of the facepiece relative to the first position while still in sealing engagement with the exhaust opening to open the supply of breathable gas, and in a third position is displaced outwardly of the facepiece relative to the first position to open the exhaust opening to allow the egress of exhaled gas. The valve member is biased towards the second position by a single significant biasing means. A sealing element is preferably interposed between the valve member and the exhaust opening.

대표청구항 ▼

[ I claim:] [1.] In a facepiece for a breathing apparatus by which breathable gas is supplied to a wearer and exhaled gas is exhausted therefrom, said facepiece including a supply valve for delivering breathable gas to the interior of said facepiece and an exhaust opening closeable by an exhaust val

[ I claim:] [1.] In a facepiece for a breathing apparatus by which breathable gas is supplied to a wearer and exhaled gas is exhausted therefrom, said facepiece including a supply valve for delivering breathable gas to the interior of said facepiece and an exhaust opening closeable by an exhaust valve for allowing the egress of exhaled gas from said facepiece, the improvement wherein said exhaust valve comprises an inwardly biased valve member movable relative to said exhaust opening and having a first position in which said valve member closes said exhaust opening and is in sealing engagement therewith, a second position in which said valve member is displaced towards the interior of said facepiece relative to said first position with said valve member still in sealing engagement with said exhaust opening, a third position in which said valve member is displaced outwardly of said facepiece relative to said first position and wherein said exhaust opening is open for allowing egress of exhaled gas, a single biasing means for biasing said vale member towards said second position, and operating means engageable by said valve member when said valve member is in said second position for opening said supply valve.