초록 ▼

A normally closed duckbill valve for controlling the direction of fluid flow in a fluid-conducting conduit and a method of manufacturing the valve are provided. The valve is formed of elastomeric material and comprises a generally cylindrical body member provided with an axial fluid passageway havin

A normally closed duckbill valve for controlling the direction of fluid flow in a fluid-conducting conduit and a method of manufacturing the valve are provided. The valve is formed of elastomeric material and comprises a generally cylindrical body member provided with an axial fluid passageway having an inlet end and an outlet end provided with an outlet slit, and progressively narrowing in cross-section from the inlet end to the outlet end to define a pair of opposed sealing lips at the outlet slit. Means for normally urging the sealing lips into a closed position are provided and comprise widened lip margins disposed at opposite ends of the outlet slit. The valve is formed by molding the elastomeric material into the preferred shape and then providing the widened lip margins with a closing bias by causing a greater amount of shrinkage in the lip margins, relative to the remaining portions of the sealing lips, during curing of the molded material from an elevated curing temperature to room temperature. One embodiment of the invention is provided with an increasing thickness of material from the generally central portion of each lip outwardly toward the outer edge of each lip margin to provide a leaf spring-like action urging the lips into a closed position.

대표청구항 ▼

A unitary duckbill valve comprising a generally cylindrical body member provided with an axial fluid passageway and having an inlet end and an outlet end, said outlet end provided with an outlet slit, said body member progressively narrowing in cross-section from said inlet end to define a pair of o

A unitary duckbill valve comprising a generally cylindrical body member provided with an axial fluid passageway and having an inlet end and an outlet end, said outlet end provided with an outlet slit, said body member progressively narrowing in cross-section from said inlet end to define a pair of opposed sealing lips at said outlet slit; a pair of enlarged lip margins disposed adjacent to the opposite ends of said outlet slit; and an increasing thickness of material progressively provided from the generally central portion of each of said lips outwardly toward the outer edges of each of said lip margins to form opposing arcuate surfaces which exhibit a leaf-spring-like characteristic tending to maintain and urge said lips into a normally closed valve position.