US Patent 7497848 Needleless medical connector with expandable valve mechanism

A needleless connector for medical use, adapted to facilitate the flow of fluid therethrough, includes a housing having an inlet port and an outlet port. The connector also includes a flex-tube assembly defining a fluid path between the inlet port and the outlet port. The flex-tube assembly is movable between uncompressed and compressed states. The flex-tube assembly has a first internal volume when in the uncompressed state and a second internal volume, greater than or substantially equal to the first internal volume, when in the compressed state.