US Patent 11235136 Swabable valve with curvilinear valve stem

A swabable valve (10) comprising a valve stem (100) that collapses into a valve body (12), said valve body (12) including a generally cylindrical reduced diameter section (18) having a generally circular rim, said valve stem (100) having a generally cylindrical reduced diameter portion (38) that extends fully into said cylindrical reduced diameter section (18) of said valve body (12), said cylindrical reduced diameter portion (38) including a through-slit (52) that opens when said valve stem (100) collapses into said valve body (12), said valve stem (100) having a concave curvilinear surface (102) that is substantially flush with said circular rim of said cylindrical reduced diameter section (18) of said valve body (12) when said valve stem (100) is not collapsed into said valve body (12); said concave curvilinear upper surface (102) of said valve stem (100) extending rim-to-rim within said cylindrical reduced diameter section (18) of said valve body (12).