Patent attributes
A substrate container includes a container portion having an open side or bottom, and a door to sealingly close the open side or bottom, one of the door and the container portion defining access structure. The substrate container additionally includes a check-valve assembly, the check-valve assembly being retained with respect to the access structure to provide fluid communication with an interior of the substrate container. The check-valve assembly includes a grommet, the grommet being formed of an elastomeric material. A valve seat is disposed within the grommet, the valve seat being integrally formed with the grommet according to one aspect, and being formed of a separate piece according to another aspect. An elastomeric valve member, specifically an elastomeric umbrella valve member according to one aspect, is disposed within the grommet and held to engage the valve seat, thereby restricting fluid flow through the check-valve assembly with respect to the interior of the substrate container.
