Check valve structure for use in drains

A check valve structure which comprises:

• an annular elastomeric member having upper and lower ends, said member in an uncompressed condition having a cylindrical peripheral wall and a plurality of sealing rings extending from said wall and extending completely around said member, said sealing rings being spaced from one another, said member in an uncompressed condition being capable of fitting within the interior of a drain so as to extend across the interior of a drain with said sealing rings engaging the interior of the drain so as to hold said structure in place,
• a rigid upper annular end plate located against the upper end of said elastomeric member,
• a rigid lower annular end plate located against the lower end of said elastomeric member,
• fasteners extending between said end plates for moving said end plates toward one another in order to apply compression to said elastomeric member in order to cause expansion of the exterior of said elastomeric member into sealing engagement with the interior of the drain, said fasteners being spaced around the interior of said member,
• valve seat means for use in closing off the interior of said lower end plate located on said lower end plate,
• support means located on said upper end plate for use in supporting a valve member, said support means including guide means for controlling the movement of a stem, and
• an upwardly directed conical, elastomeric buoyant valve member having a hollow interior and an open bottom extending across the lower end of said valve member, said valve member being capable of seating against said valve seat means movably mounted on said support means so as to be capable of being moved from a normally open position spaced from said valve seat means to a closed position in contact with said valve seat means, said valve member including a stem extending therefrom through said guide means,
• said stem having an enlarged head normally engaging said support means so as to hold said valve member with respect to said support means and said valve seat.