US Patent 8413954 Control valve

There is disclosed a control valve suitable for particulate flow and/or for a liquid stream, comprising a spherical surface with cut-off top and bottom areas, a cylindrical extension depending from the cut-off top area of said spherical surface, a collar further extending from the cylindrical extension, a common internal diameter passage through said spherical surface, cylindrical extension and collar, and said valve further comprising opposing arcuate lids, having an interior spherical concave surface, hinged to the spherical surface to provide a close tolerance relationship with the spherical surface, and an overlapping band on one of the lids to create an arcuate, spherical, concave, recessed area for reception of the leading surface of the other lid, which lids open and close at fast rates by outside means to provide an intermittent seal to the flow of the particulate or of the liquid during the operation of the control valve.