Abstract: This invention relates to a valve having a valve member in the form of a roller supported by a roller support such that the roller when moved to closed position is forced against a valve seat and such that inlet pressure in said valve aids in maintaining said roller in a tight closed position, said valve preferably comprising a tubular valve housing having an axial inlet and a peripheral outlet.

Abstract: Gate valve having a closure member mounted on a swinging arm pivotally mounted for movement transversely of the axis of the valve openings. A wedge member carried by the arm drives the closure member in a direction parallel to the axis of the openings when moved longitudinally of the arm. An actuator pivots a cam which bears against the wedge member to swing the arm to a predetermined position in which the closure member is aligned with the openings and thereafter to move the cam to drive the closure member axially and seal one of the openings. Resilient members urge the closure member toward its retracted position and prevent the wedge member from moving forward until the arm reaches the predetermined position.