Patent Number: 6,253,983

Title: Vacuum conveyor

Abstract: Apparatus and process for guiding a running web. The apparatus includes at least two guide rolls, which includes at least one driven roll, a suction box coupled to a vacuum source and having a wall with an aperture, an air-permeable belt tensioned over the at least two rolls, and the suction box being positioned within a loop formed by the belt. The suction box is positioned to suction a portion of the belt that is adapted to guide the running web. The apparatus also includes a vacuum control adapted to control a degree of vacuum in the suction box that includes a movable element positioned adjacent the aperture and an inner surface of the wall. The moving element is adapted to open and close the aperture, and an actuator is coupled to the movable element to effect the opening or closing of the aperture. The process includes applying a vacuum pressure to the suction box to decrease an internal pressure with the suction box, applying an actuator force on the movable element in a direction toward an aperture in the apertured wall, so that the movable element is located in a position to close the aperture. The process also includes guiding a transport belt over the suction box, transporting at least a portion of the material web on the transport belt, so that the suction box suctions at least a portion of the material web onto the transport belt, releasing the movable element from the aperture, so that the aperture is opened and the suction on the at least a portion of the material web is reduced, and closing the aperture with the movable element, so that the suctioning of the at least a portion of the material web onto the transport belt is increased.

Inventors: Dadd; James (North Delta British Columbia, CA)

Assignee: Voith Sulzer Papiertechnik Patent GmbH

International Classification: B65H 20/10 (20060101); D21G 9/00 (20060101); B65H 020/00 (); D21F 003/10 ()

Expiration Date: 07/03/2018