Patent ID: 6027613
Filing Date: 2000-02-22
Classification: D21F

Abstract:
A suction device for use in a machine for producing a sheet comprising:a contact surface coupled to a web section, the web running in a run direction;a suction box applying vacuum pressure to suction the web section, the vacuum pressure creating a normal force between the web section and the contact surface;a release mechanism releasing the suction box from the web section during the application of the vacuum pressure to reduce friction between the web section and the contact surface;a control device to operate the release mechanism to movably position the suction device and the web section and operating the release mechanism in response to an operating parameter of the machine, the operating parameter comprising a parameter selected from at least one of web tension, type of felt used, felt run time, length of the suction device and the differential pressure on the suction device; andthe release mechanism designed to be an adjustment mechanism elevating the suction device to an elevated position above the web section by a distance reducing the friction between the contact surface and the web section without the web section detaching from the contact surface; the control device operating the adjustment mechanism while vacuum pressure is created in the suction device.