US Patent 7326301 Application device

A device for direct or indirect application of liquid or viscous coating medium by way of an application system onto a material web, especially a paper or cardboard web, including a weakening device for weakening the boundary layer of air that is carried along by the application surface. The weakening device is located prior to the applicator device viewed in direction of travel of the application surface. The weakening device includes a blowing device and a suction device. The blowing device is located prior to the applicator device when viewed in direction of travel of the application surface and produces an air flow in opposite direction to the direction of travel. The suction device is located prior to the blowing device when viewed in direction of travel of the application surface and sucks off at least a portion of the air flow that is produced by the blowing device, as well as at least a portion of the boundary layer of air that is carried along by the application surface.