Fire barrier in ventilation pipes

摘要

The fire barrier comprises a rotary movable valve plate (6) inserted in a frame enclosing a free flow section. Surfaces which are defined by gaps (8,9,10) between facing edges on the valve plate (6) and frame side parts (2,3,4) and which cling together in the closed position of the valve plate run at an angle alpha > 0 deg. to the plane of the valve plate. Recesses (13) are formed in the axial area where the axis (7) passes through the clinging faces. Each recess can be sealed by inserted sealing discs. Axle bearings are installed in the recesses. The frame and valve plate can be made of the same material. The surfaces defined by the gaps have elastic sealing lips.