Concealed keyhole cover plate for fire doors - has eccentric hinge pin ensuring gravity actuated covering of keyhole

摘要

The concealed key hole covering plate has an external actuator projecting through the lock fitting. The key hole covering plate swings back into its specified covering position automatically. This arrangement can be used in fire protection doors and the keyhole cover plate is also protected against fire even if the steel plate covering plastics has been melted or burnt away. The keyhole cover plate (3) is pivoted eccentrically relative to the axis through its centre of gravity by a pin (6) above the keyhole (5). The keyhole cover plate is held against a stop (7) by gravity. The keyhole cover plate has an external-actuating, serrated handle projecting radially outward from the pin (6).