Fire protection shut-off device includes additional layer of heat-expanding material to close gap which exists after closure member has reached its closing position

摘要

The shut-off device has a housing and a closure flap (4, 6) held in the open position by a locking unit which is released when heated. The closure flap contains in an edge area (14, 16) facing the housing or further closure member in the closed position, an additional layer (22) of material which expands when heated so that a gap (26) which exists after the closure member has reached its closing position can be closed. The additional layer can be mounted on the outside of a web (10) provided in the edge of the closure flap.