Alarm system prior to firedoor drop

#This invention is directed to a warning system for a firedoor actuated into a closed-position mode, and in particular, a system for warning persons in the physical proximity of a fire door that the latter will be closing within a short period of time, such as, for example, within 10 to 30 seconds.

#Firedoors across doorways are closed automatically upon detection of smoke. The existing system to do this in practice in a typical installation includes a smoke detector, a time-delay release mechanism, a firedoor-and-hood assembly, and an applicable electrical circuit between smoke detector and mechanism. Very little time elapses between actuation of such existing system and the closing of the firedoor, whether the latter falls or drops in a vertical manner or is operated from the side of a doorway. Such existing system does not consider the danger always present, viz., that persons in physical proximity to the doorway will be struck by the fire door in its closing, and thereby be injured.

#This invention provides warning, visual and audible, to a person who is in the vicinity of a firedoor, that it will be closing in a matter of so many seconds. Such person or persons then can move swiftly away, out of danger of injury by the closing of the firedoor upon their persons.

#FIG. 1 is a perspective view of an installation of the invention in a firedoor environment.

#FIG. 2 is a frontal view taken on line 2--2 of FIG. 1, of a wall panel including audible and visual warning elements of and test means for the invention.

#FIG. 3 is a generally cross-sectional view of an installation of the invention in relation to a wall environment including a firedoor and its release mechanism, taken on line 3--3 of FIG. 1.

#Referring now to the drawing wherein reference characters therein correspond to like numerals hereinafter following, reference character 10, FIG. 1, refers to an assembled installation of the invention at a firedoor location 11. A typical state-of-the-art firedoor location 11 includes a doorway 12 formed in a wall 13, vertically disposed sides 14 joined by a lintel (not referenced) to form the doorway 12 mounted upon a floor 15. The construction of these building elements is in accordance with generally present acceptable practices. To the one side of wall 13 along which a firedoor 16 is disposed, a hood 17 is conveniently mounted above the doorway, in suitable and known manner, to house firedoor 16. A leading edge or foot-piece 18 of firedoor 16 is disposed in a hanging fashion in the door's non-actuated position mode.

#Firedoor 16 is assembled in its hood 17 in accordance with generally known acceptable practices, and is not part of the instant invention, except to the extent that an element 20, FIG. 3, of the firedoor-and-hood assembly is operatively connected to the system of the present invention via a time-delay release mechanism 21 utilized in existing automatic firedoor assemblies.

#One example of mechanism 21 is the commercial embodiment, Model 3892, made and sold by The Cookson Company, 700 Pennsylvania Avenue, San Francisco, Calif. 94107, and which is disclosed in U.S. Pat. No. 4,130,156.