Title: Magnetic emergency exit door lock with delayed opening

Abstract: A magnetic emergency exit door locking system includes a magnetic lock with an armature securred to an emergency exit door and a coil to the lintel of the door. The coil is connected to a power supply and keeps the door locked as long as the power supply applies current thereto. A drop-out relay is disposed in the line between the power supply and coil to interrupt current to the coil when operated. The drop-out relay is operated by a switch which is tripped upon pushing the push-bar on the door. In order to prevent immediate opening of the door upon pressing the push-bar, a timer is disposed between the switch and the drop-out relay to delay unlocking of the door for a selected interval having a duration of, perhaps, fifteen (15) to forty (40) seconds. An alarm sounds during this interval to give notice that someone is trying to open the door.

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Inventors: Logan, Jr., Emanuel (Silver Spring, MD, US)

Application Number: 051724
Filing Date: 1979-06-25
Publication_date: 1981-03-24
Assignee: Reliable Security Systems, Inc. (Columbus, OH); Reliable Security Systems, Inc. (Columbus, OH)
Primary Class(es): 292/251.5 292/21, 292/92
Other Classes:
US Patent Ref:

3431002	Mar, 1969	Melgaard	292/251.
3576119	Apr, 1971	Harris	292/144.

Other Refs:
Primary Examiner: Moore, Richard E.
Assistant Examiner:
Attorney: Quaintance, Murphy & Richardson