Release mechanism and method with alarm circuit
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United States of America Patent
Stats
-
Jan 21, 1992
Issued Date -
N/A
app pub date -
Dec 14, 1990
filing date -
Dec 1, 1989
priority date (Note) -
Expired
status (Latency Note)
Importance
Abstract
Release mechanism and method for fire doors and the like. The door is normally held in an open position by an electrically energized actuator and is released for closing upon deenergization of the actuator. An eneergizing current is supplied to the actuator from a source to energize the actuator, and a limited amount of energy from the source is stored in an element such as a capacitor. Upon interruption of the current from the source to the actuator, the actuator is energized with the stored energy to prevent the door from closing for a limited period of time after the current is interrupted. An alarm circuit is included in some embodiments to porivde a warning when the current has been interrupted and the door is about to close.
First Claim
Family
International Classification(s)
Cited Art Landscape
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