FIRE ACTUATED RELEASE MECHANISM TO SEPARATE ELECTRONIC DOOR LOCK FROM FIRE DOOR

摘要

A release mechanism is actuated by the heat of a fire to electrically and mechanically disconnect electrical wiring from an electronic lock having a plastic housing. The electronic lock is mounted on a fire door and as it is heated by a fire on the opposite side of the fire door, mounts that hold the lock melt, releasing the electronic lock to drop away from the fire door and prevent ignition of the plastic housing. The release mechanism may use shape memory alloy wire to contract and disconnect a ribbon cable. Solder connectors may also be used to disconnect wires. Intumescent material that expands when heated is used to drive the lock mechanism away from the fire door and insulation is used to control the timing of melting.

主权项

1. An electronic door lock comprising:
a housing mechanically mountable to a first side of a fire door; wires extending out of the housing and into the fire door; a circuit board mounted within the housing, the wires being connected to the circuit board; a fire actuated mechanical release for mechanically releasing the housing from a first side of the fire door when a second side of the fire door is exposed to a fire; and a fire actuated electrical release for electrically and mechanically disconnecting the wires from the circuit board when the second side of the fire door is exposed to a fire; the mechanical release and electrical release cooperating to release the housing from connection to the first side of the fire door and allow the housing to move sufficiently away from the fire door to prevent ignition of any components of the electronic door lock when the second side of the fire door is exposed to a fire.