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Door control system and release mechanism

  • US 5,576,581 A
  • Filed: 11/17/1993
  • Issued: 11/19/1996
  • Est. Priority Date: 11/17/1993
  • Status: Expired due to Term
First Claim
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1. An electronic circuit for controlling a mechanical release mechanism for a rolling fire door comprising:

  • a mechanical release mechanism for releasing the rolling fire door when a condition in an outside environment requires that the door be released;

    digital logic means for processing signals which are indicative of the condition in the outside environment and for providing a trigger that will actuate the mechanical release mechanism in response to the condition, thereby releasing the rolling fire door;

    power means for providing regulated power to the electronic circuit in response to input power, the regulated power being used to operate the digital logic means; and

    power backup means interfaced to the power means for providing the regulated power for a predetermined time to the digital logic means in the event of an input power failure so that the digital logic means can be operated for the predetermined time during the input power failure and so that the fire door can be released in response to the condition in the absence of input power.

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