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Magnetic door alarm with resettable delay

  • US 5,434,556 A
  • Filed: 01/12/1994
  • Issued: 07/18/1995
  • Est. Priority Date: 01/12/1994
  • Status: Expired due to Fees
First Claim
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1. An alarm system comprisinga proximity switch responsive to the opening of a door to produce an energizing signal;

  • a user actable switch;

    an electrical power source;

    an alarm means responsive to said energizing signal to provide a perceptible alarm signal; and

    a timer and logic means for generating a plurality of time periods for disabling said alarm signal, one of which allows a time period after actuation of said user actuable switch before opening said door to activate said proximity switch during which activation of said alarm means is prevented for a predetermined period, another of which allows a time period after opening said door to activate said proximity switch during which activation of said user actuable switch prevents activation of said alarm means for a predetermined period, another of which allows an extension of the period during which activation of said alarm means is prevented after the alarm means has been energized and then disabled by said user actable switch, and another of which allows for an extension of the period during which activation of said alarm means is prevented before the alarm means is energized.

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