Self-testing security sensor for monitoring closure of vault doors and the like

Patent · Tue May 27 04:00:00 EDT 1997

OSTI ID:870972

Cawthorne, Duane C ^[1]

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1. Amarillo, TX

A self-testing device is provided for a monitoring system for monitoring whether a closure member such as a door or window is closed. The monitoring system includes a switch unit mounted on the frame of the closure member being monitored and including magnetically biased switches connected in one or more electrical monitoring circuits, and a door magnet unit mounted on the closure member being monitored. The door magnet includes one or more permanent magnets that produce a magnetic field which, when the closure member is closed, cause said switches to assume a first state. When the closure member is opened, the switches switch to a second, alarm state. The self-testing device is electrically controllable from a remote location and produces a canceling or diverting magnetic field which simulates the effect of movement of the closure member from the closed position thereof without any actual movement of the member.

• Research Organization: MASON & HANGER CORP
• DOE Contract Number: AC04-91AL65030
• Assignee: United States of America as represented by United States (Washington, DC)
• Patent Number(s): US 5633626
• Application Number: 08/520,634
• OSTI ID: 870972
• Country of Publication: United States
• Language: English

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