The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Sep. 14, 1993
Filed:
Dec. 18, 1991
Duncan Chidley, Wildwood, NJ (US);
Paul J Allen, Ronks, PA (US);
Other;
Abstract
A method and system are provided for monitoring an item within a defined area and sounding an alarm if the item is removed from the area. A transmitter and transducers emit ultrasound which substantially saturates the area to be monitored. A security tag having a detector and alarm is attached to the items to be monitored within the area. Sensing circuits may be additionally provided to determine whether a security tag is being tampered with or removed by an unauthorized person. The security tag's alarm is sounded in the event that the receiver does not detect the ultrasound indicating that the monitored item is no longer in the monitored area. Additional alarms may be provided for indicating that the security tag has been tampered with or removed.