Patent ID: 6583722
Filing Date: 2003-06-24
Classification: A61F

Abstract:
A monitored article having a monitored portion, comprising:an interrogator located in operative proximity to said monitored portion; a status signaling device disposed relative to said monitored portion for communicating a change in status of said monitored portion, said status signaling device comprising: a sensor which can indicate a change of state that occurs when said monitored portion of said article changes from a first condition to a different, second condition, said sensor indicating said change of state by providing a change of electronic impedance that occurs when said monitored portion changes from said first condition to said second condition; and a passive electronic transponder which is cooperatively connected with said sensor; wherein said transponder is configured to receive electromagnetic input energy which has been provided to said transponder from said interrogator at a predetermined input frequency; said transponder is con to respond with operative indicator data when said monitored portion is in said second condition; said transponder includes an electronically-tuned resonant circuit which is operatively tuned to said input frequency; said indicator data includes a change in an amount of energy reflected through said transponder, such change in reflected energy provided when said monitored portion changes from said first condition to said second condition; said transponder configured to communicate an output energy away from said monitored portion, said output energy including at least a portion of said input energy, and said output energy configured to carry said indicator data; an output receiver configured to electronically acquire said output energy and indicator data from said transponder; a detector in communication with said output receiver and configured to react to a threshold value of the amount of energy reflected through said transponder in said indicator data; and an annunciator in communication with said detector and configured to announce a presence of said threshold value of energy reflected through said transponder.