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:
Mar. 17, 2015
Filed:
Aug. 11, 2011
Justin M. Johnson, Oakdale, MN (US);
Lori-ann S. Prioleau, St. Paul, MN (US);
Brinda B. Badri, Woodbury, MN (US);
James C. Vanous, Roseville, MN (US);
Robert D. Lorentz, North Oaks, MN (US);
Jacob D. Chatterton, St. Paul, MN (US);
Steven J. Perron, St. Paul, MN (US);
Donald R. Battles, Arden Hills, MN (US);
Justin M. Johnson, Oakdale, MN (US);
Lori-Ann S. Prioleau, St. Paul, MN (US);
Brinda B. Badri, Woodbury, MN (US);
James C. Vanous, Roseville, MN (US);
Robert D. Lorentz, North Oaks, MN (US);
Jacob D. Chatterton, St. Paul, MN (US);
Steven J. Perron, St. Paul, MN (US);
Donald R. Battles, Arden Hills, MN (US);
3M Innovative Properties Company, St. Paul, MN (US);
Abstract
A wetness sensor includes a substrate that carries a tuned RF circuit. The circuit includes a conductive pattern applied to the substrate, a capacitor, and a jumper all disposed on a same side of the substrate. The conductive pattern includes an inductive coil, and an inner and outer terminus. The jumper electrically couples the inner terminus to the outer terminus. The jumper also includes a frangible link which, when contacted by a target fluid, produces a drastic change in the operation of the RF circuit. The drastic change can be interpreted by a remote reader as a 'wet' condition. Contact of the frangible link by the target fluid may change the impedance or resistance of the RF circuit by at least a factor of 5, 10, 100, or more, and/or may cause the frangible link to disintegrate to produce an open circuit, and/or may substantially render the RF circuit inoperative.