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:
Jan. 01, 2019
Filed:
Feb. 28, 2014
Panasonic Intellectual Property Management Co., Ltd., Osaka, JP;
Kenichi Asanuma, Osaka, JP;
Atsushi Yamamoto, Kyoto, JP;
Hiroshi Yamamoto, Osaka, JP;
Hiroshi Kanno, Osaka, JP;
Abstract
A foreign object detector detects a metallic foreign object between a first resonator and a second resonator which is composed of a parallel resonant circuit including a coil and a capacitor. The foreign object detector includes the first resonator; an oscillator circuit capable of oscillating at a first frequency (f1) which is lower than a resonant frequency (fr) of the second resonator and at a second frequency (f2) which is higher than the resonant frequency (fr); and a measurement circuit to measure changes in input impedance of the first resonator. The measurement circuit detects a metallic foreign object between the first resonator and the second resonator based on: changes in input impedance of the first resonator as measured by the measurement circuit while the oscillator circuit is oscillating at the first frequency f1; and changes in input impedance of the first resonator as measured by the measurement circuit while the oscillator circuit is oscillating at the second frequency f2.