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:
Oct. 30, 2018
Filed:
Oct. 23, 2015
Panasonic Intellectual Property Management Co., Ltd., Osaka, JP;
Abstract
An abnormality detection device includes: a coupling-capacitor having a first-end and a second-end coupled with a high-voltage circuit; a signal output unit; a signal extraction unit; and a signal input unit. The signal output unit is coupled with the first-end of the coupling-capacitor via a detection-resistor, and outputs an alternating-current inspection-signal. The signal extraction unit extracts the inspection-signal, as an extraction-signal, output between the detection-resistor and the coupling-capacitor. The signal input unit detects abnormality of insulation resistance of the high-voltage circuit based on a level of the inputted extraction-signal. The signal extraction unit includes a signal removing filter and a subtraction circuit. The filter removes a signal equal in frequency to the inspection-signal and passes low-frequency noises lower in frequency than the inspection-signal. The subtraction circuit outputs a differential signal, as the extraction-signal, between a signal having passed through the filter and a signal not having passed through the filter.