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:
Dec. 01, 2009
Filed:
Sep. 19, 2007
Shinji Kumazawa, Aichi, JP;
Masayuki Motomura, Aichi, JP;
Shinji Kumazawa, Aichi, JP;
Masayuki Motomura, Aichi, JP;
NGK Spark Plug Co., Ltd., Aichi-Ken, JP;
Abstract
An environmental-state determination apparatus includes a pair of detection electrodes which provide therebetween a capacitance which changes in accordance with a state of a surrounding environment, for example, the level of a liquid. A detection signal is input to a signal passage connected to the detection electrodes. A first capacitance parameter representing the capacitance of the detection electrodes is detected on the basis of a signal output from the signal passage in the connected state. The detection signal is input to the signal passage from which the detection electrodes are disconnected. A second capacitance parameter representing the capacitance of the signal passage is detected on the basis of a signal output from the signal passage in the disconnected state. The first capacitance parameter is corrected by subtracting therefrom the second capacitance parameter. The state of the surrounding environment is determined on the basis of the corrected first capacitance parameter.