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. 25, 2003
Filed:
Jan. 24, 2002
Satoshi Motouji, Kyoto, JP;
Iichi Hirao, Kyoto, JP;
Teruyuki Hayashi, Nirasaki, JP;
Misako Saito, Nirasaki, JP;
Other;
Abstract
A chemical filter unit is made of a chemical filter and a filter life detection sensor . The filter life detection sensor is provided with an adsorption state detection sensor and a reference sensor to which a flow of air is blocked. The sensors and are made of the same filter material as the chemical filter with a pair of electrodes sandwiching the filter material. An oscillation circuit, in which the sensors and constitute a part of the oscillating conditions, detects changes in impedance of the sensors and based on the changes in oscillation frequencies. A measurement of the adsorption state detection sensor is corrected with a measurement of the reference sensor in order to remove effects of temperature and humidity, obtain a measurement corresponding to the amount of adsorption of chemical substances, and decide on the timing of replacing the chemical filter based on the corrected measurement.
Data source: USPTO (United States Patent and Trademark Office) public patent records. Weekly synchronization. How IDiyas builds this profile