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. 31, 1989
Filed:
Dec. 28, 1988
Toyohei Nakajima, Wako, JP;
Toshiyuki Mieno, Wako, JP;
Honda Giken Kogyo Kabushiki Kaisha, Tokyo, JP;
Abstract
An oxygen concentration-sensing device includes an oxygen concentration-sensing element formed by an oxygen-pumping element and a cell element, each composed of an oxygen ion-conductive electrolytic member and a pair of electrodes having the member interposed therebetween. The two elements define a gas diffusion-limiting zone therebetween. A current-to-voltage converter circuit has an input terminal connected to the junction between mutually connected ones of the electrodes. A first amplifier generates an output having a level variable in response to the difference between a potential at a conversion output terminal of the current-to-voltage converter circuit and a potential at the other electrode of the cell element, and applies the output to the other electrode of the oxygen-pumping element. A second amplifier has an input thereof connected to the above junction and generates an output proportional to current flowing in the oxygen-pumping element. The current-to-voltage converter circuit imparts a higher gain to the first amplifier when pumping current flowing in the oxygen-pumping element is in a high frequency range.