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:
May. 01, 2001
Filed:
Mar. 30, 1998
Shigeru Miyata, Aichi, JP;
Masashi Ando, Aichi, JP;
Hiroshi Inagaki, Aichi, JP;
Noboru Ishida, Gifu, JP;
Takafumi Oshima, Aichi, JP;
NGK Spark Plug Co., Ltd., Nagoya, JP;
Abstract
An NO,sensor capable of accurately determining the concentration of NO,contained in a gas to be analyzed (measurement gas) using a simple circuit. The NO,sensor includes a first measurement space and a second measurement space. The first measurement space communicates with the measurement gas via a first diffusion controlling layer, and the second measurement space communicates with the first measurement space via a second diffusion controlling layer. A first pumping current I,is controlled such that an output from a Vs cell is used as a reference voltage V,to control the amount of oxygen flowing into the second measurement space at a constant level. A constant voltage is applied to the second pumping cell so as to decompose the NO,component of the measurement gas contained in the second measurement space, and to pump out the resulting oxygen from the second measurement space. Accordingly, the concentration of NO,contained in the measurement gas can be obtained from second pumping current I,. The electrode of the Vs cell located on the side of the first measurement space is formed around the periphery of or on a portion of the diffusion controlling layer of the Vs cell. As a result, the amount of oxygen flowing from the first measurement space into the second measurement space can be accurately determined by means of the Vs cell. Also, the NO,concentration can be accurately determined without the need for compensation.