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:
Jan. 06, 2004
Filed:
Sep. 27, 2001
Hiroshi Isomura, Nagoya, JP;
Takayoshi Atsumi, Nagoya, JP;
Koji Shiono, Nagoya, JP;
Masamine Takagi, Nagoya, JP;
NGK Spark Plug Co., Ltd., Aichi, JP;
Abstract
The oxygen sensor of the present invention has excellent durability capable of effectively preventing contamination with lead or the like for a detection electrode even in low temperature exhaust gases, and having stable response over a long period of time. The contamination preventive layer provided in the sensor device comprises composite powders having coarse powders covered therearound with fine powders, and hollows not filled with fine powders are scattered in gaps among the composite powders. Both the coarse and fine powders comprise ceramic powders. Further, it is particularly preferred that the ceramic powders are powders of a titania powder having a peak at 1 &mgr;m or less and a composite ceramic powder containing alumina such as spinel having a peak at 10 &mgr;m or more. The contamination preventive layer can be formed by coating a slurry containing ceramic powders of different specific surface areas, an organic binder and a solvent such as methanol on the surface of the electrode protection layer followed by drying.