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. 30, 1995
Filed:
Aug. 31, 1994
Syuichi Nakano, Kariya, JP;
Tomio Sugiyama, Nagoya, JP;
Tomoji Fukaya, Kariya, JP;
Masatoshi Suzuki, Nagoya, JP;
Nippondenso Co., Ltd., Kariya, JP;
Abstract
An air fuel ratio detecting apparatus by which a stable oxygen ion limit current may be obtained, including a working electrode and a gas diffusion resistance layer laminated in this order on a first surface of a solid electrolyte. An ambient air introduction duct and an electric heater are laminated in this order on a second surface of the electrolyte. The gas diffusion resistance layer is composed of a gas permeation layer and gas shield layer, which is provided on a surface of the gas diffusion resistance layer. Since the surface of the gas permeation layer is covered by the gas shield layer, the gas to be measured enters into the gas diffusion resistance layer from only side faces of gas diffusion resistance layer. A cell is preferably baked in a one-piece manner. A porosity of the gas permeation layer is in a preferable range of from about 2 to about 60%, a thickness of the gas permeation layer is preferably in a range of from about 5 to about 300 .mu.m, and a porosity of the gas shield layer is preferably no more than 10%. Also, the periphery of the cell is preferably covered by a protective layer.