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:
Sep. 30, 1980
Filed:
Jan. 22, 1979
Achyuta Achari, Detroit, MI (US);
Elmer T Heiney, III, Huntington Woods, MI (US);
Ford Motor Company, Dearborn, MI (US);
Abstract
An improved sensor having a ceramic element that undergoes a change in an electrical characteristic in response to a change in the partial pressure of oxygen in a mixture of gases to which the ceramic element is exposed. Sensors of this type are used to detect the air-fuel ratio of mixtures supplied to internal combustion engines. Prior art titania and zirconia sensors are characterized by little change in their respective electrical characteristics at operating temperatures below about 350.degree. C. A charge transfer material, platinum, has been applied to the ceramic element to facilitate or make possible the electron transfers required for sensor operation. Loss of the platinum charge transfer material by vaporization, as the result of operation at normal elevated temperatures, has been discovered to be the cause of a loss of sensor response at low sensor operating temperatures. The improved sensor has a charge transfer material comprised of an alloy of platinum and rhodium. This alloy, which preferably is 90% platinum and 10% rhodium, reduces the minimum temperature of operation for the sensor and substantially eliminates the aforementioned vaporization loss of the charge transfer material.