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:
Jul. 20, 1993
Filed:
Oct. 28, 1992
Ross D Pursifull, Dearborn, MI (US);
Julie A Konrad, Dearborn, MI (US);
Robert W Ridgway, Royal Oak, MI (US);
Ford Motor Company, Dearborn, MI (US);
Abstract
A heated exhaust gas oxygen sensor assembly that automatically detects whether the heater in the assembly is malfunctioning. The assembly includes an oxygen sensor, heater, impedance sensor, and controller. The oxygen sensor detects the relative oxygen concentration in the exhaust gas of an internal combustion engine and issues signal along a pair of output leads. The heater physically warms the oxygen sensor. The impedance sensor is interconnected to the output leads of the oxygen sensor and provides an impedance measurement to the controller. The controller compares the impedance to a predetermined threshold value to judge the effect of the heater in physically warming the sensor. If the impedance is above a predetermined threshold, the controller determines that the heater is not operating properly and issues an alarm signal.