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. 25, 1993
Filed:
Dec. 11, 1990
Kouichi Hoshi, Susono, JP;
Makoto Suzuki, Mishima, JP;
Toyota Jidosha Kabushiki Kaisha, Toyota, JP;
Abstract
An apparatus for controlling a heater for heating an oxygen sensor provided in an exhaust gas flow passage of an internal combustion engine disposed in an automotive vehicle, includes an operating condition detecting unit for detecting a predetermined operating condition of the internal combustion engine, and a resistance/power detection unit for detecting a heater resistance value of the heater and an amount of power supplied to the heater when the internal combustion engine is in the predetermined operating condition. The apparatus also includes a power control unit for comparing the heater resistance value detected by the resistance/power detection unit with a target resistance value and for supplying the heater with power supplied from a battery in a definite-resistance control mode in which the heater resistance value is controlled to become equal to the target resistance value, a resistance value correction unit for correcting the target resistance value so that a difference between the amount of power detected by the resistance/power detection unit and a standard amount of power becomes equal to zero, and a storage unit for storing the target resistance value corrected by the resistance value correction unit as a learning value. Further, the apparatus includes a storage state judgment unit for judging whether or not the the learning value is correctly stored in the storage unit, and a stop unit for stopping the power control unit to supply the heater with power in the definite-resistance control mode.