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. 16, 1997
Filed:
Apr. 22, 1996
Paul Alan Bauerle, Dewitt, MI (US);
Robert Francis Semrau, Ovid, MI (US);
John Norman Stockbridge, Lansing, MI (US);
General Motors Corporation, Detroit, MI (US);
Abstract
A maintenance method for periodically maintaining the operating condition of an exhaust gas recirculation valve for controlling recirculation of internal combustion engine exhaust gas from an exhaust gas path to an engine intake air path in which the valve is periodically driven to a maximum open position and then back to an initial position, such as a closed position when engine operating conditions are such that there is no driveability or emissions penalty associated with such valve maintenance and when sufficient battery drive voltage is available to drive the valve as required for maintenance thereof.