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:
Apr. 08, 1997
Filed:
Nov. 20, 1995
Applicant:
Inventors:
David K Bidner, Livonia, MI (US);
Glenn A Zimlich, Dearborn Heights, MI (US);
Daniel V Orzel, Westland, MI (US);
Assignee:
Ford Motor Company, Dearborn, MI (US);
Attorneys:
Primary Examiner:
Int. Cl.
CPC ...
F02D / ;
U.S. Cl.
CPC ...
123481 ;
Abstract
A method for maintaining clean spark plugs in a variable displacement engine in which at least one group of cylinders is disabled in response to the engine load being less than a predetermined value. A first timer determines the maximum period that the engine may be operated with the first group of cylinders being disabled. A second timer controls the period of time the previously deactivated cylinders need to be reactivated to clean the spark plugs, after being deactivated for the maximum period of time.