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. 11, 2001
Filed:
Nov. 29, 1999
Jason Thomas Davis, Williamston, MI (US);
Jay Tolsma, Grand Ledge, MI (US);
Steven J. Haase, Okemos, MI (US);
General Motors Corporation, Detroit, MI (US);
Abstract
An improved fuel compensation method for a variable cam phase engine which predicts the phase of the cam at the midpoint of valve overlap and uses the predicted cam phase to compensate a base fuel pulse for the corresponding amount of diluent. If the cam phase is in transition to a desired value, the cam phase for purposes of compensation may be predicted based on the desired cam phase, current cam phase and its rate of change; otherwise, the cam phase is predicted based on the current cam phase. In a first interval of cam phase transition characterized by nonlinear change in cam phase, the cam phase is predicted by applying a nonlinear offset to the measured cam phase. In a second interval of cam phase transition characterized by substantially linear variation of cam phase, the cam phase is predicted by linear extrapolation of the measured cam phase, and limited to range bounded by the measured cam phase and the desired cam phase.