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. 15, 1997
Filed:
Apr. 01, 1996
John T Carroll, III, Columbus, IN (US);
Thomas L Bailey, Columbus, IN (US);
Cummins Engine Company, Inc., Columbus, IN (US);
Abstract
An apparatus and method for determining start of fuel injection (SOI), preferably in an open nozzle fuel injection system, comprises means for obtaining injector train load data as a function of crank shaft timing, and a computer for sampling the data, performing a smoothing operation thereon, computing a first derivative of the smoothed injector train load data samples with respect to crank shaft timing, computing a maximum value of the first derivative, computing a predefined fraction of the maximum value of the first derivative, and mapping the predefined fraction of the maximum value of the first derivative to its corresponding crank shaft angle, wherein the corresponding crank shaft angle defines the crank shaft angle, measured in degrees relative to piston top dead center, at which SOI occurs. In an alternative embodiment, the smoothing operation and computation of the first derivative may be combined into a single operation.