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:
Nov. 04, 2003
Filed:
Mar. 29, 2001
James D. Ward, Royal Oak, MI (US);
Alton L. Schuessler, Flushing, MI (US);
Kenneth M. Simpson, Howell, MI (US);
Hallett D. Breidenbach, West Bloomfield, MI (US);
Delphi Technologies, Inc., Troy, MI (US);
Abstract
An improved method of diagnosing shaft sensor failure in a reciprocating internal combustion engine verifies engine rotation by sensor information responsive to dynamic variation in engine air intake that occurs during engine rotation. Failure of the shaft sensor is diagnosed when the dynamic variation in engine air intake is detected in the absence of a shaft sensor signal. The sensor information used to detect the dynamic variation in intake air may be obtained from either a mass air flow sensor disposed in a throttle passage of the engine, or from a pressure sensor disposed in an intake manifold of the engine, and virtually all current engine control systems utilize at least one of these sensors. The dynamic variation is detected by recognizing rising and falling segments of the signal waveform, by comparing the relative manifold pressure to predetermined maximum and minimum values, or by using a derivative of the signal waveform to recognize its inflection points.