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:
Dec. 31, 2002
Filed:
Sep. 05, 2000
Frank Gonzales, Jr., Garden City, MI (US);
Ford Global Technologies, Inc., Dearborn, MI (US);
Abstract
A method of determining the stopping position of an internal combustion engine infers the angular position of the engine's crankshaft by analyzing the periodic waveform of an output signal produced by a crankshaft position sensor. When the engine is turned off and begins to slow to a stop, an inference routine is commenced in which the ratio of the amplitude of the signal to the time of successive half periods of the waveform is calculated. The amplitude-to-time ratio is used in secondary ratio calculations to obtain ratio values that are then compared to a preselected constant. The result of the ratio value-to-constant comparison reveals whether the crankshaft is continuing to turn in the same direction, or has stopped and reversed its direction. A “bookkeeping” record of the current crankshaft angle is incremented or decremented by a predetermined value each time the ratios are calculated until the engine had stopped. Without the present invention method, the changes in engine rotational direction cannot be detected and simply monitoring the raw signal would give unreliable stopping position information because of the missed reversal(s).