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:
Feb. 10, 1998
Filed:
Nov. 22, 1996
Zhijian James Wu, Rochester Hills, MI (US);
Anson Lee, St. Clair, MI (US);
Chrysler Corporation, Auburn Hills, MI (US);
Abstract
The present invention provides a method of detecting internal combustion engine misfiring. The method includes mixed rate sampling of crankshaft angular velocity for a plurality of cylinder firing events to generate a crankshaft angular velocity signal and a cylinder firing synchronization signal. The apparatus for executing the method comprises a crankshaft in operative relation with the internal combustion engine. A crankshaft sensor wheel is rotatably triggered by the crankshaft and includes a plurality of predetermined sensor indicators disposed at least at two different angular widths. A sensor is positioned adjacent to the wheel for sensing the passage of each indicator in producing a signal pulse having a duration corresponding to the angular width of the sensed indicator in response thereto. A counter determines the time intervals between signal pulses generated by the sensor including a synchronization signal time interval and an RPM signal time interval. The synchronization signal time interval is then utilized to calculate a plurality of crankshaft angular velocities for a plurality of RPM indicators replaced by a synchronization indicator. A misfire detector then determines if a misfire has occurred by interpreting a series of data points developed from the plurality of crankshaft angular velocities.