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:
Jan. 16, 2007
Filed:
May. 18, 2004
Masoud K. Zavarehi, Corvallis, OR (US);
Yang Liu, Dunlap, IL (US);
Conrad G. Grembowicz, Peoria, IL (US);
Masoud K. Zavarehi, Corvallis, OR (US);
Yang Liu, Dunlap, IL (US);
Conrad G. Grembowicz, Peoria, IL (US);
Caterpillar Inc, Peoria, IL (US);
Abstract
Individual cylinder output deviations from a normal operating engine cylinder are detected via an analysis of crank shaft speed fluctuations. In the detection phase, the engine is operated at a steady state low idle condition, and engine speed data is collected over a plurality of engine cycles. This data is then averaged, filtered and compared to expected engine speed data. A substantial deviation from the expected speed data in the region of crank shaft angles associated with an individual cylinder during its power stroke adjacent its top dead center position indicates a power level deviation in that cylinder. The magnitude of the power level deviation can then be assessed through a similar procedure where engine speed data is collected, averaged, filtered and compared to expected engine speed data when the engine is operating in a steady state rated condition.