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:
Oct. 13, 1987
Filed:
Nov. 17, 1986
Edward J Jensen, Rochester, MI (US);
General Motors Corporation, Detroit, MI (US);
Abstract
A charge dilution control for an internal combustion engine subjects a combustion pressure signal to multiple switched capacitor bandpass filters with frequencies controlled in phase lock loop from engine speed to generate harmonic wave signals at frequencies which are constant multiples of the varying firing frequency. The amplitude ratio between the peaks of two harmonics, with one preferably the fundamental firing frequency, is used to control charge dilution apparatus such as EGR or variable valve lift to maintain a predetermined ratio. The harmonic compared to the fundamental may be a higher harmonic or a subharmonic. Ignition timing for the engine may be controlled to maintain a phase difference of zero between two of the higher harmonics such as the second and fourth.