SIMPLIFIED FLYWHEEL SPEED FLUCTUATION MONITORING AND CONTROL
Original Publication Date: 1991-Apr-01
Included in the Prior Art Database: 2001-Dec-05
U.S. patent 4,936,277 Deutsch et al describes a method for using the cyclic speed fluctuation to measure, diagnose and control the operation of an internal combustion engine. This system uses the vector multiplication of a predefined weighting vector by an instantaneous cylinder speed/power vector signal to obtain a scalar representing a parameter of the engine. The speed/power vector signal is obtained from a rotating toothed wheel position signal and comprises elapsed time of tooth periods for each cylinder cycle. A cylinder cycle consists of the angular period of the engine starting at a predefined time before top dead center (BTDC) and ending at a predetermined time after top dead center (ATDC). Parameters which can be measured are related to cylinder power, presence of knock and the existence of certain types of faults.