Patent ID: 6681173
Filing Date: 2004-01-20
Classification: F02D,F02N,F02P

Abstract:
A method for determining angular crankshaft position prior to a cranking event of an internal combustion engine, the method comprising:upon issuance of an engine shutdown command, determining an initial crankshaft position based on a crankshaft position sensor; providing a rulebase for relating angular travel of a rotor in an accessory device to crankshaft angular travel; sensing angular travel of the rotor in the accessory device since issuance of the engine shutdown command until the engine reaches a resting position; accessing the rulebase to relate the value of the angular travel of the rotor in the accessory device to crankshaft angular travel and provide an incremental crankshaft angular travel relative to the initial crankshaft position at engine shutdown; calculating crankshaft position at the resting position based upon the initial crankshaft position plus the incremental crankshaft angular travel based on the angular travel of the rotor in the accessory device; storing the calculated crankshaft position corresponding to the resting position; and upon issuance of an engine re-start command, retrieving the stored crankshaft position corresponding to the resting position and provide quick and accurate engine control regardless of any dead-band in the crankshaft position sensor during low engine speeds.