| 摘要 |
<P>PROBLEM TO BE SOLVED: To improve accuracy in determining normal rotation or reverse rotation of a rotary shaft based on a rotation signal. <P>SOLUTION: A pulse width WIPOS of a pulse-like rotation signal POS outputted by a crank angle sensor every time when a crankshaft (rotary shaft) of an internal combustion engine rotates by a unit crank angle is set so as to differ according to the rotational direction of the crankshaft, and the pulse width WIPOS and a threshold value SL are compared to thereby discriminate between the normal rotation and reverse rotation of the crankshaft (rotary shaft). Then, in a state that an engine rotation speed is increased, a state that an updating order of a cylinder with a piston determined to be in a predetermined position is normal, a state that an engine load is increased, a state that the engine is started to operate, a state that intake pressure is increased and a state that a voltage of a battery provided in the engine is increased, the crankshaft is assumed to be normally rotating, and the threshold value SL is updated based on an average value AVWIPOS of the pulse width WIPOS in that occasion. <P>COPYRIGHT: (C)2012,JPO&INPIT |
