| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a method and an apparatus of detecting the motor rotation speed of a cargo handling vehicle for accurately detecting rotation speed at both low speed and high speed. <P>SOLUTION: The method includes steps of: determining rotation speed having a pulse interval measurement phase for detecting the motor rotation speed from a pulse interval outputted from a bearing sensor and a pulse counting phase for measuring the number of pulses outputted within a predetermined time from the bearing sensor to detect the motor rotation speed to be shifted from the pulse interval measurement phase to the pulse counting phase as a pulse count phase transition threshold; also determining the rotation speed to be shifted from the pulse counting phase to the pulse interval measurement phase as a pulse interval measurement phase transition threshold; being shifted to the pulse counting phase while the rotation speed exceeds the pulse count phase transition threshold during the pulse interval measurement phase; and being shifted to the pulse interval measurement phase while the rotation speed is below the pulse interval measurement phase transition threshold during the pulse counting phase. <P>COPYRIGHT: (C)2010,JPO&INPIT |
