| 摘要 |
<P>PROBLEM TO BE SOLVED: To shorten a period for processing for restart when a stepping motor for a beam expander has already fallen into a biting-in state. <P>SOLUTION: When determining that the biting state occurs in the stepping motor 23 on the basis of a detection signal from a position sensor 26, a microprocessor 19 stores a flag indicating the biting state and the polarity of a detection signal in an EEPROM 29. When starting a device, the EEPROM 29 is referred to. If the flag indicating the biting state is stored and the polarity is different from that of a current detection signal, the stepping motor 23 is controlled to be driven decelerated more than usual. <P>COPYRIGHT: (C)2010,JPO&INPIT |
