| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide a laser marking device by which an abnormal rotation of galvanomirrors due to the deterioration of a ball bearing or the like is correctly and surely detected. <P>SOLUTION: The load torque of a driving motor 40 varies due to the abnormal rotation of galvanomirrors 21X and 21Y, a driving current I flowing through a driving coil 40c varies compared to a normal state. Thus, if the level of a measurement signal V2 is not within the range between a first reference value and a second reference value when the measurement signal V2 which is I/V-converted according to the driving current I is outputted from a current measurement circuit 43, and a driving signal V1 for turning the galvanomirrors 21X and 21Y at a constant speed is given to galvanodriving devices 23X and 23Y, a high level detection signal V3 is outputted from a comparator circuit 44. Further, pilot lamps corresponding to the galvanodriving devices 23X and 23Y which receives the high level detection signal V3 from a driving control part 30, thus an operator recognizes an abnormality of turning of the galvanomirrors 21X and 21Y. <P>COPYRIGHT: (C)2003,JPO</p> |
