| 摘要 |
PROBLEM TO BE SOLVED: To provide a method of controlling beams to return to an original position by a multiple shaft drive system capable of preventing a beam torsion caused by time difference in searching the original position of each shaft, in a multiple shaft drive system transferring the beam in a parallel direction by collaborating operation of a plurality of transferring mechanism. SOLUTION: In a multiple shaft drive system transferring a beam in parallel direction by collaborating operation of a plurality of transferring mechanism, when the beam is detected in a slow sensor area prepared near the original position (Judgement 1), the beam is once transferred in parallel direction to the outside area of the slow sensor area (Step 21, Judgment 22), is inverted from that position (Step 23), and is made to search for the original position (Step 5 or after). |
