| 摘要 |
PURPOSE:To perform highly accurate and reliable moving control of a table over a long stroke, by providing a voice coil at a linking part between a mobile table and a table driving mechanism. CONSTITUTION:A link rod 17 and a table 18 are linked between a link rod 17 and a mobile table 18 via a voice coil 21. The coil 21 incorporates an electromagnetic spring and a mechanical spring internally. The electromagnetic type spring expands or contracts axially in response to an electric input and is energized to a position balanced with the mechanical spring. On the other hand, axial change and uneven speed change of the table 18 are detected with a detector 20 and a difference of the comparison of them with respective objectives is defined as the electric input to drive the coil 21 and the operation of the table 18 is corrected. Thus,a minute correction can be performed for the coil 21 over the entire stroke. |
