| 摘要 |
PURPOSE:To lessen the variation in the speed of X-Y stage by providing a guider to guide the movement of a feed screw nut while preventing the rotation of the feed screw nut drive-connected with X-Y stage. CONSTITUTION:In the central part of the upside of a feed screw nut 3, two rotation-preventing bearins 9A and 9B are fixed to the upside of the nut 3 by a bolt 10. The rotation-preventing bearing 9A comes into contact with the projected inside of a guider 11A on the left side of the Fig. to prevent the rotation of the nut 3 toward counterclockwise direction. On the other hand, the rotation- preventing bearing 9B comes into contact with the projected inside of the guider 11B on the right side of Fig. to prevent the rotation of the nut 3 toward clockwise direction. Thus, even when feed screw 2 turns in either direction, no rotatiok occurs in the feed screw nut 3. |
