| 摘要 |
<p>A machine tool (1) has a pair of guide rails (27) and a pair of upper and lower ball screws (28, 29). No forces are transferred between a beam (19) of a double column frame (7) and a movable unit (8). The guide rails (27) are spaced from each other and disposed on a bed (17), and the movable unit (8) is horizontally movably supported on the guide rails (27). The upper and lower ball screws (28, 29) are mounted respectively on upper and lower portions of the double column frame (7) for moving the movable unit (8) horizontally. Even when the beam (19) is deformed by flexing downwardly by gravity, the movable unit (8) moves stably and smoothly at a high speed to machine a workpiece highly accurately without being adversely affected by the deformation of the beam (19).</p> |
