| 摘要 |
<p>PURPOSE:To make it possible to make a moving table return automatically within the allowable moving range of the table when the moving table exceeds its allowable moving range and a drive power to a driving device for driving the table is cut off. CONSTITUTION:A movable element 46 is placed along a linear guide 55 in a frame 44 and the element 46 is energized to the side of a sidewall 44a by a tensile coil spring 47. When a scanning stage 9 is moved to the side of the element 46, the element 46 is moved in a direction -Y and when an operating plate 49 fixed by the element 46 comes into contact with a microswitch 50, a drive current to a linear motor for driving the stage 9 is cut off. After that, the stage 9 is pushed in a direction +Y by the element 46 to return in its allowable moving range 51 and the microswitch 50 is returned in a state that it is turned on.</p> |
