| 摘要 |
PURPOSE:To simplify construction of a stage driving gear in an XY table, by constituting the table forming in a continuous state an X axis loop and a Y axis loop by a single winding unit and switching the operative condition of a control rotary unit by a brake means. CONSTITUTION:When an X axis loop 12 is controlled, forcedly stopping rotation of a control rotary unit 17 by a brake means 19, a winding unit 11 is unmovably restricted on the peripheral surface of the control rotary unit 17. Under this condition, if a motor 21 is started, tensile force acts on a fixed end of either the control rotary unit 17 or an arm 3 of the winding unit 11, moving the arm 3 in that direction. If the motor 21 switches its driving rotary direction, the arm 3 moves in a reverse direction. On the other hand, when Y axis loops 13A, 13B are controlled, releasing the brake means 19, the control rotary unit 17 is switched to a condition that it can rotate in the same direction to the winding unit 11. Under this condition, if the motor 21 is started, tensile force acts on a loop guide 16 on a stage 5 so as to pull out one of the loops to the side of the X axis loop 12, and the loop guide 16 is moved. |
