| 摘要 |
PURPOSE:To permit a device so as to exchange an upper lap main unit by labor of small number of persons in a short time by providing a holding means which constitutes an upper lap structure of an upper lap supporter and the upper lap main unit having a magnet member for mounting the upper lap main unit to and removing it from this upper lap supporter. CONSTITUTION:When an upper lap main unit 27 is replaced, an upper lap struc ture 25 is removed from a position opposed to a bottom lap structure 12. Next rotating each adjusting screw thread 38, a holding means 35 moves its magnet member 37 to the upper to be separated from the upper lap main unit 27. In this way, the upper lap main unit 27 is removed from an upper lap supporter 26. After the removal, a new or repaired upper lap main unit 27 is mounted to the upper lap supporter 26. Subsequently, rotating the adjusting screw thread 38 in a reverse direction, lowering the magnet member 37 and attracting the upper lap main unit 27 by magnetic force of this magnet member 37 to be pressed and fixed to the upper lap supporter 26, the upper lap main unit 27 completes its replacement. |
