| 摘要 |
PURPOSE:To make it possible to set a position at an arbitrary angle, by providing an arm rod having an axis in the direction crossing the axis of a motor shaft and providing a mount stand to the leading end of the arm rod and connecting the mount stand and the housing of a motor by bellows. CONSTITUTION:A disc shaped support member 17 is provided to the leading end of the motor shaft of a drive motor 14 and a vacuum bearing 18 is engaged with the support member 17 at the area separated from the axis thereof. The base part of the arm rod 19 is inserted in the vacuum bearing 18 and a mount stand 15 is provided to the leading end part of the arm rod 19. The movement of the mount stand 15 be comes precession and, when the motor shaft of the motor 14 rotates, the support member 17 rotates and the arm rod 19 rotates around the motor shaft. Because the mount stand 15 is restricted in its rotary motion by bellows 16, the mount stand 15 takes precession movement. |
