| 摘要 |
PURPOSE:To give strength to a base sufficiently even in case of the generation of the moment by the weight of a stage and to prevent the deformation of the base, by arranging a movable part interposed with the gap of 1st and 2nd base members and capable of a relative movement with non-contact to the 1st and 2nd base members. CONSTITUTION:A movable part 16 supported with non-contact in the gap of 1st and 2nd base members 11, 13 is moved in this gap. The base easily becomes high at its stifness because of its being of a plane body different from a colum nar guide rail. So, the deformation is not caused actually even in case of the weight of the movable part 16 being given. Moreover the moment generation by the weight of the movable part 16 is difficult to be caused, even in case of a vertical movable stage, because of the two bases 11, 13 being of the struc ture of interposing the movable part 16, a sufficient strength is given to the bases 11, 13 without causing the movable part 16 weight increase if any and the deformations of the bases 11, 13 are prevented. |
