| 摘要 |
PURPOSE:To realize the highly accurate concentricity of a bearings and rotatability without causing a rise in price in a spindle that supports both ends of a spindle shaft, by providing a means for moving the bearins and making the concentricity of a pair of bearings adjustable. CONSTITUTION:A pair of bearings 23, 24 are arranged at both ends of the spindle shaft 15 and coupled with a base 1. The upper bearing 23 is fixed to the projected part 21a of a journal box 21, and the projected part 21a of the journal box 21 is reversely inserted to the base 1 through a gap (about 25mum), and the horizontal part 21b of the journal box 21 is placed on the base 1, and the journal box 21 is made fixable on the base 1 by screws 19, 20. Accordingly, it is movable in all directions in the horizontal plane of the base 1, and movable by about 50mum in the direction of an arrow 23 in a specified direction that passes a perpendicular line at the center of the lower bearing 24. The concentricity of the two bearings 23, 24 are set to high accuracy by adjusting the bearing so as to bring centers of the upper bearings 23 and lower bearing 24 to the same perpendicular line by the movement and can be fixed by screws 19, 20. |
