| 摘要 |
PROBLEM TO BE SOLVED: To enable deflection scanning to be durable, quiet and also highly precise in spite of high speed revolution by positioning two rolling bearings in the operating posture with grease kept away upward from the balls and thereby maintaining a satisfactory lubricating condition for the rolling bearings. SOLUTION: A bearing unit 6 is constituted as independent unit parts. Initially, the outer wheels 20 are fixed at the part E against a fixing sleeve 12. In that case, the two rolling bearings 10 are assembled so that grease 24 comes above the balls 21. In addition, a retainer 23 is attached for the purpose of holding a constant distance between the balls 21 on the circumference. Then, the two inner wheels 22 are energized in the mutually approaching distance as shown by the arrow F, and are fixed on the rotary shaft 11 in the energized state. In the operating state of the device, both rolling bearings 10 are positioned with the grease 24 kept away upward from the balls 21. As a result, a sufficient base oil is supplied to the balls 21. |
