| 摘要 |
PROBLEM TO BE SOLVED: To improve rigidity and abrasion resistance in a ball bearing so that the bearing may withstand high-speed rotation. SOLUTION: A ball bearing 4 is fitted to the center shaft 3 of a motor 3 and, at the same time, a housing 5 is fitted to the bearing 4 and a polygonal mirror 6 is attached to the housing 5. The rolling body 4b and outer ring 4c of the bearing is respectively made of a ceramic and a tungsten alloy. When the bearing 4 is constituted in the above-mentioned way, the overall rigidity and abrasion resistance of the bearing are improved as compared with the conventional constitution using the bearing steel. In addition, since the rolling contact section of the bearing 4 is made of a different kind of material, the bearing can exhibit superior durability and reliability by preventing seizure.
|
