| 摘要 |
PURPOSE: To vary preload in less volume and in high precision by furnishing first and second angular contact bearing means to support a shaft in the opposite axial directions, a means to make them in the maximum preload state and a means to reduce them down to a desired preload state against it. CONSTITUTION: A first angular contact bearing 16 has an inner ring 24 fixed against a rotation axis 10 and an outer ring 26 fixed against a housing 14. An inner ring 28 of a second angular contact bearing 18 is fixed against the rotation axis 10, and only an outer ring 30 of the bearing 18 can displace in the axial direction so as to keep the bearings 16, 18 in a preloaded state. A preloader 32 applies force on the outer ring 30 of the bearing 18, the bearing 16, 18 are kept under the maximum preload state. Preloader deflection is caused by force applied on the preloader 32 through the outer ring 30 of the bearing 18 from a working means 36, and initial deflection (preload) of balls and bearing rings of the bearings 16, 18 is minimized. As rigidity of the preloader 32 is larger than rigidity of the bearings 16, 18, it is possible to precisely vary the preload. |
