| 摘要 |
PURPOSE:To minify variation of gap and pre-load due to temperature difference by respectively providing annular members between inner and outer races of a pair of face-to-face duplex angular ball bearings so as to cancel differential thermal expansion due to temperature difference between the inner and outer races by difference of thermal expansion coefficient between annular members. CONSTITUTION:In a face-to-face duplex angular ball bearing under pre-loaded condition, the temperature of outer races 3a, 3b is higher than that of inner races 2a, 2b due to rotation, the outer races 3a, 3b are thermally expanded in the radial direction and in the axial direction, and the quantity is larger than that of the inner races 2a, 2b so as to reduce the pre-load. Meanwhile, the thermal expansion coefficient of an inner annular member 8 is larger than that of an outer annular member 9, the temperature is raised from the ordinary temperature though it is lower than that of the outer races 3a, 3, and hence the member 8 is sufficiently thermally expanded so as to apply force on the two inner races 2a, 2b in the separating direction. The force is applied on the inner races 2a, 2b in the direction of pressing the balls 4a, 4b so as to increase the pre-load. These actions are mutually cancelled and hence variation of pre- load is minified. |
