| 摘要 |
A motor of long life and high precision in its rotation wherein the variation on the rotation and the noises generated thereby are suppressed by maintaining the radial clearance between the components of the bearing device even if the thermal expansion of the components is caused by rising the temperature thereof. A motor having a rotational member 7 rotatably supported through a bearing device provided on a base member 1 thereof, said bearing device including a shaft 16, a cylindrical outer ring member 17 surrounding the shaft, a plurality of balls of the first and the second rows interposed between the shaft and the outer ring member, and a low expansion member 22 press fit around the outer periphery of the outer ring, wherein the low expansion member is made of a material lower in its coefficient of linear expansion than that employed for the outer ring.
|
