| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide a long-life bearing for a motor with a rotary encoder in which a retainer is installed, which can realize low torque performance, grease-leakage resistant performance, dust-resistant performance, and space saving simultaneously at low cost, which can extend the life of grease lubrication, which can realize high high-speed rotation performance peculiar to an iron plate retainer, and which can secure a larger bearing stationary space than a resin retainer. <P>SOLUTION: The retainer 4 has pockets 50 in a plurality of positions in the circumferential direction, and each of the pockets 50 has a plurality of balls. The ring-shaped inner surface of each of the pockets 50 has a concave curved surface so that the part on the inner diameter side than the ball arrangement pitch circle PCD has a smaller diameter as it moves closer to the opening edge on the inner diameter side of the retainer. Then a concave part 54 is provided on the inner surface of each of the pockets 50, and the concave part 54 is extended from the opening edge on the inner diameter side of the retainer to the outer diameter side of the retainer. A membrane made of either a resign, elasticity metal, or a solid lubricant may also be formed on the guide surface of the ball of the pocket 50. <P>COPYRIGHT: (C)2009,JPO&INPIT</p> |
