| 摘要 |
PROBLEM TO BE SOLVED: To provide a plastic bearing that can restrain vibrations of a rotating shaft and allow the rotating shaft to rotate smoothly for a long time.SOLUTION: A plastic bearing includes a cylindrical body part 3 having a shaft hole 2 for rotatably holding a rotating shaft at a central portion. A plurality of first ribs 4 radially protrude from the outer surface of the body part 3, and a second rib 5 protruding in the circumferential direction is formed at a central portion in the longitudinal direction of the body part 3. A drum-shaped concave portion 6 is formed at a middle portion of the shaft hole 2. The first ribs 4 are formed in an arc shape so that they have the maximum height at the central portion in the longitudinal direction of the body part 3. The height of the second rib 5 is equal to the height of the first ribs 4 at the central portion in the longitudinal direction of the body part 3. |
