| 摘要 |
A seal apparatus is comprised of a seal ring 13 and a slinger 14 in combination to prevent foreign matter from progressing into the rolling bearing 6a. The amount of compression delta of the second seal lip 23, which occurs when the tip edge of the second seal lip 23 of the seal ring 13 comes in contact with the outside surface of the slinger 14, is at least 1/10 and up to 7/10 the height of the second seal lip 23 in the free state. In addition, the roughness of a portion of the outside surface of the slinger 14 which the tip edge of the second seal lip 23 comes in sliding contact with is from 0.2 mu m to 2.0 mu m in the arithmetic mean Ra, or is from 0.8 mu m to 8.0 mu m in the maximum height Ry. Consequently, a structure of a water pump is provided without increasing the cost thereof; or without enlarging the size to improve the durability of the water pump. <IMAGE> |
