| 摘要 |
PROBLEM TO BE SOLVED: To carry out the sealing between a casing and a cover securely, by providing two thin circumferential lips, and a lip between them, whose cross sections are different from a circular form, in the area positioning to the side surface of a plane a ring is positioned. SOLUTION: A casing 1 having a globular seat 2 to receive the outer ring of a bearing 3 has a circular hole 4, and a cover 5 is provided to be held to a snap stopper receiver. A circular edge 6 projecting in the inner direction of the cover 5 is provided, and the cover 5 is maintained at the correct position by the circular edge 6 and a circular hole 4 for engaging a snap stopper. The cover 5 consists of a pedestal 7 for a circular seal gasket 8 approaching to the projecting edge 6. And a seat 7 is a form of nondeforming, and has a cross section inscribeable to a trapezoid, one side surface of the quadrangle consists of two projecting parts 81 and 82 forming a groove, its opposing side surface faces the casing 5, and it has three projecting parts 83, 84, and 85 to form two grooves. |
