| 摘要 |
<p>PROBLEM TO BE SOLVED: To maximize the life by suppressing decrease in a contact area having sufficient contact pressure to the curved surface of a neck part even though abrasion by sliding friction with the curved surface of the neck part progresses. SOLUTION: In the radial lip 24 of this cup seal 21, which is brought into contact with the neighborhood of the starting end of the curved surface 12 of the neck part of the spider shaft 3 of an universal joint, a thinned part 24a for flexing is arranged just before a position being a contact starting end to the curved surface 12 of the neck part so that an end side beyond the position being the contact start end is easily bent along the curved surface 12 of the neck part, and also the thickness of the end side being a contact terminal to the curved surface 12 of the neck part is arranged thicker than the thinned part 24a for flexing.</p> |
