| 摘要 |
<p>A seal capable of increasing sealability under a special environment and being disposed in an annular space A where a rotating shaft (1) and a housing (2) are opposed to each other so as to partition the annular space axially into a vacuum space (B) and an atmospheric pressure space (C), wherein an axial contact width (WO) where a main lip (6) of the seal touches slidably with the rotating shaft (1) is equal to or longer than an axial contact with (W1) required to assure the minimum sealability for a sealing place and is equal to or shorter than an axial contact with (W2) where a sliding resistance against the rotating shaft is equal to an allowable upper limit value so that rotating characteristics for a rotary member are not affected, whereby a specified sealability can be assured.</p> |
