| 摘要 |
PROBLEM TO BE SOLVED: To improve the sealing property of a seal under the special surroundings. SOLUTION: A seal is arranged in an annular space A between a rotary shaft 1 and a housing 2 so as to partition the annular space A into a vacuum space B and an atmospheric air pressure space C in the axial direction. In a main lip 6 of the seal, an axial contact width W0 to be slid for contact with the rotary shaft 1 is set in a range from the axial contact width W1 necessary to secure the minimum sealing property in relation to a part to be sealed to the axial contact width W2, in which the sliding resistance to the rotary shaft becomes a limited allowable upper value. |
