| 摘要 |
PROBLEM TO BE SOLVED: To avoid a rapid ambient destruction of an object space to be sealed at a sealing device having a plurality of seal rings. SOLUTION: The sealing device 8 partitions an annular space between an outer cylinder 4 and a rotation shaft 6 rotatably inserted through a center thereof to two parts in an axial direction. The sealing device 8 has a plurality of seal rings 20, 30 axially arranged at the outer cylinder 4 in adjacent to each other, engaged and fixed thereto and contacted with the rotation shaft 6, respectively. Any one seal ring 30 is set to a shorter life than that of the other seal ring 20. Thereby, since a life of the other seal ring 20 is not finished even if a life of one seal ring 30 is finished, an ambient of an object space to be sealed is almost unchangeably maintained. |
