| 摘要 |
PURPOSE:To prevent any fatigue failure from occurring as well as to prolong the extent of service life for each ring, pressing both backup and seal rings by forming a first ring into a sectional wedge form, and holding the leg part of a second ring between this first ring and two backup rings. CONSTITUTION:A first ring 10 is formed into a sectional wedge form, and two legs 20, 21 of a second ring 13 are held between this first ring 10 and two backup ring parts 11, 12. When pressure oil has flowed into a device at time of pressure load, a high pressure side control part 20 of the second ring 13 presses the first ring 10, trying to deform and shift it toward the low pressure side. Therefore, a low pressure side outer circumferential surface of the first ring 10 presses the low pressure side leg part 21 of the second ring 13 toward the outer circumferential side, so that the low pressure side 21 of the second ring 13 presses the backup ring 12 as well. Accordingly, the second ring 13 is not locally deformed so largely, therefore even if high pressure is repeatedly loaded at both sides of a sealing device 3, a fatigue failure will in no case occur in the device. |
