| 摘要 |
A lip seal comprises resilient annular sealing means 2, 3, having a sealing lip 4 adapted for sealing engagement at an end 9 thereof with a relatively movable shaft 5 and a valve lip 6, the lips being, in use, normally closed, and means 11, 13, for injecting fluid into a space 7 between the closed lips 4, 6 at sufficient pressure to cause the lips to open during use to allow the fluid to flow towards the end 9 of the sealing lip 4. <IMAGE> |
