| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an oil seal arranged in an annular space of which rotary shaft rotates in both directions and having screw groove provided on an atmospheric air side inclined surface of a lip part, not leaking oil from the screw groove provided to have a pump function at a time of reverse rotation in a high speed rotation zone and securing sealing nature by the screw groove. <P>SOLUTION: In the oil seal to make sliding contact with the rotary shaft at a sliding contact section of the lip part 51, a gap 54 is formed between a tip 61 of the screw groove 6 and a lip edge 53 of the lip part 51, the screw grove 6 does not make sliding contact with the rotary shaft but demonstrates screw effect when a sliding contact section 55 makes sliding contact with the rotary shaft over whole circumference at an early stage of wear. <P>COPYRIGHT: (C)2006,JPO&NCIPI |
