| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a packing, keeping high sealing performance over a long period of time without causing oil leakage and poor lubrication even in the use in the high-pressure load state. <P>SOLUTION: A piston rod 3 is inserted to freely move in a cylinder 2, and the packing is housed in an annular groove 10 formed in the cylinder 2 to seal a clearance gap between the cylinder 2 and the piston rod 3 while it is brought into sliding contact with the peripheral surface of the piston rod 3. The packing is composed of a U-packing and a deformation regulating member 17, which are respectively housed in the annular groove 10. The U-packing 7 is constructed by an annular base 12 and a pair of annular lips 13, 14 raised from the base 12. The deformation regulating member is formed of thermoplastic resin having excellent rigidity, strength and creep resistance more than the U-packing 7, and the deformation regulating member is disposed in a position close to the clearance gap in the wall surface 10a of the annular groove 10 to be opposite to the heel part 11 of the base side corner of the U-packing 7. <P>COPYRIGHT: (C)2006,JPO&NCIPI |
