| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an oil seal for reciprocating which can surely guarantee high performance by preventing an inner periphery of backup ring from totally contacting with reciprocating shaft. <P>SOLUTION: An oil seal 1 for reciprocating comprises: a seal body 6 equipped with a seal lip 7 capable of being processed in slide-contact with a reciprocating shaft 8; a backup ring 4 which is arranged so that it may support the seal lip 7 from atmospheric air side for keeping a pressure resistance ability of the seal lip 7, and formed by a resin in which at least one annular groove 21 capable of supporting a lubricating member is arranged in an inner periphery facing the reciprocating shaft 8; and a supporting member 22 supporting the backup ring 4 in such a manner of sandwiching at a space with the seal body 6. Furthermore, an inner periphery 20 of the backup ring 4 is formed so that it is tapered to increase the diameter from a sealing side OS to an atmosphere side AS along axial direction. <P>COPYRIGHT: (C)2008,JPO&INPIT |
