| 摘要 |
<P>PROBLEM TO BE SOLVED: To suppress occurrence of the separation of a seal in a valve stem seal including an oil lip and a back pressure lip and fitted to the outer-diameter portion of a valve stem guide. <P>SOLUTION: A pressure receiving lip engaging with a guide groove of the valve stem guide is provided in an inner-diameter surface of an inner-diameter rubber portion, and a channel is provided in a portion located between a back pressure lip and the pressure receiving lip of the inner-diameter rubber portion so as to guide pressure which has entered from a gap between the valve stem guide and a valve stem to a space between the valve stem guide and the back pressure lip, toward the pressure receiving lip, thereby canceling part of the pressure. <P>COPYRIGHT: (C)2011,JPO&INPIT |
