| 摘要 |
<P>PROBLEM TO BE SOLVED: To impart to a combined oil control ring a function for preventing independent rotation of a side rail, to maintain the function over a long term, to provide a counter measure for fretting fatigue and to provide a combined oil control ring with which the independent rotation of the side rail can be prevented in a low-tension combination oil control ring. <P>SOLUTION: The oil control ring includes upper and lower two side rails and an spacer expander interposed therebetween and including a flange part, in an inner peripheral part, for pressing inner peripheral surfaces of the side rails. In the combination oil ring, recesses and protrusions extending in a substantially axial direction are included on a side rail pressing surface of the flange part, and convex surfaces of the recesses and the protrusions include angular parts. <P>COPYRIGHT: (C)2013,JPO&INPIT |
