| 摘要 |
PROBLEM TO BE SOLVED: To provide a combination oil control ring for an automobile engine in which an excellent oil control function can be maintained without fixing a spacer expander and a side rail even in a long-term engine operation.SOLUTION: A combination oil control ring includes two upper and lower side rails, and a spacer expander in which crests and troughs are formed in an axial waveform. The crest and the trough of the spacer expander are constituted by a flange pressing an inner peripheral surface of the side rail, a protrusion supporting the side rail, and an intermediate portion between the flange and the protrusion. The intermediate portion confronting the side rail has a projection, and the projection projects in an almost circumferential direction, and projects in a radial direction.SELECTED DRAWING: Figure 1(a) |
