SIDE RAIL AND COMBINED OIL CONTROL RING INCORPORATED WITH THE SIDE RAILS FOR REDUCTION OF OIL CONSUMPTION

摘要

A side rail is formed into a ring shape having its generally rectangular section that has an outer surface 3 formed with a pair of edge surfaces 5 of small radius, and an intermediate surface 6 of large radius of curvature formed between the edge surfaces 5 . When the side rail is in the inclined condition in operation, each edge surface 5 can easily ride on oil film on cylinder 16 and allow the side rail 1 to perform smooth sliding movement on the inner surface of cylinder. The intermediate surface 6 efficiently scrapes lubricating oil on cylinder to form lubricating oil film of necessary and minimum thickness between an inner surface 17 of cylinder 16 and side rail 1 . Also, the larger radius of curvature for forming the intermediate surface 6 provides a larger contact area to the inner surface 17 of cylinder 16 to improve wear resistance.