PISTON RING STRUCTURE

摘要

PROBLEM TO BE SOLVED: To provide technique capable of restraining friction and slapping sound from occurring while restraining problem such as seizure of a piston and deterioration of fuel consumption from occurring in a piston ring structure provided on the piston which reciprocates in a cylinder. SOLUTION: The structure is provided with a ball 11 which is plurally disposed within an oil ring groove 3a in circumferential direction and comes into contact with inner peripheral surface 101a of a cylinder bore and a back-up ring 12 which is provided on inside diameter side rather than the ball 11 and urges the ball 11 in outside diameter direction. COPYRIGHT: (C)2006,JPO&NCIPI