INTERNAL COMBUSTION ENGINE Russian patent published in 1996 - IPC

FIELD: mechanical engineering. SUBSTANCE: engine has cylinder liner 1 with working surface 2 and piston 3 mounted in sleeve. Piston has crown and lateral surface including flame belt 10, area of grooves 11, 12 and 13 for piston rings and guide belt 14. Appplied to flame belt 10 and guide belt 14 of piston is antifriction coating in form of sections 15 and 16 between which section 17 is located. Section 17 is section of piston lateral surface with no coating. Height h₁ of section 15 of coating on flame belt from piston crown is 0.3 to 0.4 of height of this belt and height h₂ of section 16 of coating on guide belt 14 from its lower edge is 0.2 to 0.4 of height of this belt. Antifriction coating 19 may be applied on working surface 2 of liner 1. Sections of coatings on flame and guide belts of piston which are located at maximum distance over its lateral surface provide fro accurate basing and high stability of piston during its motion in cylinder along working surface of liner, as well as for elimination of cocking, knocking and excessive wear. Besides that, temperature and thermal stress of piston and sleeve are equalized in height. EFFECT: enhanced efficiency. 3 cl, 3 dwg