Internal combustion engine

摘要

An internal combustion engine comprises a cylinder, a piston reciprocating in the cylinder, piston rings arranged on the periphery of the piston, and at least a pair of oil ports symmetrically provided in a wall member of the cylinder. The oil ports communicate with the space between the wall member and the piston and are positioned to open onto the portion below the lowermost piston ring during the reciprocation of the piston. A system supplies a portion of the lubricating oil for the internal combustion engine under pressure to this space through the oil ports, and conduits communicate the oil ports with the supply system.