Piston ring assembly
OwnerKazutoshi Takashimainventor
Life of this patent
Estimating the term…
Abstract
A piston and piston ring assembly has a compression ring and a lubrication control ring. The compression ring substantially seals a combustion chamber from a crankcase chamber. The lubrication control ring is configured with a reverse-taper end surface and a wiping edge. The reverse-taper end surface allows the lubrication control ring to leave a thin lubricant coat on a cylinder wall during a piston downstroke. The wiping edge pulls lubricant upward toward the compression ring during a piston upstroke. The combination of the elements and the elements on their own result in enhanced lubrication of the compression ring and thereby increase the life of the piston ring and reduce the wear on the ring and the cylinder bore.
Claims14
A piston and piston ring assembly for a direct injection internal combustion engine, the piston comprising a head, at least two circumferential ring grooves positioned proximate the head, a compression ring positioned within the top ring groove and a second ring positioned within the second ring groove, the second ring having a top surface and a bottom surface wherein the top surface has a greater outside diameter than the bottom surface, a reverse-taper side surface extending between the outside edge of the top surface and the bottom surface, the upper end of the reverse-taper side surface forming a wiping edge of the second ring.
A piston and piston ring assembly for use within a cylinder of an internal combustion engine, the piston and piston ring assembly comprising a piston having a piston ring groove and a head, the piston ring groove having a width at its inner diameter, a piston ring positioned in the piston ring groove, the piston ring having a top surface generally facing toward the piston head and a thickness at its innermost edge, the top surface extending outward to a wiping edge, a face depending downward from the wiping edge and extending inward toward the piston, the piston ring thickness being less than the piston ring groove width and the wiping edge arranged to wipe a portion of a lubricant film from a cylinder wall.
Dependencies are inferred from the claim text.