Cylinder or cylinder liner
AssigneeNippon Piston Ring Co., Ltd.
InventorShigeru Urano
Life of this patent
Estimating the term…
Abstract
An internal combustion engine including a piston and cylinder liner in which the cylinder liner is provided with plural annular hardened layers formed on the inner peripheral surface thereof in the vicinity of the top dead center of the piston. The distance between adjacent ones of the annular hardened layers is smaller than the axial length of a piston ring employed with the piston. The width of each of the hardened layers is in a range of from one-half to twice the axial length of the piston ring. The hardened layers may be formed by hardening with a laser beam. The piston ring can be provided with a hardened layer on its outer surface. The piston ring preferably has a barrel shape.
Claims6
An internal combustion engine comprising:
- a piston, a cylinder and a cylinder liner, said piston being operatively disposed in said cylinder, said cylinder liner having a plurality of spaced separate annular hardened layers produced directly from the cylinder liner without discontinuity, on the inner peripheral surface of said liner in the vicinity of the top dead center of said piston, the distance between adjacent annular hardened layers being smaller than an axial length of a piston ring of said piston.
Dependencies are inferred from the claim text.