The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jul. 19, 1983
Filed:
May. 19, 1980
Shigeru Urano, Omiya, JP;
Nippon Piston Ring Co., Ltd., Tokyo, JP;
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.