Valve guide and process for manufacturing thereof
AssigneeHitachi Powdered Metals Co., Ltd.
InventorsKoichiro Hayashi, Katsunao Chikahata
Life of this patent
Estimating the term…
Abstract
Disclosed is a valve guide which is manufactured by a sintered alloy and used for an engine, and more particularly, to a valve guide which has high wear resistance and can prevent appearance of scuffing on a surface of a valve stem associated with the valve guide, and to a process for manufacturing the valve guide. The valve guide comprises an inner surface sliding with a valve stem, the inner surface finished by machining and exposing pores. Area-ratio of the pores with respect to the inner surface is 2.7 to 10.7%, and at least one pore having pore size of not less than 80 .mu.m exists per 1 mm.sup.2 of the inner surface.
Claims7
A valve guide manufactured by sintered alloy, said valve guide comprising an inner surface sliding with a valve stem, said inner surface finished by machining and exposing pores,
- area-ratio of the exposed pores with respect to the inner surface being 2.7 to 10.7%, and at least one pore having pore size of not less than 80 .mu.m existing per 1 mm.sup.2 of the inner surface.
Dependencies are inferred from the claim text.