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:
Nov. 02, 1999
Filed:
Dec. 29, 1997
Hiroshi Oshige, Shimotsuga-gun, JP;
Nippon Piston Ring Co., Ltd., , JP;
Abstract
A process for manufacturing a valve seat which is made of a sintered Fe alloy and comprises a main layer of a valve seat and a contacting layer, comprises the steps of preparing either a powdery Cu or a powdery material containing Cu in a powdery Fe alloy, forming a green compact body with two green compact body layers, one of which is the main layer and the other of which is the contacting layer, and which are made of the prepared powdery Fe alloy containing Cu, sintering the green compact body. According to the present invention, the infiltration of Cu from the main layer to the contacting layer of the valve seat is not generated as the conventional sintering process for manufacturing the valve seat comprising the two layers without the independent infiltration treatment of Cu, and, therefore, the valve seat obtained of the present invention has an high abrasion resistance without decreasing of a strength of the main layer.