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:
Aug. 08, 2000
Filed:
Jul. 13, 1998
Applicant:
Inventors:
Assignee:
Daido Tokushuko Kabushiki Kaisha, Aichiprefecture, JP;
Primary Examiner:
Int. Cl.
CPC ...
C21D / ;
U.S. Cl.
CPC ...
148607 ; 148608 ;
Abstract
A method for producing an exhaust valve is described, comprising subjecting a raw material of a specified heat resisting alloy to solid solution treatment; forming a head portion of the exhaust valve from the solution treated raw material through cold working or warm working; joining a stem portion made of martensitic heat resisting steel to said head portion of the exhaust valve; and subjecting the head portion and the stem portion joined with each other to aging treatment.