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:
Mar. 27, 2001
Filed:
Jul. 09, 1999
Applicant:
Inventors:
Hiroshi Yamagata, Iwata, JP;
Toshikatsu Koike, Iwata, JP;
Assignee:
Yamaha Hatsudoki Kabushiki Kaisha, Iwata, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
B21J 1/302 ;
U.S. Cl.
CPC ...
B21J 1/302 ;
Abstract
An improved method of forging a piston and a forging die therefor. The forging die is formed from a pair of pieces which form an area where the forged material is extruded into. These pieces merge at a parting line that passes through the center of the outer edge of the forged material so as to afford some relative movement between the die pieces to avoid cracking and also to permit air to escape. Some small flash or parting line may be present in the finished material which is not objectionable and permits the attainment of the higher strength and better wear resistant piston.