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. 22, 2008
Filed:
Aug. 30, 2005
Tatsuya Okui, Osaka, JP;
Koichi Kuroda, Osaka, JP;
Masayoshi Akiyama, Osaka, JP;
Sumitomo Metal Industries, Ltd., Osaka, JP;
Abstract
A die through hole has an inside surface including a bell portion, an approach portion, and a bearing portion from the entrance side. The diameter of the approach portion is Don its entrance side and Don its exit side and gradually decreases from the entrance side to the exit side. The diameter satisfies Equation (1): 0.7≦D/D<0.97. The die half angle of an inside surface where the diameter Dis D/0.97 is not less than the die half angle Rof an inside surface nearer to the approach portion exit side than the inside surface where the diameter is D. The axial distance LR from the inside surface where the diameter is Dto the inside surface where the diameter is Dsatisfies Equation (2): 20≦LR/((D−D)/2)≦115. The through hole diameter at the bearing portion is fixed at D, and the length is LB and satisfies Equation (3): 0.3≦LB/D≦10.