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:
Apr. 10, 2001
Filed:
Apr. 21, 1999
Applicant:
Inventors:
Assignee:
Showa Aluminum Corporation, Osaka, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
B23K 2/004 ;
U.S. Cl.
CPC ...
B23K 2/004 ;
Abstract
An entry board for drilling small holes having a front surface layer made of aluminum or aluminum alloy to be disposed at the drilling inlet side and a back surface layer made of aluminum or aluminum alloy to be disposed at the drilling outlet side. The back surface layer is adhered or joined by clad rolling to said front surface layer. The hardness of the front surface layer is smaller than that of the back surface layer.