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:
Sep. 25, 1984
Filed:
Apr. 20, 1983
Kazuhiko Nakamura, Chiba, JP;
Takeo Nakagawa, Kanagawa, JP;
Amino Iron Works Co., Ltd., Shizuoka, JP;
Abstract
A punch is pressed on a blankpiece into a die. The die is filled with liquid therein, whereby hydraulic counterpressure is generated by said pressing. The pressed blankpiece is forcibly followed in shape around the punch by hydraulic counterpressure, while part of the hydraulic counterpressure is automatically supplied to an outer circumference of the blankpiece via bypath passage. In case, the blankpiece is a plate, said supplied hydraulic pressure serves as compression force from the outer circumference of the flange to the radius direction. In case, the blankpiece is a product formed by a first drawing, said pressure serves as pressing force toward axial direction of a side wall of the product. When the supplied hydraulic pressure flows out from a space between the punch and a blank holder, the liquid serves as lubrication on an upper and lower surfaces of the blankpiece.