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:
May. 15, 1990
Filed:
Dec. 20, 1988
Hisanobu Kanamaru, Hitachi, JP;
Susumu Aoyama, Misato, JP;
Tsutomu Koike, Misato, JP;
Naotatsu Asahi, Matsudo, JP;
Yoshiki Hirai, Matsudo, JP;
M. H. Center Limited, Saitama, JP;
Hitachi Powdered Metals Co., Ltd., Chiba, JP;
Abstract
The present invention is to extrude helical internal gears and helical gears by pushing materials processed to any type of blank into a die unit successively by use of a punch, i.e., by passing the materials once through the die unit. The invention is directed to a die unit comprising an outer contour restraining container into which metal material blanks each having a central bore are to be inserted, a die placed contiguously below the container, these container and die being arranged to be circumferentially rotatable relative to each other, and upper and lower mandrels disposed inside the container and the die in alignment with their axes, respectively, and interconnected for being circumferentially rotatable relative to each other, the metal materials being successively pushed into gaps between the upper mandrel and the container and between the lower mandrel and the die by means of a punch to mold helical internal gears.