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. 18, 1999
Filed:
Jul. 24, 1997
Applicant:
Inventor:
Arno Friedrichs, Hamburg, DE;
Assignees:
Konrad Friedrichs KG, Kulmbach, DE;
Guehring oHG, Albstadt, DE;
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
B29C / ;
U.S. Cl.
CPC ...
425381 ; 72264 ; 76-51 ; 761086 ; 2642092 ; 408 59 ; 4253823 ; 425461 ;
Abstract
An apparatus for manufacturing a rod of hard metal or ceramic with at least one helical inner bore. A plasticized mass of hard metal or ceramic is simultaneously forced through a die and twisted. Either the mass is twisted uniformly over the cross-section of the billet by a spinner immersed in the mass or the spinner is rotated by the mass. The mass emerges either subject to torsion or entirely or mostly without torsion from a smooth downstream channel through the die. A filament-shaped material extends or is injected into the mass to produce the inner bore or bores.