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. 24, 2007
Filed:
Apr. 08, 2004
Applicants:
Heinrich Friederich, Gross-Rohrheim, DE;
Christof Homrighausen, Bad Berleburg, DE;
Inventors:
Heinrich Friederich, Gross-Rohrheim, DE;
Christof Homrighausen, Bad Berleburg, DE;
Assignee:
EJOT GmbH & Co. KG, , DE;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
B21H 3/02 (2006.01);
U.S. Cl.
CPC ...
Abstract
In a process for the production of a screw comprising a low-alloy carbon steel, having a head, an adjoining holding portion and a functional tip which, in the outer region of limited radial depth, is of a greater hardness than the holding portion, in which the screw body is shaped by pressing and rolling and then the functional tip is subjected to a hardening operation, hardening is effected by momentary heating with a high level of energy transfer and subsequent quenching and is limited to portions of the periphery of the functional tip.