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. 17, 1991
Filed:
May. 31, 1989
Siegfried Bohnet, Mossingen, DE;
Werner Grafe, Reutlingen, DE;
Cubic Defense Systems Inc., San Diego, CA (US);
Abstract
To permit boring with replaceable cutter elements (10, 10a, 10b), particularly into materials where, upon withdrawal of the boring tool from a bore hole (40), grooves or scratches are to be avoided, two cutter elements are positioned on a fluted cylindrical body (1), the cutter elements being so located that the inner cutter element (10b) is positioned on the body so that an effective cutting edge (19) thereof is radially inwardly of the theoretical circle (33) formed by the outer cutter element (10a) upon rotation of the tool, the cutting corner of each cutter element is formed as a relieved or chamfered corner (15) and forms a chopped corner cutting edge (22). Both cutter elements (10a, 10b) are so positioned on the body that the chopped corner cutting edges are located at least in part on a diametrical plane (34) passing through the axis of rotation (31) of the body, and the inner cutter element, additionally, is so located that its chopped corner cutting edge (22 ) is located in the immediate vicinity of, at, or intersects the axis of rotation (31) of the body. The outer cutter element is so positioned that a corner cutting edge portion (23) projects beyond the circumference of the boring tool and it is oriented such that the main cutting edge portion (19) thereof extends along a chord with respect to the theoretical circle (33).