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. 29, 1986
Filed:
Sep. 26, 1983
Jerry Arpaio, Jr, Johnson City, TN (US);
Derek E Heath, Johnson City, TN (US);
Other;
Abstract
The specification discloses a micro drill with a modified point in which the drill is formed from a rigid cylinder and has two opposed helical wings and helical edges. Each wing has an undercut leading surface to provide a positive rake angle at the helical edges of the wings, and the two wings have a smooth 'S' shaped cross-section. Two opposed flanks are formed by an inclined cut in each of the wings providing the drill point with a somewhat V-shape, and a leading corner is defined on each of the wings at the intersection of the helical edge and the flanks. A cut is provided in each of the leading surfaces adjacent to and below the flanks thereby forming a cutting edge on the drill point with an increased positive cutting action. The drill may be cut so that an under-surface is formed immediately below each flank and its cutting edge and so that a side surface is formed in the wings in an orientation perpendicular to the under-surface.