Patent · US Expired

Micro drill with modified drill point

US4602900A · kind A · utility

44Cited by
18References
4Claims
0Family size

Inventors

Key dates

Filing dateSep 26, 1983
Grant dateJul 29, 1986
Priority date
Expiry dateSep 26, 2003

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10T408/9097
  • WIPO fieldMedical technology
  • WIPO sectorInstruments

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.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.