Patent · US Expired

Drill screw

US4708557A · kind A · utility

8Cited by
5References
7Claims
0Family size

Assignee

Inventor

Key dates

Filing dateMay 8, 1986
Grant dateNov 24, 1987
Priority date
Expiry dateMay 8, 2006

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10T408/9097
  • WIPO fieldMechanical elements
  • WIPO sectorMechanical engineering

Abstract

There is disclosed herein a drill screw which comprises a threaded shank, a drilling portion formed at the forward end of the shank and a head formed at the rearward end of the shank and having a wrench head. The drilling portion includes a body extending axially from the shank, a drilling tip extending forwardly from the body and having a pair of diametrically opposite axially extending flutes. In this arragement, horizontal end cutting edges are provided at the forward end of the drilling tip whereas no web is provided at the forward end thereof. Inclined cutting edges are provided at opposite side edges of the drilling tip and side cutting edges are provided at opposite side edges of the body. The end cutting edges, the inclined cutting edges and the side cutting edges all lie in a diametral axial plane of the drilling portion while cooperating together to form rake faces inclined to cutting surfaces which form the bottom of the flutes.

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