Patent · US Expired

Core bit having axial conical core breaker

US4207954A · kind A · utility

23Cited by
9References
9Claims
0Family size

Assignee

Inventor

Key dates

Filing dateMar 31, 1978
Grant dateJun 17, 1980
Priority date
Expiry dateMar 31, 1998

Classification

  • Technology area (CPC E)Fixed Constructions
  • CPC primaryE21B10/46
  • WIPO fieldCivil engineering
  • WIPO sectorOther fields

Abstract

A drilling tool comprising a body having a leading face with a central recess providing the body with an annular leading cutting edge such that during drilling a central core is formed, and a central cone positioned axially in the recess for breaking up the core.

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