Patent · US Expired

Rotary drill bits

US4804049A · kind A · utility

43Cited by
4References
8Claims
0Family size

Assignee

Inventor

Key dates

Filing dateNov 30, 1984
Grant dateFeb 14, 1989
Priority date
Expiry dateNov 30, 2004

Classification

  • Technology area (CPC B)Performing Operations; Transporting
  • CPC primaryB22F7/06
  • WIPO fieldMaterials, metallurgy
  • WIPO sectorChemistry

Abstract

The body of a rotary drill bit is formed from a matrix formed by a powder metallurgy process, and a plurality of cutting elements are mounted on the bit body, each cutting element being in the form of a disc of superhard material which is thermally stable at the temperature of formation of the matrix. The front surface of each cutting element is engaged by a holding structure on the bit body in front of the cutting element, the arrangement of the holding structure being such that the resistance provided by the holding structure to forward deflection of the portion of the cutting element opposite the cutting edge is less than the resistance to rearward deflection provided by the surface behind the cutting edge. Bending stresses imparted to the cutting element by rearward deflection thereof in the vicinity of the cutting edge are thereby reduced.

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