Patent · US Expired

Underreamer with cylindrical boss and socket hinge assembly for the cutter arm

US4461361A · kind A · utility

9Cited by
9References
6Claims
0Family size

Assignee

Inventor

Key dates

Filing dateDec 7, 1981
Grant dateJul 24, 1984
Priority date
Expiry dateDec 7, 2001

Classification

  • Technology area (CPC E)Fixed Constructions
  • CPC primaryE21B10/345
  • WIPO fieldCivil engineering
  • WIPO sectorOther fields

Abstract

An underreamer having a plurality of drilling arms hingedly attached to a tubular body for movement between a retracted position and an extended position for drilling. The hinge attachment includes a cylindrical boss and socket assembly, between the arm and a removeable hinge plate retained in a recess in the body against outward movement by an engaging key and keyway between the plate and wall of the recess.

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