Patent · US Expired

In-the-hole drill

US4637475A · kind A · utility

26Cited by
15References
10Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJan 23, 1984
Grant dateJan 20, 1987
Priority date—
Expiry dateJan 23, 2004

Classification

  • Technology area (CPC E)Fixed Constructions
  • CPC primaryE21B7/024
  • WIPO fieldCivil engineering
  • WIPO sectorOther fields

Abstract

A compact, easily disassembled, minimum headroom drilling unit is disclosed. The drill, especially useful for newly developed vertical retreat mining methods, drills at compound angles from the vertical and horizontal directions. Low headroom is achieved by the employment of a double acting hydraulic cylinder.

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