Patent · US Expired

Deck-mounted shaft bushing

US4186973A · kind A · utility

3Cited by
3References
18Claims
0Family size

Assignee

Inventor

Key dates

Filing dateJul 25, 1978
Grant dateFeb 5, 1980
Priority date
Expiry dateJul 25, 1998

Classification

  • Technology area (CPC E)Fixed Constructions
  • CPC primaryE21B19/24
  • WIPO fieldCivil engineering
  • WIPO sectorOther fields

Abstract

A guide bushing mountable in a supporting sleeve in the deck of a blast hole drill for guiding a drill string extending through the sleeve, the bushing having a tubular core providing a cylindrical axial bore adapted to receive and guide the drill string, the core having a flange by which it is supported in the supporting sleeve, and in which a resilient, elastomeric cushion mounted on the exterior of the core serves to cushion transverse movements of the bushing within the supporting sleeve. Preferably, the bushing is formed of two halves fastened together by hinges, so that it can be opened and laterally installed around the drill string.

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