Patent · US Expired

Rotary air percussion bit

US4091884A · kind A · utility

12Cited by
7References
3Claims
0Family size

Assignee

Inventor

Key dates

Filing dateNov 15, 1976
Grant dateMay 30, 1978
Priority date
Expiry dateNov 15, 1996

Classification

  • Technology area (CPC E)Fixed Constructions
  • CPC primaryE21B10/56
  • WIPO fieldCivil engineering
  • WIPO sectorOther fields

Abstract

A rotary air percussion bit has a cylindrically shaped sidewall, a body portion with a flat or recessed face on one end and a shank attached to the remaining end. A plurality of inserts of wear resistant material is mounted in the face and extending outwardly therefrom. A plurality of chip cutting grooves is formed in the face and extending radially from the axis of the body outwardly to the sidewalls. In order to improve the chip removal from the bit a plurality of chip clearance grooves is formed in the sidewall of the body extending from the terminus of the face chip cutting grooves and spiraling from the face to the shank end. The angle of the spiral with respect to the face is less than 45.degree..

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