Percussion drill bit having centrally projecting insert
US4304312A · kind A · utility
85Cited by
10References
9Claims
0Family size
Assignee
Inventor
Key dates
| Filing date | Jan 11, 1980 |
| Grant date | Dec 8, 1981 |
| Priority date | — |
| Expiry date | Jan 11, 2000 |
Classification
- Technology area (CPC E)Fixed Constructions
- CPC primaryE21B10/40
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
A percussion drill bit comprises a bit body including a shaft having a conical mounting portion to be mated with a conical mounting portion of a drill rod by means of substantially longitudinal friction forces. An annular row of circumferentially spaced button inserts extend from a front face of the body. A central button insert is disposed centrally of the other inserts and extends axially from the front face of the body beyond the other inserts to define a pilot insert. The outer inserts are inclined at an angle relative to the longitudinal axis of the body. A centrally located flushing channel is provided in the drill rod.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.