Rock drilling tool, drill bit and a method of transferring percussive energy
US5984030A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Sep 11, 1997 |
| Grant date | Nov 16, 1999 |
| Priority date | — |
| Expiry date | Sep 11, 2017 |
Classification
- Technology area (CPC E)Fixed Constructions
- CPC primaryE21B17/0426
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
A rock drilling tool for percussive drilling includes a drill bit and a drill tube cooperating by means of shoulder abutment in a threaded connection. The connection includes at least one male thread and a female thread. The male thread is provided on a shank being an integral part of the drill bit. The drill bit is provided with a shoulder at the inner end of the shank, the shoulder having an abutment surface facing towards the free end of the shank. The female thread is provided in the drill tube and the free end of the drill tube is provided with an impact surface. The threads are cylindrical. The combination of shoulder abutment with a short head provides straight energy transfer at a rock drilling tool.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.