Method and apparatus for changing bits while drilling with a flexible shaft
US5746279A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Feb 20, 1996 |
| Grant date | May 5, 1998 |
| Priority date | — |
| Expiry date | Feb 20, 2016 |
Classification
- Technology area (CPC E)Fixed Constructions
- CPC primaryE21B19/18
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
An apparatus and method are disclosed for the removal and replacement of the used drill bit after each perforation through casing, cement, and into rock while using a flexible drive shaft. This apparatus involves both a bayonet-style "quick connector" between the flexible shaft and the drill bit and a cartridge that holds the drill bits while they await their turn to be used. The apparatus also has a means for indexing the cartridge so that the flexible shaft can have access to each of the drill bits in the cartridge. The method disclosed involves the process of connecting the flexible shaft to the drill bit at the start of the perforating process, the disconnecting of the used bit at the end of the perforation, and the indexing of the cartridge so that the next drill bit is in line with the flexible shaft for the next perforation.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.