Drilling tool and method of using same
US6488103B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Jan 3, 2001 |
| Grant date | Dec 3, 2002 |
| Priority date | — |
| Expiry date | Jan 3, 2021 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF16C2352/00
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
A drilling tool having a pilot bit on an end of a main shaft is surrounded by outer shafts having mills on their ends. The bit and mills employ cutters with PDC. The pilot bit rotates in a direction opposite the direction of rotation of the mills. A transmission for rotating a main shaft, on which the pilot bit is mounted, and several secondary shafts, on which the mills are respectively mounted, is carried within a housing using diamond thrust and radial bearings. Power is applied to the main shaft and transmitted to the secondary shafts through diamond hardened gears. Drilling fluid is used to cool and lubricate the bearings and gears.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.