Apparatus for drilling holes in mine roofs and a roof drill bit for use therein
US5301763A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 2, 1993 |
| Grant date | Apr 12, 1994 |
| Priority date | — |
| Expiry date | Mar 2, 2013 |
Classification
- Technology area (CPC E)Fixed Constructions
- CPC primaryE21B10/54
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
A roof drill bit for drilling a bolt hole in a mine roof comprises a body defining a longitudinal axis of rotation and having an external periphery and a front face. A longitudinal fluid channel is formed in the external periphery for conducting a flow of flushing fluid to the front face. An imaginary longitudinal plane which contains the axis of rotation serves to bisect the front face into first and second sides. A cutting edge arrangement is defined by at least one cutting insert mounted on the body. The insert is positioned to be acted upon by the flow of flushing fluid. At least one support pad is mounted on the external periphery for balancing cutting forces acting on the drill bit. The cutting arrangement is asymmetrical with respect to the axis of rotation such that the cutting edge arrangement is disposed on one of the sides, and the other side is substantially free of the cutting edge arrangement.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.