Combined resin-mechanical mine roof bolt anchor
US4664561A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Aug 12, 1986 |
| Grant date | May 12, 1987 |
| Priority date | — |
| Expiry date | Aug 12, 2006 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF16B2013/148
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
A system is disclosed for anchoring a tensioned bolt in a drill hole in the roof of a mine, or other such location. The bolt is threaded from one end and has a head on the other end which carries a standard bearing plate. The bolt passes through a hollow tube having an outer diameter slightly (e.g., 1/8") smaller than the bore hole diameter. The threaded end of the bolt engages a nut affixed to the upper end of the tube and extends through the nut to the end of the threads. A standard, mechanical, expansion anchor is carried on the threaded end of the bolt extending through the tube and is inserted into the drill hole behind a conventional, two-compartment resin package. As the bolt is pushed into the hole, the package is broken and the resin components are forced into the annular space around the hollow tube, as well as around the threaded end of the bolt and expansion shell. Rotation of the bolt to expand the anchor also rotates the hollow tube, mixing the resin components and forcing the mixture into voids in the wall of the drill hole. The hollow tube is tapered inwardly toward its lower end providing a wedge effect resisting downward movement in the drill hole.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.