Mine roof supports
US4784532A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jun 19, 1987 |
| Grant date | Nov 15, 1988 |
| Priority date | — |
| Expiry date | Jun 19, 2007 |
Classification
- Technology area (CPC E)Fixed Constructions
- CPC primaryE21D23/06
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
A roof engaging structure for a mine roof support comprises at least two relatively movable roof engaging members 21 and 23, which are coupled together by at least two spaced-apart pivotal joints 25 and 26. The pivotal joints combine to influence the relationship of the roof engaging surfaces of the two members. In one embodiment for example, the roof engaging surfaces of the two roof engaging members may adopt either an angular or a parallel relationship with respect to one another, one surface lying at least partially below the adjacent surface. The arrangement enables the roof engaging structure to shape itself to various forms of mine roof, while preventing jack knifing of the forward end of the roof engaging structure.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.