Mine roof supports
US4002036A · kind A · utility
2Cited by
6References
9Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | May 9, 1975 |
| Grant date | Jan 11, 1977 |
| Priority date | — |
| Expiry date | May 9, 1995 |
Classification
- Technology area (CPC E)Fixed Constructions
- CPC primaryE21D23/06
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
A mine roof support of the type having a canopy supported from a base structure by hydraulically extensible legs and a cantilever roof-engaging member pivotally attached to the forward end of the canopy, is provided with a selectively positionable laterally extending cantilever member by means of which the effective roof-engaging surface of the canopy can be extended, the lateral cantilever member being optionally provided with a forwardly projecting cantilever member by means of which the effective width of the roof-engaging member can also be extended.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.