Mine roof support unit
US4600340A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Dec 31, 1984 |
| Grant date | Jul 15, 1986 |
| Priority date | — |
| Expiry date | Dec 31, 2004 |
Classification
- Technology area (CPC E)Fixed Constructions
- CPC primaryE21D23/04
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
A mine roof support unit includes a pair of generally parallel floor girders, and an advance mechanism positioned between the floor girders. The advance mechanism comprises a hydraulic advance ram and a guide rod system. The advance ram is pivotally connected between the guide rod system and a cross member which interconnects the floor girders. The guide rod system is attachable to a longwall conveyor positioned adjacent to a work face. The cross member is engageable with the floor girders in such a manner that the floor girders are relatively displaceable in a vertical direction. Each of the floor girders is provided with a respective hydraulic lifting ram, the arrangement being such that the lifting rams can be operated to lift one of the floor girders relative to the other floor girder.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.