摘要 |
A mobile mine-roof support comprises a powered track-laying carriage having a carrier shaft extending longitudinally of the carriage between its tracks, the end portions of the carrier shaft being arranged to support mountings of bracket form for props supporting a roof beam which is stabilized by a lemniscate guide linkage the floorward links of which ar articulated to an attachment part or extension of one of the prop mountings, with stabilization of the laterally-pivotable props being effected by an orienting cylinder supported on the chassis. |