ROOFING OF POWERED SUPPORT UNIT Russian patent published in 1995 - IPC

FIELD: underground coal mining. SUBSTANCE: roofing of powered support unit has capping 1 and canopy 2, removable bar 9 and hydraulic cartridge 12. Bar 9 has curved projections 5 interacting with curved recesses 3 on guides 8 of capping 1. Hydraulic cartridge 12 is installed on roofing for interaction with end of bar 9. Bar 9 has two supporting surfaces, one of them (surface a) carries canopy 2, and the other (surface b) carries hydraulic cartridge 12. Bar 9 is connected to ears 11 by means of pins 10. External load on canopy 2 is taken up by contacting surfaces 6 and 7 of bar 9 and hydraulic cartridge 12. When canopy 2 turns round center 0 of hinge joint, contacting surfaces 6 and 7 slide over curved sliding surfaces 4 of curved recesses 3. Canopy 2 is mounted after bar 9 is brought to its place and subsequent hanging of canopy 2. EFFECT: higher efficiency. 3 dwg