MINE SUPPORT PROP Russian patent published in 1998 - IPC

FIELD: mine supports. SUBSTANCE: prop has sleeve with recess in lower part accommodating prop and yielding insert arranged above each other. Located in sleeve, on its base, under yielding insert is retractable insert with holder. Holder is installed in sleeve recess. Sleeve base perimeter may be made larger than sleeve perimeter. Sleeve base may have guides installed on the sides from sleeve recess at distance ensuring free motion of retractable insert between them. Sleeve base may have stops for limiting motion of movable insert. EFFECT: higher efficiency. 4 cl, 3 dwg