FIELD: mining industry; applicable in stoping of bedded coal deposits with use of complexes with powered hydraulic support. SUBSTANCE: mechanism includes roofing of support unit, extensible side member with vertical sheet and horizontal sheet located below surface of roof under protruding as cantilever upper horizontal sheet of roofing, guide members and ram which is located with open access from support. Guide members are made in the form of two levers turning in horizontal plane and connected to form parallelogram with two vertical pins on roofing displaced to face and two vertical pins on vertical sheet of side member displaced to caving side. Ram is located inside parallelogram and connected with its caving end, with vertical pin to roofing and with face end, with vertical pin to vertical sheet of side member. Ram may be made of springs. EFFECT: increased safety of support and facilitated mounting operations. 2 cl, 3 dwg
