SUPPORT ASSEMBLIES FOR USE IN MINE WORKINGS

摘要

A mine support assembly is composed of separate floor-engaging sills each supporting one or more telescopic props and a goaf shield pivotably connected to a roof cap. The props can be extended or retracted to raise or lower the roof cap. The shield is divided into a common upper section and lower parts each pivotably connected to the upper section and to a respective associated one of the floor sills. Levers are pivotably connected between the sills and the upper section of the goaf shield and serve with the lower shield parts as a guide means ensuring the roof cap is raised or lowered without appreciable horizontal displacement. The floor sills and lower shield parts are respectively spaced apart and a shifting ram is connected to the floor sills via a transverse yoke pivotably connected to the forward end regions of the sills. The ram is located in a space between the sills and is connected at its rear end to a cross piece guided in the sills and connected to bars which extend along the space between the sills to form a cantilever beam connected directly or indirectly to a longwall conveyor.