Abstract: A mobile mine roof support assembly has three mine roof support units coupled together by a common transverse beam. Roller devices are mounted beneath the floor sills of the support units. The roller devices are spring biased away from their floor sills so that they can lift the floor sills away from the floor of a working when the assembly is to be moved. At least one roller device of each support unit is a steerable roller device so that the assembly can be steered round bends. Each steerable roller device is pivotally mounted on its floor sill about a vertical axis, and is provided with an associated steering device. The steerable roller devices are preferably coupled together by means of a common steering device.

Abstract: A mine roof support has a main roof bar which is pivotably connected to an auxiliary forwardly-extendible bar. A piston and cylinder unit serves to swing the auxiliary bar about the main bar to bring the auxiliary bar into a roof-contacting position aligned with the main bar or into a stowed position beneath the main bar or into some intermediate position. Pivotable guide members connect between the main and auxiliary bars respectively and a pivot joint linked to the piston and cylinder unit. The guide members can take the form of simple straps or levers but an additional piston and cylinder unit can also be used as one of the guide members.

Abstract: A shield-type support assembly for a mine working is composed of three substantially identical frames aligned side-by-side. Each frame has a floor sill structure which carries props capable of bracing a roof cap and the floor sill structure between the roof and floor of a mine working. A goaf shield is provided for each frame and these shields combine to screen off the goaf zone. The outer frames on the one hand and the central frame on the other are shiftable in alternation with the aid of shifting rams. One or more transverse arms extend across the forward regions of the frames and the or each arm is carried by the central frame floor sill structure. Guide devices are connected to the arm or arms and serve to guide the frames when shifted by the rams and the rams themselves transmit the shifting or reaction forces to the arm or arms.The coupling between the floor sill structures of the frames permits relative vertical mobility therebetween to cope with variations in the floor level of the working.

Abstract: 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.