Abstract: The invention refers to a device with which provisional consolidating frames adapted to be brought to a smaller size can be transported to the drift face and can be put in place. According to the invention this device is arranged on the cutting machine itself so that the narrow space remaining between the contour of the cutting machine and the cross section of the drift is sufficient for transporting in forward direction and putting in place the provisional consolidating frames without the necessity to retract the face advancement machine from the drift face. Thus, face advancement machines can be used which occupy the major part of the inside width of the drift, noting that the face advancing machine is maintained in its working position. The invention further describes a doorjamb frame for the provisional drift consolidation and which is particularly suitable for the device proposed.

Abstract: An arrangement for tensioning a gateway conveyor in a sloping gateway during longwall working using supports having base frames which are provided with pulling and shifting hydraulic actuators, wherein in a tensioning device is provided at least at one of the supports and is connected at one end to the gateway conveyor and at the other end to a slide member which is slidably guided by the base frame of the support for a movement which is transverse to the longitudinal direction of the gateway conveyor, characterized in that the slide member which is slidably guided for a movement which is transverse to the longitudinal direction of the gateway conveyor consists of a guide frame, which is supported by the base frame against forces acting in the longitudinal direction of the gateway conveyor, the cylinder of the pulling and shifting actuator is axially immovably mounted in the base frame and its piston is connected to said guide frame, which when retracted extends on opposite sides of the pulling and shifting a

Abstract: A cutting machine having a universally movable cutting arm provided with a plurality of cutting heads in which the cutting machine's oil reservoir is mounted within the cutting arm and cooled by the water cooling system for the cutting machine's motor. The cutting heads and the reduction gearing drive therefor employ a common reservoir which is connected to and supplied by the cutting machine's main oil reservoir so that the cutting heads and associated drive gearing are continuously being supplied with cooled oil and are themselves cooled thereby.

Abstract: A device for separating dust particles from an air stream, in particular for mine ventilation, comprising a centrifugal separator, a blower for conveying the air stream through the centrifugal separator, and a device connected in advance of the centrifugal separator in the air flow direction to spray or atomize water which is fed into the air stream entering the centrifugal separator, the centrifugal separator being formed from at least one impeller with substantially radial blades connected together at their outer ends by circumferentially extending walls, the distance of which from the axis increases in the air flow direction, passage apertures being provided to the housing at the positions of greatest diameter.