Abstract: A lattice girder for support of a tunnel structure includes coupling elements arranged on ends of the lattice girder. Each coupling element has two sheet-metal strips having each an end formed with a loop. Extending between the coupling elements in a longitudinal direction of the lattice girder are two lower bars and an upper bar arranged to define corners of a triangle in cross section. A framework made of single braces connects the lower bars with the upper bar. Connectors are received in the loops of the sheet-metal strips.

Abstract: A tubbing lining for a tunnel or shaft is formed from tubbing rings having annular end surfaces, with successively tubbing rings are aligned with each other at annular end surfaces forming an annular joint. Each tubbing ring is composed of successive circumferentially arranged tubbing segments which are butt-joined. A deformable flexible element having an outer cross-sectional contour is arranged in at least one butt joint, with the cross-sectional contour parallel to the butt joint matching outer contours of the end faces such that the flexible element completely covers at least one abutting end face. The tubbing segments in conjunction with the flexible element form a prefabricated element formed of a steel reinforcing framework encased in concrete to which the flexible element is connected in a force-locked manner.

Abstract: A lattice girder for support of a tunnel structure includes coupling elements arranged on ends of the lattice girder. Each coupling element has two sheet-metal strips having each an end formed with a loop. Extending between the coupling elements in a longitudinal direction of the lattice girder are two lower bars and an upper bar arranged to define corners of a triangle in cross section. A framework made of single braces connects the lower bars with the upper bar. Connectors are received in the loops of the sheet-metal strips.

Abstract: A tubbing lining for a tunnel or shaft is formed from tubbing rings having annular end surfaces, with successively tubbing rings are aligned with each other at annular end surfaces forming an annular joint. Each tubbing ring is composed of successive circumferentially arranged tubbing segments which are butt-joined. A deformable flexible element having an outer cross-sectional contour is arranged in at least one butt joint, with the cross-sectional contour parallel to the butt joint matching outer contours of the end faces such that the flexible element completely covers at least one abutting end face. The tubbing segments in conjunction with the flexible element form a prefabricated element formed of a steel reinforcing framework encased in concrete to which the flexible element is connected in a force-locked manner.

Abstract: A hydraulic support for underground mining and tunnel construction includes an outer tube to form an upper prop and an inner tube which forms a lower prop and is received in the outer tube to define a pressure chamber. A footpiece is secured to a lower end of the inner tube. Provided on the upper end of the inner tube is a piston which is sealingly guided along the outer tube as pressure fluid is admitted into the upper prop. Disposed inside the lower prop at a location below the piston is a valve block for introducing pressure fluid into the pressure chamber, with a pressure tube connecting the valve block with the piston to thereby define a constant distance of the valve block to the footpiece.

Abstract: A truss has a pair of parallel and longitudinally extending chord rods and transverse rods interconnecting the chord rods. First and second slides each have a pair of tubes each fitting over a respective one of the chord rods and slidable longitudinally therealong and a cross member rigidly interconnecting the tubes and formed with a throughgoing hole through which passes a respective anchor member projecting from a tunnel or mine wall. The slides can be longitudinally fixed on the rods.

Abstract: A lattice girder supporting frame for tunnel lining includes upper and lower boom members arranged parallel to each other to form a triangle. Truss braces spatially connect the upper and lower boom members to each other, wherein each of the truss braces has straight brace parts angled relative to each other, and each of the straight brace parts is connected to each other at one end via a straight bridge piece. The truss braces are arranged in a symmetrical plane extending laterally from the upper boom member to an axis of the lower boom members. Cross ties extend at right angles relative to the lower boom members, for connecting the lower boom members to each other, wherein the truss braces abut the lower boom members without bending and are welded to the lower boom members.

Abstract: A drive unit for a mining machine such as a mining plow or conveyor drives a sprocket wheel of the chain thereof by an electric motor through a drive train having a turbocoupling and a transmission driven by the motor. A free-shifting clutch is provided in the case of overload to disconnect the load from the motor, the clutch reengaging upon standstill of the two clutch halves. Alternatively the turbine output of the fluid coupling is branched and is applied through one friction clutch directly to the input shaft of the transmission or through a second friction clutch to a parallel shaft connected by gearing to the transmission input shaft.

Abstract: A mining machine for excavating coal along a coal front of a seam in which a chain displaces excavating tools along an excavating stretch at a leading side across the coal face and a conveying stretch is provided rearwardly thereof, the stretch terminating in direction reversal stations with wheels at opposite ends of the stretches. A linear drive for at least one of the wheels can extend in a gallery alongside the mined cut. According to the invention, the excavating conveyer bottom is at an angular of 70.degree. to 130.degree. to the bottom of the conveying trough and the shafts of the wheels are inclined to the vertical forwardly and upwardly to include angles of 10.degree. to 45.degree..

Abstract: A mining machine especially for seam mining as in the mining of coal has a sensor for incipient sag of the plow pass of the continuously driven endless chain and a computer to which the sensor is connected and which controls the conveyor drive at the upstream end of the plow pass and the downstream end of a conveyor pass to reduce the speed of this drive until the plow pass is retensioned and any sag is accumulated at the conveyor pass. This arrangement eliminates problems with dislocation of the mining plow or of the conveyor flights as they are guided by guide devices onto the plow trough at the upstream end of the plow pass.

Abstract: A long-wall mining machine has an operating chain entraining conveyor flights or mining tools and displaceable in a trough which can be provided with rows of sensors of an inductive proximity type responding to the chain and the tools and generating measurement pulse trains which are compared with setpoint pulse trains to signal functional parameters of chain operation. The sag of the chain is determined by a row of sensors and in response to the sag a chain-tension unit can be controlled.

Abstract: An adjustable support column for use between ceiling and floor surfaces of a mine has an outer tube having an outer end braced against one of the surfaces and an inner end and an inner tube having an inner end in the outer tube at the inner end thereof and an outer end braced against the other surface. The tubes are coaxial to an upright axis and a wedge ring carried externally on the inner tube is tapered toward the outer tube and engageable in the inner end of the outer tube for resiliently resisting telescoping of the inner tube into the outer tube with a predetermined force and for permitting telescoping of the inner tube into the outer tube when the tubes are pressed axially together with a force greater than the predetermined force. Formations on the inner tube engage the ring for axially displacing the ring along the inner tube and fix the ring on the inner tube at any of a multiplicity of locations therealong.

Abstract: An adjustable column for use between ceiling and floor surfaces of a mine has an outer tube having an outer end and an inner end and an inner tube having an inner end in the outer tube at the inner end thereof and an outer end. The tubes are coaxial to an upright axis and an external screwthread on the outer-tube inner end fits with an inner screwthread on the inner-tube inner end so that the tubes can be screwed relative to each other to change the axial length of the column. One of the outer ends is operatively braced against one of the surfaces and the other outer end is spaced from the other of the surfaces. A resiliently compressible support element is braced axially between the other outer end and the other surface.

Abstract: A mine prop has a post or column formed by two telescopingly interfitted tubes, one of which has a bottleneck configuration over which the other is spread to provide a resistance to telescoping contraction. At the upper end, a nut is rotatable on the post and can advance the threaded spindle engaged therein to brace the prop between the roof and ceiling of a subterranean structure.

Abstract: A long-wall mining apparatus has a conveyor trough extending longitudinally from a turnaround adjacent a longitudinal face from which material is to be cut, a pair of longitudinally extending and generally parallel rear guide rails extending along and flanking the conveyor, a pair of longitudinally extending and generally parallel front guide rails extending along the face between the conveyor trough and the face, and a longitudinally fixed anchor bollard in the turnaround provided with upper and lower guide rails each connecting a respective one of the front guide rails to a respective one of the rear guide rails. A drive wheel in the bollard rotates about an upright axis and has an outer periphery exposed between the bollard guide rails. A chain having front and rear stretches respectively running along the guide rails is engaged in the turnaround with the periphery of the drive wheel.

Abstract: A cap shoe for connecting a mine prop to a head tree or cap in the form of a U-shaped girder whose U shanks have corrugations extending the full width thereof is engageable by complementary formations on the flanges of the cap or head tree which is received in the shoe. The latter is welded to the mine prop.

Abstract: A positioning cylinder assembly for subterranean mining applications has a rotary potentiometer connected through a friction wheel transmission with the spindle of the cylinder which is rotated when the piston is axially displaced therein. The friction wheel assembly comprises a pinion wheel connected to the spindle and a hollow wheel connected to the rotary potentiometer, that not only matches the pitch of the spindle to the rotary spring of the potentiometer but also functions as a slip clutch for zero setting of the potentionmeter and the piston.

Abstract: A mining apparatus of the type in which a mining machine excavates a mining face, especially a coal face in a subterranean mining application, and has a plurality of emitters of electromagnetic waves of different character diverging toward receivers on the individual walking props. The walking props are provided with a control unit which, in response to leading and trailing zones of the respective magnetic beams and/or an overlap region of the two beams, causes the advance of the walking prop as the mining machine travels past it to follow the excavation of the mining face.

Abstract: The noise spectrum in a mining chamber is captured by at least one microphone and is digitized and filtered to separate an operation-typical pattern from an operation atypical pattern. The operation atypical pattern is compared with reference patterns to establish the malfunction or vocal command or emergency and the apparatus is automatically operated in response thereto.

Abstract: A seam-mining apparatus has an excavating trough disposed ahead of a conveying trough and an endless chain passes over direction-change devices between these troughs. The excavating and/or conveying tools carried by the chain are articulated and formed with a head portion, an intermediate portion and an end portion. The intermediate portion is connected to the head portion and end portion by pin joints whose axes are perpendicular to the chain and to the bottom of the conveyor trough, and hinge joints whose axes are orthogonal to the axes of the pin joints. The guides for the head and end portions of the troughs extend into the direction-change regions.