Abstract: An apparatus for cutting excavations having a substantially planar face comprises a cutting tool which is rotatably mounted on a jib. The jib is mounted on a mobile machine for a pivotal movement in a plane which is transverse to the heading direction and is divided into two jib sections which are pivotally movable relative to each other about an axis which is substantially parallel to the pivotal axis of the jib. The cutting tool is rotatably mounted close to or at the free end of that jib section which is most remote from the pivotal axis of the jib.

Abstract: In a cutting machine (1) comprising cutting heads (5) rotatably supported on a universally swivellable cutting arm (2) and having arranged therein a gearing stage (7), supply of water is effected via the outer front disc (8) of the cutting head and the water flows via passages provided within the interior of the main body (15) of the cutting head to nozzles provided at the circumference thereof. The water supply flows via an essentially axial bore (12) into a cavity of the main body (15) of the cutting head and is passed from this cavity via passages (21, 22, 23) to the nozzles (FIGS. 1,2).

Abstract: A mine drift advancing machine includes a cutting arm pivoted at its rear end to the machine chassis for movement about a horizontal axis and at its front end supporting a carrier which is pivoted to the arm for movement about a vertical axis. At least two horizontally spaced apart rocking levers are pivoted at their rear ends to the carrier for swinging about vertical axes and a lever drive is provided for swinging the levers simultaneously in the same directions. The forward end of each lever carrie at least one cutting tool which is rotatable about a generally vertical axis.

Abstract: A drift advancing or a partial-cut mining machine (1) comprises a cutting arm (11) being swivellable in a height direction around an axis (10). The front end of the cutting arm (11) is equipped with guides (26) transversely extending relative to the longitudinal axis (38) of the cutting arm (11) and having shiftably supported thereon a carrier (27) for the cutting heads (28, 29). The cutting heads (28, 29) are rotatably supported on the carrier (27) for rotation around vertical axes (46). The distance (a) between the axes of rotation (46) is, as measured in a transverse direction relative to the longitudinal axis (38) of the cutting arm, at most equal to half the width (b) of the drift face.

Abstract: A cutting machine (1) includes on its base frame (3) a carrier construction (19) for wall elements (21) and appliances (20) for drilling anchor bores and applying anchors the carrier construction being shiftable in longitudinal direction of the machine. The wall elements (21) are adjoining the drift roof (22) and, respectively, a cutting arm (11) via elastic sealing elements (23). The cutting arm (11) and the charging means (15) are pivotally linked to a shiftable frame (42). The cutting heads (28, 29) can be shifted along guides (31) in transverse relation to the longitudinal axis of the drift, the cutting heads (28, 29) being arranged between drift face (33) and wall elements (21).

Abstract: The device for controlling the position of a tunnelling machine has a housing (2) swivelling about an axis (3), within of which three measuring surfaces (11, 14, 18) are arranged. The first two measuring surfaces (11, 14) have openings of passage (12) for a laser beam (5), the clear width (a, c) of which diminishes in the direction of propagation of the laser beam (5). The clear width (a) of the first measuring surface (11) is smaller than the diameter (e) of the striking area of the laser beam in this measuring surface (11). The receiver elements (13, 16, 17) are arranged symmetrically in relation to the axis of the openings of passage or in case of the last measuring surface (18) in the axis and within the normal projection of the edges of the openings of passage of a preceding measuring surface (FIG. 3).

Abstract: The invention refers to a movable supporting frame for supporting the roof in underground cavities, in particular for securing the excavating edge when recovering the pillars in coal mining, comprising a cap (5) supported against a base frame (1) by means of hydraulically extendable props (3) and a lemniscate drive means (4), the props (3) being pivotally connected with the base frame (1) and with the cap (5). The props (3) are essentially perpendicularly oriented relative to stratification and are linked to the base frame (1) and to the cap (5) in a universally pivotably manner, noting that preferably four props are arranged at the corners of a rectangle as seen in a plan view. The lemniscate drive means (4) is connected with the base frame (1) for swivelling movement in transverse direction relative to the plane defined by the lemniscate guides (8, 9) and is adjustably supported against any swivelling movement and is connected with the cap (5) for universal swivelling movement.

Abstract: For protecting partial-cut cutting machines from overload, a vibration sensor 7 is provided on the swivellable cutting arm 2 carrying rotatably supported cutting heads 6. The signals of the vibration sensor 7 are utilized in an electronic control 8 and used for controlling the pivotal drive of the cutting arm 2. The electronic control 8 has a threshold switch which is connected with an adjusting drive for varying the supply capacity of the hydraulic pump of the pivotal drive.

Abstract: For reducing the risk of any overheating when cutting or crushing rock by means of a partial cut cutting machine and for facilitating crushing or, respectively, cutting of the material, a pressurized liquid, for example water, is intermittently sprayed within an area facing the area to be excavated. Said mentioned area facing the area to be excavated is realized in connection with a cutting head by providing within a range of center angle of the rotating movement of the cutting head a plurality of radial perforations (18) adjoining an axial bore (8) for the supply of pressurized fluid, noting that this range of central area corresponds to that area which faces the area to be excavated or, respectively, the mine face. Radial channels (22) of the cutting head coincide during rotation of the cutting head (1) with the radial perforations (18), said channels feeding the pressurized liquid to the exit openings provided on the periphery of the cutting head (1).

Abstract: With cutting machines, having their loading means (7) adapted to be lowered below the running surfaces (11) of the crawlers (2) of the drift advancing machine, there results an erroneous position of the machine on account of lifting the front end of the machine during such lowering movement of the loading means (7). For establishing the correct position of the cutting tool (6) and of the cutting arm (5), corrective signal are used which are released by angular position transmitters (16 or 17, respectively). By means of these angular position transmitters (16 or 17, respectively), the swivelling angle of the loading means (7) relative to the frame (1) or the swivelling angle .theta. of the operating cylinder (9) of the loading means (7) relative to the frame (1), respectively, is measured and the required corrective signal for the angle advance .DELTA..alpha. is calculated (FIG. 3).

Abstract: The loading ramp (1) of a heading machine or longwall shearing machine has swivelable loading arms by means of which the cut material is removed onto a conveying means. The surface of the loading ramp (1) can be increased by outwardly swivelling of parts (2). The loading arms (5) are driven by using a pivotal point (6) on a rotary disc (7), noting that a further swivel point (12) is provided outwardly of the circle described by a rotary pivotal point (6) on the rotary disc. The loading arm (5) is guided in a shiftable manner at the swivel point (12) and sweeps when driving the rotary disc (7) over a removal area (15, 18) defined by the relative position of the pivotal point (6) and the swivel point (12). The swivel point (12) is connected with the laterally extendable part (2) and is displaced together with the laterally extendable part (2) thus varying the removal area (15, 18).

Abstract: A bit holder equipped with a spraying device, comprising a receiving bore (2) in which the bit shaft (3) is supported, for limited axial shifting movement and optionally for being rotated, shifting movement of the bit shaft (3) in direction of the cutting pressure being limited by abutment (5) and the bit shaft being loaded by a return force in opposite direction to the cutting pressure and a valve (10, 11) for the supply of water to the bit or to the working or drift face during cutting operation being arranged within the bit holder (1) and being opened under the action of the cutting pressure by the axial shifting movement of the bit shaft (3). The valve housing (9) is inserted into the receiving bore (2). The rear end of the bit shaft (3) acts directly on the shaft (12) of the valve cone (10).

Abstract: For cooling the bits (1) of a cutting machine, nozzles (22) for cooling water are provided. The bit (1) is supported for axial shifting movement and can when being loaded exert a stroke for the path (a) in direction of the arrow (4). A coupling member (9) transmits the movement of the bit (1) to a shutoff valve (7) blocking the supply of water in unloaded condition of the bit and giving free the supply of water whenever a predetermined cutting pressure is exceeded. The restoring force of the bit (1) to return the same in its starting position in unloaded condition is provided by a spring (5) and by the water pressure and is rated in correspondence with the minimum value of the cutting pressure. The restoring spring (5) is supported against an adjustable abutment (30, 31) which can be fixed in position during operation so that the restoring force can be adjusted.

Abstract: The bits (1) of a cutting machine are subjected with water under pressure by means of nozzles (22), water supply to the nozzles (22) being given free by a valve cone (6) as soon as the bit (1) within the bit holder (2) is shifted in axial direction against the force of a spring. Axial movement of the bit (1) is effected by the cutting pressure and the shifting path of the bit (1) is transmitted to the valve cone (6) via a coupling member (9). The force of the spring (5) is rated such that the spring presses the bit (1) against its own weight and against the internal frictional resistances into its starting position in non-loaded condition with simultaneous closing of the valve cone (6). The restoring forces are, with connected conduits for pressurized water, substantially greater than the spring force, the active surface of the valve cone (6) acted upon by the water pressure in closing sense determining the force above which opening of the valve becomes possible.

Abstract: The invention refers to a system for cooling the bits of a cutting machine and comprising a nozzle for the cooling water to be ejected under pressure, said nozzle being arranged at the area of the bit, the water supply to said nozzle being closable by means of a shutoff valve and the bit being supported on the bit holder for limited axial shifting movement under the action of the cutting pressure against the force of a spring and against the hydraulic pressure of the cooling water and the shutoff valve being coupled with the bit by means of a coupling member such that the shutoff valve is opened on shifting movement of the bit in direction of the cutting pressure.

Abstract: The system for monitoring the movement of a cutter arm and of the cutting tools rotatably mounted on said cutter arm in a tunnel-driving machine comprises a receiver (13), which has a sighting device (14) that is mounted to be displaceable and pivotally movable transversely to the longitudional axis of the tunnel-driving machine. The movement of the receiver (13) to a position in alignment with a guide beam (3) is transmitted to a simulator, which contains a model (62) of the desired profile and in which a three-dimensional scale model (54) of the cutting tool is mounted to be pivotally movable and displaceable analogously to the receiver (13) (FIGS. 4 to 11).

Abstract: A hydraulic mine prop includes an inner piston-like prop guided within an outer cylinder-like prop, and a roof fall valve. The interior space of said inner prop communicates freely with the working chamber of the prop, and the roof fall valve is arranged outwardly on the prop and rigidly secured thereon, the valve being connected to the working chamber by an orifice provided in the prop and leading to the working chamber. The cross-sectional area of the roof fall valve in its open position.

Abstract: For sinking of shafts, a cutting machine (1) is provided having its cutting arm (3) pivotable around a vertical axis (4) and a horizontal axis (5). The cutting arm (3) carries cutting heads (14) which are rotatable around an axis (15) horizontally arranged and extending perpendicularly relative to the axis of the cutting arm. The shaft is now sunk around its circumference (9) in direction of its axis (10), for which purpose first the uppermost lead of a screw surface is prepared. On this uppermost lead of the screw surface the cutting machine is advanced until the cutting heads (14) contact the shaft wall (9). In the following, a floor cut (19) is made whereupon a further floor cut (20) is made at a lower level. Starting from a corresponding position of the cutting machine surfaces (23, 24) are cut free starting from the shaft wall (9).

Abstract: For reducing the amount of water consumed, supply of water to the cutting head of a cutting machine shall be given free only if different operating conditions are simultaneously occurring. The proposed process contemplates to provide the possibility to supply water to the cutting head only with the rotational movement of the cutting head being switched-on and to give free the water supply only if simultaneously at least one further operating condition such as, for example, a movement of the cutting arm or a movement of the machine is occurring.The apparatus for performing this process contemplates a device for switching-in a water pump, said device being coupled with a device for switching-in the rotational drive of the cutting head.

Abstract: In apparatus for controlling the position of a drift advancing machine having a longitudinal axis: two light beam sources or laser beam sources spaced longitudinally from the machine, the sources emitting beams which are parallel to each other and to the drift axis and which are in different vertical planes extending longitudinally of the drift; and two beam receivers arranged on the machine, the receivers being in transversely spaced apart positions relative to the longitudinal axis of the machine, and the transverse distance between the receivers corresponding to the transverse distance between the two beams.