TECHNICAL FIELD
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The present disclosure relates to a cutterhead system, a rock cutting machine and methods therefore, and in particular, although not exclusively, to undercutting machine in which one or more rotating cutterheads are capable of being slewed forward and raised in the upward and downward direction during forward cutting.
BACKGROUND
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A variety of different types of excavation machines have been developed for cutting drifts, tunnels, subterranean roadways and the like in which a rotatable head is mounted on an arm that is in turn movably mounted at a main frame so as to create a desired tunnel cross sectional profile.
WO2012/156841 ,
WO 2012/156842 ,
WO 2010/050872 ,
WO 2012/156884 ,
WO2011/093777 ,
DE 20 2111 050 143 Ul all described apparatus for mill cutting of rock and minerals in which a rotating cutterhead forced into contact with the rock face as supported by a movable arm. In particular,
WO 2012/156884 describes the cutting end of the machine in which the rotatable heads are capable of being raised and lowered vertically and deflecting in the lateral sideways direction by a small angle in an attempt to try to enhance the cutting action.
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WO 2014/090589 describes a machine for digging roadways tunnels and the like in which a plurality of cutterheads are movable to dig into the rock face via a pivoting arcuate cutting path.
US 2003/0230925 describes a rock excavator having a cutter head mounting a plurality of annular disc cutters suitable to operate in an undercutting mode.
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However, conventional cutting machines are not optimised to cut hard rock having a strength typically beyond 120 MPa whilst creating a tunnel or subterranean cavity safely and reliably of desired cross sectional configuration. A known system devised for cutting hard rock is disclosed in
WO2016/055087 .
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A challenge faced by known systems, in particular when employed to cut hard rock, is the generation of mechanical vibrations in the equipment. Such vibrations may have adverse effects or be detrimental to the equipment and may impact operation or longevity of the equipment negatively. As such, there is room for improvement in the field.
SUMMARY
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It is an objective of the present disclosure to provide a cutting machine suitable to form tunnels and subterranean roadways being specifically configured to cut hard rock beyond 120 MPa in a controlled and reliable manner. It is a further specific objective to provide a cutting machine capable of creating a tunnel with a variable cross sectional area within a maximum and a minimum cutting range. It is a further specific objective to provide a cutting (excavator) machine operable in an 'undercutting' mode.
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There is disclosed a cutterhead system for engaging with a rock working face, comprising a cutterhead carrier comprising a first section (e.g. an upper section) and a second section (e.g. a lower section), wherein the second section is configured to be rotatable relative to the first section about a pivot axis, that may be the tertiary pivot axis according to embodiments of the disclosure; at least one rotatable cutterhead mounted to the second section of the cutterhead carrier, a respective cutterhead of the at least one cutterhead(s) rotatable about a respective cutterhead rotational axis; a plurality of roller cutters independently rotatably mounted at each rotatable cutterhead, a respective roller cutter being rotatable about a respective roller cutter rotational axis arranged at an angle relative to the cutterhead rotational axis. The angle may be a fourth angle according to embodiments of the disclosure and may be in the range of 60 to 90 degrees.
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In an embodiment the respective cutterhead rotational axis is substantially transverse to the pivot axis. Optionally, when the cutterhead system comprises a single cutterhead, the cutterhead rotational axis and the pivot axis may substantially lie in the same plane.
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In an embodiment, the cutterhead system comprises a pair of the cutterheads, the cutterheads of the pair of cutterheads are arranged symmetrically about and offset from the pivot axis, preferably, the cutterheads are configured to be driven to rotate in opposite directions about their respective cutterhead rotational axes.
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In an embodiment the cutterhead carrier comprises a turret, wherein the first section and the second section form (or form part of) the turret.
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There is disclosed a rock cutting machine for creating tunnels or subterranean roadways and the like in a machine direction along a horizontal plane, comprising a main frame extending in the machine direction orthogonal a main frame vertical extension and a main frame lateral extension, and a frontal cutterhead system for engaging with a rock working face.
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The cutterhead system comprises a support connected to the main frame, the support may be pivotably connected to the main frame, such as to be pivotable about a secondary pivot axis that may be oriented vertical.
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An arm is provided pivotably mounted to the support via a primary pivot joint having a primary pivot axis that may extend and/or oriented laterally, such as horizontal and transverse to the machine direction. At least one arm actuator is provided for effecting angular movement of the arm, the angular movement of the arm may translate to an arcuate motion path of the cutterhead(s) in a vertical plane, hence the motion path may be arc-circular about the primary pivot axis. Preferably, the arm actuator comprises a slewing gear.
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The cutterhead carrier may comprise any of the feature of the arm according to embodiments of the disclosure. Likewise, the arm may comprise any of the features of the carrier according to embodiments of the disclosure.
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One or more rotary cutterhead are provided rotatably mounted to the arm via a cutterhead housing fixed to the arm, for example, at the distal end, offset from the primary pivot axis A1. a respective cutterhead of the one or more cutterhead(s) being rotatable about a respective cutterhead rotational axis. A respective cutterhead rotational axis may be arranged in a respective vertical plane.
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A vertical plane in the context of the disclosure generally encompasses a vertically extending plane that is parallel to the cutterhead rotational axis.
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In an embodiment a plurality of roller cutters are provided independently rotatably mounted at each rotatable cutterhead, each roller cutter rotatable about a roller cutter rotational axis arranged substantially perpendicular to the cutterhead rotational axis.
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A respective cutterhead rotational axis may be transverse to the arm, in particular transverse to a longitudinal extension of the arm between the primary pivot joint and the cutterhead and/or the cutterhead housing. A respective cutterhead rotational axis may extend perpendicular to the primary pivot axis.
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A respective cutterhead rotational axis may be tangent, substantially tangent or semi-tangent to the arcuate motion path. The motion path may be seen as a cutting path along which the cutterheads will cut rock in the rock working face.
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The machine comprises means for manipulating a position of the cutterhead(s) laterally, such as pivoting the cutterhead(s) in a horizontal plane and/or as seen in a horizontal plane.
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In some embodiments the angular movement of the arm may translate to a curvilinear motion of the cutterhead rotational axis about the primary pivot axis. In particular a curvilinear motion along the motion path.
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In some embodiments the angular movement of the arm may translate to an upwards and forwards directed arcuate movement of the cutterhead(s) from a lower retracted position wherein the cutterhead rotational axis is arranged generally parallel or parallel to the horizontal plane, to an a raised advanced or extended position wherein the cutterhead rotational axis is arranged generally vertical and/or transverse to the machine direction and/or transverse a cutting direction. Put differently, the retracted position may be a folded position where the arm is folded toward the main frame, and the advanced position may be an unfolded position where the arm is projecting away from the main frame.
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As has been explained hereinbefore, in some embodiments a respective cutterhead of the one or more cutterhead(s) comprises a plurality of roller cutters arranged to revolve around the cutterhead rotational axis) in response to rotation of the cutterhead. A respective roller cutter of the plurality of roller cutters may be independently rotatable about a respective roller cutter rotational axis arranged substantially transverse the cutterhead rotational axis.
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The plurality of roller cutters may be generally annular roller cutters each having a generally annular cutting edge or layered cutting edges to provide an undercutting mode of operation.
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The rock working face may extend generally transverse to the machine direction. The rock working face may be arcuate. The rock working face may comprise an arcuate cross-section in a vertical plane parallel to the machine direction and/or the cutting direction. The cutterhead, in particular the roller cutters, more in particular a cutting edge of the roller cutters, may be configured to attack the rock working face semi-tangentially or tangentially. That is, at an angle that is semi-tangential to the rock working face. The roller cutters may be configured to attack the rock working face with an undercutting action.
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In an embodiment the machine comprising means for pivoting the support relative to the main frame for allowing the support to pivot laterally in a horizontal plane about a secondary pivot axis, and at least one support actuator is for effecting the pivoting of the support.
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In some embodiments the means for pivoting the support comprises the support being pivotably mounted to the main frame via a pivot coupling having a secondary pivot axis for allowing the support to pivot along the horizontal plane, and at least one support actuator for effecting the pivot along the horizontal plane. The secondary pivot axis may be vertical.
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The arm may comprise means for pivoting the cutterhead(s) about a tertiary pivot axis aligned in a direction perpendicular to the primary pivot axis, optionally a respective cutterhead rotational axis is oriented substantially transverse to the tertiary pivot axis.
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In some embodiments the means for pivoting the cutterhead(s) about the tertiary pivot axis comprises the one or more rotatable cutterhead being rotatably connected to the arm via a turret or like mechanism having the tertiary pivot axis aligned in a direction perpendicular to the primary pivot axis for allowing the cutterhead (s) to turn along the horizontal plane. A respective cutterhead rotational axis is oriented substantially transverse to the tertiary pivot axis.
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In some embodiments the one or more cutterheads comprises a plurality of cutterheads, such as two cutterheads, preferably the rotational axes of the plurality of cutterheads are mutually fixed, such as in a parallel arrangement. Thus, a turning motion of the turret may in some embodiments translate to a curvilinear movement of a respective cutterhead rotational axis about the tertiary pivot axis.
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In one embodiment, a pair of cutterheads are provided, the cutterheads are arranged symmetrically about and offset from the tertiary pivot axis, with the cutterhead rotational axis being substantially perpendicular to the tertiary pivot axis, preferably, the cutterheads may be driven to rotate in opposite directions about their respective cutterhead rotational axes. Preferably, the cutterheads are arranged such that, regardless of the arm's gesture, the primary pivot axis remains parallel to a plane defined by respective cutterhead rotational axes and maintains a constant perpendicular distance from the plane.
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In some embodiments the plurality of roller cutters comprising at least eight roller cutters, preferably ten to fourteen, such as thirteen roller cutters.
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In some embodiments the cutting machine comprises a hydraulic drive for effecting rotation of the cutterhead(s).
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In some embodiments the cutting machine comprises a ground engaging support connected to the arm and extending beyond a cutterhead outer periphery for supporting the cutterhead system in a retracted position.
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In some embodiments the primary pivot joint is configured to pivot or slew the arm a first angle about the primary pivot axis. The first angle may be up to 180 degrees, preferably at least 100 degrees, preferably about 108 degrees.
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In some embodiments the means for pivoting the support are configured to pivot or swing the support a second angle about the secondary pivot axis. The second angle may be up to 90 degrees, preferably at least 40 degrees, such as about 52 degrees.
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In some embodiments the means for pivoting the cutterheads are configured to swivel or rotate or pivot the cutterhead(s) a third angle about the tertiary pivot axis. The third angle may be up to 90 degrees, preferably at least 60 degrees, such as about 74 degrees.
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In some embodiments, a respective roller cutter rotational axis forms with a respective cutterhead rotational axis a fourth angle that is in the range of 60 to 90 degrees, preferably 70 to 80 degrees.
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Optionally, each cutterhead comprises a generally annular cutting edge or layered cutting edges to provide an undercutting mode of operation. The configuration of each cutterhead to provide the undercutting action is advantageous to break the rock with less force and in turn provide a more efficient cutting operation that draws less power. Preferably, the machine comprises a plurality of roller cutters independently rotatably mounted at each rotatable cutterhead.
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The roller cutters may be generally annular roller cutters each having a generally annular cutting edge or layered cutting edges to provide an undercutting mode of operation. More preferably, the roller cutters are mounted at a perimeter region of each cutterhead such that the roller cutters circumferentially surround each cutterhead. Such a configuration is advantageous to provide the undercutting action of the machine with the roller cutters first creating a channel or groove extending generally horizontally in the rock face. The roller cutters may then be moved upwardly to break the rock by overcoming the tensile forces immediately above the channel or groove. A more efficient cutting operation is provided requiring less force and drawing less power.
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The roller cutters may be mounted at generally cylindrical bodies and comprise generally annular cutting edges distributed around the perimeter of the cutterhead. Each generally circular cutting edge is accordingly positioned side-by-side around the circumference of the cutterhead with each cutting edge representing a radially endmost part of each cutterhead periphery. Preferably the respective rotational axes of the roller cutters of a respective cutterhead of the one or more cutterheads is aligned substantially perpendicular relative to the rotational axis of the cutterhead so that the respective cutting edges are all orientated in the same position around the cutterhead.
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The cutterheads may comprise a plurality of the disc-like roller cutters distributed circumferentially around a perimeter of each head so as to create a groove or channel into the rock face as the cutterheads are driven about their respective rotational axes. The cutterhead(s) may then be raised vertically so as to overcome the relatively low tensile strength of the overhanging rock to provide breakage via force and energy that is appreciably lower than a more common compressive cutting action provided by cutting picks and the like.
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The machine may further comprise at least one second drive motor to drive rotation of the cutterhead(s) at the arm. Preferably, each cutterhead comprises a drive motor mounted at the arm. Such an arrangement is advantageous to pivot the drive motor with each cutterhead and to provide a direct drive with minimal intermediate gearing.
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The machine may further comprise a powered sled movably mounted at the main frame to be configured to slide in a forward direction of the machine relative to the main frame. In this case, a frontal cutterhead system is arranged on the sled instead of directly on the main frame. The machine may further comprise a plurality of 'runners' or guide rails to minimise the factional sliding movement of the sled over the main frame. Preferably, the machine comprises at least one powered linear actuator to provide the forward and rearward movement of the sled relative to the main frame. As will be appreciated, the sled may be configured to move axially/longitudinally at the machine via a plurality of different actuating mechanisms including rack and pinion arrangements, belt drive arrangements, gear arrangements and the like. Preferably the support with the arm is mounted at the sled and is configured to move in the forward and rearward direction collectively.
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The support actuator may comprise a hydraulic linear actuator. The support actuator may comprise a linear hydraulic cylinder. The linear hydraulic cylinder may be positioned at lateral sides of the sled and coupled to extend between the sled and an actuating flange extending laterally outward from the support.
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The machine may comprise tracks or wheels mounted at the main frame to allow the machine to move in a forward and rearward direction. The tracks or wheels enable the machine to be advanced forwardly and rearwardly within the tunnel both when maneuvered into and from the cutting face between cutting operations and to be advanced forwardly during cutting operations as part of the cut-and-advance cutting cycle that also utilises the sliding sled.
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In one embodiment, the machine may further comprise floor and roof engaging members mounted at the main frame, at least the floor engaging members being extendable and retractable to respectively raise and lower the machine in the upward and downward direction. The engaging members are configured to wedge the machine in position between the roof and floor of the tunnel to provide points of anchorage against which the machine may be braced to allow the cutterheads to be forced against the rock working face.
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The machine may further comprise a first material discharge conveyor to convey cut material rearwardly from the first and second cutterhead; and a gathering head to direct cut material onto the conveyor, the gathering head positioned rearwardly behind one or more cutterheads. The machine is accordingly configured to transport rearwardly material from the cut face to provide unhindered forward cutting movement into the rock.
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The machine may further comprise a control unit demountably connectable to the machine, the control unit comprising operational components to power at least the first and second support and arm actuators, the control unit further comprising a second conveyor to receive material from the first conveyor and to discharge the material at a position rearward of the machine and the control unit. Preferably, the control unit is demountably coupled to the machine so as to be capable of being advanced and retracted in the forward and rearward directions with the cutting machine. Preferably, the control unit is suspended above the tunnel floor by suitable couplings to the machine. The control unit may comprise ground engaging support members provided at a rearward and/or forward regions. Optionally, the control unit may be attachable at its rearward end to a material collection and discharge vehicle and to be connectable at its forward end to the cutting machine.
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There is disclosed a cutting method for a rock cutting machine, which may be the cutting machine according to embodiments of the disclosure, for creating tunnels or subterranean roadways, the cutting machine comprising a main frame having a machine direction orthogonal a main frame vertical extension and a main frame lateral extension, and one or more frontal cutterheads rotatable about a respective cutterhead rotational axis arranged along a cutting direction as seen in a horizontal plane. The method comprises setting a respective rotational axis along, such as parallel, a first cutting direction in a horizontal plane; rotating a respective cutterhead about its respective rotational axis; performing a first cutting movement by an advancing first angular motion of the cutterhead(s) in a vertical plane in the first cutting direction, and preferably performing a corresponding opposite retracting movement by an opposite retracting angular motion.
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In some embodiments the method comprises adjusting the cutting direction and optionally performing a second cutting movement and/or an opposite fifth cutting movement by displacing the cutterhead(s) along the horizontal plane, such as by a second angular motion and/or an opposite fifth angular motion of the cutterhead(s), such as about a tertiary pivot axis that may be distal relative to the frame.
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In some embodiments the method comprises adjusting the cutting direction and optionally performing a third cutting movement and/or an opposite sixth cutting movement by an angular motion of the cutterhead(s) laterally along the horizontal plane, such as a third angular motion and/or a sixth angular motion relative a proximal secondary pivot axis relative the frame and/or relative to the tertiary pivot axis.
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In some embodiments the method comprises performing the second cutting movement by the second angular motion, which may be a curvilinear motion, of the cutterhead(s) about the tertiary pivot axis with the cutterhead rotational axes generally oriented parallel a horizontal plane.
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In some embodiments the method comprises performing the third cutting movement by the third angular motion of the cutterhead(s), such as about the secondary pivot axis, preferably with the cutterhead(s) rotational axes generally oriented parallel the horizontal plane.
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In some embodiments the method comprises performing the fourth cutting movement in a second cutting direction different from the first cutting direction by the first angular motion of the cutterhead(s) in a vertical plane, and preferably an opposite retracting movement by a corresponding opposite angular motion.
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In some embodiments the method comprises performing the fifth cutting movement by the fifth angular motion, which may be a curvilinear motion, of the cutterhead(s) about the tertiary pivot axis with the cutterhead rotational axes generally oriented parallel a horizontal plane.
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In some embodiments the method comprises performing the sixth cutting movement by an angular motion, such as the sixth angular motion, such as about the secondary pivot axis, preferably with the cutterhead rotational axes generally oriented parallel the horizontal plane.
BRIEF DESCRIPTION OF DRAWINGS
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A specific implementation of the subject disclosure will now be described, by way of example, and with reference to the accompanying schematical drawings in which:
- FIG. 1A is a side view of the mobile rock cutting machine according to an embodiment of the disclosure.
- FIG. 1B is a front perspective view of the rock cutting machine of FIG. 1.
- FIG. 2A shows the cutterhead system according to an embodiment of the disclosure.
- FIG. 2B is a schematic illustration of the first angular motion of the arm according to an embodiment of the disclosure.
- FIG. 2C is a schematic illustration of a pivoting motion of the support according to an embodiment of the disclosure.
- FIG. 2D is a schematic illustration of a rotating motion of the turret according to an embodiment.
- FIG. 3 shows the first cutting movement according to an embodiment.
- FIG. 4 shows the retracting movement according to an embodiment.
- FIG. 5 shows the second cutting movement according to an embodiment.
- FIG. 6 shows the third cutting movement according to an embodiment.
- FIG. 7 shows the fourth cutting movement according to an embodiment.
- FIG. 8 shows the retracting movement according to an embodiment.
- FIG. 9 shows the fifth cutting movement according to an embodiment.
- FIG. 10 shows the sixth cutting movement according to an embodiment.
- FIG. 11 shows the rock work face and the cutterhead system according to an embodiment.
- FIG. 12 shows the rock work face and the floor upon performing the rock cutting method according to embodiments of the disclosure.
- FIG. 13 shows the method for a rock cutting machine according to an embodiment of the disclosure.
DETAILED DESCRIPTION
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Referring to FIG. 1A and FIG. 1B, cutting machine 100 comprises a main frame 102 mounting a plurality of cutting components configured to cut into a rock or mineral face to create tunnels or subterranean roadways. Machine 100 is configured specifically for operation in an undercutting mode in which a plurality of rotatable roller cutters 130 may be forced into the rock to create a groove or channel and then to be pivoted vertically upward so as to overcome the reduced tensile force immediately above the groove or channel and break the rock. Accordingly, the present cutting machine is optimised for forward advancement into the rock or mineral utilising less force and energy typically required for conventional compression type cutters that utilise cutting bits or picks mounted at rotatable heads. However, the present machine may be configured with different types of cutterhead to those described herein including in particular pick or bit type cutterheads in which each pick is angularly orientated at the cutterhead to provide a predetermined cutting attack angle.
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Main frame 102 comprises lateral sides 302 to be orientated towards the wall of the tunnel; an upward facing region 300 to be orientated towards a roof of the tunnel; a downward facing region 301 orientated to be facing the floor of the tunnel; a forward facing end 303 intended to be positioned facing the rock working face 140 and a rearward facing end 304 intended to be positioned facing away from the rock working face 140 (see also FIG.3).
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An undercarriage 109 is mounted generally below main frame 102 and in turn mounts a pair of crawler tracks 103 driven by a hydraulic (or electric) motor to provide forward and rearward movement of machine 100 over the ground when in a non-cutting mode. A pair of rear ground engaging jacking legs 106 are mounted at frame sides 302 towards rearward end 304 and are configured to extend and retract linearly relative to frame 102. Frame 102 further comprises a forward pair of jacking legs 115 also mounted at each frame side 302 and towards forward end 303 and being configured to extend and retract to engage the floor tunnel. By actuation of legs 106, 115, main frame 102 and in particular tracks 103 may be raised and lowered in the upward and downward direction so as to suspend tracks 103 off the ground to position machine 100 in a cutting mode. A pair of roof engaging grippers 105 project upwardly from main frame 102 at frame rearward end 304 and are extendable and retractable linearly in the upward and downward direction via control cylinders 116. Grippers 105 are therefore configured to be raised into contact with the tunnel roof and in extendable combination with jacking legs 106, 115 are configured to wedge machine 100 in a stationary position between the tunnel floor and roof when in the cutting mode.
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A sled 104 is slidably mounted at the main frame 102, such as in the main frame, via a slide mechanism. Sled 104 is coupled to a linear hydraulic cylinder 201 such that by reciprocating extension and retraction of cylinder 201, sled 104 is configured slide linearly between frame forward and rearward ends 303, 304.
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A pair of hydraulically actuated bolting units 107 are mounted at main frame 102 between sled 104 and roof gripping unit 105, 116 relative to a lengthwise direction of the machine. Bolting units 107 are configured to secure a mesh structure (not shown) to the roof of the tunnel as machine 100 is advanced in a forward cutting direction. Machine 100 also comprises a mesh support structure mounted generally above sled 104 so as to positionally support the mesh directly below the roof prior to bolting into position.
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The machine 100 may be for creating tunnels or subterranean roadways and the like in a machine direction X along a horizontal plane XZ. The machine 100 comprises a main frame 102 extending in the machine direction X orthogonal a main frame vertical Y extension and a main frame lateral Z extension.
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With added reference to FIG. 2A a frontal cutterhead system 110 is provided. The frontal cutterhead system 110 may be configured for engaging with a rock working face 140. A support 120 is provided connected to the main frame 102. An arm 122 is pivotably mounted to the support 120 at a primary pivot axis A1, and at least one arm actuator 123 for affecting angular movement A11, A11, A12, A12' of the arm 122 in a vertical plane, such as the XY plane. The machine direction X may be seen as a longitudinal direction of the main frame 102 of the machine 100.
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One or more rotary cutterhead 128, 128' are provided rotatably mounted to the arm 122, such as via a respective cutterhead housing. A respective cutterhead of the one or more cutterhead(s) are rotatable about a respective cutterhead rotational axis A4, A4'.
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The cutterhead carrier 126 comprises an upper section and a lower section/rotatable section. The lower section is configured to be rotatable relative to the upper section about a pivot axis, that may be the tertiary pivot axis A3 according to embodiments.
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The at least one rotatable cutterhead 128, 128' is mounted to the lower section of the cutterhead carrier 126. A respective cutterhead of the at least one cutterhead(s) is rotatable about a respective cutterhead rotational axis A4, A4'.
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The angular movement of the arm A11, A11, A12, A12' may comprise movement at least between a lower folded and/or retracted position and an advanced and/or unfolded position. The arm may thus be allowed to move from the retracted position in a forwards and upwards direction to the advanced position. In the retracted position the arm 122 has a generally vertical alignment and the cutterhead(s) are disposed beneath, such as immediately beneath, the primary pivot joint 121, the cutterhead rotational axis A4, A4' being aligned generally horizontal. In the advanced position the arm 122 has a generally horizontal alignment, the cutterhead(s) are disposed advanced or in front of the primary pivot joint 121 and the cutterhead rotational axis A4, A4' is aligned generally vertical.
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The cutterheads 128, 128' are juxtaposed, in the retracted position, immediately below the primary pivot joint, which may be provided in shape of a slew drive. In the retracted position, the arm 122 may extend in a direction generally vertically downwards from the primary pivot joint 121.
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A slew drive is a mechanical device used to rotate or turn large loads with precision and control. It typically consists of a combination of a worm gear and a slewing ring, and is often used in applications that require rotation or positioning.
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The cutterheads are juxtaposed, in the advanced position, in front of the primary pivot joint 121. In the advanced position, the arm 122 may extend in in a generally horizontal and forward direction from the primary pivot joint.
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In some embodiments the, the angular movement of the arm A11, A11, A12, A12' comprises or translates to an arcuate upwards movement along a motion path MP. The first cutting movement may be at least from a retracted position wherein a respective cutterhead rotational axis A4 is arranged generally horizontal, and at least to an advanced position wherein a respective cutterhead rotational axis A4 is arranged generally vertical. The machine it thus configured to perform a cutting movement, and thus cut rock, whilst displacing the arm angularly in a forward and upward direction.
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With added reference to FIG. 2B, in some embodiments the angular movement of the arm 122 may translate to a curvilinear motion of the cutterhead rotational axis A4, A4' about the primary pivot axis A1.
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A respective cutterhead of the one or more cutterhead(s) 128, 128' may comprise a plurality of roller cutters 130 arranged to revolve about the cutterhead rotational axis A4 in response to rotation of the cutterhead 128. A respective roller cutter of the plurality of roller cutters 130 may be rotatable about a respective roller cutter rotational axis A5, A5' arranged substantially transverse to the cutterhead rotational axis A4, A4'. The roller cutters may each comprise a generally circular cutting edge 131 disposed in a plane substantially parallel, or parallel to the cutterhead rotational axis A4 and/or transverse to the roller cutter rotational axis A5, A5'.
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Means 118 for pivoting the support 120 relative to the main frame 102 about a secondary pivot axis A2 is provided. The means 118 may comprises the support 120 being pivotably mounted to the main frame 102 via a pivot coupling 118 having a secondary pivot axis A2 (that may be a proximal pivot axis in relation to the frame). The secondary pivot axis A2 may be vertical, for allowing the support 120 to pivot along the horizontal plane XZ as shown in FIG. 2C. At least one support actuator 117 may be provided for affecting the pivot along the horizontal plane XZ. The support actuator 117 may act on the actuating flange 118a, 118b extending laterally from the support 120 for improved control of the support. Preferably, respective actuating flanges 118a, 118b are provided extending from the support 120 in opposite lateral directions, and a respective support actuator 117 is provided to act on a respective actuating flange of the opposite flanges 118a, 118b.
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The arm 122 comprises means 124 for pivoting the cutterhead(s) about a tertiary pivot axis A3. The means 124 may be for rotatably connecting the one or more rotatable cutterhead 128, 128' to the arm 122. The tertiary pivot axis A3 may be aligned in a direction perpendicular to the primary pivot axis A1 for allowing the cutterhead (s) to turn A31, A32 along the horizontal plane XZ. In an embodiment, the means 124 comprises a turret 124 having the tertiary pivot axis A3. A respective cutterhead rotational axis A4, A4' may be oriented transverse to the distal rotational axis A3 as shown in FIG. 2D. A turning motion of the means 124, which may be the turret 124, may translate to a curvilinear movement of a respective cutterhead rotational axis A4, A4' about the tertiary pivot axis A3.
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A turret is a rotating or swiveling structure that houses equipment or machinery, commonly used in engineering applications. It allows the mounted equipment to rotate or pivot, providing versatility in aiming or directing the equipment. Turrets are typically designed to withstand heavy loads, provide full 360-degree rotation, and offer stability during operation.
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The one or more cutterheads may comprise a plurality of cutterheads 128, 128', such as two cutterheads 128, 128'. The cutterhead rotational axes A4, A4' of the plurality of cutterheads may be mutually fixed, such as in a parallel arrangement. By employing two cutterheads, the cutting efficiency of the machine 100 is thus increased.
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The cutterhead rotational axis A4, A4' of the one or more cutterheads and the primary pivot axis A1 may be arranged in parallel planes.
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In the embodiment shown, a pair of cutterheads 128, 128' are provided, the cutterheads are arranged symmetrically about and offset from the tertiary pivot axis A3, with the cutterhead rotational axis A4, A4' being substantially perpendicular to the tertiary pivot axis A3, preferably, the cutterheads 128, 128' may be driven to rotate in opposite directions about their respective cutterhead rotational axes A4, A4'. Preferably, the cutterheads 128, 128' are arranged such that, regardless of the arm gesture or arm position, the primary pivot axis A1 remains parallel to a plane defined by the cutterhead rotational axes A4, A4' and maintains a constant perpendicular distance from the plane.
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The plurality of roller cutters 130 may comprise at least eight roller cutters 130, preferably ten to fourteen, such as thirteen roller cutters.
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The cutting machine 100 may comprise a hydraulic drive for affecting rotation of the cutterhead(s). For example, a respective hydraulic drive may be provided for a respective cutterhead.
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The machine 100 may comprise a cutterhead ground support 132 connected to the arm 122. The cutterhead ground support 132 may be one or more jacking leg for supporting the cutterhead system 110. The cutterhead ground support 132 may be configured to extend beyond a cutterhead outer periphery. As derivable from FIG. 1a and FIG. 1b, the sled 104 is connected at each lateral side to a respective sled jacking leg 119. Thereby, cutterhead ground support 132 and sled jacking leg 119 together can support the sled and the cutterhead system 110. By this configuration, the sled 104 and the cutterhead system 110 may be held stationary relative to the rock working face 140 whilst the main frame is displaced forward, such as by aid of tracks 103. This means that a new cutting cycle may be initiated with the cutterhead system 110 from a position that is essentially the same as a finishing or end position of a preceding cutting cycle, without need for calibration of the cutterhead system 110 in relation to the rock working face 140.
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The cutterhead system 110 may be configured to engage with a rock working face 140. The rock working face may typically extend generally transverse to the machine direction X. The one or more cutterhead(s) 128, 128' may be configured to attack the rock working face 140 with the cutterhead rotational axis A4, A4' arranged substantially tangential and/or substantially parallel to the working face 140 when performing one or more of the rock cutting movement S206A, S212A.
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Put differently, the rock working face 140 may extend generally transverse to the machine direction X. The rock working face may be arcuate. The rock working face 140 may comprise an arcuate cross-section in a vertical plane parallel to the machine direction X and/or the cutting direction C. The cutterhead 128. 128', in particular the roller cutters 130, more in particular a cutting edge 131 of the roller cutters 130, may be configured to attack the rock working face 140 semi-tangentially. For example, at an angle that is semi-tangential to the arcuate cross-section of the rock working face 140 and/or the arcuate motion path MP of the cutting edge 131, as schematically illustrated in FIG. 2B. Preferably, the roller cutters 130 are configured to attack the rock working face 140 with an undercutting action. In the context of the present disclosure, the term "semi-tangential" may comprise a range of up to 30 degrees to a purely tangential direction, preferably 22 to 28 degrees, more preferably 24 to 26 degrees, such as about 25 degrees.
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The arm 122 may be configured to pivot or slew about the primary pivot axis A1 from the retracted position a first angle B1 being at least 90 degrees between the retracted position and the advanced position, preferably at least 100 degrees, more preferably at least 108 degrees, as shown in FIG. 2B, FIG. 3 and FIG. 7.
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Due to the generally circular shape of the cutterhead(s) periphery formed by the plurality of roller cutters 130, a shape of the rock working face 140 may as a result of the first cutting movement A11 and/or the fourth cutting movement A11' comprise crests separated by valleys, as derivable for example from FIG. 3. Of course, it may be preferable to facilitate a more leveled or more even floor of the tunnel. To this end, one or more floor-clearing cutting movements may be of benefit, such as one or more of angular movements A31, A21, A32, A22, as will be further elucidated herein.
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The tertiary pivot axis A3 facilitates floor-clearing cutting movements. The tertiary pivot axis A3 may be at the center of the turret 124. A respective cutterhead rotational axis A4, A4' is disposed displaced from the center of the turret 124 i.e. displaced from the tertiary pivot axis A3, whereby rotation of the turret 124 translates to the cutterhead rotations axis A4 being displaced arcuately, such as in a curvilinear motion, about the tertiary pivot axis A3.
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In some embodiments the pivot coupling 118 is configured to swing or pivot the support 120 about the secondary pivot axis A2 a second angle B2 corresponding to at least +/- 20 degrees, that is B2 being at least 40 degrees, preferably at least +/- 26 degrees relative to the machine direction X, that is B2 being at least 52 degrees as shown in FIG. 2C, FIG. 6 and FIG. 10.
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The turret 124 may be configured to swivel or rotate or pivot the cutterhead(s) about the tertiary pivot axis A3 a third angle B3 corresponding to at least +/- 30 degrees, that is B3 being at least 60 degrees, preferably at least +/- 37 degrees, that is B3 being at least 74 degrees. FIG. 2d, FIG. 5, FIG. 9.
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A respective roller cutter rotational axis A5, A5' forms with a respective cutterhead rotational axis A4, A4' a fourth angle B4 that is in the range of 60 to 90 degrees, preferably 70 to 80 degrees, as schematically illustrated in FIG. 2A. Thus, the roller cutter rotational axes A5, A5' of the plurality of roller cutters 130 of a respective cutterhead 128, 128' may in some embodiments form a conical shape that one or more of tapers in the forward direction of the machine and has a base proximal to the cutterhead housing and/or turret.
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Referring to FIG. 3 to FIG. 13 there is illustrated embodiments of a cutting method 200 for a rock cutting machine, which may be rock cutting machine 100 according to embodiments of the disclosure.
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The rock cutting machine 100 comprises a main frame 102 having a machine direction X orthogonal a main frame vertical extension Y and a main frame lateral Z extension, and one or more frontal cutterheads 128, 128' rotatable about a respective cutterhead rotational axis A4, A4' arranged along a cutting direction C as seen in a horizontal plane XZ.
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At S202 the method may comprise setting S202 a respective rotational axis A4, A4' along, such as parallel, a first cutting direction C1 in a horizontal plane XZ.
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At S204 the method may comprise rotating S204 a respective cutterhead 128, 128' about its respective rotational axis A4, A4'. The cutterhead(s) may be rotated in opposite directions as shown in FIG. 2A.
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Referring to FIG.3 and FIG.4, at S206 the method 200 may comprise performing a first cutting movement S206A by a first angular motion A11 of the cutterhead(s) 128, 128' in a vertical plane XY, such as a curvilinear motion that may be directed upwards, in the first cutting direction C1, and preferably performing a corresponding opposite retracting movement S206B by a second opposite angular motion A12.
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Referring to FIG. 5 and FIG. 9, at S208 the method may comprise adjusting S208 the cutting direction C. Adjusting S208 the cutting direction C may comprise adjusting S208 by displacing the cutterhead(s) 128, 128' along the horizontal plane XZ, such as by one or more second angular motion A31 and/or a fifth angular motion A32 of the cutterhead(s) about a tertiary pivot axis, which may be distal pivot axis A3 relative to the frame 102.
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Referring to FIG. 5, at S208 the method 200 may comprise performing a second cutting movement S208A by a second angular motion A31, that may be a curvilinear motion A31, of the cutterhead(s) 128, 128' about the tertiary pivot axis A3 with the cutterhead rotational axes A4, A4' generally oriented parallel a horizontal plane XZ. As shown in FIG. 5, the second angular motion A31 rotates the cutterhead rotational axes laterally towards the left as seen in the machine direction X. The second cutting movement may result in the floor of the tunnel being more even. Thus, the second cutting movement may be a floor-clearing cutting movement in the sense that the floor 140b of the tunnel is rendered more even.
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As shown in FIG. 6 and FIG. 10, adjusting S210, S216 the cutting direction C may comprise adjusting S210 by displacing the cutterhead(s) 128, 128' along the horizontal plane XZ, such as by an angular motion, which may be a curvilinear motion, of the support, in particular the cutterheads, about a secondary pivot axis A2, which may be proximal relative to the frame 102 in relation to the tertiary pivot axis A3.
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Adjusting S210, S216 may comprise a third angular motion A21 and an opposite sixth angular motion A22 of the cutterhead(s) 128, 128' laterally Z along the horizontal plane XZ, such as about the secondary pivot axis A2 relative the frame 102.
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Put differently, at S210, S216 the method may comprise adjusting one or more of the cutting direction C and a lateral Z position of the cutterhead(s) 128, 128' along the horizontal plane XZ by one of a third angular motion A21 and an opposite sixth angular motion A22 of the cutterhead(s) 128, 128' about a secondary pivot axis A2 that is proximal to the main frame.
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It should be appreciated that the cutterhead(s) may be rotated or not rotated whilst performing any of the adjusting steps of S208, S210, S214, S216.
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Hence, at S210 the method 200 may comprise performing a third cutting movement S210A by an angular motion, such as by the third angular motion A21, that may be a curvilinear motion, of the cutterhead(s) 128, 128', such as about the secondary pivot axis A2, preferably with the cutterhead(s) 128, 128' rotational axes A4, A4' generally oriented parallel the horizontal plane XZ. As shown in FIG. 6, the third angular motion A21 pivots the support 120 including the arm 122 and the cutterhead rotational axes towards the left-hand side of the machine 100 as seen in the machine direction X. The third cutting movement may result in the floor of the tunnel being more even. Thus, the third cutting movement may be a floor-clearing cutting movement in the sense that the floor 140b of the tunnel is rendered more even.
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Referring to FIG. 7 and FIG. 8, at S212 the method may comprise performing a fourth cutting movement S212 in a second cutting direction C2 different from the first cutting direction C1, such as by a corresponding first angular motion A11' of the cutterhead(s) 128 in a vertical plane XY, and preferably an opposite retracting movement by a corresponding opposite second angular motion A12'.
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Referring to FIG. 9, at S220 the method 200 may comprise performing a fifth cutting movement S214A by a fifth angular motion A32, such as oppositely directed the second angular motion A31, that may be a curvilinear motion, about the tertiary pivot axis A3 with the cutterhead rotational axes A4, A4' generally oriented parallel a horizontal plane XZ. As shown in FIG. 9, the second angular motion A31 rotates the cutterhead rotational axes laterally towards the right as seen in the machine direction X. The fifth cutting movement may result in the floor of the tunnel being more even. Thus, the fifth cutting movement may be a floor-clearing cutting movement in the sense that the floor 140b of the tunnel is rendered more even.
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Likewise, referring to FIG. 10, at S216 the method 200 may comprise performing a fourth cutting movement S216A by an angular motion, such as a sixth angular motion A22, that may be oppositely directed the fourth third motion A21. The sixth angular motion may be a curvilinear motion of the cutterhead(s) 128, 128', such as about the secondary pivot axis A2, preferably with the cutterhead rotational axes A4, A4' generally oriented parallel the horizontal plane XZ. As shown in FIG. 10, the sixth angular motion A22 pivots the support 120 including the arm 122 and the cutterhead rotational axes towards the right-hand side of the machine 100 as seen in the machine direction X. The sixth cutting movement may result in the floor of the tunnel being more even. Thus, the sixth cutting movement may be a floor-clearing cutting movement in the sense that the floor 140b of the tunnel is rendered more even.
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In an exemplary embodiment of the disclosure, a cutting cycle may comprise performing steps of the method 200 in the following sequence: performing the first cutting movement S206 at least by the first angular movement A11, performing the second cutting S208A movement, such as by the second angular motion A31, performing the third cutting movement S210A, such as by the third angular motion A21, performing the fourth cutting movement S212, such as at least by the fourth angular motion A11', performing the fifth cutting movement S214A, such as by the fifth angular motion A32, performing the sixth cutting movement S216A, such as by the sixth angular motion A22.
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Referring again to FIG. 1 and FIG. 2, a detachable control unit 101 is mounted to the frame rearward end 403 via a pivot coupling 200. Control unit 111 comprises a personnel cabin (to be occupied by an operator). Unit 111 further comprises an electric and hydraulic power pack 114 to control the various hydraulic and electrical components of machine 100 associated with the pivoting movement of the support 120 and arm 122 in addition to the sliding movement of sled 104 and the rotational drive of cutterheads 128, 128'.
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Control unit 101 further comprises a second conveyor 112 extending generally lengthwise along the unit 101 and coupled at its forwardmost end to the rearwardmost end of first conveyor 202. Unit 101 further comprises a discharge conveyor 113 projecting rearwardly from the rearward end of second conveyor 112 at an upward declined angle. Accordingly, cut material is capable of being transported rearwardly from cutterheads 128, 128' along conveyors 202, 112 and 113 to be received by a truck or other transportation vehicle.
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In use, machine 100 is wedged between the tunnel floor and roof via jacking legs 106, 115 and roof grippers 105. Sled 104 may then be displaced in a forward direction relative to main frame 102 to engage roller cutters 130 onto the rock face. Cutterheads 128 are rotated via motors 125 that create the initial groove or channel in the rock face at a lowermost position.
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When the maximum forward travel of sled 104 is achieved, jacking legs 106, 115 are retracted to engage tracks 103 onto the ground.
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The machine 100 may then be advanced forward via tracks 103. Jacking legs 106, 115 may then be actuated again to raise tracks 103 off the grounds and grippers 105, 108 moved into contact with the tunnel roof to repeat the cutting cycle. A forwardmost roof gripper 108 is mounted above sled 104 to stabilise the machine 100 when sled 104 is advanced in the forward direction via linear actuating cylinder 201.
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It should be appreciated that expressions like "substantially [feature]" or "generally [feature]", as used in the context of the disclosure, for example in a setting like "generally horizontal" or "substantially perpendicular", are used for ease of conveying the invention and should not be understood as limiting the invention to a strict literal interpretation or meaning. As such, "substantially or generally [feature]" may comprise "including, not limited to [feature]". In some embodiments, any of a substantially or generally parallel, transverse, perpendicular, horizontal or vertical arrangement may be quantified as comprising and/or encompassing a deviation of +/- 20 degrees, preferably less than +/- 10 degrees from such feature, unless indicated otherwise. For example, "substantially perpendicular" may be quantified as 90 degrees +/- up to 20 degrees or up to 10 degrees. "Distal" refers to "away from the main frame along the machine direction, or away from a pivot axis".