WO2015079418A2

WO2015079418A2 - Mining apparatus

Info

Publication number: WO2015079418A2
Application number: PCT/IB2014/066423
Authority: WO
Inventors: Nicolaas Daniel Lombard Burger; Stefan MYBURG; Jan Stephanus OOSTHUIZEN
Original assignee: Nicolaas Daniel Lombard Burger
Priority date: 2013-11-28
Filing date: 2014-11-28
Publication date: 2015-06-04
Also published as: ZA201606954B; ZA201606956B; WO2015079418A3

Abstract

This invention relates to a mining apparatus 10. The apparatus 10 includes a vehicle chassis 12 and a plurality of steerable continuous rubber track assemblies 14 mounted on the chassis 12 for propelling the apparatus 10. Each track assembly 14 has a pair of first planar or flat ground engaging surfaces 26 and an opposing pair of second planar or flat ground engaging surfaces 28. As a result of the track assembly 14 being pivotally displaceable, the first and second surfaces 26 and 28 could respectively be brought into contact with the ground 29. Therefore, by pivotally adjusting the track assembly 14 between having either the first or second contact surface 26 or 28 in contact with the ground 29, the height of the chassis 12 above the ground 29 could be adjusted.

Description

MINING APPARATUS

FIELD OF THE INVENTION This invention relates to a mining apparatus. More particularly, but not exclusively, this invention relates to a mining apparatus for working in an underground mine stope, especially on a work face in low stoping height underground hard rock mines. The invention also extends to a method of working on a rock face. BACKGROUND TO THE INVENTION

It is well known in the underground hard rock mining industry to make use of either pneumatic, hydraulic or electrical drills for drilling and breaking mining work faces. A wide variety of these drills are available on the market. All of these drills work on the basic principle of having a rotating drill bit which is driven by an impact drifter. Such type of drill is commonly referred to as a drifter drill. In especially low seam heights these drills are still predominantly manually operated by humans. As a result, the operators of these devices are continually subjected to noise levels in excess of 1 10 dB as well as inhaling dust and exhaust fumes originating from the drill action. This inhalation of dust is a major cause of silicosis. These operators are also subjected to the continuous risk of rock falls where loose rock can be dislodged from the hanging wall. Currently, this is still the biggest cause of fatalities and lost work time in underground mine workings. In order to at least partially address the above difficulties, there has been a mayor drive to mechanise the rock drilling process and a variety of these machines are currently available on the market. Typically, these machines can be either remote controlled with stand-off controls wherein the operator is positioned a distance away from the machine, or directly controlled by the operator standing next to the machine. Further, these machines are movable by either being mounted on four or more rubber wheels to propel the machine, or by being mounted on top of pre-installed running gear on which they can move. Such machines known in the art are not fitted with mechanical rock breakers and therefore the standard technique is to drill a hole and then to perform blasting operations to break the rock. It is well known that blasting is associated with a number of negative side effects such as that it introduces cracks in the hanging wall, which could result in the fall of ground, it gives rise to water pollution with the by- products from the blasting, namely SO_x and NO_x, and it results in the dilution of minerals.

A further problem with the type of machines referred to above, is that they are bulky and their overall height make them impossible to be used in ultra low stoping height underground hard rock mines. These machines also struggle to navigate over uneven terrain and loose under foot conditions, and to handle inclines or declines in excess of twenty five degrees. These machines are furthermore unable to adjust their chassis height from the ground and still be able to operate normally, including negating difficult terrain and working on a work face at the adjusted height. A further shortcoming with these types of machines known in the art, is that they are positioned on their wheels when they perform drilling operations. This is not desirable since all vibrations generated as a result of drilling are transmitted through the machine to its wheels, thus unnecessarily subjecting the control components to adverse reaction load vibrations.

Mobile drilling machines are furthermore not able to have their chassis properly remain in a stationary position whilst performing a plurality of successive drilling operations on a mining work face. This makes it very difficult for the machine to perform a predetermined set of drillings accurately as it easily looses its reference point on the wall between successive drillings.

It is thus evident that these machines are especially not feasible for use in old workings, predominantly as a result of their lack of manoeuvrability and ground clearance, and also as a result of other shortcomings highlighted above. In some of these old workings the typical area that is available for a machine to work in is less than 1 .5 metres, as this is the distance which the supports are spaced from each other. It is further known to the applicant that other types of machines which are not necessarily used in underground mining operations, but could include same, and have a plurality of steerable continuous track assemblies mounted on the chassis for propelling and steering the machine, employ positioning sensors to determine the orientation or tilt of the track assemblies relative to the axis about which they are propelled. Such positioning sensors are very expensive and desirable for when the machine is used in harsh conditions.

In the context of this specification, the terms 'underground mine' and 'stope' are to be construed broadly to include other subterranean excavations such as tunnelling and the like. Further in the context of this specification, the term 'mining' is to be constructed broadly to include other excavations such as earth moving and the like.

OBJECT OF THE INVENTION

It is accordingly an object of the present invention to provide a mining apparatus that will, at least partially, alleviate the abovementioned problems and/or to provide a mining apparatus that will be a useful alternative to known mining apparatuses. SUMMARY OF THE INVENTION

According to a first aspect of the invention, there is provided a mining apparatus comprising a vehicle chassis and a plurality of continuous track assemblies mounted on the chassis for propelling the apparatus, each track assembly having first and second ground engaging surfaces which respectively causes the chassis to be a first distance from the ground when the first ground engaging surface is in contact with the ground and causes the chassis to a second distance from the ground when the second ground engaging surface is in contact with the ground. Each track assembly may be pivotally displaceable such to respectively bring the first and second ground engaging surfaces into contact with the ground. The pivotal displacement may be about a drive axis and in an operatively vertical plane. The second distance may be greater than the first distance.

According to an example embodiment of the invention, a perpendicular distance between a drive axis and the second ground engaging surface may be greater than a perpendicular distance between the drive axis and the first ground engaging surface.

There is provided for the ground engaging surfaces to be a planar ground engaging surfaces. Each track assembly may include a continuous track member, at least one drive wheel engaging the continuous track member to drive the track assembly and a plurality of idler wheels engaging the continuous track member for retaining the continuous track member in a desired shape. The track assembly may be driven in a clockwise or anticlockwise direction by means of a first permanent-magnet synchronous motor.

The first and second ground engaging surfaces may respectively extend between two wheels. There is provided for each continuous track assembly to include a pair of first ground engaging surfaces running surfaces located adjacent each other and a pair of second ground engaging surfaces located adjacent each other, with the respective pairs opposing each other.

Each of the track assemblies may be shaped in the form of a parallelogram, in plan view.

The plurality of continuous track assemblies may be steerable in that they are pivotally movable relative to the vehicle chassis about an operatively vertical axis.

According to an example embodiment of the invention, the apparatus may include a tool supporting arrangement positioned on the vehicle chassis and a first tool supported on the tool supporting arrangement for carrying out work on a rock face.

The apparatus may also include a second tool supported on the tool supporting arrangement for carrying out work on the rock face.

The first tool may comprise a drill and the second tool may comprise a mechanical rock breaker.

According to a second aspect of the invention, there is provided a mining apparatus comprising:

- a vehicle chassis supporting a first tool for carrying out work on a rock face; and - stabilizing means for abutting and stabilizing the apparatus against a support surface whilst the first tool is carrying out work on the rock face.

There is provided for the support surface to be any one or more of a side wall, a hanging wall and a foot wall. According to at least some embodiments of the invention the side wall may be the rock face.

According to an example embodiment of the invention, the stabilizing means may include an abutting member for abutting against the rock face adjacent to where the first tool is to carry out work.

The apparatus may include a tool supporting arrangement positioned on the vehicle chassis and having a tool carriage for supporting the tool, with the abutting member being located on an end of the tool carriage.

The abutting member may be a resilient body which prevents the first tool from slipping, in use.

According to a further example embodiment of the invention, the stabilizing means may include a first stabilizing assembly having a first extendible member for abutting against the hanging wall. The first stabilizing assembly may also have a second extendible member for abutting against the foot wall to thus anchor the apparatus between the hanging and foot walls. The first and second extendible members may be a pair of cylinders which are telescopically extendible in opposing directions. According to an example embodiment of the invention, the stabilizing means may further include a second stabilizing assembly which is similar to the first stabilizing assembly, the first and second stabilizing assemblies being spaced along the length of the apparatus and respectively located towards front and rear ends of the apparatus.

According to a third aspect of the invention, there is provided a mining apparatus comprising a vehicle chassis supporting first and second tools for carrying out work on a rock face when they are respectively located in an operative position, the tools being laterally displaceable such to be interchangeable in the operative position.

The tools may be laterally displaceable by being mounted on a tool support and displaceable along a length of the tool support. The tools may be displaceable on the tool support by means of at least one tool support actuator.

There is further provided for the tools to be axially displaceable which is, in use, in a direction towards and from the rock face.

The tools may be axially displaceable by the tool support being mounted on a tool carriage which is displaceable along a length of the tool carriage on carriage tracks.

The tool support and tool carriage may form part of a tool supporting arrangement which is positioned on the vehicle chassis, the tool supporting arrangement including a telescopically extendible arm which is secured at its first end on the vehicle chassis and supports the tool carriage and tool support at an opposing second end. The first tool may be a drill and the second tool may be a mechanical rock breaker.

According to a fourth aspect of the invention, there is provided a method of working on a rock face including the steps of:

- providing a mobile mining apparatus having a drill and a mechanical breaker for carrying out work on a rock face;

- orientation the drill to a preferred orientation relative to the rock face;

- drilling a hole in the rock face with the drill;

- moving the drill out of alignment with the hole;

- moving the mechanical breaker in line with the hole; and

- fracturing the hole with the mechanical breaker.

There is provided for the apparatus to remain in position whilst the drill is moved out of alignment and the mechanical breaker is moved in line with the hole.

There is further provided for the apparatus to remain in position whist orientating the drill to the preferred orientation.

The method may further include the step of stabilizing the apparatus against a support surface before and during the drill and mechanical breaker is carrying out work on the rock face.

There is provided for the support surface to be any one or more of a side wall, a hanging wall and a foot wall. According to at least some embodiments of the invention the side wall may be the rock face. The step of orientating the drill to a preferred orientation may any one or more of the further steps:

- pivotally moving the drill about an x-axis;

- pivotally moving the drill about a y-axis;

- pivotally moving the drill about a z-axis;

- laterally moving the drill along an x-axis;

- laterally moving the drill along the y-axis,

- laterally moving the drill along a z-axis;

- the X-, y- and z-axes being orthogonal to each other.

According to a fifth aspect of the invention, there is provided a method of adjusting the orientation of a continuous track assembly relative to the ground, the method including the steps of:

- providing a continuous track assembly having a ground engaging surface and a motor for pivotally displacing the ground engaging surface about a pivoting axis relative to the ground;

- providing a reference input current to the motor for maintaining the ground engaging surface in a predetermined orientation relative to the ground; and

- adjusting the orientation of the ground engaging surface when the input current required to maintain the ground engaging surface in the predetermined orientation relative to the ground deviates from the reference input current.

The method may include the further step of pivotally displacing the ground engaging surface upwards when the input current is greater than the reference input current. The method may further include the step of pivotally displacing the ground engaging surface downwards when the input current is less than the reference input current.

The predetermined orientation may be a neutral orientation, more particularly a horizontal orientation.

The may also include the step of calculating the reference input current when the ground engaging surface is in the predetermined orientation relative to the ground. The ground engaging surface may be a planar ground engaging surface.

These and other features of the invention are described in more detail below.

BRIEF DESCRIPTION OF THE DRAWINGS

One embodiment of the invention is described below, by way of a non-limiting example only and with reference to the accompanying drawings in which:

Figure 1 is a schematic front perspective view from above of a mining apparatus in accordance with the invention;

Figure 2 is a schematic rear perspective view from above of the apparatus of figure 1 ; Figure 3 is a schematic side view of the apparatus of figure 1 ; Figure 4 is a schematic top view of the apparatus of figure 1 ; is a schematic detail view of part of the apparatus of figure 1 ; is a schematic plan view of a track assembly of the apparatus, illustrating it in different positions; is an operational flow diagram showing a selection of inputs which a local controller receives to control the apparatus; and is an operation flow diagram followed to adjust the orientation of a continuous track assembly relative to the ground.

DETAILED DESCRIPTION OF THE INVENTION

With reference to the drawings, a mining apparatus in accordance with the invention is generally indicated by reference numeral 10.

The apparatus 10 includes a vehicle chassis 12 and a plurality of steerable continuous rubber track assemblies 14 mounted on the chassis 12 for propelling the apparatus 10 over difficult terrain. The track assemblies 14 are pivotally movable A (see figure 4) relative to the chassis 12 about a first axis V, which is an operatively vertical axis, as shown in figure 1 . There are four continuous track assemblies 14 which are arranged in front and rear pairs. The track assemblies 14 could be driven and steered independent from, or in synchronization with each other. This allows for the apparatus 10 to perform a steering operation, generally known as crab steering, wherein front and rear pairs of the track assemblies 14 could be turned simultaneously at different angles relative to the vehicle chassis 12. It is especially useful to navigate around tight corners and to move the apparatus 10 closer to and further from a rock or work face on which the apparatus 10 needs to carry out work. According to the embodiment shown, all the continuous track assemblies 14 are similar and hence they will be further described herein with reference to only one continuous track assembly 14, unless where it appears to the contrary.

Referring particularly to figures 6a and 6b, the track assembly 14 comprises a drive wheel 16, a plurality of idler wheels 18 and a continuous rubber band 20 extending around and engaging the wheels 16 and 18. Collectively, the wheels 16 and 18 hold the band 20 into a desired shape, which is substantially a parallelogram in plan view in this embodiment. The drive wheel 16 is connected to a first permanent-magnet synchronous motor 22 (see figures 1 to 4). The first motor 22 provides traction through a reduction gearbox (not shown) allowing the continuous track assembly 14 to be driven clockwise or anticlockwise. The drive wheel 16 is also connected to a second permanent-magnet synchronous motor 24 (see figures 1 to 4) which enables the track assembly 14 to be rotated or pivotally displaceable B (see figure 3) relative to the vehicle chassis 12 about a second or drive axis W which is an operatively horizontal axis, as shown in figure 1 . The track assembly 14 is thus pivotally displaceable in an operatively vertical plane, with the first and drive axes V and W being orthogonal to each other. Still referring to figures 6a and 6b, the track assembly 14 has a pair of first planar or flat ground engaging surfaces 26 and an opposing pair of second planar or flat ground engaging surfaces 28. The first surfaces 26 are located adjacent each other and the second surfaces 28 are also located adjacent each other. Each of the first and second surfaces 26 and 28 extend between two wheels, being either the drive wheel 16 and an idler wheel 18, or two idler wheels 18.

A first perpendicular distance C between the drive axis W and the first surface 26 is smaller than a second perpendicular distance D between the drive axis W and the second surface 28. As a result of the track assembly 14 being pivotally displaceable, the first and second surfaces 26 and 28 could respectively be brought into contact with the ground 29. Therefore, by pivotally adjusting the track assembly 14 between having either the first or second contact surface 26 or 28 in contact with the ground 29, the height of the chassis 12 above the ground 29 could be adjusted. In figure 6a, it is shown that the first surface 26 is in contact with the ground in which case the chassis 12 would be a first distance from the ground 29. In figure 6b, it is illustrated that the second surface 28 is in contact with the ground 29 in which case the chassis 12 would be a second distance from the ground, resulting in the chassis 12 being higher.

It should be appreciated that a planar ground engaging or running surface abutting the ground 29 is desirable in that it is stable, ensures good load bearing characteristics and a machine can easily operate for extended periods in such a position. The weight of the vehicle is also distributed equally amongst the tracks, ensuring good traction. For example, it is more desirable than having a track assembly orientated such that only an end or tip thereof is in contact with the ground, which is generally referred to as 'standing on a toe'. Generally, a machine will only stand on ends of its track assemblies for short periods, such as for negating large obstacles, thereafter reverting back to its normal operating height.

By the track assembly 14 having two distinct ground engaging surfaces 26 and 28, the apparatus 10 is able to easily and accurately perform work on a rock face whilst the chassis 12 being on either of two heights above the ground, creating a bigger operating envelope regarding stoping height. The apparatus 10 are also able to easily clear obstacles (not shown), where the obstacles are not higher than the length of the track assemblies 14. The displacement B also provides the apparatus 10 with the capability of adjusting its centre of gravity, aiding the apparatus 10 to easily negate hostile inclines, declines and loose under foot conditions. As stated above, the track assembly is displaceable B by means of the second motor 24 which is carried out in accordance with the invention by adjusting an input current to the second motor 24. Should the track assembly 14 during movement encounter an object or obstacle (not shown) such as, for example, a rock, bump, boulder, hollow, incline decline, and the like, it is important for the track assembly 14 to displace B accordingly, to have the surface in use, being either 26 or 28 facing the obstacle. Such displacement B is carried out automatically by measuring the input current to the second motor 24 to hold it in position and comparing it to a reference input current. Referring particularly to figure 8, the reference input current is generally set 30 by measuring the input current to the second motor 24 when the apparatus 10 is positioned on a substantially horizontal flat terrain or surface. The reference input current is thus the current which is required to retain the track assembly 14 in position, since there is a moment on the drive axis W, even when the apparatus 10 is stationary.

During movement, the input current is continuously measured 32. When the track assembly 14 encounters and makes contact with, for example, a rise in the ground level or an object, the moment on the drive axis W increases which results in an increase in the input current to the second motor 24. The input current is no longer in balance 34 with the reference input current as a result of it being higher 36. Accordingly, the track assembly 14 is adjusted B or tilted upwards 38. Similarly, when the track assembly 14 encounters and makes contact with, for example, a declining or downward orientating ground level, the moment on the drive axis W decreases which results in a decrease in the input current to the second motor 24. The input current is no longer in balance 34 with the reference input current as a result of it being lower 40. Accordingly, the track assembly 14 is adjusted B or tilted downwards 42.

It should be appreciated that the measurement 32 and automatic displacement B described above are carried out and repeated on a continuous basis and is typically performed by a local on-board controller. The apparatus 10 further includes a tool supporting arrangement 44 positioned on the chassis 12. The supporting arrangement 44 consists of an arm 46 or boom, a tool carriage 48 and a tool support 50 or sledge. The arm 46 is pivotally supported on the chassis 12 at a first end 52 thereof and holds the tool carriage 48 and tool support 50 at a second end 54 thereof. The arm 46 is telescopically extendible E (see figure 3) to increase its length and to allow for further reach of its second end 54 from the chassis 12. Further, the arm 46, is pivotally displaceable F (see figure 3) between a lower position (as shown in the figures) in which it extends horizontally and an angularly displaced or tilted position (not shown) in which it extends at an angle relative to the ground. A first arm actuator 56 in the form of a slew drive enables the extension E and a second arm actuator 58 in the form of a slew drive and enables the pivotal displacement F. As shown, the second arm actuator 58 is connected to the arm 46 intermediate its first and opposing second end regions 52 and 54.

Referring particularly to figures 3 and 4, the tool carriage 48 is connected to the arm 46 in such a manner that it is pivotally moveable (or rotatable) about x-, y- and z- axes of the Cartesian diagram shown in these drawings, by means of a plurality of joints or knuckles. More particularly, the tool carriage 48 is pivotally movable G about the z-axis, pivotally movable H about the x-axis and pivotally movable J about the y- axis.

Turning to figure 5, it is shown that the tool carriage 48 is supported on a lifting mechanism 60 to displace K the carriage 48 along the y-axis. It should be appreciated that the lifting mechanism 60 could take any form, including hydraulically operated, rack and pinion arrangement, and the like.

A first tool in the form of a drill 62 and a second tool in the form of a mechanical breaker 64 are mounted on the tool support 50 as is best shown in the detail view of figure 5. The tools 62 and 64 are therefore also able to pivotally rotate about x-, y- and z-axes in the manner described above. Preferably, the drill 62 is hydraulically driven and the rock breaker 64 is either electrically or hydraulically driven. The term "hydraulic" as used in this specification is to be construed to include any suitable liquid, such as a liquid selectable from a group comprising water and hydraulic oil.

The tool support 50 is slidably mounted on carriage tracks 66 of the carriage 48 such to be movable L along the z-axis along the length of the carriage 48 by means of at least one hydraulically operated tool carriage actuator or cylinder. The tools 62 and 64 are therefore, in use, able to displace axially to and from the rock face to carry out work. The tools 62 and 64 are furthermore able to displace M laterally on an along the length of the tool support 50 along the x-axis by means of a hydraulically operated tool support actuator 68 or cylinder. The tools 62 and 64 are therefore, in use, able to displace laterally along the rock face to carry out work. This enables the tools 62 and 64 to be interchangeable in an operative position, wherein the tools 62 and 64 respectively carry out work on the rock face when in this position. In figures 1 to 5, the drill 62 is shown to be in the operative position, and it should be appreciated that the drill 62 could move laterally out of this position along the z-as, with the mechanical breaker 62 taking its position on the support 50. As is best shown in figure 2, the apparatus 10 further includes first stabilizing means, being an abutting member 70 in the form of a resilient body or pad. The abutting member 70 is located at a free end of the carriage 48 which, in use, abuts against the rock face adjacent to where the tools 62 and 64 are to carry out work on the rock face. The abutting member 70 stabilizes the apparatus 10 against the rock face, being a support side wall, and prevents the tools 62 and 64 from slipping, in use. A further important function which the abutting member 70 performs is to retain a reference position or point on the work face whilst the tools 62 and 64 are carrying out work, which enables the tools 62 and 64 to easily switch between the operative position to carry out work at the exact same position on the work face.

The apparatus 10 yet further includes second stabilizing means, comprising first and second stabilizing assemblies 72 and 74. The stabilizing assemblies 72 and 74 are spaced apart along the length of the apparatus 10 with the first assembly 72 being located towards a rear end of the apparatus 10 and the second assembly 74 being located towards a front end of the apparatus 10. The assemblies 72 and 74 are similar with each respectively including first or upper telescopically extendible members 76 and second or lower extendible members 78. In use in underground mining, the upper extendible members 76 are extendible N towards a hanging wall (not shown) for engaging the hanging wall and the lower extendible members 78 are extendible N in an opposing direction towards a foot wall (ground) for engaging the foot wall. The hanging and foot walls are support surfaces. The lower extendible member 78 of the first stabilizing assembly is retracted into the chassis 12 and thus not visible in the drawings. Gripping formations 80 on the extendible members 76 and 78 enhance secure gripping on support surfaces. The second assemblies 72 and 74 therefore stabilize and anchor the apparatus 10 against and between the hanging and foot walls. The second assemblies 72 and 74 further enable the chassis 12 to lift from the ground and self centre and thus float between the hanging and foot walls which, during use, enables a significant amount of the reaction load vibrations of the drill and breaker 62 and 64 to be conveyed directly from the tools 62 and 64 to the assemblies 72 and 74 and not through the apparatus to the track assemblies 14. This ensures that the generally sensitive control components (not shown) of the apparatus 10 are protected from being subjected to unnecessary adverse reaction load vibrations.

When the apparatus 10 is used in underground mining, the operator would move the apparatus 10 to a desired location in the mine stope where the apparatus 10 is to carry out work on the rock face. This, and any other instructions the apparatus 10 requires, is received from a stand-off remote control (not shown) which is under the control of the operator. The stabilizing assemblies 72 and 74 would then be extended until they engage with the hanging and foot walls to secure the apparatus 10 in position. Next, the arm 46, carriage 48 and support 50 are orientated and moved, as described above, to position the drill 62 in a desired position and orientation. The abutting member 70 also now engages the rock face. All of this would occur whilst the apparatus 10 remains in position.

With the drill 62 in its operative position, it is activated and a hole is drilled in the rock face. The drill 62 is then moved out of alignment with the drilled hole and its place is taken by the mechanical breaker 64 which is subsequently in the operative position, being aligned with the hole. The breaker 64 could now fracture the hole. All of this would occur whilst the apparatus 10 remains in position.

Although not shown, there are various components installed within a vehicle housing 82 which perform an integral function in the performance of the apparatus 10. It should be appreciated that not all of these components have to be present and one or more of them could be omitted from various embodiments of the invention. A transceiver is provided for receiving an input signal from a remote station such as a remote control, and transmitting a feedback signal to the remote station. The remote station could be operated by an operator to provide instructions to the apparatus 10 from a remote location. One type of feedback received at the remote station is visual feedback provided by means of one or more cameras mounted on the apparatus 10. Distance measurement sensors also provide feedback as to the distance of the apparatus 10 from an object, wall, or the like and/or the height of the chassis 12 and/or track assemblies 14 from the ground. Further, an inclinometer is provided with which the apparatus 10 is able to determine its inclination and self adjust its inclination to a desired inclination. Still further, an electrically driven hydraulic pump is provided for providing all hydraulic power to the apparatus 10. It should be appreciated that the hydraulic pump could be omitted in cases where water already in a high pressure state is supplied to the apparatus 10 resulting in the saving of weight of the apparatus 10. Typically, water is supplied at between 16 - 18 MPA. Yet further, a central lubricating system supplies lubrication to the drill 62 and rock breaker 64. Now referring particularly to figure 7, it is shown that a local controller 84 receives one or more of a selection of different inputs 86 in order to successfully control 88 the apparatus 10. The only inputs 86 which are received from the remote station, is the positioning of the apparatus 10 and instructions to commence operation. The remaining inputs 86 are communicated to the local controller 84 by means of a selection of sensors. The control 88 of the apparatus 10 is generated in response to the inputs 86 and also by means of pre-programmed instructions. The local controller 84 permits the tools 62 and 64 to perform a sequence of intelligent automated operations after receiving an initial input signal from the remote device. For example, once the apparatus 10 is correctly positioned to drill a first hole, the local controller permits 84 for a subsequent amount of holes to be drilled without requiring the intervention of the operator. Preferably, the subsequent amount of holes is six. The local controller 84 allows for a number of holes to be drilled one after the other without requiring the assistance of the operator.

The overall height of the apparatus 10 is less than 900 mm, it can work in stopes as high as 1 .6 metres and it can carry a payload load of at least 900 kg.

It is envisaged that the apparatus 10 disclosed herein is compact in design and easy to manoeuvre over uneven terrain and loose underfoot conditions, making it convenient for use in low stoping height underground hard rock mines. It is also envisaged that an operator of the apparatus 10 does not have to be exposed to excessive noise levels, inhaling of dust and rock falls as the apparatus 10 can be operated from a safe distance by means of a remote control, typically by die operator standing in the gulley of a mine shaft, i.e. a distance away from where the apparatus 10 is in operation. Further, it is not necessary to make use of blasting as the apparatus 10 is equipped with both a drill 62 and a rock breaker 64.

It will be appreciated by those skilled in the art that the invention is not limited to the precise details as described herein and that many variations are possible without departing from the scope and spirit of the invention. For example, the continuous rubber bands 20 could include gripping elements (not shown) on their respective outer surfaces. Further, at least some of the hydraulic operated components referred to above could be replaced by pneumatic operated components.

It will further be appreciated that the foregoing example has been provided merely for the purposes of explanation and is in no way to be construed as limiting of the present invention. While the present invention has been described with reference to an exemplary embodiment only, it is understood that the words which have been used herein are words of description and illustration, rather than words of limitation. The present invention is also not intended to be limited to the particulars disclosed herein. Rather, the present invention extends to all functionally equivalent structures, methods and uses, such as are within the scope of the appended claims.

Claims

A mining apparatus comprising a vehicle chassis and a plurality of continuous track assemblies mounted on the chassis for propelling the apparatus, each track assembly having first and second ground engaging surfaces which respectively causes the chassis to be a first distance from the ground when the first ground engaging surface is in contact with the ground and causes the chassis to a second distance from the ground when the second ground engaging surface is in contact with the ground.

The mining apparatus according to claim 1 , wherein each track assembly is pivotally displaceable such to respectively bring the first and second ground engaging surfaces into contact with the ground.

The mining apparatus according to claim 2, wherein the pivotal displacement is about a drive axis and in an operatively vertical plane.

The mining apparatus according to any one of the previous claims, wherein the second distance is greater than the first distance.

The mining apparatus according to claim 1 , wherein a first perpendicular distance between a drive axis and the second ground engaging surface is greater than a second perpendicular distance between the drive axis and the first ground engaging surface. The mining apparatus according to any one of the preceding claims, wherein the ground engaging surfaces are planar ground engaging surface.

The mining apparatus according to any one of the preceding claims, wherein each track assembly includes a continuous track member, at least one drive wheel engaging the continuous track member to drive the track assembly and a plurality of idler wheels engaging the continuous track member for retaining the continuous track member in a desired shape.

The mining apparatus according to claim 7, wherein the track assembly is driven in a clockwise or anticlockwise direction by means of a first permanent- magnet synchronous motor.

The mining apparatus according to any one of the preceding claims, wherein the first and second ground engaging surfaces respectively extend between two wheels.

The mining apparatus according to any one of the preceding claims, wherein each continuous track assembly includes a pair of first ground engaging surfaces running surfaces located adjacent each other and a pair of second ground engaging surfaces located adjacent each other, with the respective pairs opposing each other.

1 1 . The mining apparatus according to any one of the preceding claims, wherein each of the track assemblies is shaped in the form of a parallelogram, in plan view.

The mining apparatus according to any one of the preceding claims, wherein the plurality of continuous track assemblies are steerable in that they are pivotally movable relative to the vehicle chassis about an operatively vertical axis.

The mining apparatus according to any one of the preceding claims, including a tool supporting arrangement positioned on the vehicle chassis and a first tool supported on the tool supporting arrangement for carrying out work on a rock face.

The mining apparatus according to claim 13, including a second tool supported on the tool supporting arrangement for carrying out work on the rock face.

15. The mining apparatus according to claim 14, wherein the first tool is a drill and the second tool is a mechanical rock breaker.

A mining apparatus comprising:

a vehicle chassis supporting a first tool for carrying out work on a rock face; and

stabilizing means for abutting and stabilizing the apparatus against a support surface whilst the first tool is carrying out work on the rock face.

17. The mining apparatus according to claim 16, wherein the support surface is any one or more of a side wall, a hanging wall and a foot wall.

18. The mining apparatus according to claim 17, wherein the side wall is a rock face.

19. The mining apparatus according to claim 17, wherein the stabilizing means includes an abutting member for abutting against the side wall adjacent to where the first tool is to carry out work.

20. The mining apparatus according to claim 19, including a tool supporting arrangement positioned on the vehicle chassis, the tool supporting arrangement having a tool carriage for supporting the first tool, with the abutting member being located on an end of the tool carriage.

21 . The mining apparatus according to claim 19 or 20, wherein the abutting member a resilient body which prevents the first tool from slipping, in use.

22. The mining apparatus according to claim 17, wherein the stabilizing means includes a first stabilizing assembly having a first extendible member for abutting against the hanging wall.

23. The mining apparatus according to claim 22, wherein the first stabilizing assembly includes a second extendible member for abutting against the foot wall to thus anchor the apparatus between the hanging and foot walls.

24. The mining apparatus according to claim 23, wherein the first and second extendible members are a pair of cylinders which are telescopically extendible in opposing directions.

The mining apparatus according to claim 23 or 24, wherein the stabilizing means is able to lift the vehicle chassis from the foot wall so that it floats between the hanging and foot walls.

The mining apparatus according to any one of claims 22 to 25, including a second stabilizing assembly which is similar to the first stabilizing assembly, the first and second stabilizing assemblies being spaced along the length of the apparatus and respectively located towards front and rear ends of the apparatus.

A mining apparatus comprising a vehicle chassis supporting first and second tools for carrying out work on a rock face when they are respectively located in an operative position, the tools being laterally displaceable such to be interchangeable in the operative position.

The mining apparatus according to claim 27, wherein the tools are laterally displaceable by being mounted on a tool support and displaceable along a length of the tool support by means of at least one tool support actuator.

29. The mining apparatus according to claim 27 or 28, wherein the tools are axially displaceable which is, in use, in a direction towards and from the rock face.

30. The mining apparatus according to claim 29, wherein the tools are axially displaceable by the tool support being mounted on a tool carriage which is displaceable along a length of the tool carriage on carriage tracks by means of at least tool carriage actuator.

31 . The mining apparatus according to claim 30, wherein the tool support and tool carriage form part of a tool supporting arrangement which is positioned on the vehicle chassis, the tool supporting arrangement including a telescopically extendible arm which is secured at its first end on the vehicle chassis and supports the tool carriage and tool support at an opposing second end.

The mining apparatus according to any one of claims 27 to 31 , wherein the first tool is a drill and the second tool is a mechanical rock breaker. 33. The mining apparatus according to a method of working on a rock face including the steps of:

providing a mobile mining apparatus having a drill and a mechanical breaker for carrying out work on a rock face;

orientation the drill to a preferred orientation relative to the rock face;

- drilling a hole in the rock face with the drill;

moving the drill out of alignment with the hole;

moving the mechanical breaker in line with the hole; and

fracturing the hole with the mechanical breaker.

34. The method according to claim 33, wherein the apparatus remains in position whilst the drill is moved out of alignment and the mechanical breaker is moved in line with the hole. 35. The method according to claim 33 or 34, wherein the apparatus remains in position whilst orientating the drill to the preferred orientation.

The method according to any one of claims 33 to 35, including the step of stabilizing the apparatus against a support surface before and during the drill and mechanical breaker is carrying out work on the rock face.

37. The method according to claim 36, wherein the support surface is any one or more of a side wall, a hanging wall and a foot wall. 38. The method according to any one of claims 33 to 37, wherein the step of orientating the drill to a preferred orientation includes any one or more of the further steps:

pivotally moving the drill about an x-axis;

pivotally moving the drill about a y-axis;

- pivotally moving the drill about a z-axis;

laterally moving the drill along an x-axis;

laterally moving the drill along the y-axis,

laterally moving the drill along a z-axis;

the X-, y- and z-axes being orthogonal to each other.

39. A method of adjusting the orientation of a continuous track assembly relative to the ground, the method including the steps of:

providing a continuous track assembly having a ground engaging surface and a motor for pivotally displacing the ground engaging surface about a pivoting axis relative to the ground;

providing a reference input current to the motor for maintaining the ground engaging surface in a predetermined orientation relative to the ground; and adjusting the orientation of the ground engaging surface when the input current required to maintain the ground engaging surface in the predetermined orientation relative to the ground deviates from the reference input current.

40. The method according to claim 39, including the further step of pivotally displacing the ground engaging surface upwards when the input current is greater than the reference input current.

41 . The method according to claim 39 or 40, including the further step of pivotally displacing the ground engaging surface downwards when the input current is less than the reference input current.

42. The method according to any one of claims 39 to 41 , wherein the predetermined orientation is a neutral orientation, more particularly a horizontal orientation.

43. The method according to any one of claim 39 to 42, including the step of calculating the reference input current when the ground engaging surface is in the predetermined orientation relative to the ground. 44. The method according to any one of claims 39 to 43, wherein the ground engaging surface is a planar ground engaging surface.