TECHNICAL FIELD

[0001] The present invention relates to safety in mines, constructions sites, and the like. In particular, although not exclusively, the invention relates to protecting persons and equipment from falling debris from the roof or rib of an underground mine.

BACKGROUND ART

[0002] The falling of debris, such as pieces of coal or rock, has long been a hazard in underground coal mines. In particular, pieces of coal that fall from a rib (wall) or roof have been known to injure and kill persons in the mine, even when relatively small.

[0003] In order to reduce the risk of injury from falling debris, roof and rib supports may be installed. The supports may, for example, utilise anchor bolts in the ribs, to anchor unstable rock or coal to stable rock or coal, and utilise support mesh or panels to directly support the roof or rib.

[0004] A problem with roof and rib support systems of the prior art is that they are manual labour intensive, and thus very expensive. Furthermore, roof and rib support systems of the prior art are prone to failure over time. This is particularly the case due to weathering, from

mechanical damage, and when there are changes in stresses in the support surfaces.

[0005] When defects are identified in the support systems of the prior art, a large barrier is generally installed until a support unit can repair the support. This may result in an area of the mine being closed off. This may be very costly for a mine, particularly if it restricts access to critical areas of a mine.

[0006] Furthermore, defects in a mine are typically scattered across the mine. As such, it is generally costly and time consuming to repair these portions of the system, as the support unit must move back and forth across the mine chasing the defects.

[0007] Similar problems exist outside of mining, including in the construction industry.

[0008] As such, there is clearly a need for an improved rib, wall, slope and roof safety system, and in particular a rib and roof safety system that is cost effective to install and maintain.

[0009] It will be clearly understood that, if a prior art publication is referred to herein, this reference does not constitute an admission that the publication forms part of the common general knowledge in the art in Australia or in any other country.

SUMMARY OF INVENTION

[0010] The present invention is directed to safety systems, which may at least partially overcome at least one of the abovementioned disadvantages or provide the consumer with a useful or commercial choice.

[0011] With the foregoing in view, the present invention in one form, resides broadly in a deflection system, for deflecting debris falling from a wall, slope or roof, the deflection system comprising:

two or more anchors;

a support line extending between the anchors; and

a deflection net, supported by the support line and spaced from the wall or roof, and configured to deflect debris falling from the wall or roof.

[0012] Advantageously, the system is configured to deflect debris, rather than holding it in place.

[0013] Preferably, the system includes an upper support line, for supporting an upper portion of the net, and a lower support line, for supporting a lower portion of the net.

[0014] The support line(s) may be housed in sock(s), which are attached to (e.g. sewn onto) edges of the net. The socks may be configured to protect the support lines and/or distribute force applied against the support lines to the net.

[0015] Alternatively, the support line(s) may be threaded through apertures of deflection net.

[0016] The net may be at least partly folded. The net may be folded along an upper edge. Both sides of the fold may be supported by the support line.

[0017] The support line(s) may been incorporated into the net at a time of manufacture. [0018] The line may comprise a steel line, or synthetic rope.

[0019] High visibility tape and/or protective sheathing may be placed around the line.

[0020] The system may include a third support line, for supporting a central portion of the net. The third support line may be used in certain areas, to reduce deflection, and not in other areas. This is particularly advantageous in tight spaces, where only low levels of deflection are appropriate.

[0021] The anchors may comprise steel plates, and an eye, to which the line is coupled. The steel plates may be about 200mm x 200mm in size and may be bolted to the roof or floor.

Mechanical apparatus may also be used as anchors.

[0022] The net may comprise a plurality of apertures. Each aperture may be about 55mm x 55mm in size.

[0023] The net may be formed of a polyester (PET) or polyvinyl alcohol (PVA), or a combination of mixture thereof, and may include Kevlar. The net may be woven.

[0024] Alternatively, the net may be formed of synthetic Kevlar.

[0025] The net may be coated with a flame -resistant coating. The net may be coated with an anti- static coating.

[0026] The net may be substantially rectangular, and include an anchor near each corner.

[0027] The deflection system may be configured to deflect debris from a wall. The wall may comprise a rib of a coal mine or a low and high wall in a metalliferous mine.

[0028] The net may extend along the length of the wall, and from an upper portion of the wall, to a lower portion of the wall.

[0029] The net may be configured to deflect the debris back towards the wall. The net may be configured to allow the debris to fall to the ground at a base of the net.

[0030] The anchors may be positioned on the wall from which debris is deflected.

Alternatively or additionally, the anchors may be positioned on a roof and/or floor adjacent to wall.

[0031] The deflection system may be configured to deflect debris from a roof.

[0032] The net may be angled towards a wall. This may provide that debris is deflected at an angle (rather than directly back) should debris fall directly downwards onto the net.

[0033] The net may include a resealable opening for removing debris caught by the net. The opening may be provided using a zip, or by remote control release.

[0034] The net is preferably elongate. The net may be about 40m x 1.7 to 2.7m. The net is, however, easily configurable to any size walls, including lengths, the ordination of the system can be modified according to the walls, side or roof being protected.

[0035] The deflection system may be configured to operate in any underground or surface mine. Suitably, the underground mine may comprise a coal mine and the debris may comprise coal.

[0036] Alternatively, the system may be configured to operate in a construction or civil site. The debris may, for example, comprise rock or building material.

[0037] The deflection net may be configured to deflect debris falling from the slope back towards the slope. In such case, the debris (e.g. a rock) slides down the face of the slope, rather than rolling and bouncing down, which in turn decreases speed of the debris through friction with the slope.

[0038] In such case, the net may be anchored at the top and bottom of the slope. A plurality of overlapping nets may be provided and anchored to the slope to cover a large area.

[0039] A support line may be coupled to a lower end of the mesh in a manner that allows space for material to be removed from a bottom end of the net.

[0040] In another form, resides broadly in a containment system, for containing debris falling from a wall, the containment system comprising:

two or more anchors;

a support line extending between the anchors; and

a containment net, supported by the support line adjacent to the wall and configured to contain debris falling from the wall.

[0041] Advantageously, persons are able to work near the wall without risking debris falling onto or trapping a person.

[0042] The wall may comprise a wall of a trench. A frame may extend into the trench, to provide support for the two or more anchors. The frame may be coupled to one or more concrete blocks located on an outside of the trench, to support the frame. The frame may be configured to engage with walls of the trench. One or more hydraulic rams may be used to bias the frame against the walls of the trench.

[0043] The frame may be used to avoid possible interaction infrastructure in the ground of the trench, which would otherwise occur if the frame was driven into the ground. [0044] In alternative embodiments, one or more anchors may be driven into a base of the trench.

[0045] The containment system may have a similar or identical structure to the deflection system described above.

[0046] Any of the features described herein can be combined in any combination with any one or more of the other features described herein within the scope of the invention.

[0047] The reference to any prior art in this specification is not, and should not be taken as an acknowledgement or any form of suggestion that the prior art forms part of the common general knowledge.

BRIEF DESCRIPTION OF DRAWINGS

[0048] Various embodiments of the invention will be described with reference to the following drawings, in which:

[0049] Figure 1 illustrates a perspective cutaway view of a rib deflection system, for deflecting debris falling from a rib (wall) of an underground mine, according to an embodiment of the present invention;

[0050] Figure 2 illustrates a front view of the rib deflection system of Figure 1, according to an embodiment of the present invention;

[0051] Figure 3a illustrates an end view of the rib deflection system of Figure 1, according to an embodiment of the present invention;

[0052] Figure 3b illustrates an end view of the rib deflection system of Figure 1, illustrating debris falling from a wall;

[0053] Figure 3c illustrates an end view of the rib deflection system of Figure 1, illustrating debris being deflected from the net;

[0054] Figure 3d illustrates an end view of the rib deflection system of Figure 1, illustrating debris on the floor and supported by the net;

[0055] Figure 4 illustrates an end view of a rib deflection system, according to an alternative embodiment of the present invention; [0056] Figure 5 illustrates a front view of the rib deflection system of Figure 4, according to an embodiment of the present invention;

[0057] Figure 6 illustrates a cross- sectional view of a rib deflection system, according to yet an alternative embodiment of the present invention;

[0058] Figure 7 illustrates an end view of a roof deflection system, according to an embodiment of the present invention; and

[0059] Figure 8 illustrates a bottom view of the roof deflection system of Figure 7, according to an embodiment of the present invention.

[0060] Preferred features, embodiments and variations of the invention may be discerned from the following Detailed Description which provides sufficient information for those skilled in the art to perform the invention. The Detailed Description is not to be regarded as limiting the scope of the preceding Summary of the Invention in any way.

DESCRIPTION OF EMBODIMENTS

[0061] Figure 1 illustrates a perspective cutaway view of a rib deflection system 100, for deflecting debris falling from a rib (wall) of an underground mine, according to an embodiment of the present invention. The rib deflection system 100 may prevent injury to worker and damage to machines, by deflecting falling debris away from the workers or machine.

[0062] The rib deflection system 100 comprises a deflection net 105, spaced away from a wall 110 of the mine, and supported by support lines 115, each of which extends between anchors 120. When debris falls from the wall 110a, it hits the deflection net 105, which deflects the debris back towards the wall 110a, where it may fall to a floor 110b of the mine. As such, machinery, such as a conveyor 125, and workers, are protected.

[0063] The net 105 extends along the length of the wall 110a, and from an upper portion, adjacent to a roof 110c of the mine, to a lower portion adjacent to the floor 110b. As such, debris falling from a large portion of the wall 110a is able to be deflected by the system 100.

[0064] As the net 105 is positioned between the wall 110a and the conveyor 125, any debris falling from the wall is prevented from damaging the conveyor, and is instead directed towards the floor of the mine adjacent to the conveyor 125.

[0065] As best illustrated in Figure 2, the support lines 115 are housed in socks 205, which extend across upper and lower edges of the deflection net 105. The socks 205 are sewn onto edges of the net 105, and provide protection to the support lines 115, and help distribute the force applied against the support lines 115 to a larger area of the deflection net 105.

[0066] The anchors 120 comprise steel plates 120a, which may be about 200mm x 200mm in size, which are bolted to the wall by M24 bolts, and an eye 120b, to which the line is coupled.

[0067] As best illustrated in Figure 3a, the deflection net 105 is spaced from the wall 110a. As such, the deflection net 105 is not configured to support or hold the wall 110a in place, but instead deflect debris falling from the wall 110a, as exemplarily illustrated in Figures 3b-3d.

[0068] Figure 3b illustrates a piece of rock 305 (e.g. coal) falling from the wall 110. The rock 305 falls downwards and outwards from the wall and hits the net 105, which flexes slightly, and causes the rock 305 to deflect back towards the wall 110, as illustrated in Figure 3c. The rock may deflect into the net multiple times (e.g. depending on the size of the rock and/or the size of the gap between the wall 110 and the net 105)

[0069] Figures 3a-3b illustrate the net 105 being substantially vertical. However, the skilled addressee will readily appreciate that the net may be angled to form a tapered space between the wall 110 and the net 105. For example, the net may extend inwards towards a bottom of the net, to provide a limited area in which debris falls. Alternatively, the net may extend outwards towards a bottom of the net if desired.

[0070] The line 115 typically comprises high strength steel or synthetic rope, which enables the line 115 to be tensioned. High visibility tape and/or protective sheathing may be placed around the rope to avoid damage to the rope by sharp objects.

[0071] The net 105 is typically formed of a polyester (PET) or polyvinyl alcohol (PVA) material, which is woven. Alternatively, the net 105 may be formed of synthetic Kevlar, or any other suitable material. The net 105 may be coated with a flame -resistant and/or anti-static coating, according to need.

[0072] The net 105 may comprise apertures that are about 55mm x 55mm in size. The net may be about 300g/m ² . The net may have an Ultimate Tensile Strength of greater than about 30kN/m2.

[0073] The net 105 may be provided in lengths of about 40m. Multiple lengths of netting may be provided to protect a longer area. In some embodiments, the net is about 1.7m high, but can vary in height, depending on the conditions and sizing of the area to protect

[0074] According to alternative embodiments, the anchors are placed on a roof and floor of the mine.

[0075] Figure 4 illustrates an end view of a rib deflection system 400, and Figure 5 illustrates a front view of an end portion of the deflection system 400, according to an embodiment of the present invention. The deflection system 400 is, much like the deflection system 100, for deflecting debris falling from a rib (wall) of an underground mine.

[0076] The system 400 comprises the deflection net 105, spaced away from the wall 110a of the mine, and deflects the debris back towards the wall 110a, where it may fall to the ground to protect workers and machinery, much like the system 100 of Figure 1. However, support lines 415 of the system 400, which extend along the net 105, extend between anchors 420 at the roof 110c and the floor 110b of the mine respectively.

[0077] In particular, and as best illustrated in Figure 5, the support lines 415 extend through the sock 205, and then either upwardly to anchors 420 in the roof 110c (in the case of the upper support line 415), or downwardly to anchors 420 in the floor 110b (in the case of the lower support line 415). This enables the wall 110a to be shielded without requiring any anchoring in the wall 110a. As a result, this enables flexible configuration of the net 105 with reference to the wall 110a, which may be particularly advantageous when placed against machinery, such as a conveyor 405, or in tight spaces.

[0078] In other embodiments, the net 105 does not include a sock for receiving the support lines 415, but instead the support lines 415 are threaded through the net 105. Also, the net 105 may be folded at least partly, to provide extra strength and reduce the likelihood of debris damaging the net 105.

[0079] The system 400 can also be partly or wholly supported with steel props to eliminate or reduce the need for floor pins.

[0080] Furthermore, in some embodiments, a third (or more) support line may be used to reduce deflection. This is particularly advantageous in tight spaces, where only low levels of deflection are appropriate.

[0081] Figure 6 illustrates a cross section of a portion of a rib deflection system 600, according to an embodiment of the present invention. The deflection system 600 is, much like the deflection systems 100 and 400, and is for deflecting debris falling from a rib (wall) of an underground mine.

[0082] The system 600 comprises a deflection net 605, spaced away from the wall 110a of the mine, and deflects the debris back towards the wall 110a, where it may fall to the ground, to protect workers and machinery, much like the system 100 of Figure 1 and the system 400 of Figure 4. However, the net 605 is folded, and support lines 615a-c are woven through the net at an upper end, and intermediate portion, and a lower end.

[0083] In particular, the net material is folded such an upper half of the net 605 comprises two layers of net material, and a lower portion of the net 605 comprises a single layer of net material. The upper support line 615a is threaded through both layers of net material, as is the intermediate support line 615b. The lower support line 615c is threaded through a single layer of net material.

[0084] The support lines 615a-c may be anchored at either end of the system 600 using any suitable means, such as the means described with reference to Figure 1, or the means described with reference to Figure 4.

[0085] The Inventor has discovered that by folding the net and threading the lines through the nets, as described above, the system is more resilient to tearing than if a sock is sewn onto the net as described in Figure 1 or Figure 4.

[0086] The intermediate rope may be installed to reduce deflection distance in certain areas only, such as next to critical equipment. As such, installation complexity may be reduced where low deflection is not essential, which reduces overall installation costs.

[0087] The above described rib deflection systems 100, 400, 600 may be adapted to deflect debris which may fall from the roof 110c of the mine. As such, a mine may be protected from the sides and from above.

[0088] Figure 7 illustrates an end view of a roof deflection system 700, according to an embodiment of the present invention. The deflection system 700 is much like the deflection systems 100, 400 and 600, but is for deflecting debris falling from a roof of an underground mine.

[0089] The system 700 comprises a deflection net 705, spaced away from the roof 110c of the mine, and deflects the debris falling from the roof 110c, where it may come to rest in a portion of the net 705where it is able to be safely removed, to protect workers and machinery.

[0090] Support lines 710 extend along a length of the net 705, in socks 205, and then outwardly to anchors 720 on opposite walls 110a of the mine. The net 705 is spaced from the roof 110c, and is angled towards one wall 110a of the mine. This provides that debris is deflected at an angle (rather than directly back) should debris fall directly downwards, as illustrated by exemplary debris 715 in Figure 7.

[0091] As best illustrated in Figure 8, a zip 725, which provides a resealable opening, extends along a length of the system 700, and can be opened to release debris from the net 705. A rope or other extension may be coupled to the zip to enable a worker to open the zip 725, and thus allow debris to fall to the ground, from a safe distance.

[0092] The systems described above may be used to provide a barrier when a defect is identified in a primary support mesh, for example, without having to immediately repair the primary support mesh. In particular, the systems may be used until secondary support crews are able to install a more permanent barrier, which in turn enables support crews to work more efficiently rather than jumping around over the mine depending on where the latest defect is (which is very inefficient and costly).

[0093] In some embodiments, the systems may be used to provide barriers on a more long term basis.

[0094] While the above describes installation onto anchors, the systems may be installed using existing bolts and anchors.

[0095] Furthermore, while the above systems have been primarily described with reference to coal mines, the systems may be used as barriers in other mining, underground or otherwise.

[0096] Similarly, the systems may be used in relation to construction trenches, as barriers against damaged structures, or the like.

[0097] In some embodiments, the system may comprise a containment system, for containing debris falling from a wall, such as a wall of a trench. In such case, the structure of the system may be similar, but with the net closer to the wall, to enable persons to work near the wall without risking debris falling onto or trapping the person.

[0098] In some embodiments, a frame may extend into the trench, to provide support for the anchors. This may simplify installation of the frame, and thus reduce costs. [0099] The frame may be coupled to one or more concrete blocks located on an outside of the trench, to support the frame. As such, the frame may be quickly and easily lifted into place.

[00100] The frame may be configured to engage with walls of the trench. As an illustrative example, one or more hydraulic rams may be used to bias the frame against the walls of the trench. The skilled addressee will readily appreciate, however, that the hydraulic rams may be replaced by any suitable biasing means.

[00101] Advantageously, the frame may be used to avoid possible interaction infrastructure in the ground of the trench, which would otherwise occur if the frame was driven into the ground.

[00102] In alternative embodiments, one or more anchors may be driven into a base of the trench, to either support a frame, as outlined above, or to support the net directly (or indirectly).

[00103] The containment system may have a similar or identical structure to the deflection system described above.

[00104] The systems described above are advantageously less expensive than corresponding secondary support structures, and are reusable. In particular, nets may be moved around a mine and used as required.

[00105] In the present specification and claims (if any), the word 'comprising' and its derivatives including 'comprises' and 'comprise' include each of the stated integers but does not exclude the inclusion of one or more further integers.

[00106] Reference throughout this specification to 'one embodiment' or 'an embodiment' means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment of the present invention. Thus, the appearance of the phrases 'in one embodiment' or 'in an embodiment' in various places throughout this specification are not necessarily all referring to the same embodiment.

Furthermore, the particular features, structures, or characteristics may be combined in any suitable manner in one or more combinations.

[00107] In compliance with the statute, the invention has been described in language more or less specific to structural or methodical features. It is to be understood that the invention is not limited to specific features shown or described since the means herein described comprises preferred forms of putting the invention into effect. The invention is, therefore, claimed in any of its forms or modifications within the proper scope of the appended claims (if any) appropriately interpreted by those skilled in the art.