AU694510B2 - Mine roof support - Google Patents

Description

S F Ref: 306194

AUSTRALIA

PATENTS ACT 1990 COMPLETE SPECIFICATION FOR A STANDARD PATENT

ORIGINAL

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S S S S i r Name and Address of Applicant: Actual Inventor(s): Address for Service: Invention Title: The ANI Corporation Limited Pacific Highway Sennetts Green New South Wales 2290

AUSTRALIA

Ken Musgrove Spruson Ferguson, Patent Attorneys Level 33 St Martins Tower, 31 Market Street Sydney, New South Wales, 2000, Australia Mine Roof Support ASSOCIATED PROVISIONAL APPLICATION DETAILS [311 Application No(s) [33] Country PM6546 AU [32] Application Date 29 June 1994 The following statement is a full description of this invention, including the best method of performing it known to me/us:- 5815 I MINE ROOF SUPPORT Field of the Invention The following invention relates to a support for a mine roof. More particularly, though not exclusively, the invention relates to a device to assist in supporting strata close to the mining face.

Prior Art The main form of roof control in underground mining comprises the use of rock bolts which are anchored to the rock and fitted with one of a number of devices for retaining the roof rock, Such devices are particularly necessary in areas where the rock lo is of a scaly or fragmented nature which is often caused by induced stress from load or pressure after mining.

To retain the roof rock it has been known to augment the normal steel plate washers used in conjunction with the rock bolt, a long plate referred to as a strap, or alternatively, areas of weldmesh. It has been found that the effectiveness of 15 weldmesh is negated due to sag and whip in the mesh when being applied to the roof area, thus causing the mesh to sag upon fixing. Consequently, the mesh is not load bearing throughout its full length. The problem with whip is also prevalent with the S• handling of the material both in the transportation and installation process.

Object of the Invention It is the object of the present invention to overcome or substantially ameliorate at least one of the above disadvantages.

Disclosure of the Invention S, There is disclosed herein a mine roof support having: a grid of crossing elongate members interconnected to one another to form a 25 substantially planar mesh adapted to be fastened against a mine roof, some of said elongate members including a deformed segment or segments, which themselves include portions which are angled from each other and reside out of the plane of the mesh to 0 0. improve rigidity of the mesh, wherein a substantial area of the grid of crossing elongate members does not S 30 include said deformed segment or segments.

For example, the mesh might comprise a plurality of first parallel elongate members extending in a first direction, and a plurality of second elongate members extending in a second direction substantially at right angles to said first direction.

Preferably, in such an arrangement, where one or more of the first elongate members reside in a plane out of the main plane of the mesh, the adjoining second elongate members are deformed at either side of the out-of-plane first elongate members.

Furthermore, one or more of the second elongate members might reside in a plane out of the main plane of the mesh, Such elongate members, in combination with the out 1 of plane first elongate members might define a secondary grid structure.

[N\LIILL]00217:KEIH LICII~ ~-arsll~-ma~aR loaarra~ Alternatively, remote elongate members on opposing lateral edges of the mesh might reside out of the main plane of the mesh as a result of revolute deformation of tilhe crossing elongate members, or bending of the crossing elongate members to both sides of the main plane of the mesh.

s As an advantage of the above disclosed invention, a simple, yet effective roof support is provided having sufficient stiffness throughout its length to ease handling and positioning against the mine during installation. Furthermore, it is considered that such increased stiffness would generally improve the efficiency with which a mine roof may be supported.

There is further disclosed herein a method of supporting a mine roof, the method including bolting the mine roof support of any one of the preceding claims to a mine roof such that at least part of the bolts pass through the mesh, and further wherein the roof support is secured to the bolts by appropriate nuts and washers.

Brief Description of the Drawings Preferred forms of the present invention will now be described by way of example Swith reference to the accompanying drawings wherein Figs. 1 to 4 are schematic S* perspective illustrations of various alternative embodiments of a root supporting mesh structure.

Description of the Preferred Embodiment In Fig. 1 there is schematically depicted a mesh structure 10 in an upside-down orientation. Structure 10 comprises a plurality of lengthwise wires 11 and a plurality of crosswise wires 12 each interconnected to the lengthwise wires 11 by appropriate welding. Each wire 11 is typically approximately 4.5 metres in length. Two of the lengthwise wires 13 are raised out of the main plane of the structure 10. To this end, the crosswise wires 12 are deformed at 14 by a cold forming process to form the shaped deformation. In use, the structure 10 would be inverted such that the main plane of the same may be placed flush against a mine roof for bolting thereto. Typically, four essentially collinear roof bolts at approximately 1 metre spacings would pass through the mesh between the shaped deformations. Typical anchoring locations are indicated 30 by the letter B in Fig. 1.

It would be advantageous to provide the longitudinal wires above the transverse wires in the in-use orientation of the structure 10, That is, the longitudinal wires should preferably reside adjacent the mine roof.

The term "wires" herein is intended to mean steel rod of sufficient thickness to maintain an essentially rigid structure of sufficient rigidity for the purpose at hand.

Fig. 2 shows an alternative structure 20 wherein laterally opposed edges of the structure are deformed to provide an up-turned and down-turned structure.

[N:\LIBLL]00217:KEH I I I-I In Fig. 3 there is schematically depicted a structure 30 similar to that depicted in Fig. 1, however with additional crosswise deformations 41 these deformations are similar to those extending lengthwise in this embodiment and that of Fig, 1, It should be appreciated that the embodiments of Figs. 1, 2 and 3 are readily stackable, one upon another with high stacking density.

Although Fig. 1 shows elongate elements 13 at or near the peak of the deformed cross-wise elements 12, no such elements need reside within the deformed portion of the mesh.

For example, and as shown in Fig, 3, the deformations 41 are located between the adjacent cross-wires.

Fig. 4 shown an alternative embodiment 40 wherein the desired beam elements 51 are provided by downwardly folding the peripheral edge portions of the mesh such that the transverse elongate members are each deformed to provide a revolute edge portion.

It should be appreciated that modifications and alterations obvious to those skilled in the art are not to be considered as beyond the scope of the present invention. For example, rather than providing the roof support as a mesh, a flat plate might similarly be Sdeformed into the desired configuration.

s [N:\LIBLL]00217:dss II M

Claims (8)

1. A mine roof support having: a grid of crossing elongate members interconnected to one another to form a substantially planar mesh adapted to be fastened against a mine roof, some of said elongate members including a deformed segment or segments, which themselves include portions which are angled from each other and reside out of the plane of the mesh to improve rigidity of the mesh, wherein a substantial area of the grid of crossing elongate members does not include said deformed segment or segments.

2. The mine roof support of claim 1 wherein the mesh comprises a plurality of first parallel elongate members extending in a first direction, and a plurality of second elongate members extending in a second direction substantially at right angles to said first direction.

3. The mine roof support of claim 2 wherein one or more of the first elongate members reside in a plane out of the main plane of the mesh, the adjoining second elongate members being deformed at either side of the out-of-plane first elongate members.

4. The mine roof support of claim 3 wherein one or more of the second elongate members resides in a plane out of the main plane of the mesh.

The mine roof support of claim 1 wherein remote elongate members on opposing lateral edges of the mesh reside out of the main plane of the mesh as a result of revolute deformation of the crossing elongate members, or bending of the crossing elongate members to both sides of the main plane of the mesh.

6. A method of supporting a mine roof, the method including bolting the mine roof support of any one of the preceding claims to a mine roof such that at least part of the bolts pass through the mesh, and further wherein the roof support is secured to the bolts by appropriate nuts and washers.

7. A mine roof support substantially as hereinbefore described with reference to the accompanying drawings.

8. A method of supporting a mine roof, the method being substantially as hereinbefore described with reference to the accompanying drawings. Dated 12 June, 1998 The ANI Corporation Limited Patent Attorneys for the Applicant/Nominated Person SPRUSON FERGUSON [N:\LIBLL100217:KEH I I Mine Roof Support Abstract A mine roof support (10) comprises a grid of crossing elongate members (11, 12) interconnected to one another to form a substantially planar mesh adapted to be fastened against a mine roof. The mine roof support has some of the elongate members (12) deformed at (14) out of the plane of the mesh to improve rigidity of the mesh. 0." [tJALBLL1OO21 7!dSS