GB2089411A - Improvements in or relating to mine roof supports - Google Patents

Abstract

A mine roof support for use at the face or gate end area of a mine working comprises a base member 22 a roof-engaging member 24 and three props, such as hydraulic jacks, to urge them apart. The base member 22 has a part 86 extending laterally from the part carrying the jack seatings 82. The part 86 has its uppermost surface adapted to carry a stage loader conveyor 84, which extends with its conveyance direction longitudinally of the support. The base member 22 and roof-engaging member 24 present an overall generally C-shape, the laterally-projecting part 86 of the base member comprising the lower part of the 'C'. <IMAGE>

Description

SPECIFICATION Improvements in or relating to mine roof supports The invention relates to mine roof support systems, especially for use in the gate-or-face end area of a mine-working of the longwall kind.

In such workings, mineral removed from the face is transported by a face conveyor to the gate or face end area at one end of the face, where it is transferred to another conveyor extending away from the face along a roadway, usually referred to as the "loader gate". The actual transfer often takes place by means of a stage loader conveyor which comprises a relatively short, armoured conveyor which receives the material from the face conveyor and deposits it onto a belt conveyor, which then carries it along the roadway to the main gate.

The gate or face end area, often formed by over-running the mining machine beyond the end of the row of face-roof supports, must be supported independently of the face area and roadway, at least until the ripping lip is removed as the roadway is advanced for establishment of the permanent roadway support system usually arches.

Support in this area must provide good accessibility for the machinery it accommodates, such as the face conveyor drive and stage loader conveyor, and also general access to the face.

Previously roof bars and separate props have been used to support the mine roof in the gate or face end, the bars and props being dismantled and erected as the ripping lip is removed and the loader gate progresses as is conventional for the well-known prop-and-bar system.

Though such an arrangement provides for good access and support for this area, the erection and dismantling being done by hand, is very time consuming and subject to human error.

Consequently the rate at which the face can be advanced is limited by the rate at which the gate end is advanced, a problem which is exacerbated by the development of automatically advancing face support systems, hence advantage from mechanising the roadway support system.

An object of the present invention is to eliminate, or at least mitigate, this problem.

According to the present invention a mine roof support for use at the face of gate end area of a longwall mine working, comprises a base member, a roof-engaging member hingedly connected thereto, and prop means to urge them apart, wherein the base member has a part supporting the prop means and a part extending laterally therefrom and serving to locate a conveyor with its conveyance direction extending longitudinally of and in a direction of advance for the support.

The arrangement is such that, in use, the conveyor extends in the direction of advance i.e.

generally away from the conveyance direction of the face conveyor from which it receives the mined material.

Preferably the base member, prop means and roof engaging member take a generally C-shaped form, the laterally-projecting part of the base member comprising the lower part of the 'C'.

The laterally-projecting part may be arranged such that the conveyor located thereupon slopes downwardly and away from the prop means, an advantage of this inclination being that the mined material received or deposited thereupon from the face conveyor will be distributed more evenly across the width of the stage loader conveyor.

In a preferred embodiment the roof-engaging member takes the form of a cantilever canopy coupled to the base member by at least one lemniscate linkage coupled to the side of the base furthest from the conveyor. A seating for the bottom end of the or each prop means is also positioned at that side of the base, whereas the upper end of the or each prop means is coupled to the roof engaging member at a position spaced from the linkage, i.e. nearer its free end. Such an arrangement provides space, and protection, for the conveyor beneath the overhanging canopy of the roof engaging member.

The roof-engaging member may have extension bars or portions extending longitudinally from that end of the roof-support adjacent the face.

Similarly extension portions may be provided on the base member. The space between the extensions then being capable of housing face conveyor drive machinery. Also the space will permit the end of the face conveyor to project above the stage loader conveyor to deposit the mined material thereupon.

Preferably several props, for example three, are spaced along the length of the support member in a row adjacent the conveyor supporting part, conveniently alternated with the aforesaid linkages.

The roof support may be provided with means for advancing it as the face advances. For example the support may be self advancing. In particular the roof engaging member and base member could each be in two parts, the leading parts being coupled to the trailing parts by double-acting advancing rams and having their own prop means to urge them apart. The leading parts might if preferred, be coupled to the face conveyor for advancement therewith so as to ensure that the end of the face conveyor maintains its position relative to the stage loader conveyor.

An embodiment of the invention will now be described by way of example only with reference to the accompanying drawings in which: Figure 1 is a side view of a mine-roof support in the face or gate end area of a mine working.

Figure 2 is an end view of the mine-roof support, as viewed from the roadway.

Figure 3 is an end view corresponding to Figure 2, of a modified mine-roof support.

In Figures 1 and 2, the mine-roof support 10 is shown in the gate or face end area 12 at the junction between the face 1 4 and roadway 1 6 of a longwall mine-working. Figure 1 is a section through the area viewed from a position along the face and Figure 2 a section viewed from the roadway.

The area 12 is formed, as a continuation of the face area, by allowing the face cutter to overrun the endmost roof support 18 of the row of similar such supports positioned along the face. The area 12 consequently is the same height as the face area and has a generally semi-cylindrical sidewall 20 extending away from the face towards the roadway 16.

The roof support 10 comprises elongate base and roof-engaging members 22 and 24, respectively. The roof-engaging member has two parts 26, 28 connected to each other by a hinged coupling 30, the pivotal axis of which extends across the width of the support 10.

The roof-engaging member is supported as a cantilever by four sets of lemniscate linkages 32, 34, 36 and 38 spaced apart along the length of the base member and to one side thereof, and three hydraulic jacks 40, 42 and 44, intercalated between the linkages. Each linkage comprises a pair of links 46, 48 extending side-by-side between a pair of arms 50, 52, projecting downwards and laterally from the roof-engaging part of the roof member, and a pair of upstanding lugs 54, 56 positioned adjacent one side of the base member. Corresponding ends 58 and 60 of the links 46, 48 respectively, are connected pivotally to the arms 50, 52 by means of pins 62 and 64 extending through corresponding holes 66 and 68 spaced apart along the length of the arms.

The opposite ends 70,72 of the links 46,48 are connected to the upstanding lugs 54, 56 of the base member by pins 74 and and 76 extending through spaced holes 78 and 80, respectively.

Each hydraulic jack 40, 42, or 44, extends between a seating 82 between adjacent sets of lugs on the base member and a seating 84 at such a position on the roof member that the hydraulic jack is inclined relative to the vertical. The arrangement of the linkages and hydraulic jacks is such that, as the jacks extend, the roof member will be raised generally vertically.

A part 86 of the base member 22, extending laterally from the part carrying the jack seatings 82 and lugs 54, 56, has its uppermost surface adapted to carry a stage loader conveyor 85, which extends along the length of the support. As shown in Figure 2, the conveyor 84 slopes downwardly across its width and is supported at its lowermost edge by a lip 87 projecting upwardly from the edge of the base member. This inclination helps to distribute the mined material evenly across the width of the stage loader conveyor. A spillage plate 88, conveniently secured to the sides of the lugs 54, 56 of the base member, extends along the stage loader conveyor and serves to keep the mineral on the conveyor.

The end 90 of the stage loader conveyor projecting into the roadway 16, extends upwards to deliver its contents onto the usual beltconveyor 92 for conveyance along the roadway.

The opposite end 93 of the stage loader conveyor, and its associated drive motor, are positioned beneath the end 94 of the face conveyor. As can best be seen from Figure 1, at that end of the roof support 10 which is nearest to the face, the roofengaging part 26 has a forwardly projecting extension 96 beneath which the face conveyor drive motor 98 and associated drive 100 can be accommodated.

In use, mined material carried by the face conveyor is deposited upon the end 93 of the stage loader conveyor 84, which transfers it, in the direction of arrow A, to the belt conveyor 92.

When, due to the face advancing, it becomes necessary to move the roof-support 10, the hydraulic jacks 40, 42 and 44 are lowered and the support moved bodily towards the face, conveniently by portable rams lodges against a suitable anchorage, for example an arch 102 supporting the roof of the roadway 16. The props are then raised again and the roadway advanced by removing the ripping lip 93.

The stage loader conveyor may be left in place and moved with the support. Alternatively the conveyor may serve as the anchorage relative to which the support is moved by the aforementioned rams, the base part 22 then sliding beneath the stage loader conveyor, which can then be slid along the base part 22, once the support is repositioned, to restore it to its original position with one end adjacent the face conveyor.

It is also envisaged that the stage loader conveyor might be attached to the face conveyor, or the endmost face-roof support, so as to be moved therewith as the face machinery is advanced.

A further alternative is for the roof support to be self-advancing. Thus, the roof-engaging member 24 and base member 22 could each have two parts, coupled together by an advancing ram, the leading and trailing parts of the members having respective separate prop means to urge them apart. To advance the support, the leading prop means would be lowered, the advancing rams extended to push the leading parts forwards, then the leading prop means raised again. The prop means of the trailing parts would then be lowered, the advancing rams contracted to draw the trailing parts towards the face, then the trailing prop means raised again.

An advantage of the generally C-shaped form of the support is that the cantilever roof-engaging member forms a canopy over the stage loader conveyor. Thus, in addition to supporting the roof, the member protects the conveyor from falling debris. Moreover, the arrangement provides much improved access to the conveyor and reduces the risk of the stage loader conveyor becoming jammed with material, as sometimes occurs where the conveyor extends through conventional roof supports.

A further advantage of the C-shaped form is that the support utilises better the restricted area of a gate-or-face-end area having a semicylindrical sidewall, as formed by overrunning the face cutter.

A modified support in which the C-shaped form is emphasized, is shown in Figure 3, parts corresponding to parts in Figures 1 and 2 being identified by the same reference numerals. Thus the modified support has a base member 22, stage conveyor 84, prop means 40-44, and lemniscate linkages 46, 48 all similar to those of the support of Figure 2. The roof-engaging member 120, however, has a generally arcuate faceted outer surface carried by a plurality of vertical rib members 122 each tapering in successive straight-sided stages from a broad vertical part 124 to a narrow, generally horizontal part 126.A pair of holes 128 and 130 are provided in the vertical part 124 for pivotal connection of the ends of the links, and a seating 1 32 is provided in the underside of the broadest portion of the part 1 26 to receive the uppermost end of the prop means.

It is envisaged that instead of merely being a separate unit of conventional construction located or supported by the roof-support, the stage loader conveyor might be an integral part of the roof support, which might then also carry suitable drive means for the stage loader conveyor.

It should be appreciated that embodiments of the invention are particularly useful for use where thin seams are being worked, where access to the gate or face end area for example, to set props and roof bars manually would be very restricted. An advantage of self-advancing embodiments is that they may be controlled automatically, along with an automatically-advanced face support system.

Claims (14)

1. A mine roof support for use at the face or gate end area of a longwall mine working, comprising a base member, a roof-engaging member hingedly connected thereto, and prop means to urge them apart, wherein the base member has a part supporting the prop means and a part extending laterally therefrom and serving to locate a conveyor with its conveyance direction extending longitudinally of and in a direction of advance for the support.

2. A mine roof support according to claim 1 located at the end of a mine face supported by a row of mine roof supports, wherein the conveyor has its said conveyance direction transversely of and away from the mine face and a face conveyor associated with the row of mine roof supports.

3. A mine roof support as claimed in claim 1 or claim 2, wherein the base member, prop means and roof-engaging member take a generally C-shaped form, the laterally-projecting part of the base member comprising the lower part of the 'C'.

4. A mine roof support as claimed in claim 1,2 or 3, wherein the laterally-projecting part is arranged such that the conveyor located thereupon slopes downwardly and away from the prop means.

5. A mine roof support as claimed in any preceding claim, wherein the roof-engaging member is a cantilever canopy coupled to the base member by at least one lemniscate linkage coupled to said side of the base furthest from the conveyor.

6. A mine roof support as claimed in any preceding claim, wherein a seating for the bottom end of the or each prop means is positioned at said side of the base, whereas the upper end of the or each prop means is coupled to the roofengaging member at a position spaced from the linkage and nearer its free end.

7. A mine roof support as claimed in claim 5 or claim 6, wherein the roof-engaging member has extension bars or part extending longitudinally from the leading end of the roof-support in the direction of its advance.

8. A mine roof support as claimed in any preceding claim, wherein the base member has extension portions.

9. A mine roof support as claimed in claim 8, wherein space between the extensions portions affords accommodation for face conveyor drive machinery.

10. A mine roof support as claimed in claim 8 with claim 2, wherein the end of the face conveyor projects above the stage loader conveyor to deposit the mined material thereupon.

11. A mine roof support as claimed in any preceding claim, wherein several props are spaced along its length in a row adjacent the conveyor supporting part.

12. A mine roof support as claimed in claim 11 with claim 4, wherein three props are spaced along its length in a row adjacent the conveyor supporting part and alternate with two or more said linkages.

13. A mine roof support as claimed in any preceding claim, wherein the roof-engaging member and base member are each in leading and trailing parts, the leading parts being coupled to the trailing parts by double-acting advancing rams and having their own prop means to urge them apart.

14. A mine roof support as claimed in any preceding claim further including means for advancing it as the face advances.

1 5. A mine roof support as claimed in claim 14 with claims 2 and 13, wherein the leading parts are coupled to the face conveyor for advancement therewith so as to ensure that the end of the face conveyor maintains its position relative to the stage loader conveyor.

1 6. A mine roof support substantially as herein described with reference to and as illustrated in the accompanying drawings.