GB1590422A - Mining equipment - Google Patents

Description

(54) MINING EQUIPMENT (71) We, LOCKWOOD BENNETT LIMI TED, a British Company of 5 Orgreave Road, Handsworth, Sheffield, do hereby declare the invention for which we pray that a patent may be granted to us and the method by which it is to be performed, to be particularly described in and by the following statement: This invention relates to shields adapted to be attached to the rear of self-advancing, hydraulically powered mine roof supports, and also to mine roof supports incorporating such shields. These shields may be anti-flushing shields or may form part of a debris stowing or packing apparatus.

Anti-flushing shields are employed at the goaf side of the supports, the latter being located along an advancing or retreating mineral face, to prevent debris from the caving roof behind the supports entering the travelling way of the supports.

Known forms consist of chains, and/or plates, usually suspended from roof beams of the supports. However, with anti-flushing shields which consist of or incorporate plates, the plates usually extend to a width greater than that of the supports so that problems are usually encountered when moving the supports, either in the course of normal advance as the adjacent mineral face is advanced, or upon removal of the supports from one location e.g. after a mineral seam has been worked out. Stowing or packing apparatus is used either to stdw or pack debris, stone etc. resulting from the driving of a roadway, into a pack hole to one or both sides of a mine roadway, to assist in supporting the roof adjacent the roadway, or for filling worked out mineral seams with unwanted debris.

Various proposals have been put forward to mechanise the stowing or packing operation, to replace the traditional slusher bucket system and/or to replace the building of packs manually, so that the rate of pack building can keep pace with the rate of advance of a mineral face e.g. coal. One such proposal presently in use in British coal mines comprises one or more chains adapted to extend over the length of the pack hole or seam required to be stowed with debris, the chain(s) being guided and supported at its ends end tensioned, so that a blade carried by the chain may sweep debris from the vicinity of a roadway into the pack hole or seam. A pack retaining shield is provided and comprises a plurality of contiguous elements each adapted to be mounted on a rear and of a self-advancing, hydraulically-actuated, mine roof support.

Such roof supports are also usually provided with rearward cantilever extensions, to keep the pack hole "open" by preventing premature caving of the roof before pack building operations have been completed. However, when roof conditions are particularly poor, even such cantilever extensions are inadequate to maintain the pack hole "open" until such time as the required amount of debris has been packed and hence mechanised packing systems have not proved advantageous where such poor roof conditions exist, and thus, the practice has been to erect permanent timber props between adjacent selfadvancing mine roof supports, the props remaining behind as the self-advancing roof supports are advanced and ensuring that the pack hole remains open while debris is packed by conventional and largely manual methods.

According to the present invention, a mine shield comprises a substantially planar shield element, arranged to be attached laterally with respect to the direction of advance of a self-advancing, hydraulically-powered, mine roof support, and to a rearward end thereof, the element being provided with at least one displaceable door at least partially located within a hollow shield element having open ends and selectively movable with respect to its hollow shield element between a laterally extended position and a laterally retracted position.

The invention also includes a self advancing, hydraulically-powered, mine roof sup port provided with a mine shield as defined above.

Thus, in use, the door or doors of the shield elements of adjacent supports are normally extended towards an adjacent shield element to form a continuous shield, and hence over the major part of a longwall mineral face the shield elements constitute solely anti-flushing shields and prevents ingress of debris between adjacent supports to obstruct the travelling way while over a minor part of the face e.g.

30 yds. the shield elements additionally constitute a pack retaining shield (for a pack being built out for 30 yds. from a roadway) and may advantageously form part of a mechanised packing arrangement.

With such a packing arrangement, if poor roof conditions are encountered, permanent timber props may be set between adjacent powered supports, such that when those supports are advanced, the respective doors may be previously laterally retracted into their respective shield elements so that timber props may pass through the shield to remain in the pack hole, the doors thereafter being laterally extended to reform the shield.

In detail, the displaceable doors whether to serve simply as a pack retaining shield or to serve additionally as part of a mechanised packing arrangement may be slidable between retracted and extended positions. Preferably, one door is provided per shield element and the door may have a dimension, in the lateral direction, corresponding to that (or to half) of an individual shield element. In the embodiment where the shield element is provided with two displaceable doors, one or both may be extended laterally from the adjacent, open end of the hollow shield element.

The extendable doors, of whatever construction, are preferably retained in an extended position by providing a plurality of spaced holes in the extendable door(s) and a corresponding hole in the shield element, so that a locking pin may be inserted in the most appropriate hole for the desired extension of the door(s).

Instead of the displaceable door(s) being slidable, they may be pivotable between extended and retracted positions, again with some means being provided to retain the door(s) in an extended position.

Conveniently, the shield elements are bolted to the rear support and may comprise horizontally extending wear plates adjacent the goaf or pack. To enable the shields to be adaptable to different seam heights, two or more shield elements may be mounted one above the other as indicated by the seam height. The individual extendable doors of the superimposed shield elements may be connectable together in an extended position.

The displaceable door(s) of whatever construction may be displaceable by power means e.g. a hydraulic ram, preferably a double acting ram.

Again, with whatever construction of displaceable door(s) the latter may be connectable, in extended position, to an adjacent shield element e.g. by a pin. In the embodiment of hollow shield element having a slidable door with a dimension in the lateral direction corresponding to that of its shield element, the door may be manually extended, and it is not envisaged that such extension will be of more than half the lateral length of the door, so that a substantial portion of the door always remains within its shield element, whereby goaf or pack loads may be readily absorbed by the door -- whether this is a cantilever extension from its shield element or a non cantilever extension by having a connection at its otherwise free end, to an adjacent shield element.

The invention will now be described in greater detail, by way of example, with reference to the accompanying drawings, in which: Figure 1 is a view on the rear of a plurality of hydraulically powered, self-advancing, mine roof supports located side by side along a mineral face, these supports being provided with a mine shield in accordance with the invention; Figure 2 corresponds to Figure 1 but shows the mine shield in a different operative position; Figure 3 is a plan view of the supports of Figure 1; and Figure 4 is an enlarged detail of a door secured in an extended position.

In the drawings, each hydraulically powered, self-advancing mine roof support 1 comprises a pair of base members 2 seating on a mine floor 3 and a roof beam 4 arranged to make contact with the mine roof 5, upon extension of a plurality of hydraulically extensible chock legs (not shown) extending between the base members 2 and the roof beam 4. As best seen in Figure 3, each support 1 is provided with a forward cantilever extension 6 arranged to perform a roof supporting function above a scraper chain conveyor indicated at 7 and extending along a mineral face 8, a mining machine (not shown) being reciprocable along the conveyor 7 to remove mineral from the face 8. Also shown in Figure 3 are rearward cantilever extensions 9 likewise intended to control collapse of the mine roof 5 behind supports 1 as the latter advance, and to give some protection for a known packing apparatus mounted on and carried by the supports 1, the apparatus being described in greater detail in U.K.

Patent Specification 1,279,711. The packing apparatus is employed to sweep stone, debris etc. to build a pack 10 e.g. 30 yards long, adjacent a mine roadway to perform a roof supporting function adjacent the roadway, as well as to dispose of the stone etc. resulting from driving of the roadway.

Each support 1 carries at its rearward end, remote from the conveyor 7, a mine shield 11 comprising a hollow, planar shield element 12 having a central deck 13 separating an upper compartment 14 from a lower compartment 15, each compartment housing two displaceable doors 16 movable with respect to the shield element 12, the displaceable doors of each compartment 14, 15 being extendable in opposite lateral directions (with respect to the direction of advance, in use of each roof support 1) until they abut, or substantially abut, as shown in Figures 1 and 3, to complete the formation of an anti-flushing shield along the rear of the supports 1. As indicated in Figure 4, each door 16 is provided with a plurality of spaced holes 17 into one of which a pin 18, passing through a hole 19 in the shield element 12, may be located.As indicated in Figure 1, the superimposed doors 16 of each support 1 may be secured together in their extended position by a locking pin 20 passing through aligned holes in each door.

As indicated in Figures 2 and 3, in poor roof conditions, it may well be desirable to erect permanent timber props 21 between adjacent supports 1. It will be appreciated that despite the presence of an effective anti-flushing shield behind the supports 1, the timber props 21 may be readily set and retained in position during advance of the supports 1 as the latter advance in accordance with the advance of the mineral face 8, by sliding the doors 16 back into their respective compartments 14, 15 of shield elements 12, as indicated in Figure 2, and extending the doors after such passage, as indicated in Figure 3.

WHAT WE CLAIM IS: - 1. A mine shield comprising a substantially planar shield element, arranged to be attached laterally with respect to the direction of advance of a self-advancing, hydraulically-powered, mine roof support, and to a rearward end thereof, the element being provided with at least one displaceable door at least partially located within a hollow shield element having open ends and selectively movable with respect to its hollow shield element between a latrally extended position and a laterally retracted position.

2 A mine shield as claimed in Claim 1, wherein the or each displaceable door is slidably between retracted and extended positions.

3. A mine shield as claimed in Claim 1 or Claim 2, wherein one door is provided per shield element.

4. A mine shield as claimed in any preceding Claim, wherein the or each door has a dimension in the lateral direction corresponding to that of an individual shield element.

5. A mine shield as claimed in any one of Claims 1 to 3, wherein the or each door has a dimension in the lateral direction approximating to half the corresponding dimension of an individual shield element.

6. A mine shield as claimed in any preceding Claim, wherein the or each door is located externally of its shield element on the side thereof which in use is remote from the goaf or pack.

7. A mine shield as claimed in any preceding Claim, wherein the shield element is provided with two displaceable doors and one or both are extendable laterally from opposite ends of the shield.

8. A mine shield as claimed in any preceding Claim, wherein the or each door is positively retainable in anextended position.

9. A mine shield as claimed in Claim 8, wherein retention is effected by locking pin.

10. A mine shield as claimed in Claim 9, wherein a plurality of spaced holes are provided on the or each extendable door into a selected one of which holes the locking pin is insertable.

11. A mine shield as claimed in Claim 1 wherein the or each door is pivotable between extended and retracted positions.

12. A mine shield as claimed in Claim 11, wherein the or each door is positively retained in an extended position.

13. A mine shield as claimed in any preceding Claim, comprising a horizontally extending wear plate arranged to be located, in use, adjacent the goaf or pack.

14. A mine shield as claimed in any preceding Claim, wherein two or more shield elements are mounted one above the other.

15. A mine shield as claimed in Claim 14, wherein the individual extendable doors of the superimposed shield elements are connectable together when in an extended position.

16. A mine shield as claimed in any preceding Claim, wherein the or each displaceable door is manually moveable.

17. A mine shield as claimed in any one of Claims 1 to 15, wherein the or each displaceable door is movable by powered means.

18. A mine shield as claimed in Claim 17, wherein the powered means is a hydraulic ram.

19. A mine shield as claimed in Claim 18, wherein the ram is double-acting.

**WARNING** end of DESC field may overlap start of CLMS **.

Claims (23)

**WARNING** start of CLMS field may overlap end of DESC **. being described in greater detail in U.K. Patent Specification 1,279,711. The packing apparatus is employed to sweep stone, debris etc. to build a pack 10 e.g. 30 yards long, adjacent a mine roadway to perform a roof supporting function adjacent the roadway, as well as to dispose of the stone etc. resulting from driving of the roadway. Each support 1 carries at its rearward end, remote from the conveyor 7, a mine shield 11 comprising a hollow, planar shield element 12 having a central deck 13 separating an upper compartment 14 from a lower compartment 15, each compartment housing two displaceable doors 16 movable with respect to the shield element 12, the displaceable doors of each compartment 14, 15 being extendable in opposite lateral directions (with respect to the direction of advance, in use of each roof support 1) until they abut, or substantially abut, as shown in Figures 1 and 3, to complete the formation of an anti-flushing shield along the rear of the supports 1. As indicated in Figure 4, each door 16 is provided with a plurality of spaced holes 17 into one of which a pin 18, passing through a hole 19 in the shield element 12, may be located.As indicated in Figure 1, the superimposed doors 16 of each support 1 may be secured together in their extended position by a locking pin 20 passing through aligned holes in each door. As indicated in Figures 2 and 3, in poor roof conditions, it may well be desirable to erect permanent timber props 21 between adjacent supports 1. It will be appreciated that despite the presence of an effective anti-flushing shield behind the supports 1, the timber props 21 may be readily set and retained in position during advance of the supports 1 as the latter advance in accordance with the advance of the mineral face 8, by sliding the doors 16 back into their respective compartments 14, 15 of shield elements 12, as indicated in Figure 2, and extending the doors after such passage, as indicated in Figure 3. WHAT WE CLAIM IS: -

1. A mine shield comprising a substantially planar shield element, arranged to be attached laterally with respect to the direction of advance of a self-advancing, hydraulically-powered, mine roof support, and to a rearward end thereof, the element being provided with at least one displaceable door at least partially located within a hollow shield element having open ends and selectively movable with respect to its hollow shield element between a latrally extended position and a laterally retracted position.

2 A mine shield as claimed in Claim 1, wherein the or each displaceable door is slidably between retracted and extended positions.

3. A mine shield as claimed in Claim 1 or Claim 2, wherein one door is provided per shield element.

4. A mine shield as claimed in any preceding Claim, wherein the or each door has a dimension in the lateral direction corresponding to that of an individual shield element.

5. A mine shield as claimed in any one of Claims 1 to 3, wherein the or each door has a dimension in the lateral direction approximating to half the corresponding dimension of an individual shield element.

6. A mine shield as claimed in any preceding Claim, wherein the or each door is located externally of its shield element on the side thereof which in use is remote from the goaf or pack.

7. A mine shield as claimed in any preceding Claim, wherein the shield element is provided with two displaceable doors and one or both are extendable laterally from opposite ends of the shield.

8. A mine shield as claimed in any preceding Claim, wherein the or each door is positively retainable in anextended position.

9. A mine shield as claimed in Claim 8, wherein retention is effected by locking pin.

10. A mine shield as claimed in Claim 9, wherein a plurality of spaced holes are provided on the or each extendable door into a selected one of which holes the locking pin is insertable.

11. A mine shield as claimed in Claim 1 wherein the or each door is pivotable between extended and retracted positions.

12. A mine shield as claimed in Claim 11, wherein the or each door is positively retained in an extended position.

13. A mine shield as claimed in any preceding Claim, comprising a horizontally extending wear plate arranged to be located, in use, adjacent the goaf or pack.

14. A mine shield as claimed in any preceding Claim, wherein two or more shield elements are mounted one above the other.

15. A mine shield as claimed in Claim 14, wherein the individual extendable doors of the superimposed shield elements are connectable together when in an extended position.

16. A mine shield as claimed in any preceding Claim, wherein the or each displaceable door is manually moveable.

17. A mine shield as claimed in any one of Claims 1 to 15, wherein the or each displaceable door is movable by powered means.

18. A mine shield as claimed in Claim 17, wherein the powered means is a hydraulic ram.

19. A mine shield as claimed in Claim 18, wherein the ram is double-acting.

20. A mine shield as claimed in any

preceding Claim, wherein the or each displaceable door is connectable, when in its extended Dosition. to an adjacent shield element.

21. A mine shield as claimed in Claim 20, wherein the connection is by a pin.

22. A mine shield substantially as here- inbefore described with reference to the accompanying drawings.

23. A self-advancing, hydraulicallypowered mine roof support provided with a mine shield as claimed in any preceding Claim.