Longwall mining roof supports

Abstract

A longwall mining system includes at least one face end roof support having a longitudinal length, and at least one near end roof support adjacent the face end roof support. The near end roof support has a longitudinal length substantially shorter than the face end roof support longitudinal length. There is also at least one face roof support adjacent the near end roof support, and the face roof support has a longitudinal length substantially shorter than the near end roof support longitudinal length. There is also a forward conveyor extending forward to and attached to the face end roof support, the at least one near end roof support, and the at least one face roof support, and a rearward conveyor extending rearward of and attached to the face end roof support, the at least one near end roof support, and the at least one face roof support. This creates an effective cave line at an angle to the coal face, that helps reduce the goaf pressure on the face end, thereby increasing the stability of the main gate roof support.

Claims

1. A main gate roof support comprising: a pair of elongated base members laterally spaced apart from one another, each base member including a first portion, a second portion, a first support pivotally coupled to the first portion, and a second support pivotally coupled to the second portion; a first shield pivotally coupled to the first portion of each base member; a first beam for engaging a roof, the first beam coupled to the first portions of the base members by the first supports, the first beam pivotally coupled to the shield; a second beam for engaging the roof, the second beam coupled to the second portions of the base members by the second supports; a bridge member pivotally coupled between each of the base members to permit movement of the base members relative to one another; and a sloughing plate pivotally coupled to one of the base members, the sloughing plate extending at least partially between the one base member and at least one of the first beam and the second beam.

2. The main gate roof support of claim 1, wherein the base members further include a third portion positioned between the first portion and the second portion, and further comprising a third beam for engaging the roof, the third beam pivotally coupled to the first beam and pivotally coupled to the second beam.

3. The main gate roof support of claim 2, wherein each base member includes a third support pivotally coupled to the third portion, and wherein the third beam is coupled to the third portions of the base members by the third supports.

4. The main gate roof support of claim 1, wherein the bridge member is a first bridge member pivotally coupled between the first portions of the base members, and further comprising a second bridge member pivotally coupled between the second portions of the base members.

5. The main gate roof support of claim 1, wherein the bridge member includes a bracket having an opening positioned adjacent a slot on one of the base members, the bridge being rotatably coupled to the base member by a bolt extending through the opening and the slot.

6. The main gate roof support of claim 1, wherein the sloughing plate extends the entire length of the one base member.

7. The main gate roof support of claim 1, wherein the first portion and the second portion of each base member are separated by a gap, and further comprising a first plate coupled to the first beam and positioned above the gap, and a second plate coupled to the second beam and positioned above the gap adjacent the first plate.

8. The main gate roof support of claim 7, further comprising a third plate coupled to the first beam and positioned above the gap, the third plate laterally spaced apart from the first plate, wherein the second plate is positioned between the first plate and the third plate.

9. The main gate roof support of claim 1, wherein the first shield is pivotally coupled to the first portion by a linkage.

10. A main gate roof support comprising: a first base portion for engaging a ground, the first base portion including a first support leg; a second base portion for engaging the ground and coupled to the first base portion, the second base portion including at least one second support leg; a third base portion for engaging the ground proximate a mine face and coupled to the second base portion, the third base portion including a third support leg; a first shield pivotally coupled to the first base portion; a first beam for engaging a mine roof, the first beam pivotally coupled to the first shield and coupled to the first support leg; a second beam for engaging the mine roof, the second beam pivotally attached to the first beam and coupled to the at least one second support leg; and a third beam for engaging the mine roof proximate a mine face, the third beam pivotally coupled to the second beam and coupled to the third support leg, wherein the first base portion, the second base portion, and the third base portion are defined by a first pontoon and a second pontoon spaced apart from the first pontoon, wherein the first beam, the second beam, and the third beam each span across the first pontoon and the second pontoon, further comprising a first bridge pivotally coupled between the first pontoon and the second pontoon, the first bridge including a leg, each of the pontoons including a pocket configured to receive the leg, the leg being rotatably supported in one of the pockets; and further comprising a second bridge pivotally coupled between the first pontoon and the second pontoon.

11. The main gate roof support of claim 10, wherein the pontoons are movable relative to each other.

12. The main gate roof support of claim 10, further comprising a sloughing plate coupled to at least one side of the main gate roof support, the sloughing plate extending at least partially between the first base portion and the first beam.

13. The main gate roof support of claim 10, wherein the first, second, and third support legs are extendable by a hydraulic actuator.

14. A main gate roof support comprising: two spaced apart pontoons, each pontoon including a hydraulically operable rearward support leg, a hydraulically operable forward support leg, and at least one hydraulically operable middle support leg; a rearward shield pivotally coupled to the pontoons by at least one rearward linkage; a rearward bridge pivotally coupled to each of the pontoons; a rearward roof-engaging beam pivotally coupled to the shield; the rearward roof-engaging beam coupled to the pontoons by the rearward support legs; a middle roof-engaging beam pivotally coupled to the rearward roof-engaging beam, the middle roof-engaging beam coupled to the pontoons by the at least one middle support legs; a middle bridge pivotally coupled to each of the pontoons; a forward roof-engaging beam pivotally coupled to the rearward roof-engaging beam, the forward roof-engaging beam coupled to the pontoons by the forward support legs; a forward bridge pivotally coupled to each of the pontoons; and a sloughing plate coupled to at least one of the pontoons.

15. The main gate roof support of claim 14, wherein each bridge includes a leg that is received in a pocket on one of the pontoons, each leg being rotatably coupled to the pocket.

16. The main gate roof support of claim 14, wherein the pontoons are movable relative to one another.

17. A longwall mining system comprising: a main gate roof support including a pair of elongated base members laterally spaced apart from one another, each base member including a first portion, a second portion, a first support pivotally coupled to the first portion, and a second support pivotally coupled to the second portion, a first shield pivotally coupled to the first portion of each base member, a first beam coupled to the first portions of the base members by the first supports, the first beam pivotally coupled to the shield, a second beam coupled to the second portions of the base members by the second supports, and a bridge member pivotally coupled between each of the base members; a face end roof support positioned adjacent the main gate roof support, the face end support including a rear base, a rear shield pivotally connected to the rear base by a rear linkage, a rear beam for engaging the roof, the rear beam pivotally attached to the shield, a pair of spaced-apart rear support legs connected between the rear base and the rear beam, a forward base, a forward shield pivotally connected to the forward base by a forward linkage, a forward beam for engaging the roof, the forward beam pivotally connected to the rear beam, and a pair of spaced apart forward support legs connected between the forward base and the forward beam; a forward conveyor including a forward conveyor drive pivotally connected the forward base of the face end roof support; and a rear conveyor including a rear conveyor drive pivotally connected to the rear base of the face end roof support.

18. The longwall mining system of claim 17, wherein the bridge member includes a leg that is received in a slot on one of the base members such that the bridge is rotatable relative to the base member.

19. The longwall mining system of claim 17, wherein the base members of the main gate support further includes a third portion positioned between the first portion and the second portion, a third support pivotally coupled to the third portion, and a third beam for engaging the roof, the third beam pivotally coupled to the first beam and pivotally coupled to the second beam.

20. The longwall mining system of claim 17, wherein the main gate support further includes a sloughing plate pivotally coupled to one of the base members and extending at least partially between the base member and the first beam.

21. The longwall mining system of claim 17 further comprising: at least one near end roof support adjacent the face end roof support, the near end roof support having a longitudinal length substantially shorter than a longitudinal length of the face end roof support; and at least one face roof support adjacent the near end roof support, the face roof support having a longitudinal length substantially shorter than the longitudinal length of the near end roof support, wherein the forward conveyor is connected to the at least one near end roof support and the at least one face roof support, and wherein the rear conveyor is connected to the at least one near end roof support and the at least one face roof support.

Description

DESCRIPTION OF DRAWINGS

(1) FIG. 1 is a side view of a conventional roof support.

(2) FIG. 2 is a side view of a conventional tailgate end roof support.

(3) FIG. 3 is a perspective view of a conventional main gate roof support.

(4) FIG. 4A is a schematic perspective view of a prior art longwall mining method known as an advancing longwall. FIG. 4B is a top schematic view of the prior art longwall advancing mining method shown in FIG. 4A.

(5) FIG. 5 is a top schematic view of a longwall mining system according to this disclosure.

(6) FIG. 6 is a schematic perspective view of the longwall mining system shown in FIG. 5.

(7) FIG. 7A is a side view of a conventional top coal caving face roof support. FIG. 7B is a side view of a near end roof support according to this disclosure. FIG. 7C is a side view of a end face roof support according to this disclosure.

(8) FIG. 8 is a side view of a longwall main gate roof support assembly according to this disclosure.

(9) FIG. 9A is a top view of the longwall main gate face support shown in FIG. 8. FIG. 9B is an end view of the longwall main gate roof support assembly shown in FIG. 8.

(10) FIG. 10 is an unassembled perspective view of the legs of the bridge portion of the main gate roof support assembly shown in FIG. 8.

(11) FIG. 11 is a schematic perspective view of the main gate roof support assembly shown in FIG. 8, without a sloughing plate.

(12) FIG. 12A is an alternate embodiment of the main gate roof assembly shown in FIG. 11. FIG. 12B is a perspective view of the main gate roof support assembly shown in FIG. 12A, with the roof support assembly shown in a web-advanced position.

(13) Before one embodiment of the disclosure is explained in detail, it is to be understood that the disclosure is not limited in its application to the details of the construction and the arrangements of components set forth in the following description or illustrated in the drawings. The disclosure is capable of other embodiments and of being practiced or being carried out in various ways. Also, it is to be understood that the phraseology and terminology used herein is for the purpose of description and should not be regarded as limiting. Use of including and comprising and variations thereof as used herein is meant to encompass the items listed thereafter and equivalents thereof as well as additional items. Use of consisting of and variations thereof as used herein is meant to encompass only the items listed thereafter and equivalents thereof Further, it is to be understood that such terms as forward, rearward, left, right, upward and downward, etc., are words of convenience and are not to be construed as limiting terms.

BEST MODE

(14) FIG. 5 is a schematic illustration of various roof supports that make up a longwall system according to this disclosure. The longwall mining system 200 includes at least one face end cantilevered roof support 204, a near end cantilevered roof support 208 adjacent the face end roof support 204, and at least one conventional face cantilevered roof support 212 adjacent the near end roof support 208. More particularly, in the illustrated embodiment, the longwall system includes three face end roof supports 204, one near end roof support 208, and at least one roof support 212. Several of the roof supports 212 typically present beside the roof support 212 are not shown, but are understood to be present. A main gate roof support 216 is also present, adjacent the longwall system end with the three face end supports 204.

(15) In the illustrated embodiment of FIG. 5, the face end roof support 204 has a longitudinal length 205, and the near end roof support 208 has a longitudinal length 209 substantially shorter than the face end roof support longitudinal length 205. The face roof support 212 also has a longitudinal length 213, and it is substantially shorter than the near end roof support longitudinal length 209. This creates an effective cave line 211 at an angle to the coal face, that helps reduce the goaf pressure on the face end, thereby increasing the stability of the main gate roof support 216.

(16) A perspective schematic view of the roof supports is illustrated in FIG. 6, showing forward armored face conveyors 211, and rearward armored face conveyors 220. FIGS. 7A, 7B and 7C illustrate side views of the three different kinds of face end supports shown in FIG. 4. The conventional face support 212 is shown in FIG. 7A, and is essentially the same as that described in connection with FIG. 1, only with the addition of a tailpiece 218 that covers the rearward armored conveyor 220. In FIG. 7B is the near end roof support 208, and in FIG. 7C is the face end support 204, according to this disclosure.

(17) FIG. 8 is a side view of the main gate roof support 216. The main gate support is similar to a conventional main gate support, but with a couple of important differences. As in the conventional support, the main gate support includes at one pair of separate but adjacent floor-engaging bases or pontoons 230 and 232 (see FIGS. 9A and 9B). Each of the pontoons 230 and 232 carries a support leg 234 and 234 (see FIG. 8) that is pivotally attached to the pontoon and pivotally attached to a roof roof-engaging beam. Unlike in the conventional main gate support, the two adjacent but spaced apart pontoons 230 and 232 support a single roof roof-engaging beam system 240 (see FIGS. 9B and 11) that spans both of the pontoons 230 and 232. In order to permit up and down movement of the pontoons 230 and 232 relative to each other, but to keep the pontoons adjacent to one another in the forward and reward movement directions, a pivotally attached bridge 244 spans the pontoons 230 and 232.

(18) More particularly, the bridge 244 extends across the front of the pontoons, midway along the pontoons, and across the rear of the pontoons, as shown in FIGS. 8 and 9A. Each bridge 244 is attached to each pontoon at a joint 250, as shown in FIG. 10. More particularly, the bridge 244 is pivotally connected to each pontoon (for example, pontoon 230) by the rigid joint 250, and this joint 250 maintains the adjacent pontoons in side-by-side relationship, while at the same time permitting up and down movement of the pontoons relative to each other. Still more particularly, each end of the bridges 244 includes a leg or male member 254 received in a female member or pocket 270 attached to a pontoon. The pocket 270 comprises two spaced apart rigid plates 262 and 268, and two spaced apart walls 272 and 276, that extend perpendicular to the plates 262 and 268, and between the plates 262 and 268. The combination of the plates and walls form the pocket 270 that receives the bridge leg 254. An opening 280 extends through the joint walls 272 and 276, and a corresponding opening 284 in the bridge leg 254 aligns with the openings 280 in the joint walls when the bridge leg 254 is received in the pocket 270. A bolt 288 is provided for extending through the openings 280 and 284 securing the bridge leg 254 within the pocket 270. Means for securing the bolt 288 in the pocket 270 in the form of a Cotter pin 290 is provided at the end of the bolt 288 to secure the bolt 288 in the joint 250. When received in the pocket 270, the leg 254 is spaced apart from the pontoon 230, so that the leg 254 can rotate about the bolt 288 in the pocket 270.

(19) A jointed sloughing plate 294 (see FIG. 8) attached to the outward pontoon of the main gate roof support 216, and away from the other roof supports, provides a further enhancement. The sloughing plate extends the full-length of the main gate roof support 216, and provides extra protection to the roadway.

(20) Turning now to the details of the various roof supports shown in FIGS. 5 through 10, the face end roof support 204 includes a rearward floor-engaging base 300, a rearward shield 304, a rearward roof-engaging beam 308 pivotally attached to the shield 304, and two spaced apart hydraulically operable rearward support legs 312 (only one is shown) connected between the rearward floor-engaging base 300 and the rearward roof-engaging beam 308. The face end roof support further includes rearward linkage 316 pivotally connecting the rearward shield 304 to the rearward base 300, a forward floor-engaging base 320, a forward shield 324, and a forward roof-engaging beam 328 pivotally connected to the rearward roof-engaging beam 308. Four spaced apart hydraulically operable forward support legs spaced apart in pairs 332 and 333 forward and rearward are connected between the forward floor-engaging base 320 and the forward roof-engaging beam 328, and cantilevered linkage 336 pivotally connects the rearward shield 324 to the forward base 320.

(21) The near end cantilevered roof support 208 includes a floor-engaging base 340, a shield 344, a roof-engaging beam 348 pivotally attached to the shield 344, and four spaced apart hydraulically operable forward support legs 352 connected between the floor-engaging base 340 and the roof-engaging beam 348. The near end roof support 208 also includes cantilevered linkage 356 pivotally connecting the shield 344 to the base 340, and two spaced apart hydraulically operable rearward support legs 353 connected between the floor-engaging base 340 and the roof-engaging beam 348. The rearward support legs 364 are spaced apart from the two spaced apart hydraulically operable forward support legs 352.

(22) The near end roof support 208 also includes a rearward conveyor drive 370 pivotally connected to the floor-engaging base 340, the floor-engaging base 340 being pivotally connected to the rearward conveyor drive 370, and a forward conveyor drive 374, the floor-engaging base 340 also being pivotally connected to the forward conveyor drive 374. The near end roof support also includes a short pivoting roof-engaging beam or tailpiece 380 at the rear of the unit.

(23) The face support comprises a floor-engaging base 384, a shield 388, a roof-engaging beam 392 pivotally attached to the shield 388, and two spaced apart hydraulically operable support legs 396 (only one is shown) connected between the floor-engaging base 384 and the roof-engaging beam 392. Cantilevered linkage 398 pivotally connects the shield 388 to the base 384.

(24) The main gate roof support 216 includes two spaced apart sides 500 and 504 (see FIG. 9B), with each side comprising a rearward floor-engaging base 508, a hydraulically operable rearward support leg 234 connected to the rearward floor-engaging base 508, and a rearward shield 516. Rearward cantilevered linkage 520 pivotally connects the rearward shield 516 to the rearward base 508. A middle floor-engaging base 524 is connected to the rearward floor-engaging base 508, and hydraulically operable middle support legs 528 are connected to the middle floor-engaging base 524. A forward floor-engaging base 530 is pivotally connected to the middle floor-engaging base 524, and a hydraulically operable forward support leg 234 is connected to the forward floor-engaging base 530.

(25) The main gate roof support 216 further includes a rearward roof-engaging beam 540 pivotally attached to the rearward shield 516, and the spaced apart hydraulically operable rearward support legs 234 of the sides are connected between the rearward floor-engaging bases 508 and the rearward roof-engaging beam 540. A middle roof-engaging beam 550 is pivotally connected to the rearward roof-engaging beam 540, and the spaced apart hydraulically operable middle support legs 528 of the sides are connected between the middle floor-engaging bases 524 and the middle roof-engaging beam 550. A forward roof-engaging beam 560 is pivotally attached to middle roof-engaging beam 550, and the spaced apart hydraulically operable forward support legs 234 of the sides are connected between the forward floor-engaging bases 530 and the forward roof-engaging beam 560. The forward, middle and rearward floor-engaging bases of each side combine to form each of the pontoons of the main gate support 216.

(26) In an alternate main gate roof support assembly 400, as shown in FIGS. 12A and 12B, a first cantilevered roof support 404 includes two spaced apart sides, with each side having a first floor-engaging base 408, a first shield 412, a first roof-engaging beam 416 pivotally attached to the first shield 412, and a first hydraulically operable support leg 420 connected between the first floor-engaging base 408 and the first roof-engaging beam 416. The first cantilevered roof support 404 also includes a first cantilevered linkage 420 pivotally connecting the first shield 412 to the first base 408. Facing the first roof support 404 is a second cantilevered roof support 424 including a second floor-engaging base 428, a second shield 432, and a second roof-engaging beam 436 pivotally attached to the second shield 432. The second roof-engaging beam 436 is adjacent the first roof-engaging beam 416 and interspersed within the first roof-engaging beam 416. A second hydraulically operable support leg 440 is connected between the second floor-engaging base 428 and the second roof-engaging beam 436, and a second cantilevered linkage 444 is pivotally connecting the second shield 428 to the second base 428. In the illustrated embodiment, another hydraulic hydraulically operable support leg is also connected between the second floor-engaging base 428 and the second roof-engaging beam 436. The roof-engaging beams and shields of each side of the roof supports 404 and 424 are integral plates that span and are connected to both sides of the roof supports.

(27) More particularly, the first roof-engaging beam 416 comprises two spaced apart plates 450, and the second roof-engaging beam 436 comprises a plate 454 positioned between the first roof-engaging beam spaced apart plates 450. By virtue of being separate, not connected roof supports 404 and 424, the main gate roof support assembly 400 can advance one roof support, and then advance the other, to aid the longwall mining process.

(28) Various other features and advantage of the invention are set forth in the following claims.