Advancer for coal mining system

Abstract

A mining system for advancing and retrieving a miner and, optionally, material transfer units and shields for the units into and out of mines. The system includes a beam structure with inner and outer beams. One beam is advanced while the other is held stationary. Once the advancing step is complete, the second beam is pulled forward to its original position. This system optionally advances material transfer units into the mine as well. If desired, shields for the units may also be simultaneously advanced into the mine in the same manner. To retrieve the miner, the system is reversed and the miner is pulled from the mine. This process may also be used to retrieve shields or material transfer units.

Description

FIELD OF THE INVENTION

[0002] The invention is generally related to an improved system for coal mining. More particularly, the invention is directed to an advancer for high wall mining.

DESCRIPTION OF RELATED ART

[0003] Highwall mining is generally a method of mining whereby a remote controlled continuous miner is sent into a face of coal, or other ore, from an outside bench to mine or cut such ore out from under the overburden above. The continuous miner will generally cut out the ore in widths ranging from six to twelve feet in width and up to fourteen feet in height, depending on the size of miner used. As the miner is remotely controlled from outside into the ore, units for transferring the mined ore, called “cars” or “beams,” are sequentially sent into the mine, forming a continuous train and transferring the ore from car to car to the outside bench. Various methods are incorporated into the units for transferring the ore, including conveyors, chains and screws. Likewise, various methods are used to power the transferring units, including electrical, hydraulics and/or mechanical drive shafts. The cars or beams are generally either coupled or pinned together, allowing some degree of deflection between them to improve negotiation of the rough surface in the mine.

[0004] On the outside of the mine, a launch platform is positioned to receive the transferred material as it is discharged from the rear car or beam and directs it either to a truck or stockpile via belt conveyors and/or chain conveyors. The launch platform also acts as a staging area to insert and retrieve the cars as needed and as a drive station to either hydraulically, electrically or mechanically drive or push the cars into the mine.

[0005] Additional roof problems are created by not controlling the direction of the miner precisely as it is driven into the mine. If the miner is not steered properly, the pillar or rib in between two mines can be cut. When the system cuts through the pillar exposing the width of two cuts, which can be as much as twelve feet in width each, twenty feet or more of unsupported roof is exposed. This greatly increases the potential for major roof falls, thus increasing the potential for entrapment.

[0006] Systems commonly used today require significant force to push the transfer units and the miner into particularly deep mines. In deep mines, this force often causes the cars to buckle up and down throughout the hole binding. Because of this, the depth to which they can be pushed is limited.

[0007] Current disclosed methods of remote mining in ore deposits such as coal generally employ a mining machine that excavates mine openings to some distance from the seam exposure on the surface and a system for conveying the mined ore to the surface. In most of the present systems, the system for conveying consists of multiple conveyors which are advanced into the mine openings from the surface. U.S. Pat. Nos. 6,644,753 and 6,220,670 issued to Mraz disclose a method and apparatus for mining of aggregate material from a seam which includes a mining apparatus and a self-propelled conveyor capable of advancing or retreating in the seam on its own power and an advancing and steering arrangement for the mining apparatus.

[0008] U.S. Pat. Nos. 5,112,111, 5,232,269, 5,261,729 and 5,364,171 to Addington at al. disclose an assembly of conveyors and a mining machine advanced into the seam without interrupting the flow of aggregate material by separate means designed to pull at the forward end and push at the rearward end. Similarly, U.S. Pat. No. 5,609,397 to Marshall at al. discloses an assembly of conveyors interconnected with a mining machine and a driving device located outside the seam and consisting of rack and pinion or, alternately, reciprocating cylinders, linear tracks, linear or rotary drives, chains, cables or other mechanical devices. U.S. Pat. No. 5,692,807 to Zimmerman discloses a guidance assembly for extending and retracting an assembly of conveyors into and out of the seam. U.S. Pat. No. 3,497,055 to Oslakovic at al. discloses a multi-unit train of conveyors having a self-propelled unit at each end coupled to intermediate units, each end unit being capable of towing the intermediate units. U.S. Pat. No. 2,826,402 to Alspaugh at al. discloses a train of wheeled conveyor sections pulled into the mine opening and pushed out of it by a self-propelled mining machine. Buckling of the train is avoided by the grooves made by the mining machine in the floor, said grooves spaced the same distance as the treads of the wheels carrying the conveyor sections.

[0009] At present, as the interconnected assembly of the mining machine and a plurality of material handling units is advanced some distance into the seam from a launch vehicle located on the outside, the axial force within the assembly becomes excessive with respect to its length and the assembly becomes less rigid. As a consequence, it becomes difficult to steer the mining machine located at the front of the assembly and the conveying assembly itself can become unstable, which limits the penetration depth of mining.

[0010] A unit pulling the plurality of material handling units from within the mine, at the front of the interconnected assembly, would prevent the buckling of the assembly caused by driving the assembly solely from the outside platform, thus allowing deeper penetration. Applying the ability to steer the miner close to the face would allow the miner to be held on the desired course and maintain the desired rib control which could minimize roof falls.

[0011] Because the miner is remote controlled, it is difficult, if not impossible, to keep it on a straight course which is imperative to maintain rib width. The problem is due to the miner crawlers either losing traction or the miner following a pitch to one side or the other. A walking device that has the ability to stabilize itself and correct itself if it gets off course, could be used in addition to or in lieu of the miner crawlers.

[0012] Accordingly, it is an object of the present invention to provide an improved system for advancing material transfer units for mined material into and out of mines.

[0013] It is another object of the present invention to provide an improved system for advancing shielded or unshielded material transfer units into and out of mines.

[0014] It is another object of the present invention to provide a system for removing a miner and/or material transfer units from within a mine in the event they become entrapped.

[0015] It is another object of the present invention to provide an improved mining system which reduces or eliminates down time caused by falling rocks or cave-ins.

[0016] It is a further object of the present invention to provide an improved mining system which provides increased control of the transfer units at greater mine depths.

[0017] It is yet a further object of the present invention to provide an improved mining system which provides greater directional control of the miner and transfer units.

[0018] Finally, it is an object of the present invention to accomplish the foregoing objectives in a safe and cost effective manner.

SUMMARY OF THE INVENTION

[0019] A mining system for advancing mining equipment into mines, includes two beams, one slidably disposed within the other, an advancing means for advancing the beams independently, at least one actuating means connected to the beam structure and a gripping means attached to and actuated by the actuating means. The beams are preferably rectangular in cross section and constructed from a heavy duty material appropriate for use in the mining industry such as steel. The outer beam has at least one opening for the actuating means. The advancing means for the beams is preferably a hydraulic cylinder which propels the outer beam as it extends and pulls the inner beam as it retracts. The actuating means for the gripping means is preferably at least a pair of cylinders and more preferably, three pairs of cylinders which actuate gripping means to grip the roof, floor and walls of the mine. The gripping means is preferably a plate connected to the cylinders and more preferably, plates for gripping the roof, floor and wall of the mine.

BRIEF DESCRIPTION OF THE DRAWINGS

[0020] FIG. 1 is end view of preferred embodiment of the present invention with wall, brace, steer cylinders extended into wall;

[0021] FIG. 2 is end view of the preferred embodiment of the present invention with wall brace, steer cylinders retracted;

[0022] FIG. 3 is a cross section side view of advancer with all cylinders in retracted position;

[0023] FIG. 4 is cross section of one side of the advancer with floor, roof and wall/brace/steer cylinders extended;

[0024] FIG. 5 is cross section of one side of the advancer with floor, roof and wall/brace/steer cylinders extended creating resistance and outer tube being pushed forward;

[0025] FIG. 6 is cross section of one side of the advancer with floor, roof and wall/brace/steer cylinders extended and outer tube extended full stroke of cylinders;

[0026] FIG. 7 is cross section of one side of the advancer with floor, roof and wall/brace/steer cylinders retracted and ready for push cylinder to retract pulling the inner tube forward;

[0027] FIG. 8 shows an additional set of push cylinders in rear of advancer inner tube for retreating;

[0028] FIG. 9 shows an expanded view of the cylinders with grip plates and pockets within the outer tube for pass by when outer tube is advanced forward or retreating in reverse;

[0029] FIG. 10 is a side view of a typical continuous underground miner using crawlers;

[0030] FIG. 10 a is a plan view of a typical continuous underground miner;

[0031] FIG. 11 is a side view of a continuous underground miner with the advancer installed for tramming and sumping effort instead of crawlers; and

[0032] FIG. 11 a is a plan view of a continuous underground miner showing position of the advancer.

[0033] Element List

[0034] 300 Miner

[0035] 900 First shield/advancer

[0036] 905 Rollers

[0037] 907 Advancer side-frame

[0038] 911 Wall-brace-steer grip plate

[0039] 913 Wall-brace-steer cylinder

[0040] 915 Top plate

[0041] 916 Roof grip plate

[0042] 917 Roof stab cylinders

[0043] 918 Floor grip plate

[0044] 919 Floor stab cylinders

[0045] 921 Advance cylinders

[0046] 923 Outer beam

[0047] 925 Inner beam

[0048] 927 Reverse cylinder

[0049] 929 Reverse cylinder plate

[0050] 931 Slide opening for 913 cylinder

[0051] 933 Slide opening for 919 cylinder

[0052] 935 Slide opening for 917 cylinder

[0053] 950 Continuous underground miner crawlers

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

[0054] Referring now to the drawings, FIGS. 1-9 and 11 show several embodiments of the present invention. As shown, the invention can be used with different types of material transfer units, shielded or unshielded, all capable of being driven into or pulled from a mine. While the preferred embodiment is specifically described for a shielded material transfer unit, the invention is clearly applicable to material transfer units used without shields.

[0055] FIG. 1 shows an end view of the advancer/first shield 900 structured around the miner body 300 with rollers 905 on the sides and top between the advancer 900 and the miner 300. The rollers 905 will allow the miner 300 to be pulled through the advancer structure and then out from within the shielded cars to an external platform in the event of a roof fall thus preventing entrapment of the miner 300. The advancer 900 is made up of two beams or tubes (box beams); one slightly smaller inner beam 925 slides independently within an outer beam 923 allowing a stroke or number of advancing strokes equal to the sump stroke of the miner 300. For example, the advancer 900 can have a stroke or advance of four feet equal to the four foot sump of a Fairchild Continuous miner. The inner beam 925 contains a number of cylinders 913, 917, 919 that, when extended, pass through openings 931, 933, 935 in the outer beam 923 and press plates 911, 916, 918 into any combination of floor, roof, and sidewalls to exert resistance while another set of cylinders 921 pushes the outer beam 923 the stroke required to advance.

[0056] FIG. 1 shows an end view of the advancer 900 with the wall-brace-steer cylinder 913 extended, pushing plate 911 against the sidewall of the mine.

[0057] FIG. 2 shows an end view of the advancer 900 with the wall-brace-steer cylinder 913 in the retracted position.

[0058] FIGS. 3-7 show cross-sectional views inside the inner beam 925 showing the advancing stages taking place.

[0059] FIG. 3 shows all three sets of hydraulic stab cylinders 913, 917, 919 in the retracted position and the push cylinder 921 in the retracted position. The outer beam 923 is provided with openings 931, 933, 935 through which the three sets of cylinders 913, 917, 919 act to engage with the stab plates 911, 916, 918. The openings 931, 933, 935 are elongated to allow the outer beam 923 to slide past the stabbed (extended) plates 911, 916, 918 during the advance/retreat stroke.

[0060] FIG. 4 shows the three sets of stab cylinders 913, 917, 919 in the extended position. The roof stab cylinders 917 can be extended further depending on roof height. The wall-brace-steer cylinders 913 are extended as in FIG. 1. Push cylinder 921 is in the retracted position. Both sides of the advancer 900 work in unison during normal advancing/retreating, however, any cylinder can work independently or in combination with one or more other cylinders. For example, if the entire system must be moved in a lateral direction, only one wall-brace-steer cylinder 913 would be extended to push the system over to the course desired.

[0061] FIG. 5 shows cylinder 921 being extended while the hydraulic stab cylinders 913, 917, 919 are extended, creating resistance by acting on the grip plates 911, 916, 918.

[0062] FIG. 6 shows cylinder 921 in the full extended position, having pushed outer beam 923 the desired stroke.

[0063] FIG. 7 shows the hydraulic stab cylinders 913, 917, 919 retracted through openings 931, 933, 935 in the outer beam 923 such that they are within the outer beam 923 and shows cylinder 921 retracting the inner beam 925 up the distance of the stroke into the position shown in FIG. 3, ready to advance forward another cycle. To retreat out of the mine, the process is reversed.

[0064] If desired, shielded or unshielded cars can be attached to the rear of the advancer 900. As the advancer 900 advances forward, it pulls an entire train of shielded cars forward with it into the mine. The advantage provided by using the advancer 900 to advance all shielded or unshielded cars forward from inside at the miner 300 end is that the buckling caused by other systems is prevented.

[0065] The advancer 900 can also work independently with a miner 300 and/or a surge feeder behind the miner 300 to help advance either or both. It can be structured around the surge feeder moving it forward and in reverse and allowing a platform to push from outside the mine to help the miner 300 during the miner's sump forward.

[0066] FIG. 8 shows an additional set of cylinders 927 within the advancer 900 pushing in reverse against a plate 929 that provides more thrust in reverse rather than working off the weak end of the advance cylinder 921.

[0067] FIG. 9 shows an expanded view of the hydraulic stab cylinders 913, 917, 919 showing gripper plates 918, 916 on the ends of the floor stab cylinders 919 and roof stab cylinders 917. Also, shown is an opening 933 in the bottom of the outer beam 923 for the floor stab cylinder 919 to pass along, opening 931 in the side for wall-brace-steer cylinder 913 to pass along and opening 935 on top of the outer beam 923 for the cylinders 917 to pass along, during the stroke of the cylinder 921 which pulls everything behind forward.

[0068] FIG. 10 shows a side view of a typical underground continuous miner 300 with crawlers 950 that are used to tram the miner 300 into the mine and used to apply force to sump the cutter drum into the seam being cut. FIG. 10a is a plan view of the miner 300 shown in FIG. 10.

[0069] FIG. 11 shows a side view of a continuous underground miner 300 with the advancer 900 installed for tram and sump instead of the crawlers 950 commonly used as shown in FIG. 10. The side view shows the advancer 900 installed on either side of the miner 300 with the wall-brace-steer grip plate 911 showing and the side opening 931 for cylinder 913 shown. FIG. 11a is a plan view of a typical underground continuous miner 300 showing the advancer 900 installed on either side instead of the crawlers 950 normally used. Also shown are the roof grip plates 916 and the side openings 935 for the roof stab cylinders 917. The advancer 900 can use any combination of wall-brace-steer cylinders 913, roof stab cylinders 917, or floor stab cylinders 919 to stabilize itself to walk rather than tram, either forward or reverse. The advancer 900 will provide improved traction in bad floor conditions and also provide greater sump effort for pushing the cutting head of the miner 300 into the material being cut.

[0070] FIGS. 1-9 and 11 show preferred embodiments of the present invention. Although the inner 925 and outer 923 beams are shown as being rectangular in cross section, alternate shapes are within the scope of this invention. Further, the preferred embodiment is shown with grip plates 916, 918 for gripping the mine surfaces. Other means for gripping the mine surfaces are contemplated within the scope of this invention. For example, wedges or spikes could be used. Any gripping means which retains the position of the inner beam 925 while the outer beam 923 is advanced is acceptable.

[0071] While the description above refers to particular embodiments of the present invention, it will be understood that many modifications may be made without departing from the spirit thereof. The accompanying claims are intended to cover such modifications as would fall within the true scope and spirit of the present invention.

Claims

1. An apparatus for advancing mining equipment into mines, comprising: an outer beam; an inner beam slidably disposed within the outer beam to form a beam structure; an advancing means for advancing the outer beam and inner beam independently; at least one actuating means connected to the beam structure; and a gripping means attached to and actuated by the actuating means.

2. The apparatus as set forth in claim 1 wherein the beam structure is substantially rectangular in cross section.

3. The apparatus as set forth in claim 1 wherein the beam structure is constructed from steel.

4. The apparatus as set forth in claim 1 wherein the outer beam includes at least one opening through which the actuating means can extend.

5. The apparatus as set forth in claim 1 wherein the advancing means is a hydraulic cylinder.

6. The apparatus as set forth in claim 5 wherein the cylinder propels the outer beam as it extends and pulls the inner beam as it retracts.

7. The apparatus as set forth in claim 1 wherein the actuating means is at least one pair of cylinders.

8. The apparatus as set forth in claim 1 wherein the actuating means comprises: one pair of roof stab cylinders; one pair of floor stab cylinders; and one pair of wall steer cylinders.

9. The apparatus as set forth in claim 7 wherein the gripping means is a plate connected to each cylinder.

10. The apparatus as set forth in claim 8 wherein the gripping means comprises; a roof grip plate connected to each roof stab cylinder; a floor grip plate connected to each floor stab cylinder; and a wall steer grip plate connected to each wall steer cylinder.

11. The apparatus as set forth in claim 1 wherein the mining equipment is selected from the group consisting of a miner, a material transfer unit and a shield.