CONTINUOUS-EXTRACTION MINING SYSTEM
A material extraction system for an underground mine includes a mobile sizer for sizing removed material, an elevated bunker operable to collect the sized material, and a shuttle car operable to receive the collected material from the elevated bunker. The shuttle car is positioned substantially below the elevated bunker for receiving the collected material from the elevated bunker.
In underground hard-rock mining, a process called block caving can be used. In this process, an ore body is typically preconditioned by fracturing the ore via various methods, e.g., hydro-fracturing. Conical or tapered voids are then drilled at the bottom of the ore body, and the void is blasted. The fractured ore body above the blast will cave, and, through gravity, fall or settle down into collection areas called draw-bells. The draw-bells serve as discharge points to an entryway. Load-haul-dump vehicles typically tram through the entryway to load ore from the draw-bell. The vehicles haul the ore through various other entryways to a centrally-located dump point and dump the ore into an underground crusher that has been installed at the dump point. The crushed ore subsequently is fed to a conveyor system to be conveyed out of the mine. As additional ore is removed from the draw-bells, the ore body caves in further, providing a continuous stream of ore.
SUMMARYIn some embodiments, a material extraction system for an underground mine includes a mobile sizer for sizing removed material, an elevated bunker operable to collect the sized material, and a shuttle car operable to receive the collected material from the elevated bunker. The shuttle car is positioned substantially below the elevated bunker for receiving the collected material from the elevated bunker.
Other aspects of the invention will become apparent by consideration of the detailed description and accompanying drawings.
Before any embodiments of the invention are explained in detail, it is to be understood that the invention is not limited in its application to the details of construction and the arrangement of components set forth in the following description or illustrated in the following drawings. The invention is capable of other embodiments and of being practiced or of 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 limited. The use of “including,” “comprising” or “having” and variations thereof herein is meant to encompass the items listed thereafter and equivalents thereof as well as additional items. The terms “mounted,” “connected” and “coupled” are used broadly and encompass both direct and indirect mounting, connecting and coupling. Further, “connected” and “coupled” are not restricted to physical or mechanical connections or couplings, and can include electrical connections or couplings, whether direct or indirect.
With continued reference to
In the illustrated embodiment, the feed conveyor 22 is supported by steerable wheels or treads 28 (wheels are shown in
In some embodiments, the mobile sizer 12 may include a funnel or other guide member (not shown) for guiding material from the feed conveyor 22 into the sizer portion 18. One or more cylindrical rollers with associated bits are mounted in the sizer portion 18 and size or crush the material 2. As explained below, the mobile sizer 12 is configured to size or crush the removed material on a substantially continuous basis. The sized material is deposited from the sizer portion 18 onto the discharge conveyor 24 and conveyed upwardly to a position substantially elevated relative to the mine floor. The discharge conveyor 24 can contain portions with different slopes. Some embodiments of the discharge conveyor 24 may also include support legs. The discharge conveyor 24 may be separate from or integral with the mobile sizer 12, and may be driven or powered by its own independent drive system or by the drive system of the mobile sizer 12. The feed conveyor 22 and the discharge conveyor 24 can employ a plate-type conveyor, an armored-face conveyor, an endless-belt type conveyor, or other conveyors that are known in the art.
The elevated bunker 14 collects the sized material from the discharge conveyor 24, and holds the sized material while the shuttle car 16 is tramming between the dump point 11 and the elevated bunker 14. In this regard, the elevated bunker 14 acts as a surge capacitor or buffer for the sized material. Referring also to
In the illustrated embodiment, the collector portion 38 defines a top opening 44 for collecting material from the discharge conveyor 24 and a bottom opening 46 for dumping or dropping the collected material by gravity onto the shuttle car 16. A funnel or chute 48 is coupled to the top opening 44 for guiding the material from the discharge conveyor 24. In some embodiments, the funnel 48 can be omitted. A pair of base members or doors 50 are coupled to the bottom opening 46 for movement relative thereto between a collect configuration (see
Referring to
Referring to
In the illustrated embodiment, the elevated bunker 14 includes no drive mechanisms for tramming along the roadway entries 6, and instead is hitched, towed, pushed, or pulled like a trailer, e.g., by the mobile sizer 12 or a maintenance vehicle (not shown). In other embodiments, the elevated bunker 14 may be powered or driven at least in part by the self-contained power supply or drive mechanism of the mobile sizer 12. In still other embodiments, the elevated bunker 14 may be driven by its own integrated drive system.
Referring also to
The illustrated wheels 56 are engageable with the mine floor, and thus the shuttle car 16 is movable along the roadway entries 6 for transferring the collected material. In other embodiments, the shuttle car 16 may instead comprise rail-car-type wheels for movement over rails. In some embodiments, the shuttle car 16 comprises a chromium carbide overlay plate, which may allow for a relatively thick plating so as to facilitate receiving dense or heavy material.
In operation, while the material is being removed, sized (if necessary), and collected at the draw-bell 4, the shuttle car 16 hauls the collected material to the dump point 11, bottom-dumps the collected material into the dump point 11, and then returns toward the elevated bunker 14. Once the shuttle car 16 is positioned substantially below the elevated bunker 14, the elevated bunker 14 drops the collected material to the shuttle car 16. The shuttle car 16 can then tram backwards toward the dump point 11 for rapidly or quickly dropping the collected material to the dump point 11. The dump point 11 is connected to a sub-level conveyor system to eventually convey the material out of the mine. While the shuttle car 16 is tramming in the fore and aft directions, the mobile sizer 12 of the continuous-extraction system 10 can continue removing and sizing the material. The material thus moves from the mobile sizer 12, to the discharge conveyor 24, to the elevated bunker 14, to the shuttle car 16, and then outside the mine, all on a substantially rapid and continuous basis. After completing an operation at a given draw-bell 4, the legs 40 of the elevated bunker 14 are moved to the retracted position. The continuous-extraction system 10 can then tram backwards until the feed conveyor 22 is once again positioned in the roadway entry 6. Next, the continuous-extraction system 10 trams further along the roadway entry 6 to the next draw-bell entry 9. Once the elevated bunker 14 is positioned at the next draw-bell entry 9, the legs 40 are moved to the extended position, and the material-loading process is repeated. In a block-cave infrastructure 8 with multiple draw-bells 4, a plurality of continuous-extraction systems 10 can be employed to further improve production rates.
By having the mobile sizer 12 positioned within the roadway entry 6 proximal to the draw-bell 4, the amount of time spent tramming by the shuttle car 16 is dramatically reduced compared to known systems that utilize massive, centrally-located underground dump points with large, immovable crusher assemblies. Known systems may also require an infrastructure in the roadway entries 6, such as haulage conveyors or conveyor belts mounted to the mine floor or to one of the walls of the roadway entries, and associated structures. However, haulage conveyors may undesirably limit the available space for maneuvering equipment in the underground roadway entries 6. Moreover, the haulage conveyors are susceptible to fly-rock damage from secondary blasting that occasionally takes place in the draw-bells 4. By utilizing the shuttle car 16, such infrastructure in the roadway entries 6 can be substantially eliminated, while improving production rates.
Because the shuttle car 16 is only required to tram the relatively short distance between the draw-bells 4 and the mobile sizer 12, the shuttle car 16 can be driven or powered at least in part by batteries or a small diesel power unit. In some embodiments, the shuttle car 16 can be powered by a hybrid unit of diesel engine and batteries, where a diesel engine runs to charge the battery, for example between high load demands, between shifts, at break times, and the like. In further embodiments, the shuttle car 16 can be powered through multiple batteries, where one or more batteries are being charged while the others are being used. The batteries, small diesel power unit, or hybrid unit can be used to drive electric and/or electro-hydraulic motors and drive systems. In some embodiments, each wheel 56 of the shuttle car 16 may include its own dedicated electronic drive that comprises, for example, an electric motor and accompanying gearbox. In this way, each wheel can be controlled independently by an associated variable frequency drive system or a chopper drive system, thus reducing or eliminating the need for mechanical transfer cases and differentials.
Some embodiments can also include automation equipment operable to position the continuous-extraction system 10 at draw-bells 4 and to control other movements as needed. For example, remote cameras can be employed to help operate the loading arm 32, move the legs 40 and/or drive treads 42 of the elevated bunker 14, and maneuver and operate the continuous-extraction system 10 into the draw-bell 4 from a remote location. Radio or cable communication links can be used to a similar extent, with or without the remote operation cameras. In some embodiments, an operator for the remote operation cameras, communication links, or both, can be located underground. In other embodiments, the operator can be located above ground. An above ground operator can be many kilometers away from the mine. In yet other embodiments, the continuous-extraction system 10 can contain position-sensing devices for automation, remote operation, or both.
Although the invention has been described in detail with reference to certain preferred embodiments, variations and modifications exist within the scope and spirit of one or more independent aspects of the invention as described. Various features and advantages of the invention are set forth in the following claims.
Claims
1. A bunker comprising:
- a collection portion configured to receive sized material from a sizer unit, and having a bottom opening;
- a base member coupled to the collection portion for movement relative to the bottom opening; and
- a plurality legs coupled to the collection portion, wherein the collection portion is positioned to allow a haulage vehicle to be positioned underneath the collection portion so that sized material can be moved to the haulage vehicle through the bottom opening when the base member moves relative to the bottom opening.
2. The bunker of claim 1, wherein the plurality of legs are telescoping.
3. The bunker of claim 2, wherein each of the plurality of legs is telescopically movable between an extended position and a refracted position.
4. The bunker of claim 3, wherein when each of the plurality of legs are in the extended position, the haulage vehicle is able to fit substantially below the collection portion.
5. The bunker of claim 3, wherein when each of the plurality of legs are in the retracted position, the haulage vehicle is unable to fit substantially below the collection portion.
6. The bunker of claim 1, wherein the plurality of legs are coupled to a plurality of drive treads engageable with a mine floor.
7. The bunker of claim 6, wherein the each of plurality of drive treads are rotatable about a generally vertical axis.
8. The bunker of claim 7, wherein the plurality of drive treads further include a hydraulic suspension.
9. The bunker of claim 1, wherein the base member is movable relative to the bottom opening between a collect position with the bottom opening closed by the base member and a discharge position with the base member at least partially removed from the bottom opening.
10. The bunker of claim 9, wherein an actuator is coupled to the base member to move the base member between the collect position and the discharge position.
11. The bunker of claim 1, wherein the bunker continuously receives sized material from the mobile sizer regardless of the haulage vehicle position.
12. The bunker of claim 1, wherein the bunker includes an integrated drive system.
13. The bunker of claim 1, wherein the haulage vehicle includes a receptacle having a haulage vehicle bottom opening and a base member coupled to the receptacle for movement relative to the haulage vehicle bottom opening.
14. An elevated bunker comprising:
- a collection portion having a bottom opening;
- a base member coupled to the collection portion for movement relative to the bottom opening;
- a plurality of telescoping legs, wherein each of the legs is telescopically movable between an extended position and a retracted position;
- a plurality of drive treads coupled to the plurality of telescoping legs, each of the plurality of drive treads engageable with a floor and rotatable about a generally vertical axis.
15. The elevated bunker of claim 14, wherein the base member is movable relative to the bottom opening between a collect position with the bottom opening closed by the base member and a discharge position with the base member at least partially removed from the bottom opening.
16. The elevated bunker of claim 15, wherein an actuator is coupled to the base member to move the base member between the collect position and the discharge position.
17. The elevated bunker of claim 14, wherein the elevated bunker includes an integrated drive system.
18. The elevated bunker of claim 14, wherein the plurality of drive treads further include a hydraulic suspension.
19. The elevated bunker of claim 14, wherein the collection portion is positioned to allow a haulage vehicle to be positioned underneath the collection portion so the sized material can be moved to the haulage vehicle through the bottom opening.
20. The elevated bunker of claim 19, wherein the haulage vehicle includes a receptacle having a haulage vehicle bottom opening and a base member coupled to the receptacle for movement relative to the haulage vehicle bottom opening.
Type: Application
Filed: Mar 25, 2014
Publication Date: Sep 25, 2014
Inventors: Joseph J. Zimmerman (Franklin, PA), Jared Green (Butler, PA)
Application Number: 14/224,528
International Classification: B65D 88/54 (20060101);