The present disclosure relates generally to a bucket assembly for a dragline excavator and more specifically, relates to a linkage assembly for the bucket assembly.
Dragline excavators are utilized in mining operations, such as for removing overburden above a seam or for depositing of a material. The dragline excavators typically use a bucket that is dragged across the ground to perform these operations. Operation of the bucket is controlled by means of hoist and drag machineries, which are controlled by an operator in an operator cabin. Hoist machinery is coupled to the bucket with a hoist chain that is mounted on lateral sidewalls of the bucket. These hoist chains may interfere and hit the sidewalls of the bucket when the bucket moves during operation. It is commonly known to use spreader bar for preventing the hoist chains from hitting the sidewalls of the bucket. However, these spreader bars are susceptible to damage from the bucket body and their maintenance is very expensive. Additionally, these spreader bars add to the weight of the bucket which is not desirable.
U.S. Pat. No. 1,448,212 (hereinafter referred to as '212 patent) relates to a dragline excavator having a supporting cable, a carriage travelling thereon, a stop for the carriage and an excavating bucket swingingly suspended on the carriage. A dumping means is provided on the carriage for dumping the bucket. A draw cable is operatively attached to the bucket and the dumping means. The draw cable is arranged to dump the bucket forcibly by tension on the draw cable when the carriage encounters the stop.
In one aspect, a dragline bucket assembly is provided. The dragline bucket assembly includes a main body, and a linkage assembly for coupling a hoist chain to the main body. The main body includes a lateral sidewall that has a top edge and a bottom edge. The linkage assembly includes a pivot attachment point provided on the lateral sidewall at a first distance from the top edge. The linkage assembly further includes an elongated link member having a first longitudinal end and a second longitudinal end spaced apart from the first longitudinal end by a length greater than the first distance. The first longitudinal end is pivotally coupled to the lateral sidewall at the pivot attachment point and the second longitudinal end is attached to the hoist chain.
In another aspect, a dragline bucket assembly is provided. The dragline bucket assembly includes a main body, and a linkage assembly for coupling a hoist chain to the main body. The main body includes a lateral sidewall that has a top edge and a bottom edge. The linkage assembly includes a pivot attachment point, a rail and an elongated link member. The pivot attachment point is provided on the lateral sidewall at a first distance from the top edge. The elongated link member having a first longitudinal end and a second longitudinal end spaced apart from the first longitudinal end by a length greater than the first distance. The first longitudinal end is pivotally coupled to the lateral sidewall at the pivot attachment point and the second longitudinal end is attached to the hoist chain. The elongated link member further includes a roller provided between the first longitudinal end and the second longitudinal end. The roller is configured to slidably engage with the rail.
In a yet another aspect, a dragline excavator is provided. The dragline excavator includes a housing that includes a hoist machinery and a drag machinery. A hoist chain is coupled to the hoist machinery and a drag chain is coupled to the drag machinery. The dragline excavator further includes a bucket assembly having a main body, and a linkage assembly for coupling the hoist chain to the main body. The main body includes a lateral sidewall that has a top edge and a bottom edge. The linkage assembly includes a pivot attachment point, a rail and an elongated link member. The pivot attachment point is provided on the lateral sidewall at a first distance from the top edge. The elongated link member having a first longitudinal end and a second longitudinal end spaced apart from the first longitudinal end by a length greater than the first distance. The first longitudinal end is pivotally coupled to the lateral sidewall at the pivot attachment point and the second longitudinal end is attached to the hoist chain. The elongated link member further includes a roller provided between the first longitudinal end and the second longitudinal end. The roller is configured to slidably engage with the rail.
Wherever possible, the same reference numbers will be used throughout the drawings to refer to same or the like parts.
The machine 100 operates to remove overburden and/or to deposit material through use of the bucket assembly 104. The bucket assembly 104 may be dragged across a digging path by, taking up and paying out of, one or more hoist ropes 117 (including one or more hoist chains 118) and drag ropes 119 (including one or more drag chains 120) associated with hoist and drag machineries (not shown) of the machine 100, respectively. For example, winding and unwinding of the hoist ropes 117 around a hoist drum (not shown) lifts and lowers the bucket assembly 104 in order to position the bucket assembly 104 at a desired digging location. The drag ropes 119 drag the bucket assembly 104 across the digging path to fill the bucket assembly 104 with the material. The bucket assembly 104 may then be raised and rotated to release the overburden at a desired location. The detailed construction and operation of the hoist and drag machineries are well known in the art and hence not included herein for the sake of brevity of the disclosure.
The main body 202 further includes a first lateral sidewall 210 and a second lateral sidewall 212 (hereinafter collectively referred to as the lateral sidewalls (210, 212)). A rear wall 214 and a bottom wall 216 extend between the first lateral sidewall 210 and the second lateral sidewall 212, as shown, to form the box like structure of the bucket assembly 104. Each of the lateral sidewalls 210, 212 include an inner surface 218 and an outer surface 220 (only one side shown in
Referring to
As illustrated, the first lateral sidewall 210 includes a top edge 302 and a bottom edge 304 longitudinally spaced apart from each to define a height H of the first lateral sidewall 210. In an embodiment of the present disclosure, the top edge 302 may be inclined to have a rear edge 303 positioned relatively higher with respect to a front edge (not shown) of the top edge 302. Further, the linkage assembly 222 includes a pivot attachment point 306 provided on the first lateral sidewall 210 and the elongated link member 224. For example, the pivot attachment point 306 is provided at a distance D from the top edge 302 of the first lateral sidewall 210. In an embodiment, as shown in the figures, the rear edge 303 may be considered as the top edge 302 and the distance D corresponds to the diagonal distance between the pivot attachment point 306 and the rear edge 303.
The elongated link member 224 includes a first longitudinal end 402 and a second longitudinal end 404 (as shown in
In an embodiment of the present disclosure, the length L of the elongated link member 224 is greater than the distance D of the pivot attachment point 306 from the top edge 302 of the first lateral sidewall 210. Referring back to
In an embodiment, the linkage assembly 500 includes the pivot attachment point 306, the elongated link member 224 having a roller assembly 602 (shown in
In an example, the side rail assembly 502 may include a sub rail 504, affixed to the outer surface 220 of the first lateral sidewall 210, and a rail 506 mounted on the sub rail 504. For example, the sub rail 504 may be welded and/or fastened to the first lateral sidewall 210. The added mass of the sub rail 504 provides a strength to the first lateral sidewall 210. The sub rail 504 has a first end 508, a second end 510 and a cavity 512 extending between them. In an exemplary embodiment, the cavity 512 has a rectangular cross-section and is configured to receive the rail 506 therein (as shown in
In an embodiment, the rail 506 has a rectangular cross-section, such that at least a portion of the rail 506 is seated inside the cavity 512 of the sub rail 504 (as shown in
According to an embodiment of the present disclosure, the roller assembly 602 is configured to be disposed in center of the elongated link member 224 between the first longitudinal end 402 and the second longitudinal end 404. However, positioning of the roller assembly 602 is also exemplary and can be varied based on the positioning of the pivot attachment point 306, the side rail assembly 502 and the length L of the elongated link member 224. The roller assembly 602 may include a roller housing 604 configured to encase a shaft or a bush on which a roller 606 rotates. The roller assembly 602 is configured to be mounted in a pocket (not shown) formed in the elongated link member 224. In an embodiment, the roller housing 604 is fastened to the elongated link member 224, by using one or more fasteners 608. It may be well contemplated that any other coupling mechanisms conventionally known in the art may also be used to couple the roller assembly 604 to the elongated link member 224.
The roller 606 of the roller assembly 602 engages with the rail 506 of the side rail assembly 502 (as shown in
As the machine 100 operates, the bucket assembly 104 is moveable about the pivot attachment point 306 between a digging orientation and a dumping orientation.
Since, the elongated link member 224 extends beyond the top edge 302 of the lateral sidewall 210, 212, it facilitates coupling of the hoist chains 118 to the bucket assembly 104 without letting the hoist chains 118 interfere with the lateral sidewalls 210, 212 of the bucket assembly 104. Further, by use of elongated link members 224 to couple the hoist chains 118 with the bucket assembly 104, usage of conventional spreader bar is eliminated. The bucket assembly 104 according to the various embodiments of the present disclosure is light in weight, thereby facilitating an addition to the material handling capacity volume of the bucket assembly 104.
Furthermore, the roller assembly 602 of the elongated link member 224 and the side rail assembly 502 facilitate smooth movement of the elongated link member 224 on the rail 506 during tilting of the bucket assembly 104. The smooth movement of the elongated link member 224 eliminates the friction, the bending force and the interference with the lateral sidewalls 210, 212.
It should be understood that the above description is intended for illustrative purposes only and is not intended to limit the scope of the present disclosure in any manner. Thus, one skilled in the art will appreciate that other aspects of the disclosure may be obtained from a study of the drawings, the disclosure and the appended claims.
Number | Name | Date | Kind |
---|---|---|---|
832894 | Channon | Oct 1906 | A |
916772 | Page | Mar 1909 | A |
1201468 | Iverson | Oct 1916 | A |
1228554 | Hanot | Jun 1917 | A |
1268161 | Sauerman | Jun 1918 | A |
1296800 | Herring | Mar 1919 | A |
1442911 | Steward | Jan 1923 | A |
1448212 | Green | Mar 1923 | A |
2028598 | Gibson | Jan 1936 | A |
2629190 | Berner | Feb 1953 | A |
4689904 | Briscoe | Sep 1987 | A |
5140761 | Coffman | Aug 1992 | A |
5367798 | Hughes | Nov 1994 | A |
8950091 | Cover | Feb 2015 | B2 |
20110110708 | Miotke | May 2011 | A1 |