Dragline buckets

Abstract

A dragline bucket comprising: a floor having a ground engaging leading edge, a rear wall extending upward from said floor and spaced rearward from said leading edge, and two spaced apart side walls extending upward from said floor and forward from said rear wall, the upper edges of said rear wall and said side walls defining an open top and the height from said floor of at least a portion of said side walls forward of said rear wall being substantially less than the height of said side walls adjacent said rear wall.

1 - 14 . (canceled) 
     
     
         15 . A dragline bucket comprising:
 a floor having a ground engaging leading edge, a rear wall extending upward from said floor and spaced from said leading edge, and two spaced apart side walls extending upward from said floor and forward from said rear wall towards said leading edge, the upper edges of said rear wall and said side walls defining an open top and the height of said rear wall and said side walls from said floor decreasing away from about the centre of said rear wall to at least respective predetermined points along said side walls.   
     
     
         16 . A dragline bucket according to  claim 15  wherein said predetermined points are located about midway between said rear wall and said leading edge. 
     
     
         17 . A dragline bucket comprising:
 a floor having a ground engaging leading edge, a rear wall extending upward from said floor and spaced from said leading edge, and two spaced apart side walls extending upward from said floor and forward from said rear wall towards said leading edge, the upper edges of said rear wall and said side walls defining an open top and at least a portion of the upper edge of each said side wall lying in a plane containing a line extending from about the centre of the upper edge of said rear wall to about said leading edge.   
     
     
         18 . A dragline bucket according to  claim 17  wherein the portion of the upper edge of each side wall lying in said plane extends from said rear wall to a predetermined point between said rear wall and said leading edge. 
     
     
         19 . A dragline bucket according to  claim 18  wherein said predetermined point is a point where the height of said side walls is about half the height of said rear wall. 
     
     
         20 . A dragline bucket according to  claim 15  wherein said side walls and said rear wall terminate in a top rail running along their respective upper edges or formed by their upper edges. 
     
     
         21 . A dragline bucket according to  claim 15  including a lifting arch operatively connected to said floor and/or said side walls forward of said rear wall, said leading edge and said lifting arch together defining at least in part a mouth through which spoil may enter. 
     
     
         22 . A dragline bucket according to  claim 21  wherein said side walls and said rear wall terminate in a top rail extending from the lifting arch on one side of the mouth to the lifting arch on the other side of the mouth. 
     
     
         23 . A dragline bucket according- to  claim 21  including generally horizontal top rails spaced above the upper edges of said side walls respectively along a substantial portion thereof. 
     
     
         24 . A dragline bucket according to  claim 21 , wherein the side walls curve upwards from said predetermined point towards said lifting arch. 
     
     
         25 . A dragline bucket according to  claim 17  wherein said side walls and said rear wall terminate in a top rail running along their respective upper edges or formed by their upper edges. 
     
     
         26 . A drag line bucket according to  claim 17  including a lifting arch operatively connected to said floor and/or said side walls forward of said rear wall, said leading edge and said lifting arch together defining at least in part a mouth through which spoil may enter. 
     
     
         27 . A dragline bucket according to  claim 26  wherein said side walls and said rear wall terminate in a top rail extending from the lifting arch on one side of the mouth to the lifting arch on the other side of the mouth. 
     
     
         28 . A dragline bucket according to  claim 26  including generally horizontal top rails spaced above the upper edges of said side walls respectively along a substantial portion thereof. 
     
     
         29 . A dragline bucket according to  claim 26 , wherein the side walls curve upwards from said predetermined point towards said lifting arch. 
     
     
         30 . A dragline bucket comprising:
 a floor having a ground engaging leading edge;   a rear wall spaced from said leading edge and extending upwards from said floor and curving forward from its centre on both sides thereof to meet two spaced apart side walls also extending upward from said floor and forward from said rear wall, the upper edges of said rear wall and said side walls defining an open top.   
     
     
         31 . A dragline bucket according to  claim 30  wherein said side walls and said rear wall terminate in a top rail running along their respective upper edges or formed by their upper edges. 
     
     
         32 . A dragline bucket according to  claim 30  including a lifting arch operatively connected to said floor and/or said side walls forward of said rear wall, said leading edge and said lifting arch together defining at least in part a mouth through which spoil may enter. 
     
     
         33 . A dragline bucket according to  claim 32  wherein said side walls and said rear wall terminate in a top rail extending from the lifting arch on one side of the mouth to the lifting arch on the other side of the mouth. 
     
     
         34 . A dragline bucket according to  claim 32  including generally horizontal top rails spaced above the upper edges of said side walls respectively along a substantial portion thereof. 
     
     
         35 . A dragline bucket according to  claim 32 , wherein the side walls curve upwards from said predetermined point towards said lifting arch. 
     
     
         36 . A method of operating a dragline, including:
 providing a dragline having a dragline bucket as claimed in  claim 15 , including:   dragging the bucket through spoil in a forward direction to substantially fill a front portion of the bucket and then lifting the ground engaging leading edge while continuing dragging in the forward direction to tilt the front of the bucket upwards whereby spoil accumulated adjacent the mouth of the bucket moves towards the rear wall of the bucket;   tilting the bucket to a predetermined carry angle;   lifting the bucket to a desired height;   carrying the bucket to a dump site; and   dumping the spoil at the dump site.