Stockpile reclaiming apparatus

The invention consists of a stockpile reclaiming apparatus for discharging bulk material from a bed. The apparatus comprises a bridge which extends over the width of the stockpile, a support frame work, which is mounted from the bridge and a discharging means mounted on the frame work. The discharge means consists of an endless traction means and a series of discharge elements attached to the endless traction means. This endless path is disposed in a plane inclined to the bed of the stockpile whereby an acute angle is formed between this inclination and the plane of the bed.

This invention relates to a stockpile reclaiming apparatus. More 
particularly, this invention relates to a stockpile reclaiming apparatus 
for discharging bulk material from a stockpile. 
As is known, various types of stockpile reclaiming apparatus have been used 
to clear away bulk material stacked in elongate or round stockpiles and to 
transfer the material to a suitable transport means, such as a belt 
conveyor lying externally of and parallel to the stockpile. Generally, it 
is known to clear the stockpiles from the long side, from the head or from 
the end face of the stockpile. The greatest homogenizing effect occurs 
where the bulk material is cleared from the end face of the stockpile. 
Stockpile reclaiming devices which operate at the end face of a stockpile 
are generally displaceable in the direction of the axis of the stockpile 
and are generally comprised of a supporting construction which spans the 
entire width of the stockpile and is mounted on bogies to be movable along 
the stockpile as well as a discharging device mounted on the supporting 
construction. Furthermore, escarpment clearers, such as oscillating rakes, 
pivotable stripper ropes and the like can be included to sweep over the 
stockpile end face and loosen the bulk material so that the material 
trickles into the range of the discharging devices. In some cases, the 
discharging devices are constructed as rotating bucket tubes which extend 
over the entire width of the stockpile, of bucket wheels which are movable 
to-and-fro transversely of the axis of the stockpile and, in particular, 
of scraper elements which rotate parallel to the stockpile end face. 
One known stockpile reclaiming device which is described in DE PS No. 21 55 
355 has scraper equipment which is arranged centrally underneath a 
drivable bridge and which rotates in a plane lying perpendicularly to the 
base of the stockpile and parallel to the stockpile end face. When use of 
this equipment is envisaged at both sides, the scraper equipment must be 
constructed so that the bulk material can move from both sides into the 
range of action of the scrapers. Therefore, no lateral material guides can 
be provided which would prevent issuing of the bulk material on the side 
remote from the stockpile end face. In order to eliminate this factor, it 
is known, for example, from DE PS No. 26 16 807 to let the scraper 
equipment rotate in a plane parallel to the stockpile base and to arrange 
a material guide between both the scraper strands. Nevertheless, a danger 
exists even in this construction that the bulk material remains between 
the material guide and the stockpile bottom and becomes entrained by the 
return run of the scraper equipment lying at the same height as the 
working run and is subsequently dicharged to the opposite side. 
This disadvantageous effect can also arise when the stockpile reclaiming 
apparatus tilts about an axis lying perpendicularly to the axis of the 
stockpile as a consequence of an uneven driving track. 
Further, during the use of the heretofore known reclaiming apparatus, the 
bulk material scrapes on the bottom of the stockpile during the lateral 
discharge. This results in a greater or lesser grain comminution which, in 
many cases, is undesirable. 
Accordingly, it is an object of the invention to provide a stockpile 
reclaiming apparatus wherein bulk material can be discharged from a 
stockpile with optimum grain preservation. 
It is another object of the invention to avoid an undesired material 
conveying by the return run of the discharging device of a reclaiming 
apparatus. 
It is another object of the invention to reduce to a minimum the issuance 
of bulk material out of the range of action of the discharging device. 
Briefly, the invention provides a stockpile reclaiming apparatus for 
discharging bulk material from a stockpile having a predetermined bed. The 
apparatus is comprised of a bridge which extends over the width of the 
stockpile for displacement longitudinally of the stockpile, a support 
frame work mounted on and under the bridge and a discharging means which 
is mounted on the frame work. This discharging means includes an endless 
traction means or organ which is journalled in the frame work in parallel 
to an end face of the stockpile and a plurality of discharge elements 
which are fastened to the endless traction means for movement in an 
endless path parallel to and laterally across the width of the end face of 
the stockpile in order to discharge material at the base of the stockpile. 
In accordance with the invention, the endless path is disposed in a plane 
inclined to the bed of the stockpile. This plane further defines an acute 
angle with the plane of the bed with the apex of the angle directed toward 
the end face of the stockpile. 
Since the discharge elements move through an inclined endless path, the 
return run of the discharging means lies higher than the working run. 
Hence, an undesired discharge of bulk material against the discharge 
elements can be avoided. Further, during discharge, the bulk material no 
longer scrapes on the bottom of the stockpile. Hence, not only is an 
undesired grain comminution avoided but also driving power is conserved 
because of the reduced friction. 
Furthermore, an overall higher discharge performance can be obtained 
through the higher degree of filling of the discharge elements. 
In accordance with the invention, the endless traction means is in the form 
of a link-to-strand chain while each discharge element includes a rear 
wall detachably connected with the chain, an angled bottom and a side 
wall. In the longitudinal run of the chain, the side wall of each 
discharging element forms a second side wall of an adjacent discharging 
element. In addition, where the chain has a plurality of hinge pins, each 
side wall of a discharge element is pivotally mounted on a hinge pin. In 
this way, upon stretching of the chain, each pair of adjacent bottoms 
prevent pivoting of a respective side wall therebetween. 
The frame work may also be pivotally mounted on the bridge about an axis 
parallel to the end face of the stockpile. This allows the apparatus to be 
used between two stockpiles which lie behind each other. In this regard, 
the inclination of the plane of the endless conveyor can be set to 
correspond to the direction of reclaiming.

Referring to FIG. 2, the stockpile reclaiming apparatus includes a bridge 1 
which extends over the width of a stockpile of bulk material. This bridge 
1 is mounted on rail bogies (see FIG. 1) so as to be displaced 
longitudinally of and over the stockpile. 
In addition, the apparatus includes a support frame work 3 which is mounted 
on and under the bridge 1. As indicated in FIG. 2, the supporting frame 
work 3 is pivotable about an axis 2 which is parallel to the end face of 
the stockpile. A suitable chain 4 which can be driven by a drive 5 on the 
bridge is provided for pivoting the frame work 3. Also, a suitable locking 
device 6 is provided to lock the frame work 3 to the bridge 1 for relief 
of the link chain 4 during operation. 
As shown in FIG. 2, the frame work 3 has a discharging means mounted 
thereon. This discharging means includes an endless traction means which 
is journalled in the frame work 3 in parallel to an end face of the 
stockpile and a plurality of discharge elements which are fastened to the 
endless traction means. As shown, the endless traction means is in the 
form of a two-strand chain 11. The chain 11 has a plurality of outer 
runners 10 which are guided between parallel guide tracks 9 disposed on 
two mutually parallel guide carriers 8. As indicated, the pairs of guide 
carriers 8 are arranged on both sides of the supporting frame work 3 in 
parallel to the longitudinal axis thereof. Alternatively, in place of the 
runners 10, skids (not shown) may also be provided. 
Each discharge element includes a rear wall 12 which is detachably 
connected with the chain 11, and angled or bent bottom 13 and a side wall 
17. Each discharge element also carries a roller 14 which is mounted on a 
bottom 13 so as to support the discharge element on a guide rail 15 
connected to the supporting frame work 3. Each side wall 17 is also 
mounted on one of a plurality of hinge pins 16 of the chain 11 so as to be 
pivotable about the axis of the hinge pin 16. Each side wall 17 also 
extends downwardly to such an extent that, in the extended or stretched 
position of the chain 11, the side edges of the bottoms 13 of two adjacent 
discharge elements prevent pivoting of the side wall 17 therebetween. 
Each side wall 17 is also provided with a cutting edge 24 which can be 
plumb, inclined forwardly or rearwardly. 
Referring to FIG. 1, the endless chain 11 loops over a driving tumbler 18 
with an associated drive (not shown) and a tensioning tumbler 19. These 
tumblers 18, 19 are arranged at the end faces of the supporting frame work 
3 as schematically illustrated. 
Referring to FIG. 2, the apparatus is also provided with suitable 
escarpment clearers 7 which are each articulated to a frame work 25 which 
is displaceable on the bridge 1 in the longitudinal direction thereof. 
As shown in FIG. 2, the discharge elements are mounted for movement in an 
endless path parallel to and laterally across the width of the end face of 
the stockpile in order to pick up bulk material directly therefrom. 
Further, the endless path is disposed in a plane 21 which is inclined to 
the bed 20 of the stockpile. Further, this plane 21 of rotation defines an 
acute angle with the plane 20 of the bed with an apex of the angle 
directed toward the end face of the stockpile. 
As shown in FIG. 1, a transport means in the form of a conveyor 26 is 
disposed at the discharge end of the discharge means for sequentially 
receiving bulk material from the end of the discharge elements. 
During operation, the two-strand chain 11 is stretched. In this condition 
of the chain 11, the discharging elements in the working run of the 
conveyor are open for material take-up only upwardly and towards the end 
face 22 of the stockpile. As shown in FIG. 3, as the discharge elements 
deflect at the tumbler 18, wedge-shaped gaps form between the bottoms 13 
of adjacent discharge elements. Further, as a consequence of the inclined 
plane of rotation 21, the bulk material disposed in the discharging 
elements slides out and is transferred to the conveyor 26. In this regard, 
the pivotal side wall 17 of each discharge element remains in bearing 
contact against the side edge of a bottom 13 of the following discharge 
element as viewed in the conveying direction. Further, during travel 
through a returning run of the conveyor, the discharge elements are empty. 
With a stockpile reclaiming apparatus operating only one sidedly, the 
support frame work 3 can be rigidly connected with the bridge 1. Hence, 
the pivot axis 2, link chain 5, drive 5 and locking device 6 are no longer 
needed. Furthermore, the side walls 17 of the discharge element need not 
be pivotally connected with the hinge pins 16. Instead, each side wall 17 
may be rigidly connected with the side edges so as to lie forwardly in the 
conveying direction of the rear walls 12 and bottoms 13. 
It is to be noted that the reclaiming apparatus may be suitable for use in 
removing bulk material which has been stacked in long or round stockpiles.