Bucket wheel with supporting body

A bucket wheel has a conical supporting body constructed as an inner shell rotatably mounted on the bucket wheel axis and a device which co-operates with the supporting body to accommodate the buckets on the outer rim of the bucket wheel. The supporting body is prolonged radially by a prismatic-type outer shell arranged on the supporting body parallel to the device, which has cell-forming dividing walls on its radially outward peripheral region. The prismatic shell, viewed in the radial direction, is shaped from a plurality of approximately trapezoidal steel plates which are welded to one another, making a plurality of bends, to form a polygonal conical envelope.

BACKGROUND OF THE INVENTION 
1. Field of the Invention 
The invention relates to a bucket wheel equipped with a single-wall conical 
supporting body that is constructed as an inner shell and is rotatably 
mounted on the bucket wheel axis. The invention also relates to a device 
cooperating with the supporting body for accommodating the buckets at the 
outer circumference of the bucket wheel. 
2. Description of the Related Art 
German Patent 2,314,241 discloses a non-cellular bucket wheel which has a 
conically configured supporting body that is rotatably mounted on the 
bucket wheel axis and at which is fastened an annular carrier carrying the 
buckets. The supporting body is composed of a single supporting disc 
configured in the form of the envelope of a cone frustum. This 
configuration has the advantage of a very simple structure, with no 
welding work being necessary within a spatial body. Moreover, these bucket 
wheels have the additional advantages that no incompatibilities with 
respect to the shape exist at the connection between wheel and shaft nor 
any sudden changes in rigidity. Additionally, no or hardly any surfaces 
exist which would permit the attachment of dirt. Since it is not possible 
to manufacture the supporting bodies of one piece in dependence on the 
diameter of the bucket wheels, segments must be produced here which lead 
to problems with structural tolerances when later welded together. The 
additional danger exists that the disc composed of a relatively thin metal 
sheet is deformed during welding and must thus be put on the scrap heap. 
However, alternative manufacturing processes such as, for example, deep 
drawing of a metal sheet, are able to overcome these drawbacks. 
German examined published patent application DE-AS 1,073,402 discloses a 
bucket wheel for excavators. The hub supported on the bucket wheel axis by 
two bearing locations has a conical configuration and its tapered end is 
disposed on the side of the bucket wheel facing away from the discharge 
side. Moreover, the discharge chutes are connected to the broadened end of 
the hub and are connected with the tapered end of the hub by supporting 
struts. The ring carrying the buckets is connected with the hub by spokes 
that do not extend radially to the bucket wheel axis; they preferably 
extend tangentially to the tapered end of the hub. This embodiment, which 
is known as a spoke wheel, has the drawback that it requires a relatively 
large amount of welding work in the region of the inner and outer 
circumference of the bucket wheel. Moreover, the danger exists here that 
dirt is able to accumulate relatively quickly in the free spaces between 
the spokes and thus jeopardizes the proper operation of the bucket wheel. 
Although it is easy to see the dirt in view of the open configuration, it 
is relatively expensive to remove it. 
German unexamined published patent application DE-OS 2,609,965 discloses a 
bucket wheel for loading or manipulating bulk materials. The bucket wheel 
is equipped with compartments (cells) for emptying the bulk material, with 
partitions in the housing structure forming the compartments for the 
buckets. At least some of the compartments are open at the edge of the 
housing structure to receive material to be conveyed from the buckets. The 
compartments extend diagonally inwardly from the edge of the housing 
structure in a direction opposite to the direction of rotation of the 
bucket wheel. The compartments are provided with deflecting surfaces that 
slope radially inwardly and at an angle in the direction of rotation of 
the bucket wheel from one side face of the housing structure toward a 
discharge edge of extended length in the second-side face of the housing 
structure. This relatively complicated structural embodiment, also known 
as a cellular wheel, is relatively heavy, on the one hand, and, on the 
other hand, has the drawback that numerous metal sheets and reinforcements 
must be provided at the side walls of the bucket wheel. The bucket wheel 
is composed of a plurality of chambers, with the weld seams being 
absolutely inaccessible. Large areas are formed where dirt is able to 
collect. Here again two bearing locations are required to support the 
complicated structure. Particularly in connection with stockpile clearing 
devices (bucket wheels), the advantage exists that the sloped cell faces 
which extend radially inwardly are amenable to the flow of material and 
thus the inwardly successive material intake location (conveyor belt) is 
protected if heavy chunks come in. 
The prior art bucket wheels in use thus include the so-called non-cellular 
bucket wheels, spoke wheels and cellular bucket wheels, with the robust 
cellular wheels also being usable for difficult applications. 
SUMMARY OF THE INVENTION 
It is an object of the invention to provide a bucket wheel that 
incorporates the advantages of a single-wall non-cellular bucket wheel and 
those of a cellular bucket wheel, with the drawbacks of the double walls 
of a cellular wheel being avoided. 
This is accomplished in that an outer shell in the form of a folded 
structure is disposed on the supporting body as a radially opposite 
extension of the supporting body in the direction of the device and is 
provided with partitions in its radially outward circumferential region 
for the formation of cells. The drawbacks of the cellular wheel (two walls 
and two bearing locations) are avoided in favor of the single-wall 
non-cellular wheel, with the advantages of the cellular wheel (good flow 
of material) remaining in effect. 
Advantageous modifications of the subject matter of the invention are 
defined in the dependent claims. 
Thus, the subject matter of the invention reflects a single-wall cellular 
bucket wheel in which one of the two side walls of the conventional 
cellular wheel configuration can be eliminated and the advantages of the 
non-cellular bucket wheel remain in effect in their entirety. Still no 
cavities exist in which dirt could collect to thus endanger the stability 
of the bucket wheels. Moreover, no sudden changes in rigidity (steps, 
etc.) exist which lead to fatigue damage. In addition, no damage results 
from any incompatibility of shape at the point of connection between wheel 
and shaft.

DESCRIPTION OF THE PREFERRED EMBODIMENT 
FIG. 1 is a side view of the bucket wheel 1 according to the invention. 
Shown is a hub 2 by which it is rotatably fastened on a non-illustrated 
drive shaft. An inner shell 3 in the form of a frustoconical envelope 
extends essentially radially from hub 2. Shaped to it is an outer shell 4 
in the form of a folded structure, with inner shell 3 and outer shell 4 
being connected together by welding. Folded structure 4, which will be 
discussed in greater detail in connection with FIGS. 4 and 5, is composed 
of a plurality of identical, trapezoidal metal sheets 5 which are likewise 
fixed to one another by welding and have the shape of a polygonal cone 
frustum. Partitions 7 that extend perpendicular to the individual metal 
sheets 5 are disposed on the bends 6 of the planar faces of the individual 
metal sheets 5. For reasons of rigidity, so-called sub-dividing sheets 8 
may be provided in addition to partitions 7 to form boxes 9 together with 
partitions 7. For the purpose of protection, wear plates, or sheets, 11 
are welded to the sloped faces 10 of metal sheets 5. The outer 
circumferential surface 12 of bucket wheel 1 also has a polygonal cross 
section. Devices 13 (annular carriers) which have a box-shaped cross 
section are provided in the region of the outer circumferential surface 
12; they likewise have a polygonal cross section and serve to accommodate 
indicated-only buckets 14. 
FIG. 2 is a sectional view seen along line A--A of FIG. 1. Visible are the 
inner shell 3 together with the hub 2, the outer shell 4 as well as cells 
15. Also visible are the boxes 16 of devices 13 and their rear receiving 
elements 17 for buckets 14. Additionally, wear sheets 11 are shown which 
enhance the flow of material and are welded at small distances from one 
another to the sloped faces of metal sheets 5. 
FIG. 3 is a cross-sectional view of the bucket wheel of FIG. 1 as seen 
along line B--B. Visible is the hub 2, the inner shell 3, the outer shell 
4, boxes 16 as well as the front receiving elements 18 for buckets 14. The 
already mentioned wear sheets 11 are welded to the sloped face of outer 
shell 4. 
FIG. 4 is a sectional view of FIG. 1 seen along line C--C. Visible are 
partitions 7 that are perpendicular to bends 6 and the sub-dividing sheets 
8 arranged next to them. The individual cells 15 are each formed by a 
partition 7 and a sub-dividing sheet 8. 
FIG. 5 is a partially developed view of the outer shell 4. Visible are the 
individual trapezoidal metal sheets 5 and bends 6, the raised partition 
walls 7, the sub-dividing sheets 8 as well as the wear sheets 11.