Note: Descriptions are shown in the official language in which they were submitted.
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BULK STORAGE SILO
Background_of the ~nvention
This invention relates to a portable silo or bulk
storage system for the storage of free-flowing solid
materials, such as powders, grains, pellets or the like.
The system is also suitable for the bulk storage of food
products as well as grain feeds, fertilizers, cement, and
numerous resins available in pellet or flake form. Such
materials are generally referred to herein as "granular"
materials.
The present invention is an improvement over the silo
disclosed in Canadian Patent 1,122,130 issued April 20,
1982, inventor Graham Love, (U.S. Patent 4,306,663 issued
December 22, 1981).
Summar~ of the Invention
More specifical]y, the apparatus described herein
contains improvements over the silo disclosed in such
prior patent in respect of simplification of the design of
the frame and fac:ilitation of the adjustment of tension in
the flexible bands that extend both horizontally and
vertically between the posts and horizontal bars that
constitute the members of a frame in which a flexible bag
is confined.
To this end, the invention consists of a portable silo
for bulk storage of granular material, comprising (a) a
rectangular frame comprising four vertical, metal corner
posts, a plurality of horizontal, metal bars and means for
interconnecting said posts and bars so that upper, lower
and intermediate bars extend between the posts at locations
adjacent the tops and bottoms of the posts and at at least
one level therebetween, said frame defining an open-bottomed
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framework adapted to be free standing on a firm horizontal
floor, said connecting means being capable of ready
assembly and disassembly to permit said posts and bars to
be placed in storage condition; (b) a plurality of
horizontal, flexible bands extending between adjacent
posts, said bands being spaced apart vertically between
the top and bottom horizontal bars; (c) a plurality o-f
vertical, flexible bands extending between the top and
bottom horizontal bars, said vertical bands being spaced
apart horizontally between corner posts; (d) said
horizontal and vertical bands being capable of ready
assembly and disassembly with said posts and bars to permit
the bands to be placed in storage condition; (e) means for
adjusting the tension in said horizontal bands; (f) means
for adjusting the tension in said vertical bands; and (g)
a flexible bag confined by said frame and said bands while
separate therefrom with the bag resting on said floor, said
bag having a filling tube near its top and at least one
discharge tube at a side thereof near its bottom to enable
discharging of the bag while so resting on the floor.
In the preferred embodiment of the invention, each
horizontal band has:
hook means at one end for ready engagement and
disengagement with complementary hook-receiving means
secured to a corner post, and
a nut at its other end for receiving a bolt extending
through an adjacent corner post, said bolt and nut
constituting said means for adjusting the tension in the
horizontal bands.
Also in the preferred embodiment, each vertical band
has a loop at each end through respective ones of which
loops the upper and lower horizontal bars are threaded, and
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said means for adjusting the tension in the vertical
bands comprises vertical adjustment means associated with
said means for interconnecting the posts and bars at least
at one of the upper and lower bars.
Brief Description of the Drawings
The accompanying drawings illustrate one embodiment of
the present invention. In these drawings:-
Figure 1 is a perspective view of a silo and anassociated blower;
Figure 2 is a side or front view of the frame of the
silo of Figure 1, i.e., with the inner bag omitted for
clarity;
Figure 3 is an enlarged, fragmentary view of a portion
of such frame;
Figure 4 is a section on the line IV-IV in Figure 3;
Figure 5 is a section on the line V-V in Figure 2;
Figure 6 is a section on the line VI-VI in Figure 2;
Figure 6A is a section on the line VIa-VIa in Figure 6;
Figure 7 is a section on the line VII-VII in Figure 6;
Figure 8 is a section on the line VIII-VIII in Figure
2; and
Figure 9 is a fragmentary perspective view showing a
modification of a corner portion of the frame.
Description of the Preferred Embodiment
Figure 1 shows a flexible bag 10 of heavy plastic
material, e.g. woven polyolefin material of the type sold
under the Trade Mark Felcolene, this bag being supported
within a frame 11 which defines an open-bottomed peripheral
framework adapted to be free-standing on a firm horizontal
floor. The floor supports the weight of the bag 10 when
full.
In plan view, the frame 11 is square, although other
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rectangular shapes are possib]e. In the example, all four
sides are essentially the same, and hence one description
and one view (Figure 2) thereof will suffice.
There are four, identical, vertical, corner posts 12 of
metal joined together by horizontal, hollow metal bars 13
(at the top), 14 (at the bottom) and 15, 16 and 17 (at
intermediate levels). Conveniently the bars 13-17 can be
identical in construction, to simplify manufacture. A
typical bottom corner connection is shown in Figures 6 and
6A. Welded to the post 12 is a saddle bracket 18 having
extending arms 19 that engage the horizontal bars 14. A
U-shaped strap 20 extends over each of these connections
and a bolt and nut assembly 21 extends through holes in
the strap 20, the arms 19 and the bars 14 to establish a
secured connection.
As shown in Figure 5, the corresponding connection at
the top of the frame involves a similar saddle b~acket 18
with arms 19 joined together beneath the horizontal bar 13
by platforms l9a to which nuts 22a are fixed in which
adjusting screws 22 carrying lock nuts 22b are threaded.
Instead of holes, the arms 19 are formed with slots l9b so
that by adjustment of the screws 22 the vertical position
of the horizontal bars 13 can be modified before they are
firmly fixed in place by tightening of the bolt and nut
assemblies 21. This arrangement enables the spacing
between the top and bottom horizontal bars 13 and 14 to be
adjusted. As an alternative, the vertical adjustment can
be provided at the foot of each post 12 rather than at the
top; or can even be provided both top and bottom.
Similar saddle brackets 18 are welded to the posts 12
at the intermediate locations to connect the intermediate
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horizontal bars 15, 16 and 17. These fixings are basically
the same as those at the top of the frame, although without
the adjustment feature.
Also extending between the corner posts 12 are a series
of horizontal straps 23 of flexible webbing material. As
best seen in Figures 3 and 4, at one end each strap 23 is
stitched into a loop embracing a hooked loop member 24 that
engages a hook-receiving bar 25 welded to a post 12. At
its other end, each strap 23 is stitched to a rigid loop
member 26 having a nut 27 into which there is threaded a
bolt 28 extending through the post 12. Turning of the head
29 of the bo]t 28 will vary the tension in the strap 23.
There are also flexible vertical straps 30 extending
between the top and bottom horizontal bars 13 and 14. As
best seen from Figures 7 and 8, these vertical straps 30
are permanently sewn in loops at each end to embrace the
bars 13 and 14. The frame is assembled by the bars 13 and
14 being threaded through these loops in the straps 30
before the bars are themselves secured at their ends in
the manner already described. As is apparent from Figure
8, the straps 30 are not secured to the intermediate bars
15, 16 and 17, but merely lie against the inside s~rfaces
of such bars. They also pass inside the horizontal straps
23 to which they are not connected.
The simplicity of assembly and disassemly will be
apparent from the foregoing. The post-bar connections
each involves simply slipping a bar end into a bracket 18
and securing with a single bolt and nut assernbly 21. The
vertical flexible bands are merely threaded over the upper
and lower bars and the horizontal bands hooked and screwed
into place.
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The top edge of the bag 10 is connected to the upper
bars 13 by means of cords 39 that may be elastic. These
cords serve merely to support the upper edge of the bag
when empty. When it is full, the weight of the contents
rests on the floor and is not taken by the cords. If
desired the bottom corners of the bag can be connected to
the bottoms of the posts 12 to ensure uniform filling.
In addition, as shown in Figure 9, each lower corner
of the bag 10 can be protected against damage by a piece
44 of tough flexible material including an apron portion
45 located between the bag and any rough edges.
The silo is preferably filled by means of a blower 42
which, as shown in Figure 1, feeds the granular material
to a top loading tube 40 formed in the upper surface of the
bag 10. The tube 40 can be formed with a reinforcing
collar for strength and can be of large diameter to enable
rapid loading. Similarly reinforced discharge tubes 41 are
formed at the bottom of side walls (preferbly three of the
four side walls) of the bag 10. The provision of a
plurality of discharge tubes makes the unloading process
more versatile. The blower 42, now connected to one of the
tubes 41, will normally be used for unloading the granular
material. If two blowers are available, the system permits
simultaneous loading and unloading which is a significant
practical advantage. A ventilator 43 fitted with a fine
screen to permit inflow and outflow of air during loading
and unloading operations can be provided in the top
surface or near the top of one of the side walls of the
bag. When a very fine granular material, such as flour,
is being handled, such ventilator can be connected to an
aspirator tube leading to an appropriate remote Location.
When not in use the tubes 40 and 41 are tied closed.
