Conveying system for filling multiple storage bins

A conveying system for distributing material into any bin in a horizontal array of storage bins comprises a circular guide positioned over the array of bins (24), a linear guide (22) that rotates along the circular guide, and a conveyor (30) that is supported by the linear guide. By rotating the linear guide and attached conveyor along the circular guide and by shuttling the conveyor linearly, the conveyor has an infinite number of discharge points to fill any one of the underlying array of bins.

FEDERALLY SPONSORED RESEARCH

Not applicable

SEQUENCE LISTING OR PROGRAM

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BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention relates to distribution systems for filling storage bins, specifically to such systems that fill a plurality of closely-spaced bins.

2. Discussion of Prior Art

A significant cost in designing feed mills, grain elevators, and seed conditioning plants, and the like is the distribution system. Facilities such as these typically require many linear meters of conveying equipment. Such equipment can be costly, not only in actual price, but also in terms of maintenance and energy requirements. With the onset of increased purity requirements worldwide, one must also consider cross-contamination issues when choosing methods of distribution. Efficiency and good cleanout, where little or no product remains on the conveyor after it reaches its destination, are two characteristics of conveying systems that are highly desirable in the feed, grain, and seed industries. Current methods of conveying product to bins generally requires a relatively large amount of linear meters of conveyors. Often, the design of a facility's conveying system requires multiple discharge gates, which are sources of cross-contamination and poor cleanout. Filling an array of bins using conventional methods usually requires many linear-feet of conveying equipment, multiple intermediate discharge gates (which are sources of cross-contamination), and a relatively large amount of energy to run the equipment.

Preventing cross-contamination has become a priority in the feed, grain, and seed industries. Cross-contamination issues have become prevalent in recent years due to several factors, such as increased demand for identity preserved traits and the development of genetic engineering to produce genetically modified organisms (GMO). Processors increasingly demand products with characteristics that are best suited for the desired end product. Governments have more strict purity requirements regarding the amount of GMO allowed in Non-GMO products. And consumers desire segregation of GMO from non-GMO products.

Mounting international pressure to trace ingredients to points of origin have also contributed to the need to further prevent cross-contamination, and to segregate ingredients. Segregated storage is a concept that is gaining acceptance in the grain and feed industries, since it can enhance value of stored products and help minimize the potential risks associated with foodborne diseases and bioterrorism. Products can be differentiated by such characteristics as the following: (a) ingredient origin, (b) plant variety, (c) protein level, (d) moisture level, (e) quality, (f) particle size, (g) field origin, (i) growing conditions, (k) foreign matter level, or (l) GMO status, for example. Segregated storage and tracing ingredients to their points of origin have recently become even more important in these industries, not only because of regulations put forward by the European Union, but also due to the first documented case of Bovine Spongiform Encephalopathy, or Mad Cow Disease, in the United States. A diseased dairy cow is believed to have contracted the illness from contaminated feed. Efficient segregated storage, aided with a conveying system that greatly reduces or virtually eliminates the chance of cross-contamination, is a fundamental tool in complying with trace-to-origin regulations, and in reducing risks associated with cross-contamination in general.

Attempts have been made to reduce the amount of linear meters of conveyor required to fill a plurality of bins. Examples of such conveying systems include those disclosed in U.S. Pat. No. 4,330,232 to McClaren (1982), U.S. Pat. No. 3,197,044 to Hozak (1965), U.S. Pat. No. 4,491,216 to Sawby (1985), U.S. 2003/0113194 to Stafford & Elder (2003), and U.S. Pat. No. 3,435,967 to Sackett (1969).

McClaren attempts to fill a plurality of bins arranged in circular arcs about a central pad. Limitations of this arrangement include the following: (1) the use of screw conveyors creates cross-contamination issues, since they are not easily completely cleaned of product; (2) rotation is limited by product receiving area requirements; (3) multiple conveyors are needed to reach outlying bins; and (4) the design requires a relatively large footprint, which may be limiting in many facilities.

Hozak's device is somewhat similar to McClaren's, except it uses belt conveyors. In Hozak's design, the system once again requires a relatively large footprint, and as the height of the bins increase, so does the floor space requirement. This system also requires significant space above the bins. Consequently, very tall roofs, known as head houses, would be required if this system were used in enclosed multi-silo structures.

In Sawby's apparatus, a swiveling conveying system with an extendable auger at the end of a boom that pivots around a mast is limited to filling only one arc of receptacles, it requires a large footprint, and cleanout is relatively difficult.

The conveying system disclosed by Sackett is functionally limited to square or rectangular bins, and it requires multiple conveyors.

Stafford and Elder's device requires a large footprint and is limited to one type of structure.

Other conventional methods of distributing to multiple silos include belt, drag chain, or screw conveyors. These methods incorporate multiple intermediate discharge gates so the conveyor can discharge at multiple points along the conveyor. The problem with all of these conventional conveyors is that the intermediate discharge gates tend to have carryover problems that can cause potential cross-contamination. If the entire product does not fall through the open intermediate discharge gate, the product can be conveyed to an unintended storage bin. Also, intermediate discharge gates on a conventional conveyor tend to seal imperfectly with the conveyor trough, creating further cross contamination potential.

An alternative to using conveying systems, like those described above, is down-spouting. However, down-spouting requires a relatively tall head house, often from about 10 m to 20 m above the bins to be filled. As a result, down-spouted items can reach relatively high speeds, and thus can land harshly within a bin. Such impacts can lower product quality, and so, in many cases, down-spouting is undesirable.

In summary, the following are typical disadvantages of conventional conveying or spouting systems to fill a cluster of bins:(a) many linear meters of conveyor are needed, which increases cross-contamination risk and adds to energy and maintenance costs;(b) multiple discharge gates are often necessary, which increases risk of cross-contamination;(c) multiple motors are usually needed, which adds to energy and maintenance costs; and(d) a large footprint is often required.

Objects and Advantages

Accordingly, several objects and advantages of the present invention are:(a) to provide an improved conveying system that can fill a plurality of closely-spaced storage bins with minimal linear meters of conveyors, thus lowering associated energy requirements and maintenance costs;(b) to provide a conveying system that eliminates a need for multiple discharge openings and intermediate discharge gates, thus reducing risks associated with cross-contamination; and(c) to provide a conveying system in which product quality is preserved.

Further objects and advantages are to provide a conveying system that is efficient in terms of cost, clean-out, space requirements, energy requirements, and maintenance. The conveying system can also be automated, with electrical location sensors that can position the discharge end(s) of the conveyor at an infinite number of discharge locations, to expand its efficiencies. Still further objects and advantages will become apparent from a consideration of the ensuing description and drawings.

SUMMARY

In accordance with the present invention, a conveying system for feeding a plurality of closely-spaced horizontally arrayed storage receptacles with or without shared walls from above comprises a conveyor that is supported by and shuttles along a linear track. The linear track is supported by and rotates along a curvilinear track. The conveyor discharges product into a selected one of a plurality of underlying storage receptacles. The conveying system provides an infinite number of discharge points.

A preferred embodiment of a rotating multiple-track horizontal conveying system of the present invention is shown in an isometric view inFIG. 1.FIG. 1shows the embodiment at rest, with an underlying structure comprising multiple bins that are horizontally arrayed. Only top portions of the bin structure is shown, for reference, since virtually any type of well-known multiple bin array configuration can be used.FIG. 2shows the conveying system in a new position rotated about 45 degrees from its position inFIG. 1and retracted to a selected bin20that is ready to be filled. As seen inFIGS. 1 and 2, the conveying system includes two parallel linear tracks22and one arcuate track24. In general, the number of concentric arcuate tracks can range from one to several, depending on the type of track used, the weight of items to be conveyed, and the distance that items will be conveyed, as will be discussed elsewhere. Linear tracks22preferably support a horizontal belt conveyor30, but standard screw or drag types of conveyors can be used. In the example inFIGS. 1 and 2, powered trucks (trolleys)34and36support linear tracks22above arcuate track24. In general, however, linear tracks can be supported above or suspended below the arcuate track or tracks.

Linear tracks22and arcuate track24work in conjunction with each other to position discharge ends44over any desired bin within the cluster of bins. Means of powering movement along the tracks are not shown, but I presently prefer one motor for linear movement and another for rotational movement. However, use of power chains and drive motor(s), a hydraulic system, manual rotation and shuttling, or a single motor to move both linearly and rotationally can be alternatively employed. The rotating horizontal conveying system can also be automated (not shown), for example, with electrical location sensors, and/or bin level indicators that indicate when a bin is full. In the example, tracks22and24are standard monorail I-beam tracks, but any suitable standard track configuration can alternatively be used. For example, flat bar, I-beam, C-beam, double-channel, enclosed tubular, bolted angles, and T-track are suitable for the conveying system, based in part on the weight of items to be conveyed and the distance that items will be conveyed.

The diameter of arcuate tack24as shown inFIGS. 1 and 2is about 6.3 m, much smaller than the approximate collective 27.4-m diameter of the bin cluster in the example. Consequently, an assembly for preventing conveyor30and linear track22from derailing due to severely unbalanced loads can be incorporated. A fri-cam truck/trolley assembly, such as powered trolleys34and36which act as rotatable means and are shown more clearly inFIG. 3B, is usually sufficient to prevent such a calamity. Other trolley assemblies or methods can be engineered to withstand the weight of the equipment and the product being conveyed, while preventing conveyor30from tipping off of the track system, by those skilled in the art. For example, conveyor30and/or linear tracks22can include a cantilever device. Generally, any appropriate radius for arcuate track24, any suitable trolley assembly, any well-known cantilever system (not shown), and/or multiple concentric arcuate tracks can be used in this conveying system.

In the example inFIGS. 1 and 2, linear tracks22are about the same length as conveyor30, and they are significantly longer than the diameter of arcuate track24. Alternatively, linear tracks22can be significantly shorter than conveyor30, such that discharge ends44of conveyor30extend beyond the end of linear tracks22. In such instances, means to counterbalance the weight of the product being conveyed and the weight of the equipment is employed (not shown). For example, load bar37of second powered trucks36would be attached directly to conveyor30so that conveyor30would shuttle directly along linear tracks22, which would be fixed. Linear tracks22would only rotate about arcuate track24via first powered truck34, rather than also translating laterally on second powered trucks36. This type of situation will be discussed further elsewhere.

Catwalk46is attached to conveyor30, for maintenance and service access, and so it also moves with the conveyor, as seen inFIGS. 1-3. Catwalk46is not required when conveyor30is easily and safely accessible.

Conveyor30can be of the standard screw, belt, or drag-chain types. However, belt conveyors provide more complete product cleanout compared to other types of conveyors. Consequently, belt-type conveyors are usually preferable, especially if reducing cross-contamination is a priority. In the example inFIGS. 1 and 2, the horizontal length of conveyor30is slightly less than the collective 13.25-m (about 43.5-ft) radius of the bin cluster. Conveyor30is reversible, or bi-directional, in the example, so it has two discharge ends44. Only one discharge end44can be used at a time, since conveyor30travels in one direction at a time.

Conveyor30can receive product at virtually any point along its length, and it is usually fed from a fixed point. Typically, a fixed vertical conveying system (not shown) transfers product from a receiving area (not shown) to conveyor30. Conveyor30can be fed by a variety of well-known existing vertical-conveying methods, including, but not limited to, the following: (a) a bucket elevator that rises through and is spouted to about the center axis of the arcuate track or tracks, where it discharges onto conveyor30; (b) a bucket elevator that rises through an offset location within the cluster of bins and is spouted to conveyor30; (c) a bucket elevator that is positioned outside the diameter of the bin cluster and discharges onto a stationary horizontal conveyor, which transfers product to discharge onto conveyor30; or (d) a pneumatic conveying system, which uses air pressure, that discharges onto conveyor30.

In the example inFIGS. 1 and 2, arcuate track24is supported directly by portions of the underlying multiple bin array, namely load-bearing columns48with caps50. Struts can be added where required (not shown). Other track support means are possible. For example, the tracks can be suspended from above, as will be discussed elsewhere, or supported by other suitable means, such as structural columns, with or without struts, that are independent of the underlying bin array.

InFIG. 3A, a first set of powered trucks34rotates along arcuate track24. A load bar37of a second set of powered trucks34is oriented perpendicular to a load bar35of first powered truck34, and attaches to first powered track34. Linear tracks22with attached conveyor30move along second powered trucks36. In a close-up view ofFIG. 3B(taken fromFIG. 3A), wheels48, rods40, and load bars35and37can be seem more clearly. In thin example, each truck34and36has three wheels48with connecting wheel rods50. Although a tri-wheel trolley assembly is shown, other known suitable means for allowing movement along the tracks can be used, such as dual-cam assemblies, other wheel configurations, bearings, etc. Powered trucks are used in this preferred embodiment, but other well-known types of trolley systems or movement systems can be used.

Thus, only one horizontal conveyor, with infinite discharge points and a minimal amount of linear meters, is needed to fill a plurality of bins; no intermediate discharge gates are required; and overhead space requirements are minimal, usually requiring no more than about 1–2 m (about 3–6 feet).

In operation, the rotating horizontal conveying system is seen in a resting position inFIG. 1, before it is moved to feed the desired bin20inFIG. 2. InFIG. 2, conveyor30ofFIG. 1is rotated 90 degrees along arcuate track24, and conveyor30is extended along linear track22until discharge end44is positioned above bin20. Conveyor30is now ready to receive product from a feeding conveyor system (not shown). The feeding conveyor system can be of any number of suitable configurations, such as those discussed previously.

When using a reversible conveyor, such as the one shown inFIG. 1and discussed previously, conveyor30and attached catwalk46need rotate only 180 degrees or less to be able to access any given silo within a cluster of silos. If a non-reversible, or uni-directional, conveyor is used, then the conveyor-catwalk assembly will need to rotate about 360 degrees.

In an alternative embodiment as shown inFIG. 4, concentric arcuate tracks26and28can be added, if additional support or balancing of linear track22or conveyor30is needed. Linear tracks22extend about the full diameter of outermost concentric arcuate track28. Powered trucks34and36of this system are modified so that linear tracks22are affixed to load bar35of first powered truck34. Load bar37of second powered truck36attaches to conveyor30(or conveyor30with catwalk46, not shown) so that conveyor30(and attached catwalk46, when required) shuttles along linear tracks22. As a result, in this embodiment, linear tracks22only rotate along arcuate tracks24,26, and28rather than also translating along second powered trucks36as shown inFIGS. 1 and 2(previously discussed). Trucks34and36need not be powered, as in this example. Other well-known trolley or wheel assemblies may be used to achieve rotation and linear movement.

As also shown inFIG. 4, more than one horizontal conveyor and linear track system can be incorporated on the same arcuate track system. A second conveyor52and its associated embodiments, such as linear track system, catwalk, or both, is arranged in parallel to conveyor30. Thus, more than one bin can be filled simultaneously.

FIG.5: Suspended from Roof

In another alternative embodiment, as shown inFIG. 5, arcuate track24can be suspended from above, such as from roof rafters (not shown), with linear tracks22suspended below arcuate track24. The arrangement of first powered trucks34differs slightly from previously described embodiments in that load bars35are inverted, to support second trucks36, linear tracks22, and conveyor30below arcuate track24. Such trolley/truck systems can vary according to methods that are well-known to those skilled in the art, and so the embodiment is not limited to the example shown here.

A suspended embodiment, like the one shown inFIG. 5, can exist alone or co-exist in the same structure with the preferred embodiment shown inFIGS. 1 and 2(not shown). This alternative embodiment can also be used alone or at the same time as the preferred embodiment previously discussed, to fill more than one bin simultaneously. In such a suspended system, a telescoping spout(s) (not shown) with adequate length to reach underlying bins may be required at discharge end(s)44of conveyor30. The suspended system can be fed by a feeding system that is the same or different from that feeding the first system.

Conclusion, Ramifications, And Scope

The present conveying system can be used to fill a plurality of closely-spaced bins from above with maximum efficiency since it provides a means for infinite discharge locations, using only one horizontal conveyor. The need for intermediate discharge gates, which significantly increase risks of cross-contamination, is eliminated. Furthermore, the improved rotating horizontal conveying system has the additional advantages in that it is more economical to build, install, operate, and maintain than conventional conveyor or spouting distribution systems.

Although the description above contains many specificities, these should not be construed as limiting the scope of the invention, but as merely providing illustrations of some of the presently preferred embodiments of this invention. Other embodiments are possible. For example, the conveyor can be replaced by other known types of conveyor, such as drag or chain types; and/or other known types of track systems can be used, such as flat bar, I-beam, C-beam, double-channel, enclosed tubular, bolted angles, or T-track; and/or other known types of truck or trolley assemblies can be used. The system can be used to fill a plurality of bins that are of other polygonal shapes, such as square, rectangular, or octagonal. The system can be used to fill a plurality of closely spaced round bins. The arc of the arcuate track can be less than 360 degrees. More than one conveyor and linear track assembly can be used simultaneously on one arcuate track system; and/or more than one arcuate/linear track/conveyor assembly can co-exist to feed multiple bins simultaneously. The conveyor can have telescoping spouts at its discharge ends; it can be non-reversing, having only one discharge end and one tail end; it can incline or decline from horizontal; the system can be automated; and/or the conveyor can be enclosed, with or without telescoping spouts at discharge and/or inlet points; etc. Thus the scope of the invention should be determined by the appended claims and their legal equivalents, rather than by the examples given.