This application takes priority from U.S. Provisional Patent Application 61/584,484 filed on January 9, 2012, which is incorporated herein by reference.

Background

What is presented is a system and method for the removal of oversized material from a material stream. Material sorting systems are found in shredding mills, scrap metal plants, and the like, and they typically have sizing grates intended to limit the size of material passing through to the end of the system, ensuring a relatively uniform material size exiting the sorting system. However, these grates will only screen materials in two dimensions and elongated pieces of oversized material, often called "pokers," sometimes pass through. While these pokers represent a tiny percent of the weight passing through these systems, they cause a majority of the material handing problems because these pokers easily jam in transfer chutes, poke holes in belts of conveyors (if any exist), and are hazardous to the operating and handpicking personnel. Thus, it would be desirable to have a system and method that removes oversized material within a material stream.

Summary

What is a presented is an oversized material removal system for the removal of oversized materials from a material stream. The oversized material removal system comprises a first transfer system, for the transportation of a material stream, and a pulley separator, comprising a rotatable outer shell. Furthermore, the outer shell has a tubular width and a circular cross-section. The pulley separator is also located at a discharge end of the first transfer system and creates a gap that is at least the length of the oversized materials.

The oversized material removal system could also comprise a storage device or a second transfer system that is further downstream from the pulley separator. The outer shell of the pulley separator could be rubber coated or have a magnet located within it. Moreover, if there is one, the magnet located within the outer shell could be upwardly oriented. The outer shell of the pulley separator could also have a width that is at least the same as the width of the first transfer system.

The first transfer system of the oversized material removal system could be a conveyor that comprises a drum, which rotates around a central axis, and a belt, which covers the drum. Furthermore, the drum and outer shell both rotate in the same general direction. The outer shell could also generally rotate at a faster rate of speed than the drum. The gap of the oversized material removal system could also be between 12 inches to 24 inches.

Another embodiment of the oversized material removal system for the removal of oversized materials from a material stream comprises a grate used for pre-sorting the material stream, an aligning device used for pre-positioning the oversized materials within the material stream, a conveyor used for the transportation of the material stream, a pulley separator, and a storage device located downstream of the pulley separator. The aforementioned conveyor comprises a drum, that is rotatable around a central axis, and a belt, which covers the drum.

The aforementioned pulley separator of this embodiment comprises a rotatable outer shell and an upwardly oriented permanent magnet, which is located within the outer shell. Furthermore, the outer shell is rubber coated and has a tubular width and a circular cross-section. The pulley separator is located at a discharge end of the conveyor in such a way that this location creates a gap, which is at least the length of the oversized materials. The drum and outer shell both rotate in the same general direction and the outer shell generally rotates at a faster rate than the drum.

A method of removal of oversized materials from a material stream comprises the first step of conveying a material stream, that includes oversized materials, along a first transfer system to a discharge end of the first transfer system and the second step of conveying the oversized material, from the discharge end of the first transfer system, over a pulley separator, which is located downstream from the first transfer system across a gap between the first transfer system and the pulley separator that is at least the length of the oversized materials.

The method of removal of oversized materials could also comprise and additional step of conveying the oversized material, from over the pulley separator, to a second transfer system or a storage device that is located downstream from the pulley separator.

Brief Description of Drawings

For a more complete understanding and appreciation of this invention, and its many advantages, reference will be made to the following detailed description taken in conjunction with the accompanying drawings.

Fig. 1 shows a side view of the prior art components of a material transfer and sorting system;

Fig. 2 shows a perspective view of a single elongated piece of oversized material;

Fig. 3 shows a front view of a single elongated piece of oversized material;

Fig. 4 shows a side view of a single elongated piece of oversized material; Fig. 5 shows a side view of a prior art static oversized material removal system;

Fig. 6 shows a side view of a prior art driven oversized material removal system;

Fig. 7 shows a perspective view of a material stream comprising the first embodiment of the oversized material removal system;

Fig. 8 shows a side view of the first embodiment of the oversized material removal system;

Fig. 9 shows a side view of a second embodiment of the oversized material removal system where the pulley separator has a rubber coat around the drum;

Fig. 10 shows a side view of a third embodiment of the oversized removal system;

Fig. 11 shows a side view of a fourth embodiment of the oversized removal system;

Fig. 12 shows a side view of a fifth embodiment of the oversized removal system;

Fig. 13 shows a flow chart of a method of removing oversized from a material stream;

Fig. 14 shows a flow chart of a second embodiment of the method of removing oversized from a material stream.

Detailed Description

Referring to the drawings, some of the reference numerals are used to designate the same or corresponding parts through several of the embodiments and figures shown and described. Corresponding parts are denoted in different embodiments with the addition of lowercase letters. Variations of corresponding parts in form or function that are depicted in the figures are described. It will be understood that variations in the embodiments can generally be interchanged without deviating from the invention. As shown in Fig. 1, material transfer and sorting systems found in shredding mills, scrap metal plants, and the like, process material 10 in a material stream 12 by first breaking up the material 10 into manageable chunks to free up different material types, so that the material 10 can be sorted and graded by the downstream processes. This incoming material 10 is typically shredded, ground up, crushed, and/ or torn at a breaking site 14 before the material 10 is ejected onto a first transfer system 16, and then carried downstream for processing. The breaking site 14 may be a crusher, a shredder, or other device or combination of devices. The first transfer system 16 may be a conveyor, an angled chute, or any other appropriate system or combination of systems.

At least one sizing grate 18 is installed downstream of the breaking site 14 to presort the material stream 12 and further limit the size of the material 10 within the material stream 12 that is moving along the first transfer system 16. The grate 18 helps to ensure that there is a relatively uniform material stream 12 transporting along the first transfer system 16. The grate 18 typically has, but is no way limited to, a plurality of openings that are 5 inches by 8 inches in the height and width dimensions, respectively. However, as can be seen in the prior art shown in Figs. 2 through 4, a major limitation of these grates is that they will only screen materials in the two dimensions of height 20 and width 22, but not length 24. It is commonplace for elongated pieces of oversized material 26 to pass through the grate 18 and continue transporting downstream on the first transfer system 16. These elongated pieces of oversized material 26, sometimes called "pokers," are long axis bars, short in height 20 and width 22, having lengths 24 beginning from around two feet to much longer. While oversized material 26 represents a tiny percent of the weight passing along the first transfer system 16, oversized material 26 is a major cause of downstream disruptions. Oversized material 26 removal is even more necessary when the material stream 12 of the material sorting systems takes at least one sharp turn during transfer, potentially causing pieces of oversized material 26 to get jammed and obstruct the flow of the material stream 12 behind the oversized material 26. This obstruction can severely damage parts of the material sorting system's first transfer system 16 or other components. This obstruction can also cause lost production time and waste workforce effort to clear the oversized material 26 from the obstructed material stream 12.

Solutions to the problems caused by these escaping oversized material 26 pieces have been attempted in the past. As shown in Fig. 5, prior art static oversized material removal systems 28a are non-driven, not active, and leave much to be desired. These static oversized material removal systems 28a essentially rely upon the oversized material 26a, traveling in the material stream 12a and along a first transfer system 16a, to simply lodge themselves on a capturing platform 30a, typically a sheet or shelf, that is situated a short distance beyond the natural trajectory of the material stream 12a while falling off the discharge end of the first transfer system 16a. Using this system, very few pieces of oversized material 26a, except the exceptionally elongated ones, actually get removed from the material stream 12a because most pieces of oversized material 26a end up falling back in with the rest of the material stream 12a when they miss the capturing platform 30a.

As shown in Fig. 6, another prior art solution that has been created is the driven oversized material removal system 28b. This oversized material removal system 28b relies upon friction and/or the oversized material's 26b own weight to allow capture, making the entire design of the oversized material removal system 28b unreliable. These driven oversized material removal systems 28b are simply a small diameter rubber coated roller 32b located above the discharge end of the first transfer system 16b. The roller 32b functions by imparting additional momentum to the material 10b in the material stream 12b with the intention of providing more momentum to the oversized materials 26b. However, this system is unreliable as it is possible that some oversized material 26b may miss the roller 32b entirely or some smaller material 10b may be unduly affected by the roller 32b and ejected to the capturing platform 30b. This type of oversized material removal system 28b is particularly ineffective on pieces of oversized material 26b that are shorter in size or have abnormal weight distributions, causing this system to be even less reliable in general.

To get around the substantial inefficiencies found in the prior art solutions above, a oversized material removal system 28c, that will be discussed in greater detail below, has been created. As shown in Figs. 7 and 8, a first embodiment of this oversized material removal system 28c, comprises a first transfer system 16c used for the transportation of the material stream 12c to the discharge end of the first transfer system 16c. The first transfer system 16c in this embodiment is a shown as a conveyor that comprises at least one rotatable drum 34c, which rotates around a central axis 36c, and a belt 38c that covers the rotatable drum 34c. It is also possible for the first transfer system 16c to comprise an aligning device (not shown) that helps position the material stream 12c so oversized material 26c within the material stream 12c becomes aligned lengthwise while being transported on the first transfer system 16c.

A pulley separator 40c is located downstream and in line with the discharge end of the first transfer system 16c, just beyond a gap 42c that is approximately the length of oversized material 26c to be removed from the material stream 12c. The length of this gap 42c typically ranges from around 12 inches to 24 inches, which should be a length that is at least as small as the shortest pieces of the oversized material 26c. It will be understood that the length of this gap 42c could be selected for the particular application as long as it is long enough to only allow oversized materials 26c from the material stream 12c to pass over the gap 42c.

The pulley separator 40c comprises a rotatable outer shell 44c that is rotated by a drive mechanism (not shown) and has a tubular width 46c and circular cross-section 48c. The tubular width 46c of the outer shell 44c is typically at least the same width of the first transfer system 16c. The tubular width 46c of the outer shell 44c is in line with the width of the first transfer system 16c to facilitate removal of oversized material 26c at any point along the width of the first transfer system 16c. It will be understood that while a tubular width 46c of the outer shell 44c that is shorter than the width of the first transfer system 16c can work, such an arrangement will be unable to service the removal of oversized materials 26c from the entire width of the first transfer system 16c. The cross-section 48c of the pulley separator 40c could have a non-circular shape, such as, but not limited to, an octagon, square, oval, etc. shape. Implementing various non-circular shaped cross-sections 48c of the outer shell 44c may be effective in facilitating the gripping of certain oversized material 26c expected to have diversely shaped lengths 46c created by kinks, bends, and knots.

A magnet 50c is located within the outer shell 44c. The magnetic field of the magnet 50c attracts oversized materials 26c that have ferrous or otherwise magnetic properties against the rotating outer shell 26c of the pulley separator 40c and be pulled forward by the rotation of the outer shell 44c. The magnetic field of the magnet 50c helps to prevent oversized material 26c from falling backward into the gap 42c. Thus, when the material stream 12c reaches the gap 42c, oversized material 26c will pass over the gap 42c due to its length as well as be affected by the magnetic field generated by the magnet 50c located within the outer shell 44c, all other material 10c will likely fall into the gap 42c. The magnet 50c is typically upwardly oriented because oversized material 26c passes over the top of the pulley separator 40c. It will be understood that any orientation of the magnet 50c may work, so long as oversized material 26c can pass over the pulley separator 40c. The magnet 50c is typically a permanent magnet. However, it will also be understood that other varieties of magnets may work, such as electro-magnets, so long as the magnetic field of the magnet 50c is strong enough to help prevent oversized material 26c from falling back into the gap 42c after the oversized material 26c comes into contact with the pulley separator 40c.

The outer shell 44c of the pulley separator 40c rotates in the same direction as the movement of the material stream 12c on the first transfer system 16c. Typically, the outer shell 44c rotates at a faster rate of speed than the material stream 12c is moved across the first transfer system 16c, so as to facilitate the quick removal of the oversized material 26c. Generally the outer shell 44c rotates 25% to 50% faster than the material stream 12c moves along the first transfer system 16c. It will be understood that rotating the outer shell 44c at any speed to facilitate the removal of the oversized material 26c will work. It is also possible to incorporate a timing device (not shown) with the outer shell 44c so as to vary the rotational speed of the outer shell 44c at different set time increments, further helping to facilitate removal of the oversized material 26c.

Further downstream, beyond the pulley separator 40c, lies a storage device 52c that is typically a shelf, sheet, or collection bin, for collecting each piece of oversized material 26c that has passed over the pulley separator 40c. It will be understood that any type of storage device able to collect each piece of oversized material 26c passed over the pulley separator 40c will work. Moreover, there is a short distance between the downstream side of the pulley separator 40c and the storage device 52c, creating a much smaller second gap 54c that only oversized material 26c can easily slide over. Any material 10c from the material stream 12c that mistakenly goes over the pulley separator 40c will drop off on the downstream side of the pulley separator 40c into the second gap 54c, sending this material 10c back with the rest of the material stream 12c.

In a second embodiment of oversized material removal system 28d shown in Fig. 9, the pulley separator 40d comprises a rotatable outer shell 44d that is rotated by a drive mechanism (not shown) and has a tubular width 46d and circular cross-section 48d. The outer shell 44d has a rubber coat 56d covering the outer shell 44d. The rubber coat 56d uses the friction of the rubber coat 56d against the oversized material 26d to pull the oversized material 26d forward and across the top of the pulley separator 40d with the rotation of the outer shell 44d. The rubber coat 56d can be particularly effective in situations where the material stream 12d comprises oversized material 26d having no ferrous properties. Thus, when the material stream lOd reaches the gap 42d, oversized material 26d will pass over the gap 42d due to its length and be affected by the frictional grip of the rubber coat 56d covering the outer shell 44d, all other material lOd should fall into the gap 42d. Typically the rubber coat 56d covers the entire outer shell 44d. It will be understood that the rubber coat 56d could cover any portion of the outer shell 44d so long as oversized material 26d can be effectively gripped and pulled across the top of the pulley separator 40d by the rotation of the outer shell 44d.

As shown in Fig. 10, the third embodiment of the oversize material removal system includes a first transfer system 16e that is a chute used for the transportation of the material stream 12e. The first transfer system 16e relies on gravity to move the material stream 12e forward, until the material stream 12e reaches the discharge end of the first transfer system 16e. Typically the chute 12e is designed to have a channel shape or side walls so that a majority of the material stream 12e remains on the first transfer system 16e and does not spill over the sides of the first transfer system 16e as the material stream 12e transports downstream toward the discharge end.

A pulley separator 40e is located downstream from the discharge end of the first transfer system 16e, just beyond a gap 42e that is approximately the length of oversized material 26e to be removed from the material stream 12e. The length of this gap is typically around 12 inches to 24 inches, which is at least as small as the shortest pieces of the oversized material 26e. It will be understood that any gap 42e long enough to enable only oversized materials 26e from the material stream 12e over the gap 42e will work.

The pulley separator 40e comprises a rotatable drum 34e that is rotated by a drive mechanism (not shown) and has a tubular width and circular cross-section (not shown). The tubular width of the outer shell 44e is typically at least the same width of the first transfer system 16f. Having the tubular width of the outer shell 44e the same as the width of the first transfer system 16e facilitates removal of oversized material 26e at any point along the width of the first transfer system 16e. It will be understood that any tubular width of the outer shell 44e, making removal of the oversized material 26e at any point along the width of the first transfer system 16e possible, will work.

The outer shell 44e of the pulley separator 40e generally rotates in the same direction as the movement of the material stream 12e being transported by the first transfer system 16e. Typically, the outer shell 44e of the pulley separator 44e rotates at a faster rate of speed than the movement of the material stream 12e along the first transfer system 16e so as to further facilitate the quick removal of the oversized material 26e. Generally the outer shell 44e rotates 25% to 50% faster than the movement of the material stream 12e. It will be understood that rotating the outer shell 44e at any speed facilitating the removal of the oversized material 26e will work. It is also possible to incorporate a timing device with the outer shell 44e so as to vary the rotational speed of the outer shell 44e at different varying speeds or at set time increments, further helping to facilitate the removal of the oversized material 26e.

Further downstream, beyond the pulley separator 40e, lies a storage device 52e, that is typically a shelf, sheet, or collection bin, for collecting oversized material 26e that has passed over the pulley separator 40e and is ready for collection. It will be understood that any kind of device able to collect oversized material 26e, that has passed over the pulley separator 40e and is ready for collection, will work. Moreover, there is a short distance between the downstream side of the pulley separator 40e and the storage device 52e, creating a much smaller second gap 54e that only oversized material 26e easily slides over. Any material lOe from the material stream 12e mistakenly goes over the pulley separator 40e will drop off on the downstream side of the pulley separator 40e into the second gap 54e, sending it back into the material stream 12e.

As shown in Fig. 11, the fourth embodiment of the oversized material removal system 28f comprises a second transfer system 58f, which is an extraction conveyor, downstream beyond the pulley separator 40f is. The second transfer system 58f is used for the transportation of the oversized material 26f extracted from the material stream 12f to another location even further downstream of the oversized material removal system 28f. The second transfer system 58f, in this embodiment, comprises a rotatable second drum 60f, which rotates around a second central axis 62f, and a second belt 64f that covers the second drum 60f.

In a fifth embodiment of the oversized material removal system 28g, as shown in Fig. 12, both the first transfer system 16g and the second transfer system 58g are chutes. The second transfer system 58g is used for the transportation of the oversized material 26g extracted from the material stream 12g to another location further downstream of the oversized material removal system 28g.

There is a short distance between the downstream side of the pulley separator 40g and the extraction chute 58g, creating a much smaller second gap 54g that only oversized material 26g easily slides over. Any material lOg from the material stream mistakenly goes over the pulley separator 40g will drop off the downstream side of the pulley separator 40g into the second gap 54g, sending it back to the material stream 12g.

Typically the first transfer system 16g and the second transfer system 58g are designed to have a channel shape or side walls so that a majority of the oversized material 26g remains on the chute and does not spill over the sides of the chute. It will be understood that any appropriate chute design will work for the first transfer system 16g and the second transfer system 58g.

Fig. 13 shows a flow chart of the method of removing oversized materials from a material stream. The material stream to be processed is first conveyed along a transfer system to a discharge end of that transfer system. Next, oversized material from the material stream is conveyed from the discharge end of the transfer system and over a pulley separator located downstream from the transfer system. Oversized material is conveyed across a gap that is situated between the transfer system and pulley separator and is at least as small as the length of oversized material being conveyed across the gap. After being conveyed past the pulley separator, the oversized material is conveyed onto a second transfer system downstream from the pulley separator.

Fig. 14 shows a flow chart of a second embodiment of the method of removing oversized materials from a material stream. The material stream to be processed is first conveyed along a transfer system to a discharge end of that transfer system. Next, oversized material from the material stream are conveyed from the discharge end of the transfer system and over a pulley separator located downstream from the transfer system. Oversized material is conveyed across a gap that is situated between the transfer system and pulley separator and is at least as small as the length of oversized material being conveyed across the gap. After being conveyed past the pulley separator, the oversized material is conveyed onto a storage device downstream from the pulley separator.

This invention has been described with reference to several preferred embodiments. Many modifications and alterations will occur to others upon reading and understanding the preceding specification. It is intended that the invention be construed as including all such alterations and modifications in so far as they come within the scope of the appended claims or the equivalents of these claims.