This invention relates generally to the removal and separation of materials from containers and more particularly to a self cleaning bag breaking machine that allows broken bags to be easily separated from the contents contained inside the bag.

Several limitations exist in present efforts to recycle trash and compost materials such as yard debris. For example, compost materials must be bagged and laid out in front of a residence for pickup. Because yard debris is rather heavy when accumulated together or when wet, the container used for holding the debris must be made from a rather strong material. If the container is made from a biodegradable material, such as paper, the paper must, therefore, be extremely thick to adequately support the heavy yard debris contained inside. Heavy paper bags, however, are expensive and further add to the land fill. In addition, paper bags get wet when exposed to the environment and in turn have a tendency to break when transferred from the lawn of a residence to a refuse truck.

Plastic bags are generally stronger than paper bags and are, therefore, capable of retaining more refuse using less material than a paper bag. However, plastic bags are not quickly biodegradable. Plastic

bags are typically shredded to remove the materials contained inside. However, if the plastic bag is used for holding compost or other recyclable materials, the shredded pieces of the plastic bag will be inter-mixed with the compost materials previously contained inside the plastic bag. Therefore, plastic bags cannot be used for holding compost or other recyclable materials.

For example, systems have been established in many municipalities for recycling recyclable materials such as plastic, glass and aluminum. A major effort involved with the recycling process involves, first, removing the trash and other recyclable materials from the trash bag and then separating out the different recyclable materials removed from the trash bag. Currently, trash and other recyclable materials are separated by throwing trash bags containing trash and other recyclable materials onto a set of sharp cutting blades. The blades shred the bags into hundreds of tiny pieces so that the contents of the bag fall out of the bag and onto a conveyer. The different recyclable materials are then separated. Slicing plastic or paper bags, however, does not always effectively remove all the contents from the bag. For example, the knives may only slice portions of the bag, essentially turning the bag into a net that still retains many larger objects.

To ensure that the contents of the bag are removed, the cutting blades are designed to completely shred the bag. However, when a trash bag is shredded, the hundreds of tiny pieces are intermingled with the

trash and other recyclable materials previously stored inside the bag. Therefore, the task of separating out the different recyclable materials from the bag material becomes more time consuming and costly. In addition, plastic bags are a recyclable resource that cannot be effectively recycled due in major part to the cost involved with gathering the small shredded pieces.

Present debaggers are also easily clogged with plastic bags and additional refuse that attaches around the blades and other cutting apparatus. The debaggers must, therefore, be continuously down and cleaned out reducing system throughput and increasing recycling costs.

A wide variety of materials and sizes of containers are used to store trash and other recyclable materials. For example, trash and other recyclable materials are stored in small plastic grocery bags, paper bags, and in large 30 gallon plastic bags. Debagging equipment designed for processing 30 gallon plastic bags is often not effective in removing materials from smaller grocery bags. For example, smaller bags can slip through the blades of the debagging equipment and remain intact when dropped onto a conveyer. Thus, a debagging system must be readjusted or separate systems used according to the size of the trash bags.

Accordingly, a need remains for a low cost self cleaning debagging machine that can effectively remove materials from a wide variety of trash bag sizes and materials.

SUMMARY OF THE INVENTION

It is, therefore, an object of the invention is to increase the adaptability of separation systems to remove trash and other recyclable materials from a wider variety of trash bags.

Another object of the invention is to reduce the amount of time and money required to separate trash bags from the materials contained inside the trash bag. A further object of the invention is to reduce the time and effort required to maintain a trash and other recyclable material separation system in an operating condition.

A trash and other recyclable material separation system tears apart bags in a manner that ensures that the contents of the bag fall out onto a conveyer while at the same time maintaining the bag in substantially one piece. The bag is dropped onto two cylinders that rotate in opposite directions. The first cylinder hooks the bag with a set of fins and then presents the bag to a second set of fins protruding from the second cylinder.

The first set of fins rotate at a relatively slow speed and the second set of fins rotate in an opposite direction at a relatively high speed. The second set of fins have relatively dull tips that instead of cutting the bag actually pull the bag apart. The speed differential between the first and second set of fins serve to stretch the bag apart until the bag eventually

breaks. Because the bag is stretched to such an extreme, a large tear is created in the bag that readily allows all the contents inside the bag to fall out. One advantage of the system is that the bag remains in substantially one piece. Thus, the bag can be quickly and easily removed from the other contents dislodged from the bag.

The shape of the fins in combination with the direction of fin rotation allow the system to automatically clean itself. For example, after the bag is broken, the bag may remain attached onto the first set of fins. The second set of fins automatically pull the bag off the first set of fins onto the receiving conveyer. In addition, the rotation of the first and second set of fins naturally force materials down onto the conveyer. Thus, the system does not have to be continuously down to be unclogged.

A set of steel fingers are attached between adjacent fins and hook onto small bags that could otherwise slip though the system without being broken. Each finger is fabricated from a piece of spring steel that slows the decent of the bag enough for the second set of fins to pull the bag apart. Thus, the system is effective in breaking both large and small bags without having to readjust the fin spacing.

The foregoing and other objects, features and advantages of the invention will become more readily apparent from the following detailed description of a preferred embodiment of the invention which proceeds

with reference to the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a front elevation view of a trash and recyclable material separation system according to the invention.

FIG. 2 is a top plan view taken along lines 2-2 in FIG. 1.

FIG. 3 is a partial front section view taken along lines 3-3 in FIG. 2 showing dual cylinders prior to receiving a container.

FIG. 4 is an isolated side view of the cylinders in FIG. 3 shown while initially receiving the container.

FIG. 5 is an isolated side view of the cylinders of FIG. 3 shown while ripping the container.

FIG. 6 is an isolated side view of the cylinders of FIG. 3 shown while discarding the container.

DETAILED DESCRIPTION

FIG. 1 is a front elevation view of a trash and recyclable material separation system 12 according to the invention. A conveyer 14 moves inside an enclosure

15 transporting trash bags (see FIG. 3) into a receiving shute 16. The trash bags fall through shute

16 into a bin 18 containing cylinders that break open the trash bags. The broken bags and the contents of the bags are discharged out through the bottom of bin 18 through a discharge shute 20 onto a conveyer 28. The cylinders inside bin 18 are operated by a first drive

system 24 and a second drive system 26. A platform 22 supports the bin 18 and allows personnel, to easily access the trash and recyclable material separation system. FIG. 2 is a top plan view of the trash and recyclable material separation system 12 taken along lines 2-2 in FIG. 1. An opening 40 in the top of bin 18 receives the bags dropped into receiving shut 16 (FIG. 1) . A first elongated cylinder 32 extends from a front side 31 to a back side 33 of bin 18. A first set of fins 34 are spaced at equal distances across and around the first cylinder 32. Multiple fingers 36 reside around cylinder 32 on opposite sides of each fin 34. Each finger 36 is attached to the cylinder 32 via an elastic member 37 mounted near the base of the fin 34. The finger is angled laterally away from the base of the associated fin.

A second elongated cylinder 30 extends from the front side 31 to back side 33 of bin 18 in a parallel alignment with cylinder 32. A second set of fins 38 are spaced both across and around the second cylinder 30. Fingers 38 are aligned in a parallel arrangement half way between laterally adjacent fins 34 on the first cylinder 32. Fins 34 and the first cylinder 32 are referred to as a catch mechanism having catch fins 34. Cylinder 30 and fins 38 are referred to as a pull mechanism having pull fins 38.

The first drive system 24 includes a motor 42 that drives a chain 44 in turn rotating a shaft 46. Shaft 46 rotates cylinder 32 about an elongated central axis.

Drive system 26 includes a motor 48 that drives shaft 50 in turn rotating cylinder 30. The motor controllers used to control the speed and direction of rotation of motors 42 and 48 are known to those skilled in the art and are,therefore, not described in detail.

FIG. 3 is a partial front section view taken along lines 3-3 in FIG. 2 showing cylinders 32 and 30 prior to receiving a plastic bag 52. It can be seen that the fins 34 and 38 are spaced radially about cylinders 32 and 30, respectively. Both fins 34 and 38 each comprises a first side 54 extending substantially perpendicular from the cylinder up to a fin tip 58. A second convex side 56 extends from a substantially tangential relationship with the cylinder up to the fin tip 58. The first and second sides of each fin 38 on cylinder 30 is shaped in substantially the same manner on the fins 34 on cylinder 32 except that the convex side on fins 34 are sloped at a greater angle.

Each fin on cylinder 30 has a tip 58 with a radius of approximately 3/16ths inches. Each fin 34 and 38 is approximately between one inch and one and one-half inches thick. Motor 42 rotates cylinder 32 in a clock¬ wise directions and motor 48 rotates cylinder 30 in a counter clock-wise direction. After traveling up conveyer 14, Bag 52 is deposited through receiving shute 16 onto the top of fins 34 and 38. The shape, thickness and rotational speed of the fins are important for ensuring that bag 52 is ripped open as opposed to being shred open. For example, if too thin, the fins will slice bag 52 into a

net and not allow all the contents in the bag to fall out. In addition, if bag 52 is shredded, little pieces of the bag will drop onto the conveyer 28 (FIG. 1) making separation of the bag 52 from the other contents difficult.

Cylinder 32 and 30 are, therefore, rotated at different speeds according to the type of bag material and the type of materials inside the bag. In one example, cylinder 32 is rotated between 2-15 rotations per minute (RPM's) and cylinder 30 is rotated multiple times faster than cylinder 32. The rotational speed ratio between cylinder 32 and 30 are again changed according to the specific materials being processed. FIG. 4 is an isolated side view of the cylinders in FIG. 3 shown while initially receiving bag 52. Upon falling into bin 18, bag 52 is hooked by fins 34 at a first location 60. Fins 34 serve to slow the speed of bag 52 while descending through shute 16. The clock¬ wise rotation of fins 34 move bag 52 to the right and downward presenting the bag to fins 38.

The second set of fins 38 rotate in a counter clock-wise direction with tip 58 angled toward bag 52. Tip 58 hooks into a second location 62 on bag 52. The relatively blunt tip 58 on fins 38 hook into bag 52 without slicing through the plastic material. Cylinder 30 is rotated at a substantially greater speed than cylinder 32. Thus, fins 38 pull location 62 on bag 52 down much faster than fins 34 allow bag location 60 do descend. Thus, fins 38 stretch bag locations 62 and 60 apart until bag 52 eventually tears as shown in FIG. 5.

Referring to FIG. 5, fins 34 and 38 stretch the plastic material of bag 52 until bag 52 eventually tears. Because the bag is in a stretched condition, a large tear is created in bag 52 that allows all the contents 64 in bag 52 to fall out. Cylinders 30 and 32 are spaced a sufficient distance apart so that bottles, cans and other recyclable materials fall between the two cylinders onto conveyer 28 (FIG. 1) . Cylinder 32 also helps push the contents 64 and bag 52 through the space between cylinders 32 and 30. Because the bag 52 is torn and not shredded, the bag remains in substantially one piece.

FIG. 6 shows the trash bag 52 after trash bag 52 is removed. After removal of contents 64, in many instances bag 52 remains attached to fins 34. However, when a fin 65 rotates downward at an appropriate angle as shown in FIG. 6, fins 38 will pull bag 52 off of fin 65. Bag 52 then drops onto conveyer 28 (FIG. 1) in one single piece. Thus, fins 38 in addition to breaking bag 52, also serve to help remove bags and assorted accumulating materials attached onto fins 34.

Motors 42 and 48 (FIG. 2) include control units that adjust the speed of cylinders 32 and 30, respectively, according to the type of materials dropped into bin 18. Thus, the speed of fins 34 and 38 properly tear bags regardless of the type of bag material. Motor control systems that maintain a constant shaft torque are known to those with average skill in the art and are, therefore, not described in detail.

Referring back to FIGS. 2 and 3, fingers 36 prevent small bags from squeezing between adjacent fins on cylinder 32. For example, small grocery bags could be potentially pushed between fins 32 without being torn by fins 38. However, fingers 36 ensure that small bags will be hooked prior to transcending between the fins 34.

A bag squeezing between the fins 34 will hook onto the fingers 36 bending the fingers 36 slightly downward. The fingers 36 slow the decent of the bag until fins 38 pull the bag apart in a manner similar to that described above. After the bag is broken apart, fingers 36 spring back into their original position. Fingers 36 are optional and may be removed if only large bags are deposited into bin 18 or if fins 34 are placed closer together.

The number of fins, the spacing distance between fins, and the spacing distance between shafts can all be varied according to the type of trash or other recyclable materials being processed. However, using fingers 36 allow a wider variety of materials and trash bags to be processed with a single system arrangement. The fins 34 and 38 operate as described above equally as well for paper or plastic bags of variable thicknesses.

The system described above removes material from a wide variety of bags having different sizes, shapes and made from different materials while maintaining the broken bag in a single unitary piece. Because the bag remains in one piece, the broken bag is easily

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separated from the other contents previously contained in the bag. By being self cleaning, the system minimizes machine down time and maintenance.

Having described and illustrated the principles of the invention in a preferred embodiment thereof, it should be apparent that the invention can be modified in arrangement and detail without departing from such principles. I claim all modifications and variation coming within the spirit and scope of the following claims.