IL164709A - Apparatus for automatically lifting, slitting and fully emptying bags - Google Patents

Description

APPARATUS FOR AUTOMATICALLY LIFTING, SLITTING, AND FULLY EMPTYING BAGS APPARATUS FOR AUTOMATICALLY LIFTING, SLITTING, AND FULLY EMPTYING BAGS FIELD OF THE INVENTION The present invention relates to automatic machinery for handling bag splitting. More particularly, the present invention relates to automatic lifting bags, slitting, and emptying them so as to minimize lose of material.

BACKGROUND OF THE INVENTION In most of the industries in fields such as polymers, pharmaceuticals, food, and chemistry, raw material is delivered in medium to large sized bags. Typically, the bags are received on pallets and the raw material from the bags is being dispensed into processing apparatii in a manual manner by a worker that slits the bag using a knife and transferring the material to a receiver such as a funnel. Since the bags are relatively heavy, emptying the material into the processing machine by the worker that lifts the bags one after the other is the "bottle neck" of the processing progress. Moreover, raw material, which can be very expensive, is being lost throughout the process of emptying the bags into a receiver since the worker has to carry the sliced bag and to shake it on top of the receiver or the funnel.

During attempts to improve the process, automatic machinery were applied. WAM from Italy is manufacturing an automatic shredder bag splitter and Morray is manufacturing an automatic bag splitting machine. Both machinery has inherent drawbacks and mainly in the form of shredding and splitting the bag. The bag full of raw material is inserted into the machine that shreds the bag so as to allow all the raw material to be dispensed into the processing apparatus. Due to the form of shredding, small pieces from the shredded bag may enter the processing apparatus along with the raw material, a feature that is implausible in most industries. Moreover, the process does not eliminate the need of the worker that places the bags in the machine and this process becomes a new "bottle neck" for the progress of the processing of the raw material.

There is a vast need in many of the industries using raw materials in their processing for an apparatus that will quickly, effectively and efficiently slit the bags and empty them into a receiver of the processing apparatus.

SUMMARY OF THE INVENTION It is an object of the present invention to provide an apparatus and method for automatically gripping, lifting, slitting and emptying one or more of the topmost bags from a stack of bags, such as of bags arranged on top of a pallet.

It is another object of the present invention to provide an apparatus and method for simultaneously discharging raw material off a plurality of bags altogether without considering the size of the bags and the arrangement of the bags in a stack.

It is yet another object of the present invention to provide an apparatus and method for sharply slitting the bags without any possibility of mixing bags' debris with the raw material discharged.

An addition object of the present invention is to provide an apparatus and method for emptying the bags that minimize losses of raw material.

It is thus provided in accordance with the present invention, an apparatus for automatically lifting, slitting, and emptying stacked bags, the apparatus including: an upper frame having a first end and a second end; a gripping subunit adapted to move along said upper frame from said first end to said second end and vice versa, wherein said gripping subunit is adapted to lift at least one of the stacked bags which are placed beneath said first end; a slitting subunit provided beneath said second end and wherein said slitting unit is adapted to slit the bags when said gripper unit with the bags passes on top of said slitting subunit. Furthermore, in accordance with a preferred embodiment of the present invention, said gripping subunit comprises: an actuation means adapted to move along said upper frame and shake; an extendable arm connected to said actuation means, beneath it; a gripper connected to said extendable arm wherein said gripper has a plurality of hooks adapted to grip one or more bags.

Furthermore, in accordance with another preferred embodiment of the present invention, the hooks are adapted to move between two positions: a first position in which said hooks are extended so as to grab the bags and a second position in which said hooks are contracted.

Furthermore, in accordance with another preferred embodiment of the present invention, said slitting subunit is provided with several blades that are aligned in a raw perpendicular to the movement of said gripping subunit.

Furthermore, in accordance with another preferred embodiment of the present invention, said blades are rotary blades.

Furthermore, in accordance with another preferred embodiment of the present invention, said slitting subunit is provided with several rods that are aligned with said several blades.

Furthermore, in accordance with another preferred embodiment of the present invention, the apparatus further comprises a container adapted to receive bags' debris.

Furthermore, in accordance with another preferred embodiment of the present invention, the apparatus further includes a controller adapted to control the movement of said gripping subunit.

Furthermore, in accordance with another preferred embodiment of the present invention, the apparatus further includes a base frame onto which upper frame is connected wherein said base frame is provided with wheels as well as firm legs.

It is also provided in accordance with the present invention, a method for automatically gripping, lifting, slitting, and emptying stacked bags of raw material, by means of an apparatus having a gripping subunit and a slitting and emptying subunit; the method includes the steps of: forcing a plurality of hooks of the gripping subunit into one or more of the stacked bags thereby gripping the bag or bags; lifting the gripped bag or bags off the stack; carrying the gripped bag or bags across blades of the slitting and emptying subunit such that the bag or bags are slitted by the blades and a few stripes of bags' debris are engaged between rods of the slitting subunit, which are aligned with the blades; reciprocally shaking either the slitted bags, or the stripes of bags' debris engaged between the rods thereby discharging leftover disposed on the stripes; removing bags' debris off the slitting and emptying subunit by means of the gripping subunit.

BRIEF DESCRIPTION OF THE FIGURES In order to better understand the present invention and appreciate its practical applications, the following Figures are attached and references herein. Like components are denoted by like reference numerals.

It should be noted that the figures are given as examples and preferred embodiments only and in no way limit the scope of the present invention as defined in the appending Description and Claims.

Fig. 1 illustrates an isometric view of an automatic apparatus for slitting and fully emptying bags in accordance with a preferred embodiment of the present invention; Fig. 2A illustrates a side view of a gripper system incorporated in the automatic apparatus shown in Figure 1 , with withdrawn hooks; Fig. 2B illustrates the gripper system shown in Figure 2a, with drawn hooks; Fig. 3 illustrates a frontal view of the slitting and emptying subunit, while cutting bags that are gripped by the gripper system shown in Figures 2A and B.

Fig. 4 illustrates an isometric view of a slitting and emptying subunit incorporated in the automatic apparatus shown in Fig. 1 ; Fig. 5 illustrates an isometric view of a slitting and emptying subunit in accordance with a preferred embodiment of the present invention; Fig. 6 illustrates a side view of the apparatus shown in Fig. 1 , while the leftover bags are being compressed; DETAILED DESCRIPTION OF THE INEVNTION AND FIGURES The present invention provides a unique and novel apparatus for splitting in an effective and quick manner bags with raw material and emptying them so as for example to dispense the raw material into a receiver of a processing apparatus,. The apparatus of the present invention is adapted to automatically lift the bags from a pallet, slitting the bags so as to discharge the raw material and emptying the bags into a receiver of the processing apparatus. The apparatus of the present invention comprises several sub-units, each adapted to handle a certain task in the overall process. The sub-units are organized in a manner that facilitates full cooperation between the units and effectiveness. Am important feature of the apparatus is its ability to simultaneously handle several bags without considering the size of the bags and the arrangement of the bags on a pallet. Specifically, the apparatus is adapted to simultaneously handle a number of bags of a total weight of 250 Kg or more. The apparatus of the invention releases a "bottle neck" of a typically heavily loaded with labor processes of emptying bags. Excluding the delivery of the bags to the apparatus, which is typically carried out by means of a forklift truck, the process according to the present invention is fully automatic and substantially requires minute manual intervention.

As mentioned herein before, one of the main problems in existing apparatii that attempt to automatically shred and empty bags is in slices of bags that are being discharged with the raw material. The apparatus of the present invention is adapted to sharply slit the bags (possibly several bags altogether) without any possibility of mixing pieces of the bag into the raw material. Another drawback in manual emptying or automatic emptying the bags is in leftovers of raw material that is being left in pockets or folds of the bag. The present invention is adapted to allow total emptying of the bags without significant loss of raw material.

Reference is now made to Fig. 1 illustrating an isometric view of an automatic apparatus for slitting and fully emptying bags in accordance with a preferred embodiment of the present invention. The apparatus of the present invention comprises a deck 10 located at its bottom portion. Deck 10 is adapted to receive a plurality of bags 12 that are preferably organized in several stories loaded over a palette, wherein each story is provided with a few bags. The bags are delivered onto the deck preferably by a forklift truck (not shown in the Figures). Deck 10 is optionally provided with a container 14 adapted to receive empty bags and/or bags' debris.

The apparatus is further provided with a movable gripping subunit 20 that is adapted primarily to move coaxial with the upper frame along a rail 22 from a first end of upper frame 23 to a second end of this upper frame, grip bags 12 lift them from deck 10, carry them to slitting and emptying subunit 30, and dispose off the empty bags by dropping them into container 14, and repeatedly go on. Rail 22 is located on the upper frame 23 that is mounted on top of a base frame 25. Gripping subunit 20 comprises an actuation means 24 adapted to move along rail 22, and an extendable arm 26 adapted to adjust the height of the gripper 28 attached at the bottom of gripping subunit 20. In Fig. 1 the gripping subunit 20 is shown in a halfway position between the plurality of bags 12 and the slitting and emptying subunit 30 while gripper 28 grips a story of bags 29 that were lifted off the stacked bags 12.

Reference is now made to Figs 2A and 2B illustrating a side view of a gripper according to a preferred embodiment of the present invention, such as is incorporated in the apparatus of Fig. 1. Gripper 28 is provided with a plurality of turnable curved hooks 42 that are arranged in rows, each raw is provided with a number of couples of hooks. A pneumatic cylinder 44 attached along the rows actuates the turning of hooks 42. Hooks 42 rotate between two positions: a first position shown in Fig. 2A in which hooks 42 are withdrawn and a second position (shown in Fig. 2B) in which hooks 42 are downwardly drawn.

When the gripping subunit is positioned above a stack of bags, gripper 28 is lowered down by means of its extendable arm. When the gripper touches, or reaches a close proximity to the upper layer of bags, its hooks are drawn or extended out by being rotated, pinch the topside of the bags of the upper layer and grip it so as to allow its lifting. The spacing between two adjacent couples of hooks in a row and the spacing between the rows of hooks are such that each of the bags in the upper layer of stacked bags is gripped with a significant number of couples of hooks of at least two different rows. Therefore the gripper 28 need not be aligned to the layers of bags before gripping, and the bags need not be densely arranged in a layer. A pair of curved hooks of a couple respectively form an arc of a circle each centered at the axis of rotation of the respective hook when they are downwardly extended. Furthermore the pinched holes in a bag, which are respectively disposed on these circles, are not torn out by the extended hooks. Therefore a possibility of shreds being dropped down with the bag's content while the gripped bags are emptied is substantially minimized. The hooks need not be arcuate according to the invention, hooks shaped like a spike, lance, skewer, spear, prong, stylet, piercer or gimlet may serve for gripping as well. In such a case the hooks, which are downwardly tilted, are arranged in two arrays in which all the hooks of one array are pointed in the opposite direction from the hooks of the other array. As a result a gripped bag is pierced with a plurality of hooks such that a number of pairs of hooks are forced into a gripped bag, and the projections of the hooks of a pair cross each other. Withdrawing the hooks is accomplished by pulling off the hooks, whereas drawing is accomplished by downwardly extending them.

The frame 46 on which the rows of hooks are installed is optionally hanged on four load cells, not shown, which are connected to the frame 48 of the gripper. Therefore weighing of a raw material received is provided by the automatic apparatus for slitting and fully emptying bags in accordance with the present invention.

Optionally, gripper 28 can move in the horizontal plane so as to adjust itself to the stack of bags beneath it so that if one story has moved from some reason, the whole story will any way be lifted up since the gripper will adjust itself to the story location. A sensor 49 is provided in a bottom position of gripper 28 to ensure a proper positioning of the gripper enabling the hooks to grip all bags that are provided in the upper story without consideration of the particular arrangement of the bags or the number of bags that are arranged in the bags' upper story.

Reference is made again to Fig. 1. The apparatus of the present invention further comprises a slitting and emptying subunit 30 that is mounted on a side frame 32 attached to the upper frame 23 as well as to base frame 25. Gripping subunit 20 moves with gripped bags 29 towards the slitting and emptying subunit 30 while bags 29 pass over a row of rotary blades 34 so as to allow all bags to be cut by the blades. The blades rotate around an axis which is perpendicular to the movement of the gripping subunit. Therefore when the gripping subunit moves forwards, parallel slits are cut in the bottom of the bags. Receiver 36 is provided below blades 34. When gripping subunit 20 reaches a predetermined location above the receiver 36, it is shaken to allow the raw material to fall down into the receiver and to prevent leftovers of material within folds or on top of suspended bands of the slit bags.

The blades need not be rotary according to the invention. Blades like swards or shaped in any geometrical shape are suitable according to the invention as long as a sharp slit across the bags' wrappings is provided by passing the bags over the blades.

Reference is now made to Fig. 3 illustrating a frontal view of the slitting and emptying subunit, while cutting bags gripped by the gripper of Figs 2A and 2B. Gripping subunit 20 is forwarded along the rail located on top of the upper frame 23 towards the rotating blades 34. The rotating blades slit the gripped bags 29 while the gripper moves forwards. The raw material falls down into receiver 36 that is positioned beneath the blades and rods 59 aligned with them.

Reference is now made to Fig. 4 illustrating an isometric view of a slitting and emptying subunit according to a preferred embodiment of the present invention. Rods 60 are provided parallel and as a continuation of the rotary blades 34. Rotary blades 34 are actuated by motor 64. Since the bags are siltted in parallel cuts, bands of cut bags on which some of the bags' content resides are curved downwards in the spaces between any two adjacent rods. A Slight horizontal translation of the gripper perpendicular to the rods 60 in both directions pulls aside and accordingly tilts these bands. Leftover of material that might reside on top of bands of silted bags or in folds in the bag are charged by shaking the gripper when it reaches a predetermined location above the receiver. This shaking is carried gripper in perpendicular directions to the aligned rotary blades are employed so that the bags are not shredded and the slits in the bag are sharp and narrow. Therefore small pieces, or shreds, of the bag are avoided.

An alternative approach of discharging a leftover material in the siltted bags is described by reference to Fig. 5 in which a slicing and emptying device according to another preferred embodiment of the present invention is shown. This slitting and emptying subunit 80 consists of horizontally translating rods. Rods 82 are attached to a frame 84, which is off centered connected to a wheel 86 driven by a motor 88, by means of a connecting rod 90. Another motor 92 drives the rotating blades 94 which are disposed in front of the rods 82. Rotating wheel 86 induces a cyclic translation of rods 82 relative to the siltted bags which in turn tilts the bands of slitted bags. Therefore by shaking either the gripper, or the rods, the bags' content resided on the bands and in folds, or small pouches of a bag, is discharged.

Reference is now made to Fig. 6 illustrating a side view of the apparatus shown in Fig. 1 , while the empty bags are compressed. After emptying the bags by the slitting and emptying subunit 30, the gripping subunit 20 moves backwards to a predetermined location above the opening of container 14, hooks 42 are withdrawn and the empty bags are dropped into container 14. A heap of slitted bags tends to occupy a large volume. Therefore, occasionally when gripping subunit 20 moves with full bags 29 on its way towards the slitting and emptying subunit 30, when it reaches a predetermined location above the opening of container 14, extendable arm 26 extends down into container 14 and the current gripped layer of bags compresses the heap of empty bags inside the container. (The empty bags are not shown.) Alternatively the container for storing empty bags and/or bags' debris can be placed adjacent to the slitting and emptying device at a side opposing the stacked bags. In such a case the bags debris are released from the gripper immediately following their being emptied. The released bags' debris are left laid on top of slitting and emptying subunit untill the moment in which the following slitting and emptying cycle starts. The bags' debris are further pushed off the slitting and emptying subunit by means of a grate attached to the gripper at its side facing the slitting and emptying device.

Base frame 25 is supported by legs 96 that are firmly positioned on the floor; however, wheels 98 are provided so as to allow moving the apparatus from one place to another or in cases such as maintenance.

Optionally, funnel 100 is provided beneath receiver 36 so as to allow collection of the raw material to be delivered to a processing machine, a storage tank, or the like.

Control unit 104 is provided so as to control the operation and cooperation of both subunits - the gripping subunit and the slitting subunit as well as the operation of the whole apparatus. Controller 104 is preferably provided with display 106 and functional keys 108 so as to allow an operator to input operational data and operate the system.

It should be mentioned that in the gripping subunit, other grasping mechanism can be used instead of, or in addition to the hooks, vacuum nipples for example. This will disable the gripper from grabbing bags that are made of cloth, for example.

It should be clear that the description of the embodiments and attached Figures set forth in this specification serves only for a better understanding of the invention, without limiting its scope as covered by the following Claims.

It should also be clear that a person skilled in the art, after reading the present specification can make adjustments or amendments to the attached Figures and above described embodiments that would still be covered by the following Claims. 164907/3 13

Claims (1)

1. CLAIMS An apparatus for emptying bags comprising o a gripper having a plurality of pointed hooks for gripping at least one of said bags; o a bag slitting and emptying device, wherein said bag slitting and emptying device comprises • at least two parallel blades for slitting said at least one bag, and • at least two rods aligned in a row respectively with said blades. An apparatus for emptying bags as in claim 1 , wherein at least one of said plurality of pointed hooks has a first end pivotally attached to said gripper and a second tipped free end, and wherein a segment of said at least one of said plurality of pointed hooks is arcuate. An apparatus for emptying bags as in claim 1 , further comprising an upper frame having two ends, wherein said gripper is moveable along said upper frame from one of said two ends to the other end and vice versa, and wherein said gripper is vertically moveable in opposite directions relative to said upper frame. 164907/3 14 An apparatus for emptying bags as in claim 3, wherein said gripper is horizontally moveable in opposite directions sideways from said upper frame. An apparatus for emptying bags as in claim 1 , wherein said at least two rods are shakable. An apparatus for emptying bags as in claim 1 , further comprising a container for receiving debris. An apparatus for emptying bags as in claim 6, further comprising a grate for pushing debris off said slitting and emptying device. A method for emptying stacked bags, said method comprising the steps of a. gripping at least one bag of the topmost layer of said stacked bags by a plurality of pointed hooks; b. slitting said at least one bag by at least two parallel blades; c. horizontally displacing an upper surface of said at least one bag in a perpendicular direction relative to at least two rods, and wherein said at least two rods are aligned in a row respectively with said at least two parallel blades, and wherein said displacing is reciprocally accomplished. 164907/3 15 9. A method for emptying stacked bags as in claim 8, wherein said gripping comprises the steps of i) placing said plurality of hooks above said topmost layer, and ii) forcing at least two of said plurality of hooks into said at least one bag. 10. A method as in claim 9, wherein said forcing is accomplished by rotating, and wherein at least a segment of at least one of said hooks is arcuate, and wherein said arcuate segment rotation conforms with a circular path. 1 1. A method as in claim 8, wherein said horizontally displacing is accomplished by moving said at least one bag. 12. A method as in claim 8, wherein said horizontally displacing is accomplished by moving said at least two rods. 13. A method as in claim 8, further comprising releasing debris of said at least one bag immediately following said horizontally displacing. 14. A method as in claim 13, further comprising moving said plurality of hooks towards said stacked bags while releasing debris of said at least one bag, wherein said moving starts immediately following said horizontally displacing.