Patent Publication Number: US-11390402-B2

Title: Vacuum apparatus for filling bulk containers

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     This application is a continuation of International Patent Application No. PCT/US2018/047529 filed Aug. 22, 2018 which claims the benefit of U.S. Provisional Patent Application Ser. No. 62/548,717 filed Aug. 22, 2017 entitled “VACUUM APPARATUS FOR FILLING BULK CONTAINERS” which is hereby incorporated by reference in its entirety to the extent not inconsistent. 
    
    
     FIELD OF THE INVENTION 
     The present invention relates generally to the filling of bags with material and more particularly pertains to an apparatus and method for vacuum filling bulk containers with material. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a front perspective view of a bulk container vacuum filling apparatus according to an embodiment of the present disclosure. 
         FIG. 2  is a top plan view of the bulk container vacuum filling apparatus of  FIG. 1 . 
         FIG. 3  is a side plan view of the bulk container vacuum filling apparatus of  FIG. 1 . 
         FIG. 4  is a flow chart showing one set of steps utilized in an embodiment of the present disclosure for filling a bulk container with material using the bulk container vacuum filling apparatus of  FIG. 1 . 
     
    
    
     DESCRIPTION OF THE ILLUSTRATED EMBODIMENTS 
     For the purposes of promoting an understanding of the principles of the disclosure, reference will now be made to the embodiments illustrated and specific language will be used to describe the same. It will nevertheless be understood that no limitation of the scope of the disclosure is thereby intended, such alterations, modifications, and further applications of the principles being contemplated as would normally occur to one skilled in the art to which the invention relates. 
       FIGS. 1-3  illustrate one embodiment of a bulk container vacuum filling apparatus  10 . The apparatus includes a vacuum filling unit  100  and a bag placer assembly  200  which work in combination to fill a bulk container with a desired material. 
     The desired material may be any material which is traditionally stored within a bag or container. Typically, the materials for which vacuum filling is used are refined materials. For example, fine powders and shaped particles are particularly well suited to vacuum filling as augers can disperse them into the air and/or damage their shape. For purposes on non-limiting example, materials which are particularly suitable for vacuum filling include silicas, carbon black, stearates, fibers (including ceramic and acrylic fibers), dried collagens, talc and powdered lead. In addition, vacuum filling can achieve a higher density within the desired container in a shorter period of time. In addition to time savings, this increased density can provide for enhanced stability and reduced space during shipment. 
     Vacuum filling unit  100  may be in the form of a vertical tower as shown in  FIGS. 1-3  and may include, among other components, the control logic for operating the bag placer assembly  200 . For a description of the various components that may be included within vacuum filling unit  100 , please refer to U.S. Pat. No. 4,351,373 entitled “System and Method for Filling Bag With Dry Powder” and U.S. Pat. No. 4,648,432 entitled “Vacuum Apparatus for Filling Bags With Particulate Material Including Dust Collector and Recycling of Collected Materials” the contents of each are hereby incorporated by reference to the extent not inconsistent. 
     In the illustrated embodiment, vacuum filling unit  100  includes connections to one or more of a vacuum source  122 , a pressurized air source (not shown), electrical power  124 , and a supply line for the material desired to be filled  126 . Vacuum filling unit also includes control lines and feedback lines (not shown) for interfacing with bag placer assembly  200 . Other connections, such as hydraulic lines, water lines or the like (not shown) may be included depending upon the desired configuration of vacuum filling unit  100  and the desired actuation of bag placer assembly  200 . 
     The bag placer assembly  200  of  FIGS. 1-3  is shown in one form which is sized so as to accommodate a flexible intermediate bulk container  20  (FIBC) (also known as a “bulk bag”). Bulk bag  20  is a widely utilized industrial container made of flexible fabric that is designed for storing and transporting dry, flowable products. Bulk bags, such as bulk bag  20 , may be made of thick woven polyethylene or polypropylene, either coated or uncoated, porous or non-porous, and normally measure between 32-48 inches in length, width or diameter and vary in height from 32 to 80 inches. Some bulk bags can expand to a larger dimension when filled. These bulk bags have a capacity that is normally around 2000 lbs., but depending upon their construction and the desired material to be contained, some units can store even more. Bulk bags are often made with either one, two or four lifting loops  22 . Transporting and loading of filled bulk bags may be done by placing the bulk bag  20  on a pallet  26  (such as a standard 48″×40″ pallet) and/or by lifting it from the attached lifting loops  22 . Emptying is made easy by a special opening (not shown) in the bottom such as a discharge spout, of which there are several options, or by simply cutting it open. While the filling of a bulk bag  20  is shown herein, the use of other large scale industrial containers within bag placer assembly  200  is contemplated and desired to be protected. 
     According to the illustrated embodiment, bag placer assembly  200  includes two sections, namely base portion  210  and movable portion  250 . Base portion  210  includes an outer housing  212  which is sized so as to at least partially contain a filled bulk bag  20 . In the illustrated form, outer housing  212  includes top portions  212   a , bottom portions  212   b  and three sidewalls  212   c . In one form, outer housing  212  is formed from a strong and rigid material such as steel. Further, the base portion  210  includes a reinforcing frame  214  so as to maintain its shape despite having a vacuum or elevated pressure applied therein. A seal  216  surround the open portions of outer housing  212  which, when in contact with the matching portion of movable portion  250  creates a sealed vacuum/pressure chamber  202 . Outer housing  212  may be in the form of a partial circle, square, octagon, hexagon, or some other desired shape. In the illustrated form, base portion  210  also includes guide tracks  218  which provide a path along which moveable portion  250  may travel. 
     Base portion  210  also includes a filler head  240  which is operable to establish an air-tight seal with the interior of bulk bag  20  as will be described later. In one form, filler head  240  is pivotally mounted to base portion  210  so as to be lifted out of the way during loading and removal of a bulk bag  20  (i.e. when moveable portion  250  is extended away from base portion  210 ) but lowered into place onto the top of bulk bag  20  during filling. In a further form, filler head  240  is actuated between these two positions (and may be held in place) by a linear actuator  242  or some other suitable mechanism. Filler head  240  is also in fluid communication with material supply line  126 . Filler head  240  may also be in fluid communication with vacuum source  122  and/or a pressurized air source to enable the control of the pressure within the bulk bag  20  at various stages of the bag filling process. Additionally, in one form, filler head  240  includes sensors, such as a temperature sensor, a pressure sensor, and a humidity sensor (hidden from view) for providing real-time feedback to vacuum filling unit  100  via feedback lines (not shown). 
     Moveable portion  250  includes an outer housing  252  which is shaped so as to mate with outer housing  212  to fully enclose vacuum/pressure chamber  202 . Outer housing  252  is sized so as to at least partially contain a filled bulk bag  20 . In various forms, the outer housing  252  of moveable portion  250  forms half of the exterior of vacuum/pressure chamber  202 . In various other forms, the outer housing  252  of moveable portion  250  forms less than half of the exterior of vacuum/pressure chamber  202 . In certain forms, the outer housing  252  of moveable portion  250  has a distal size  254  along distal sidewall  252   c  which is greater than the width of bulk bag  20  and has a proximal size  255 , at least along the top  252   a , which is less than the width of bulk bag  20 . In one further form, the outer housing  212  has a width that is greater than distal size  254 . This relationship between distal size  254  and proximal size  255  and the size of outer housing  212  enables the moveable portion  250  to be easily slid away from base portion  210  despite the bulk bag  20  (contained therein) being filled to its maximum capacity. 
     In the illustrated form, outer housing  252  is in the shape of a wedge and includes a top portion  252   a , a bottom portion  252   b  and a sidewall  252   c . As with outer housing  212 , outer housing  252  may similarly be formed from a strong and rigid material such as steel. Further, the moveable portion  250  includes a reinforcing frame  256  so as to maintain the shape of outer housing  252  despite having a vacuum or elevated pressure applied therein. Reinforcing frame  256  may also provide support for the bulk bag  20  during filling. For example, reinforcing frame may include one or more hooks/clamps  258  which can be used to manually (or with a power-assist) connect to lifting loops  22  so as to provide either partial or full support for bulk bag  20 . In the illustrated form, top portion  252   a  includes an opening  260  which is surrounded by a collar  262  to which the opening bulk bag  20  may be securely mounted. Also in the illustrated form, wheels (not shown) are mounted to the underside of bottom portion  252   b  to enable the moveable portion  250  to move relative to base portion  200 , such as by rolling on guide tracks  218 . 
     As will be appreciated by one of skill in the art, moveable portion  250  may work in conjunction with seal  216  to provide an air-tight seal for the vacuum/pressure chamber  202  formed when base portion  210  and moveable portion  250  are positioned together. In alternative forms, seal  216  may be placed, in whole or in part, on the moveable portion  250  as opposed to base portion  210 . In another form, both portions may include cooperative elements which work together to provide the desired seal. In addition, bag placer portion  200  may include latches, clamps or some other mechanism to ensure that base portion  210  and moveable portion  250  remain in proper position with one another during use, particularly when an elevated pressure is desired within vacuum/pressure chamber  202 . Outer housing  212  may be in the form of a partial circle, square, octagon, hexagon, or some other desired shape. In the illustrated form, base portion  210  also includes guide tracks  218  which provide a path along which moveable portion  250  may travel. 
     In one form, bag placer assembly  200  also includes one or more scales or load cells (not shown) which are utilized to determine when the bulk bag  20  has been properly filled with the desired weight of material. In the illustrated form, one or more load cells are mounted to the base portion  210  such that they support the weight of the moveable portion  250  such that the increased weight of that portion may be determined during the filling operation. In an alternate form, one or more load cells are mounted beneath the moveable portion  250  such that the increased weight of that portion may be determined during the filling operation. In other forms, the bulk bag may be fully suspended so that one or more load cells may be placed in line with the straps  22  from which the bulk bag  20  hangs. 
     In alternative or additional forms, the bulk bag  20  may be placed upon a pallet  26  or other support structure to facilitate its removal once filled. This is advantageous as an empty bulk bag  20  can weigh as little as five pounds, but the same bag can weigh two-thousand pounds or more when filled. When the bulk bag is placed onto a support structure prior to being filled, the unique extension and wedge shape of moveable portion enables a forklift or other suitable machinery to easily access the pallet or support structure to remove the bulk bag  20 . In an alternate form, the apparatus  10  may include a plurality of moveable portions, such as moveable portion  250 , which are each rotated in sequentially, such as on a track or carousel, to sequentially or selectively combine with vacuum filling unit  100  so as to increase the throughput of the apparatus  10  by minimizing the downtime resulting from bulk bag placement and/or removal. Each moveable portion in such a series may be an individual unit, or may be a part of a chain or conveyor system. 
     Once properly installed and connected to the required inputs, the operation of the apparatus  10 , according to one form, is illustrated in  FIG. 4 . The process  400  begins at start with the placement of a bulk bag  20  within the moveable portion of bag placer assembly  200  (stage  402 ). The bulk bag  20  is connected to the bag placement portion, such as by manually connecting the loops  22  of bulk bag  20  to its support hooks/clamps  258  and the fill spout  23  through the opening  260  and to collar  262 . Once the bulk bag  20  is properly connected, the moveable portion  250  slides along guide tracks  218 , which may occur manually or by automation (using a winch or the like), in order to combine with base portion  210  to form a fully enclosed vacuum/pressure chamber  202  (stage  404 ). Once the moveable portion  250  is in its fully retracted position, the filler head  240  is moved into place on top of the bulk bag  20  (stage  406 ). The filler head  240  interfaces with collar  262  to establish an airtight seal between the filler head  240  and the vacuum/pressure chamber  202 . In the case of an impermeable bulk bag  20 , the filler head  240  may also establish an airtight seal with the internal area of bulk bag  20 . In order to ensure that the proper airtight seal has been achieved, and to avoid the potential mess that can occur if not, the apparatus  10 , as controlled by the vacuum filling unit  100 , performs a series of tests to confirm that vacuum/pressure chamber  202  is properly sealed (stage  408 ). These tests may include repeatedly pressurizing and/or drawing a vacuum within the vacuum/pressure chamber  202  and subsequently confirming that the pressure remains constant over a selected period of time. Alternatively or additionally, apparatus  10  may also perform a similar test within bulk bag  20  so as to confirm both the strength and integrity of the bag (stage  410 ). In another form, apparatus  10  may establish one pressure within vacuum/pressure chamber  202  and a different pressure within the interior of bulk bag  20  (such as applying an elevated pressure within the interior of the bulk bag and drawing a vacuum within the vacuum/pressure chamber  202 ). Measuring these two differing pressures and their persistence can indicate any potential problems. These types of testing, either alone or in combination, can avoid the messy situation where material is filled into a torn or defective container. 
     Once these preliminary tests have been satisfactorily completed, the actual filling process commences with the apparatus  10  establishing the desired environmental conditions within the vacuum/pressure chamber  202  and/or the interior of the bulk bag  20  (stage  412 ). The desired conditions may vary significantly depending upon the type of material which is selected for placement within the bulk bag  20  or other container. For example, when filling with less dense materials the apparatus  10  may establish a lower pressure within the vacuum/pressure chamber  202  relative to that in the interior of the bulk bag  20  so as to inflate the bulk bag  20 . This may include the use of either an elevated pressure or a partial vacuum, so long as the desired ratio is maintained. Alternatively, for more dense products, the apparatus  10  may establish a higher pressure within the vacuum/pressure chamber  202  relative to that in the interior of the bulk bag  20  so as to allow the material to slowly expand the bulk bag  20  to create a bellow type effect which will enable material to be drawn into the bulk bag  20  quicker. Once the initial environmental conditions are established, the filler head  240  being supplied material from the material supply line  126  into the interior of bulk bag  20  (stage  414 ). 
     In a further form, periodically throughout at least a portion of the remaining process the apparatus  10  monitors the desired pressure within each of the vacuum/pressure chamber  202  and the interior of the bulk bag  20  (stage  416 ). In the event either of these pressures is outside of the expected range, the apparatus  10  shuts down and signals an alert (stage  417 ). 
     Once a certain amount of the desired material has been placed into the bulk bag  20  (as determined by differential weights provided by the scales or load cells), or after a set period of time, the apparatus  10  establishes a second desired environmental condition within the vacuum/pressure chamber  202  and/or the interior of the bulk bag  20  (stage  418 ). The second desired conditions vary from the initial conditions under which filling began may also vary depending upon the type of material which is selected for placement within the bulk bag  20  or other container. For example, for less dense products the apparatus  10  may utilize may periodically provide an elevated pressure, either within the vacuum/pressure chamber  202  and/or the interior of the bulk bag  20  to enhance compaction of the material. Alternatively, for more dense products, this process may not be needed when filling denser materials which provide adequate packing on their own and as such a vacuum may be maintained within the vacuum pressure chamber  202  throughout the process. Once the second environmental conditions are established, the filler head  240  resumes supplying material from the material supply line  126  into the interior of bulk bag  20  (stage  420 ). In some forms, the filler head  240  is controlled so as to supply material at a second flow rate, which may be higher or lower than the initial flow rate, so as to more efficiently fill the bulk bag  20 . 
     Once the process reaches a certain point, the apparatus  10  continuously monitors the weight of the bulk bag  20  and its contents (as determined by differential weights provided by the scales or load cells) to determine when the full weight of material has been dispensed (stage  422 ). When this condition is met, the apparatus  10  stops dispensing material (stage  424 ). With the bag now full, the apparatus  10  safely returns the pressure within the vacuum/pressure chamber  202  and/or the interior of bulk bag  20  to normal environmental conditions (stage  426 ). The filler head  240  then retracts (stage  428 ) and the moveable portion  250  slides along guide tracks  218 , which may occur manually or by automation (using a winch or the like), to its fully extended position away from base portion  210  (stage  430 ). This enables the bulk bag  20  to be removed therefrom, such as by using a forklift, skid steer or the like, or for the moveable portion  250  to be moved away so as to make room for the next moveable portion  250  to take its place in a serial filling process. 
     While the invention has been illustrated and described in detail in the drawings and foregoing description, the same is to be considered as illustrative and not restrictive in character, it being understood that only the preferred embodiment has been shown and described and that all changes and modifications that come within the spirit of the invention are desired to be protected.