Patent Publication Number: US-7223058-B2

Title: Bulk bag discharging system assembly

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
   This application claims the benefit of U.S. Provisional Application No. 60/378,298, filed on May 6, 2002, the disclosure of which is hereby incorporated by reference in its entirety. 

   BACKGROUND OF THE INVENTION 
   Bulk bag discharging systems have been used to transfer materials, usually raw materials, from one container into another without contaminating the materials. Generally, bulk bag discharging systems lift a material-containing bag into a dispensing position. Once the bag is in position, an operator must somehow stretch the outlet portion of the bag material that is below a tie off point around a dispensing spout. This is extremely difficult in known bulk bag systems employing a dust free chamber around the dispensing spout because the dispensing spout is normally contained within a square chamber. When a dust free chamber is used, they only employ a single door on one side. As a result, there is no convenient way to seal the bag in a dust free manner because, before the bag is untied to release the contents, the loose bag material must be fitted around the dispensing spout, which is difficult if not impossible, for an operator when the only access point is a single door on one side of the chamber. The single door does not allow the operator to easily reach around the entire circumference of the spout and fit the loose bag material over the spout. 
   Additionally, prior bulk bag dispensing systems have used V-shaped impactors that run off one pneumatic cylinder and pinch together to squeeze the sides of the bulk bag, thereby preventing the formation of bridging/rat-holing, which is a condition whereby a material arches or bridges across a dispensing hole, resulting in sporadic flow or a complete cessation of flow. Massagers have also been used to help prevent rat-holing/bridging. The massagers used in the prior art are typically manufactured using square metal segments. As with the prior art impactors, the prior art massagers are typically positioned near the bottom of the bag and contact the bag on each side simultaneously. 
   Lastly, the prior art bulk bag dispensing apparatuses typically employ an iris type shut off valve above the dispensing aperture. Unfortunately, this design only allows the operator to stop the flow of material by closing the iris shut off valve when the material is flowing out of the bag. There simply is not enough strength in the prior art iris designs to close the container when the material itself is preventing the iris from closing. 
   Accordingly, there is a significant need for an easily operably, durable, heavy-duty bulk bag container discharging system, which can provide: an easily accessed dispensing chamber; a system for easily sealing the loose material of a bag container in a dust free fashion within the dispensing chamber; independently driven, adjustable impactors and massaging units, which will allow the operator to not only squeeze the bag using these systems but also rock the bag container back and forth in the same or different directions; and a flow stopping discharge system, which allows an operator to close the bag container at any time, including when the material is not flowing. 
   SUMMARY OF THE INVENTION 
   In one embodiment of the present invention, a material container discharge assembly includes: a main frame assembly having a hoist support engaged to the main frame assembly and a hoist moveably engaged with the hoist support; a material container transport component engaged to the hoist and adapted to engage a material container; at least two independently movable material container impactors engaged to the main frame assembly; a discharge receiving gate engaged to the main frame assembly having a material container receiving aperture and first, second, and third movable plates, where the first and third plates are movable between an open and closed position and further define a second plate receiving area for receiving the opposed second plate when the second plate and the first and third plates are in the closed position; and a substantially circular access chamber spaced below the material container receiving aperture and around a material receiving spout that includes at least two access doors on substantially opposite sides of the chamber that operate to substantially air tight seal when closed and a sealing system having a sealing device movable between a disengaged position and an engaged position, where the engaged position operates to seal the container in position over the spout. 
   In yet another embodiment of the present invention, a material container discharge assembly includes a main frame assembly and a discharge receiving gate engaged to the main frame assembly having a material container receiving aperture and first, second, and third substantially concave movable plates, where the first and third plates are movable between an open and closed position and further define a second plate receiving area for receiving the opposed second plate when the second plate and the first and third plates are in the closed position. 
   In another embodiment of the present invention, a material container discharge assembly includes: a main frame assembly; a material container receiving component engaged to the main frame assembly having a material container receiving aperture; and a substantially circular access chamber spaced below the material container receiving aperture having at least two access doors on substantially opposite sides of the chamber that operate to create a substantially air tight seal when closed. 
   In yet another embodiment of the present invention, a material container discharge assembly includes: a main frame assembly; a material container receiving component engaged to the main frame assembly having a material container receiving aperture and a spout; and a sealing system having a sealing ring that includes a metal ring engaged to a second ring and at least one pneumatic cylinder, where the sealing ring is movable between a disengaged position and an engaged position using at least one pneumatic cylinder and where the engaged position operates to seal the container in position over the spout. 
   These and other features, advantages and objects of the present invention will be further understood and appreciated by those skilled in the art by reference to the following specification, claims, and appended drawings. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
       FIG. 1  is a side perspective view of the material discharge assembly of the present invention showing the material bag/container being moved into position; 
       FIG. 2  is a front perspective view showing the material bag/container in the dispensing position within the material discharge assembly; 
       FIG. 3  is a side perspective view showing the material bag/container in the dispensing position within the material discharge assembly; 
       FIG. 4  is a perspective view of the material bag/container transport assembly of the present invention; 
       FIG. 5  is a perspective view of one of the independently movable material container impactors engaged to the main frame assembly; 
       FIG. 6  is a perspective view of the at least two independently movable material container massaging frames and the discharge receiving gate, which is shown in the open position; 
       FIG. 7  is a perspective view of the discharge receiving gate, where the receiving aperture is closed by the curved first and third plates matingly receiving a second curved plate; 
       FIG. 8  is a perspective view of the spout access chamber to access doors in the open position and showing the movable sealing assembly in the open and bag sealing position; 
       FIG. 9  is a perspective view of the spout access chamber, where the two access doors are closed; 
       FIG. 10  is a side view of the material discharge assembly showing a side view of bag conditioning impactors of an embodiment of the present invention; and 
       FIG. 11  is a side view of the material discharge assembly showing a front view of the bag conditioning impactors of an embodiment of the present invention. 
   

   DETAILED DESCRIPTION OF PREFERRED EMBODIMENT(S) 
   The discharge assembly  10  of the present invention typically includes a main frame assembly  12  that includes a hoist support  14  engaged to the main frame assembly  12  and a hoist  16  moveably engaged with the hoist support  14 ; a material container transport assembly  18  engaged to the hoist  16 , typically by a heavy-duty chain  20 ; at least two independently movable material container impactors  22  adjustably engaged to the main frame assembly to accommodate different sized soft-sided material containers (bags)  24 ; at least two independently movable material container massaging frames  26  engaged to the main frame assembly  12 ; a discharge receiving gate  28 ; and a spout access chamber  30 . 
   The main frame assembly  12  typically utilizes about three inch to about four inch diameter square tubing having about ¼ inch to about ⅝ inch thick walls about the perimeter of the main frame assembly  12 . These perimeter pieces  32  are typically continuously welded with one another to provide added strength. The main frame assembly  12  further includes a hoist support  14 , which is typically an I-beam engaged to the top of the main frame assembly  12 . The I-beam is typically about an eight inch S-flange, approximately  23  pound beam that conforms to ASTM A36 carbon steel specifications. The hoist I-beam is typically engaged to the main frame assembly  12  with an about one inch thick plasma cut mounting support bracket. The cross support members  34  are typically about 1½ by 1½ by about 1½ inch square metal segments. The cross support members  34  are typically continuously welded to the other portions of the main frame assembly  12  to provide optimum strength. While not preferred, the cross support members  34  may be anchored to the structural members by any other suitable means, such as bolts and angle irons. 
   The hoist  16  is typically a heavy-duty hoist capable of lifting loads from about 1 ton to about 3 tons. Typically, the hoist is controlled with a conventional controller  17 . The lifting strength of the hoist may be increased or decreased to any strength, depending on user need. The hoist  16  is operably coupled with a heavy-duty chain  20  or other lifting member. The heavy-duty chain  20  typically employs a steel hook  36 . The steel hook  36  is typically mounted to the heavy-duty chain  20  such that it is allowed to rotate without binding the chain, usually utilizing a bearing in a ball and socket type arrangement. 
   Optionally, a forklift may be used in conjunction with a bag-hanging frame, which engages the bag  24 . The bag suspends from the bag hanging fame and is moved into position with the forklift. The bag-hanging frame engages the main frame assembly. The bag-hanging frame typically engages the top of the main frame assembly and sets upon the four corners of the assembly. There are typically stacking pads on the top four corners of the main frame assembly that position the bag and the bag hanging assembly in the proper discharging position. 
   As shown in  FIG. 4 , the material container transport assembly  18  of the present invention is typically engaged to the hoist  16  by placing the hook  36  in the eyelet portion  38  of the material container transport assembly  18 . The material container transport assembly  18  typically includes a central hub portion  40 , four material container support members  42  engaged to the central hub portion via weld, extending at an upward angle of from about three degrees to about seven degrees, but, most typically about five degrees. The support members  42  typically are spaced at about 90 degree angles from one another (see Angle A in  FIG. 4 ). Each of the material container support members  42  also typically include at least one outwardly extending bag loop retention member, which are typically L-shaped bent steel rods engaged to the support members via a weld or a nut and bolt type arrangement. In the preferred embodiment, there are three L-shaped outwardly extending bag loop support retention members  44  on each material container support member  42  to allow the transport assembly to easily accommodate material bags of various sizes. 
   Additionally, each material container support members  42  typically include an inwardly extending L-shaped bag loop retention member  46  engaged at or near the non-hub engaging end of the material container support members  42 . These L-shaped inwardly extending bag retention members, while not necessary, assist in preventing the loops of the bag/container from falling off the ends of the material container support members when the bag is placed on the ground for removal from the material container transport assembly. Without the L-shaped inwardly extending bag loop retention members, the bag loops could unintentionally disengage from the material container support members of the transport assembly when the bag container is no longer held in position by gravity. The inwardly extending L-shaped bag loop retention members may be of any suitable height, but typically extend slightly higher than the outwardly extending bag loop retention members. Moreover, the inwardly extending L-shaped bag loop retention members are typically substantially flat bent members, while the outwardly extending bag loop retention members may be any suitable shape, but are typically cylindrical in shape. 
   Significantly, the fact that the material container support members  42  extend from the central hub portions at approximately five degrees accomplishes two significant functions. First, via gravity, the angle forces the loops of the bag containers into engagement with the L-shaped outwardly extending bag loop retention members  44  when the bag container is hoisted off of the ground, thereby providing safety benefits during such procedures. Secondly, this construction allows the distance from the bottom of the hoist hook  36  to the top of the bag loops  48  to be optimally minimized from zero inches to about 1½ inches. This allows manufacturers to install the entire bulk bag discharge assembly  10  in facilities with lower ceilings than were previously possible. 
   The bulk bag discharge assembly  10  also typically includes at least two independently driven pneumatic impactors  22  ( FIG. 5 ), which are typically mounted to the main frame assembly  12  using a metal bracket  50  and a nut and bolt type arrangement  52  in spaced adjustment apertures  54  of the metal bracket  50 . The spaced apart adjustment apertures  54  allow the impactors to be moved into a closer or more distant proximity to the material container/bag  24 , as needed, to accommodate various sized material bags  24 . The actual material container  24  contacting portion of the impactors is typically rounded and typically has a plastic or other soft material, which will not harm the bag container material, which is typically plastic or polyester. The impactors are typically located somewhere near the top ⅔ of the bag material container. The impactors of the present invention provide a force of up to about 1000 pounds on each side of the bag to push the material and collapse the rat-holing or bridging that may occur in the bag. The preferred force applied is between about 350 pounds of force to about 1000 pounds of force, but any desired force may, of course, be utilized. Aligning the impactors in this fashion allows the force to be directly at the center of the bag where most rat-holing occurs. The force is typically horizontal. 
   The impactors are adjustable in force, frequency, and stroke. The force may be adjusted by setting the pressure regulator to the desired setting. The frequency may be adjusted by setting an adjustable timer. The stroke may be adjusted by moving the unit in or out using the spaced adjustment apertures  54 . Also, because the impactors are independent from one another, they can be set to stroke into the bag in an alternating fashion such that the right impactor will stroke in when the left impactor retracts and visa versa. This imparts a rocking motion to the bag  24 , which further assists in collapsing any rat-holing that may occur in the material contained within the bag material container  24 . 
   The bulk bag discharging assembly  10  of the present invention also typically contains at least two, typically independently driven, bag massagers  26 , which are mounted such that they massage the bottom portion, typically the bottom about two feet, of the bag material container  24 . The massagers are typically made of steel tubing and are pneumatically driven. The rounded steel tubing allows the assembly to be easily washed down when required. The pneumatic mechanism  80 , that moves the massagers, as with the impactors, each independently provide a force of up to 1000 pounds on each side of the bag. The massagers  26 , like the impactors  22 , are adjustable in force and in frequency. The force is adjusted by setting the pressure regulator to the desired setting and the frequency is adjusted by setting an adjustable timer. Also, as with the impactors, the massagers can be set to stroke into the bag in alternating fashion. The massager on the right will stroke in, then, as it retracts, the massager on the left will stroke in and visa versa. Alternatively, the massagers and the impactors can be set to stroke in and out simultaneously. 
   Further, because each of the impactors and massagers are typically independently driven, the impactors and massagers may be used in conjunction with one another to prevent bridging and rat-holing by any combination of forces. In particular, operators may find that the right impactor and massager should apply force in alternating fashion with the left impactor and massager such that the bag container rocks back and forth. Also, the operator may find that the impactors and massagers may work together in opposing fashion to rock the top of the bag container in one direction while the bottom of the bag container is massaged in opposite directions by the massagers. Of course, pressure may be applied from all impactors and massagers simultaneously as well. 
   The bulk bag discharge assembly  10  also typically includes a discharge-receiving gate  28  having a material container-receiving aperture  58 , which receives the spout portion  60  of the bag material container  24 . The discharge receiving gate  28  also includes three, typically ultrahigh molecular weight plastic (or other durable material not likely to damage the bag material container) plates, which are typically concavely curved and, in the open position, define the material container receiving aperture  58 . Two of the plates  62 ,  64  are substantially aligned, typically engaged with one another, and define a plate receiving area  90  for receiving the middle plate when the plates are in the closed position. 
   In operation, pneumatic cylinders apply force to the two substantially aligned plates and the middle plate  66  in opposing fashion such that the middle plate  66  is received in the middle plate receiving area  90  and is sandwiched between the substantially aligned plates  62 ,  64  as the plates move toward one another. This action not only pinches the bag material spout portion  60  from two sides, but, due to the concave shape of the plates, also cinches the bag from all around. This action closes the bag&#39;s spout portion and pulls it together such that the operator may easily tie off the bag. Moreover, when closed, the ultrahigh molecular weight (UHMW) plastic guide plates support the weight of the bag for better closure. The discharge-receiving gate of the present invention provides significantly more force than previously allowed by other designs, thereby allowing a user to close off standing columns of materials while previous materials must have been flowing in order to close off the bag material containers. The material need not be flowing in order to close off the material containers using the discharge-receiving gate of the present invention. 
   The bulk bag material discharge assembly  10  also typically includes a circular dust tight spout access chamber  30  having at least two access doors  68 ,  70 . The spout access chamber  30  is typically circular, but may be of any suitable shape. When the spout access chamber  30  is circular, the doors  68 ,  70  are gull wing doors, which open wide, thereby allowing access to nearly ⅔ of the spout access chamber. This allows significantly greater space than previous designs for operators to easily and more ergonomically attach a material container bag to the discharge spout. Better access to the spout also results in a significantly increased ability of the operator to achieve a successful seal between the bag spout portion  60  and the connection spool  72 . The spout access chamber  30  typically has an airtight rubber seal  74  about the perimeter of the access openings. This allows for better dust tight sealing of the access chamber when the doors are closed. The doors  68 ,  70  are typically locked using a clamp  76  (see  FIG. 8 ). Optionally, safety interlocks may be employed such that the discharge-receiving gate  28  and/or the bag container connection system discussed below cannot be moved or otherwise altered when the doors  68 ,  70  are open. 
   Contained within the spout access chamber  30  is a bag container connection system, which includes a pneumatically driven sealing ring that moves from a disengaged position to an engaged position (shown in  FIG. 7 ). A sealing ring  81 , which is typically a closed neoprene seal, is engaged to the bottom portion of the metal, typically steel, pneumatically driven ring  82 . The pneumatic cylinders  83  may be positioned inside or outside, but typically are placed inside the access chamber  30 . The neoprene sealing ring prevents damage to potentially fragile bag container material when it is sealed. In operation, the operator would open the doors of the spout access chamber  30 , place the portion  92  of the bag container  24 , which is below the tie  86  around the connection spool  72  or other outlet device while the bag connection system is in its disengaged state. Once the portion  92  below the tie  86  is positioned over the connection spool  72 , the operator actuates the pneumatically or manually operated clamping mechanism into the engaged position, which seals the bag to the connection spout by clamping the portion  92  between the sealing ring and the connection spout. Optionally, a foot pedal may be used to operate the pneumatics  83  and thereby actuate the bag connection system between the engaged and disengaged position, but great care should be used to avoid personal injury if such a control system is used. 
   Once the bag material is in position and properly sealed, the operator merely unties the bag, closes the doors of the spout access chamber, and the bag is ready to be discharged. When a pneumatically actuated clamp is used in the bag connection system, a constant pressure is applied to the sealing ring. If the bag spout portion should move, stretch, or otherwise change the way that the bag is being clamped, the mechanism responds with equal pressure, thereby maintaining a positive seal. 
   The hoist  16 , impactors  22 , massagers  26 , discharge receiving gate  28 , and the bag container connection system are typically all electronically controlled by the operator utilizing control panel  100 . Optionally, a CPU (central processing unit) may be utilized in the present invention to control and automate these functions or any combination of these functions. 
   As seen in  FIGS. 10–11 , the material discharge assembly of the present invention may also optionally include bag conditioning impactors  104  that are designed to at least partially break up or condition material in bag material container  24 , which may have become hardened during transportation or due to exposure to any number of environmental conditions prior to reaching the ultimate location where the material will be transferred from the material container  24  using the material discharge assembly. For example, if salt were transported in a humid or wet environment, such as on a ship, the salt might harden due to this exposure. The bag conditioning impactors  104  operate to break up or condition the material that has hardened inside the material container, thereby allowing material to be discharged from the material container. Typically, at least one and, more typically, at least two or more hydraulic or pneumatic cylinders  106  with carbon steel conditioning frames  108  are used to apply force to the outside of the bag material container  24 . The force applied and the force required to condition the material typically determines the related cylinder quantity and size. Typically, the bag conditioning impactors provide from about 1,000 lbs. to about 25,000 lbs. of force, but more typically about 16,000 lbs. of force. The bag conditioning impactors, unlike the typical pneumatic impactors  22  that are typically used in the present invention to prevent rat-holing, typically move in unison to impact the bag substantially simultaneously. However, conditioning may also be achieved by impacting the bag material container with one bag conditioning impactor at a time. Furthermore, while  FIGS. 10–11  show two bag conditioning impactors, conceivably, any number of impactors could be used. Typically though, either two or four bag conditioning impactors positioned substantially opposite from one another are used. The carbon steel conditioning frames  108  may be of any suitable shape, but are typically a slightly curved smooth surface to help prevent damage to the bag material container when it is struck with the impactor(s). 
   If hydraulic conditioning impactors are used, the system typically employs a hydraulic pumping unit mounted on the side of the main frame assembly; however, the unit may also be free standing. The hydraulic pumping unit may also include a digital pressure switch to control and adjust unit operation and performance. The hydraulic pumping unit may be housed in an enclosure with a bolt on a louvered door for easy cleaning. If the conditioning impactors are pneumatic, the system may include all controls and other systems required to operate the unit in a similar fashion as the hydraulic unit. 
   Optionally, the bag conditioning impactors may be mounted on a separate bag conditioning frame assembly. Such an assembly would be used alone or in conjunction with the material discharge assembly. 
   Any component or combination of components discussed herein may also be manufactured from stainless steel, which is typically used for corrosion prevention, wash-down, and for food material applications. 
   The above description is considered that of the preferred embodiments only. Modification of the invention will occur to those skilled in the art and to those who make or use the invention. Therefore, it is understood that the embodiments shown in the drawings and described above are merely for illustrative purposes and not intended to limit the scope of the invention, which is defined by the following claims as interpreted according to the principles of patent law, including the doctrine of equivalents.