Abstract:
A system and method of the present invention randomly mixes and palletizes various containers received from a conveyor. A control system received an order in advance to cooperate with an automatic storage and retrieval system to pick the containers, ordered by various customers, and to place them on a second conveyor. A robotic device, such as a robotic arm or a gantry system, selectively picks the containers from the second conveyor and places the containers on a pallet in a mixed fashion. The pallets are delivered to the respective customers.

Description:
RELATED APPLICATIONS 
     This is a non-provisional application that claims priority to a provisional application Ser. No. 60/837,958 filed on Aug. 16, 2006 and incorporated by reference herein in its entirety. 
    
    
     FIELD OF THE INVENTION 
     The present invention relates to a material handling system and a method for handling a multitude of workpieces, and more particularly, relates to a method and apparatus for receiving packages of random size and stacking the packages upon a pallet. 
     BACKGROUND OF THE INVENTION 
     Various order packing methods and systems are currently used in a packaging industry worldwide. Plants and other manufacturing and assembly facilities manually build mixed pallets of multiple SKU&#39;s. This practice results in high labor cost, large floor space, increase of quantity issues, such as damaged products, order accuracy, low pallet density, thereby resulting in an unstable load. It is known to provide methods and apparatuses for stacking individual packages into one or more groups, in order that the groups of packages may be commonly transported to a remote location, such as, for example, distributions centers, supermarkets, gas stations, and the like. 
     The prior art systems and methods do not provide great flexibility and do not readily accommodate different sized packages on a pallet. Moreover, with conventional method and systems, it is difficult to customize orders. The prior art apparatuses, currently used in various plants, typically add cases to pallets by stacking additional cases directly on top of the cases already placed on the pallet, which results columns, spaced from one another, rather than layers of interlocking cases, which are unstable and easily collapsible during transportation to the remote location or between various location and will lead to significant problems associated with safety, material handling system efficiency, significant increases with respect to product delivery time and cost. 
     The prior art is replete with various devices and methods for handling workpieces, such as, for example, devices taught by the U.S. Pat. No. 7,184,855 to Stingel, III et al., U.S. Pat. No. 7,210,894 to Huang, et al.; U.S. Pat. No. 7,210,280 to Cottone et al.; U.S. Pat. No. 7,221,998 to Brust et al.; U.S. Pat. No. 5,175,692 to Mazouz. The U.S. Pat. No. 7,221,998 to Brust et al., for example, teaches a method of building pallets of cases within an automated material handling system wherein the cases are arranged and ordered for placement in a case by case fashion by a robot. The method determines pallet layers to be placed on the pallet and identifies cases for inclusion in the pallet. Using the case dimension information, the cases are classified into at least one group, wherein each group is defined by a height range such that cases classified within a group have a height within the height range associated with that group. The cases of one of the groups can be assigned to locations within a same pallet layer, wherein the pallet layer has an area within a predefined area range. This method is time consuming and do not improve flexibility and speed needed in modern palletizing applications. 
     The U.S. Pat. No. 5,175,692 to Mazouz, for example, teaches a method and apparatus for randomly arriving mixed size and content parcels where a circular “carousel”-type conveyor is used to accept packages and stacks them upon pallets. The method and apparatus use “voxels”, which are of “unit length” to measure the parcels. The “largest common voxel” is determined for modeling purposes. This method is time consuming and do not improve flexibility and speed needed in modern palletizing applications. 
     There is a constant need in the area of a material handling art for an improved method and an automated system, which will randomly mixed containers of various kinds on a pallet in response to an individual order received from a customer. 
     There is also a constant need for an improved system and a method, which results in higher density as the containers are places on the pallet thereby creating a stable pallet. 
     Another constant need in the area of a material handling art is in improved methods and systems that is cost effective thereby providing perfect accuracy in identifying the condition of the containers, which results in elimination of returned goods located in the containers. 
     Although the aforementioned prior art patents present certain advantages over the manual palletizing, needs always exist for improvements over the prior art which provide improved accuracy and efficiency of pallet stacking, which is provided by the present invention. As such, the present invention is directed to solve one or more problems associated with the prior art systems and methods. 
     SUMMARY OF THE INVENTION 
     A system and a method of the present invention present an automated random mixed palletizing application to improve and update currently existing system and methods of manual palletizing to build pallets with containers, i.e. boxes or trays both circular and non-circular cross sections and various dimensions and shapes as ordered by customers. The system includes a controller, a bar code reader/scanner for scanning the labels of the containers to identify SKU and type of the product contained therein. At least one accumulation case conveyor is cooperable with the bar code reader and is designed for accumulating and reading the containers. 
     A vision system measures the length, width, and heights of the containers and also checks if any flaps of the container are open thereby avoiding loose products. A secondary accumulation conveyor accumulates and meters the containers and detects if the flaps of the containers are open. A check weigher of the inventive system checks weight of the containers to determine if any of the containers are broken or defective in any respect. At least one secondary accumulation conveyor (buffer) registers the container per zone and pushes the container to another conveyor, i.e. an assembly conveyor. 
     The assembly conveyor moves the containers selected by the system to be accessible to a robotic device, such as articulating or gantry robot, as required by the customer and based on type of the application, to be pick-up by the four or six axis end of arm robotic device and placed upon a selected pallet. Numerous other elements of the inventive system include and are not limited to a banding and or stretch wrapping system, which bands and or stretch wraps every layer of the containers resting upon the pallet as the pallet is loaded by the robotic device and/or a stretch wrapping device, which wraps every layer of the containers, already band, that rest upon the pallet as the pallet is loaded by the robotic device. In addition, the system is not limited and the integrated software can easily be integrated to the customers ware house management or business data acquisition. For example: send data to a printer and provide a license plate to be placed on the pallet, inventory control and other functional process requirements. 
     As the customer supplies order information, such as quantity and type of the products, this information is stored in a RoboticStar® cell operatively communicated with the control system. An empty pallet is dispensed by a pallet dispenser and transferred through pallet load conveyors or into a automatic palletizing tower. The empty pallet positioned in front of the robot or in case of the tower configuration the empty pallet is elevated upwards and orientated in front of the inventive system ready to receive the containers. The containers may be supplied in a random mode and/or a selected mode once passed the inspection zone, stored in the buffer zone and then pushed through as per the selection onto the conveyance system diverting into several conveyor lanes, i.e. the accumulation case conveyors. The bar code reader, which is mounted on the accumulation case conveyor, reads, checks, and where necessary, rejects non-conformed containers and the containers having the bar code, which the bar code reader failed to read and/or scan. 
     The conforming containers are conveyed to an assembly area. The check system checks the top and bottom of the containers as they are conveyed therethrough. The check system checks the containers for inconsistency of any major flaps detected lower than ¼ by photo eyes. The check system also checks for any inconsistency of top “open” case flaps and case detection thereby identifying leaking and broken containers, by means of weight detection, performed at the check system. All inconsistent containers are rejected to the separate adjacent conveyor and or are divereted to the discharge continues conveyor. 
     The conforming containers are then conveyed toward the buffer indexing case conveyor or assembly conveyor located adjacent the robotic device. The containers are then picked up by the robotic device in either selected or random fashion from the assembly conveyor. The containers are then placed onto the target pallet as per program demand and calculated pattern. Once the order pallet height is reached or order is complete, the pallet is banded and or wrapped and labeled before the pallet leaves to the customer. 
     An advantage of the present invention is to provide a method and a system for an automated random mixed palletizing based on individual order received from a customer integrated to their ware house management system. 
     Another advantage of the present invention is to provide a method and a system that require smaller foot print, increase through put of the palletizing applications. 
     Still another advantage of the present invention is to provide a method of palletizing which results in higher density as the containers are places on the pallet thereby creating a stable pallet. 
     Still another advantage of the present invention is to provide a system and a method of palletizing the containers that is cost effective in inventory tracking with perfect accuracy resulting in elimination of returned goods. 
     Still another advantage of the present invention is to provide a system and a method of palletizing the containers that build pallets per route requirements on to the truck per the truck route. 
     Still another advantage of the present invention is to provide a system and a method of palletizing the containers integrated to automatically collect, store and process valuable data. 
     The collected data is used to provide automatically licensed plates to be placed on the build pallet for tracking, inventory control and other utilization for business management with the integration to the customers ware house management system. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Other advantages of the present invention will be readily appreciated as the same becomes better understood by reference to the following detailed description when considered in connection with the accompanying drawings wherein: 
         FIG. 1  is a general view of an inventive system; 
         FIG. 2  is a partial and a top view of an accumulation conveyor cooperable with an assembly conveyor; 
         FIG. 3  is a side view of  FIG. 2 ; 
         FIG. 4  is a fragmental side view of a robotic device movable from the assembly conveyor to a palletizing location for moving the containers from the assembly conveyor to be palletized at a pallet; 
         FIG. 5  is an environmental view of an alternative embodiment of the system; 
         FIG. 6  is a fragmental perspective view of a checking system incorporated with the accumulating conveyor and adaptable to detect if the container is open, i.e. non-conforming; 
         FIG. 7  is a cross sectional view of the checking system shown in  FIG. 6 ; 
         FIG. 8  is a fragmental view of a gripper of a robotic device; 
         FIGS. 9 through 11  illustrate various embodiments of the pallets with differently palletized containers; and 
         FIGS. 12 and 13  show flow chart of the present invention and detailed sequence of the operational steps of the inventive system. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     Referring to the Figures, wherein like numerals indicate like or corresponding parts, a system of the present invention is generally shown at  10 .  FIGS. 12 and 13  illustrate the flow chart of method of the inventive system  10 . The system  10  presents an automated random mixed palletizing application to improve and update currently existing system and methods of manual palletizing to build pallets with containers  12 , i.e. boxes, both circular and non-circular cross sections and various dimensions and shapes as ordered by customers. Those skilled in the art will appreciate that the container  12  presents a box, a bin, a tray of various kinds without limiting the scope of the present invention. The system  10  is configured to accommodate various palletizing applications such as randomly receiving multiple containers  12  from at least one conveyor and palletizing the containers  12  upon various pallets  14  and selectively picking the containers  12  from one pallet  14  and either placing the containers  12  upon the at least one conveyor and or upon another pallet  14  thereby building a customized pallet with mixed containers  12  of various configurations, dimensions and product contents. 
     The system  10  includes a control system or controller  18 , a bar code reader/scanner  20  for scanning the labels of the containers to identify SKU and type of the product contained therein. The control system or controller  18  and the bar code reader/scanner  20  are shown schematically in  FIG. 1  and are operatively communicated with a pair accumulation case conveyors are generally indicated at  22  and  24  and each defining a respective accumulation path A. The accumulation case conveyors  22  and  24  are roller type conveyors as known to those skilled in the conveyor art. Alternatively, the accumulation case conveyors  22  and  24  may present other modifications such as belt conveyors without limiting the scope of the present invention. The accumulation case conveyors  22  and  24  are mechanically and/or electrically powered without limiting the scope of the present invention. 
     A vision system  26  is operatively communicated with the control system or controller  18  and the bar code reader/scanner  20  and is shown generally in  FIG. 1 .  FIGS. 6 and 7  show a fragmental and cross sectional view of the vision system  26 . The vision system  26  measures length, width, and heights of the containers  12  and also checks if any flaps of the container  12  are open, as shown in phantom in  FIG. 7 , thereby avoiding loose and/or non-conforming products. The vision system  26  included a belt conveyor element  28 , a pair of inclined conveyors  30  spaced from one another to free the bottom of the container  12  and a receiving conveyor element  32 , all of which are integral with the at least one of the accumulation case conveyors  22  and  24 . 
     Alluding to the above, a check weigher  36  of the inventive system  10  is shown generally in  FIG. 1 . The check weigher  36  checks weight of the containers  12  to determine if any of the containers  12  are broken or defective in any respect. As accumulation case conveyors  22  and  24  accumulate and meter the containers  12  and detects if the flaps of the containers  12  are open, one or both conveyors  22  and  24  registers the containers  12  per at least one zone, all generally indicated at  25  in  FIGS. 2  and  3 , and pushes the defective or non-conforming containers  12  to another conveyor  40  as the application requires to be removed therefrom by robotically or manually. 
     The vision system  26 , the control system or controller  18 , the bar code reader/scanner  20 , the vision system  26 , the check weigher  36  will be discussed in details as the description of the present system  10  and the respective method of the automated palletizing of the containers  12  on the pallet  14  will proceed. The accumulation conveyor  22  and  24  moves the containers selected by the system to at least one pick-up load conveyor or an assembly conveyor, generally indicated at  42 , each defining a respective palletizing or assembly path B. Each conveyor  42  extends to a palletizing zone, generally indicated at  44 . The assembly conveyors  42  are roller type conveyors as known to those skilled in the conveyor art. Alternatively, the assembly conveyors  42  may present other modifications such as belt conveyors without limiting the scope of the present invention. The assembly conveyors  42  are mechanically and/or electrically powered without limiting the scope of the present invention. All of the aforementioned components of the present invention are integrated into the system  10  and located within the palletizing zone  44 . Alternatively, any of the aforementioned components may be positioned, based on application and customer&#39;s need, beyond the palletizing zone  44 , without limiting the scope of the present invention. 
     Alluding to the above, the assembly conveyors  42  are at least partially cooperable with the accumulation case conveyors  22  and  24 , respectively. The zones  25 , each zone  25  are further defined by at least one dual zone  50  and at least one triple zone  52  for moving at least two containers  12  from the accumulating conveyor  22  to the assembly conveyor  42 . Each zone  25  is further defined by a frame  54  and a pusher surface  56  cooperable with the frame  54  and movable from an isolated position as the container  12  is receive in the zone  25  to a container engaging position as the pusher surface  56  moves the container  12  from the at least one accumulating conveyor  22  and  24  to the assembly conveyor  42 , as shown by an arrow in  FIG. 1 . The type of the pusher surface  56 , described herein, is not intended to limit the scope of the present invention 
     The assembly conveyor  42  is accessible to a robotic device, such as articulating or gantry robot, generally shown at  60  in  FIG. 1 , as required by the customer and based on type of the application, to be pick-up by the robotic device  60  and placed upon a selected pallet  14 . The containers are handled by a robotic tool shown at  62  in  FIG. 8 . As shown in  FIGS. 4 and 8 , the tool  62  is mounted upon a robotic manipulator  64  having an arm  66  adaptable for multi axial manipulation, such as, for example, an End of Arm Tool (“EOAT”), without limiting the scope of the present invention. In one embodiment, as shown in  FIGS. 1 and 4 , the robotic manipulator  64  is movable in multi-axial fashion between at least two or more locations, such as the pallets  14 , the conveyor  42 , and the like, with the robotic manipulator  64  position therebetween. The robotic manipulator  64  is programmable for compound and multi-axial movement for palletizing the at least one pallet  14  with the containers  12  received from the assembly conveyor  42  in at least one of random and selective mode thereby placing initial container  12  at any point within the pallet  14 , as shown in  FIGS. 1 and 4 , and filling the pallet  14  by building layers and stacks of the containers  12  in a predetermined fashion, as shown in  FIGS. 9 through 11 , as the containers  12  are continuously received in the zones  25  and moved from the zones  25  to the assembly conveyor  42 . 
     Numerous other elements of the inventive system  10  include and are not limited to a banding system, schematically shown at  70  in  FIG. 1 , which bands every layer of the containers  12  resting upon the pallet  14  as the pallet  14  is loaded by the robotic manipulator  64  with the containers  12  and/or a stretch wrapping device, schematically shown at  72  in  FIG. 1 , which wraps every layer of the containers  12 , already band, that rest upon the pallet  14  as the pallet  14  is loaded by the robotic manipulator  64 . 
     As the customer supplies order information, such as quantity and type of the products, this information is stored in a Robotictar® cell  80  operatively communicated with the controller  18 . An empty pallet  14  is dispensed by a pallet dispenser (not shown) and transferred through pallet conveyors into a semi-automatic palletizing tower  74 . The empty pallet  14  is elevated upwardly and is orientated in front of the inventive system  10  ready to receive the containers  12 . The containers may be supplied in a random mode and/or a selected mode through a conveyance system diverting into several conveyor lanes, i.e. the accumulation case and buffer conveyors  22  and  24 . The bar code reader, which is mounted on the accumulation case conveyor, reads, checks, where necessary it rejects non-conformed containers and the containers having the bar code, which the bar code reader failed to read and/or scan. 
     The conforming containers  12  are conveyed to the palletizing zone  44 . The vision system  26  checks the top and lengths, widths height of the containers  12  as they are conveyed therethrough. The vision system  26  checks the containers  12  for inconsistency of any major top flaps detected lower than ¼, as set forth above. Again, as mentioned above, the vision system  26  also checks for any inconsistency of top “open” case flaps and case detection thereby identifying leaking and broken bottles, by means of weight detection, performed at the check weigher  36 . All inconsistent containers  12  are either conveyed or rejected to the adjacent case conveyor  40 . A warning light indicates to operator if the conveyor  40  is full with the inconsistent containers  12  and it will require to be fed the cases onto a buffering indexing conveyor (not shown). The indexing of the reject containers  12  is a manual operation and manually palletized after completion of an order If the rejection conveyor line reaches full capacity, an alarm is given and the cell stops at completion of current pallet to manual processing of reject case. 
     The conforming containers  12  are then conveyed toward the assembly conveyor  42  and a signal is sent the robotic manipulator  64 , such as for example the Allen Bradley PLC for communicating to a coordinator case identity and positioning for picking. The containers  12  are then picked up by the robotic manipulator  64 . Based on application requirement and as each customer desires, the controller  18  includes a software with an algorism with a custom designed program to allow the robotic manipulator  64  to randomly place the picked up container  12  onto the target pallet  14  as per program demand and calculated pattern. Once the order pallet height is reached or order is complete, the separate additional software coordinator sends the picked order to a license printer (not shown) of the controller  18  that passes this information to the labeler (this includes lost/error case information). 
     The banding system or integrated stretch wrap system  70  applies a horizontal band on each completed layer of containers  12 . After the last strap or stretch band is on the pallet the pallet is then lowered by the automatic tower elevator  74 , either provided at the customer&#39;s location or integrated into the system  10 , and then the full mixed pallet is discharged on to the pallet conveyor, which is also integrated into the entire system  10 . The full pallet  14  is then conveyed for the fork lift operator (not shown) to pick up of the full pallet  14 . During this operation the supplied printer prints the license plate with the signal and order given from the controller  18  to the labeler either automatically and/or the fork lift operator then places the label onto the pallet  14  and then picks up the full pallet  14  from the pallet conveyor and moves the full pallet  14  to the designated drop off location. This operation starts over for the next pallet  14 , either same or new order, as per demand. 
     As the vision system  26  device detects length, width, height and weight of the containers  12  and the bar code scanner  20  reads the barcode of each container  12 , which contain Brand Number, Store Order Station Number, Batch Toggle, and the like, the controller  18  performs a consistency check between measured container dimensions and the brand information table, provided by the customer, to prevent damaged and/or incomplete containers  12  from being palletized. The controller  18  detects the end of an order via the Batch Toggle switch, it will block incoming containers  12  of the following order before the buffer entrance. 
     In summary and according to the given current index buffer content, which includes and is not limited to case length, width, height, weight and brand number, the system  10  selects one of the containers  12  and calculates an ideal drop position on the pallet  14 . This target position includes several approach points (3-4 path points) near to the target position in order to avoid robot collisions. Pallet changes (i.e. pallet removals and pallet insertions) are processed as well. If no cases can be placed on the current pallet, the controller is notified to stop palletizing operations and wait until a new pallet has been placed. 
     The vision system, the controller  18 , and the robotic manipulator  64  having the arm  66  are the core module elements of the system  10  and is adaptable to perform the following operation for proper palletizing. The operations include and are not limited to scanning barcode for incoming containers at the store accumulation lane, detecting dimensions of incoming containers  12 , keeping track of the current random index buffer content, passing pick and drop coordinates to robot control, synchronizing the movement of the robotic device and the conveyors  22 ,  24 , and  42 , discharging full pallets to accumulation conveyor and/or moving the tower lift down z-Axis as required and according to maximum Z-Axis value, notifying successful placements and pallet changes, visualizing and storing of cell parameters like pallet dimensions, buffering coordinates, reporting containers  12  that could not be palletized, detect end of order via Batch Toggle switch, handling failure situations, such as, for example, detecting and handle robot collisions inside buffer or above the pallet  14 , detecting and handling lost containers  12  and gripper failures, notifying failure information for appropriate model updating. 
     The incoming sequence of the containers  12  into the random buffer of the system  10  determines the pallet loading result, i.e. filling degree and stability. Therefore, an incoming sequence will improve the pallet loading results. For the final stage of automation a case sequencing module is intended to interact with a system at the customer&#39;s location. Scheduled during any time of the day, the case sequencing module processes the order data of the next day and the current Brand Information Table. In return, an optimal incoming sequence is designated for each order. When the order is finally processed, the system passes this sequence a case sortation system. Finally, the case sortation system diverts the cases to the system  10  in the appropriate sequence. Incoming sequences is handled by Auto Palletizing Unit (APU) of the system  10  as well. 
     The “Order Picking” comes with a standard Human Machine Interface (HMI), which provides all necessary functions to control and run the system  10 . The HMI receives information from the controller  18  indicating the system status (i.e. conveyor running/stopped, faults). The HMI provides manual controls over the conveyors  22 ,  24 ,  40 , and  42  and the existing tower  74 . The bar code scanner  20  sends information as to which SKU is present at the flap detections to the controller  18  so it can determine the parameters for the correct container dimensions and weight. Another bar code scanner reads which container  12  is being presented to the Gantry &amp; Algorism Program to be placed on the pallet  14 . The vision system  26  sends the dimensions of the container  12  that is present at the vision station and the controller  18  determines if the container  12  passes or fails. 
     While the invention has been described with reference to an exemplary embodiment, it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted for elements thereof without departing from the scope of the invention. In addition, many modifications may be made to adapt a particular situation or material to the teachings of the invention without departing from the essential scope thereof. Therefore, it is intended that the invention not be limited to the particular embodiment disclosed as the best mode contemplated for carrying out this invention, but that the invention will include all embodiments falling within the scope of the appended claims.