Abstract:
A robotic palletizing apparatus includes a conveyor and retractable product support having a support surface controllably extending beyond one end of the conveyor to support the bottom of an article beyond the conveyor end and retracting from the extended position such that the article supported thereon falls substantially flat from its otherwise supported condition.

Description:
This application is a divisional application of U.S. Ser. No. 09/338,200, filed Jun. 22, 1999. 
    
    
     FIELD OF THE INVENTION 
     The invention is in the field of product palletizing. 
     BACKGROUND OF THE INVENTION 
     Immediately after manufacture or before shipping of products, the products are often transferred in boxes, bags, cartons, or the like on conveyor belts. Such packaged, conveyed products must be removed from the conveyor for further packaging and shipping. Frequently, such products must be palletized. 
     Robots and human labor have been long used to remove products from conveyors to place them on pallets on other shipping platforms. The movement of robots and labors is often slower than the speed of which the conveyor is capable and adds complexity and expense to the packaging process. As a result, the conveyor must be slowed or more resources must be added for palletizing. 
     It has long been desired to develop a mechanism to deliver products directly from a conveyor to pallets or other bulk shipping containers. 
     SUMMARY OF THE INVENTION 
     There is provided in this disclosure a robotic palletize apparatus comprising an articulating convey having first and second ends; a pivot located at the first end of the articulating conveyor; a product support located at the second end of the articulating convey; a robot in articulating communication with the articulating conveyor; and a delivery sensor in communication with the product support. The articulating conveyor may further comprise a product orientor. The product orientor may comprise an orienting conveyor. The orienting conveyor may be arched. The product support may comprise a tongue extender. The second end of the articulating conveyor may be angled relative to a gravitational plane. The tongue extender may comprise a tongue and pneumatic cylinder. The apparatus may comprise a product sensor. A feed conveyor may be in proximal communication with the first end of the articulating conveyor. The apparatus may comprise a stop. 
     There is provided also in this disclosure a method of stacking product directly from a conveyor, comprising the steps of conveying a product toward the end of a conveyor; supporting a leading edge of the product as the leading edge exits the conveyor; releasing the leading edge and a following edge of the product with such timing as to cause the product to fall substantially flat onto a platform; and articulating the conveyor, whereby product is stacked in a pattern. The platform may be a pallet and a robot may articulate the conveyor. The supporting step may comprise extending a tongue and the releasing step may comprise retracting the tongue. The method may comprise the step of sensing the location of the product relative to the location of an end of the conveyor. The method may comprise the step of sensing the location of the product relative to the location of the tongue. The method may comprise the step of orienting the product. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a top view of a robotic palletizing apparatus illustrative of the present invention. 
     FIG. 2 is a side view of the robotic palletizing apparatus of FIG. 1 
     FIG. 3 is an end view of the robotic palletizing apparatus of FIG. 1 
     FIG. 4 is a top view of an end effector 
     FIG. 5 is a side view of an end effector 
     FIG. 6 is a top view of an end effector 
     FIG. 7 is a side view of a palletizing conveyor 
     FIG. 8 is a side view of a palletizing conveyor 
     FIG. 9 is a side view of a palletizing conveyor 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     FIGS. 1-7 and  9  are of a palletizing apparatus  1  illustrative of the present invention. Feed conveyor  3  is fixed. It conveys a box  5  toward an articulating conveyor  7 . The articulating conveyor  7  pivots at point  9 . The articulating conveyor  7  includes an end effector  11 . The end effector  11  comprises orienting conveyor  17  and palletizing conveyor  19 . To the end effector  11  is connected a robot  13 . The robot  13  is of any suitable type known to those of ordinary skill in the art, and manipulates with articulating arm  15  the end effector  11  and articulating conveyor about point  9 . The robot  13 , manually or using computer logic, moves articulating arm  15  as required to deliver boxes  5  onto a pallet  21  in a pattern such as  23 . The computer logic may be pre-programed for a particular product size. Product sensor  25  may communicate with the computer logic. Product sensor  25  may be a weight sensor, size sensor, orientation sensor, or any combination thereof. It may sense by any means known to those or ordinary skill in the art, including optical, sonic, tactile means. 
     As box  5  exits articulating conveyor  7  and enters the orienting conveyor  17 , orienting belts  27  travel at different speeds, rotating box  5  so as to give it an orientation suitable for delivery onto pallet  21 . The orienting belts  27  may be driven in logic communication with product sensor  25 . The orienting conveyor  17  may be arched as illustrated in FIG.  5 . Such arching may control traction between the box  5  and the orienting belts  27 , and effect more predictable orientation of box  5 . Any suitable apparatus, in addition to the orienting conveyor, may be used to orient box  5 . 
     After box  5  exits the orienting conveyor  17  and enters the palletizing conveyor  19 , a delivery sensor  29  may detect the approach of box  5  to the exit end of palletizing conveyor  19 . The delivery sensor  29  is in logic communication with a product stabilizer, such as tongue extender  31 . As box  5  exits the palletizing conveyor  19 , tongue extender  31  extends tongue  33  so as to prevent the leading edge of box  5  from falling as it exists the palletizing conveyor  11 . Once a predetermined portion of box  5  is on tongue  33 , tongue  33  rapidly retracts. The rapid retraction causes the leading and following edges of box  5  to begin falling at substantially the same time. Thus, tumbling of the box  5  is reduced. The tongue extender  31  may comprise an entender mechanism of those types known to those of ordinary skill in the art, including, but not limited to, pneumatic cylinders and electric servo motors. 
     In order to facilitate box  5  falling flatly onto pallet  21 , the existing end of palletizing conveyor  19  may be elevated in coordination with the speed of retraction of tongue  33 . The desired degree of elevation is inversely proportional to the speed of retraction of the tongue  33 . Testing has shown that a box  5  will fall flatly onto a pallet if the palleting conveyor is elevated about 5° from the gravitational plane and the tongue retracts in about 0.1 seconds. 
     To facilitate orderly stacking of boxes  5  onto pallet  21 , a first box  5  may be delivered by the end effector  11  to comer  35 . The speed of the belts  37  of palletizing conveyor  19  may be sufficient to throw the box  5  into comer  35 . If such speed is not sufficient to do so, the end effector  11  or the pallet  21  may be manipulated relative to each other to effect desired placement of box  5 . Stop  39  may be positioned to stabilize box  5  as it exits the palletizing conveyor  19  and enters the comer  35 . Once box  5  has been delivered to comer  35 , robot  13  may move end effector  11  so as to deliver subsequent boxes to a comer comprising either the stop  39  or the preceding box  5 . Once a pallet is full, it may be removed and replaced with an empty pallet  43 . Boxes on a pallet, during or after palletizing, may be plastic wrapped for stability using wrapper. The wrapper  41  and stop  39  may be raised and lowered as reflected in FIG. 3 as boxes  5  are stacked higher, or to facilitate removal of loaded pallets from palletizing surface  42 . 
     The advantage of the use of a tongue extender is illustrated by FIGS. 8 and 9. In FIG. 8, without a product stabilizer, the box  5  rotates as it exits a conveyor because the leading edge of box  5  begins to fall before the following edge of box  5  begins to fall. The rotation causes box  5  to create a relatively large gap  44 . In FIG. 9, a stabilized box  5  falls flatly, without substantial rotation, causing box  5  to create a relatively small gap  45 , facilitating tight packing of boxes  5  onto pallet  21 . 
     Those of ordinary skill in the art will recognize with the benefit of this disclosure, that many product stabilizers may be used in conjunction with conveyors to deliver a box flatly from the end of a conveyor. Any product stabilizer that supports the leading edge of a product as it exits the end of a conveyor, and thus enables the product to fall flatly, is suitable. Examples include but are not limited to, tongues and doors.