Abstract:
A device and method for stacking and packaging cylindrical products having variable size. Products are placed on edge and organized to a uniform stack size by means of a product compressing drum. The stack is placed in a trough between a cam operating front lug and a back lug. Once between lugs, the uniformly sized stack maybe packaged into uniform size packages.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
   Not Applicable. 
   STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT 
   Not Applicable. 
   REFERENCE TO A SEQUENCE LISTING, A TABLE OR A COMPUTER PROGRAM LISTING COMPACT DISC APPENDIX 
   Not Applicable. 
   BACKGROUND OF THE INVENTION 
   1. Field of the Invention 
   The present invention relates to an apparatus and method for stacking multiple products that do not have a uniform size. More specifically, the apparatus and method stacks products of varying horizontal size utilizing a design that allows for packaging objects of varying size into packages of a single standard size. The apparatus and method is fast, efficient and reliable. 
   2. Prior Art 
   Pastries are a multi million dollar a year business in the United States. The manufacture and sale of donuts is especially lucrative. Many companies package their donuts for later sale in grocery stores or super markets. Unfortunately, packaging donuts has proven very problematic. Because donuts and other pastries rise during baking, end products are not uniformly shaped. Automated packaging machinery typically requires products having precise, uniform shapes. This had caused a development of suitable donut packaging machinery to be very problematic. Because they are of varying size and shape, they generally cause packaging machines to become clogged and the donuts to become smashed or malformed. 
   Currently systems that automatically handle products of a fairly uniform shape and size exist. In the food industry, a good example of this type of product is a sandwich cookie. There is a large amount of prior art that deals with the handling of these uniform types of products. Despite numerous attempts, efforts to use these systems with products that have a large variation in size have been a total failure. Because of these failures, these variable size products are loaded into the horizontal wrapper, or other secondary system, by hand. This is very costly and labor intensive. 
   There have been several attempts in the past to develop machines capable of stacking and packaging multiple donuts. 
   U.S. Pat. No. 3,745,740 to Williams discloses a packaging method and apparatus that stacks donuts and other objects having similar shapes. The patent discloses a method of stacking donuts by dropping them into a cylinder. A moving rod then lowers a stack of donuts into a package. The objects are stacked vertically, not horizontally. This patent does not disclose the use of a rotating drum having successive wells in it. 
   U.S. Pat. No. 4,162,870 to Storm discloses a device to horizontally stack donuts and similar products. A lever lifts objects onto their edge and places them in a horizontal stack held in place by lever arm and a piston. It then drops the objects into a package. It does not disclose the use of a rotating drum to package donuts. 
   U.S. Pat. No. 5,480,278 to Morgan discloses a apparatus and method for stacking frozen patties and other objects having similar shape. A conveyor belt moves the patties onto a piston. After a pre-determined number of patties are rested upon the piston, the piston moves upward to a horizontal platform where they are pushed off the piston. This process is then repeated. The frozen patties are stacked vertically, not horizontally. Furthermore, the stacking action is not continuous. When the piston moves up to the horizontal platform. The stacking action must stop, requiring a discontinuous, slower process. This patent does not disclose the use of a rotating drum to stack objects having variable sizes. 
   U.S. Pat. No. 5,809,745 to Reinert discloses another method for vertically stacking frozen patties and similar objects. This invention uses a rotating cam to lift objects to the bottom of a stack. The objects are vertically stacked and are not on edge. Stacking from the bottom up, as shown in this patent is not suitable for soft objects such as donuts and pastries. Such stacking action would result in the crushing of the product. Furthermore, the patent does not disclose a rotating drum for packaging donuts. 
   U.S. Pat. No. 5,765,337 to Lodewegen et al., discloses another method for vertically stacking cylindrical objects. It provides for vertically not horizontally, stacked items. It also does not disclose the use of a rotating drum to stack variable size objects. 
   U.S. Pat. No. 6,182,814 to Koehler discloses a method of separating a continuous row of on-edge objects into smaller groups. It uses a vacuum and slugs to separate objects that are already on edge. While the objects are horizontally stacked, it does not disclose the use of a rotating drum to accomplish this. 
   U.S. Pat. No. 6,052,969 to Hart et al., discloses a method of stacking cylindrically shaped products. A conveyor belt drops the objects into a stacker thereby placing them on edge. Once the stacking device is full, it transfers the stack to a package. The invention disclosed in this patent is most suitable for hard objects such as frozen patties. Soft objects, such as donuts and pastries, would not stack properly in this device and would probably be significantly damaged. This device does not disclose the use of a rotating drum to package cylindrical objects. 
   U.S. Pat. No. 3,849,969 to Paules discloses a device that individually wraps frozen patties prior to their being stacked on pistons. The patties are stacked vertically, not horizontally. In addition, this device is only suitable for relatively sturdy objects such as frozen patties. Softer objects, such as donuts would be damaged by such a machine. It also does not disclose the use of a rotating drum to package cylindrical objects. 
   U.S. Pat. No. 3,959,951 to Paules discloses an apparatus very similar to the one described in the preceding paragraph. It is suitable only for vertically stacking frozen patties. It would be damaging to softer products. It also does not disclose the use of a rotating drum to package products on edge. 
   U.S. Pat. No. 5,235,796 to Campbell, III et al., discloses a method for stacking and packaging small planar objects such as cookies and crackers. A conveyor belt dumps the objects onto a machine designed to vertically stack them. Once the stacking unit is full, it pivots downward and releases the objects into a package. Arms on the stacking unit rotate outward to allow the stacked objects to be released into the package. The pivoting motion of the stacking unit requires that the packaging be performed in a discontinuous fashion. Stacking must stop when the stacking unit places objects into a package. This patent also does not provide a method of stacking objects of variable size into a standard size package. This patent also does not disclose the use of a rotating drum to provide for continuous packaging. 
   BRIEF SUMMARY OF THE INVENTION 
   The product on edge packaging system takes product delivered on its side in random fashion and turns it on edge, organizes it into product groups and feeds it into a horizontal packaging system, or any other secondary system. The system is unique in its ability to handle product that varies in size greatly with no adjustments or modifications. The system is also ideal for handling soft and delicate items because of the gentle action of the feeding system. 
   The present invention discloses an improved method for stacking and packaging cylindrically shaped, variable size products. A key feature of the invention is a rotating drum used to organize donuts or other variable size, cylindrical objects into a product group of uniform size. As the drum rotates, donuts located in wells in the drum formed into a product group of uniform length. They are rotated into a trough where two lugs hold the horizontally stacked product group in a uniform size. They are then passed through packaging machinery that packages the donuts or other products in packaging of uniform size. 
   Another important feature of the present invention is the manner in which the lugs catch the horizontal product stack. The front and rear lugs operate on separate chain drives. The front lug drive has a cam that causes the front lug to be delayed in entering the trough. The front lug is precisely timed such that it enters the trough and rapidly catches the forward end of the product stack as it exits the rotating drum. One feature of the present invention is the fact that the front lug never enters the drum as the rear lug does. This prevents damage to the product stack and also allows the invention to operate more rapidly. The front lug is timed such that it will not damage the stacked products. One of the difficulties found in the prior art is that lugs in other items utilized to hold a product stacked during packaging will often inadvertently damage one or more of the products. The camming action of the present invention overcomes this deficiency. 
   In the present invention, the products leave the oven or other cooking machinery lying flat. They are conveyed by any number of means to a series of lanes having slots within them. The edges of the products fall within these slots, causing them to turn such that they are on edge. A short conveyor then feeds the products into wells within a rotating drum. As the drum rotates, the products are moved closer together. Once the drum has rotated such that the products are lying within a trough, the product group has been slightly compressed such that the horizontal stack is of a uniform length. The front and rear lugs then grasp the stack and move it down the trough. The drum rotates again and the process is repeated. This process of utilizing a rotating drum greatly increases the speed and efficiency with which donuts and other cylindrical, variable size products may be packaged. Current methods described in prior art patents and methods of packaging by hand are far less efficient. 
   The present invention may be enhanced by adding optional features. These include a photo eye designed to verify that products have fallen into the wells of the drum prior to its rotation. Another option is the use of a placement finger, that insures that a product has fallen into a well in the drum. 
   Any number of suitable conveying means may be used to introduce the cylindrical products of the device. Conveyor belts, rollers and vibrating boards are all suitable methods known to those skilled in the art. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
       FIG. 1  is a top down diagrammatic view of the present invention. 
       FIG. 2  is a diagrammatic side view of the present invention. 
       FIG. 3  is a cross sectional diagrammatic side view of the rotational drum of the present invention. 
       FIG. 4  is a front diagrammatic view of the rotational drum of the present invention. 
       FIG. 5  is a diagrammatic view of the lug system of the present invention. 
       FIG. 6  is a diagrammatic illustration of the camming motion of the lug system. 
       FIG. 7  is a diagrammatic view of the rotational drum of the present invention including additional, optional components. 
   

   DETAILED DESCRIPTION OF THE INVENTION 
   In the present invention, a delivery system presents cylindrically shaped product onto a vibratory pan to spread the product out. The product is then introduced to lanes in which they are turned on edge. They are then fed into product wells in a rotating drum. Working vanes about the drum and tapered side walls facilitate formation of a product group having a uniform length. Leading and trailing lugs then hold and guide the product group into any of a number of packaging systems known in the art. 
     FIG. 1  shows a diagrammatic overview of the present invention. The product  10  is emptied onto vibratory feeding system  12  by any of a variety of delivery systems. Vibratory feeding system  12  spreads the product  10  out to a single level by the natural vibrating action of the pan. The term “product” is used herein to describe cylindrically shaped items having varying size. This action evenly distributes the product  10  to the multiple lanes  14 . The vibratory conveyor  12  uses an oscillating action rather than electromatic shaking. This is important because it provides for a much more gentle feeding action. Many products, such as donuts, are relatively fragile and easily damaged. Use of a gentler, oscillating motion prevents damage of product  10 . However, those skilled in the art will appreciate that the invention may be used for a more durable products in which use of oscillating rather than electromatic action is unnecessary. 
   The product advances down the lanes  14  on the vibratory pan  12 . Further down lanes  14  have slots  16 . Slots  16  are formed by removing one half of the bottom of slots  14 . One side of the product  10  in lanes  14  will fall into slot  16 , causing the product to turn onto its side. Slots  16  are then tapered together so that they form a series of on edge lanes  18 . Conveyor belt  20  moves product  10  through on edge lanes  18  until they reach rotary drum  30 . Conveyor belts  20  facilitate entry of product  10  into rotary drum  30  and are optional. They may be replaced with lanes having a greater slope, thereby allowing gravity to pull the product  10  toward rotary drum  30 . Utilizing slots  16  to turn a product on edge is an established technology well known in the art for turning various products on edge in packaging systems. 
     FIG. 2  illustrates a side view of the present invention. Delivery system  22  delivers product to ramp  24  which subsequently delivers product to vibratory pan  12 . Delivery system  22  may be any other number of delivery system known to those skilled in the art including, but not limited to, vibratory conveyors, bucket conveyors and conveyor belts. Vibratory pan  12  spreads out the product which then falls on its edge in slot  16 . On edge lanes  18  are slightly inclined up to reduce the back pressure of accumulated product. On edge lanes  18  are tapered in order to form a tight group of on edge products to be delivered to drum  30 . 
     FIG. 3  shows a close up side view diagrammatic illustration of rotary drum  30 . Rotary drum  30  has a shield  32  to prevent product  10  from falling out of rotary drum as it rotates. Shield  32  may be placed in either a closed or open position. Servo motor  36  operates conveyor belt  20  which moves product  10  into wells  38  located about the circumference of rotary drum  30 . Conveyor belt  20  provides for smoother motion than an oscillating vibratory pan. This eases the insertion of product  10  into wells  38 . As mentioned above, conveyor belt  20  and servo motor  36  may be replaced with a lane having a steeper slope. This will allow gravity to move product  10  into wells  38 . This may decrease the cost of producing the present invention, as well as reduce the number of moving parts, and therefore the number of things that can break and halt packaging of the product. Rotating drum  30  has several rows of parallel wells in order to form multiple product groups. Servo motor  40  operates belt  43  which causes drum  30  to rotate. Once every well in a parallel row is filled, drum  30  rotates such that an empty well is in position to receive product  10 . Once a row of products in parallel wells reaches interposing region  44  within a trough, leading and trailing lugs will grab the product group and move it to a standard packaging system. 
     FIG. 4  shows a front diagrammatic view of drum  30 . In this particular embodiment, there are six on edge slot lanes  18  feeding rotating drum  30 . Products  10  are placed within product wells  38  that are aligned in parallel rows. Vertical separator vanes  50  extend into the drum  30  in an arc around the drum to maintain product separation and prevent the individual products from falling over. These vanes are important in the function of the drum feeder. By separating the products at the drum load location, they allow the product  10  to fall into a well  38  that is larger in every dimension than the maximum allowable size of the product  10 . At this maximum size, if the products fell into a pocket without separator veins  50 , the resultant large composite area would allow the product to fall over unless all the products were near the maximum allowable size. The resultant multi-piece product group of products is formed by side plates  52  that push the outside products toward the center. As this compression is taking place, separator vanes  50  end in sequence from the outside in. The final center vane is ended only after the product group is fully compressed by tapered side plates  52 . By this action, products  10  are prevented from falling over during the rotating, stack forming process. Tapered side plates  52  are important to the present invention. They organize the products into a product group of uniform length. In order to do this, the product group is pushed together. However, this compression is very slight, as donuts and other products are very fragile. The forces exerted upon the product group by the tapered side panels and the lugs is only great enough to hold them in place. Those skilled in the art will appreciate that the tapered side panels and lugs may be adjusted for different size products to insure that only enough force to hold the products group in place is exerted upon the product group. 
   Without vanes  50 , rotary drum  30  would not be able to handle the range of product sizes it does. This particular embodiment shows a drum designed to form a product group  33  of 6 products  10 . However, those skilled in the art will appreciate that a drum may be shortened or lengthened to accommodate any size product group. For donuts, it is especially desirable to form product groups of 6. For other products, it may be desirable to stack them in groups of 10 or more. 
   Once the products have been formed into product group, they are ready to be removed from the rotary drum and packaged. In order to do this, the product group is rotated into the lug and drum interposing area  44  as shown in  FIG. 5 . A lug system removes the product group and moves it down a trough to a packaging system. The interposing action is critical to the proper functioning of the system. A series of trailing lugs  84  are attached to a trailing lug chain  82  that is driven by motor  86 . This trailing lug  84  pushes the product group from the drum. The leading lug, on the other hand, never passes through any part of the drum pocket. This is possible because leading lugs  88  travel on chain  90  that follows a shorter path than trailing lug chain  82 . Leading lugs  88  are capable of a special camming action causing them to pivot down using stationary cam  92  to prevent interference with the product within interposing position  44 . Because of product variance in size, the products will not fall from the rotary drum with any consistency. Therefore the products must be removed by the positive action provided by trailing lugs  84 . Front lug  88  must always be in front of the multi pack stack to prevent the products from falling over. Simply pivoting the front lug  88  down to clear the drum would be significantly less efficient because the necessary horizontal motion of front lug  88  would prevent trailing lug actuation until the front lug had fully cleared the drum pocket. The combination of vertical and horizontal movement of the front lug  88  provides support for the group during the critical drum rotation. This design also eliminates the need for excessively fast drum rotation. If the leading and trailing lugs followed the same path, the drum would have to rotate at a much higher speed to cycle between the two lugs. This would greatly eliminate the speed at which the drum lug system could operate. The present invention as currently designed allows the drum rotation to take up to one third of the total cycle time between lugs. The result is a system that is limited in speed only by the force of gravity that initially forces the product into the drum product wells. The dual lug system is designed such that the distance between leading lug  88  and trailing lug  84  may be adjusted. 
   The combination of the front lug camming system with a rotating drum provides for a highly efficient method of packaging variable size products on edge. The lugs carry the product groups down trough  94  which leads them to any of a number of packaging systems known to those skilled in the art. The significance of the present invention lies in the ability to form stacked variable size product groups that will fit into uniformly sized packages. 
     FIG. 6  illustrates the mechanism by which front lugs are pushed down by stationary cam  92  and subsequently allowed to pop up directly in front of the product group. Stationary cam  92  engages cam arm  94  that extends downward from leading lug  88 . As leading lug track  90  pulls cam  88  in the direction of directional arrow  96 , leading lug  88  is moved into horizontal position  89  as it remains engaged to stationary cam  92 . Once a leading lug  88  has passed over stationary cam  92 , it immediately springs back into vertical position  91 . This action allows leading lug  88  to spring into the trough and catch the forward end of product group in order to prevent products from falling over. It also allows leading and trailing lugs to retain the length of the product group so that they may be packaged in a uniformly sized package. 
   Various optional features may be added to the present invention to enhance its efficiency. Some of these features are illustrated in  FIG. 7 . Some products  10 , such as chocolate donuts, often stick to one another. This is illustrated in  FIG. 7  by products  10  which are stuck together. This hinders the ability of products  10  to flow into well  38  of drum  30 . This can slow down the machine and require the intervention of human operators. To overcome this difficulty, prodding finger  100  may be added to the design of the invention. Prodding finger  100  is located just above well  38  into which product  10  is to be placed. Prodding finger  100  moves in the direction of directional arrow  102 . This action jars product  10  loose from any other products to which it is stuck. The action of prodding finger  100  is relatively gentle and will not damage even delicate products such as donuts. 
   Also shown in  FIG. 7  is photo eye  110 , aimed at the well into which a product is being placed. When the photo eye detects that a product  10  has been successfully placed into well  38 , it will signal electronically that it is permissible for the drum to rotate and a new well to be filled with product. If no product is detected by the photo eye, the drum will remain un-rotated until it detects a product. A prodding finger and/or photo eye is preferably placed in line with each well of a parallel row of wells along the side of a drum. This will insure that every product group has the same number of products. 
   Photo eye  110  looks into the wells  38  into which the product is being placed and signals the invention to rotate drum  30  once all of the wells are filled. However, for a variety of factors, photo eye  110  may misread whether a well is filled. This is because there are a many moving parts in the vicinity of well  38  and sticky products may move partially into a well, but not remain there. To insure that all product stacks have the appropriate number of products, photo eye  112  may also be added to look into well  39 . For each well  39 , there will be a corresponding photo eye  112 . If any of the photo eyes  112  detect that a well is empty, it will signal the packaging machine of the present invention to stop so that the defective product group may be removed. This prevents the formation of product stacks having fewer than the desired number of products. 
     FIG. 7  also illustrates use of a loading ramp  34  in place of the conveyor belt  20  shown in  FIGS. 1 and 3 . Loading ramp  34  is set at an angle steep enough to allow gravity to exert sufficient force to pull products  10  into wells  38  without damaging them. Those skilled in the art will appreciate that the maximum allowable angle will depend on how sturdy the product is. For example, frozen meat patties could be loaded on a loading ramp have close to 90° while donuts would be loaded at a significantly smaller angle because they are relatively fragile. Loading ramp  34  is attached to the rest of the invention by braces  35 . 
   Whereas, the present invention has been described in relation to the drawings attached hereto, it should be understood that other and further modifications, apart from those shown or suggested herein, may be made within the spirit and scope of this invention.