Abstract:
A method of loading a plurality of food items in multiple layers comprises collecting food items in a staging area in a first plurality of groups, each group having a plurality of food items. The first plurality of groups is displaced substantially simultaneously downwardly into an accumulating and storage area and thereby forming a plurality of first layer group. A second plurality of groups of food items is collected, each of the second plurality of groups having a plurality of food items. The second plurality of groups is displaced substantially simultaneously downwardly into the accumulating and storage area such that the second plurality of groups forms a plurality of second layer groups of food items superposed to the first layer groups, and thereby forming a plurality of two layer-groups. The plurality of two-layer groups of food items are displaced downwardly into a receptacle in a packing area.

Description:
This application is a continuation of application Ser. No. 12/839,820, filed Jul. 20, 2010, now U.S. Pat. No. 8,079,202, which is a continuation of application Ser. No. 12/192,487, filed Aug. 15, 2008, now U.S. Pat. No. 7,757,462, which is a divisional of application Ser. No. 10/730,969, filed Dec. 9, 2003, now abandoned, which claims the benefit of provisional application Ser. No. 60/431,850 filed Dec. 9, 2002. 
    
    
     BACKGROUND 
     The present invention relates to product handling systems and, more particularly, to food product handling systems that receive individual product items, accumulate the items into groups and transfer the groups to a packing receptacle. 
     Systems for packing food product items, and in particular food product items of uniform size and shape, typically consist of a bin or other large container for receiving the individual food items, a device for receiving the food items from the bin and arranging the food items uniformly, and a device for receiving the arranged food items and accumulating the items into groups that are packed in containers. Typical of such systems are systems for packaging frankfurters. 
     Initially, cooked frankfurters are dumped into a large container. That container includes an opening near the bottom and a feed mechanism for depositing the frankfurters on a conveyer system. The conveyer system includes a plurality of belts positioned to receive the frankfurters and align them in an end-to-end orientation in a single line, or multiple lines of single frankfurters. The belts deposit the frankfurters onto a second belt having a plurality of transverse, raised ribs that receive the frankfurters and orient the frankfurters in a parallel orientation. The second belt deposits the frankfurters into a filler head where the frankfurters are collected into groups of several frankfurters (e.g., five frankfurters in a group) and the groups are then deposited into a receptacle having cavities corresponding to the size of the groups. The cavities are lined with plastic material that is used to package the groups of frankfurters for subsequent sale. 
     An example of such a filler head systems is shown in U.S. Pat. No. 5,893,259. That patent shows a filler head that receives cooked frankfurters from an input conveyer and collects the franks in a cage formed by individual rails. The frankfurters are retained in the cage by an index pusher. When a predetermined number of franks have been collected, the index pusher is cycled and conveys the franks onto staging area. The franks in the staging area are retained on spring loaded doors. Groups of franks are arranged in the staging area by an index lug chain. When a predetermined number of groups have been accumulated on the staging area, a ram is cycled to displace the groups downwardly through the spring loaded doors into a receptacle for packing. 
     A disadvantage with such systems is that a ram is required to displace food product items to the receptacle, which adds to the cost and shows the operation of the device. Accordingly, there is a need for a filler head system and method that maximizes the filling of the receptacle. There is also a need for an efficient system and method for rapidly filling a receptacle with multiple layers of food items such as frankfurters. 
     SUMMARY 
     The present invention is multi-layer food item loading system and method that overcomes the disadvantages of prior art systems and methods by providing an efficient and high-speed system and method for multi-layer food item loading into a receptacle. The method of the invention includes the steps of first collecting food items in a first plurality of groups, each of the groups having a plurality of food items, in a staging area, displacing the first plurality of groups substantially simultaneously downwardly into an accumulating and storage area, thereby forming a plurality of first-layer groups of the food items, collecting in the staging area a second plurality of groups of food items, each of the second plurality of groups having a plurality of food items, displacing the second plurality of groups substantially simultaneously downwardly into the accumulating and storage area such that the second plurality of groups forms a plurality of second layer groups of the food items superposed to the plurality of first layer groups of the food items, thereby forming a plurality of two layer groups of food items, and displacing substantially simultaneously the plurality of two layer groups of food items downwardly into a receptacle in a packing area. The advantage of the method of the present invention is that the presence of the accumulating and storage area allows multiple layers of food items to be collected before being displaced into the receptacle in the packing area. This allows higher reliability of product orientation in the receptacle in the packing area and also allows the step of displacing the multi-layer product into the receptacle to be performed substantially simultaneously with the accumulation of subsequent groups of product in the staging area. 
     Another advantage of the present invention is that the method utilizes a gravity feed that allows the groups to fall downwardly from the staging area to the accumulating and storage area by gravity and allows the multi-layer groups of product to be displaced by gravity downwardly into the receptacle. This eliminates the need for rams or other devices of prior art filler heads that add to the expense of the associated filler head and require that the accumulating equipment be stopped to allow cycling of the ram. 
     The system of the present invention includes a pair of sidewardly displaceable rods that support the food items in the staging area and in the accumulating and storage area. When the predetermined number of groups have been accumulated on the staging area by an index lug chain, the rods are cycled by being displaced outwardly to allow the groups of food product items to fall downwardly by gravity to the accumulating and storage area. The groups of food product items remain intact in the accumulating and storage area by dividers that are spaced accordingly. When a predetermined number of layers of food items have been collected in the accumulating and storage area, the rod supports in the accumulating and storage area are displaced sidewardly, allowing the multiple layers of food product to fall downwardly by gravity into the cavities of the receptacle. 
     The system of the invention also includes pairs of tucking flaps that cycle from a substantially vertical orientation to a substantially horizontal or below-horizontal orientation to maintain the desired arrangement of the food product items as they fall downwardly into the packing receptacle. 
     Other objects and advantages of the present invention will be apparent from the following description, the accompanying drawings and the appended claims. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1A  is a schematic drawing of a detail of the loading system of the present invention showing two layers of food product items being displaced simultaneously into the cavity of a receptacle; 
         FIG. 1B  is a side elevation of the schematic detail of  FIG. 1A ; 
         FIG. 1C  shows schematically an alternate embodiment of the present invention in which three layers of food product items are loaded into a receptacle; 
         FIG. 2  is a schematic drawing showing of the present invention showing the action of the support rods of the accumulating and storage area; 
         FIG. 3  is a schematic drawing showing the operation of the tucking flaps of the present invention; 
         FIG. 4  is a schematic side elevation of the filler head of the present invention; 
         FIG. 4A  is a detail of the filler head of  FIG. 4  showing the operation of the tucking flaps and rods in the accumulating and storage area; 
         FIG. 5  is a perspective view of a detail of the filler head of  FIG. 4  showing the operation of the support rods of the staging area and accumulating and storage area; and 
         FIG. 6  is a schematic showing the computer control system of the present invention. 
     
    
    
     DETAILED DESCRIPTION 
     The multi-layer food item loading system of the present invention can accommodate a variety of food items of substantially consistent shape. However, the invention will be described with reference to food items such as frankfurters and the like. The invention is adapted to be retrofitted to a conventional frankfurter loading head or like device such as that shown and described in commonly-owned U.S. Pat. No. 5,893,259, the disclosure of which is incorporated herein by reference. Such loading heads or filler heads are used to receive cooked frankfurters or hot dogs from a conveyer, arrange them in groups and place them in receptacles for packaging. The benefit of the filler head of the present invention over the prior art, such as that shown in the aforementioned patent, is that, as shown schematically in  FIGS. 1A and 1B , it loads multiple layers  10 ,  12  of frankfurters into a cavity  14  of a receptacle  16  substantially simultaneously. Also shown schematically in  FIG. 1C , it is within the scope of the invention to provide a filler head that simultaneously loads three layers  10 ,  12 ,  18  of frankfurters into cavities  14 ′ of receptacle  16 ′. 
     Referring to  FIG. 2 , the filler head of the present invention includes support rods  20 ,  22  that support the frankfurters  24  above the cavity  14  until two layers of frankfurters (not shown) are collected. By allowing the frankfurters to fall by gravity, a ram or other mechanical means of prior art devices is not required to force the frankfurters downwardly into the receptacle  16 , thereby eliminating interruptions caused by retraction of the ram. Sideward displacement of the support rods  20 ,  22  is preferred as it requires less cycle time than doors or flaps. 
     As shown in  FIG. 3 , the filler head of the present invention also includes a pair of tucking flaps  32 ,  34  that are positioned above the receptacle  16 . The tucking flaps  32 ,  34  are elongated panels attached to rods  38 . The rods  38  are rotated about their longitudinal axes by a linear actuator, such as a hydraulic, pneumatic or electric actuator and linkage (not shown). Consequently, the flaps  32 ,  34  rotate between an open position, in which the flaps are oriented substantially vertically, and a closed position, in which the flaps are oriented substantially horizontally (shown in phantom in  FIG. 3 ). Flaps  32 ,  34  are tiered to cycle over layers  10 ,  12  of frankfurters have passed in order to maintain the alignment of product shown. If, for example, a frankfurter  24 ′ (shown in phantom) is out of alignment, when the tucking flaps  32 , 34  pivot they will bring the frankfurter into alignment. 
       FIG. 4  shows a schematic of the filler head of the present invention, generally designated  40 . The filler head  40  is adapted to receive frankfurters, generally designated  42 , from a conventional conveyor system  44 , such as that shown and described in the aforementioned U.S. Pat. No. 5,893,259. That conveyor system  44  includes a sweep arm  45  that collects groups  46  of five franks aided by sprocket stuffier shaft  47 , then performs a complete rotation to move each group  46  to a staging area, generally designated  48 . The staging area  48  consists of pairs of rods  50 ,  51  that are oriented parallel to each other and support groups  52 ,  54 ,  56  of accumulated frankfurters. The rods  50 ,  51  are actuated by a three-bar linkage (see  FIG. 5 ) such that the rods reciprocate in a substantially horizontal direction from a support position (shown in  FIG. 4 ) to a displaced position similar to that shown in  FIG. 4A  for rods  20 ,  22 , in which the rods  50 ,  51  are separated sufficiently to allow the groups  52 ,  54 ,  56  to fall downwardly by gravity. 
     A powered lug chain system  58  includes a chain  60  having a plurality of lugs  62  that are spaced appropriately to collect the groups  46  of frankfurters displaced sidewardly by the sweep arm  44  to the staging area  48 . Although the staging area  48  is shown in  FIG. 4  as handling three discrete groups of frankfurters  52 - 56 , as shown in  FIG. 5 , the staging area  48  includes two rows, each having discrete groups of frankfurters, and the conveyor system  44  feeds two frankfurters at a time to the staging area  48 . 
     An accumulation and storage area  62  is located directly beneath the staging area  48  and includes a plurality of dividers  66  that are fixed to the filler head frame  67  and positioned to correspond to the spacing between the lugs  62  of the lug chain  60  and hence correspond to the width of groups  52 ,  54 ,  56  of frankfurters. The accumulation and storage area  64  also includes retractable rods  20 ,  22  (see  FIGS. 2 ,  4 A and  5 ) to support the collected frankfurters. The tucking flaps  32 ,  34  (See  FIG. 3 ) are positioned below the rods and above the receptacle  16 , located in a packing area  69 . 
     The structure and operation of the support rods of the present invention is shown in  FIG. 5 . Two cylinders  70 ,  72  are positioned in the staging area  48  and are each attached to a clevis  74  that is pivotally connected to link arms  76 ,  78  that, in turn, are pivotally attached to a pair of arms  80 . Arms  80  and a pair arms  82  are each pivotally attached at one end to support bars  84 ,  86  (which are mounted on frame  67 ) and at an opposite end to rods  50 ,  51  that support frankfurters in the staging area  48 . Similarly, in accumulation and storage area  64  cylinders  88 ,  90  each include a clevis  92  that is pivotally attached to link arms  94 ,  96  that, in turn, are attached to a pair of arms  98 . Arms  98  and a pair of arms  100  are pivotally attached at one end to support bars  102 ,  104  (which are mounted on frame  67 ) and at an opposite end to rods  20 ,  22 . 
     Consequently, actuation of cylinders  70 ,  72  draws devises  74  away from the frankfurters, thereby causing link arms  76 ,  78  to cause arms  80 ,  82  to pivot rods  50 ,  51  away from each other to allow frankfurter  106  to fall between the rods downwardly onto rods  20 ,  22  in the accumulation and storage area  64 . Similarly, cylinders  88 ,  90  in the accumulation and storage area  64  are actuated to cause rods  20 ,  22  to move away from each other to allow a multi-layer of frankfurters  108  to fall downwardly into receptacle  16  ( FIG. 4 ). 
     As shown in  FIG. 6 , the filler head  40  (see  FIG. 4 ) preferably is operated by a computer  110 . Computer  110  actuates servo motor M 1  ( 112 ) that drives the input conveyor  44 , servo motor M 2  ( 114 ) that sweep arm  45 , servo motor M 3  ( 116 ) that operates index lug chain  58  and servo motor M 4  ( 118 ) that rotates sprocket stuffer shaft  47 . Computer  110  also actuates solonoid S 1  ( 120 ) that operates cylinders  70 ,  72  in staging area  48 , solonoid S 2  ( 122 ) that controls cylinders  88 ,  90  in accumulation and storage area  64 , and solonoid S 3  ( 124 ) that actuates a cylinder (not shown) that actuates tucking flaps  32 ,  34 . 
     Computer  110  also receives input signals from proximity switch PS 1  ( 126 ) that indicates the initial position of the index lug chain  58 , proximity switch PS 2  ( 128 ) that detects the position of the input conveyer  44 , proximity switch PS 3  ( 130 ) that detects the position of the sweep arm  45  and proximity switch PS 4  ( 132 ) that detects the position of the receptacle  16  in the packing area  69  (see  FIG. 4 ). Alternatively, encoders built into servo motors  112 - 118  and communicating directly with the computer  110  could be used instead of proximity switches  126 - 132 . 
     The operation of the loader head  40  shown in  FIG. 4  is as follows, and is controlled by computer  110 . Frankfurters  42  are delivered by the conveyor  44  where they are collected in groups  46  of five frankfurters each by sweep arm  44 . Sweep arm  44  continuously cycles to displace groups  46  of frankfurters horizontally along rods  50 ,  51  in the staging area  48 , where the groups  46  are displaced by the index lug chain  58  along the rods in groups  52 ,  54 ,  56  of five items, directly above the cavities  14  of the receptacle  16 . Once the groups  52 , 54 ,  56  of frankfurters are positioned as shown in  FIG. 4 , the pairs of rods  50 ,  51  are cycled by computer  110 , during which the cylinders  70 ,  72  displace them sidewardly sufficiently to allow the collected groups  52 ,  54 ,  56  to fall downwardly by gravity to pairs of rods  20 ,  22 . This process takes place at least twice so that two at least two layers  10 ,  12  of groups of frankfurters are collected in the accumulation and storage area  64  between dividers  66 . 
     Once at least two layers  10 ,  12  of groups of frankfurters are collected in the accumulation and storage area  64 , rods  20 ,  22  are displaced sidewardly by cylinders  88 , 90  activated by computer  110 , allowing the two layers  10 ,  12  to fall downwardly substantially simultaneously by gravity to the packing area  69 . At this point in time, tucking flaps,  32 ,  34  are oriented vertically so that the two layers  10 ,  12  of frankfurters of the groups fall downwardly by gravity substantially simultaneously into cavities  14 . Once the frankfurters have fallen below the flaps  32 ,  34 , the flaps are actuated to the closed position (shown in phantom in  FIG. 4A ). This action by the flaps helps to align the frankfurters in substantially parallel orientation by pressing downwardly on any misaligned frankfurters  68  that may be present (shown in phantom). 
     The operation of the filler head  40  is substantially continuous. However the lug chain  58  operates intermittently, pausing momentarily when groups  52 ,  54 ,  56  are positioned as shown in  FIG. 4  in order to allow for the pairs of rods  50 ,  51  to by cycled to allow the group  52 - 56  of frankfurters to fall downwardly into the accumulation and storage area  64 .