Patent Document

This application is a 371 of PCT/US00/19090 filed Jul. 13, 2000, which claims benefit of 60/143,575 filed Jul. 13, 1999, and claims benefit for Ser. No. 60/149,002 filed Aug. 13, 1999. 
    
    
     FIELD OF THE INVENTION 
     The invention relates generally to an assembly for handling separator sheets, and particularly to an assembly that sorts a pile of separator sheets, which are used in stacking multiple layers of products onto pallets, into different piles depending on the characteristics of the individual separator sheets. 
     BACKGROUND OF THE INVENTION 
     Smaller products or articles of production (e.g., beverage containers) are commonly stacked on to pallets for shipping and handling. The products are arranged in horizontal tiers, or layers, on the pallet such that additional layers can be stacked on top of the lower layers. Separator sheets are placed between the layers of products to provide a uniform support surface for each layer of products. The uniform support surface makes adding and removing the top layer of products easier. As the top layers of products are unstacked from the pallet, the separator sheets between each layer are removed and set aside for reuse. 
     Depending on the types of products that are stacked onto the pallet, and the environment where the stacking process takes place, the separator sheets may become dirty and/or damaged. Using a dirty or damaged separator sheet in order to facilitate stacking products into layers on a pallet can result in (i) the products becoming damaged or dirty, (ii) the products being stacked on to the pallet unsafely, and (iii) damage to the palletizing machine that stacks the products on to the pallet. 
     SUMMARY OF THE INVENTION 
     The present invention provides a separator sheet handling assembly that is capable of (i) receiving a stack of separator sheets, (ii) testing the separator sheets, and (iii) sorting the separator sheets into various piles depending on whether each separator sheet is dirty, clean, damaged or undamaged (among other characteristics). 
     The separator sheet handling assembly includes a lifting assembly that is adapted to receive a pallet containing a stack of separator sheets. The lifting assembly positions the stack of separator sheets into a predetermined location where a feed assembly engages a separator sheet positioned at the top of the stack of separator sheets. The feed assembly delivers the top separator sheet to a test assembly where the separator sheet is monitored for a particular characteristic (e.g., cleanliness or structural integrity). The separator sheet is delivered to a first storage assembly if the separator sheet has a particular characteristic, or a second storage assembly if the separator sheet does not include a particular characteristic. 
     Other features and advantages of the invention will become apparent to those skilled in the art upon review of the following detailed description, claims and drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a side view of a separator sheet handling assembly embodying the present invention. 
         FIG. 2  is a top elevation view of the separator sheet handling assembly shown in FIG.  1 . 
         FIG. 3  is an enlarged top elevation view taken in the area  3 — 3  of the separator sheet handling system shown in FIG.  1 . 
         FIG. 4  is a side view of the portion of the sheet handler assembly shown in FIG.  3 . 
         FIG. 5  is a rear view of the portion of the sheet handler assembly shown in FIG.  3 . 
         FIG. 6  is an enlarged side view of the separator sheet handling assembly of  FIG.1  taken from the area  6 — 6  in FIG.  1 . 
         FIG. 7  is an enlarged side view of the separator sheet handling assembly of  FIG. 1  taken from the area  7 — 7  in FIG.  1 . 
     
    
    
     Before one embodiment of the invention is explained in detail, it is to be understood that the invention is not limited in its application to the details of construction and the arrangements of components set forth in the following description or illustrated in the drawings. The invention is capable of other embodiments and of being practiced or being carried out in various ways. Also, it is to be understood that the phraseology and terminology used herein is for the purpose of description and should not be regarded as limiting. 
     DETAILED DESCRIPTION 
     A separator sheet handling assembly  10  embodying the invention is illustrated in  FIGS. 1 and 2 . The illustrated separator sheet handling assembly  10  includes a lift assembly  20 , feed assembly  30 , alignment assembly  40 , test assembly  50 , first storage assembly  60  and second storage assembly  70 . 
     During operation of the separator sheet handling assembly  10 , a pallet  12  having a stack of separator sheets  14  thereon is supplied into the lift assembly  20 . The lift assembly  20  moves the pallet  12  upward until the feed assembly  30  grasps a separator sheet  16  positioned on lop of the stack of separator sheets  14 . The feed assembly  30  transports the separator sheet  16  into the alignment assembly  40 . As the separator sheet  16  passes through the alignment assembly  40 , the separator sheet  16  is maneuvered to a predetermined location for delivery to the test assembly  50 . The test assembly  50  is adapted to test the separator sheet  16  in order to determine if the separator sheet  16  is clean and free from holes, tears or any other damage. The separator sheet  16  is preferably tested (and analyzed) as it is transported through the test assembly  50 , although the movement of the separator sheet  16  might have to either be slowed, or stopped altogether, depending on types of tests that are performed. 
     Depending on the condition of the separator sheet  16 , it is either transported into the first storage assembly  60  or transported over the first storage assembly  60  into the second storage assembly  70 . It should be noted that additional storage assemblies could be added if the test assembly  50  has the capacity to analyze additional characteristics on the separator sheet  16 . As an example, clean and undamaged separator sheets  16  would be transported to the first storage assembly  60 , dirty but undamaged sheets would be transported into the second storage assembly  70  and damaged sheets would be transported into a third storage assembly (not shown). 
     In the assembly illustrated in  FIGS. 1 and 2 , the lift assembly  20  is adapted to receive a pallet  12  that is inserted by a lift truck or other pallet handling device including, but not limited to, a conveyor  21 . Although any conventional lift could be employed without departing from the scope of present invention, the lift assembly  20  is shown as a scissors lift which is powered by a hydraulic cylinder that indexes the pallet  12  upward at designated intervals so that the feed assembly  30  removes the separator sheets  16  one at a time from the top of the stack of separator sheets  14 . 
     Positioned above the lift assembly  20  is a top frame remover assembly  17  (shown in  FIG. 1  only). The top frame remover assembly  17  includes a gripper assembly  18  (shown in the raised position) that is lowered as needed to grab a top frame  19  positioned on top of the stack of separator sheets  14 . The gripper assembly  18  is suspended from, and travels along, horizontal rails  15 . During operation of the separator sheet handling assembly  10 , the gripper assembly  18  is positioned above the lift assembly  20  until a top frame  19  is detected on top of the stack of separator sheets  14 . Operation of the sheet feed assembly  30  is suspended and the gripper assembly  18  lowers until it engages the top frame  19  and grabs it with pneumatically powered grippers (not shown). The gripper assembly  18  then returns to the raised position and moves along guide rails  15  until it is over a frame collection bin  13  where the top frame  19  is released by the grippers to fall into the frame collection bin  13 . As shown in  FIG. 2 , the top frame collection bin  13  is positioned beside lift assembly  20  but it should be understood that it can be positioned in any available position that is adjacent to the lift assembly  20 . 
     The lift assembly  20  also includes an air chamber  25  positioned near the top of the stack of separator sheets  14 . The air chamber  25  moves air through the lift assembly  20  to facilitate removing only the top separator sheet  16  instead of multiple sheets. The sheets in the stack of separator sheets  14  often tend to adhere to the top sheet due to moisture, dirt and/or static among other reasons. 
     In a preferred form of the invention, the lift assembly  20  includes squaring fences (not shown). The squaring fences organize the stack of separator sheets  14  into a neat pile before the uppermost sheet is removed by the feed assembly  30 . The squaring fences can be any configuration commonly known in the art and may continuously, or periodically, square the stack of separator sheets  14  as the lift assembly  20  indexes the pallet upward toward the feed assembly  30 . 
     The feed assembly  30  is shown in detail in  FIGS. 3-5 . The feed assembly  30  is adapted for horizontal movement relative to the lift assembly  20  and the alignment assembly  40 . Horizontal motion is translated to a portion  78  of the feed assembly  30  by a drive  80 . The drive  80  maneuvers a chain  79  in an endless pattern as indicated by arrow A in  FIG. 4. A  bracket  81  is connected to a section of the chain  79  such that the bracket  81  moves along the path of the chain  79 . The bracket  81  is pivotally connected to one end  82  of a support arm  83  such that maneuvering the bracket  81  causes movement of the support arm  83 . An opposite end  84  of the support arm  83  is pivotally connected to a bracket  85  (see  FIG. 3 ) that is connected to a laterally extending support structure  86  of the feed assembly  30 . The pivotal connection between the ends  82 ,  84  of the support arm  83  and the respective brackets  81 ,  85  causes the nonlinear motion of the support arm  83  to be translated to horizontal linear motion of the laterally extending support structure  86 . A pair of support rods  87 A,  87 B extend longitudinally from opposite sides of the laterally extending support structure  86 . The support rods  87 A,  87 B are supported for horizontal movement by bearings  32  positioned on opposite sides of the separator sheet handling assembly  10 . The feed assembly  30  is maneuvered vertically by pneumatic cylinders  34  positioned on opposite sides of the separator sheet handling assembly  10 . 
     The feed assembly  30  includes vacuum fittings  36  that engage the top surface of the separator sheet  16 . A preferred form and arrangement of the vacuum fittings  36  are disclosed in PCT/US97/07520, which is incorporated herein by reference. 
     During operation of the separator sheet handling assembly  10 , the feed assembly  30  moves backward and downward to grasp the separator sheet  16  positioned on the top of the stack of separator sheets  14 . Once the vacuum fittings  36  engage the top surface of the separator sheet  16 , the feed assembly  30  moves upward and forward to position the separator sheet  16  between rotating drive rollers  37 ,  38 . Drive roller  38  drives a first plurality of endless belts  41  and drive roller  37  drives a second plurality of endless belts  39 . The first and second plurality of belts  39 ,  41  contact the upper and lower surface of the separator sheet  16  and deliver the separator sheet  16  into the alignment assembly  40 . 
     The feed assembly  30  includes a pair of brackets  89 A,  89 B that are pivotally connected to support members  90 A,  90 B that are part of separator sheet handling assembly  10 . This pivoted connected allows the feed assembly  30  to be rotated (i.e., raised up) by activating pneumatic cylinders  34  that are positioned on opposite sides of the feed assembly  30 . The ability to raise the feed assembly  30  in this manner permits easy inspection and/or maintenance of the area between the first and second plurality of belts  39 ,  41 , especially when a separator sheet  16  becomes jammed in the feed assembly  30 . 
     The separator sheet  16  is carried through the alignment assembly  40  by the first plurality of belts  41  which are positioned across the width of the separator sheet handling assembly  10 . As the separator sheet  16  travels through the alignment assembly  40 , the separator sheet  16  is maneuvered by guides  42  into a predetermined position. The separator sheet  16  needs to be maneuvered into this predetermined position so that the separator sheet  16  is properly positioned as it enters the test assembly  50 . 
     The plurality of belts  41  also transports the separator sheet  16  through the test assembly  50 . The test assembly  50  uses conventional monitoring devices in order to collect data regarding certain characteristics of each separator sheet  16 . In a preferred form, the test assembly  50  includes a light emitting system  51  that projects light upward toward the separator sheet  16  as the separator sheet  16  passes through the test assembly  40 . The test assembly  50  further includes a sensor  52  that checks to see if any light passes through the separator sheet due to tears or holes in the separator sheet  16 . The test assembly  50  could also perform other tests on the separator sheet  16  that are commonly known in the art, including, but not limited to, checking for load tags and surface contamination (e.g., oil or syrup spots, and footprints). 
     The collected data is supplied to a computer (not shown) or some other decisionmaking entity. The computer then instructs the separator sheet handling assembly  10  to direct the separator sheet  16  into either the first storage assembly  60  or the second storage assembly  70 . 
     The delivery of the separator sheet  16  into either the first storage assembly  60  or the second storage assembly  70  is illustrated in  FIGS. 6 and 7 . Depending on the characteristics of the separator sheet  16 , the computer sends out a signal that directs an actuator  61  to either expand or contract. The actuator  61  is connected to a directing guide  62  that moves up and down as the actuator  61  expands and contracts. In the assembly illustrated in  FIG. 6 , the actuator  61  is contracted such that the directing guide  62  is in a lowered position. When the directing guide  62  is in the lowered position, the separator sheet  16  passes over the directing guide  62  and moves from the plurality of laterally spaced belts  41  onto a separate set of laterally spaced belts  65  that transport the separator sheet  16  to the second storage assembly  70 . 
     If the computer directs the actuator  61  to expand, the directing guide  62  moves into a raised position (see phantom lines in  FIG. 6 ) such that the separator sheet  16  enters the directing guide  62  between an upper bracket  63  and a lower bracket  64 . The separator sheet  16  continues through the directing guide  62  into the first storage assembly  60 . 
     The first storage assembly  60  includes a lifting frame  69  that is capable of supporting a pallet  66  in a predetermined location. The separator sheet  16  enters the first storage assembly  60  and is positioned on top of a pile  67  of previously sorted separator sheets by guides  68 . The lifting frame  69  is maneuvered up and down using chains  100  that are driven by sprockets positioned on opposite sides of a support structure  105 . As the separator sheets  16  continue to stack up on the pallet  66 , the lifting frame  69  is indexed downwardly until a desired number of separator sheets  16  have been stacked on to the pallet  66 . The full pallet  66  may be directed from the first storage assembly  60  via a conveyor (not shown). 
     The situation illustrated in  FIG. 7  occurs when the actuator  61  is retracted and the separator sheet  16  is transported over the directing guide  62  onto the plurality of laterally spaced belts  65 . The plurality of belts  65  transport the separator sheet  16  between an upper bracket  74  and a lower bracket  75  on a receiving guide  71 . The separator sheet  16  passes through the receiving guide  71  and is directed onto a pile of separator sheets  76  by guides  77 . The second storage assembly  70  includes a lifting frame  72  that is adapted to support a pallet  73 . Chains  101  move the lifting frame  72  up and down. Sprockets positioned on opposite sides of a support structure  106  support the chains  101 . The lifting frame  72  indexes downwardly as the separator sheets  16  are stacked onto the pallet  73 . Once the pallet  73  is stacked full of separator sheets, the pallet  73  can either be removed directly or transported via a conveyor (not shown) to another location. 
     The receiving guide  71  is different from the directing guide  62  in that the receiving guide  71  is not adjustable. As stated previously, the separate sheet handling assembly  10  can include additional storage assemblies (not shown). It should be apparent that the separator sheets need to be directed into one of the storage assemblies. The separator sheets will be directed into the storage assembly located on the end of the separator sheet handling assembly  10  if the separator sheet  16  has not been previously directed into another storage assembly. Therefore, a nonadjustable receiving guide  71  should be located before the final storage assembly. 
     In one form of the invention, the storage assemblies  60 ,  70  each include squaring fences (not shown). The squaring fences organize the stack of separator sheets  14  into a neat pile as the sheets  16  are inserted into the respective storage assemblies  60 ,  70 . The squaring fences can be any configuration commonly known in the art and may continuously or periodically square the stacks of separator sheets as the respective lifting frames  69 ,  72  index the pallets  66 ,  73  downward. 
     In another embodiment of present invention the second storage assembly  70  does not include a lifting frame  72 . Instead, the second storage assembly is located adjacent to the frame of separator sheet handling assembly  10  such that sheets  16  which are not delivered to the first storage assembly  60  are delivered off of an end  99  of the separator sheet handling assembly  20  into a receptacle (e.g., a trash bin). 
     Various features of the invention are set forth in the following claims.

Technology Category: 7