Patent Publication Number: US-7715615-B2

Title: Separator sheet handling assembly

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     This application claims priority from U.S. Provisional Patent Application No. 60/548,319, entitled “Separator Sheet Handling Assembly”, filed Feb. 27, 2004 by Jeff G. Van Nice, Dennis A. VanderHoeven, and Brian E. Busse. This application is also a continuation-in-part of U.S. patent application Ser. No. 10/030,853, entitled “Separator Sheet Handling Assembly”, filed Jan. 11, 2002 now U.S. Pat. No. 6,910,687, by Jeff G. Van Nice, Dennis A. VanderHoeven, and Brian E. Busse. 
    
    
     BACKGROUND 
     The present invention relates generally to an assembly for handling separator sheets, and more 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. 
     Smaller products or articles of production (e.g., beverage containers) are commonly stacked onto 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 onto the pallet. 
     SUMMARY 
     In one embodiment, the invention provides a test assembly adapted to determine a characteristic of a separator sheet. The test assembly includes a source of light to illuminate at least a portion of a surface of the separator sheet. The test assembly also includes a vision inspection system to record at least one discrete image of the illuminated surface of the separator sheet and apply at least one test to the discrete image to determine the characteristic of the separator sheet. 
     In another embodiment, the invention provides a test assembly adapted to determine a characteristic of a separator sheet that includes a first test sub-assembly and a second test sub-assembly. The first test sub-assembly monitors a first surface of the separator sheet for a first characteristic. The second test sub-assembly is positioned opposite the first test sub-assembly and monitors a second surface opposite the first surface of the separator sheet for a second characteristic. The second test sub-assembly is movable relative to the first test sub-assembly. 
     In another embodiment the invention provides a method of testing a separator sheet for a characteristic. The method includes illuminating at least a portion of a surface of the separator sheet, recording a discrete image of the illuminated surface of the separator sheet, and testing the discrete image to determine the characteristic of the separator sheet wherein the discrete image is subdivided into multiple regions. 
     Other features and advantages of the invention will become apparent to those skilled in the art upon review of the following detailed description 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 view of the separator sheet handling assembly shown in  FIG. 1 . 
         FIG. 3   a  is an enlarged top view of the separator sheet handling system shown in  FIG. 1 , illustrating a lift assembly with a stack of separator sheets, a feed assembly, and a sheet cleaning assembly. 
         FIG. 3   b  is a cross-sectional view through line  3   b - 3   b  of the lift assembly of  FIG. 3   a.    
         FIG. 3   c  is a cross-sectional view through line  3   c - 3   c  of the lift assembly of  FIG. 3   b.    
         FIG. 3   d  is a cross-sectional view through line  3   d - 3   d  of the lift assembly of  FIG. 3   b.    
         FIG. 4  is an enlarged side view of the feed assembly of  FIG. 3   a.    
         FIG. 5  is a cross-sectional view through line  5 - 5  of the feed assembly of  FIG. 4 . 
         FIG. 6  is an enlarged side view of a separator sheet being directed toward a first storage assembly of the separator sheet handling assembly of  FIG. 1 . 
         FIG. 7  is an enlarged side view of a separator sheet being directed toward a second storage assembly of the separator sheet handling assembly of  FIG. 1 . 
         FIG. 8  is an enlarged top view of the lift assembly shown without a stack of separator sheets, the feed assembly, and the sheet cleaning assembly of the separator sheet handling system of  FIG. 1 . 
         FIG. 9  is a side view of the assemblies, particularly the lift assembly, of  FIG. 8 . 
         FIG. 10  is a cross-sectional view through line  10 - 10  of the lift assembly of  FIG. 9 . 
         FIG. 11  is a cross-sectional view through line  11 - 11  of the lift assembly of  FIG. 10 . 
         FIG. 12  is a cross-sectional view through line  12 - 12  of the lift assembly of  FIG. 10 . 
         FIG. 13  is an enlarged end view of a chain drive mechanism for the lift assembly of  FIG. 8 . 
         FIG. 14  is a side view of the chain drive mechanism of  FIG. 13 . 
         FIG. 15  is a top view of the chain drive mechanism of  FIG. 13 . 
         FIG. 16  is an enlarged side view of a chain drive mechanism for the feed assembly of  FIG. 3   a.    
         FIG. 17  is a top view of the chain drive mechanism of  FIG. 16 . 
         FIG. 18  is an end view of the chain drive mechanism of  FIG. 16 . 
         FIG. 19  is an end view of the assemblies, particularly the sheet cleaning assembly, of  FIG. 9 . 
         FIG. 20  is a cross-sectional view through line  20 - 20  of the sheet cleaning assembly of  FIG. 19 . 
         FIG. 21  is a top view of the sheet cleaning assembly of  FIG. 19 . 
         FIG. 22  is an operator-side view of the sheet cleaning assembly of  FIG. 19 . 
         FIG. 23  is a rear view of the sheet cleaning assembly of  FIG. 19 . 
         FIG. 24  is an enlarged side view of a lower portion of a test assembly of the separator sheet handling assembly of  FIG. 1 . 
         FIG. 25  is a top view of the lower portion of the test assembly of  FIG. 24 . 
         FIG. 26  is an enlarged side view of an upper portion of the test assembly of the separator sheet handling assembly of  FIG. 1 . 
         FIG. 27  is a top view of the upper portion of the test assembly of  FIG. 26 . 
         FIG. 28  is an end view of the upper portion of the test assembly of  FIG. 26 . 
         FIG. 29  is a cross-sectional view through line  29 - 29  of the lower portion of the test assembly of  FIG. 24 . 
         FIG. 30  is a cross-sectional view through line  30 - 30  of the lower portion of the test assembly of  FIG. 29 . 
         FIG. 31  is a bottom view of the lower portion of the test assembly of  FIG. 30 . 
         FIG. 32  is a cross-sectional view through line  32 - 32  of the upper portion of the test assembly of  FIG. 28 . 
         FIG. 33  is a top view of the upper portion of the test assembly of  FIG. 32 . 
         FIG. 34  is a cross-sectional view through line  34 - 34  of the upper portion of the test assembly of  FIG. 33 . 
         FIG. 35  is a schematic of the electronic components of a frame detector assembly of  FIG. 3   a  and the test assembly of  FIGS. 24 and 26 . 
         FIG. 36  schematically illustrates the operation of the frame detector assembly. 
         FIG. 37  schematically illustrates the operation of the test assembly. 
     
    
    
     Before any features of the invention are 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 the 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 understood that the phraseology and terminology used herein is for the purpose of description and should not be regarded as limiting. The use of “including”, “having”, and “comprising” and variations thereof herein is meant to encompass the items listed thereafter and equivalents thereof as well as additional items. The use of letters to identify elements of a method or process is simply for identification and is not meant to indicate that the elements should be performed in a particular order. 
     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  14 , a feed assembly  18 , and a sheet cleaning assembly  20 , an alignment assembly  22 , a test assembly  26 , a first storage assembly  30 , and a second storage assembly  34 . A similar separator sheet handling assembly, without the sheet cleaning assembly  20  and the test assembly  26  of the present invention, is shown and described in PCT Publication No. WO 01/04025, the entire contents of which are incorporated herein by reference. 
     During operation of the separator sheet handling assembly  10 , a pallet  38  having a stack of separator sheets  42  thereon is supplied into the lift assembly  14 . The lift assembly  14  moves the pallet  38  upward until the feed assembly  18  grasps a separator sheet  46  positioned on top of the stack of separator sheets  42 . The feed assembly  18  transports the separator sheet  46  (see  FIG. 3   a ) into the alignment assembly  22 . As the separator sheet  46  passes through the alignment assembly  22 , the separator sheet  46  is maneuvered to a predetermined location for delivery to the test assembly  26 . The test assembly  26  is adapted to test the separator sheet  46  in order to determine if the separator sheet  46  is clean and free from holes, tears or any other damage. The separator sheet  46  is preferably tested (and analyzed) as it is transported through the test assembly  26 , although the movement of the separator sheet  46  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  46 , it is either transported into the first storage assembly  30  or transported over the first storage assembly  30  into the second storage assembly  34 . It should be noted that additional storage assemblies could be added if the test assembly  26  has the capacity to analyze additional characteristics on the separator sheet  46 . As an example, clean and undamaged separator sheets  46  would be transported to the first storage assembly  30 , dirty but undamaged sheets would be transported into the second storage assembly  34  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  14  is adapted to receive a pallet  38  that is inserted by a lift truck or other pallet handling device including, but not limited to, a conveyor  50 . Although any conventional lift could be employed without departing from the scope of the present invention, the lift assembly  14  is shown as a chain-driven platform  54  that indexes the pallet  38  upward at designated intervals so that the feed assembly  18  removes the separator sheets  46  one at a time from the top of the stack of separator sheets  42 . Alternatively, the lift assembly  14  may comprise a scissors lift which is powered by a hydraulic cylinder. 
     With reference to  FIGS. 8 and 9 , the platform  54  is shown without a pallet  38  and a stack of separator sheets  42  thereon. The platform  54  incorporates a platform conveyor  58  that is utilized to load the pallets  38  onto the platform from the conveyor  50 .  FIGS. 10 and 11  illustrate a motor  62  and drivetrain  66  utilized to power the platform conveyor  58 . 
     With reference to  FIGS. 10-12  and  13 - 15 , the chain-drive mechanism utilized to raise and lower the platform  54  is shown.  FIGS. 13-15  illustrate a motor  70  drivingly connected to a line shaft  74  (see  FIG. 15 ) via a speed-reducing drivetrain  78 . The line shaft  74  extends across the width of the platform  54  and two drive sprockets  82 ,  86  (see  FIG. 3   a ) are positioned at opposite ends of the line shaft  74 . The respective drive sprockets  82 ,  86  directly drive a first set of endless chains  90 ,  94 , which extend in a vertical direction. 
     With reference to  FIG. 10 , the endless chains  90 ,  94  drive respective two-row sprockets  98 ,  102 . A second set of endless chains  106 ,  110  is driven by the two-row sprockets  98 ,  102  and extend in a horizontal direction toward an operator-side of the assembly  10 . The endless chains  106 ,  110  drive respective two-row sprockets  114 ,  118 , which, in turn, drive a third set of vertically-extending endless chains  122 ,  126 . With reference to  FIG. 12 , the operator-side of the platform  54  is shown fixed to the vertically-extending endless chains  122 ,  126 . Similarly, the back-side of the platform  54  is fixed to the vertically-extending endless chains  90 ,  94 . Such a connection allows the platform  54  to raise and lower with the corresponding movement of the endless chains  90 ,  94 ,  122 ,  126 . Also, as shown in  FIG. 12 , the platform conveyor  58  is supported by the platform  54 , such that the platform conveyor  58  will raise and lower with the platform  54  when the motor  70  is activated. 
     Positioned above the lift assembly  14  is a top frame remover assembly  130  (shown in  FIG. 1  only). The top frame remover assembly  130  includes a gripper assembly  134  (shown in the raised position) that is lowered as needed to grab a top frame  138  (see  FIG. 3   a ) positioned on top of the stack of separator sheets  42 . The gripper assembly  134  is suspended from, and travels along, horizontal rails (not shown). During operation of the separator sheet handling assembly  10 , the gripper assembly  134  is positioned above the lift assembly  14  until a top frame  138  is detected on top of the stack of separator sheets  42 . Operation of the sheet feed assembly  18  is suspended and the gripper assembly  134  lowers until it engages the top frame  138  and grabs it with pneumatically powered grippers (not shown). The gripper assembly  134  then returns to the raised position and moves along rails until it is over a frame collection bin  146  where the top frame  138  is released by the grippers to fall into the frame collection bin  146 . As shown in  FIG. 2 , the top frame collection bin  146  is positioned beside the lift assembly  14  but it should be understood that the collection bin  146  may be positioned in any available position that is adjacent to the lift assembly  14 . 
     The assembly  10  also includes a top frame detector assembly  150  ( FIG. 3   a ) to detect a top frame  138  in the stack of separator sheets  42 . Depending on what is loaded onto the lift assembly  14 , one or more top frames  138  may be mixed within the stack of separator sheets  42 . As such, the top frame detector assembly  150  is operable to differentiate the top frames  138  from the separator sheets  46 . 
     With reference to  FIG. 3   a , the components of the top frame detector assembly  150  are shown positioned above the stack of top frames and separator sheets  42 . The top frame detector assembly  150  includes one or more light sources  154  above the stack of top frames and separator sheets  42  that project light onto the stack of top frames and separator sheets  42 . In the illustrated construction, the light sources  154  comprise high frequency fluorescent lights. As schematically shown in  FIG. 3   a , the light sources  154  are positioned relative to the stack of top frames and separator sheets  42  so to project light onto the upper left corner of the stack of top frames and separator sheets  42 . In another embodiment, a single light source  154  may be used to project light onto the upper left corner of the stack of top frames and separator sheets  42 . Further, the light sources  154  may be positioned accordingly to project light onto any of the corners or edges of the stack of top frames and separator sheets  42 . 
     In the illustrated embodiment, the top frame detector assembly  150  includes a vision inspection system  158  (see  FIG. 35 ), which includes a digital camera  162 , a computer connected to the digital camera, and software loaded on the computer to interface with the camera  162 . In the schematic illustrated in  FIG. 35 , the computer with its software may be integrated with the camera  162  to form a self-contained unit. DVT Sensors, Inc. of Norcross, Ga. provides such a vision inspection system  158  in their line of Legend 500 Series SmartImage Sensors. Like the light sources  154 , the camera  162  is preferably positioned above the stack of top frames and separator sheets  42  to focus on the illuminated corner of the stack of top frames and separator sheets  42 . 
     When a separator sheet  46  is at the very top of the stack of top frames and separator sheets  42 , the light projected by the light sources  154  illuminates the corner of the separator sheet  46 . However, when a top frame  138  is at the very top of the stack of top frames and separator sheets  42 , the light projected by the light sources  154  casts a shadow  166  (see  FIG. 36 ) on the separator sheet  46  immediately below the top frame  138  since the top frame  138  has a significant thickness. The camera  162  is operable to view the contrast of the shadow  166  and the light projected by the light sources  154 , and determines that a top frame  138  is located at the very top of the stack of top frames and separator sheets  42  at that instant. 
     In one embodiment, the camera  162  may interface with a programmable logic controller  170  (“PLC,” see  FIG. 35 ), which may activate the top frame remover assembly  130  to remove the top frame  138  from the stack of top frames and separator sheets  42 . In still another embodiment, an operator may adjust the camera settings and parameters of the vision inspection system  158  with a human-to-machine interface (not shown) or the PLC  170 . 
     In operation of the assembly  10 , the camera  162  may be triggered to capture a digital image of the top-most separator sheet  46  or top frame  138  in the stack of top frames and separator sheets  42 . Any of a number of different events may be involved in triggering the camera  162 . For example, the camera  162  may be triggered once per forward stroke of the feed assembly  18 . 
     After the camera  162  captures the image, the image is analyzed by the vision inspection system software. With reference to  FIG. 37 , the vision inspection system software includes a software program made up of one or more constructs known as “products”  174  to those in the vision inspection industry. Products  174 , in turn, are collections of software elements known as “sensors”  178  that process discrete regions of the image looking for specific visual characteristics. In other words, the sensors  178  are not physical devices, or hardware components. Rather, the sensors  178  are software components of the vision inspection system software that analyze a discrete region of a digital image. Such a discrete region may correspond with, for example, a 4“by 4” area on the separator sheet  46 . Alternatively, the sensors  178  may correspond with regions on the separator sheet  46  of greater or lesser area. 
     The sensors  178  analyze the individual pixels which make up the digital image.  FIG. 36  is a schematic illustration of an exemplary image captured by the camera  162 , at an instant when a top frame  138  is at the very top of the stack of top frames and separator sheets  42 . For example, an “edge sensor”  182  may scan the image to determine if an edge, or any substantially straight and substantially continuous line, exists in the image. As shown in  FIG. 36 , the edge sensor  182  may scan the image and identify the inside edges of the top frame  138 . For the vision inspection system software to accomplish this, the edge sensor  182  may look for a group of pixels (e.g., a row of pixels) having a similar brightness level. If such a group or row is found amongst adjacent pixels of substantially different brightness levels, then the vision inspection system software may conclude that an edge or line exists at the interface of the grouped pixels and the surrounding adjacent pixels. 
     Subsequently, one or more area sensors, or “blob sensors,”  186  may scan the image to determine if any characteristics or defects on the sheet, such as footprints, ink blots, tears, markings, debris, or other “blobs” are present in the image. More particularly, when used in the top frame detector assembly  150 , the blob sensors  186  may identify the brightness contrast between the shadow  166  cast by the top frame  138  and the underlying separator sheet  46  when the top frame  138  and separator sheet  46  are illuminated by the light sources  154 . One or more blob sensors  186  may be aligned with the inside edge(s) of the top frame  138  that was identified by the edge sensor  182  to analyze the individual pixels in the portions of the image outlined by the blob sensors  186 . Each blob sensor  186  may look for a group of pixels (e.g., a “blob” of pixels) having a similar brightness level. Such a group of pixels may be identified amongst other surrounding pixels having substantially different brightness levels compared to the group of pixels. If such a group is found, the vision inspection software may conclude that a “blob” exists in the image. 
     Each blob sensor  186  may also scan its corresponding region of the sheet  46  for areas of differing color or shade from a mean color or shade of the region and compare the size of the areas and the extent of color or shade differentiation to programmed threshold values to determine if the areas qualify as “blobs.” In the application of the top frame detector assembly  150 , such a blob may be indicative of the shadow  166  cast by the top frame  138 . The information may then be relayed from the camera  162  to the PLC  170 , so that the PLC  170  may activate the top frame remover assembly  130  to remove the top frame  138 . 
     The vision inspection system software may also identify the pallet  38  after the stack of top frames and separator sheets  42  has been processed. This may be accomplished in a substantially similar process as described above with reference to the top frames  138 . After the camera  162  captures a digital image of the pallet  38 , the vision inspection system software may apply one or more sensors  178  to identify one or more groups of pixels which substantially contrast with adjacent pixels surrounding the groups. Such groups of pixels may be indicative of particular structural characteristics of the pallet  38  rather than a separator sheet  46 . Also, additional sensors (e.g., proximity sensors, etc.) may be used to detect the position of the platform  54  in the lift assembly  14 . Combining the output of such additional sensors with the analysis of the pallet image, the vision inspection system software may conclude the object in the image is indeed a pallet  38 . Further, the information may then be relayed from the camera  162  to the PLC  170  so that the PLC  170  may activate the platform conveyor  58  to remove the pallet  38  from the platform  54 . 
     The feed assembly  18  is shown in detail in  FIGS. 3   a - 5 . The feed assembly  18  is adapted for horizontal movement relative to the lift assembly  14  and the alignment assembly  22 . Horizontal motion is translated to the feed assembly  18  by a drive  190 . With reference to FIGS.  4  and  16 - 18 , the drive  190  maneuvers a chain  194  in an endless pattern as indicated by arrow A in  FIG. 4 . A bracket  198  is connected to a section of the chain  194  such that the bracket  198  moves along the path of the chain  194 . The bracket  198  is pivotally connected to one end  202  of a support arm  206  such that maneuvering the bracket  198  causes movement of the support arm  206 . An opposite end  210  of the support arm  206  is pivotally connected to a bracket  214  (see  FIG. 4 ) that is connected to a laterally extending support structure  218  of the feed assembly  18 . The pivotal connection between the ends  202 ,  210  of the support arm  206  and the respective brackets  198 ,  214  causes the nonlinear motion of the support arm  206  to be translated to horizontal linear motion of the laterally extending support structure  218 . As shown in  FIG. 3   a , a pair of support rods  222 ,  226  extend longitudinally from opposite sides of the laterally extending support structure  218 . The support rods  222 ,  226  are supported for horizontal movement by bearings  230  positioned on opposite sides of the separator sheet handling assembly  10 . 
     The feed assembly  18  includes vacuum fittings  234  that engage the top surface of the separator sheet  46 . A preferred form and arrangement of the vacuum fittings  234  are disclosed in PCT/US97/07520, which is incorporated herein by reference. The vacuum fittings  234  may be raised and lowered by cylinders  236  to raise and/or lower the separator sheet  46  from the stack of separator sheets  42 . 
     During operation of the separator sheet handling assembly  10 , the feed assembly  18  moves backward and downward to grasp the separator sheet  46  positioned on the top of the stack of separator sheets  42 . With reference to  FIG. 3   a , the feed assembly  18  also includes a plurality of nozzles  238  aimed toward the top of the stack of separator sheets  42 . The nozzles  238  move air through the lift assembly  14  to facilitate removing only the top separator sheet  46  instead of multiple sheets. More particularly, the nozzles  238  discharge bursts or pulses of compressed air. Without pulsing compressed air through the separator sheets  46 , the sheets  46  in the stack of separator sheets  42  often tend to adhere to the top sheet  46  due to moisture, dirt, and/or static, among other reasons. 
     Once the vacuum fittings  234  engage the top surface of the separator sheet  46 , the feed assembly  18  moves upward and forward to position the separator sheet  46  into the sheet cleaning assembly  20  to remove debris from the separator sheet  46 . With reference to  FIGS. 19 ,  20  and  21 , the sheet cleaning assembly  20  is shown receiving a separator sheet  46  from the feed assembly  18 . The sheet cleaning assembly  20  includes one or more pairs of nipped infeed rollers  242   a ,  242   b , at least one infeed roller per nipped pair being driven, to receive the leading edge of the separator sheet  46  from the feed assembly  18 . From the infeed rollers  242   a ,  242   b , the separator sheet  46  is transported between opposing brush rollers  246   a ,  246   b  housed within an enclosure  250 . The brush rollers  246   a ,  246   b  may comprise a plurality of bristles or other brush elements configured to wipe or brush dust and/or other debris from the separator sheet  46 . 
     In the exemplary construction of the sheet cleaning assembly  20 , both of the brush rollers  246   a ,  246   b  may be driven such that both of the upper and lower surfaces of the separator sheet  46  may be brushed. Also, the brush rollers  246   a ,  246   b  may be driven such that the surface speed of the outer periphery of the brush rollers  246   a ,  246   b  is greater than the surface speed of the outer peripheries of the nipped infeed rollers  242   a ,  242   b . By doing this, progress of the leading edge of the separator sheet  46  through the opposed brush rollers  246   a ,  246   b  may not be impeded. 
     The enclosure  250  housing the brush rollers  246   a ,  246   b  is substantially sealed to prevent the escape of dust and/or other debris removed from the separator sheet  46 . The interior of the enclosure  250  may be under a vacuum, such that the dust or other small debris may be evacuated from the enclosure  250  to a designated disposal container. Also, large debris removed from the separator sheet  46  may be too large or heavy to be evacuated from the enclosure  250 . Such large debris may fall to the bottom of the enclosure  250 , where the large debris may accumulate before being collected by opening an access panel  254 . 
     After the leading edge of the separator sheet  46  emerges from the opposed brush rollers  246   a ,  246   b , opposing guides  258 ,  262  help direct the brushed leading edge of the separator sheet  46  toward one or more pairs of nipped outfeed rollers  266   a ,  266   b , at least one outfeed roller per nipped pair being driven. The outfeed rollers  266   a ,  266   b  are similar in size to the infeed rollers  242   a ,  242   b  and are driven at substantially the same rotational speed as the infeed rollers  242   a ,  242   b , such that the surface speed of the outer peripheries of the outfeed rollers  266   a ,  266   b  is substantially the same as the surface speed of the outer peripheries of the infeed rollers  242   a ,  242   b . As a result, since any one separator sheet  46  dwells between the nips of either the infeed rollers  242   a ,  242   b  or the outfeed rollers  266   a ,  266   b  at any given time as the separator sheet  46  is transported through the sheet cleaning assembly  20 , the separator sheet  46  is maintained at substantially the same speed as it is transported through the sheet cleaning assembly  20 . 
     With reference to  FIG. 22 , an upper brush sub-assembly  270  and a lower brush sub-assembly  274  are shown comprising the sheet cleaning assembly  20 . The upper brush sub-assembly  270  is movable away from the lower brush sub-assembly  274  to provide access to the space between the respective brush sub-assemblies  270 ,  274 . In the illustrated construction, the upper brush sub-assembly  270  is shown pivotally movable relative to the lower brush sub-assembly  274 , however, other constructions of the respective brush sub-assemblies  270 ,  274  may be movable with respect to one another in other manners. 
     The upper brush sub-assembly  270  includes the upper infeed rollers  242   a , the upper brush roller  246   a , and the upper outfeed rollers  266   a . The upper brush sub-assembly  270  also includes an upper portion of the enclosure  250  and the upper guide  258 . The upper brush sub-assembly  270  is pivotally supported with respect to the lower brush sub-assembly  274  by an arm  278 . A cylinder  282  (e.g., a pneumatic cylinder) is actuable to cause the upper brush sub-assembly  270  to pivot relative to the lower brush sub-assembly  274 . As shown in  FIG. 22 , the cylinder  282  is pivotally supported on the arm  278  by a bracket  286  fixed to the arm  278 . The cylinder  282  includes an extensible rod  290 , which is connected to the base frame of the assembly  10 , such that extension of the rod  290  causes the arm  278  to pivot upwardly. The pivotal connection between the cylinder  282  and the bracket  286  allows the cylinder  282  to pivot as the rod  290  extends. 
     With continued reference to  FIG. 22 , an auxiliary support  294  for the arm  278  is shown. The auxiliary support  294  includes a plurality of notches  298  on one side thereof to receive a pin  302  fixed to the arm  278 . The auxiliary support  294  may be actuated by a cylinder  306  (e.g., a pneumatic cylinder). The cylinder  306  may include an extensible rod  310  that is biased to an extended position (e.g., by springs), such that if the source of compressed air for the cylinder  306  were removed, the auxiliary support  294  would be pivoted to a position in which the pin  302  would engage one of the plurality of notches  298  in the auxiliary support  294  to provide additional support for the arm  278  and the upper brush sub-assembly  270 . 
     Since the upper and lower brush sub-assemblies  270 ,  274  are separable from one another, a drivetrain  314  configured to accommodate such movement is required. With continued reference to  FIG. 22 , the drivetrain  314  of the lower brush sub-assembly  274  is shown on the operator side of the sheet cleaning assembly  20 . A motor  318  is operable to power multiple chains  320  to drive the lower infeed rollers  242   b , the lower brush roller  246   b , and the lower outfeed rollers  266   b . The motor  318  is fixed to the base frame of the assembly  10 , such that it does not pivot with the upper brush sub-assembly  270 . With reference to  FIG. 23 , a drivetrain  322  of the upper brush sub-assembly  270  is shown on the back side of the sheet cleaning assembly  20 . The drivetrain  322  includes an endless belt  326  that is driven by the lower infeed rollers  242   b , which receive power directly from the motor  318  via the aforementioned chains  320 . When the upper brush sub-assembly  270  is lowered onto the lower brush sub-assembly  274 , a sprocket  330  fixed to the upper brush roller  246   a  drivingly engages the belt  326 . The belt  326  is somewhat flexible, such that it is allowed to deflect and at least partially wrap around the sprocket  330  to provide sufficient friction on the sprocket  330  to drive the upper brush roller  246   a . As shown in  FIGS. 22 and 23 , the upper infeed rollers  242   a  and the upper outfeed rollers  266   a  are not driven. 
     The sheet cleaning assembly  20 , after removing debris from the separator sheet  46 , discharges the separator sheet  46  to the alignment assembly  22 . The separator sheet  46  is carried through the alignment assembly  22  by an endless belt  334  (see  FIG. 24 ) which is positioned across the width of the separator sheet handling assembly  10 . As the separator sheet  46  travels through the alignment assembly  22 , the separator sheet  46  is maneuvered by guides  338  (see  FIG. 2 ) into a predetermined position. The separator sheet  46  needs to be maneuvered into this predetermined position so that the separator sheet  46  is properly positioned as it enters the test assembly  26 . The endless belt  334  also transports the separator sheet  46  to the test assembly  26 . 
     With reference to  FIG. 1 , the test assembly  26  is shown as including a lower test sub-assembly  342  and an upper test sub-assembly  346 . The lower test sub-assembly  342  is operable to monitor or analyze the lower or bottom surface of the separator sheet  46  as it passes through the test assembly  26 , while the upper test sub-assembly  346  is operable to monitor or analyze the upper or top surface of the separator sheet  46  as it passes through the test assembly  26 . Since both the top and bottom surfaces of the separator sheet  46  are analyzed, unobstructed views of the top and bottom surfaces of the separator sheet  46  are required when the sheet  46  passes through the test assembly  26 . As such, the endless belt  334  is not allowed to continue through the test assembly  26 . Rather, the endless belt  334  stops before entering the test assembly  26 , and a plurality of thin linear elements (e.g., piano wires  350 ) span the length of the test assembly  26  to support the separator sheet  46  as it passes through the test assembly  26 . The piano wires  350  terminate at the outlet of the test assembly  26 , where a second endless belt  354  picks up the separator sheet  46  for transport to either of the first or second storage assemblies  30 ,  34 . 
     The lower test sub-assembly  342  is shown in  FIGS. 24 and 25 . With reference to  FIG. 24 , the lower test sub-assembly  342  includes a plurality of light sources  358  to illuminate the bottom surface of the separator sheet  46 . In the illustrated construction, the light sources  358  comprise high frequency fluorescent lights. A first digital camera  362 , like the digital camera  162  utilized in the top frame detector assembly  150 , is housed in an enclosure  366  surrounded by the plurality of light sources  358 . A first translucent background sheet  370  (e.g., Plexiglas™) may be positioned opposite the camera  362 , such that the separator sheet  46  is disposed between the piano wire  350  and the background sheet  370  as the separator sheet  46  passes above the camera  362 . With reference to  FIG. 26 , a plurality of background light sources  374  are positioned above the first translucent background sheet  370  to provide background lighting to the separator sheet  46  as it passes over the first digital camera  362 . The combination of the light sources  358  and the background light sources  374  substantially prevents the formation of shadows over the top and bottom surfaces of the separator sheet  46 . In addition, the background light sources  374  may assist in outlining the edges of the separator sheet  46 . The background sheet  370  may also include a white coating on the surface of the sheet  370  facing the separator sheet  46  to provide a white background for the digital image captured by the camera  362 . Such a white coating on the background sheet  370  provides a stark contrast to the separator sheet  46  during analysis of the image of the lower surface of the separator sheet  46  in identifying the edges of the sheet  46 . 
     The upper test sub-assembly  346  is shown in  FIGS. 26-28 . With reference to  FIG. 26 , the upper test sub-assembly  346  includes a plurality of light sources  378  to illuminate the top surface of the separator sheet  46 . In the illustrated construction, the light sources  378  comprise high frequency fluorescent lights. A second digital camera  382  like the first digital camera  362  is housed in an enclosure  386  surrounded by the plurality of light sources  378 . A second translucent background sheet  390  similar to the first background sheet  370  may be positioned opposite the camera  382 , such that the separator sheet  46  is supported by the piano wire  350 , and the background sheet  390  is positioned below the piano wire  350 . With reference to  FIG. 24 , a plurality of background light sources  394  are positioned below the second translucent background sheet  390  to provide background lighting to the separator sheet  46  as it passes below the second digital camera  382 . The combination of the light sources  378  and the background light sources  394  substantially prevents the formation of shadows over the top and bottom surfaces of the separator sheet  46 . In addition, the background light sources  394  may assist in outlining the edges of the separator sheet  46 . The background sheet  390  may also include a white coating on the surface of the background sheet  390  facing the separator sheet  46  to provide a white background for the digital image captured by the camera  382 . Such a white coating on the background sheet  390  provides a stark contrast to the separator sheet  46  during analysis of the image of the top surface of the separator sheet  46  in identifying the edges of the sheet  46 . 
     With reference to  FIG. 28 , the upper test sub-assembly  346  is pivotally coupled to the lower test sub-assembly  342  for pivotal movement in the direction of arrow B. This allows an operator to access either of the cameras  362 ,  382  or any of the light sources  358 ,  378  and/or background light sources  374 ,  394  for repair and/or replacement. The upper test sub-assembly  346  may be pivoted by a cylinder  398  actuated by a source of compressed air or pressurized fluid. The cylinder  398  includes a housing  402  and an extensible rod  406 . In the illustrated construction, the housing  402  is pivotally coupled to the frame of the test assembly  26 , while the rod  406  is pivotally coupled to a lever arm  410  extending from the upper test sub-assembly  346 . A counterweight  414  is coupled to the lever arm  410  to assist the cylinder  398  in pivoting the upper test sub-assembly  346 . When opening the test assembly  26  (i.e., pivoting the upper test sub-assembly  346  away from the lower test sub-assembly  342 ), the counterweight  414  allows the upper test sub-assembly  346  to be pivoted by the cylinder  398  with minimal effort, compared to the force capacity of the cylinder  398 . Also, when closing the test assembly  26  (i.e., pivoting the upper test sub-assembly  346  toward the lower test sub-assembly  342 ), the counterweight  414  allows the upper test sub-assembly  346  to be pivoted downward at a controlled rate by the cylinder  398 . The combination of the cylinder  398 , lever arm  410 , and counterweight  414  allows the upper test sub-assembly  346  to be pivoted while decreasing the probability of accidental shock or damage to the digital cameras  362 ,  382 . 
     During operation of the assembly  10 , it is difficult to expose the entire top and bottom surfaces of the sheet  46  to the respective cameras  362 ,  382  at one time. Thus, the cameras  362 ,  382  are triggered at fixed sheet travel distance intervals to capture discrete images of a fraction of the top and bottom surfaces of the separator sheet  46 , with as many images being taken at short enough intervals such that the entire surface of the sheet is imaged. With reference to FIG.  24 , a sensor  416  (e.g., a proximity sensor, a light sensor, etc.) may be positioned near the inlet of the test assembly  26  to detect the leading edge of the separator sheet  46 , while another sensor  420  may be utilized to output pulses at fixed intervals of movement of the second endless belt  354 . Alternatively, other sensor arrangements may be utilized to cause the cameras  362 ,  382  to trigger at fixed intervals of sheet motion. The sensors  416 ,  420  may be electrically connected to the PLC  170 , which, in turn, may trigger the cameras  362 ,  382 . 
     The camera  362  may be triggered accordingly such that it captures multiple discrete images of the bottom surface of the separator sheet  46 . For example, as the separator sheet  46  enters the test assembly  26 , the first or lower camera  362  may be triggered at fixed distance intervals to capture four discrete images of different portions of the bottom surface of the separator sheet  46 . After each image is captured by the camera  362 , the image may be analyzed by the vision inspection system software. 
     Likewise, the camera  382  may be triggered accordingly such that it captures multiple discrete images of the top surface of the separator sheet  46 . For example, as the separator sheet  46  enters the test assembly  26 , the second or upper  382  may be triggered at fixed distance intervals to capture four discrete images of different portions of the top surface of the separator sheet  46 . After each image is captured by the camera  382 , the image may be analyzed by the vision inspection system software. Alternatively, the cameras  362 ,  382  may be configured to capture a different number of images of the respective bottom and top surfaces of the separator sheet  46 . In addition, an operator may adjust the settings and parameters of the cameras with a human-to-machine interface (not shown) or the PLC  170 . 
     Each image may be tested with a different product  174  that has sensors  178  configured appropriately for the nature of the image captured. With reference to  FIG. 37 , there are three different types of images captured by each camera  362 ,  382  as the separator sheet  46  passes through the test assembly  26 . The first image  418  includes the leading edge portion of the separator sheet  46 . The second image  422  and the third image  426  look substantially identical, and each show a band of the middle portion of the sheet  46 , with the leading and trailing edges out of view. The last and fourth image  430  shows the trailing edge portion of the sheet  46 . The sensor layouts within each product  174  are tailored for the type of image seen (e.g., leading edge portion, middle portion, and trailing edge portion). Separate products  174  may be utilized to test the second and third images  422 ,  426  captured even though the sensor layouts on the images  422 ,  426  are substantially identical. This may be done so that the quantitative sensitivity and result data for the second and third images  422 ,  426  can be differentiated. 
     In the illustrated embodiment, the products  174  include one or more edge sensors  182  to scan the images  418 ,  422 ,  426 ,  430  to determine if any edge characteristics or edge defects exist on a top or bottom surface of the sheet  46 . Such edge characteristics or edge defects may include, for example, wrinkled or torn edges or corners. For an edge sensor  182  to identify such edge defects, each edge sensor  182  may look for a group of pixels (e.g., a row of pixels) having a similar brightness level. If such a group or row is found amongst adjacent pixels of substantially different brightness levels, then the vision inspection system software may conclude that an edge or line exists at the interface of the grouped pixels and the surrounding adjacent pixels. After identifying one or more edges of the sheet  46 , the edge sensor  182  may interface with a “script sensor”, which is described in more detail below, to determine the quality of the edge. 
     In the illustrated embodiment, the products  174  also include one or more blob sensors  186  to scan the images  418 ,  422 ,  426 ,  430  to determine if any characteristics or defects exist on a top or bottom surface of the sheet  46 . Such characteristics or defects may include, for example, footprints, ink blots, tears, holes, markings, debris, or other surface contaminants present in the images  418 ,  422 ,  426 ,  430 . Each blob sensor  186  may look for a group of pixels (e.g., a “blob” of pixels) having a similar brightness level. Such a group of pixels may be identified amongst other surrounding pixels having substantially different brightness levels compared to the group of pixels. If such a group is found, the vision inspection software may conclude that a “blob” exists in the image  418 ,  422 ,  426 , or  430 . Each blob sensor  186  may also scan its corresponding region of the sheet  46  for areas of differing color or shade from a mean color or shade of the region and compare the size of the areas and the extent of color or shade differentiation to programmed threshold values to determine if the areas qualify as “blobs,” or defects in the sheet  46 . Such a “blob” may be indicative of footprints, ink blots, tears, holes, markings, debris, or other surface contaminants present on the corresponding separator sheet  46 . 
     Each sensor  178  (e.g., an edge sensor  182  or a blob sensor  186 ) outputs a pass/fail result, and may also output one or more quantitative results appropriate to the type of test it performs. The pass/fail result for a given sensor  178  is typically the comparison of one or more of these quantitative results to threshold values configured into the individual sensor  178  by the PLC  170 . For example, a blob sensor  186  may include threshold values relating to intensity, contrast, blob size (i.e., how many pixels define the “blob”), and/or blob count (i.e., the number of “blobs” determined by the blob sensor  186 ). If a threshold value is exceeded, the blob sensor  186  would output a “fail” result to the PLC  170 , indicating that the corresponding portion of the sheet  46  analyzed by the blob sensor  186  contains a defect characteristic, such as an ink spot, associated with it. Further, if any sensor  178  in any product  174  of either side of the sheet  46  outputs a “fail” result, the entire sheet  46  would fail visual inspection and would be routed to the second storage assembly  34 . 
     In a further embodiment, each blob sensor  186  performs multiple scans of its corresponding region of the sheet  46  with differing threshold values of size of area and extend of differing color or shade from a mean color or shade of the region to determine if the areas are defects in the separator sheet. In still another embodiment, the sensors for each region of the sheet  46  measures mean color or shade of each region, minimum color or shade of each region, and maximum color or shade of each region, whereby the vision inspection system compares these values with the at least one threshold value for the region to determine if there defects in the separator sheet. 
     As previously mentioned, there also exists another type of sensor  178  known as a “script sensor” that operates similarly in concept to a Visual Basic script in Microsoft Office™ and other software products. The script sensor is capable of reading and/or writing individual sensor result values and/or threshold/sensitivity settings. The script sensor may also dictate the pass/fail result for the product  174  that is the result of a more complex calculation of individual sensor results than a simple logical and summation of all visual sensors  178 . For example, quality values for the edges of the sheet  46  and/or quality values for the corners of the sheet  46  may be determined using script sensors in combination with edge sensors  182 . Edge quality of the sheet  46  may be determined using a “sum” threshold value and/or a “peak” threshold value. A sheet  46  may fail as the result of the sum threshold value being exceeded, or the sheet  46  having many small edge defects, such as small tears, holes, or wrinkles. A sheet  46  may also fail as the result of the peak threshold value being exceeded, or the sheet  46  having one large edge defect, such as a large tear or wrinkle. 
     The pass/fail result of each sensor  178  in each product  174  on both sides (top and bottom) of the sheet  46  is compiled by the vision inspection system software, and a single “pass/fail” result for the sheet  46  is output to the PLC  170 . For a sheet  46  to fail, only one of the sensors  178  needs to output a “fail” result. The PLC  170  may then use the pass/fail information to determine where to route the sheet  46 . 
     An operator may provide input to the PLC  170  to control or adjust the sensitivity of the cameras  362 ,  382  to detect characteristics. More particularly, the PLC  170  may write one or more tables of numeric data into the cameras  362 ,  382 , such that the tables of data are transferred into individual sensors  178  by the script sensors to control individual sensor sensitivity. This may be desirable to focus the analysis of the separator sheet  46  to one particular portion of the sheet  46 . For example, the sensitivity of one particular sensor  178  corresponding with a region of the sheet to have known markings may be decreased by the operator&#39;s input, while the sensitivity of an adjacent sensor  178  corresponding with a region of the sheet that has no known markings may be increased by the operator&#39;s input. That is, the sensitivity of the sensors  178  in each region is controlled separately from the sensitivity in other regions. In addition, the sensitivity of any of the sensors  178  may be decreased a substantial amount by the operator via the PLC  170  to effectively deactivate the sensors  178  to allow sheets  46  with known markings (e.g., bar codes, printed characters, etc.) in known regions on the sheet  46  to pass visual inspection. 
     Another script sensor may gather the results (i.e., a pass or fail result) of the individual sensors  178  and transfer those results into another table that may be referenced by the PLC  170  to tabulate sheet data, which may be referenced by an operator. Each product  174  may read and/or write to different areas of the tables so that a numeric “composite” of the entire sheet  46  may be generated using the four discrete images  418 ,  422 ,  426 ,  430 . 
     The PLC  170  may analyze the images  418 ,  422 ,  426 ,  430  for patterns that are part of a larger pattern purposefully printed on the surface of the sheet  46 . If the printed pattern is recognized by the PLC  170 , the sheet  46  may pass visual inspection. The PLC  170  may also recognize differing orientations of the same asymmetric printed pattern on the sheet  46 . Such a scenario may occur when identical sheets  46  are not consistently oriented with respect to each other before entering the test assembly  26 , such as the sheet  46  is rotated 180° or is turned over. 
     The PLC  170  may be adaptive to variations in the position of such printed patterns to reject a particular sheet  46  on the basis of defects found outside of the detected location of the printed pattern but within the area where the printed pattern can be found on other sheets  46  that are not consistently oriented with respect to the particular sheet  46 . 
     The PLC  170  may also apply multiple pattern analyses to the images  418 ,  422 ,  426 ,  430  such that multiple printed patterns on the sheets  46  can be recognized to allow the sheets  46  to pass visual inspection. To accomplish this, a simple pattern recognition algorithm may be applied to a pseudo-image that has the resolution of the number of discrete regions into which the sheet  46  will be divided (i.e., each discrete region equals one pixel of resolution). The majority of the printed patterns on the sheets  46  will be configured as color bands or stripes that extend the entire length or width of the sheet  46 . There is little that can happen to the sheet  46  that will create a defect that would emulate this “banding” without creating other detectable defects outside the pattern. 
     If, for example, the pseudo-image of the sheet  46  is divided into 20 discrete regions along the width of the sheet  46  and  30  discrete regions along the length of the sheet  46  for a total of 600 total discrete regions. Such an example is analogous to a spreadsheet of 20×30 cells. A perfect sheet  46  has all empty cells, and a value (e.g., a “fail” result) in any cell indicates a bad sheet  46 , unless all of the cells in a particular row or column also have values. The pattern recognition algorithm may define ranges of row or column values that it will accept to allow a sheet  46  to pass visual inspection. In addition, the operator may purposefully select particular cells that would be ignored during analysis. 
     The test assembly  26  may also perform other tests on the separator sheet  46  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). Further, the test assembly  26  may be configured to measure sheet characteristics other than defect characteristics, such as thickness, base color, material (e.g., plastic, craft paper, etc.), and/or moisture content. The test assembly  26  may be configured to measure and recognize color bands, or stripes, printed across the length or width of a surface of the separator sheet  46 . Such color bands or stripes may be indicative of the thickness of the separator sheet  46  or some other information or characteristic relating to the sheet  46 . Based on the results of the analysis performed by the test assembly  26 , the sheets  46  may be sorted into an appropriate destination bin or storage assembly. 
     From the test assembly  26 , the separator sheet  46  is delivered either to the first storage assembly  30  or the second storage assembly  34  by the second endless belt  354 , illustrated in  FIGS. 6 and 7 . However, the sheet  46  may not be required to be transported to either of the first or second storage assemblies  30 ,  34  after passing through the test assembly  26 . Rather, depending on the result of visual inspection of the sheet  46  by the test assembly  26 , the sheet may be routed to other machines for additional processing. 
     Depending on the characteristics of the separator sheet  46  (i.e., whether the sheet  46  “passes” or “fails” visual inspection), the PLC  170  sends out a signal that directs an actuator  434  to either expand or contract. The actuator  434  is connected to a directing guide  438  that moves up and down as the actuator  434  expands and contracts. In the assembly illustrated in  FIG. 6 , the actuator  434  is contracted such that the directing guide  438  is in a lowered position. When the directing guide  438  is in the lowered position, the separator sheet  46  passes over the directing guide  438  and moves from the second endless belt  354  onto a third endless belt  442  that transports the separator sheet  46  to the second storage assembly  34 . 
     If the PLC  170  directs the actuator  434  to expand, the directing guide  438  moves into a raised position (see phantom lines in  FIG. 6 ) such that the separator sheet  46  enters the directing guide  438  between an upper bracket  446  and a lower bracket  450 . The separator sheet  46  continues through the directing guide  438  into the first storage assembly  30 . 
     The first storage assembly  30  includes a lifting frame  454  (see  FIG. 1 ) that is capable of supporting a pallet  458  (see  FIG. 6 ) in a predetermined location. The separator sheet  46  enters the first storage assembly  30  and is positioned on top of a pile  462  of previously sorted separator sheets by guides  466 . The lifting frame  454  is maneuvered up and down using chains  470  that are driven by sprockets positioned on opposite sides of a support structure  474  ( FIG. 1 ). As the separator sheets  46  continue to stack up on the pallet  458 , the lifting frame  454  is indexed downwardly until a desired number of separator sheets  46  have been stacked on to the pallet  458 . The full pallet  458  may be directed from the first storage assembly  30  via a conveyor (not shown). 
     The situation illustrated in  FIG. 7  occurs when the actuator  434  is retracted and the separator sheet  46  is transported over the directing guide  438  onto the third endless belt  442 . The third endless belt  442  transports the separator sheet  46  between an upper bracket  478  and a lower bracket  482  on a receiving guide  486 . The separator sheet  46  passes through the receiving guide  486  and is directed onto a pile of separator sheets  490  by guides  494 . The second storage assembly  34  includes a lifting frame  498  that is adapted to support a pallet  502 . Chains  506  move the lifting frame  498  up and down. Sprockets positioned on opposite sides of a support structure  510  support the chains  506 . The lifting frame  498  indexes downwardly as the separator sheets  46  are stacked onto the pallet  502 . Once the pallet  502  is stacked full of separator sheets  46 , the pallet  502  can either be removed directly or transported via a conveyor (not shown) to another location. 
     The receiving guide  486  is different from the directing guide  438  in that the receiving guide  486  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  46  need to be directed into one of the storage assemblies  30 ,  34 . The separator sheets  46  will be directed into the storage assembly  34  located on the end of the separator sheet handling assembly  10  if the separator sheet  46  has not been previously directed into another storage assembly  30 . Therefore, a non-adjustable receiving guide  486  should be located before the final storage assembly  34 . 
     In one embodiment, the separator sheet handling assembly  10  includes additional storage assemblies (beyond the first and second storage assemblies  30  and  34 ) for receiving separator sheets  46 . For example, clean and undamaged separator sheets  46  are transported to the first storage assembly  30 , dirty but undamaged sheets  46  would be transported into the second storage assembly  34  and damaged sheets would be transported into a third storage assembly (not shown). 
     In one form of the invention, the storage assemblies  30 ,  34  each include squaring fences (not shown). The squaring fences organize the stack of separator sheets  42  into a neat pile as the sheets  46  are inserted into the respective storage assemblies  30 ,  34 . 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  454 ,  498  index the pallets  458 ,  502  downward. 
     In another embodiment of present invention the second storage assembly  34  does not include a lifting frame  498 . Instead, the second storage assembly is located adjacent to the frame of separator sheet handling assembly  10  such that sheets  46  which are not delivered to the first storage assembly  30  are delivered off of an end of the separator sheet handling assembly  10  into a receptacle (e.g., a trash bin). 
     The constructions and aspects described above and illustrated in the drawings are presented by way of example only and are not intended as a limitation upon the concepts and principles of the present invention. As such, it will be appreciated by one having ordinary skill in the art that various changes in the elements and their configuration and arrangement are possible without departing from the spirit and scope of the present invention. Various features and advantages of the invention are set forth in the following claims.