Abstract:
A lap separator system opens a sheet in a pocket traveling in a direction at a given speed, the pocket having forward and rearward walls pivotally connected to one another and, together, defining a sheet-receiving opening, and includes a moveable separator carrier, a separator connected to the carrier, the separator carrier conveying the separator in the transport direction along the pocket at a speed greater than the given speed, and the separator sequentially contacting the rearward wall, the sheet in the pocket, and then the forward wall and sequentially releasing the rearward wall, at least a portion of the sheet in the pocket, and then the forward wall. The system can be part of a sheet-collating machine having a conveyor, a sheet feeding device, and many pockets. A method for opening a sheet includes displacing the separator to sequentially contact and release the walls and sheet.

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The invention lies in the field of printing presses. The present invention relates generally to a sheet-conveying apparatus, for example, for conveying newspapers, and, more particularly, to a sheet conveying apparatus having pockets moving on a track. In particular, the invention relates to a lap separator for separating forward and rearward laps of a folded first sheet material section in a pocket to allow nesting of a second section therein and a method for separating such laps. 
     2. Background Information 
     Sheet-conveying devices, in particular, devices for conveying newspapers, are required to be able to insert or nest or collate various sets of sheets inside one another. Specifically, to create a finished newspaper, a first folded section of the paper, taking the form of a folded sheet section, is opened and at least one second section of the newspaper is inserted between the two sides of the folded sheet section. It is possible that the second section is, itself, a section having third, fourth, or more other sections nested therein in the same manner as the first section. To process such sheets, in particular, newspapers, prior art conveying devices have an angle-shaped pocket that first picks up a first section, opens the first section, and then conveys the opened first section to a delivery station. Prior art systems including pockets include, for example, U.S. Pat. No. 4,133,521 to Müller and U.S. Pat. No. 5,213,318 to Newhall. A delivery unit drops the second section into the opened first section to create a nested paper with two sections. This process can be repeated for many different sections to create an entire newspaper. 
     There is a difficulty associated with the pocket properly opening the first section to the appropriate opening position. To facilitate proper opening, each section is formed with a lap. In other words, the two ends of the folded sheet section are not even. Typically, in a sheet-processing direction, the forward-most end of the folded sheet section is longer than the rear-most end of the folded sheet section. Thus, if the fold of the sheet section is at the bottom of the pocket, when viewing the ends of the folded sheet section in the pocket from above, the forward lap is higher than the rear lap. 
     In such a position, the folded sheet section can be opened if the forward, higher lap is secured by a device (applying a physical contact and/or air suction) and the pocket or folded sheet section is moved or tilted to allow gravity (possibly assisted with suction) to let the rear lap fall away from the forward lap. After the rear lap has fallen or is moved away from the forward lap, there exists an opening into which a second section can be inserted. Accordingly, a second section can be inserted into or nested within the first section. This combined section can then be inserted into a further section, and so on, to create a multiply nested set of sheets, typically, forming a common newspaper. 
     The securing device typically takes the form of a finger-shaped gripper. In the opening process, such a gripper is rotated or lowered onto the forward lap to secure the forward lap, and the forward sheet section, to a front wall of the pocket. Some examples of prior art gripper systems in such pockets include U.S. Pat. No. 4,723,770 to Seidel et al., U.S. Pat. No. 4,988,086 to Schlough, and U.S. Pat. No. 5,024,432 to Thünker et al. 
     U.S. Pat. No. 5,911,416 to Klopfenstein describes a sheet material conveying apparatus with a plurality of pockets moveable around a track to accept sheet material from sheet material feeders. These pockets permit, for example, a first outer section of a newspaper to first be fed into the pockets by a first sheet material feeder, and then an inner newspaper section to be inserted between the folds of the first outer newspaper section. The Klopfenstein apparatus uses a lift cam  20  to move a semicircular actuator gear  150  to rotate a drive shaft  110  so as to set a height for pocket feet  90  disposed on racks  80 . A pawl and ratchet mechanism prevents the pocket from opening. The sheet material can then be accepted and inserted into the pockets. To deliver the sheet material, a trip cam  22  can release the pawl and ratchet mechanism. Tracks  80  move to a lower position through a biasing spring, so that feet  90  release through operation of a driver cam  130 . The sheet material in the pocket can, thus, move out of the pocket from the bottom to be further conveyed or to be stacked. The entirety of Klopfenstein is hereby incorporated by reference. 
     U.S. Pat. No. 5,251,888 to Eugster purports to describe pockets moveable along an endless path. Each pocket is provided with two vertically adjustable stops  14  mounted displaceably in a pocket carrier  8 . A guide member  28  purportedly can be set to vertically adjust the stops  14  as the pockets are moved along the endless path. 
     Because sheet delivery devices travel at relatively high speeds, the window of time for gripping the forward lap is small. Accordingly, there is a need to expand the window of time for gripping the forward lap. Significantly, lap sizes are neither consistent nor equal. Therefore, expansion of the time window must also be able to compensate for variations in lap sizes. 
     SUMMARY OF THE INVENTION 
     It is accordingly an object of the invention to provide a lap separator for separating forward and rearward laps of a folded first sheet material section in a pocket to allow nesting of a second section therein and a method for separating such laps that overcome the hereinafore-mentioned disadvantages of the heretofore-known devices and methods of this general type and that expands the time window for separating the forward lap from the rearward lap while also accommodating variations in size of forward and rearward laps. 
     Commonly assigned U.S. patent application Ser. No. 09/662,277, entitled “SHEET MATERIAL CONVEYING APPARATUS WITH INDIVIDUALLY-ADJUSTABLE POCKETS” filed on Sep. 14, 2000, describes a plurality of manually-adjustable pockets, each having a setting device for adjusting a height of the pocket. 
     Commonly assigned U.S. patent application Ser. No. 09/702,012, entitled “SHEET MATERIAL CONVEYING APPARATUS WITH HEIGHT-ADJUSTABLE POCKETS” filed on Oct. 30, 2000, describes a plurality of manually adjustable pockets, each having a setting device for adjusting a height of the pocket so as to define a set height. 
     Commonly assigned U.S. patent application Ser. No. 10/178,645, entitled “ADJUSTABLE GRIPPING DEVICE FOR ADJUSTABLE SHEET RECEIVING POCKETS AND METHOD FOR ADJUSTING SHEET RECEIVING POCKETS” and filed concurrently herewith, describes a different gripper adjusting system  70  having an adjustable gripper  71  with two main parts, a gripper body  72  and an adjustment device  73  including a pivot  75 , a cam follower  77 , and an adjustment body  79  in the form of a two-arm rocker. Depending on a placement setting of a vertically adjustable cam  26 , the adjustment body  79  pivots and moves a nose  74  of gripper body  72  along the surface of upper front wall  52  away from or towards the uppermost edge of the rearward lap  63 . 
     Commonly assigned U.S. patent application Ser. No. 10/178,645 entitled “ADJUSTABLE GRIPPING DEVICE FOR ADJUSTABLE SHEET-RECEIVING POCKETS AND METHOD FOR ADJUSTING SHEET-RECEIVING POCKETS” and filed concurrently herewith, describes a different gripper adjusting system  70  where each gripper  71  is individually adjustable through a gripper plunger  73  having a plunger body  75  with a nose, a rod  76 , and a cam follower  77  attached to the end of rod  76 . The nose directly contacts and holds forward lap  61  of a section  6 , or holds the entire section  6 ,  61 ,  63 . Depending on a setting of a vertically adjustable cam  26  the nose moves away from or towards an upper edge of the rearward lap  63 . 
     Each of these commonly assigned applications are hereby incorporated by reference herein. 
     With the foregoing and other objects in view, there is provided, in accordance with the invention, a lap separator system for opening a sheet in a pocket traveling in a transport direction at a given speed, the pocket having forward and rearward walls pivotally connected to one another, the forward and rearward walls together defining an opening for receiving the sheet, the lap separator system including a moveable separator carrier, at least one separator connected to the separator carrier, the separator carrier adapted to convey the at least one separator in the transport direction along the pocket at a speed greater than the given speed, and the at least one separator adapted to sequentially contact the rearward wall, the sheet in the pocket, and then the forward wall and to sequentially release the rearward wall, at least a portion of the sheet in the pocket, and then the forward wall. 
     In accordance with another feature of the invention, the separator is adapted to sequentially release the rearward wall, at least a portion of the sheet in the pocket, at least another portion of the sheet in the pocket, and then the forward wall. 
     In accordance with a further feature of the invention, the track has elevational change sections for displacing the separator with respect to the pocket. Preferably, the sections include inclines for displacing the separator away from the pocket and/or declines for displacing the separator towards the pocket. 
     In accordance with an added feature of the invention, the separator carrier is a track, preferably, an endless track. 
     In accordance with an additional feature of the invention, the separator is a plurality of separators. Preferably, the separator is of a flexible material. The separator can be a brush, a finger-shaped extension extending towards the pocket, a row of finger-shaped extensions each extending towards the pocket, a cylindrical rod, and/or a rectangular column. 
     With the objects of the invention in view, there is also provided a sheet-opening system, including at least one moveable pocket having forward and rearward walls pivotally connected to one another, the forward and rearward walls together defining an opening for receiving at least one sheet, the at least one pocket adapted to travel in a transport direction at a given speed and a lap separator system for opening the at least one sheet in the pocket, the separator system having a moveable separator carrier, at least one separator connected to the separator carrier, the separator carrier adapted to convey the at least one separator in the transport direction along the at least one pocket at a speed greater than the given speed, and the at least one separator adapted to sequentially contact the rearward wall, the at least one sheet in the pocket, and then the forward wall and to sequentially release the rearward wall, at least a portion of the at least one sheet in the pocket, and then the forward wall. 
     With the objects of the invention in view, there is also provided a sheet-collating machine, including a conveyor adapted to travel in a transport direction at a given speed, at least one sheet feeding device disposed at the conveyor for feeding at least one sheet towards the conveyor, pockets each having forward and rearward walls pivotally connected to one another, the forward and rearward walls together defining an opening for receiving the at least one sheet, each of the pockets connected to the conveyor, adapted to receive the at least one sheet from the at least one sheet feeding device, and adapted to transport the at least one sheet along at least a portion of the conveyor in the transport direction, and a lap separator system for opening the at least one sheet in at least one of the pockets, the separator system having a moveable separator carrier, at least one separator connected to the separator carrier, the separator carrier adapted to convey the at least one separator in the transport direction along the at least one pocket at a speed greater than the given speed, and the at least one separator adapted to sequentially contact the rearward wall, the at least one sheet in the pocket, and then the forward wall and to sequentially release the rearward wall, at least a portion of the at least one sheet in the pocket, and then the forward wall. 
     In accordance with yet another feature of the invention, the separator carrier and/or the separator are adjustable in a vertical direction with respect to the pockets. 
     With the objects of the invention in view, there is also provided a method for opening a sheet within at least one sheet-receiving pocket of a sheet-collating device, including the steps of conveying the at least one sheet-receiving pocket along a transport path in a transport direction at a given speed, the pocket having forward and rearward walls pivotally connected to one another, the forward and rearward walls together defining an opening for receiving the sheet, placing the sheet in the at least one sheet-receiving pocket, conveying at least one separator on a separator carrier along a second transport path in the transport direction at a speed greater than the given speed, and sequentially contacting the rearward wall, the sheet in the pocket, and then the forward wall with the at least one separator and then sequentially releasing the at least one separator from the rearward wall, at least a portion of the sheet in the pocket, and then the forward wall. 
     In accordance with yet a further mode of the invention, the pocket is a plurality of pockets and the separator is a plurality of separators. 
     In accordance with yet an added mode of the invention, the second transport path is adjacent and/or follows the transport path. 
     With the objects of the invention in view, there is also provided a method for opening a sheet within a sheet-receiving pocket, including the steps of providing sheet-receiving pockets to be conveyed in a transport path, each pocket having forward and rearward walls pivotally connected to one another, the forward and rearward walls together defining an opening for receiving the sheet and displacing at least one separator to sequentially contact the rearward wall, the sheet in the pocket, and then the forward wall and then to sequentially release the at least one separator from the rearward wall, at least a portion of the sheet in the pocket, and then the forward wall. 
     “Rod” as defined herein can be any elongated structure. 
     Other features that are considered as characteristic for the invention are set forth in the appended claims. 
     Although the invention is illustrated and described herein as embodied in a lap separator for separating forward and rearward laps of a folded first sheet material section in a pocket to allow nesting of a second section therein and a method for separating such laps, it is, nevertheless, not intended to be limited to the details shown because various modifications and structural changes may be made therein without departing from the spirit of the invention and within the scope and range of equivalents of the claims. 
     The construction and method of operation of the invention, however, together with additional objects and advantages thereof, will be best understood from the following description of specific embodiments when read in connection with the accompanying drawings. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a diagrammatic perspective view of a sheet material conveying apparatus according to the invention; 
     FIG. 2A is a side view of a pocket according to the invention with certain elements omitted for clarity; 
     FIG. 2B is an enlarged side view of the pocket of FIG. 2A illustrating a detail of a gripper according to the invention; 
     FIG. 3 is a fragmentary perspective view of a pocket according to the invention with certain elements omitted for clarity; 
     FIG. 4 is a different, fragmentary perspective view of the pocket according to FIG. 3; and 
     FIGS. 5A through 5E are diagrammatic cross-sectional views illustrating sequential phases of a lap separation system according to the invention. 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     Referring now to the figures of the drawings in detail and first, particularly to FIG. 1 thereof, there is shown a diagrammatic representation of a sheet material conveying apparatus  100  having an endless track  101  for transporting a plurality of pockets  10  in transport direction  17 . Each pocket  10  includes moveable fingers  90  for defining a pocket height, an individual height setting mechanism  8 , and a releasable lock mechanism  9  for height setting mechanism  8 . Fingers  90  are movable about a pivot  96 . 
     At a setting area  1 , each pocket  10  can be set manually by setting mechanism  8  to move fingers  90  to at least one of two desired heights, for example, a setting for receiving 10_-inch folded products. Pockets  10  are stationary during setting, and the setting can occur outside setting area  1  as well, for example, by an operator moving about track  101 . Alternatively, pockets  10  can be moved to setting area  1 , the apparatus can be stopped, and each pocket  10  can be set. An automated robot for interacting with setting mechanism  8  also could be located at setting area  1  to move each pocket  10  to the proper height, as each pocket  10  is moved to and stopped at setting area  1 . 
     After a pocket  10  is set to a desired height, setting mechanism  8  is then locked in place by lock mechanism  9  so that the pocket height is set. After all pockets  10  are set, they are moved to pass beneath a first sheet material feed station  2  where, for example, a folded cover section  6  of a newspaper or other printed product, also referred to as a jacket, is delivered into pocket  10 . At a second and optional sheet material feed station  3 , a second section  7  may be inserted between forward and rear portions of cover section  6  to form a final printed product  12 . This process can be repeated for any number of feed stations  2 ,  3  to create a final product  12  having many nested sections  6 ,  7 . Accordingly, a time period between receipt in pocket  10  of section  6  from station  2  and placement of pocket  10  beneath station  3  defines the window of time for separating section  6  into a pocket to receive section  7  therein. 
     After receiving sections  6 ,  7 , pockets  10  can then pass a release station  4 , which releases lock mechanism  9 . Setting mechanism  8 , which is, preferably, spring-loaded, then releases fingers  90  so that the bottom of pocket  10  opens, and finished products  12  are delivered, for example, to a conveyor belt  11 . 
     As pockets  10  continue past release station  4 , pockets  10  pass through a reset station  5 , which can include a movable incline reset ramp  25  for interacting with a reset cam follower  156  (see FIG. 3) of setting mechanism  8  and a lock engagement device  35  for locking lock mechanism  9 . Pockets  10 , which are preferably all set to a common height, are then reset to the common height by reset ramp  25  and locked into place by lock engagement device  35  engaging lock mechanism  9 . 
     FIGS. 2A,  3 , and  4  show more details of pocket  10 . 
     Pocket  10  has an upper rear wall  54  and an upper front wall  52 , in between which is an opening  56  for accepting sheet material, for example, cover section  6 . Pocket  10  also has a side wall  44 . Pocket  10  also may have a lower rear wall  64  and a lower front wall  62 . 
     FIG. 2B is an enlarged view of the upper portion of pocket  10  illustrated in FIG.  2 A. FIG. 2B shows the area where a forward lap  61  of cover section  6  is held. To hold cover section  6  in place, a set of grippers  53 ,  55  are located at the top of upper front wall  52 . Grippers  53 ,  55  are shown coaxially disposed on a single shaft  57 , albeit in different rotational positions. However, alternatively, different sets of grippers can be disposed on different shafts, each being independently controlled. For example, grippers of one set can be longer than grippers of another set. 
     A non-illustrated control device pivots shaft  57  holding grippers  53 ,  55  between an engaged position and a disengaged position. In FIG. 2B, one gripper  53  is shown in the disengaged position and another gripper  55  is shown in the engaged position. In the engaged position, gripper  55  holds forward lap  61  of cover section  6  so that it is fixed with respect to upper front wall  52 ; cover section  6  being so held is shown diagrammatically in FIG. 2B with a dashed line. 
     Prior to the invention, section  6  separated according to a process described in the following text. 
     When cover section  6  is first deposited in opening  56 , the bottom (lowermost) edge of cover section  6  rests at the junction between fingers  90  and upper rear wall  54  as shown in FIG.  5 A. In the open position of pocket  10 , shown in FIGS. 2A and 5A, gravity causes cover section  6  to rest entirely against upper rear wall  54 . See FIG.  5 A. To begin a process for gripping cover section  6  with grippers  53 ,  55 , upper rear wall  54  is pivoted about axis  51  to contact upper front wall  52 , as shown in FIG.  5 B. Alternatively and/or additionally, the entire rear wall  54 ,  64  can be displaced towards front wall  52 ,  62 . When cover section  6  rests against upper front wall  52 , grippers  53 ,  55  are rotated into the engaged position and hold at least a portion of cover section  6  in place against upper front wall  52 . See FIGS. 2B,  5 C, and  5 D. If grippers  53 ,  55  are adjusted so that they extend no further than a top edge of rearward lap  63  of cover section  6 , then grippers  53 ,  55  only grip forward lap  61  of over section  6 . After which, forward lap  61  is held against upper front wall  52  and gravity and/or another device, such as a suction device  59 , carries rearward lap  63  of cover section  6  along with the rearward-moving upper rear wall  54 . Thus, an opening  56  is created between forward lap  61  and rearward lap  63  for receiving another section  7  therein, for example, from second sheet material feed station  3 . 
     Timing is important for such a process. Grippers  53 ,  55  are delayed from engaging forward lap  61  until after upper rear wall  54  positively placed forward lap  61  on upper front wall  52 . Time is also wasted by waiting until upper rear wall  54  and, with it, rearward lap  63 , fell rearward sufficiently far enough to create an opening  56  permitting faultless placement of section  7  therein. 
     The invention extends the window of time for this process by providing a lap separating system  70 . Lap separating system  70  includes at least one lap separator  72  moveably disposed on a lap separator carrier system  74  and operates as set forth in the following text. 
     Carrier system  74  is disposed near or at endless track  101 , which forms a portion of a pocket conveyor system. Carrier system  74  moves in transport direction  17  the same as track  101 . Preferably, carrier system  74  is an endless belt that follows pockets  10 , but moves at a different speed. Also, carrier system  74  can be adjustable in a vertical direction with respect to pocket  10 . Thus, a lap separator  72  can be adjusted to move closer to or further away from pocket  10 . Such adjustment can be a movement of the entire system  70 , or a movement of an individual lap separator  72 . System  70  can be preset to a particular format or system  70  can include an automatic control system with adjustment motors and sensors for determining a position of a forward lap  61  or another portion. 
     As shown in FIG. 5A, a section  6  is first deposited in pocket  10  at station  2  (which is only illustrated in FIG.  1 ). Sometime thereafter, preferably, immediately thereafter, upper rear wall  54  and section  6  must be pivoted towards upper front wall  52  to begin the process for opening section  6  to receive another section  7 . Accordingly, as shown in FIGS. 5A to  5 B, a lap separator  72  is moved in transport direction  17  along with pocket  10 , but faster than pocket  10 . As such, lap separator  72  catches up with pocket  10  and overtakes it. Preferably, lap separator  72  overtakes pocket  10  immediately after section  6  securely lies in pocket  10 . 
     Lap separator  72  has a length sufficient to contact a rearward side of upper rear wall  54  and impart a sufficient force to upper rear wall  54  to pivot upper rear wall  54  up to and against upper front wall  52 , thereby clamping section  6  between upper rear wall  54  and upper front wall  52 . Alternatively, if it is necessary to place an end of lap separator  72  lower with respect to pocket  10 , carrier system  74  can be configured, as shown in FIG. 5B, to lower lap separator  72  towards pocket  10 . Alternatively, or additionally, carrier system  74  can be configured, as shown in FIG. 5C, to raise lap separator  72  from pocket  10 . A lowering or raising portion of carrier system  74  will be dependent upon a function that lap separator  72  needs to perform with respect to pocket  10 . If lap separator  72  is not needed, it can be raised sufficiently far from pocket  10  such that lap separator  72  cannot contact any portion of pocket  10 . 
     FIG. 5B illustrates a point in time where lap separator  72  has fully pressed upper rear wall  54  against upper front wall  52 . In such a position, forward lap  61  clearly projects above rearward lap  63 . Preferably, lap separator  72  is of a material that allows lap separator  72  to flex or bend. Thus, as lap separator is pressed against pocket  10 , it flexes as shown in FIG.  5 D. 
     Even though lap separator  72  is traveling with pocket  10 , it is traveling faster. Accordingly, as lap separator  72  moves past or along pocket  10 , at a point in time shown in FIG. 5C, the end of lap separator  72  has completely moved past upper rear wall  54 . Because lap separator  72  is no longer pressing against upper rear wall  54 , gravity, or some other device, such as a non-illustrated biasing spring, moves upper rear wall  54  back to its starting position shown in FIG.  5 A. If rearward lap  63  is the same height or is shorter than upper rear wall  54 , then rearward lap  63  will be carried back with upper rear wall  5 , especially if upper rear wall  54  is provided with a suction device  59 . If, however, rearward lap  63  is taller than upper rear wall  54 , as shown in FIG. 5C, upper rear wall  54  will begin moving rearward in pocket  10  before rearward lap  63  moves at all because lap separator  72  will be pressing rearward lap  63  against upper front wall  52 . Lap separator  72  continues moving past pocket  10  and, therefore, at a later point in time, lap separator  72  is no longer exerting pressure against rearward lap  63  and only exerts pressure against forward lap  61 . When such pressure is released from rearward lap  63 , it can then move rearward to create opening  56  for receiving section  7  as shown in FIG.  5 D. 
     Throughout the time that lap separator  72  is pressing against upper front wall  52  (FIGS. 5B,  5 C,  5 D,  5 E), pressure is exerted against forward lap  61 . Especially after upper rear wall  54  and rearward lap  63  have fallen away from forward lap  61 , lap separator  72  is exerting pressure against forward lap  61  as shown in FIG.  5 E. Thus, grippers  53 ,  55  can move to secure forward lap  61  anytime after upper rear wall  54  and rearward lap  63  have fallen away from forward lap  61 . 
     At the latest, grippers  53 ,  55  must grip forward lap  61  immediately before section  7  is deposited inside section  6 . 
     Lap separator  72  contacts upper rear wall  54  immediately after pocket  10  receives section  6  and immediately begins moving in transport direction  17 . The movement speed of lap separator  72  defines how fast upper rear wall  54  and rearward lap  63  fall away from forward lap  61 . Because lap separator movement speed is relatively fast as compared to movement of pocket  10  along endless track  101 , using the invention, upper rear wall  54  and rearward lap  63  fall away from forward lap  61  well before pocket  10  is placed under station  3  to receive section  7 . Therefore, use of the invention speeds up separation of forward and rearward laps  61 ,  63 , and, consequently, expands the time window available for gripping forward lap  61  with grippers  53 ,  55 . Increasing the time window for gripping means that longer length grippers  53 ,  55  can be used. 
     Lap separator  72  can take any shape. It can be a single, solid, rectangular column extending into the plane of FIGS. 5A to  5 E across the entire width of pocket  10  and having a cross-section as illustrated in FIGS. 5A to  5 E. As such, the extent of the column into the plane is substantially greater than the vertical cross-section illustrated. Such a shape is possible because upper edges of upper rear wall  54 , rearward lap  63 , forward lap  61 , and upper front wall  52  are all parallel with respect to one another in a direction extending into the plane of FIGS. 5A to  5 E. Thus, a bottom edge of such a rectangular column will release each portion of a respective upper edge substantially simultaneously. 
     Alternatively, lap separator  72  can be a row of a plurality of finger-shaped devices extending from carrier system  74  towards a bottom of pocket  10  (i.e., in a direction of pivot  96 ). In contrast to the single rectangular column above, the extent of such finger-shaped devices into the plane of FIGS. 5A to  5 E is substantially smaller than the illustrated vertical cross-section. These finger-shaped devices can take any shape, including a cylindrical rod or a rectangular column. 
     In a third embodiment, lap separator  72  can be a single finger-shaped device extending from carrier system  74  towards a bottom of pocket  10 , the device having the same characteristics of the finger-shaped devices mentioned in the preceding paragraph. 
     In any of the three example embodiments, lap separator  72  can have a solid form. For example, the first embodiment would appear similar to a window squeegee. Alternatively, lap separator  72  can be a brush. 
     Preferably finger carrier system  74  is an endless belt having a plurality of removable, and, therefore, adjustable, individual lap separators  72  disposed along the extent of the endless belt. Positioning of lap separators  72  on the belt will, therefore, determine timing of lap separator&#39;s  72  action against a pocket  10 . 
     As set forth above, up until the invention, there was a difficulty associated with separating forward lap  61  of a first section  6  from rearward lap  63  to create a pocket therebetween into which second section  7  can be inserted or nested. The invention adds a new lap separating system to expand the window of time that grippers  53 ,  55  have to grip forward lap  61 . Simultaneously, the invention compensates for variations in size of the forward and rearward laps.