Patent Publication Number: US-8118295-B2

Title: Stitcher/stapler for binding multi-sheet collations and method of operating the same

Description:
RELATED INVENTIONS 
     This patent application relates to commonly-owned, co-pending application Ser. No. 12/604,755 entitled “TRANSPORT AND ALIGNMENT SYSTEM FOR PRODUCING VARIABLE THICKNESS COLLATIONS” and commonly-owned, co-pending application Ser. No. 12/604,797 entitled “RECONFIGURABLE STITCHER FOR BINDING CONSECUTIVE VARIABLE THICKNESS COLLATIONS”. 
     FIELD OF THE INVENTION 
     The present invention relates to apparatus for binding stacked sheets of material, and more particularly, to a binding apparatus for producing multi-sheet collations such as those processed by high volume mail piece inserter systems. 
     BACKGROUND OF THE INVENTION 
     Various apparatus are employed for arranging sheet material in a package suitable for use or sale in commerce. One such apparatus, useful for describing the teachings of the present invention, is a mail piece inserter system employed in the fabrication of high volume mail communications, e.g., mass mailings. Such mailpiece inserter systems are typically used by organizations such as banks, insurance companies and utility companies for producing a large volume of specific mail communications where the contents of each mailpiece are directed to a particular addressee. Also, other organizations, such as direct mailers, use mailpiece inserters for producing mass mailings where the contents of each mail piece are substantially identical with respect to each addressee. Examples of inserter systems are the 8 series, 9 series, and APS™ inserter systems available from Pitney Bowes Inc. located in Stamford, Conn., USA. 
     In many respects, a typical inserter system resembles a manufacturing assembly line. Sheets and other raw materials (i.e., a web of paper stock, enclosures, and envelopes) enter the mailpiece inserter as inputs. Various modules or workstations in the mailpiece inserter work cooperatively to process the sheets until a finished mail piece is produced. The precise configuration of each inserter system depends upon the needs of each customer or installation. 
     Typically, mailpiece inserters prepare mail pieces by arranging preprinted sheets of material into a collation, i.e., the content material of the mail piece, on a transport deck. The collation of preprinted sheets may continue to a chassis module where additional sheets or inserts may be added to a targeted audience of mail piece recipients. From the chassis module the fully developed collation may continue to a stitcher module where the sheet material may be stitched, stapled or otherwise bound. Subsequently, the bound collation is placed into a mailpiece envelope and conveyed to yet other stations for further processing. That is, the envelopes may be closed, sealed, weighed, sorted and stacked. Additionally, the inserter may include a postage meter for applying postage indicia based upon the weight and/or size of the mail piece. 
       FIGS. 1   a - 1   c  show the relevant components of a prior art chassis module/station  200  of an inserter system. The figures show the chassis module  200  conveying a sheet material  212  along a transport deck  214  (omitted from  FIG. 1   a  to reveal underlying components). The transport deck  214  includes a drive mechanism  216  for displacing the sheet material  212  as it slides over the transport deck  214 . In  FIG. 1   c , the transport deck  214  includes a low friction surface  214 S having a pair of parallel grooves or slots  214 G formed therein. Riding in the grooves or through the slots  214 G are fingers  216 F which extend orthogonally from the surface  214 S of the deck  214 . 
     Referring to  FIGS. 1   a - 1   c , the fingers  216 F are driven by a belt or chain  218   C1  which, in turn, wraps around a drive sprocket or gear  218 G. Furthermore, the fingers  216 F 1  are spaced in equal length increments while the fingers  216 F 2 , of adjacent chains  218   C1 ,  218   C2  are substantially aligned, i.e., laterally across the transport deck  214 . As such, a substantially rectangular region or pocket is established between the fingers  216 F 1 ,  216 F 2 . 
     Above the transport deck  214  are one or more feeder mechanisms  220 A,  220 B (two are shown for illustration purposes) which are capable of feeding inserts  222 , i.e., sheet material, to the transport deck  214 . The inserts  222  may be laid to build a collation  212  or may be added to the sheet material  212  (i.e., a partial collation) initiated upstream of the transport deck  214 . A controller (not shown) issues command signals to the feeder mechanisms  220 A.  220 B to appropriately time the feed sequence such that the inserts  222  are laid in the rectangular region  224  between the fingers  216 F 1 ,  216 F 2 . More specifically, as each pair of lateral fingers  216 F 1 ,  216 F 2  is driven within the grooves or slots  214 G, one edge of the sheet material  212  is engaged to slide the collation  212  along the transport deck  214 . As the sheet material  212  passes below the feeding mechanisms  220 A,  220 B, other sheets or inserts  222  are added. At the end of the transport deck  214 , the fingers  216 F 1 ,  216 F 2  drop beneath the transport deck  214  such that the collation (i.e., the combination of the sheet material and inserts  222 ) may proceed to subsequent processing stations. 
     While the drive mechanism  216  of the prior art provides rapid transport of collated sheet material  212 ,  222 , the stacked sheets/inserts  222  fed by the feeding mechanisms  220 A,  220 B can become misaligned in the rectangular space or pocket  124  provided between the fingers  216 F 1 ,  216 F 2 . That is, inasmuch as the pocket  224  is oversized to accept the sheets or inserts  222 , the inserts  222  can become misaligned due to a lack of positive registration surfaces on all sides of the collation  212 ,  222 . 
     Various mechanisms are employed to vary the pocket size, i.e., sometimes referred to as the “pitch”, between the chassis fingers. The ability to change pitch not only enables greater efficiency, i.e., a greater number of pockets for inserts, but also minimizes the misalignment of inserts being laid on a collation. Notwithstanding the ability to minimize pocket size, it will be appreciated that without positive restraint on all free edges of the collation, individual sheets or inserts will be misaligned. Consequently, prior art inserters commonly employ complex registration mechanisms or jogging devices to align the free edges of a collation. For example, inserters may employ a series of swing arms which pivot onto the transport deck, i.e., into the conveyance path of the collation. The swing arms engage and align the leading edge of a collation, i.e., the edge opposite the fingers. While the swing arms effectively maintain alignment of the collation, the mechanical complexity associated with the pivoting mechanism is a regular source of maintenance, jamming and/or failure. 
     In the absence of such swing arms, an inserter may employ other jogging mechanisms to align the edges of the collation. Such jogging mechanisms often employ a complex arrangement of rotating cams/discs which tap or “jog” each edge by a predetermined displacement. While such rotating cam mechanisms are useful for aligning relatively thin collations, e.g., less than fifty (50) sheets of material, thick collations can be more difficult to align due to the weight of the stacked sheets. That is, inasmuch as the weight increases the frictional forces developed between individual sheets of material, i.e., especially the lowermost sheets of the collation, it is more difficult to effect the requisite movement between sheets to align the edges of the collation. As a consequence, the edges of misaligned sheets can be damaged or torn by the motion/action of such prior art jogging mechanisms. 
     Additionally, many mailpiece inserters employ mechanisms, e.g., a stitcher or a stapler, to bind the collations as they travel along the transport and alignment system. These binding mechanisms must be manually adjusted depending upon the anticipated thickness of a collation within a particular mail run. That is, the size of the stitch or staple must be anticipated to penetrate and bind the collation. This operation requires significant operator intervention and does not accommodate consecutive collations which vary in thickness. With respect to the latter, stitchers/staplers of the prior art cannot bind collations which vary in thickness from one collation having a thickness of, for example, one-half inch (½″), to a subsequent or consecutive collation having a thickness of, for example, three-quarter inches within the same mail run. This is due to the fixed or constant thickness staples used in, or stitches produced by, the stitcher/stapler. While some small variation may be accommodated by the same size stitch or staple, stitcher/staplers of the prior art are generally limited to binding constant thickness collations. 
     In view of the foregoing it will be appreciated that transport and alignment systems, especially those which employ binding mechanisms along the feed path, are limited in terms of their throughput or processing speed. That is, in view of the time required to jog, align, bind and transport collations along the feed path, these systems can only process a fixed number of collations per unit time. 
     A need, therefore, exists for a system and method for producing multi-sheet collations which improves reliability, increases throughput, and minimizes mechanical complexity. 
     SUMMARY OF THE INVENTION 
     A system and method is provided for binding variable thickness multi-sheet collations. The system includes first and second processing stations including a stitcher and stapler, respectively and a means for determining the thickness of a multi-sheet collation. A processor is responsive to a thickness value signal and selects one of the first and second processing stations to bind the multi-sheet collation. A conveyance system then transports the multi-sheet collation to the selected one of the first and second processing stations. 
     The method comprises the steps of: stacking sheet material to produce a multi-sheet collation, determining the thickness of the multi-sheet collation, and selecting an apparatus to bind the multi-sheet collation from one of at least two binding apparatus based upon the thickness of the multi-sheet collation. The multi-sheet collation is then conveyed along a feed path to a selected one of the binding apparatus. The method further includes the steps of disposing the multi-sheet collation between a pair of opposed registration members and aligning opposed edges of the multi-sheet collation by oscillating at least one of the registration members into and out of engagement with at least one of the opposed edges based upon the thickness of the multi-sheet collation. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Further details of the present invention are provided in the accompanying drawings, detailed description, and claims. 
         FIG. 1   a  is a perspective view of a prior art chassis drive mechanism employed in a mail piece inserter system. 
         FIG. 1   b  is a profile view of the prior art chassis drive mechanism shown in  FIG. 1   a  including feed mechanisms for building a sheet material collation. 
         FIG. 1   c  is a broken-away isometric view of the prior art chassis drive mechanism of  FIG. 1   a  to more clearly show chain driven fingers for conveying the sheet material collation along a transport deck. 
         FIG. 2  is an isometric view of a stitcher/stapler module having a transport and alignment system including a pair of belts having pusher fingers to convey a multi-sheet collation along a feed path, and a system of alignment mechanisms disposed alongside and between the fingers to jog and align the edges of the collation. 
         FIG. 3  is a block diagram of various components of a mailpiece inserter system including a processor for controlling the operation of a stitcher/stapler module and processing thickness data/sheet count information derived from one of a variety of sources. 
         FIG. 4  is a broken away isometric view of the stitcher/stapler module of  FIG. 2  to reveal the relevant details of the transport and alignment system including an feed input station for stacking a multi-sheet collation, and first and second processing stations disposed downstream of the feed input station for aligning the leading, trailing and lateral side edges of the multi-sheet collation. 
         FIG. 5  is a schematic side view of the first and second processing stations each including pairs of repositionable alignment mechanisms which may be: (i) extended upward between the first and second conveyor belts to jog/align the leading and trailing edges of the multi-sheet collation, and (ii) retracted below the support surfaces of the conveyor belts to facilitate to transport along the feed path immediately prior to, and following alignment of, the multi-sheet collation. 
         FIGS. 6   a  and  6   b  depict exploded and assembled views, respectively, of a typical trailing edge alignment mechanism including a four-bar linkage arrangement for displacing a registration member of the alignment mechanism from an idle position below the conveyor belts to an active position above the conveyor belts. 
         FIGS. 7   a  and  7   b  depict exploded and assembled views, respectively, of a typical leading edge alignment mechanism including a four-bar linkage arrangement for displacing the registration member from the idle to active positions, and a linear guide/actuator assembly for imparting pure linear motion to the registration member when jogging the multi-sheet collation during alignment operations. 
         FIGS. 8   a  through  8   d  depict schematic views of a reconfigurable stitch head adapted to vary the length of each binding stitch based upon thickness data/sheet count information of the multi-sheet collation. 
     
    
    
     DETAILED DESCRIPTION 
     The following detailed description discusses three related, yet patentably distinct inventions related to processing sheet material collations. A first relates to a stitcher/stapler for binding multi-sheet collations and method for controlling the same. A second relates to a transport and alignment system for producing variable thickness collations and a third relates to an adjustable stitcher for binding consecutive variable thickness collations. While each will be discussed under a separate heading, the description relates and defines elements common to all of the inventions. 
     Further, the inventions will be described in the context of a stitcher/stapler for use in a mailpiece inserter. In the broadest sense, however, the stitcher/stapler, transport/alignment system, and adjustable stitcher of the present invention may be integrated with, and/or receive input from, any sheet handling apparatus adapted to produce/process multi-sheet collations. While the inventions may be particularly useful for processing/producing mail communications, it should be appreciated that the inventions are broadly applicable to any apparatus/system which requires binding, transport and alignment of stacked sheets of material, i.e., a multi-sheet collation. As used herein, the term “collation” is any multi-sheet stack of material, i.e., having at least two (2) sheets, such as that required for fabricating, books, pamphlets, mailpiece content material etc. 
     Stitcher/Stapler for Binding Multi-Sheet Collation and Method of Operation 
     In  FIGS. 2 and 3 , a stitcher/stapler  10  is adapted to stack, transport, align and bind consecutive multi-sheet collations  12  which vary in thickness. That is, the stitcher/stapler  10  is adapted to process consecutive collations which comprise as few as two (2) sheets to as many as one-hundred and fifty (150) sheets. It should be appreciated, however, that total number of sheets in a particular collation will generally be governed by the ability of a processing station to bind sheet material. 
     In the described embodiment, the stitcher/stapler  10  includes three serially-arranged processing stations including an feed input station  14 , a first processing station  16 , and a second processing station  18  The stitcher/stapler  10  receives sheet material  12 S from an upstream module (not shown) of a sheet handling apparatus, e.g., a mailpiece inserter  24  (see  FIG. 3 ), and accumulates/stacks of sheet material at the feed input station  14 . The thickness of the multi-sheet collation  12  is determined to ascertain which of the subsequent processing stations  16 ,  18  will be most effective to bind the multi-sheet collation  12 . The first processing station  16 , immediately downstream of the feed input station  14 , includes a stitcher  20  (described and illustrated in greater detail below) to bind the collation by a variable length “stitch”, i.e., a length of wire which is cut/formed to produce a pair of prongs connected by a central web (similar to a staple, however, the ends of each prong are not sheared so as to form a penetrating point). The second processing station  18  includes a stapler  22  which binds the collation by a fixed length “staple”, i.e., a conventional U-shaped fastener having a pair of penetrating legs connected by a central crown. 
     The principle difference between the two, i.e., the stitcher  20  of the first processing station  16  and the stapler  22  of the second processing station  18 , relates to the capacity and/or ability of each to bind a collation. The stitcher  20  provides the capability to bind many collations before a requirement to reload a supply of stitching wire. That is, the stitcher  20  employs a relatively large spool of wire to provide a large supply of stitching material to bind multiple collations/documents. However, due to the requirement to shape each stitch from a supply of wire spool, the gauge of the wire and/or its yield strength properties, must be relatively low to facilitate the formation of the stitch, i.e., bending the wire to shape. A stapler  22 , on the other hand, provides the ability to bind thick collations, e.g., a thickness greater than about forty-five thousands of an inch (0.45″) or greater than about ninety (90) sheets of bond grade paper, but is limited in terms of the number of collations/documents that can be bound. With respect to the latter, the staples, which are “preformed”, are fabricated from high yield strength, high stiffness materials. As a result, the legs of each staple can be fabricated to a length sufficient to penetrate thick collations without buckling. However, since the staples are preformed and packaged in strips having a finite number, only a small number of collations may be bound before the stapler  22  must be reloaded. In view of these differences, the stitcher/stapler module  10  of the present invention obtains information concerning the thickness of the multi-sheet collation such that each may be directed to the most appropriate downstream station for subsequent processing. This feature is discussed in greater detail in the subsequent paragraphs. 
     In  FIG. 3 , thickness/sheet count information  30  is used for several operations of the stitcher/stapler  10  including operations which: (i) select the processing station  16 ,  18  best suited to bind the collation  12 , (ii) control the transport and alignment of the multi-sheet collations  12  at each of the processing stations  16 ,  18 , and (iii) control the stitching operation at the first processing station  16  (i.e., the length of stitch, spacing between the anvil/clincher and the striker/ram, etc.) Specifically, the thickness information  30  may be obtained by (i) reading a scan code data  32  printed on the first sheet of the multi-sheet collation  12 , (ii) employing a sheet counter  34  in combination with sheet thickness data input by an operator, (iii) obtaining the number of sheets directly from the job data  36  of the mail run (i.e., from the application program code which generates each sheet printed in the mail run), (iv) directly measuring the thickness via a thickness measurement probe  38 , once the collation  12  has been stacked. In the described embodiment, a scanner (not shown), upstream of the stitcher/stapler module  10 , reads the scan code data  32  to obtain the number of sheets contained in the collation  12 . A processor  40 , controlling the operation of the mail piece inserter  24  (including the stitcher/stapler module  10 ), determines the thickness of the collation  12  as the product of the number of individual sheets  12 S multiplied by the thickness of each sheet. An operator may be prompted i.e., via a keyboard or other input device  42  to enter the type or characteristics (i.e., weight, bond, copy, etc.), of the sheet material such that the processor  40  may calculate the thickness of the collation  12  to be bound. 
     The processor  40  uses the thickness data/sheet count information to convey the multi-sheet collation  12  from the input feed station  14  to the stitcher  20  at the first processing station  16 , or to the stapler  22  at the second processing station  18 . That is, the processor  40  is responsive to a thickness value signal TS and, if the thickness of the collation is greater than (or less than) a threshold value (X), the collation  12  is transported to one of the processing stations  16 ,  18 . In the described embodiment, if it is determined that the collation  12  is less than or equal to about forty-five thousands inches (0.45″) in thickness, the collation  12  is transported to the first station  16  for processing. Therein, the collation  12  is bound by the stitcher  20  which is capable of varying the length of the stitch such that the stitch optimally extends through the collation. That is, the wire of the stitcher  20  is cut to a length such that the prongs thereof extends through the collation and the anvil of the stitcher  20  clinches the ends to an optimal length, i.e., sufficiently long to capture all of the sheets without overlapping the ends of each prong. In the described embodiment, the stitcher  20  is capable of varying the length of each stitch, i.e., from one collation to a subsequent collation. While this aspect of the invention will be discussed in greater detail below i.e., when describing the reconfigurable stitcher illustrated in  FIGS. 8   a  through  8   d , suffice it to say at this juncture, that the stitcher  20  is adapted to: (i) vary the length of the wire which forms each stitch, (ii) center the web relative to the striker/ram which drives the stitch through the collation, and (iii) vary the strike distance i.e., the distance between the striker/ram and the anvil. 
     If it is determined that the thickness of the collation  12  is greater than about forty-five thousands inches (0.45″), the collation  12  is transported to the second station  18  for processing. Therein, the collation  12  is bound by the stapler  22  which is capable of penetrating the thick collation without bending/buckling. That is, since each staple is fabricated from a high yield strength material, the legs of each staple are highly stabile in buckling and penetrate the collation without bending. 
     Transport and Alignment System for Producing Variable Thickness Collations 
     As discussed above, the multi-sheet collation  12  is conveyed along a feed path FP of the stitcher/stapler  10  to one of the processing stations  16 ,  18  depending upon the collation thickness/sheet count information  30 . In  FIGS. 4 and 5 , the transport and alignment system comprises first and second belts  54   a ,  54   b  (best seen in  FIG. 4 ) which wrap around, and are driven by, a plurality of rolling elements  56 . That is, one or more rotary drive motors M is coupled to, and drives, at least one of the rolling elements  56  associated with each of the belts  54   a ,  54   b . In the described embodiment, the belts  54   a ,  54   b  are cogged to engage teeth disposed about the periphery of the rolling elements  56 . The first and second belts  54   a ,  54   b  slideably engage, and are each supported by, a rigid support structure disposed beneath the respective belts  54   a ,  54   b  to mitigate catenation thereof between the rolling elements  56 . In the described embodiment, the rigid support structures are elongate bars  58  (see  FIG. 2 ) having a width dimension (transverse to the feed path FP of the collation  12 ) approximately equal to the width of each belt. As a consequence, the belts  54   a ,  54   b  and bars  58  define a space or gap therebetween to allow for binding apparatus, i.e., the stitcher  20  and stapler  22 , to access the underside of the multi-sheet collation  12 . Furthermore, the spacing between the first and second belts  54   a ,  54   b  mitigates skewing of the multi-sheet collation  12 . 
     Each of the belts  54   a ,  54   b  includes a plurality of spaced-apart fingers  60  which are aligned along the conveyance/feed path FP to convey the multi-sheet collation  12  from the feed input station  14  to one of the downstream processing stations  16 ,  18 . The fingers  60  project upwardly, i.e., orthogonally, from each of the belts  54   a ,  54   b  and engage the trailing edge  12 T of the multi-sheet collation  20  at two points. Furthermore, the belts  54   a ,  54   b  are aligned across the feed path FP and driven in unison to “push” the collation  12  along the feed path FP to one of the two processing stations  16 ,  18 . 
     In  FIGS. 4 and 5 , perspective and side views, respectively, of the belts  54   a ,  54   b  are shown to reveal opposing alignment mechanisms  62   a ,  62   b  comprising pairs of registration members  64   a ,  64   b  disposed along the feed path FP and between the first and second conveyor belts  54   a ,  54   b . Functionally, the alignment mechanisms  62   a ,  62   b  are operative to align the opposed edges, e.g., leading and trailing edges, of the multi-sheet collation  12  as each collation comes to rest at one of the processing stations  16 ,  18 . Once aligned, the collation  12  is bound by either the stitcher  20  or stapler  22 , depending upon which processing station  16 ,  18  has been selected to bind the collation  12 , i.e., as determined by the processor  40 . 
     More specifically, and referring  FIGS. 4 ,  5 , and  6   a  through  7   b , each of the registration members  64   a ,  64   b  extends transversely across the feed path FP and has a generally L-shaped cross section defined by a base  66  and a registration wall  68  disposed orthogonally from the base  66 . Each registration wall  68  defines a registration surface  68 R which is repositionable from an idle position (shown in dashed lines in  FIG. 6   b ), below the support surface  54 S (also referred to as the “transport deck”) of each of the belts  54   a ,  54   b , to an active position (shown in solid lines in  FIG. 6   b ) above the support surface  54 S of the belts  54   a ,  54   b . In the idle position, the collation  12  moves over one or both of the registration members  64   a ,  64   b  and may be conveyed from the feed input station  14  to either of first or second processing stations  16 ,  18 . Alternatively, with all of the registration members  64   a ,  64   b  in the idle position, the collation  12  may be conveyed across the entire stitcher/stapler  10  to another downstream processing station, i.e., without being bound at either the first or second processing stations  16 ,  18 . 
     In the active position, at least one of the registration members  64   a ,  64   b  is adapted to oscillate forward and aft, i.e., along the feed path FP, to align the edges of the collation  12 . In the described embodiment, the downstream registration member  64   b  (see  FIGS. 4 and 7   b ) of each pair, i.e., the registration member  64   b  in contact with the leading edge  12 L of the collation  12 , oscillates forward and aft to align the sheets of the collation  12 . Although, it should be appreciated that either or both of the registration members  64   a ,  64   b  may be displaced to align the collation  12 . 
     To ensure complete and accurate registration of large collations, e.g., those having more than ninety (90) sheets or having a thickness greater than about 0.3 inches, the downstream registration member  64   b  of each pair oscillates for eight (8) cycles and is displaced a distance of about 0.25 inches with each cycle. However, to increase throughput, i.e., the number of collations processed (i.e., bound via the stitcher  20  or stapler  22 ), the number of cycles may be varied depending upon the thickness of the collation  12 . For example, a collation  12  having as few as ten (10) sheets, or a thickness less than about 0.1 inches, the registration member  64   b  may be cycled three (3) times. Similar to the selection of the appropriate processing station  16 ,  18 , thickness data  30 , or the number of sheets in each collation  12 , is used by the stitcher/stapler module  10  to determine the optimum number of cycles for aligning the sheets of each collation  12 . That is, the processor  40  acquires the thickness information  30  and varies the number of cycles depending upon the collation thickness or sheet count. 
     To further improve throughput, the processor  40  may control the conveyance system, (i.e., the belts  54   a ,  54   b , rolling elements  56  and drive motor M), to use the first and second processing stations  16 ,  18  as buffer stations. That is, when the stitcher/stapler  10  is not active, i.e., functioning only as a transport system, the processing stations  16 ,  18  may serve to hold/retain collations  12  (unbound collations) so that other mailpiece inserter stations e.g., folding, insertion and/or print stations (not shown) downstream of the first and second processing stations  16 ,  18  may process the mailpiece content material. 
     In  FIGS. 5 through 7   b , each of the registration members  64   a ,  64   b  pivotally mounts to a first displacement mechanism  70  operative to: (i) raise and lower the registration members  64   a ,  64   b  into and out of the idle and active positions, and (ii) oscillate at least one of the registration members  64   a ,  64   b  to align the sheets of the collation  12 . In the described embodiment, the displacement mechanism  70  comprises a plurality of links  72 ,  74  pivotally mounting at one end to an intermediate fitting  76 , and pivotally mounting at the other end to the base  66  of a respective one of the registration members  64   a ,  64   b . The intermediate fitting  76  includes a mounting plate  78  and at least one arm  80   a  projecting upwardly therefrom. In the described embodiment, the intermediated fitting  76  includes a pair of clevis arms  80   a ,  80   b  projecting from each side of the mounting plate  78  for additional stability. 
     The mounting plate  78  of each intermediate fitting  76  is mounted to a center rail  10 R (see  FIG. 4 ) of the stitcher/stapler  10  by a clamp attachment  82 . As such, the entire displacement mechanism  70  and respective one of the registration members  64   a ,  64   b  may be released, repositioned, and reaffixed to the rail  10 R via locking cams  84 . That is, to facilitate adjustment of the registration members  64   a ,  64   b , i.e., the spacing therebetween to accommodate dimensional changes in the size of collations  12 , the locking cams  84  provide an ability to quickly disconnect/reconnect the displacement mechanism  70  along the center rail  10 R. 
     Each displacement mechanism  70  includes a first pneumatic actuator  86  which is disposed between the base  66  of the respective registration member  64   a  or  64   b , and the mounting plate  78 . In the described embodiment, the first pneumatic actuator  86  includes a linear piston/cylinder disposed between the clevis arms  80   a ,  80   b  of the intermediate fitting  76 . A pneumatic valve  88  provides pressurized air PA 1  (see  FIG. 6   b ) to the actuator  86  of respective displacement mechanism  70  to displace the registration wall  68  into and out of the idle and active positions. 
     In  FIG. 6   b , an examination of the displacement mechanism  70  reveals that the links  72 ,  74 , intermediate fitting  76 , and base  66 , produce a four-bar linkage defined by line segments AB, BC, CD and DA. The four-bar linkage arrangement can be configured, i.e., depending upon the length of the links  72 ,  74  and the location of the respective pivot points A, B, C, D, to perform the dual functions of rotation and translation of the respective one of the registration members  64   a ,  64   b . That is, the four-bar linkage arrangement can displace the respective one of the registration members  64   a ,  64   b  to rotate above and below the surface  54 S of the belts  54   a ,  54   b  while also producing a substantially linear displacement i.e., forward and aft along the feed path FP, to jog and align the edges  12 L,  12 E of the collation  12 . With respect to the latter, such linear displacement will be accompanied by a small angular displacement, which, depending upon the geometry of the stitcher/stapler  10 , may or may not be tolerated. 
     In  FIGS. 7   a  and  7   b , pure linear translation of the displacement mechanism  70  may be effected by a linear guide  90  disposed in combination with a second pneumatic actuator  92 . More specifically, the linear guide  90  is disposed between the intermediate fitting  76  and the clamp attachment  82  and includes at least one sled fitting  94  affixed to the underside of the intermediate fitting  76 , i.e., to the underside of the mounting plate  78 , for slideably engaging a linear guide rail  95  affixed to an upper surface of the clamp attachment  82 . The second pneumatic actuator  92  is attached at one end, via a flange fitting  96 , to the clamp attachment  82 , and at the other end, via a bracket  97 , to the underside of the mounting plate  78 . A pneumatic valve  98  provides pressurized air PA 2  (see  FIG. 7   b ) to the second pneumatic actuator  92  to effect linear translation of the displacement mechanism within the linear guide  90 . Recalling that only the registration members  64   b  associated with the leading edge of the collation  12  may be used to jog the collation  12 , only the displacement mechanism  70  associated with downstream registration member  64   b , associate with each processing station  16 ,  18  may be adapted to include the linear guide  90  and pneumatic actuator  92 . 
     Thus far, the transport and alignment system has been described in the context of a stitcher/stapler  10  having a requirement to jog and align the leading and trailing edges of the multi-sheet collation  12 . While the transport and alignment system may employ conventional alignment devices/apparatus for guiding/aligning the lateral side edges of the collation  12 , e.g., rotating cams or converging side rails (not shown), the present invention employs a novel side registration system  100 , seen in  FIGS. 2 and 4 , which spans all of the processing stations, i.e., the feed input station  14 , and the first and second processing stations  16 ,  18 . More specifically, the side registration system  100  comprises a second pair of registration members  104   a ,  104   b  each having registration surfaces  104 R (only one of the registration members  104   b  is shown in  FIG. 4 ) disposed adjacent each of the first and second conveyor belts  54   a ,  54   b . The registration members  104   a ,  104   b  extend the length of the processing stations  14 ,  16 ,  18  and, similar to the first pair of registration members  64   a ,  64   b , have a generally L-shaped cross sectional configuration. The spacing between the registration members  104   a ,  104   b , i.e., the spacing across the feed path FP, may be adjusted to accommodate collations  12  which may vary in width dimension. Inasmuch as these registration members  104   a ,  104   b  do not cross the feed path, there is no requirement to raise or lower each relative to the surface  54 S of the conveyor belts  54   a ,  54   b . On the other hand, similar to the first pair of registration members  64   a ,  64   b , at least one of the second pair of registration members  104   a ,  104   b  is adapted to oscillate in a transverse direction, i.e., toward and away from the conveyor belts  54   a ,  54   b  to align the side edges  12 SE of the multi-sheet collation  12 . Although, it should be appreciated that either or both of the registration members  104   a ,  104   b  may be displaced to align the side edges  12 SE of the collation  12 . 
     In the described embodiment, a second displacement mechanism  106  is attached to each of the registration members  104   a ,  104   b  and at least one of the second displacement mechanisms  106  is operative to oscillate and jog the side edges of the multi-sheet collation  12 . While the second displacement mechanism  106  and registration members  104   a ,  104   b  may function to align the side edges  12 SE at any or all of the processing stations  14 ,  16 ,  18 , side registration of a collation  12  will generally commence at either the first or second processing stations  16 ,  18  where the collation  12  will be bound, i.e., by the stitcher  20 , or stapler  22 . Similar to the first pair of registration members  64   a ,  64   b , at least one of the second pair of registration members  104   a  or  104   b  is operative to cyclically or repetitively engage a lateral side edge  12 SE of the collation  12 . In the described embodiment, the displacement of each oscillation for aligning the side edges  12 SE will be about 0.25 inches, i.e., the same as the displacement required for aligning the leading and trailing edges  12 L,  12 T. The other of the registration members  104   a , or  104   b  remains essentially stationary to react the impact forces generated by the opposing one of the registration members  104   a ,  104   b . With respect to the latter, the second displacement mechanism  106  associated therewith is principally operational to adjust the location of the respective one of the displacement mechanisms  106 . 
     The processor  40  controls the second displacement mechanisms  106  associated with the side registration system  100 , i.e., to oscillate at least one of second pair of registration members  104   a ,  104   b , using the same thickness data  30  or sheet count information obtained for cycling the first displacement mechanism  70 . That is, should the thickness data  30  or sheet count require eight (8) cycles by one or both of the first displacement mechanism  70 , e.g., collations  12  having more than ninety (90) sheets, then the processor  40  will command one or both of the second displacement mechanisms  106  to cycle by an equivalent number. Similarly, should the thickness data  30  or sheet count require three (3) cycles, the processor  40  will control the second displacement mechanism  106  accordingly. The number of cycles will generally decrease from a maximum of about eight (8) cycles to a minimum of about three (3) cycles as the thickness/sheet count, of the collation  12  decreases from greater than about ninety (90) sheets to a minimum of two (2) sheets. It will be recalled that such variation in the number of cycles, i.e., as a function of the collation thickness/sheet count, serves to optimize throughput. 
     The second displacement mechanism  106  may use any of a variety of actuators to displace and cycle the registration members  104   a ,  104   b . In the described embodiment, the second displacement mechanism  106  employs a pair of linear actuators  108  (see  FIG. 4 ) disposed at each end of the respective one of the registration members  104   a ,  104   b  to ensure proper alignment of the collation  12 , whether the collation  12  is processed at the first or second processing stations  16 ,  18 . 
     Reconfigurable Stitcher for Binding Consecutive Variable Thickness Collations 
     As previously discussed, the thickness data/sheet count information  30  is used to control the stitching operation at the first processing station  16 . The thickness data/sheet count  30  may be generated by any of a variety of modules/sensor of the mailpiece inserter  24  or stitcher/stapler  10  including: (1) scan code data  32  (see  FIG. 3 ) printed on a sheet of the mailpiece content material, e.g., the first sheet of each collation  12 , (ii) a sheet counter  34  in combination with sheet thickness data input by an operator, (iii) mail run data  36 , i.e., obtained directly from the application software (mail run data file) used to produce the content material, or (iv) a thickness measurement device, e.g., a thickness probe  38 . 
     In  FIGS. 8   a  through  8   d , the stitcher  20  may be reconfigurable to vary the length of each binding stitch  120  based upon the thickness T of the multi-sheet collation  12 . More specifically, the stitcher  20  comprises a stitch head  122  disposed beneath the collation  12  and a clinch head or anvil  124  disposed above the collation  12 . Consequently, the stitcher  20  drives the prongs P (see  FIG. 8   d ) of each binding stitch  120  upwardly through the lowermost or bottom sheet  12 B while the clinch head  124  crimps the ends PE of each prong P against the top or uppermost sheet  12 U of the collation  12 . In the described embodiment, the stitch head  122  is disposed between the first and second conveyor belts  54   a ,  54   b , though it will be appreciated that the stitch head may be disposed to either side of the belts  54   a ,  54   b . Furthermore, while a single stitcher  20  is depicted, it will be appreciated that several stitchers  20  may be juxtaposed across the width, or disposed in tandem along the length, of the multi-sheet collation  12 , to bind the collation  12  at several locations. 
     In  FIG. 8   a , the processor  40  receives thickness data  30  in connection with each collation  12  conveyed to the first processing station. The processor  40  uses this data/information  30  to determine the length of wire  120 W used to generate the respective binding stitch  120 , i.e., a stitch specifically tailored in length to bind a collation  12  of a particular thickness dimension T. The processor  40  issues a first signal to a first input actuator  134 , i.e., a rotary actuator, which advances wire  120 W, through the nip of a pair of rollers  128 , and across a pair of spaced-apart bending beams  130   a ,  130   b  of the stitch head  122 . Furthermore, the wire  120  is disposed beneath a forming block  132  which cooperates with the bending beams  130   a ,  130   b  to form the prongs P about the squared edges of the forming block  132 . Wire to form the stitch  120  may be drawn from a conventional spool  138  mounted to the housing of the stitcher/stapler  10 . In addition to the thickness T of the collation  12 , which determines the minimum length of the prongs P required to penetrate the collation  12 , other dimensions needed to perform this operation include: (i) the width of the web W, i.e., the length of wire between the prongs, and (ii) the end length LE (see  FIG. 8   d ) of the prong end PE i.e., the portion protruding through, and securing the collation. 
     The processor  40  issues a second signal S 2  to a second input actuator  140  to center the wire  120 W across the bending beams  130   a ,  130   b . Additionally, the processor  40  issues a third signal S 3  to a third input actuator  142  to displace several components of the stitch head  122 , i.e., internal structure of the stitch head  122  which forms the stitch  120 , upwardly toward the underside of the collation  12 . That is, as third input actuator  142  strokes upwardly, portions of the upward displacement, denoted by lines D 1 , D 2  and D 3  actuate one or more connected elements. 
     A first portion of the stroke D 1  causes a shearing device  142  to cut the stitch wire  120 W. This motion can be conveyed directly to the shearing device  142  or via cams connected to one of the bending beams  130   a ,  130   b . In  FIG. 8   b , a second portion of the stroke D 2  displaces the bending beams  130   a ,  130   b  upwardly. In this portion of the displacement, the stitch wire  120 W falls, and is guided, within a pair of grooves  146   a ,  146   b  formed along the internal walls of the bending beams  130   a ,  103   b  to bend the stitch wire  120  about the squared ends of the forming block  132 . In addition to guiding the prongs P, the internal grooves  146   a ,  146   a  provide buckling stability as the prongs P penetrate the collation  12 . 
     In  FIGS. 8   b  and  8   c , the displacement D 2  also causes the forming block  132  (shown in  FIG. 8   b ) to move away, (into or out of the plane of  FIG. 8   c ) such that the web W is free to move upwardly in the subsequent portion of the stroke D 3 . The second portion of the stroke D 2  terminates when the bending beams  130   a ,  130   b  abut the lowermost sheet of the collation  12 . That is, the ends of each of the bending beams  130   a ,  130   b  define a reference surface which will be used by the processor  40  to position the anvil  124  relative to the stitch head  122 . In the final or third portion of the stroke D 3 , a striker or ram  148  (see  FIG. 8   c ) engages the web W of the stitch  120  to drive the prongs P though the collation  12 . At the same time, i.e., while the lower portion of the stitcher  122  moves into position below the collation  12 , the processor  40  issues a fourth signal S 4  to a fourth input actuator  150  to lower the anvil or clincher  124 , (a displacement denoted by line D 4  in  FIGS. 8   c  and  8   d ) against the uppermost sheet of the collation  12 . 
     In  FIG. 8   d , the motion of the striker  148  causes the prongs P to penetrate the collation  12  and crimp/clinch the ends PE of each prong P. In the described embodiment, the clincher  150  includes arcuate surfaces for securing the ends PE of the prongs, however, other clinching devices, including those which actively recurve the ends PE of the prong P, are contemplated. 
     In summary, the various embodiments described herein feature a stitcher/stapler  10  and/or a mailpiece inserter  24  capable of binding multi-sheet collations which vary in thickness. The thickness data/sheet count information  30  may be derived from various sources including a scan code  32 , sheet counter  34 , mail run data file  36  or thickness input device  38 . Throughput is enhanced by arranging the stations  14 ,  16 ,  18  in series and conveying a multi-sheet collation  12  to the apparatus, i.e., the stitcher  20  or stapler  22 , best suited to bind the collation based upon the thickness of the collation  12 . The serial arrangement of the processing stations  16 ,  18  is made possible by a transport and alignment system having alignment mechanisms which may be raised and lowered into and out of idle and active positions, i.e., such that the collation may pass across each of the serial arranged stations  16 ,  18 . Throughput is further enhanced by varying the number of cycles, i.e., oscillations associated with each registration of the registration members  64   a ,  64   b ,  104   a ,  104   b , to align the leading, trailing and side edges  12 L,  12 T,  12 SE of the collation  12 . Finally, the stitcher  20  may also be reconfigured/adapted to vary the size of a binding stitch  120  to bind consecutive variable thickness collations. While prior art stitching apparatus must be adjusted manually to bind collations from one mail run to the next, e.g., stitching collations of a constant thickness for a multi-collation mail run, the stitcher  20  of the present invention is reconfigurable from one collation to the next in the same mail run. As a consequence, the stitcher/stapler  10 , when used in the context of, or in combination with, a mailpiece inserter  24 , is highly robust, adaptable and flexible i.e., in terms of the type and thickness of collations which can be produced. 
     It is to be understood that the present invention is not to be considered as limited to the specific embodiments described above and shown in the accompanying drawings. The illustrations merely show the best mode presently contemplated for carrying out the invention, and which is susceptible to such changes as may be obvious to one skilled in the art. The invention is intended to cover all such variations, modifications and equivalents thereof as may be deemed to be within the scope of the claims appended hereto.