Patent Publication Number: US-8123448-B2

Title: Apparatus and methods for automatically binding a stack of sheets with a nonspiral binding element

Description:
RELATED APPLICATIONS 
     This application claims priority to U.S. Provisional Patent Application Ser. No. 60/708,579 filed on Aug. 16, 2005 and U.S. Provisional Patent Application Ser. No. 60/709,710 filed on Aug. 18, 2005, both of which are incorporated herein by reference. 
    
    
     FIELD OF THE INVENTION 
     The present invention relates generally to binding elements for holding a plurality of perforated sheets or the like, and more specifically to automated processes and machines for handling and binding a plurality of successive perforated sheets into a book. 
     BACKGROUND OF THE INVENTION 
     Typically, mechanically bound books are created using either relatively small, inexpensive machines that require a significant amount of labor to create each book, or large, expensive machines that require much less labor per book. Use of small, inexpensive machines is widespread inasmuch as they are present in many offices. Such machines are adequate for creating relatively small quantities of books, provided the operator has received some training in their use and has sufficient time to devote to the effort of making the books. As the number of books to be assembled increases, however, the manpower required is significant when utilizing such small, inexpensive machines. In practice, it is not uncommon for operators to spend an hour or more assembling twenty to fifty books. 
     Automated machines, on the other hand, are relatively uncommon in offices. Rather, they are most often found in dedicated print shops or binderies. While these machines may be capable of creating the twenty to fifty books in as little as two to five minutes, the size and cost of automated machines can be prohibitive to smaller or occasional users. As a result, these more efficient, automated machines are typically available to only a very small percentage of people who desire mechanically bound books. Further, it is often time consuming for operators to set up such automated machines or to modify machines to change from one size or color of binding element to another. The specialized training required to operate and set-up automated binding machines further limits benefits available to general office users. 
     The preceding two decades have witnessed a dramatic change in the way documents are created and printed, however. The advent and adoption of personal computers and word processing software have greatly increased the user&#39;s options for production of documentation. Significant decreases in the cost of computers and printers, along with significant strides in efficiency and power have allowed nearly anyone the ability to design and print pamphlets, manuals, books, calendars and the like. As the ability to design and print documents has become widespread, the amount of time required to create a document has dropped dramatically. Unfortunately, however, for a majority of the people creating these documents, the ability to do mechanical binding has not improved significantly over the past two decades. 
     The ability to mechanically bind documents has not kept pace with the ability to create, edit and print the documents due in large part to fundamental problems with the currently available binding styles. Various types of binding elements have been utilized to mechanically bind a stack of perforated sheets or the like, including metal spiral wire or plastic spiral, double loop wire, wire comb, or hanger-type designs, plastic comb, hot-knife or cold-knife strip (marketed by the assignee of the present invention as VeloBind®), loose leaf binders, such as 3-ring binders, and other dedicated mechanical binding structures, such as the assignee&#39;s ProClick®. Examples of such binding elements which are of a wire comb or hanger-type design are disclosed, for example, in U.S. Pat. No. 2,112,389 to Trussell and U.S. Pat. Nos. 4,832,370 and 4,873,858 to Jones, while machines for assembling such binders are disclosed in U.S. Pat. No. 4,031,585 to Adams, U.S. Pat. No. 4,398,856 to Archer et al., U.S. Pat. No. 4,525,117 to Jones, U.S. Pat. No. 4,934,890 to Flatt, and U.S. Pat. No. 5,370,489 to Bagroky. Other binding devices are disclosed, for example, in the following references: U.S. Pat. Nos. 2,089,881 and 2,363,848 to Emmer, U.S. Pat. No. 2,435,848 to Schade, U.S. Pat. No. 2,466,451 to Liebman, U.S. Pat. No. 4,607,970 to Heusenkveld, U.S. Pat. No. 4,904,103 to Im, U.S. Pat. No. 5,028,159 to Ammich et al., U.S. Pat. No. 4,369,013, Reexamination Certificate B1 U.S. Pat. Nos. 4,369,013 and Re. 28,202 to Abildgaard et al. Machines for assembling plastic comb or finger binding elements are disclosed in patents such as U.S. Pat. No. 4,645,399 to Scharer, U.S. Pat. No. 4,900,211 to Vercillo, U.S. Pat. No. 5,090,859 to Nanos et al., and U.S. Pat. No. 5,464,312 to Hotkowski et al. Nail-type and VeloBind® elements are disclosed in patents such as U.S. Pat. No. 4,620,724 to Abildgaard et al., and U.S. Pat. Nos. 4,685,700, 4,674,906, and 4,722,626 to Abildgaard. All patents and publications referenced in this disclosure are included herein by reference. 
     Non-spiral binding elements typically include a spine from which a plurality of fingers extends that may be assembled through perforations in a stack of sheets. This spine may be linear, with or without a longitudinally extending hinge. Alternately, the spine may be formed by sequential bending of a wire, as with wire comb or hanger type binding elements. While each of these binding arrangements has its advantages, each suffers from various limitations particular to the type of binding. 
     Due to the structure of such binding devices, which typically include elongated spines and fingers, the binding devices commonly become entangled when stored in a group. Detangling the binding elements in order to assemble and individual element into a stack of sheets or lay the element into a binding machine can be a tedious and potentially time-consuming process. Further, this tendency to become entangled may complicate or prevent the use of such binding devices in automated binding processes or machines wherein an automated feed is desirable. The time required to manually feed binding elements into a machine would be prohibitive to efficient, high-volume automated binding operations. Moreover, maintaining an inventory of such binding elements in an automated machine can require a large volume of space within the machine, necessitating a relatively large footprint. 
     Due to the structure of such binding devices, which typically include predetermined length of fingers for a given binding element, the binding devices are commonly utilized to bind pre-selected thicknesses of stacks of sheets or, alternately, only a limited range of thicknesses of stacks of sheets. As a result, a user that may have the occasion to bind a larger range of stack thicknesses would be required to maintain an inventory of a range of sizes of binding elements. This inventory of various sizes of binding elements may be further multiplied when a user may bind a range of sizes of sheets themselves, i.e., when the stacks of sheets to be bound vary in length. This problem would be compounded in an automated binding process, requiring a large element storage space within the machine and/or frequent element changes within the machine to accommodate varied book sizes. 
     In order to accommodate varying thicknesses of stacks of sheets to be bound, various binding designs have been proposed. U.S. Pat. No. 2,779,987 to Jordan discloses a first strip from which two prongs extend, each of which is received in an opening in a retaining strip, wherein the retaining strip includes a ratcheting structure that secures the prong in position. More commonly used designs typically include a pair of bendable prongs extending from a first strip, which are inserted through openings in the stack of sheets and then into openings in a retaining strip. Each bendable prong is then bent over such that it is disposed substantially adjacent the axis of the retaining strip and then held in position by an interlocking structure or a locking flange or the like, which is slid over the bent end of the prong. Examples of binding structures of this type are disclosed in patents such as the following: U.S. Pat. No. 699,290 to Daniel; U.S. Pat. No. 2,328,416 to Blizard et al.; U.S. Pat. No. 3,224,450 to Whittemore et al.; U.S. Pat. No. 4,070,736 to Land; U.S. Pat. No. 4,121,892 to Nes; U.S. Pat. No. 4,202,645 to Sjöstedt; U.S. Pat. No. 4,288,170 to Barber; U.S. Pat. No. 4,302,123 to Dengler et al.; U.S. Pat. Nos. 4,304,499, 4,453,850, and 4,453,851 to Purcocks; U.S. Pat. No. 4,305,675 to Jacinto; and Great Britain Patent 1,225,120. In such designs, the user can typically reopen the resulting bound structure in order to remove or add further sheets. 
     A more complex design is disclosed in U.S. Pat. No. 3,970,331 to Giulie. The Giulie design is intended for use in libraries or other institutions for replacing the bindings on books or providing permanent bindings on magazines or the like. The binding structure is designed for assembly without the use of expensive machinery for clamping a book together, or the application of heat or mechanical pressure. The Giulie binding structure includes a pair of backing strips that are positioned along opposite sides of the stack of sheets adjacent preformed holes along one edge of the stack. One of the backing strips includes a plurality of studs having ratchet teeth, the other including a series of holes having a mating ratchet tooth. The studs ratchet through the holes, and a blocking means on the receiving strip is generally broken off of the strip and forced into the opening to permanently couple the studs within the openings. The studs may then be broken off or cut off. Thus, a book formed in this manner cannot be opened to edit the contents and then reengaged. Moreover, such a bound book cannot be readily folded back on itself, or lie open in a surface. 
     Such binding elements are not generally adaptable to highly automated binding machines. Automated binding machines require a supply of binding elements be located in or proximal to the device. The greater number of binding elements that can be loaded into a binding element magazine, the longer the machine can run without operator intervention. A smaller the overall size of the magazine, however, theoretically allows the machine to be designed with a smaller physical size. 
     While an element magazine of fifty to one hundred binding elements would seem ideal for general office use, the bulky nature of most currently available binding elements would generally make magazines required to accommodate such a large number of binding elements impractical. Loose-leaf binders, for example, are the poor from this standpoint inasmuch as the integral covers and ring assemblies take up considerable space. Although they can be nested one inside the other, a magazine of considerable length would be required to accommodate fifty to one hundred loose-leaf binders. Even if alternatingly stacked, this requires a considerable volume. For example, fifty binders capable of binding a one-half inch thick document would have a volume of 1700 cubic inches. Similarly, fifty plastic comb, metal spiral, double ring wire or plastic spiral binding elements would each require a volume on the order of 240 cubic inches, respectively, assuming that they are not allowed to mesh within each other and that they are provided to the machine already formed. ProClick® binding elements of the assignee of the present invention, assuming each element is provided to the machine in its open state, would require on the order of 320 cubic inches, while VeloBind®, likewise binding elements of the present assignee, would require on the order of 206 cubic inches. Each of these approximate volumes assumes that the elements are able rest in contact with each other in their most compact organization. Accordingly, these volume estimates do not include any provision for controlling orientation or assisting in delivery to the machine. 
     Packaging binding elements for automation presents significant additional challenges. The durability of the binding element itself may limit the methods by which binding elements are provided to an automated machine. Metal spiral and double loop wire, for example, are constructed of a thin metallic wire, which is relatively easy to deform, either before binding, which will make binding difficult or impossible, or after binding, which may impair page turning or damage the sheets themselves. Inasmuch as metal spiral and double loop wire binding elements are particularly susceptible to damage prior to binding, packaging of the binding element must protect the element for delivery to the binding machine. 
     Alternately, metal spiral and plastic coil elements are more efficient spatially when only the filament is provided to the binding machine and the binding machine itself creates the spiral or coil shape and binds the book. This method is utilized by many binderies in large, automated machines today. For fifty or one hundred elements, however, the space savings of this packaging are more than offset by the space required by the forming mechanism itself. Further, such coil formers introduce additional costs, as well as reliability and operator training issues. 
     When previously formed binding elements are utilized, not only must the element magazine contain a sufficient quantity of binding elements to minimize operator loading, it must support, align and present the binding elements in a form suitable for interaction with the binding machine. Thus, the binding elements must be presented such that the binding machine may remove an element from the magazine and position it in the binding mechanism for interaction with a stack of sheets and before finally finishing the book. The structure of virtually all loose binding elements, i.e. the elongated spine and fingers, makes them highly prone to tangling unless the elements are controlled by the magazine. Even plastic combs, which individually appear generally as a hollow tube with radial slots, sometimes become entangled when the spine of one element slips under the wrapped edge of another. As a result, if the packaging method does not control the elements, the binding machine must have sufficient mechanism to disentangle the elements. Such detangling mechanisms would presumably be prohibitively complex, as well as expensive and unreliable. 
     Large automated machines have attempted to control binding elements to eliminate or minimize tangling in various ways. For example, double loop wire is often formed as a continuous “rope” that is wound around a spool. To prevent entangling on the spool, a strip of paper or other separator material is wound jointly with the element to act as a barrier. This paper strip must be then unwound as the element is used and disposed of by the binding machine. Beyond the fact that the spools tend to be quite large (15-inch diameter spool that is 15 inches wide has a volume of 2650 cubic inches), this method adds cost to the element packaging, creates a waste product and adds an extra step during element changeover. 
     Plastic comb has been automated by attaching the binding elements to a continuous web of fanfold paper using an adhesive, as shown, for example, in U.S. Pat. No. 5,584,633. The machine drives the paper using a tractor feed system and separates individual elements from the paper as needed. In practice, this system can be problematic, however, inasmuch as the adhesive may be sensitive to time and environmental factors. If the adhesive does not adequately retain the elements, the elements will either disconnect from the paper completely, or twist or rotate on the paper, resulting in waste elements and/or causing jams within the binding machine. 
     Plastic coil elements have also been delivered to binding machines in compartmented cartridges that keep each element separated from the others, preventing entangling, as shown, for example, in U.S. Pat. No. 5,669,747. This system typically has the obvious disadvantages of high packaging cost and generally poor packing efficiency. The exception to this general rule has been VeloBind®, which is a two-part binding element structure with plastic male nails from one strip being received in female openings of another strip. VeloBind® has been efficiently packaged in cassettes of one hundred strips (e.g., U.S. Pat. Nos. 4,844,974, 5,051,050, and 5,383,756). While VeloBind® has proven to be a successful packaging and automation solution, a document bound with VeloBind® type elements cannot “lay flat”, i.e., remain opened flat without the user holding the pages. This characteristic limits VeloBind&#39;s® potential with users seeking a pure “lay flat” bound book arrangement. Further, the VeloBind® element does not allow pages to cleanly “wrap around” behind the book after turning, a feature that allows the document to consume less space during use. 
     Dimensional stability of the binding elements themselves also significantly affects automated binding processes. Many mechanical binding styles have inherent manufacturing variations or material properties that make it difficult to automate them successfully. For example, double loop wire consists of a single wire filament formed into a comb pattern. The fingers of the comb are then bent toward the spine to create a “C” profile. The binding process then forces the fingers toward their opposing root on the spine, closing the element and creating a round “O” shape. Since the metallic wire has some inherent elastic properties, the tips of the fingers must be forced past the root some distance in order to ensure the element is closed after spring back. The amount of over-travel necessary to get a correct bind depends on the diameter of the wire, the diameter of the loop, the wire material properties and any work hardening induced on the metallic wire during forming of the “C” shape. Manufacturers of wire binding elements use different brands of wire filament and utilize slightly different profiles for the shape of the loops. Within a given manufacturer&#39;s double loop wire binding elements, standard manufacturing tolerances will also cause enough variation from box to box that the required over-travel is not necessarily consistent. These variations require a binding machine to have an adjustable closing stroke or stop position, not only for size changes, but also for each batch of wire elements. This may be acceptable if the machine is being set up for a long run or an operator is in constant attendance. Unfortunately, however, it is very difficult to create an easy to set up, easy to change, reliable binding machine in view of such variations. 
     Pitch is also a concern with regard to automation of binding processes to provide a bound book with a professional appearance. Pitch is a particular problem with double wire in that the spacing between successive finger loops is not necessarily constant. As the comb shape is formed from a single filament, there is no continuous feature, or spine, on the element that holds each finger in position relative to the next one. The binding machine must then constrain or guide the fingers in order to ensure that they properly line up with the perforations in the sheets to be bound. This is also a problem for metal spiral and plastic coil binding elements. As these elements are, in essence, springs with a low spring constant, the binding machine must control and guide the axial position of the leading point on the element as it is rotated through the document. 
     Plastic coils have an additional disadvantage caused by their material properties. A plastic coil element is generally an extruded vinyl filament that is heated to a softening temperature range and wound around a mandrel before being allowed to cool. This process tends to leave stresses in the binding element similar to that found in injection molded plastic pieces. If the element is subsequently exposed to elevated temperatures, these stresses will cause the element to “relax,” changing the diameter, and, thus, the length of the element. Due to the low melt temperature of vinyl, these elevated temperatures can potentially be encountered during normal transportation, storage and usage. This is particularly problematic in the summer when the elements may be in a truck for several days during the transportation stage. These dimensional changes make feeding the element through the perforations more difficult and can impair the crimping process used to prevent the element from rotating out of the sheets after binding. 
     Thus, each of the binding elements currently known and available in the industry presents certain disadvantages, either in the packaging of the elements prior to binding, the automation of the binding process in connection with the elements, or in the qualities of a book bound by the elements. Even traditional loose-leaf binders are bulky and not readily, compactly packaged. They are cumbersome during use, and take up considerably more space than the documents they enclose. Further, even if the cover of a loose-leaf binder can wrap around behind the binder, the individual pages certainly cannot. 
     SUMMARY OF THE INVENTION 
     Accordingly, it is desirable to create binding elements and moderately priced, user-friendly, reliable mechanical binding machines that will be available other than exclusively to large volume binderies. 
     The invention provides an automated machine for processing a plurality of sheets into a bound book, including a plurality of inventive subassemblies. The machine receives a succession of single sheets from another processing machine, such as a printer or the like. If not yet punched, the machine punches an edge of each sheet before passing the sheets on to a stacker. If necessary, the machine reorients the sheets such that the edge to be punched becomes the leading edge. After punching, the sheet may be redirected so that the unpunched edge becomes the leading edge, depending upon the location of the binding module relative to the tray on which the perforated sheets are stacked. Such a reorientation mechanism is disclosed, for example, in International Application Serial No. PCT/US2006/030542 filed Aug. 4, 2006, and the priority applications thereto, which are hereby incorporated by reference for all matter disclosed therein. 
     Preferably, binding elements of a stack are held in relative positions without the need for a cartridge. Such binding elements are disclosed, for example, in International Application Serial No. PCT/US2005/024620 filed Jul. 12, 2005 and U.S. patent application Ser. No. 11/462,532 filed Aug. 4, 2006, and the priority applications thereto, which are hereby incorporated by reference for all matter disclosed therein. Such binding elements may include an elongated spine, a plurality of fingers extending from the spine, and adhesive on the spine configured to releasably attach the binding elements in the stack to one another and to attach the free ends of the respective fingers to the spine during the binding process. 
     A binding element is separated from the plurality of binding elements by an element feeder. One such appropriate structure for feeding elements includes a vacuum or suction member that initiates a separation of a portion of an element from the stack of elements. The binding element may then be further separated by structure such as a rotary separator and/or a sliding separator to separate the binding element from the stack. The element feeder may then direct the separated element into position for further conveyance, operation, or feeding. Preferably, the element feeder includes structure for retaining the stack of binding elements in a ready position for further feeding, including structure for retaining the last element or backing paper within the machine as the second to the last element or the last element, respectively, is separated. 
     The separated binding element may be further conveyed through the machine by an appropriate clamp, receiving member, or the like. If a flat or generally planar binding element is utilized, a bending and gusseting mechanism may be provided for establishing a bend and a gusset at an appropriate position on the binding element. 
     The fingers of the separated binding element are placed into respective perforations in the stack of perforated sheets. A binding mechanism, or a loop, size, and seal mechanism, then loops the free ends of the fingers around and engages the free ends of the fingers and the spine, such that the adhesive secures the free ends of the fingers to the spine. The bound book is then dropped to an output tray. 
     The design of the binding elements allows the automated binding machine to bind a range of thicknesses of stacks of perforated sheets and provide bound books having a professional appearance with an appropriately-sized binding element. Accordingly, the automated binding machine does not require a large inventory of various sizes of binding elements. Moreover, the automated binding machine requires minimal intervention by a user to bind books, regardless of the size of the stack of perforated sheets. The automated binding machine occupies a relatively small footprint such that it may be utilized in an office atmosphere in conjunction with other processing machines, such as a printer or copier. Should the user not wish to bind a plurality of sheets exiting the processing machine, the automated binding machine may include a bypass path simply to pass the sheets to an output tray or other processing machine. 
     Other features and aspects of the invention will become apparent by consideration of the following detailed description and accompanying drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a schematic view of an automated binding machine of the present invention. 
         FIG. 2   a  is a fragmentary side view of a stacker of  FIG. 1  constructed in accordance with teachings of the invention, and a receiving member coupled to the stacker. 
         FIG. 2   b  is a top view of a stack of perforated sheets configured to be supported in the stacker of  FIG. 2   a.    
         FIG. 2   c  is a partial top view of a stack of perforated sheets, having an alternative configuration of perforations, configured to be supported in the stacker of  FIG. 2   a.    
         FIG. 3  a fragmentary top perspective view of the stacker of  FIG. 2   a , illustrating multiple fingers driven by respective cams. 
         FIGS. 4   a - 4   d  are enlarged fragmentary side views of one of the fingers of the stacker of  FIGS. 2   a  and  3  in four different positions according to the rotational position of the cam driving the finger. 
         FIG. 5  is a fragmentary front perspective view of a binding element feeder of  FIG. 1  constructed in accordance with teachings of the invention, illustrating a stack of binding elements, a suction member, a rotary separator, and a sliding separator configured to separate individual binding elements from the stack of binding elements. 
         FIG. 6  is a fragmentary bottom perspective view of the binding element feeder of  FIG. 5 . 
         FIG. 7   a  is a fragmentary perspective view of the binding element feeder of  FIG. 5 , illustrating the suction member at least partially separating an individual binding element from the stack of binding elements. 
         FIG. 7   b  is a fragmentary perspective view of the binding element feeder of  FIG. 5 , illustrating the rotary separator at least partially separating an individual binding element from the stack of binding elements. 
         FIG. 7   c  is a fragmentary perspective view of the binding element feeder of  FIG. 5 , illustrating the sliding separator at least partially separating an individual binding element from the stack of binding elements. 
         FIG. 8  is a fragmentary side view of the stacker, the receiving member, and the binding element feeder of  FIGS. 2   a  and  3 - 7   c , illustrating additional mechanisms of the automated binding machine including a binding element positioner, a bending and gusseting mechanism, and a binding mechanism constructed in accordance with teachings of the invention. 
         FIG. 9  is a top perspective view of the mechanisms of  FIG. 8 . 
         FIG. 10  is a fragmentary side view of the mechanisms of  FIG. 8 , illustrating an individual binding element positioned in the receiving member and moved toward a stack of perforated sheets supported in the support member. 
         FIG. 11  is a top perspective view of the mechanisms and individual binding element of  FIG. 10 . 
         FIG. 12  is a fragmentary side view of the mechanisms of  FIG. 8 , illustrating the bending and gusseting mechanism forming bends and gussets in the individual binding element positioned in the receiving member. 
         FIG. 13  is a top perspective view of the mechanisms and individual binding element of  FIG. 12 . 
         FIG. 14   a  is a top perspective view of a portion of an individual binding element from the stack of binding elements of  FIG. 5 , illustrating multiple bends and gussets formed in the individual binding element by the bending and gusseting mechanism, and illustrating a free end of a finger of the binding element looped around and secured to a spine of the binding element via adhesive. 
         FIG. 14   b  is a bottom perspective view of the binding element of  FIG. 14   a , illustrating the adhesive configured to secure the free ends of the respective fingers to the spine of the binding element. 
         FIG. 14   c  is a side view of a stack of pre-bent or generally L-shaped binding elements. 
         FIG. 14   d  is a top perspective view of a portion of an individual binding element from the stack of binding elements of  FIG. 5 , illustrating multiple bends and gussets formed in the individual binding element by the bending and gusseting mechanism, and illustrating a free end of a finger of the binding element looped around and secured to a spine of the binding element via a weld. 
         FIG. 14   e  is a top perspective view of a portion of an individual binding element from the stack of binding elements of  FIG. 5 , illustrating multiple bends and gussets formed in the individual binding element by the bending and gusseting mechanism, and illustrating a free end of a finger of the binding element looped around and fastened to a spine of the binding element via a mechanical fastener. 
         FIG. 14   f  is a top perspective view of a portion of an individual binding element from the stack of binding elements of  FIG. 5 , illustrating multiple bends and gussets formed in the individual binding element by the bending and gusseting mechanism, and illustrating a free end of a finger of the binding element looped around and deformably coupled to a spine of the binding element. 
         FIG. 14   g  is a top view of a portion of an individual binding element having an alternatively configured alignment aperture in a first orientation. 
         FIG. 14   h  is a top view of a portion of an individual binding element having an alternatively configured alignment aperture in a second orientation. 
         FIG. 15  is a side view of the binding element of  FIGS. 14   a  and  14   b.    
         FIG. 16  is an enlarged, cross-sectional view of the binding element of  FIGS. 14   a  and  14   b  through line  16 - 16  in  FIG. 14   a.    
         FIG. 17  is a fragmentary side view of the mechanisms of  FIG. 8 , illustrating the individual binding element being inserted through perforations in the stack of perforated sheets. 
         FIG. 18  is a rear perspective view of the binding mechanism, the bending and gusseting mechanism, the receiving member, and a portion of the stacker of  FIG. 17 . 
         FIG. 19  is a fragmentary side view of the mechanisms of  FIG. 8 , illustrating the binding mechanism engaging the respective fingers of the individual binding element to loop the respective fingers around the stack of perforated sheets. 
         FIG. 20  is a rear perspective view of the binding mechanism, the receiving member, and a portion of the stacker of  FIG. 19 . 
         FIG. 21  is a fragmentary side view of the mechanisms of  FIG. 8 , illustrating the binding mechanism in a position such that the free ends of the respective fingers are adjacent the spine of the binding element. 
         FIG. 22  is an enlarged, side view of a portion of the binding mechanism, receiving member, and individual binding element of  FIG. 21 , illustrating the individual binding element binding a relatively large stack of perforated sheets. 
         FIG. 23  is an enlarged, side view of a portion of the binding mechanism, receiving member, and individual binding element of  FIG. 21 , illustrating the individual binding element binding a relatively small stack of perforated sheets. 
         FIG. 24  is a perspective view of a back cover being folded over to cover the spine of the binding element. 
     
    
    
     Before any embodiments 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 arrangement of components set forth in the following description or illustrated in the following drawings. The invention is capable of other embodiments and of being practiced or of being carried out in various ways. Also, it is to be understood that the phraseology and terminology used herein is for the purpose of description and should not be regarded as limiting. The use of “including,” “comprising,” or “having” and variations thereof herein is meant to encompass the items listed thereafter and equivalents thereof as well as additional items. Unless specified or limited otherwise, the terms “mounted,” “connected,” “supported,” and “coupled” and variations thereof are used broadly and encompass both direct and indirect mountings, connections, supports, and couplings. Further, “connected” and “coupled” are not restricted to physical or mechanical connections or couplings. 
     DETAILED DESCRIPTION 
     With reference to  FIG. 1 , a schematic view of an automated processing and binding machine  50  is shown. The processing and binding machine  50  may be coupled to a processing machine  52 , such as a printer, copier, or the like, to receive a plurality of successive sheets directly therefrom for processing into a book. 
     The machine  50  may optionally punch and then bind a series of successive sheets to produce a book with no or minimal operator involvement. To allow the machine  50  to be utilized in a sheet processing system such that the binding operation may be performed on a plurality of sheets or the processes of the machine  50  may be bypassed, a sheet exiting the processing machine  52  along the entry path  54  to the machine  50  may bypass the operations of the machine  50  entirely by proceeding along the exit path  56 . Alternately, the sheet may proceed for further processing by the machine  50  along path  62 . 
     To prepare the sheets for further binding within the machine  50 , the machine includes a punch  64 . A suitable punch  64  is disclosed in greater detail in International Application Serial No. PCT/US2006/030542 filed Aug. 4, 2006, which is incorporated herein in its entirety for everything disclosed therein. The now leading edge of the sheet received at the punch  64  is perforated by the punch  64  and then redirected to path  66  for further processing. As explained in greater detail in International Application Serial No. PCT/US2006/030542, this punch and redirect arrangement allows the punching of consecutive sheets at a very high rate of speed such that the punching operation itself does not slow the flow of sheets through the machine  50 . Moreover, it does not require the rapid accelerations and decelerations typically associated with incheck for end-of-line hyphenline punching arrangements. In the embodiment illustrated herein, the unperforated edge becomes the leading edge as the sheets exit the punch  64 . When utilizing pre-punched sheets, the movement of the die within the punch  64  in the illustrated embodiment may be deactivated, such that the punch  64  is utilized merely to redirect the pre-punched sheets to path  66  such that they are properly presented for the next operation. 
     Alternate punching arrangements may be provided, however. If an in-line or rotary punching arrangement is provided, such as the arrangements disclosed in published U.S. Patent Application Nos. 2005-0081694 A1 or 2005-0039585 A1, which allow the sheet to pass through the punch after or with the punching operation, the perforated edge would lead as the sheet exits the punch. As a result, a redirection module (not shown) would be disposed following the punch such that the unperforated edge of the sheet would proceed along path  66  in the arrangement shown in  FIG. 1 . It should thus be appreciated by those of skill in the art that any combination of punches and/or redirection modules, or neither a punch or redirection module need be provided, so long as the sheets or a stack of sheets are properly presented for binding. 
     With continued reference to  FIG. 1 , to prepare the punched or pre-punched sheets for placement of a binding element, the successive sheets are advanced to a stacker  68 . The sheets proceed along a stacker entry path  70  through feeder  71  by any appropriate method, including, but not limited to one or more driven in-feed rollers  73 , belts, or other arrangement, to be stacked on a support member or a tray  72  (see  FIG. 2   a ). A nip  76  may further be provided along the stacker entry path  70  to provide a desired level of force, or a desired velocity to the sheets as they transition from the stacker entry path  70  to the tray  72 . In the illustrated construction, the nip  76  is formed by one or more pairs of rollers  80 , with the lower roller  80   a  being driven. With continued reference to  FIG. 2   a , one or more static brushes  75  may be coupled to the stacker  68  to eliminate static charge in the sheet prior to the stacking/accumulating of the sheets in the tray  72 . Further, one or more static brushes  75  may be coupled to other portions of the automated binding machine  50 , such as the pivoting clamp  212 , which is described in more detail below. 
     With reference to  FIG. 2   a , the tray  72  may include side flanges  74  to urge the sheets to a central or desired position on the tray  72 . One or more solenoids  77  may be coupled to the side flanges  74  to move the side flanges  74  away or toward each other to facilitate the alignment of the successive sheets as they are stacked on the tray  72  (see also  FIG. 9 ). 
     With reference to  FIG. 2   a , a flange  78 , positioned on either the feeder  71  or the tray  72 , may extend generally normal to the tray  72  for abutting the edge of the stack of perforated sheets to be bound. In the construction of the stacker  68  illustrated in  FIG. 2   a , the flange  78  is positioned on the feeder  71 . 
     In order to urge the proper placement of the sheets on the tray  72 , the stacker  68  may further be provided with a placement element that exerts a downward force on the uppermost sheet of a stack  81  to minimize float and minimize the possibility for entanglement or tie-up with a following sheet that is placed on the stack. The placement element further preferably exerts a pulling force to ensure registration of the sheet against the flange  78 . In the embodiment illustrated, the placement element comprises a plurality of fingers  82  spaced along the length of the sheet, as shown in  FIG. 3 . While the placement element illustrated comprises a plurality of such fingers  82 , it will be appreciated that the placement element could alternately comprise a single structure, so long as the desired placement force is exerted on the individual sheets progressing into the tray  72 . 
     With reference to  FIGS. 3-4   d , the illustrated fingers  82  include an elongated body  84  with an engagement tip  86  and a lower spring element  88 . Movement of the fingers  82  is governed by a pin  90  disposed between the body  84  and the spring element  88 , and a driven camming arrangement including a driven cam  92  disposed within a window  94  formed at the end of the body  84  opposite the tip  86 . As a shaft  96  extending through the cams  92  is rotated, the fingers  82  slide along and pivot about the pin  90  disposed between the elongated body  84  and the lower spring element  88 . 
       FIGS. 4   a - 4   d  illustrate one of the fingers  82  in each of the four relevant positions of the finger  82  as the cam  92  rotates. More specifically, as a sheet advances along the stacker entry path  70  into the tray  72 , the sheet flows over the lowered finger (see  FIG. 4   a ) in position on the top of the stack  81  held in the tray  72 , thus preventing a binding of the newly entering sheet on the sheets already held in the tray  72 . As the sheet enters the tray  72 , the finger  82  pulls back on the sheet presently held on the top of the stack  81 , sliding along the pin  90 , i.e., the finger  82  recesses to the position shown in  FIG. 4   b  as the cam  92  rotates to a forward, upper position (see  FIG. 4   b ). The finger  82  then pivots upward about pin  90  to the position shown in  FIG. 4   c  as the cam  92  continues to rotate to a forward, lowermost position (see  FIG. 4   c ). As the cam  92  continues to rotate to a rearward, lowermost position, the finger  82  is again pushed forward toward to the tray  72  to the position shown in  FIG. 4   d  as the finger  82  slides along the pin  90  (see  FIG. 4   d ). In this way, the tip  86  of the finger  82  is projected above the sheet newly deposited on the stack  81  of sheets supported on the tray  72 . As the cam  92  continues to rotate to the rearward, uppermost position, the finger  82  pivots about the pin  90  and again moves to a lowered, projected position shown in  FIG. 4   a , pressing the newly deposited top sheet into the supported stack  81  of sheets (see again  FIG. 4   a ). As the next sheet moves into position on the top of the stack  81 , the finger  82  pulls back on the top sheet of the stack  81 , urging it to the flange  78 , as the finger movement repeats itself. 
     With reference to  FIGS. 3-4   d , the elongated body  84  of each finger  82  is preferably formed of a relatively rigid material while the lower spring element  88  is formed of a rigid, yet resilient material. In the illustrated construction of the fingers  82 , the body  84  is made from a polymeric material, such as Delrin® available from E.I. du Pont de Nemours and Company, while the spring element  88  is made from a resilient metal (e.g., spring steel) and coupled to the body  84 . Alternatively, the fingers  82  may be unitarily formed of a polymeric material, such as Delrin®, although it may be formed of one or more alternative materials, unitarily, or as separate components. 
     With reference to  FIGS. 3-4   d , one or more of the fingers  82  may further include a friction element  98  to provide increased friction between the fingertip  86  and the sheet disposed along the top of the supported stack of sheets. The friction element  98  may be formed of any appropriate material, such as, for example, polyisoprene, or other rubber, polymer, or foam. In one embodiment, four fingers  82  are provided, two of which include a friction element  98 . The remaining fingers  82  do not include a friction element  98 . Accordingly, the fingers  82  that do not include a friction element  98  do not exert as high of a pulling force on the top sheet, but, rather, act to provide a generally uniform downward force to the stack of sheets to ensure proper positioning of the following sheet to the top of the stack. In other embodiments fewer or more fingers  82  can be used, with any combination including friction elements  98 . 
     In one embodiment, additional devices or elements can be coupled with the stacker  68  to further facilitate proper stacking of the sheets. In one example, a plate can be linked with movement of one or more of the fingers  82  to engage the top sheet over a substantial portion of the surface area. Such a plate can act to tamp or compress the stack  81  to help eliminate air between the sheets. 
     With reference to  FIG. 2   a , the tray  72  pivots about pivot  102  to pivot the tray  72  to a relatively lower position as the size of the stack increases. In order to accommodate varied sizes of supported stacks  81  of sheets, the stacker  68  may further include a sensor  100  or the like to sense automatically the height or the thickness of the stack  81  supported on the tray  72 . With reference to  FIG. 3 , the sensor  100  includes a flag  100   a  disposed along the finger  82  and a sensing beam  100   b . When the finger  82  is in contact with the tray  72  itself, the flag  100   a  blocks the path of the sensing beam  100   b . In operation, as the stack  81  of sheets on the tray  72  becomes thicker, the flag  100   a  eventually no longer blocks the sensing beam  100   b . Thus, when the stack  81  on the tray  72  reaches this predetermined height or thickness, such that the flag  100   a  no longer blocks the path of the sensing beam  100   b , the tray  72  may be automatically lowered by any appropriate mechanism. As the tray  72  is lowered, the position of the finger  82  returns generally to a position wherein the flag  100   a  again blocks the path of the sensing beam  100   b . Similarly, after further movement of the tray  72  during operation of the machine  50 , the sensor  100  identifies and governs the “home” or starting position of the tray  72  such that the tray  72  returns to the “home” position to allow the start of another stacking operation. Additionally, the sensed height or thickness of the supported stack  81  may be utilized in other aspects of the binding process or other machine operation, for example, during the binding element closing operations as will be discussed below. 
     With reference to  FIG. 2   b , a stack  81  of sheets configured to be supported in the tray  72  is shown. A plurality of holes or perforations  218  are punched along respective edges  340  in the individual sheets in the stack  81 , and the perforations  218  in adjacent sheets in the stack  81  are aligned as a result of the operation of the stacker  68  as described above. To facilitate stacking of the perforated sheets and alignment of the perforations  218  in the individual sheets in the stack  81 , the perforations  218  may each include at least partially arcuate longitudinal edges  342  opposite one another generally forming what can be referred to as a “double-D” shaped perforation  218 . As shown in  FIG. 2   b , substantially the entire length of the longitudinal edges  342  is arcuate.  FIG. 2   c  illustrates an alternative construction of the double-D shaped perforation  218   a , including longitudinal edges  342   a  having both arcuate portions  346  and substantially straight portions  350 . As illustrated in  FIG. 2   c , the substantially straight portions  350  are located intermediate the arcuate portions  346  on each of the longitudinal edges  342   a . As a result of the double-D shape of the perforations  218 ,  218   a , individual sheets, as they are being stacked and aligned, are less likely to become caught or hung up in the perforations  218 ,  218   a  of an underlying sheet. 
     With reference to  FIGS. 5 and 6 , once the stack  81  of sheets is complete on the tray  72 , a binding element feeder  110  may insert a binding element  112  into the appropriately aligned perforations  218  in the stack  81  of sheets. It should be appreciated by those of skill in the art that provisions may be made in the machine  50  for manual placement of a pre-punched and aligned stack of sheets by of any appropriate mechanism such as, by way of example only, the tray  72  being supported by a drawer slide. 
     Turning now to the binding element feeder  110 , which is shown generally in  FIG. 1 , and in a more detailed, fragmentary view in  FIGS. 5 and 6 , the binding element feeder  110  provides for uninterrupted binding of stacks of perforated sheets or books without intervention by an operator. Accordingly, the feeder  110  includes a supported supply of binding elements  112 . The illustrated binding elements  112  are disclosed in greater detail in published PCT Patent Application No. WO02006017255 and U.S. patent application Ser. No. 11/462,532 referenced above. In short, the binding elements  112  each include a spine  188  from which a plurality of fingers  210  extend. As described in more detail below, the fingers  210  are the portions of the binding element  112  that are inserted through perforations  218  in the stack  81  of separated sheets, while the spine  188  is the portion of the binding element  112  that is not inserted into the perforations  218 . 
     The spine  188 , the fingers  210 , or both include one or more areas or spots of adhesive  186  for subsequently coupling the distal ends or tips  204  of the fingers  210  to the spine  188  (see  FIG. 14   b ) to form respective loops that are used to bind a stack  81  of perforated sheets. The binding elements  112  are of a relatively thin structure such that they may be disposed adjacent (e.g., where generally planar binding elements  112  are used) or nest with one another (e.g., where generally pre-bent or L-shaped binding elements  112   a  are used, see  FIG. 14   c ) such that the adhesive  186  is also utilized to releasably couple or interconnect the plurality of binding elements  112  together to form a cohesive group, plurality, or a stack that does not require an external cartridge or coupling structure to maintain the relative positions of the elements  112  with respect to one another. Alternatively, the distal ends or the tips  204  of the fingers  210  may be attached to the spine  188  using other methods besides re-using the adhesive  186 . For example, rather than providing the adhesive  186  to attach the fingers  210  to the spine  188  of the binding element  112 , a welding process (e.g., ultrasonic welding, RF-welding, friction welding, and so forth) may be utilized to secure the tips  204  of the fingers  210  to the spine  188  (see weld zone  354  in  FIG. 14   d ). Alternatively, a mechanical fastener  358  (e.g., a rivet) may be utilized to secure the tips  204  of the fingers  210  to the spine  188  (see  FIG. 14   e ). As yet another alternative, the tips  204  of the fingers  210  may be deformably coupled to the spine  188  (see  FIG. 14   f ). In other words, after the tips  204  of the fingers  210  and the spine  188  are brought into contact, a male and female die set may be utilized to permanently deform portions of the fingers  210  and portions of the spine  188 , resulting in a plurality of indentations  362  that secure the tips  204  of the respective fingers  210  to the spine  188 . 
     Inasmuch as the binding elements  112  do not require a cartridge or bulky coupling structure from which the binding elements  112  must be separated, there is virtually no waste from the binding elements  112  within the machine  50 , and no provision or space is required within the machine  50  for collection of waste for later disposal or recycling. Rather, the stack of binding elements  112  may be loaded directly in the feeder  110  as a single unit. Depending upon the structure of the element stack indexer (as will be discussed below), any release paper disposed along the adhesive of the lowermost element  112  may be removed prior to placement of the stack of elements  112  into the machine  50 . To facilitate loading, the binding element feeder  110  or a portion thereof may be disposed on drawer slides or the like, or may be otherwise accessible to allow placement of the supply of binding elements  112  into the machine  50 . Although the particular design of binding element may vary from the illustrated design, the illustrated binding element design provides a large inventory of binding elements  112  in a relatively small volume. For example, rather than providing flat or generally planar binding elements  112  to the binding element feeder  110 , pre-bent or L-shaped binding elements may be used. 
     As shown in  FIG. 5 , the stack of binding elements  112  is supported within the feeder  110  on one or more supports  114 ,  116 . It should be noted that the stack of binding elements  112  may include one or more scallops  118 , channels, bores, or the like for mating receipt of the supports  114 ,  116  to ensure proper placement of the stack of binding elements  112  within the binding element feeder  110 . The binding element feeder  110  may further include structure for advancing the stack of binding elements  112  along the supports  114 ,  116  to place the stack of binding elements  112  in position to present a single binding element  112  for binding into the stack  81  of perforated sheets. In the illustrated embodiment, the structure for advancing the stack of binding elements  112  includes a plurality of rods  122 ,  126  along which a back plate  124  may ride to advance the stack of binding elements  112  forward, although it should be appreciated that the support structure and advancing structure may be of any appropriate design. 
     With reference to  FIGS. 5 and 6 , the feeder  110  also includes an alignment member  119  projecting through respective apertures  121  in the spines  188  of the binding elements  112  (see also  FIGS. 14   a  and  14   b ). Like the supports  114 ,  116 , the alignment member  119  may provide lateral or side-to-side alignment of the stack of binding elements  112  in the feeder mechanism  110  and also prevents a user from improperly loading the binding elements  112  into the feeder mechanism  110  in the wrong orientation. However, the alignment member  119  may also serve as a brand-specific identifier for the automated binding machine  50 . In other words, one brand of automated binding machine  50  may position the alignment member  119  in the location shown in  FIGS. 5 and 6  so that a particular brand or supply of binding elements  112 , which have apertures  121  in corresponding locations, must be utilized. Other brands or supplies of binding elements  112 , having apertures in alternative locations other than that shown in  FIGS. 14   a  and  14   b , would not be usable in the feeder mechanism  110  of  FIGS. 5 and 6  because of the misalignment between the alignment member  119  and the alternative aperture locations in the binding elements  112 . 
     Rather than providing a circular alignment aperture  121  or changing the location of the aperture  121 , the binding element  112  may include an alternatively-configured alignment aperture  366 , such as the triangular alignment aperture  366  illustrated in  FIG. 14   g . The alignment aperture  366  may be configured in any of a number of different ways (e.g., different shapes, different sizes, different orientations such as the orientation of the alignment aperture  366 ′ in  FIG. 14   h ) to serve as a brand-specific identifier of the binding elements  112 . 
     Rather than relocating the alignment member  119 , different configurations (e.g., different shapes, sizes, and orientations) of the alignment member can be used to distinguish between different brands of binding elements  112  (e.g., a triangular cross-sectional shape to receive triangular aperture  366 , see  FIG. 14   g ), and/or the alignment member may be re-oriented to receive brand-specific binding elements  112  (e.g., those binding elements  112  in  FIG. 14   h  having the differently-oriented triangular alignment aperture  366 ′). 
     With reference to  FIG. 5 , in order to separate a forward-most binding element  130  from the stack of binding elements  112 , the binding element feeder  110  includes a separation mechanism having a number of subassemblies. While the separation mechanism is described with regard to these subassemblies, it should be appreciated that the separation mechanism may be alternately structured and include entirely different components, or one or more of the presently described components, alone, or in combination with the structure described herein or other appropriate structure. In the illustrated embodiment, the separation of the forward-most binding element  130  from the stack of binding elements  112  is initiated by a suction subassembly  132 . The suction subassembly  132  includes a suction member or a suction cup  134  through which a vacuum or suction is drawn. With additional reference to  FIG. 7   a , the suction cup  134  is positioned toward the distal end  204  of one of the fingers  210   a  of the binding element  130  toward one end of the binding element  130 , and suction is drawn. The suction cup  134  is pulled away from the stack of binding elements  112 , exerting an outward force on the finger  210   a  of the binding element  130  such that the finger  210   a  of the binding element  130  is bowed away from the stack of binding elements  112 . By way of example only, the initiation of separation may alternatively be accomplished by mechanisms such as an edge pick or friction members. 
     Returning to the illustrated embodiment in  FIGS. 5-7   a , both the movement of the suction cup  134 , and the suction drawn therethrough are governed by a camming mechanism  138 . The camming mechanism  138  includes a cam  140  that rotates about an axis  142 , a cam follower  144 , and a four bar linkage  146  coupled to the rotating cam  140  by an L-shaped linkage  147  at coupling  148 . The movement of the four bar linkage  146  as governed by the rotation of the cam  140  and the movement of the L-shaped linkage  147  governs the movement of the suction cup  134  supported thereon toward, onto, and away from the finger  210   a  of the binding element  130 . The linkage  146  may be seen more clearly in the lower perspective view of  FIG. 6 . Parallel links  150 ,  152  are pivotably secured on ends  154 ,  156 , respectively to the frame or other stationary support member  158 , while the other ends  160 ,  162 , respectively are pivotably coupled to opposite ends of a link  164 . The L-shaped link  147  is pivotably coupled at one end  170   a  to the cam  140  by another link  148 . The apex  174  of the L-shaped linkage  147  is pivotably coupled to the four bar linkage  146  at  162 . The other end  170   b  of the L-shaped link  147  (i.e., at the end of the other leg) is slidably coupled to four bar linkage  146 , the movement of the end  170   b  being governed by a channel  176 . In this way, the movement of the L-shaped link  147  at its apex  174  is governed by the rotation of the cam  140  and the pivoting of parallel links  150 ,  152 . As the cam  140  rotates, the L-shaped link  147  is pivoted toward or away from the finger  210   a  of the binding element  130 . The movement of the end  170 , upon which the suction cup  134  is supported, is additionally governed by the limitations of the channel  176 . It should thus be appreciated by those of skill in the art that the suction cup  134  is advanced toward the finger  210   a  of the binding element  130 , and then dropped down against the surface of the finger  210   a  of the binding element  130 . The suction cup  134  is then lifted away from the stack of binding elements  112  to lift the tip  204  of the finger  210   a  of the binding element  130 . The suction cup  134  is subsequently moved away from the front of the stack of binding elements  112 , the significance of which is described below. 
     The actual suction drawn through the suction cup  134  is likewise governed by the rotation of the cam  140  in the illustrated embodiment. More specifically, the cam follower  144  is coupled to a spring-loaded piston  180  within a cylinder  182 . As the cam  140  rotates, the piston  180  is biased outward from the cylinder  182  as the cam follower  144  follows the peripheral surface of the rotating cam  140 . As the piston  180  moves outward, it draws a vacuum within the cylinder  182 . This vacuum is transmitted to the suction cup  134  by way of a coupling tube  183 . It should be appreciated that the rotation of the cam  140  is timed such that the piston  180  moves outward from the cylinder  182  to draw the vacuum just as the suction cup  134  is placed upon the finger  210   a  of the binding element  130 . In this way, the suction cup  134  remains under suction as it pulls the finger  210   a  of the binding element  130  away from the stack of binding elements  112  for further engagement and separation of the forward-most binding element  130  from the stack of binding elements  112 . It should be appreciated by those of skill in the art that the suction may be developed by an alternative arrangement, such as, for example, a vacuum pump. The illustrated embodiment, however, has the advantage that both the movement of the suction cup  134  and the suction drawn therethrough are governed by a single motor. 
     With reference to  FIGS. 5 ,  6 , and  7   b , once separation of the forward-most binding element  130  is initiated by the finger  210   a  of the binding element  130  being arched away from the stack of binding elements  112 , further separation of the forward-most binding element  130  from the stack of binding elements  112  is provided by a separator  184  that further separates the finger  210   a  of the binding element  130  and a portion of the spine  188  of the forward-most binding element  130  from the stack of binding elements  112 , thus separating at least one spot of adhesive  186  (see  FIG. 14   b ) on the spine  188  of the forward-most binding element  130  from the stack of binding elements  112 . The illustrated separator  184  is in the form of a rotating element or a rotating member from which a plurality of ramped protrusions or projecting edges  190  extend. Specifically, the rotary separator  184  includes four projecting edges  190 , however, any number of projecting edges  190  (e.g., 2, 3, 5, etc.) may be utilized. With reference to  FIG. 7   b , as the rotary separator  184  rotates in a counter-clockwise direction, one of the projecting edges  190  enters the space formed between the finger  210   a  of the binding element  130  and the adjacent stack of binding elements  112 , to separate the end of the spine  188  from the stack of binding elements  112 . It should be appreciated that once the projecting edges  190  of the separator  184  rotates to separate the forward-most binding element  130  from the stack of binding elements  112 , it remains in position adjacent the separated binding element  130  such that it retains the remaining stack of binding elements  112  to the rear. 
     Following this separation, the remaining portion of the spine  188  with its adhesive  186  is separated from the remaining stack of binding elements  112  by a linearly-movable member, or a sliding or a gliding separator  192  that progressively separates the remaining spots of adhesive  186  along the length of the spine  188 . The gliding separator  192  moves from the partially-separated end of the binding element  130  to the opposite end of the binding element  130  to complete the separation of the forward-most binding element  130  from the stack of binding elements  112  (see  FIG. 7   c ). In the illustrated embodiment, the gliding separator  192  is in the form of a movable trolley  194  having one or more ramped separators or projecting edges  196  configured to move between the spine  188  of the forward-most binding element  130  and the remaining stack of binding elements  112 , and progressively separate the same. In the illustrated construction of the separator  192 , two projecting edges  196  are utilized, however, any number of projecting edges  196  (e.g., 3, 4, 5, etc.) may be used by the separator  192 . 
     To retain the stack of binding elements  112  in position during this separation process, a retaining guide (not shown) may be provided at the end of the stack of binding elements  112  opposite the rotating separator  184 . Such a retaining guide may be similar to that shown and described in the previously-referenced U.S. Provisional Patent Application Ser. Nos. 60/708,579 and 60/709,710. As the trolley  194  with the projecting edges  196  moves toward the retaining guide  200 , the retaining guide may be moved out of engagement with the remaining portion of the stack of binding elements  112 . The trolley  194  eventually comes to rest with the projecting edge  196   a  disposed along the end of the stack of binding elements  112  to retain the stack of binding elements  112  in position. Upon eventual return of the trolley  194  to the opposite end of the stack of binding elements  112 , the retaining guide may return to its biased or home position at the end of the stack of binding elements  112  opposite the rotating separator  184 . 
     With reference to  FIGS. 5-7   c , to prevent the now separated forward-most binding element  130  from dropping within the machine  50  due to the force of gravity or from becoming otherwise dislodged, the binding element feeder  110  is further provided with a retaining mechanism. In the illustrated embodiment, the retaining mechanism is in the form of a plurality of fingertip stays  202 . When in position against the tips  204  of the fingers  210  of the binding element  130 , the stays  202  hold the tips  204  of the fingers  210  of the binding element  130  adjacent to the stack of binding elements  112 . The fingertip stays  202  are mounted within the binding element feeder  110  such that they may be moved out of engagement with the binding element  130  and the stack of elements  112  when retention is no longer required. While they may be alternatively mounted, the plurality of stays  202  in the illustrated embodiment are rotatably mounted such that they may be simultaneously rotated out of engagement with the tips  204  of the fingers  210  of the separated binding element  130 . 
     With reference to  FIGS. 5 ,  6 ,  8 , and  9 , to further transmit the now separated forward-most binding element  130  from the remaining stack of binding elements  112 , the binding element feeder  110  further includes an element positioner  206 . While the positioner  206  may be of any appropriate design, the illustrated positioner  206  includes a movable bar  208  from which a plurality of fingers  211  extend. As shown in  FIGS. 8 and 9 , the positioner  206  pushes the separated binding element  130  further from the stack of binding elements  112  and into a position for access by a pivoting receiving member or clamp  212  that further advances the element  130  through the binding process. Once the separated binding element  130  is pushed from the stack of binding elements  112 , the pivoting clamp  212  pivots downward to clamp the spine  188  of the separated binding element  130 . As shown in  FIG. 9 , the pivoting clamp  212  includes a plurality of clamping elements  214  that receive and clamp the spine  188  of the separated binding element  130  between the portions of the spine  188  having the spots of adhesive  186  and between adjacent fingers  210 . The surface of the spine  188  disposed opposite the spots of adhesive  186  are positioned adjacent one or more surfaces  216  along the clamp  212 . The significance of this structure will become apparent upon further explanation. Once the spine  188  of the separated binding element  130  is grasped by the clamp  212 , the finger tip stays  202  are rotated out of engagement such that they no longer support the separated binding element  130 . As with the other components of the binding element feeder  110 , it should be appreciated that the positioner  206  as well as the clamp  212  may be of alternative designs. 
     With reference to  FIGS. 10 and 11 , the pivoting clamp  212  with the separated binding element  130  pivots downward toward the stack  81  of sheets supported on the tray  72 . To properly position and guide the fingers  210  of the separated binding element  130  into the perforations  218  in the stack  81  of sheets, one or more ramped surfaces  220 , including surfaces of the rotated finger tip stays  202 , may be positioned to direct the fingers  210  of the binding element  130 . In the illustrated embodiment, a plurality of arms  222  are additionally provided that pivot outward from the stacker  68  to guide the fingers  210  of the separated binding element  130  into the perforations  218 . 
     In order to obtain a finally bound element that closely resembles a round shape, the separated binding element  130  may be bent and preferably provided with a gusset  130   a  to inhibit the straightening or relaxation of the bent binding element  130  (as shown, for example, in  FIGS. 14   a - 16 ). As shown in  FIG. 1 , the machine  50  may be provided with a bending and gusseting assembly  224 . As best shown in  FIGS. 12 and 13 , the pivoting clamp  212  pivots downwardly to insert the fingers  210  of the separated binding element  130  into the perforations  218 , and to dispose the base  130   b  of the fingers  210  adjacent the bending and gusseting assembly  224 . While inserting the fingers  210  into the perforations  218 , the head of the clamp  212  may rotate to bend the separated binding element  130  near the respective bases  130   b  of the fingers  210 . The bending and gusseting assembly  224  further preferably includes a plurality of male dies  230  secured to the head of the pivoting clamp  212 , and a plurality of mating female dies  232  slidably coupled to a frame of the gusseting assembly  224  (see  FIGS. 12 and 13 ). The female dies  232  include a pair of pins disposed on slides  238 . In operation, the slides  238  move forward toward the male dies  230  to plastically deform the separated binding element  130  to form gussets  130   a  at the bend in the base  130   b  of the fingers  210 . It should be appreciated, however, that the bending and gusseting operations may alternatively be performed simultaneously. The fingers  210  may be bent to a relatively sharp angle, for example, to angles ranging from less than 90° to approximately 120° relative to the spine  188 , such that the sharp corner will be maintained regardless of springback or relaxation. 
     With reference to  FIGS. 17 and 18 , with the fingers  210  bent at their respective bases  130   b , the pivoting clamp  212  continues to move downward to complete the insertion of the fingers  210  into the perforations  218  in the stack  81  of sheets. As the pivoting clamp  212  moves toward the tray  72 , the pivoting clamp  212  and tray  72  continue to pivot downward toward a closure or loop, size and seal mechanism or a binding mechanism  240  (see also  FIG. 1 ). As the tray  72  approaches the binding mechanism  240 , the cam followers  242  ride along a lower surface of the tray  72  to cause the mechanism  240  to begin to rotate about a pivot point  244 . As the binding element  130  approaches the mechanism  240 , the fingers  210  of the binding element  130  slide along a plurality of parallel surfaces  243  of a flexible sealing bracket  246  as the mechanism  240  pivots, causing the fingers  210  to loop as they slide (see  FIGS. 19 and 20 ). As the fingers  210  slide along the surfaces  243 , they are guided by guides  250 , the finger tips  204  continuing to slide along the surfaces  243  until such time as the tips  204  abut tip stops  252  disposed toward the ends of the surfaces  243 . In this way, the tip stops  252  prevent the tips  204  from sliding further along the surfaces  243  as the mechanism  240  loops the tips  204  toward the spine  188 . 
     With reference to  FIGS. 21-23 , according to one embodiment, the tip stops  252  are spring biased by spring steel  253 . As a result, as the flexible sealing bracket  246 , with the fingers  210  disposed on the surfaces  243 , approaches the male die plate  230  as shown in  FIG. 22 , the fingertip stops  252  retract into the respective surfaces  243  as the surfaces  243  continue to move toward the spine  188  of the binding element  130 . In this way, the surfaces  243  press the fingers  210  against the adhesive  186  positioned along spine  188  to couple the fingers  210  to the spine  188  to complete the book. The mechanism  240  is subsequently rotated back to its initial position and the clamp  212  is pivoted upwardly to receive another binding element  112 . 
     In order to provide quality binding of different heights or thicknesses of stacks  81  of sheets, the binding mechanism  240  forms a smaller or larger loop (i.e., an appropriately-sized loop) based upon the height or thickness of the stack of sheets  81 . This can be referred to as dynamic sizing. It should be appreciated by those of skill in the art that the relative position of the pivot point  244  of the binding mechanism  240  (as determined by the pivot shaft  245 , see  FIGS. 18 and 20 ) to the tray  72  determines the position at which the binding element fingers  210  will be positioned along the adhesive  186  on the spine  188 . While the relative positions may be determined by any appropriate arrangement, in one embodiment, movement of the tray  72  as a stack  81  of sheets is formed thereon is sensed by the sensor  100  and transmitted to the binding mechanism  240  via a gearing mechanism, which positions the mechanism  240  relative to the tray  72  to provide appropriately-sized loops of the binding element fingers  210  and sealing pressure during placement of the fingers  210  along the adhesive  186  on the spine  188 . As shown in  FIG. 23 , when a small-sized stack  81  of sheets is bound, the fingertip stop  252  may extend entirely beyond the male die plate  230  of the pivoting clamp  212 . This is the result of the fingers  210  in the binding element  130  forming a smaller loop to accommodate the thinner stack  81  of sheets, such that the tips  204  of the respective fingers  210  are spaced further from the spine  188  of the binding element  130 . Because the same binding element  130  may be configured, during the dynamic sizing process described above, to form relatively large loops (see  FIG. 22 ) or relatively small loops (see  FIG. 23 ), any of a number of different appropriately-sized loops may be formed by the binding element  130  to accommodate a wide range of thicknesses of the stack  81  of perforated sheets. It should be appreciated that alternative arrangements may be provided for establishing the relative positions of the tray  72 , pivoting clamp  212 , and binding mechanism  240 , and for providing an appropriate loop, size and seal. 
     Once the stack  81  of sheets is bound, the binding mechanism  240  is rotated out of engagement and the pivoting clamp  212  disengages and pivots away from the bound book. Returning to  FIG. 1 , the bound book then drops due to the force of gravity to a rotatably mounted foam covered wheel  260 . As the wheel  260  rotates, the bound book passes through a nip  262  formed with a plate  264  and is deposited in a spring-loaded tray  266  within an output bin  268 . In other embodiments, the tray  266  may be static or stationary instead of spring-loaded. In other embodiments, the tray  266  may be actively driven by an electric motor or similar arrangement to lower as the number of bound books supported on the tray  266  increases. Preferably, the tray  266  or the tray  266  and bin  268  are disposed within a drawer type of arrangement such that it/they may be pulled out from the machine  50  for easy access and removal of the bound books. It should be appreciated that the book stacking arrangement may include alternative structure(s). For example, the wheel  260  may be driven, or merely require a small amount of force to provide rotation. Alternatively, a funnel or a series baffles may be provided to place the bound book for stacking and removal. Bound books could also exit via a conveyor or a pusher mechanism. 
     With reference to  FIGS. 22 and 23 , a back cover  272  is positioned beneath the stack  81  of perforated sheets on the tray  72 . The back cover  272  includes perforations  218  substantially similar to the perforations in the stack  81  of sheets, such that the perforations  218  in the back cover  272  are aligned with the perforations  218  in the stack  81  of sheets. With reference to  FIG. 24 , after the bound stack  81  of sheets is dropped into the bin  268 , the back cover  272  is manually flipped over to sandwich the spine  188  and the tips  204  of the respective fingers  210  between the stack  81  of perforated sheets and the back cover  272 . As such, the spine  188  and the tips  204  of the respective fingers  210  are hidden from view when the bound stack  81  of perforated sheets is handled by a reader. 
     It should be appreciated by those of skill in the art that the modules and subassemblies within the machine  50 , as well as the particular design of the binding elements themselves, may be of an alternative configuration than those disclosed in the illustrations herein. While this invention has been described with an emphasis upon preferred embodiments, variations of the preferred embodiments can be used, and it is intended that the invention can be practiced otherwise than as specifically described herein. Accordingly, this invention includes all modifications encompassed within the spirit and scope of the invention as defined by the following claims. For example, various aspects of the invention may be practiced simultaneously. All of the references cited herein, including patents, patent applications, and publications, are hereby incorporated in their entireties by reference. 
     Various features of the invention are set forth in the following claims.