Abstract:
A registration system including both a primary tamping device and a secondary scuffing device. The scuffing device includes a scuffer arm, an extending/retracting device, a drive subsystem, and an engagement control device. In various exemplary embodiments, the secondary scuffing device is retracted. The scuffing device can thus be used, when required, to register a substrate in the process direction and then retracted enabling the side tampers to cross process register the substrates. In various exemplary embodiments, substrates of varying sizes and types can be registered into common sets using the systems and methods of this invention.

Description:
BACKGROUND OF THE INVENTION 
     1. Field of Invention 
     This invention is directed to systems and methods for registering substrates. 
     2. Description of Related Art 
     An important element of an image forming system is the ability to handle large print jobs while maintaining high speed and efficiency. Critical to this capability is proper alignment, or registration, of the substrates, such as for example copy sheets, as the substrates are transported through various image forming and sheet processing functions. Proper registration ensures accurate and high quality during the image forming and sheet processing process. Further, imaging-forming systems may utilize primary and secondary registration systems during the image forming process to keep substrates properly aligned. For example, substrates could be initially registered prior to image transfer and later during the compilation process. 
     In many imaging-forming systems that have handling and compiling systems, such as, for example, printer copiers and the like, trays are often used to compile the sheets, either individually or in stacks. As is well known in the handling and compiling art, tamping systems are commonly utilized to register the sheets in compiler trays. Walls or tamper arms on the sides of the tray can be moved repeatedly and reversibly against one or more sides of an incoming sheet or sets of sheets, thereby achieving proper alignment and square stacking. Once squared, sheet stacks are more accurately manipulated, such as, for example, by stapling or hole-punching, during the finishing stages of the image forming process. 
     Another important element in imaging-forming systems is the capability of handling a variety of substrates. In most conventional systems used for printers, copiers, and facsimile machines, the types of substrates being transported usually do not vary much. Most systems typically encounter only a limited number of different substrate types, such as, for example, A4 or 8.5″×11″ papers. 
     SUMMARY OF THE INVENTION 
     However, the primary registration system often used in many set compiler subsystems cannot be used for certain sheet types or when two or more sheet sizes are used in combination. Further, the ability to use a secondary registration system in combination with the primary registration system is often limited by the paper path architecture and space constraints, which often requires that the secondary registration system get out of the way of the incoming paper between sheets and/or between sets. Subsequently, the paper path is often designed in a way that only a stationary registration system can be used. In addition, using a secondary registration system only when needed can help to reduce it&#39;s wear, extend it&#39;s replacement life and/or allow its design to be made more economical and/or less robust. Also, using a secondary registration device only when needed, when such a secondary device is a friction type device, can help reduce marking and/or smearing of the substrates when it is not used, especially for those substrates that are prone to marking and/or smearing. 
     This invention provides a registration system approach that helps minimize the footprint and help maximize the efficiency of space used in finishing devices, especially in high volume type finishing applications which may or may not have multiple discharge paths. 
     This invention separately provides systems and methods for registering sheets with tampers and a scuffer. 
     In various exemplary embodiments of the system and methods according to this invention, substrates can be registered using a combination of scuffing and tamping, scuffing only, and/or tamping only. For example, substrates can be first scuffed and then tamped, or vice versa. 
     In various exemplary embodiments, the registration system according to this invention includes both a primary tamping device and a secondary scuffing device. In various exemplary embodiments of the systems and methods according to this invention, the secondary scuffing device can be retracted. For example, the scuffing device can be used to register a substrate in the process direction and then retracted enabling the side tampers to cross-process-register the substrates. 
     In various exemplary embodiments of the systems and methods according to this invention, substrates of varying sizes and types can be registered into common sets using the systems and methods of this invention. 
     These and other features and advantages of this invention are described, or are apparent from, the following detailed descriptions of various exemplary embodiments of the systems and methods according to this invention. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Various exemplary embodiments of the invention will be described in detail with reference to the following figures, wherein: 
         FIG. 1  is a block diagram of one exemplary embodiment of an imaging-forming system usable with various exemplary embodiments of the systems and methods according to this invention; 
         FIG. 2  is a block diagram of one exemplary embodiment of a finisher module; 
         FIG. 3  shows in greater detail a first exemplary embodiment of a retractable scuffer registration device according to this invention, where the retractable scuffer registration device has been extended; 
         FIG. 4  shows in greater detail the first exemplary embodiment of the retractable scuffer registration device according to this invention, where the retractable scuffer registration device has been retracted; 
         FIG. 5  is an exploded view showing in greater detail a first exemplary embodiment of the scuffer arm and threaded slide of the first exemplary embodiment of the retractable scuffer registration device according to this invention; 
         FIG. 6  is a front perspective view showing in greater detail the first exemplary embodiment of the scuffer arm and support frame of the first exemplary embodiment of the retractable scuffer registration device according to this invention; 
         FIG. 7  is a bottom perspective view showing in greater detail the first exemplary embodiment of the scuffer arm and support frame of the first exemplary embodiment of the registration device according to this invention; 
         FIG. 8  shows in greater detail one exemplary embodiment of the support frame of the first exemplary embodiment of the retractable scuffer registration device according to this invention; and 
         FIG. 9  is a flowchart outlining one exemplary embodiment of a method for registering a sheet using the registration system. 
     
    
    
     DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS 
     The various exemplary embodiments of the systems and methods according to this invention enable the registration of substrates in an imaging-forming system to be advanced through the use of a registration system. The mechanisms and techniques used in the registration system according to this invention provide a combination of scuffing and tamping. 
     The following detailed description of various exemplary embodiments of the substrate registration systems and methods according to this invention may refer to one specific type of substrate, copy sheets, for the sake of clarity and familiarity. Further, for the sake of clarity and familiarity, this invention may refer to one specific type of imaging-forming device, a copier or printer. However, it should be appreciated that the principles of this invention, as outlined and/or discussed below, can be equally applied to any known or later-developed substrate and/or imaging-forming device, or any other sheet-like substrate handling device, beyond any copy sheets and copiers specifically discussed herein. 
       FIG. 1  is a block diagram of one exemplary embodiment of an imaging-forming system  100  in which a sheet may need to be registered. As shown in  FIG. 1 , the image-forming system  100  includes a sheet feed module  200 , an image output terminal  300  and a finisher module  400 . In addition, the image forming system  100  includes an additional output device module  500  such as a finisher, stacker or other forms of output finishing and or sheet/set handling devices. 
     It should be appreciated that the sheet feed module  200 , the image output terminal  300  and the finisher module  400 , while depicted separately in  FIG. 1 , are not necessarily separate and distinct components. The functions and/or operations of any one or more of these elements may be carried out by a single device, structure, and/or system. Further, it should be appreciated that additional devices, structures and/or systems may be included in the imaging forming system  100 , such as, for example, a sheet preparation module. 
       FIG. 2  illustrates one exemplary embodiment of the finisher module  400 . As shown in  FIG. 2 , the finisher module  400  includes a sheet receiving inlet  402 , a main transport path  404 , a bypass path  408 , a top bypass tray  410 , an optional temporary compiler or sheet buffering station  416 , a compiling platform  414 , retractable scuffing system  420 , a manipulation device  430 , sheet lead edge registration gates  415  and a discharge outlet  412 . A number of pairs of transport nip rollers  406  move the sheets along the main transport path  404 . 
     It should be appreciated that the manipulation device  430  can be any device capable of manipulating a sheet or a set of sheets, including, but not limited to, stapling, punching, stitching, perforating and/or the like. It should be appreciated that the manipulation device  430  may or may not be included in the finisher module  400  and that the location and/or capability of the manipulation device  430  is a design choice and will be obvious to those skilled in the art. 
     In operation, sheets are received from the image output terminal  300  through the sheet receiving inlet  402 . Sheets are transported along the main transport path  404  by the one or more pairs of transport nip rollers  406 . Sheets not compiled into sets can be diverted to the top bypass tray  410  along the bypass path  408 . Otherwise, sheets are transported along the main transport path  404  and are diverted to the compiler platform  414  by an appropriate one of a number of gates  407  that divert the sheets to the compiling platform  414 . In various exemplary embodiments for each sheet, the appropriate gate  407  is selected based on a length of that sheet. 
     Sheets to be compiled are received by the compiling platform  414 . As each sheet is received, the compiling platform  414  registers the sheet laterally and/or along the process direction by using a scuffing system  420  (shown in  FIGS. 3-4  and  6 - 9 ) and/or one or more tamping devices and lead edge registration gates  415 , which are made capable of pivoting and or moving out of the way of the paper to enable the discharge outlet  412 . The compiling platform  414  continues to receive sheets and to register the sheets until the desired number of sheets in a set are received. The compiled and registered set can be manipulated by the manipulation device  430 . Whether manipulated or not, the compiled and registered set of sheets is then output from the finisher module  400  through the discharge outlet  412  or, alternatively, can be dropped to a stacking device positioned below the compiling platform  414 . The compiling platform  414  is then ready to receive the next set of sheets. An optional temporary compiler or bufferring station  416  can be employed to catch and hold one or more of the first sheets of the next set in order to allow the first set to be processed and discharged. This bufferring operation can be used to improve productivity of the device by eliminating longer time gaps between the last and first sheets of adjacent sets. This process is continued until the desired number of sets is compiled, registered and, optionally, manipulated. 
     Registering sheets is accomplished by utilizing the lead edge registration gates  415  and tamping and/or scuffing each sheet as it moves onto the compiling platform  414 . In various exemplary embodiments, as disclosed in a co-pending U.S. patent application Ser. No. 10/604,013, incorporated herein by reference, one or more of the one or more tamping devices used to register the sheets can be integrated into the compiling platform  414 . 
       FIG. 3  shows in greater detail one exemplary embodiment of the scuffing system  420 . As shown in  FIG. 3 , the scuffing system  420  includes a support frame  421 , a scuffer arm  422 , a lead screw  424  and a threaded slide  425  connected to the scuffer arm  422 . One or more friction wheels  429  are attached to the scuffer arm  422 . In  FIG. 3 , the scuffer arm  422  is in the extended position, where the one or more friction wheels  429  are placed opposite a similar number of idler wheels  431  or a platform (not shown) of a fixed assembly  430 .  FIG. 4  shows the exemplary embodiment of the scuffer system  420  of  FIG. 3  with the scuffer arm  422  in a retracted position. 
     As shown in  FIG. 3 , the scuffer arm  422  also includes a drive belt  433  connected to the friction wheels  429 . The scuffing system  420  also includes a drive system  460  comprising a pair of drive motors  461  and  463 , and a first drive transfer system  480  comprising a first drive belt  482  and a second drive belt  484  that connects the first drive motor  461  to the lead screw  424 . A second drive transfer system  470  includes a third belt  472 , a pair of universal joints  474  and  478  and a shaft  476  to connect the second drive motor  463  to the belt  433 . 
     As shown in  FIG. 3 , the scuffing system  420  utilizes the lead screw  424  and the threaded slide  425  to lower the scuffer arm  422  into a scuffing position. In particular, the first motor  461  of the drive system  460  is operated in an extension direction to rotate the belts  482  and  484  of the first drive transfer system  480 . The motor  461  of the first drive transfer system  480 , via a pulley, drives the belt  482  which, by a set of pulleys, is connected to and drives the belt  484 , causing the belt  484  to rotate. The belt  484  is connected to the lead screw  424  by yet another pulley. The rotation of the belt  484  in the extension direction causes the lead screw  424  to rotate in the extension direction. As a result, the threaded slide  425 , which is threaded onto the lead screw  424 , moves to the extended position shown in  FIG. 3  from the retracted position shown in FIG.  4 . As depicted in  FIG. 3 , this in turn extends the scuffer arm  422  in a motion that brings the scuffer arm  422  and the friction wheels  429  towards, and ultimately into contact with, a top surface of a sheet to be scuffed. 
     At the same time, or at some earlier or later time, that the first motor  461  of the drive subsystem  460  is operated in an extension direction, the second motor  463  of the drive system  460  operates to rotate the belt  433  and drive the friction wheels  429 . The motor  463  drives the third belt  472 , which is connected to the first universal joint  474 . The first universal joint  474  is connected to the second universal joint  478  by the shaft  476 , which is held in place by the guiding plate  427  of the support frame  421 . The second universal joint  478  is in turn connected to a drive shaft  434  (shown in  FIG. 5 ) of the scuffer arm  422 . 
     As threaded slide  425  moves from an initial retracted position shown in  FIG. 4  to the extended inclined position shown in  FIG. 3 , the scuffer arm  422  is supported and guided in the manner discussed below. One end portion of the scuffer arm  422  is pivotally connected to the threaded slide  425  via the drive shaft  434 . When the threaded slide  425  moves between the extended position and the retracted position, the scuffer arm  422  pivots about the drive shaft  434 . 
     As the scuffer arm  422  is extended, a sheet to be scuffed is caught between the friction wheels  429  and the idler wheels  431  or platform before the scuffer arm  422  becomes fully extended. The friction wheels  429  thus engage the sheet, and, driven by the second drive motor  463 , the second drive transfer system  470  and the belt  433 , push or scuff the sheet forward as the scuffer arm  422  becomes fully extended. Shortly after, or even as, the scuffer arm  422  reaches its fully extended position, the first drive motor  461  is driven in the opposite, or retraction, direction, to return the scuffer arm  422  to its fully retracted position shown in FIG.  4 . 
     In particular, as the first drive motor  461  is operated to drive the first drive transfer system  480  in the opposite, or retraction, direction, the threaded slide  425  also slides along the lead screw  424  in the opposite, or retraction, direction. As the threaded slide  425  slides in the retraction direction, the scuffer arm  422  is pulled from the extended position to the retracted position. 
       FIGS. 5-8  show the scuffer arm  422  and related portions of the support frame  421  and the second drive transfer system  470  in greater detail. As shown in  FIGS. 3-8 , the scuffer arm  422  also includes a cam portion  438 , which controls the angle of orientation of the scuffer arm  422  as it is extended and retracted. As shown in  FIGS. 5-8 , the cam portion  438  is located on a surface of the scuffer arm  422  opposite the belt  433 . The cam portion  438  includes a recessed, arched surface located on a bottom surface  422   a  of the scuffer arm  422 , as shown in FIG.  8 . As the threaded slide  425  moves between the extended position and the retracted position, the recessed arched portion of the cam portion  438  engages with a roller bearing  439 , which as shown most clearly in  FIG. 7 , is attached to the support frame  421 . Thus, arched surface of the recessed, arched cam portion  438  rolls past the roller bearing  439  to support and guide the scuffer arm  422  as it is being retracted to or extended from the support frame  421 . 
     The roller bearing  439  supports and guides the cam portion  438  as the scuffer arm  422  is extended. The roller bearing  439  also supports and guides the cam portion  438  causing the scuffer arm  422  to rise away from the sheet that has just been scuffed, so that the sheet is not caught between the friction wheels  429  and the idler wheels  431  or platform and brought out of registration. In particular, the friction wheels  429  are rapidly vertically disengaged from the sheet before the scuffer arm  422  is translated horizontally. Because the friction wheels  429  are disengaged from the sheet, the sheet is not inadvertently withdrawn by the friction wheels  429  while the scuffer arm  422  is being withdrawn. 
     It should be appreciated that the shape and design of the first and second universal joints  474  and  478 , the design of the scuffer arm  422 , the contact speed and/or angle of the scuffer arm  422  relative to the sheet, and/or the design of the friction wheels  429  that ensure proper engagement with the sheet for registration are design choices that will be obvious and predicable to those skilled in the art. It should also be appreciated that any other known or later-developed mechanism can be used in place of the lead screw  424  and threaded slide  425  to extend/retract the scuffing arm  422 . It should further be appreciated that any known or later-developed mechanism and the design of the cam portion  438  of the scuffer arm  422 , the roller bearing  439  and the connection of the scuffer arm  422  to the threaded slide  425  can be used to support and guide the scuffer arm  422  from an initial retracted position to an inclined extended position. 
     In operation, a sheet is received by the compiling platform  414  via one of the gates  407 . The scuffing system  420  extends the scuffer arm  422  to scuff the sheet forward to ensure the leading edge of the sheet is aligned with, or registered against the lead edge registration gates  415 , or, optionally, a manipulation device  430  (if provided). The scuffer arm  422  may be raised and retracted, enabling the tampers to be engaged. In general, the scuffing system  420  operates as the sheet registration device in the process direction while the tampers are used for cross-process-direction registration. The process of alternatingly scuffing and tamping to register sheets enables the registration of sheet sets of different sizes. However, it should be appreciated that the combination of scuffing and tamping can be altered and combined in a manner that is suitable to the process desired. 
     In addition to scuffing the sheets to obtain lead edge registration, the scuffing system  420  can also be used to thump sheets and/or sheet sets. Thumping or bumping the set with some vertically directed force may be done to help compress the set being compiled. Thumping is accomplished through a vertical motion of the scuffer arm  422  onto the sheets. Further, the use of thumping can be combined with the scuffing and tamping registration process in a manner suitable to the process desired. In various exemplary embodiments, the scuffer system  420 , utilizing it&#39;s up (retracted) and down (extended) motions and friction wheels  429 , as required, can be used to intermittently thump the sheet or set of sheets. 
     The proper amount of pressure should be applied to the scuffer arm  422  against the sheet to avoid damaging the sheet, for example, by marking or crinkling the sheet. In various exemplary embodiments, maintaining the proper pressure by the scuffer arm  422  on the sheet as the sheet is being scuffed is accomplished by a combination of the design of the scuffer arm  422 , including, for example, the design of the retraction extension mechanisms of the scuffing system  420 , and the design of the compiling platform  414 . For example, the compiling platform  414  may incorporate a depression plate that provides an upward pressure on the sheets that in turn presses up against the scuffer arm  422  while the scuffer arm  422  is in operation. It should be appreciated that the design of the scuffer system  420  and the compiling platform  414  is a design choice and will be obvious and predictable to those skilled in the art. 
       FIG. 9  is a flowchart outlining one exemplary embodiment of a method for registering a sheet according to this invention. Beginning in step S 100 , operation of the method continues to step S 110 , where a current sheet is received by the compiling platform  414 . Then, in step S 120 , a determination is made whether the current sheet needs to be scuffed to properly register the current sheet. If the sheet does require scuffing, operation continues to step S 130 . Otherwise, operation jumps to step S 160 . 
     In step S 130 , the scuffer arm is extended and the friction wheels are driven. Next, in step S 140 , the sheet is scuffed forward by the friction wheels of the scuffer arm to register the lead edge of the current sheet. Then, in step S 150 , friction wheels of the scuffer arm is retracted to disengage the friction wheels from the sheet. Operation then continues to step S 160 . 
     In step S 160 , the scuffer arm is fully retracted. Then, in step S 170 , the sides of the sheet are tamped. Next, in step S 180 , a determination is made whether the sheet is the final sheet of a set. If the sheet is the last sheet of a set or is not in a set, operation continues to step S 190 . Otherwise, operation returns to step S 110 . 
     In step S 190 , a determination is made whether the sheet set requires manipulation. If the set requires manipulation, operation continues to step S 200 . Otherwise, operation jumps to step S 210 . In step S 200 , the set is manipulated. Next, in step S 210 , the set is output to a downstream processing module or operation, or is output to a stacker or other output tray or device. Then, in step S 220 , operation of the method ends. 
     While this invention has been described in conjunction with various exemplary embodiments, it is to be understood that many alternatives, modifications and variations would be apparent to those skilled in the art. Accordingly, the preferred embodiments of this invention, as set forth above are intended to be illustrative, and not limiting. Various changes can be made without departing from the spirit and scope of this invention.