Abstract:
A document system and method of moving documents of a stack. The system operates to move documents by rotating a feed wheel and a transport wheel to move a document in a feed direction. The space between documents is maintained by controlling the speed of the feed wheel and the transport wheel independently.

Description:
FIELD OF INVENTION 
       [0001]    The present invention relates to document and sheet feeding devices generally, and more particularly to document and sheet feeding devices that are capable of continuously feeding sheets to be sorted and further processed at high speeds, and more particularly still to a sheet feeding system and method for improving the speed and efficiency of such system by enabling more precise spacing between individual sheets in a set and between separate sets. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0002]    The present invention will be more fully understood from the detailed description and the accompanying drawings, wherein: 
           [0003]      FIG. 1  is a block diagram illustrating a document feeder control system in accordance with the present invention. 
           [0004]      FIG. 2  is a perspective top view photograph illustrating the position of the feed and leading edge sensors on the feed track in accordance with the present invention. 
           [0005]      FIG. 3  is a perspective top view photograph illustrating the servo controllers of the present invention. 
           [0006]      FIG. 4  is a chart summarizing the preferred paper travel speed ranges of the document feeder control system of the present invention. 
           [0007]      FIG. 5  is a flowchart illustrating the steps in initializing the document feeder control system of the present invention. 
           [0008]      FIG. 6  is a flowchart illustrating the post initialization steps in the document feeder control system of the present invention. 
           [0009]      FIG. 7  is a flowchart illustrating the next steps in the document feeder control system of the present invention. 
           [0010]      FIG. 8  is a flowchart illustrating the next steps in the document feeder control system of the present invention. 
           [0011]      FIG. 9  is a flowchart illustrating the next steps in the document feeder control system of the present invention. 
           [0012]      FIG. 10  is a diagrammatic illustration of the system at the time of initial power up. 
           [0013]      FIG. 11  is a diagrammatic illustration of the system at the time of initialization. 
           [0014]      FIG. 12  is a diagrammatic illustration of the system upon pre-feeding the paper sheets at speed  1 . 
           [0015]      FIG. 13  is a diagrammatic illustration of the system at the time of pre-feeding at speed  2 . 
           [0016]      FIG. 14  is a diagrammatic illustration of the system at the time of pre-feeding at speed  2  illustrating the separation between fed pages. 
           [0017]      FIG. 15  is a diagrammatic illustration of the system with servo controller  2  at speed  3  and servo controller  1  at speed  1 . 
           [0018]      FIG. 16  is a diagrammatic illustration of the system with servo controller  2  at speed  3  and servo controller  1  at speed  1 , with the paper being fed through the second set of transport wheels. 
           [0019]      FIG. 17  is a diagrammatic illustration of the system with the feed wheel pre-feeding at speed  3 . 
           [0020]      FIG. 18  is a diagrammatic illustration of the system at the time of initialization again. 
           [0021]      FIG. 19  is a diagrammatic illustration of the system at the time of pre-feeding at speed  1 , and W=2. 
           [0022]      FIG. 20  is a diagrammatic illustration of the system changing to speed  2 . 
           [0023]      FIG. 21  is a diagrammatic illustration of the system at speed  2 . 
           [0024]      FIG. 22  is a diagrammatic illustration of the system at speed  2 . 
           [0025]      FIG. 23  is a diagrammatic illustration of the system changed back to speed  1 . 
           [0026]      FIG. 24  is a diagrammatic illustration of the system back at speed  1 . 
           [0027]      FIG. 25  is a diagrammatic illustration of the system as it changes to speed  2  again. 
           [0028]      FIG. 26  is a diagrammatic illustration of the system at speed  2 . 
           [0029]      FIG. 27  is a diagrammatic illustration of the system with servo controller  2  at speed  3  and servo controller  1  at speed  1 . 
           [0030]      FIG. 28  is a diagrammatic illustration of the system with servo controller  2  at speed  3  and servo controller  1  at speed  1 . 
           [0031]      FIG. 29  is a diagrammatic illustration illustrating servo controller  2  at speed  3 . 
           [0032]      FIG. 30  is a diagrammatic illustration servo controller  2  at speed  3 . 
           [0033]      FIG. 31  is a diagrammatic illustration of the system at the time of completion of a sheet set. 
           [0034]      FIG. 32  is a diagrammatic illustration of the system set ready to initiate accumulation of the next sheet set. 
           [0035]      FIG. 33  is a diagrammatic illustration of a prior art sheet feeder system. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0036]    The following detailed description is of the best mode or modes of the invention presently contemplated. Such description is not intended to be understood in a limiting sense, but to be an example of the invention presented solely for illustration thereof, and by reference to which in connection with the following description and the accompanying drawings one skilled in the art may be advised of the advantages and construction of the invention. 
         [0037]      FIG. 1  illustrates a diagrammatic view of a document feeder control system  10  adapted for use in accordance with the present invention. A stack of sheets or documents  14  to be fed or pulled in a feed direction indicated by arrow  15  is provided in close proximity to a feed wheel  18 . Feed wheel  18  is preferably of a known type comprising a rotatable shaft having a plurality of rollers secured to the shaft, at least one of which rollers is in contact with, or which can be brought into contact with, bottom sheet or document  16  in stack of sheets or documents  14 , such that when the feed wheel  18  is rotated it grips and pulls, or provides a feeding force, on sheet or document  16  in the feed direction  15 . It will be understood that such feed mechanism is merely exemplary, and that depending upon the application, different types of feed mechanisms may be employed while still falling within the intended scope of the present invention. Also shown in  FIG. 1  is a mechanism for further transporting sheets or documents  16  in feed direction  15  comprising a pair of transport wheels  24  and  32 , which wheels are similar to feed wheel  18  in that they are preferably comprised of a shaft having a plurality of rollers secured to the shaft which when the shaft is rotated grip and pull, or provide a feeding force, on a sheet or document  16  in the feed direction  15 . See also  FIG. 2 . It will be understood, however, that depending upon the application, a greater number of such shafts may be provided as part of the conveying mechanism, which shafts are also preferably joined together by O-ring belts  25  or the like secured to pulleys and extending between the rotatable shafts so that the rotation speed of wheels  24  and  32  is the same. At least one of such rotatable shafts is a drive shaft, and idler or guide rollers  27  are positioned adjacent wheels  24  and  32  such that sheets  16  fed by feed wheel  18  in feed direction  15  are received between transport wheels  24  and  32  and rollers  27  and transported to a downstream accumulation area or accumulator  29 , after which each set or stack of sheets is further processed depending on the intended application by various of folding, stacking, mailing, or other mechanized processing equipment available in the prior art. As will be explained in detail below, the speed and accuracy of the feeding process by which sheets or documents  16  in stack  14  are conveyed along the feeding track by the feed wheel  18  and transport wheels  24  and  32  to accumulation area  29  and arranged in separate stacks for further processing by the sheet feeding system of the present invention. 
         [0038]    As illustrated in  FIGS. 3 and 10 , feed wheel  18  is operably connected to a servo controller and servomotor  20 , also referred to herein as “Servo #2,” that drives and controls the activation and deactivation and rotation speed of feed wheel  18 , as controlled by the overall sheet feeder control system which includes a central processing unit (CPU) and RAM and ROM memory and which is implemented using software and/or hardware techniques known in the art. As shown in  FIG. 2  and referred to in subsequent flowcharts and diagrammatic figures, downstream from feed wheel  18  is a first electronic document sensor  22 , also known as the feed sensor and referred to herein as “Sensor A”, which detects the presence or absence of a sheet or document  16  as it is being fed in feed direction  15  and upon reaching or passing such sensor  22 . “Sensor A”  22  may advantageously be an optical sensor of a type that should be known to those skilled in the art and generates an output signal whenever a sheet or document interrupts or is detected to be passing in the path of the sensor; however, “Sensor A”  22  may also be another type of sensor such as an ultrasonic sensor. Transport wheel  24  is situated directly downstream of “Sensor A”  22 , and as indicated above, transport wheel  24  is connected to another transport wheel  32  further downstream by belt  25 . Transport wheels  24  and  32  are operably connected to another servo controller and associated servomotor  26  (see  FIG. 3 ) which is part of the overall feeder control system  10  and is referred to alternatively herein as “Servo #1.” As described below, depending upon the feed conditions the output signal of Sensor A may be used to control and adjust the rotation speed of Servo #1 or Servo #2, or both Servos #1 and 2 simultaneously. 
         [0039]    Encoder  28  is operably connected to the shaft of transport wheel  24 , and is used to measure the length of each sheet or document  16  being fed. Encoder  28  may be a standard shaft encoder with 600 pulse per revolution or other rotary pulse generator. A second electronic document sensor  30 , also referred to herein as leading edge sensor or “Sensor B”, is situated on the downstream side of transport wheel  24 , between transport wheels  24  and  32 . Similar to “Sensor A”  22 , “Sensor B”  30  is also advantageously an optical sensor that generates an output signal whenever a document is detected to be passing in the path of the sensor, but may be another type of sensor such as an ultrasonic sensor. Sensor B  30  is operably connected to encoder  28  such that the output signal of Sensor B activates encoder  28  to perform various functions such as resetting the encoder value to zero, initiating sheet measurement, and performing a check of the calculated encoder value. As explained in greater detail below, the combination of leading edge sensor  30  and encoder  28  connected to transport wheel  24  exactly measures the length of each sheet  16  as it is fed by the feeder, which information is used to configure the system to provide the desired separation between consecutive sheets being fed. 
         [0040]    Transport wheel  32  carries sheets or documents  16  passed from transport wheel  24  to an accumulation area or accumulator  29 , where a plurality of individual sheets or documents  16  intended to be grouped into a set or stack  36  is accumulated prior to be fed further down the feed track for further processing such as to a folding device for folding, and then to an enveloping machine and/or other processing apparatus in a manner known to those skilled in the art. Once a set has been accumulated, the next set to be accumulated is signaled or initiated. 
         [0041]    A preferred manner of operation of system  10  will now be described with reference to the detailed steps in the flowcharts of  FIGS. 5 through 9 , as well as the sequential diagrams shown in  FIGS. 10 through 33 . In each of  FIGS. 10  through  32 , the presence or lack of arrow depictions in the feed and transport roller wheel drawings is indicative of whether or not such wheels are rotating and the direction of such rotation. Referring to  FIG. 5 , in Step  100 , the system  10  is set or initialized in the manner now described. In Step  110  Servo #2 (or feed wheel servo controller  20 ) is activated at Speed #3, causing feed wheel  18  to rotate at a pre-set speed and in turn causing a sheet  16  to be fed, or pre-fed, from the bottom of the stack of sheets  14  in a feeding direction  15 . This is illustrated in  FIG. 11 , in which only the feed wheel is shown rotating, in a clockwise direction. The distance sheet  16  is pre-fed in feeding direction  15  is determined in Step  120 . More particularly, sheet  16  is pre-fed until it is detected by first electronic document sensor (Sensor A)  22 . When “Sensor A”  22  detects sheet  16 , feed wheel servo  20  (Servo #2) stops, causing feed wheel  18  to stop rotating (Step  130 ). Sensor A thus provides a fixed pre-feed point or starting point for sheet or document  16 , which point is also referred to herein as “Alignment Point X”, and also is the alignment point for successive documents or sheets in the same set and additional sets. The starting point is mechanically adjustable according to the position of Sensor A. 
         [0042]      FIG. 4  is a Servo Motor Speed Chart which summarizes the different speeds of Servo #1 and Servo #2, which are indicative of the rotation speeds of feed wheel  18  and transport wheels  24  and  32 , respectively, in accordance with a preferred embodiment of the present invention. Speed #3 referred to above with respect to the speed of Servo #2 is a preferred paper feed speed available to Servo #2 and feed roller  18 . More particularly, transport roller servo  26  (Servo Motor #1) has two available speeds; Speed #1 in which transport wheel or roller  24  has a paper travel speed of between 150-250 inches per second (ips), and Speed #2 in which the paper travel speed is greater than Speed #1 by 2.5-10%. In addition, feed roller servo  20  (Servo Motor #2) has three available speeds; Speed #1 in which the paper travel speed of feed wheel  18  is equal to between 150-250 inches per second (ips), Speed #2 in which the paper travel speed is less than Speed #1 by 2.5-10%, and Speed #3 in which the paper travel speed is less than Speed #1 by 75-90%. By varying such speeds in the manner described, the overall speed of feed system  10  is improved. 
         [0043]    Referring again to  FIG. 5 , when in Step  130  the leading edge of sheet  16  is detected by first electronic document sensor (Sensor A)  22  and Servo #2 is stopped, as part of the pre-feed routine of the first page of the sheet set (Step  140 ), servo controllers  20  and  26  (Servo #1 and Servo #2) are both activated at Speed #1 (Step  150 ), which speeds are preferably the same, so that feed wheel  18  and transport wheels  24  and  32  are rotating at the same inches per second (ips) speed. Step  150  is illustrated diagrammatically in  FIG. 12 , in which both the feed and transport rollers are moving at Speed #1, causing first sheet  16  to be pre-fed forwardly in feed direction  15  until, as shown in  FIG. 13 , the leading edge of the first sheet  16  is detected by second electronic document sensor (Sensor B)  30  (Step  160 ). Once second electronic document sensor (Sensor B)  30  detects or is blocked by first sheet  16 , in Step  170  the value of encoder  28  is reset to zero, and the encoder  28  begins measuring the length of sheet  16 . In addition, in Step  180  a read logic circuit is initialized to enable a scanner to read a visual code, such as a bar code, on the document or sheet  16  if present. 
         [0044]    Referring now to  FIG. 6 , the value measured by encoder  28  is then compared with a preset value (Step  200 ), which preset value is also described herein as “Separation Point Y.” If the value measured by encoder  28  is above the preset value or “Separation Point Y,” in Step  210  the speed of feed roller servo controller (Servo #2) 20 is reduced to from Speed #1 to Speed #3, which reduces the speed of feed wheel or roller  18  to 75-90% of Speed #1. The speed of transport roller Servo #1 is increased from Speed #1 to fastest Speed #2. Alternatively, the speed of transport roller Servo #1 may remain at Speed #1. Since transport wheel  24  is moving at Speed #2 or Speed #1 and feed wheel  18  is now moving at significantly slower Speed #3, as illustrated in  FIGS. 15 and 16  sheet  16   a  in contact with transport roller  24  is being conveyed in the feeding direction  15  at a faster rate than new sheet  16   b  is being fed by feed roller  18 , creating a gap  31  between such consecutive sheets having a predetermined width. Due to this speed change and the difference in speed of the feed and transport rollers, as shown in comparing  FIGS. 15 and 16  the gap between sheets  16   a  and  16   b  has increased in  FIG. 16  as compared to the early time shown in  FIG. 15 . It should be evident to those skilled in the art that the width of gap  31  or “Separation Point Y” as defined by encoder  28  may be selectively configured or controlled by system  10  to provide a desired separation between sheets. As sheet or document  16  is further conveyed in feeding direction  15  with time by transport wheels  24  and  32 , eventually sheet  16  is no longer blocking Sensor A (Step  220 ), at which time if the speed of Servo #1 is Speed #2, the speed of Servo #1 controlling the speed of transport wheels  24  and  32  is reduced from Speed #2 to Speed #1 (Step  230 ). Movement of transport wheel  24  at a reduced speed due to the decreased speed of Servo #1, while at the same time feeder wheel  18  is rotating at an even further reduced speed (Speed #3) as controlled by Servo #2 and is initiating feeding of a second sheet, allows for precision separation between sheets in a set to be achieved by the feeder system  10 , which allows the overall speed of the feeding process to be optimized. 
         [0045]    Once the speed of Servo #1 has been reduced from Speed #2 to Speed #1 in Step  230  as triggered by the unblocking of Sensor A in Step  220 , in Step  240 , if the value measured by encoder  28  is below a preset value, encoder  28  continues measuring. However, once the value measured by encoder  28  is at or above such pre-set value, which is also referred to as “Stop Point Z,” in Step  250  Servo #1  26  is stopped, stopping transport wheels  24  and  32 . Feed wheel  18  continues to rotate, however, and a second sheet or document  16   b  is conveyed by feed wheel  18  from stack  14  in feed direction  15 , until it is blocking Sensor A or “Alignment Point X” (Step  260 ), which triggers Servo #2 and feed wheel  18  to stop again (Step  270 ), similar to Steps  120  and  130  described above. This is illustrated diagrammatically in  FIG. 17 , where Servo #1 has stopped transport wheels  24  and  32  as well as sheet  16   a  are not moving, and in addition new sheet  16   b  has been pre-fed at Speed #3 to Sensor A or Alignment Point X, which as shown in  FIG. 18  causes Servo #2 and feed wheel  18  to also stop, completing initialization of the system  10 . Alignment Point X thus serves the important function of providing a predicable starting or alignment point for sheets being fed by the feeder system  10 . 
         [0046]    Referring next to  FIG. 7 , in Step  310  the system has now been initialized and is waiting for a start signal, illustrated diagrammatically in  FIG. 18 . As used herein Set Count “W” refers to the desired number of sheets to be collected into a group from either a fixed sheet count that has been pre-set by the operator using an input device of a type known to those skilled in the art, or a variable count based on visual code information that is printed on the sheets. In Step  320 , the sheet Set Count that is expected for the sets of sheets is input into the system, and in Step  330 , both transport roller Servo #1 and feed roller Servo #2 are activated at Speed #1. This is also illustrated diagrammatically in  FIG. 19 , in which for exemplary purposes the Set Count W is indicating as equaling two sheets (W=2). 
         [0047]    Second sheet or document  16   b  is fed by the rollers in the feed direction  15  until Sensor B is blocked by the sheet (see  FIG. 20 ), which causes encoder  28  to reset to zero and initiates measuring of sheet  16   b  (Step  350 ). In addition, in Step  360  a read logic circuit is initialized to enable a scanner device to read any visual coded information on the sheet or document, such as a bar code, being fed in the case of a variable sheet count. Encoder  28  continues measuring the sheet or document until in Step  370  the value measured by encoder  28  is at or above Separation Point Y, after which in Step  380  the speed of transport roller Servo #1 is increased from Speed #1 to fastest Speed #2, shown in  FIG. 21 , and in addition the speed of Servo #2 and feed rollers  24  and  32  is simultaneously decreased from Speed #1 to Speed #2. The speed change is initiated when sheet or document  16   b  is no longer being gripped by feed wheel  18 , as is indicated diagrammatically by comparing  FIGS. 19 and 20 . This change in speed of Servo #1 to a faster speed and Servo #2 to a slower speed allows for a controlled separation of the sheets during processing. The increase in such gap with time is evidenced in  FIG. 22 , where a more substantial gap is shown between sheet or document  16   b  held by transport roller  24  and sheet or document  16   c  held by feed wheel  18  as compared to the slightly earlier arrangement shown in  FIG. 21 . Then, in Step  390 , sheet Set Count “W” is incremented to the next number according to the count of sheets to be included in the set. 
         [0048]    Referring now to  FIG. 8 , in Step  410  if the sheet Set Count “W” is complete, the system proceeds as described in Steps  510 - 570  shown in  FIG. 9  and discussed in detail below. If set Sheet Count “W” is not complete, then as shown in  FIG. 8  system  10  monitors whether or not Sensor A is unblocked (Step  420 ). If yes, which arrangement is illustrated diagrammatically in  FIG. 23 , then in Step  430  the speed of Servo #1 is decreased back to Speed #1 and the speed of Servo #2 is increased to Speed #1, so that the rotation speeds of feed wheel  18  and transport wheels  24  and  32  are equal again. Once the speeds are adjusted, in Step  440  and the system checks again if Sensor B is unblocked by document or sheet  16   b , and when Sensor B is unblocked (see  FIG. 23 ), in Step  450  the value calculated by encoder  28  is checked by the system to see if the total length of the sheet is correct. If yes, in Step  460 , the visual code data on a sheet, if any, is checked to see if any set errors occurred. If the total length is correct and no visual code data errors are detected, the system repeats the sequence of steps starting from Step  340  described above with respect to  FIG. 7 , wherein the control system again monitors in Step  340  if Sensor B is blocked by the next sheet or document  16   c , and once Sensor B is blocked, as shown in  FIG. 25 , in Step  350  encoder  28  is reset and the length of the next sheet is measured. The system repeats Step  340  through Step  390 . In Step  380  the speed of Servo #1 is increased to Speed #2, and the speed of Servo #2 is decreased to Speed #2. Such transition is illustrated in  FIGS. 25 and 26 . Then, in Step  410  if the Sheet Set Count W is incomplete, Steps  420  through  450  are repeated. In addition, in Step  430  when Sensor A is unblocked by the next sheet or document, the speed of Servo #1 is decreased to Speed #1 and the speed Servo #2 is increased to Speed #1. If in Step  450  or Step  460  an error is detected, instead of returning to Step  340 , in Step  470  the system  10  initiates a system error routine and Servos #1 and #2 are both stopped. 
         [0049]    Referring now to  FIG. 9 , where in Step  410  ( FIG. 8 ) sheet Set Count “W” is complete, system  10  proceeds to Step  510  in which the speed of Servo #1 is decreased to Speed #1, and the speed of Servo #2 is reduced to Speed #3. This is illustrated in  FIGS. 27 through 29 , where the increase in the gap between sheet or document  16   c  being carried by transport wheels  24  and  32  and sheet or document  16   d  still in the feed wheel  18  with time is evident. Then, in Step  520 , the value of encoder  28  is monitored to determine whether or not such value is at or above a predetermined value, which value is referred to herein as “Stop Point ‘Z.’” When the value measured by encoder  28  reaches “Stop Point ‘Z’”, Servo #1 is stopped, which is illustrated diagrammatically in  FIG. 30  where only feed wheel  18  is rotating. Stop Point “Z” aligns sheet  16   b  in transport roller  32  for a programmable stopping point of the first page of the next set. Once Servo #1 is stopped, system  10  monitors in Step  540  whether Sensor A is unblocked; when unblocked, in Step  550  the completed Sheet Set should now be in Accumulator (see  FIG. 31 ). In Step  560  the system again monitors whether Sensor A is blocked by sheet or document  16   d , and when Sensor A is blocked, in Step  570  and as shown in  FIG. 32 , Servo #2 (feed roller servo  20 ) also stops, and sheet or document  16   d  is stopped at Alignment Point X (dictated by Sensor A). This again aligns the first sheet in the next set for feed sheet processing with a predictable starting point. The system  10  thus continues in such manner until all of the designated sets of sheets  16  have been successfully accumulated. 
         [0050]      FIG. 33  illustrates a typical prior art system whereby the feed wheel is controlled by an electromechanical clutch. In addition, there is a sensor positioned after the initial transport wheel, which is operated at a constant speed using a DC motor arrangement.  FIG. 33  illustrates the basic steps in such prior art accumulating arrangement system. Upon receiving a start signal, the system starts feeding the sheets using said electromechanical clutch to control the feed wheel. When the sheet reaches the transport wheel and is detected by sensor  1 , the feed wheel clutch is disengaged, is the sheet set count is complete, feeding of sheets is stopped as the complete sheet set should be in the accumulator. If the sheet set count is not complete, once sensor  1  is unblocked, the feed wheel clutch is engaged again to feed another sheet. Such process repeats until the sheet set count is complete. 
         [0051]    In contrast, at certain times during the feed process of the present invention, Servo #2 is directed by the system to operate at a speed considerably slower than the speed of Servo #1 during the such feed process. By Servo #1 driving the feed wheel  18  to turn at such considerably slower speed allows for precise control of the feed process, and is designed to create a larger gap between sets, and also correctly positions the next piece from the feeder. In addition, the system  10  also directs a change in speed of Servo #1 and Servo #2 from Speed #1 to Speed #2, where the speed of Servo #1 is increasing while Servo #2 is decreasing in speed. This also allows for even greater control of the spacing between sheets both in the same set and between the last sheet in the set being accumulated and the next sheet in the set to be accumulated. 
         [0052]    In U.S. Pat. No. 6,533,264 issued to M. N. Tranquilla on Mar. 18, 2003 entitled “Constant Space Document Feeder,” discloses an mechanism for generating a predetermined feed spacing between consecutive documents that is independent of the document length, wherein the feed wheel speed is reduced to an adjustment speed for an adjustment time period, and then is increased after the adjustment time period has expired. The adjustment speed and time period are determined by an adjustment module, wherein the trailing edge of a first document and leading edge of a second document are detected, which gives an initial feed spacing, and then the feed wheel speed is adjusted to give a predetermined or desired spacing. Tranquilla does not achieve the amount of control over the feed system that is achieved with the multiple speed system of the present invention. 
         [0053]    U.S. Pat. No. 7,635,127 issued to K. Kuse on Dec. 22, 2009, entitled “Sheet Feeding Apparatus,” discloses a sheet feeder including rotation speed controller for the adjusting the speed of a separation roller used to feed sheets from a stack between a first speed and a second speed. In particular, the first sheet is fed at a slower rotation speed than subsequent sheets. The primary purpose of the Kuse patent is to prevent leading edge folding of a document during feeding during copying or the like using an automatic document feeding apparatus. 
         [0054]    While the present invention has been described at some length and with some particularity with respect to the several described embodiments, it is not intended that it should be limited to any such particulars or embodiments or any particular embodiment, but it is to be construed with references to the appended claims so as to provide the broadest possible interpretation of such claims in view of the prior art and, therefore, to effectively encompass the intended scope of the invention. As used throughout, ranges are used as shorthand for describing each and every value that is within the range. Any value within the range can be selected as the terminus of the range. In addition, all references cited herein are hereby incorporated by referenced in their entireties. In the event of a conflict in a definition in the present disclosure and that of a cited reference, the present disclosure controls.