Abstract:
The present invention provides a device ( 1 ) for creasing, perforating and/or folding paper or other similar media to suit envelopes of various sizes. The device ( 1 ) includes a selectable creasing ( 15 ) or perforating head ( 20 ) which cooperates with an anvil ( 35 ), a Top Of Form sensor ( 46 ), a jam roller ( 59 ), associated pinch rollers ( 49, 63, 66 ) and a firmware for entering the paper size and type of paper for folding. After a predetermined paper length is fed into the paper path, the creasing ( 15 ) or perforating head ( 20 ) traverses a width of the paper to form a crease and after a predetermined length of paper passes the Top Of Form sensor ( 46 ), the jam/pinch rollers ( 59/49, 63, 66 ) are programmed to reverse in direction to cause the paper to buckle at the crease to form a fold. The types of folding operable by the device ( 1 ) are: letter, z, engineering, gate or half-fold.

Description:
FIELD OF THE INVENTION  
       [0001]    The present invention generally relates to a machine for creasing, perforating and folding paper or other similar media to suit envelopes of various sizes. 
       BACKGROUND OF THE INVENTION  
       [0002]    In a conventional creasing or perforating machine, a crease is obtained by compressing the entire length of a paper in between an anvil and a press plate or by compressing the paper in between two rotating rollers, with one roller having a groove and the other roller having a cooperating protrusion profile. On the other hand, perforation is obtained by passing the paper in between two rotating rollers, with one roller having a groove and the other roller having a cutting wheel or by rolling the perforating wheel or other mechanical cutter onto an anvil. Normally, the conventional creasing and perforating machines are not equipped with both features of creasing and perforating in a single machine, or if they are, interchanging of the creasing and perforating head unit will often involve manual work. 
         [0003]    Conventional folding machines that allow multiple types of folding, are complicated in design and they require large footprints. Most of the folding machines are limited to fold paper or the like in one specific paper size. Hard stops are commonly used for buckling the paper, which inevitably resulted in large footprints. When the folding machine is reduced to a portable size, typically it can only achieve one type of folding, mostly letter fold. 
         [0004]    U.S. Pat. No. 6,582,348 issued to Bacciottini, et al, discloses a machine for the creasing, perforating or circular cutting of sheets of paper. This machine shows improvement in terms of the system for feeding the starting sheets, the means for advancing each sheet and the creasing or perforating mechanism. The operations for perforating or cutting the sheets of paper are carried out with the same procedure for creasing, using suitable rotating tools mounted on the tool-handling shafts. 
         [0005]    U.S. Pat. No. 5,918,542, assigned to Hans E. Ruprecht Holding AG, discloses a device for perforating, die-cutting or creasing in printing machines. The device comprises a supporting foil which at two of its opposite sides is provided with strips for mounting onto a rubber blanket cylinder of a printing unit, whereby a component for perforating, die-cutting, cutting or creasing is affixed to the supporting foil. 
         [0006]    U.S. Pat. No. 5,147,275, assigned to Hunt Holdings, Inc., discloses an apparatus for automatically folding one or more sheets of paper into three substantially equal sections for later insertion into a mailing envelope. The design of the folding apparatus can only be used to achieve one type of folding, which is letter-fold in this case. 
         [0007]    U.S. Pat. No. 4,834,699 by Martin discloses an apparatus for sequentially folding paper, comprising three pair of rollers, an uncovered buckle chute and a paper stop mechanism. The paper stop mechanism makes use of a hard stop, such as an abutment or a flange, for stopping the forward movements of the paper. 
         [0008]    Despite the above development, there is still a need to provide a machine for creasing, perforating and folding paper and print media. 
       SUMMARY OF THE INVENTION  
       [0009]    The following presents a simplified summary to provide a basic understanding of the present invention. This summary is not an extensive overview of the invention and is not intended to identify key features of the invention. Rather, it is to present some of the inventive concepts of this invention in a generalized form as a prelude to the detailed description that is to follow. 
         [0010]    The present invention provides a device for creasing, perforating and folding paper or other similar media to suit envelopes of various sizes. According to one aspect of the invention, there is provided a paper folding and perforating device comprises a Top Of Form sensor, a selectable creasing or perforating head which cooperates with an anvil disposed in a paper path after the Top Of Form sensor, a jam roller and associated pinch roller disposed in the paper path after the anvil, and a firmware for entering the paper size and type of paper folding so that creasing and/or perforating positions are predetermined, wherein after a predetermined paper length is fed into the paper path, the creasing or perforating head traverses a width of the paper to form a crease and after the leading edge goes through the jam/pinch rollers, the jam/pinch rollers reverse in direction to cause the paper to buckle at the crease to form a fold. 
         [0011]    In one embodiment of the present invention, the creasing and perforating heads are separately mounted on opposite sections of a belt, which is strung on two pulleys. 
         [0012]    In another embodiment of the present invention, the creasing head comprises a ring whilst the perforating head comprises a perforating wheel, wherein the ring or perforating wheel is supported on a resilient means. 
         [0013]    In yet another embodiment of the present invention, each of the creasing and perforating heads comprise rollers at two sides for guiding traverse of the respective heads on two side plates. 
         [0014]    In another embodiment of the present invention, the creasing and perforating heads comprise rollers at two sides for guiding traverse of the respective heads on two side plates. 
         [0015]    According to another aspect of the present invention, the jam roller is coupled to a jam roller mechanism, wherein the jam roller mechanism comprises a unidirectional drive gear having a one-way clutch, a solenoid, a jam swing arm equipped with a drive train, said jam swing arm is pivotable about an end of the jam roller and operable by the solenoid from an initial or paper feed position to an activated or paper folding position, a transmission swing arm coupled to a feed roller disposed in the paper path before the jam/pinch rollers, said transmission arm is operable to pivot about said feed roller by swinging from a feed-through position to an activated position as a result of activation of the solenoid and jam swing arm, wherein the said jam and transmission swing arms are disposed on the same side of the device, such that after the predetermined leading edge of the paper goes through the jam/pinch rollers, activation of the solenoid engages the drive train on the jam swing arm to engage with said unidirectional drive gear, thereby reversing the direction of the jam/pinch rollers. 
         [0016]    In one embodiment of the present invention, when the solenoid is not activated, the paper continues to feed through the jam/pinch rollers. 
         [0017]    In another embodiment of the present invention, the jam roller mechanism can be used to form a z-fold or letter-fold, wherein in the formation of letter fold, the first fold is formed at about ⅓ of paper length measured from the paper&#39;s trailing edge by means of the jam roller mechanism, and wherein in the formation of z-fold, the first fold is formed at about ⅔ of paper length measured from the paper&#39;s trailing edge by means of the jam roller mechanism. 
         [0018]    In yet another embodiment of the present invention, the second fold is formed after the front portion of the paper hits the hard stop at its first folding edge, while the back portion of the paper continues to be fed upwards. 
         [0019]    The objectives and advantages of the present invention will become apparent from the following detailed description of embodiments thereof in connection with the accompanying drawings. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS  
         [0020]    Preferred embodiments according to the present invention will now be described with reference to the figures accompanied herein, in which like reference numerals denote like elements. 
           [0021]      FIG. 1  illustrates a perspective view of a creasing, perforating and folding device according to one embodiment of the present invention; 
           [0022]      FIG. 2  illustrates a perspective view of an input system of the device shown in  FIG. 1  in accordance with one embodiment of the present invention; 
           [0023]      FIG. 3  illustrates a perspective view of a creasing/perforating module of the device shown in  FIG. 1  according to another embodiment of the present invention; 
           [0024]    FIGS.  4 A 1  and  4 A 2  illustrate perspective views of creasing and perforating head units of the creasing/perforating module of the device shown in  FIG. 3  according to another embodiment of the present invention; 
           [0025]    FIGS.  4 B 1 ,  4 B 2 ,  4 B 3  and  4 B 4  illustrate side views of internal configuration of the creasing and perforating head units shown in FIGS.  4 A 1  and  4 A 2 ; 
           [0026]      FIG. 5  illustrates a perspective view of the creasing/perforating module of the device shown in  FIG. 3  having an additional side plate, in accordance with one embodiment of the present invention; 
           [0027]      FIG. 6  illustrates a perspective view of the creasing/perforating module of the device shown in  FIGS. 3 and 5  having a sensor at one of the side plates, in accordance with one embodiment of the present invention; 
           [0028]      FIG. 7  illustrates a side view of the creasing, perforating and folding device shown in  FIG. 1 ; 
           [0029]      FIG. 8  illustrates a perspective view of a folding module of the device shown in  FIG. 1  in accordance with one embodiment of the present invention; 
           [0030]      FIG. 9  illustrates a side view of the folding module of the device shown in  FIG. 1  in accordance with one embodiment of the present invention; 
           [0031]      FIG. 10  illustrates a side view of a Jam Roller mechanism of the device shown in  FIG. 1 , before the solenoid is activated, in accordance with one embodiment of the present invention; 
           [0032]      FIG. 11  illustrates a side view of the Jam Roller mechanism of the device shown in  FIG. 1 , after the solenoid is activated, in accordance with one embodiment of the present invention; 
           [0033]      FIGS. 12-16  illustrate side views of the letter-folding process using the folding module of the device, in chronological order; and 
           [0034]      FIGS. 17-21  illustrate side views of the Z-folding process using the folding module of the device, in chronological order. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0035]    Embodiments of the present invention shall now be described in detail, with reference to the attached drawings. It is to be understood that no limitation of the scope of the invention is thereby intended, such alterations and further modifications in the illustrated device, and such further applications of the principles of the invention as illustrated therein being contemplated as would normally occur to one skilled in the art to which the invention relates. 
         [0036]      FIG. 1  shows a perspective view of a paper handling device  1  according to one embodiment of the present invention. The paper handling device  1  is adapted for creasing, perforating or folding sheet materials, such as paper or similar print media. For simplicity, a paper is used in the following description but is not so limited. The handling device  1  comprises a folding module  5  (not shown in  FIG. 1 ), a creasing and perforating module  10 , a belt transmission system  2 , an input tray  41  and output P 1 , P 2 . The folding module  5  and the creasing and perforating module  10  are generally assembled between the input tray  41  and the output P 1 , P 2 . 
         [0037]    Operationally, the paper is fed into the handling device  1  through the input tray  41 , processed at creasing and perforating module  10  and/or folding module  5 , and finally outputted through output P 1 , P 2 , as a finished product. The operations are carried out through series of interconnected rollers and shafts mounted within the assemblies  41 ,  5 ,  10  that are driven by the belt transmission system  2 . The belt transmission system  2  comprises a motor (not shown), an upper belt transmission assembly  11  and a lower belt transmission assembly  12 . Having the belt transmission system  2  separated into the upper  11  and lower belt transmission assembly  12  allows a relatively small footprint and low height of the handling device  1 . 
         [0038]      FIG. 2  shows a configuration of the input system of the device  1 , in accordance with one embodiment of the present invention. The folding module  5  shares the same input system with the creasing and perforating module  10 , whereby multiple sheets of paper or other similar media are first placed on the input tray  41 . Each sheet of the paper will then be picked by a pick and separation module  42 , and passed to the input-feed roller  38 . In one embodiment of the present invention, the input tray  41  has a loading capacity of 30 sheets of paper. A width adjuster  43  is provided to align the stack of paper, as well as to prevent skewing of the paper during the pick and separation process. 
         [0039]      FIG. 3  shows the creasing and perforating module  10  of the handling device  1  in accordance with one embodiment of the present invention. The creasing and perforating module  10  comprises a creasing head  15 , a perforating head  20 , a belt and pulley system  25 , a speed reduction module  30  and an anvil  35 . 
         [0040]    The creasing head  15  and perforating head  20  are equipped with a creasing rubber ring  16  and a perforating knife  21 , respectively. The rubber ring or knife are removable from the respective head unit and can be replaced with other rubber rings or knives meant for other functions, as desired in another embodiment of the present invention. 
         [0041]    The belt and pulley system  25  is made up of a timing belt  26  that loops over two pulleys, a follower pulley  27  and a drive pulley  28 . The drive pulley  28  is connected to a motor  29  through a speed reduction module  30 . The speed reduction module  30  comprises a set of reduction gears  31  and a belt drive  32 . The reduction gears  31  work in conjunction with the belt drive  32  for stepping down the speed of the motor  29  in order to step up the torque on the drive pulley  28 . The combined use of reduction gears and belt drive is well known in the art, and hence, will not be described further herein. The anvil  35  is assembled in parallel to the belt and pulley system  25 . The anvil  35  has a similar length as the straight portion of the belt and pulley system  25  and supports the paper during the creasing or perforating process when a force from the creasing/perforating head exerts on the paper. 
         [0042]    The creasing head  15  and perforating head units  20  are mounted on the opposite sections of the timing belt  26 . Operationally, the two head units  15 ,  20  travel along the timing belt loop in a manner that when one of the head units is shifted over the anvil  35 , the other is disposed on the other side of the belt and pulley system  25 . When the head unit is over the anvil  35 , it will perform its respective function according to the rubber ring or knife mounted thereon. Such configuration allows the two head units  15 ,  20  to be used interchangeably by driving appropriately the belt and pulley system  25 . 
         [0043]    Toggling of the creasing and perforating functions in the present invention is automated and controlled by means of a firmware. The head unit recognition is also done by the firmware. The switching between creasing and perforating is done by conveying the appropriate head unit towards the anvil  35 . One end of the machine allows the flexibility for function toggling. The creasing and perforating head units  15 ,  20  are mounted to travel perpendicular to the paper feeding direction. Thus, the creasing and perforating processes are carried out across the width of the paper. The firmware is configurable to carry out multiple creases, perforations, or both on the same paper as required. The firmware operably controls the relevant rollers to carry out the necessary paper feeding towards the anvil  35 , and the belt and pulley system  25  conveys the appropriate head unit over the anvil  35  for creasing or perforating the paper thereon. 
         [0044]    FIGS.  4 A 1 - 4 A 2  and  4 B 1 - 4 B 4  show details of the head units shown in  FIG. 3 . Each head unit is equipped with two compression springs  36 , as can be seen in FIGS.  4 B 1 - 4 B 4  so that the creasing rubber ring  16  and perforating knife  21  are supported by the compression springs  36 . In this way, the contact force between the creasing rubber ring  16 /perforating knife  21  and the anvil  35  is controllable and optimized. In one embodiment of the present invention, 30 N of spring force, for example, is used to achieve an effective creasing and perforating process. In another embodiment of the present invention, the compression springs  36  is made up of a resilient piece of rubber. 
         [0045]    The head units  15 ,  20  are also equipped with tabs  17 ,  22  and metal rollers  37 , as shown in FIGS.  4 A 1 - 4 A 2 . The creasing  17  and perforating tabs  22  are parts of the device&#39;s sensing system, which will be described further hereinafter. The metal rollers  37  serve the purpose of reducing frictional forces as the two head units  15 ,  20  travel back and forth along guiding grooves  33  on side plates  34  located on both sides of the belt and pulley system  25 , as can be seen in  FIG. 5 . 
         [0046]      FIG. 6  shows a head unit recognition system  40  of the creasing and perforating module  10  in accordance with one embodiment of the present invention. The head unit recognition system  40  comprises a sensor  39  located on the side plate  34  opposite that of the motor  29 . The creasing  17  and perforating tabs  22  on the head units  15 ,  20  are used by the sensor  39  to differentiate the creasing head  15  from the perforating head  20 . In one embodiment, the perforating tab  22  is shorter in length than the creasing tab  17 . By monitoring the length difference of the tabs, the sensors  39  is able to identify which head unit is currently facing downwards towards the anvil  35 . Based on the determination, a respective head unit is then shifted over the anvil  35  for the process to be carried out, according to the selection previously set within the firmware. 
         [0047]      FIG. 7  shows a side view of the creasing/perforating module, together with its input and output system. A Top Of Form (TOF) sensor  46  located near the middle of a base support  47  is used to detect the leading and trailing edges of the paper to be creased or perforated. The Top Of Form (TOF) sensor  46  is used together with the firmware for accurate distance calculation, thus allowing precise creasing and perforating at the desired predetermined locations on the paper. 
         [0048]    The use of the Top Of Form (TOF) sensor  46  combined with the firmware in the present invention allows the user to have multiple crease and perforation lines on the paper or other similar media in a single pass. There is also no distance limitation between lines in a single pass. Hence, the paper or similar media to be processed on, only have to go through the device  1  once. This eliminates the need for the paper to be restacked on the input tray  41  every time another crease/perforation process need to be done on it, as required in the conventional creasing or perforating device. An output system comprised of rollers  48  is utilized for ejecting the paper from the lower exit path P 1  of the device  1 , once the creasing and perforating processes are completed. 
         [0049]    The creasing and perforating module  10  of the present invention offers advantages of a simple design with an automated toggling between the creasing and perforating functions and smaller footprint, as compared with the conventional creasing or perforating device. 
         [0050]      FIG. 8  and  FIG. 9  show perspective view and side view respectively of the folding module  5 , according to one embodiment of the present invention. The folding module  5  is provided to handle different types of folding and different paper sizes, for example, ranging from A4 to B sizes. Conventional folding device normally relies on hard stops as means for folding or buckling. This folding module  5  utilizes a “Jam-Roller” mechanism  50  to form the first fold and hard stop for any subsequent folding. 
         [0051]    The Jam-Roller mechanism  50  comprises a solenoid  52 , a drive train  61  coupled to a jam swing arm  53 , a transmission gear train  62  coupled to a transmission swing arm  54 , a unidirectional drive gear  57  built in with a one-way clutch  58 , a jam roller  59  and a compression roller  63 . A set of four feed rollers  38 ,  44 ,  59 ,  64  is used to transport the paper from one point to another along the paper-folding path, as will be better explained later. The feed rollers  38 ,  44 ,  59 ,  64  will be further described in details hereinafter. 
         [0052]    The jam swing arm  53  and the drive train  61  are coupled to the jam roller  59 , whereas the transmission swing arm  54  and the transmission gear train  62  are coupled to the second feed roller  44 . There is an additional gear  56  used to connect the transmission gear train  62  to the drive train  61 . This additional connecting gear  56  is always in contact with the drive train  61 . The swinging up or down motion of the transmission swing arm  54  results in the transmission gear train  62  engaging or disengaging with the drive train  61 , through the additional connecting gear  56 . The solenoid  52  is linked to the jam swing arm  53 , such that upon its activation by the firmware, the jam  59  and compression roller  63  change in reverse direction for forming the first fold on the paper. The details of how the Jam Roller mechanism  50  works will be described further hereinafter. 
         [0053]    The same Top Of Form sensor  46  is also used in the folding module  5  for the same purpose of detecting the leading and trailing edge of the paper to be folded. The use of Top Of Form sensor  46  together with the firmware facilitates accurate distance measurement, such that precise folding on the desired predetermined locations of the paper can be achieved. 
         [0054]    With the Top Of Form sensor  46 , the firmware is then able to control the time of activation of the solenoid  52 . Activating the solenoid is the first step of starting the folding process by the Jam Roller mechanism  50 .  FIG. 10  and  FIG. 11  show the configuration of the Jam Roller mechanism  50 , before and after the solenoid is activated, respectively. 
         [0055]    Before the solenoid  52  is activated, the plunger of the solenoid  52  is extended and the transmission swing arm  54  is in the swung up position, such that the transmission gear train  62  is engaged directly with the connecting gear  56  and indirectly with the drive train  61 . As a result, the second roller  44  and jam roller  59  rotate in the same direction i.e. anticlockwise as seen in  FIG. 10 , thus feeding the paper outward from the lower exit path, as indicated by the arrow P 1  in  FIG. 9 . 
         [0056]    When the solenoid  52  is activated and the plunger of the solenoid  52  is retracted, the jam swing arm  53  together with the drive train  61 , are being pulled towards the gear  57 . At the same time, the transmission gear train  62  is disengaged from both the connecting gear  56  and the drive train  61 . A bottom part of the jam swing arm  53  is designed in such a way that once the jam swing arm  53  is swung up, it causes the transmission swing arm  54  to swing down thereby disengaging the transmission gear train  62  from the connecting gear  56  and the drive train  61 . 
         [0057]    The gear  57  with one-way clutch  58  is only allowed to rotate in one direction, as indicated by the arrow R 1  in  FIG. 1 . Once the drive train  61  is engaged with the gear  57 , its rotating direction will be reversed. Since, the jam roller  59  is connected to the drive train  61 , its rotating direction is reversed as well, thus stopping the paper from being fed outward from the lower exit path P 1 . The rotating direction reversal of the jam roller  59  is followed by two actions: engagement of drive train  61  to the gear  57  with one way clutch  58  and disengagement of transmission gear train  62  from the connecting gear  56  and the drive train  61 . This is done after a predetermined paper length has been fed outward from the lower exit path P 1 , while the paper itself is still being fed forward by the second feed roller  44 . As a result, the paper buckle at the desired predetermined location and the first fold is formed. The designated point of buckling is pulled in between the second feed roller  44  and a buckling roller  49  to achieve the fold edge. The use of one-way clutch  58  ensures immediate release of hold, such that once the rotating direction of the jam roller  59  is reversed, the portion of the paper which has been fed outward from the lower exit path is fed smoothly backwards. This is done with help from the compression roller  63 , located right below the jam roller  59 , by reversing its direction at substantially the same time as the jam roller  59 . This configuration is able to minimize risk of the paper being halted or any other possible error at the point of the rollers&#39; direction reversal. 
         [0058]    The types of folding, be it letter-fold or Z-fold, is determined by the amount of paper length that has been fed outward from the lower exit path P 1 . As mentioned previously, the firmware uses the information obtained from the Top Of Form sensor  46  to control the length of the paper to be fed outward from the lower exit path P 1 , based on the type of folding chosen by the user. 
         [0059]    When the device  1  is in use, the user selects one or more desired functions; creasing, perforating and/or folding function. Regardless of the function(s) selected by the user, firstly the paper from the input tray  41  will be passed to the input-feed roller  38  and the Top Of Form sensor  46  will subsequently detect its leading edge. 
         [0060]    In one embodiment of the present invention, the user selects creasing and/or perforating function, without any folding. First, the user determines the setting of the crease and perforation in terms of the sequence and locations. The firmware then controls the relevant rollers to perform necessary paper feeding towards the anvil  35 . The appropriate head unit is then conveyed over the anvil  35  for creasing or perforating the paper thereon, according to the user settings. When the necessary creasing and perforating processes are completed, the paper is ejected from the lower exit path P 1  of the device  1 , by a set of output rollers  48 . 
         [0061]    In another embodiment of the present invention, the user selects folding function, without any creasing or perforating. The user then first enters the desired type of folding and paper size as variables in the firmware. Once the Top Of Form sensor  46  detects the leading edge of the incoming paper, the firmware uses the user settings to control the time of activation of the solenoid  52 . 
         [0062]      FIGS. 12-16  show how a letter fold is formed chronologically using this folding module  5 . The solenoid  52  is activated when the portion of the paper fed outward from the lower exit path P 1  reaches a predetermined length, such that the first buckle or fold is then formed at about ⅓ of paper length measured from the paper&#39;s trailing edge, by means of the previously explained Jam Roller mechanism  50 . The paper, now having its first fold, continues to be fed upwards until it hits a hard stop  51 . The second fold is then formed after the front portion of the paper hits the hard stop  51  at its first folding edge, while the back portion of the paper continues to be fed upwards. The designated point of buckling is pulled in between the second buckling roller  66  and the discharge roller  64 , which is also the last out of four feed rollers used in this folding module  5 . The second folding edge is then created at about ⅓ of paper length measured from the paper&#39;s initial leading edge. Finally, the letter-folded paper is discharged from the device&#39;s upper exit path, as indicated by the arrow direction P 2 . 
         [0063]    As can be seen from  FIGS. 17-21 , the process of forming a Z-fold is very similar to the letter-folding process as explained above. The only difference is the solenoid activation timing, which is set in such a way that the first buckle or fold is formed at about ⅔ of the paper length, measured from the paper&#39;s trailing edge, instead of ⅓ of the paper length as for the case of letter-fold. The second folding edge is then formed at about ⅔ of paper length, measured from the paper&#39;s initial leading edge, instead of ⅓ as for the case of letter-fold. 
         [0064]    Other types of folding such as engineering-fold, gate-fold or half-fold can also be made by utilizing the same Jam-Roller mechanism  50 . 
         [0065]    With present invention, the user may even select the combination of all the creasing, perforating and folding functions. In this case, all the necessary creasing and perforating processes are first carried out on the paper in the creasing and perforating module  10 . The paper is then fed to the folding module  5 , to be folded according to the user selection, instead of relying on buckling of the paper between relevant feed rollers. The paper is then ejected from the device  1  from the upper exit path P 2 , as a finished product. 
         [0066]    The folding module  5  of the present invention improves on the method used by conventional folders, which rely solely on hard stops for folding. The present invention is able to achieve multiple folds without the need of multiple hard stops, hence increasing flexibility in folding and reducing the required footprints at the same time. In addition to that, the device  1  of the present invention allows different types of folds for different paper sizes. 
         [0067]    While specific embodiments have been described and illustrated, it is understood that many changes, modifications, variations and combinations thereof could be made to the present invention without departing from the scope of invention. For example, instead of setting the folding positions from the trailing edge of a paper, the leading edge can be used.