Abstract:
A stapler apparatus of the type using continuous belt-formed staples  200  includes a staple feed claw  25  for advancing the staples  200  sequentially to a stapling position  103,  and a drive means  50  for driving the staples  200  drawn to the stapling position  103.  A clincher means  40  bends the ends of the staples  200  driven into the sheets and pivots a staple feed pawl  25  interlocked to the staple bending operation of the clincher means  40  for sequentially feeding the staples  200  to the stapling position  103.  This construction lightens the load on the drive means to staple sheet stacks, facilitates smooth driving operation of the drive means, and reduces the occurrences of trouble.

Description:
BACKGROUND OF THE INVENTION  
         [0001]    The present invention relates to a stapler which binds a bundle of sheets such as a plurality of documents printed with a copying machine, a printer, or a composite of machines thereof, etc., with staples.  
           [0002]    Conventionally, this type of stapler has a staple feed pawl which successively advances and feeds staples composed of a belt roll of staples or stacked sheets of sheet-shaped staples loaded in a cartridge to a driving position, arranges a driver means for driving staples into the bundle of sheets on the side provided with the staple feed pawl, arranges a clincher means for appropriately bending the ends of the staple driven and pierced through the bundle of sheets with the driver means on the opposite side with the bundle of sheets as a boundary, and staples the bundle of sheets interposed between this driver means and the clincher means by swinging in the direction for being made adjacent to each other or separated from each other.  
         SUMMARY OF THE INVENTION  
         [0003]    However, the advance feeding of staples at this time is executed by interlocking the charging operation of the staple feed pawl with the operation of driving staples into the bundle of sheets with the driver means and the advance feeding operation of the staple feed pawl is executed according to the reciprocating movement of the driver means.  
           [0004]    However, in the method for charging the staple feed pawl by interlocking with the operation of driving staples into the bundle of sheets with the driver means, in addition to a great load being applied to the driver means just in the operation of driving staples into the bundle of sheets, additional load was added by charging the staple feed pawl, and depending on the condition such as the type of sheet, thickness of the bundle, etc., this was one reason for the occasional occurrence of so-called binding defect of not being able to execute driving of the staples completely due to the load thereof.  
           [0005]    The purpose of the present invention is to give consideration to the aforementioned problem in the conventional stapler and suppress the occurrence of trouble of binding defect by reducing the load when driving staples into a bundle of sheets as much as possible, executing a smooth staple driving process without executing the feeding of staples with the driving means, which has the greatest influence on the driving performance during the stapling operation, focusing on the clincher operation executed after driving the staples, and executing the staple feeding operation by linking to this clincher operation.  
           [0006]    The stapler apparatus of the present invention is comprised of continuous sheet shaped staples, a staple feeding means for feeding these staples to the driving position, a driving means for driving the staples at the driving position, and a clincher means for bending the staples driven with the driving means, and is equipped with an interlock operating means which operates said staple feeding means by being interlocked to the staple bending operation of the aforementioned clincher means. The aforementioned staple feeding means of the stapler apparatus in the present invention is composed from a friction roller, which contacts the continuous sheet shaped staples and rotates. The aforementioned staple feeding means of the stapler apparatus in the present invention is composed from a feed pawl, which contacts the continuous sheet shaped staples and reciprocates. The aforementioned clincher means of the stapler apparatus in the present invention includes a contact piece, which contacts the staples driven with the driving means and a clinch lever, which moves this contact piece and the aforementioned interlocked operating means is composed from this clinch lever and the staple feeding means. In the stapler apparatus of the present invention, the aforementioned driving means and clincher means are arranged at opposing positions by interposing the staples along with the aforementioned staple feeding means being positioned on the clincher means side.  
           [0007]    The stapler apparatus of the present invention is equipped with continuous sheet shaped staples, a staple feeding means which contacts these staples and reciprocates, an resilient means which urges this staple feeding means to the staple driving position side, a driver means which drives staples at the driving position, a clincher member which bends the staples driven with this driver means, and a clincher lever which moves this clincher member to the staple bending position and the retracted position retracted from the staple bending position, and the aforementioned clincher lever and staple feeding means are arranged to be able to make contact and to be separated. The aforementioned resilient means is charged with the movement of the aforementioned clincher lever in the stapler apparatus of the present invention to the staple bending position and the resilient force of the resilient means is bestowed to the staple feeding means with the movement to the retracted position.  
           [0008]    Below, an embodiment of a stapler according to the present invention will be described in accordance with the figures. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0009]    [0009]FIG. 1 is a plan view of a stapler according to the present invention.  
         [0010]    [0010]FIG. 2 is a partially exploded plan view of a staple replenishment mechanism of the stapler of FIG. 1.  
         [0011]    [0011]FIG. 3 is a plan view of a cartridge holder of the stapler of FIG. 1.  
         [0012]    [0012]FIG. 4 is a lateral view of the stapler of FIG. 1.  
         [0013]    [0013]FIG. 5 is a front view of the stapler of FIG. 1.  
         [0014]    [0014]FIG. 6 is a back view of the stapler of FIG. 1.  
         [0015]    [0015]FIG. 7 is a top view of the stapler of FIG. 1.  
         [0016]    [0016]FIG. 8 is a lateral view of the stapler of FIG. 1 in the clincher idle state.  
         [0017]    [0017]FIG. 9 is a lateral view of the stapler of FIG. 1 in the clincher sheet grasping state.  
         [0018]    [0018]FIG. 10 is a lateral view of the stapler of FIG. 1 in the clincher clinch completion state.  
         [0019]    [0019]FIG. 11 is a partial cross-sectional view of the required parts that describe the state in which the lock lever has locked the cartridge in the stapler of FIG. 1.  
         [0020]    [0020]FIG. 12 is a partial cross-sectional view of the required parts that describe the state in which the lock lever has released the cartridge lock in the stapler of FIG. 1.  
         [0021]    [0021]FIG. 13 is a schematic view that describes the driver drive system of the stapler of FIG. 1.  
         [0022]    [0022]FIG. 14 is a timing chart that describes the serial operation of the stapler of FIG. 1.  
     
    
     DESCRIPTION OF THE REFERENCE NUMERALS  
       [0023]    [0023] 10  Staple cartridge  
         [0024]    [0024] 20  Cartridge holder  
         [0025]    [0025] 30  Anvil unit  
         [0026]    [0026] 40  Clincher  
         [0027]    [0027] 50  Paper guide unit  
         [0028]    [0028] 60  Joint lever  
         [0029]    [0029] 70  Paper thickness absorption leaf spring  
         [0030]    [0030] 80  Main body frame  
         [0031]    [0031] 90  Lock lever  
         [0032]    MO Motor  
         [0033]    CO Connector base  
         [0034]    SE No staples/cartridge installation detection sensor  
         [0035]    HP Stapler home position sensor detector  
       DETAILED DESCRIPTION  
       [0036]    [0036]FIG. 1 shows a plan view of a stapler, in which  10  is a staple cartridge,  20  is a cartridge holder,  30  is an anvil unit,  40  is a clincher,  50  is a paper guide unit,  60  is a joint lever,  70  is a paper thickness absorbing leaf spring,  80  is a main body frame,  90  is a lock lever, MO is a motor, and CO is a connector base.  
         [0037]    [0037]FIG. 2 is a partially exploded plan view for describing a staple replenishing mechanism of the same stapler device, which comprises a stapler device main body  100 , a cartridge holder  20 , and a staple cartridge  10 . As the lock lever  90  is held down in an installation position, installation knobs  22  on the left and right sides of the cartridge holder  20  are first pinched together, and the cartridge holder  20  is guided by an installation guide  101  of the stapler main body  100  and installed therein. Detents  21  on the cartridge holder  20  are retained in catch holes  102  on the stapler main body  100 . By guiding guide protrusions  11  on the staple cartridge  10  along installation guides  23  in the cartridge holder  20  and inserting staple end  12  in this state, as will be described later in FIG. 11, the guide protrusions  11  on staple cartridge  10  engage with a lock lever release lever  96  that releases a set lever by pushing it in, and thus the lock lever  90  is released from its locked state. By engaging the lock lever  90  while pushing the guide protrusions  11  on the staple cartridge  10  toward a staple driver  103  from the rear, the cartridge holder  20  and the staple cartridge  10  are retained in a state in which they are constantly urged toward the staple driver  103  of the stapler main body  100 . Note that in the case of the staple replenishing mechanism, in order to try to make installation possible in the state in which the installation knobs  22  on the cartridge holder  20  are pinched inward, an installation procedure has been selected so that the cartridge holder  20  cannot be installed in the stapler device main body  100  when the staple cartridge  10  is inserted in the cartridge holder  20 , and the cartridge holder  20  has been designed so that it cannot be easily detached from the stapler main body  100 . Further, the method of urging the aforementioned cartridge holder  20  and the staple cartridge  10 , and the method of locking by means of the lock lever  90 , will be described in detail in the operational description of FIGS. 11 and 12 provided below. Note also the staple cartridge  10  stores staples  20  in a storage unit  13  therein, the staples  20  being straight, long and slender and grouped together side to side, linked together into a belt by means of an adhesive, and wound up into a roll. The staple end is prevented from returning back into the storage unit  13  by means of a staple non-return pawl not shown in the figures, and that end of the staples is stored in a state in which it abuts and is positioned on the tip portion  12  of the staple cartridge  10 . Note that in this case, to store the staples  200  using a snail-shaped staple cartridge  10 , the staples  200  are connected into a belt shape and wound into a roll, but depending on the structure of the staple cartridge  10 , it is acceptable to use staples  200  that are stacked as sheets of staples connected into a belt shape.  
         [0038]    [0038]FIG. 3 is a plan view of the cartridge holder of the same stapler device which, other than the detent  21 , the installation knobs  22 , and the installation guides  23 , comprises a magnet  24 A that is disposed such that it faces a position that a crank portion passes through which joins both ends of a staple that has been formed into a U-shape and driven into a stack of sheets, and that serves to eliminate unsatisfactorily bound staples from the device that are generated during the stapling process in the front of the stapler main body  100  (in the installation direction) by detaching the cartridge holder  20 . The cartridge holder  20  further comprises a non-magnetic magnet retaining member  24 B made of stainless steel and formed into a U-shape such that it holds a front portion of the magnet  24 A, the front portion thereof becoming a guide surface when a driver on the cartridge holder  20  slides, and a staple forwarding pawl means  25  that has a staple forwarding pawl  26  that steps the staples in the cartridge  10  to a stapling position  103  one by one and is pivotably supported on the lateral surfaces of the cartridge holder  20  at a forward pivot portion, and an engaging portion  27  that engages with protrusions on the clincher  40 . The cartridge holder  20  also comprises a step pressing spring  28  that urges the staple forwarding means  25  in a stepped manner, and a hole  29  from which the staple tip portion  12  of the cartridge  10  projects. The process by which an unsatisfactory staple is removed from the stapler device when it is stuck between the stapler device main body  100  and the cartridge holder  20  will now be described. First, in the state shown in FIG. 1, by using one hand to push the set lever  90  downward, as described in detail in FIGS. 11 and 12 below, the lock on the cartridge  10  is released, the cartridge  10  is pushed out of the device, and the cartridge is then pulled out.  
         [0039]    Next, as shown in FIG. 2, the installation knobs  22  on the cartridge holder  20  are pinched together, and by pulling out the cartridge holder  20  from the stapler device main body  100  in the state in which its engagement is released from the engagement holes  102  in the stapler device main body  100 , the space between the stapler device main body  100  and the cartridge holder  20  is open. Because the staples that are jammed in this space are generally made of steel wire about 0.5 mm in cross-section, are cut into 25 mm lengths, are grouped together side to side and linked together into a belt by means of a synthetic resin type of adhesive, they are easily attracted to the magnet  24 A. In this situation, because the staples have almost no weight and are easily attracted to the magnet  24 A provided on the front portion of the cartridge holder  20 , a flux density of 40 Gauss is sufficient. By pulling the cartridge holder  20  out of the stapler device main body  100 , one can widen the space between the stapler device main body  100  and the cartridge  20  in which the jammed staple is sandwiched, jammed staples can be attracted to the magnet  24 A, and can be taken out of the device while the cartridge holder  20  is pulled out of the stapler device main body  100 .  
         [0040]    Note that in this embodiment, the magnetic attraction force of the magnet  24 A is used. However, by pulling the cartridge holder  20  out of the stapler device main body  100 , jammed staples can be taken out therefrom, and instead of using the magnetic attraction force of the magnet  24 A, the same effect can be easily obtained by replacing the magnet  24 A or the staple facing portion of the magnet retaining member  24 B with an adhesive such as adhesive tape. In addition, the magnet  24 A or the staple attracting agent such as an adhesive or the like are attached to the cartridge holder  20  in this embodiment. However, even in a staple storage unit in which the cartridge  10  and the cartridge holder  20  are formed integral with each other, this can be attained by arranging it in a position that corresponds to the front portion of the cartridge holder  20  in which the magnet  24 A is attached. Furthermore, the aforementioned staple feeding means is not limited to the staple feed pawl means  25  composed of staple feed pawl  26 . It is acceptable if it possible to successively deliver staples to the staple driving position one by one by interlocking with the clincher so instead of the staple feed pawl means  25 , it is possible to use a friction roller that touches the continuous sheet-shaped staples and rotates and can idle when necessary. Furthermore, the aforementioned staple feeding means has a structure provided with forward pressure spring  28  to urge the staple feed pawl means  25  forward, but it can have a structure capable of advancing staples with the operation of the clincher by one end being supported directly by the clincher and providing a feed pawl to the other end which touches the staples.  
         [0041]    [0041]FIG. 4 is a lateral view of the same stapler, FIG. 5 is a front view of the same stapler, FIG. 6 is a rear view of the same stapler, and FIG. 7 is a view of the top of the same stapler. The configuration of the components will now be described in accordance with FIGS.  4  to  7 .  
         [0042]    As shown in FIG. 2, the staple cartridge  10  is a snail-shaped, and has the guide protrusions  11 , the storage section  13  that is a stapler case having a symmetrical shape from left to right and that can be split into two section from left to right, and stores the staples  200  that are staple sheets linked together into a belt and wound up into a roll, and a staple reverse prevention pawl  14  (shown in FIG. 9) that engages the front staple of the staples  200  such that it prevents it from returning back into the storage unit  13 .  
         [0043]    The cartridge holder  20  serves to hold the staple cartridge  10 . However, a description thereof will be omitted because it was described in detail earlier in FIG. 3.  
         [0044]    As shown in FIG. 5, the anvil unit  30  is an open U-shaped member in which the lower side thereof covers the top of the paper guide unit  50  disposed below it. The anvil unit  30  includes clincher arms  31  that pivot about a front pivot portion  32  overlooking the staple driver position  103  and which are respectively synchronous in the backward direction therewith, and engage with and fold a staple that has been sent out to the staple position, driven into a sheet bundle in a suitable position, and passed therethrough. The anvil unit  30  further comprises support arms  33  on which a fulcrum shaft  81  is pivotably supported. Plates on the left and right sides of the frame  80  are supported on and fixed to the fulcrum shaft  81 , and extend toward the direction in which the cartridge  10  is installed in the staple driver position  103 . The anvil unit  30  also comprises a bending protrusion  34  that is engaged with the frame  80  via a pulling spring  201  that is provided in a tensioned state therebetween, and a bending protrusion  35  that is engaged with one end of a pulling spring  202  that is engaged with the joint levers  60  via a pulling spring  201  provided in a tensioned state therebetween in order to constantly urge it in a direction away from the paper tray unit  50 . The anvil unit  30  also comprises a leaf spring attachment portion  36  that is attached to the paper thickness absorbing leaf spring  70 , which serves to release the drive interlock of the motor MO in response to the thickness of the paper bundle and prevent damage to the device, and a bending protrusion  37  that mates with a slit hole  63  in the joint levers  60 , and serves to restrict movement of the joint levers  60 .  
         [0045]    The clincher  40  is a U-shaped member that is open on the lower side thereof like the anvil unit  30 , and has a clinching unit  41  that pushes down on the anvil unit  30  and bends the staple, support arms  42  that are pivotably supported by the fulcrum shaft  81  that is the same fulcrum point for anvil unit  30 , and a connection shaft  43  that passes through the central portion of the anvil unit  30  and connects the joint levers  60  therewith. Furthermore, as shown in FIG. 10 described later, the interlock projection  44  which drives the staple feeding means forward by engaging the staple feeding means with the clincher operation is formed and an interlock means is configured with the interlock projection  44  and engaging portion  27  on the staple feeding means.  
         [0046]    The paper guide unit  50  is supported in its entirety by the device frame  80 , and has a configuration in the front of the staple driver position  103  that is generally well known. It includes a former means that first forms a straight staple into a U-shape, and a driver means that drives the staple formed into a U-shape by the former means into a sheet bundle at the driver position.  
         [0047]    Joint levers  60  connect the anvil unit  30  with the clincher  40  via the paper thickness absorbing leaf spring  70 . Because they receive the rotation force of the motor MO and pivot the anvil unit  30  and the clincher  40 , they have connection arms  61  that are rotatably supported on connection shaft  43  on the clincher  40  that extend upward, bending protrusions  62  that engage with the anvil unit  30  via pulling springs  202  provided therebetween in a tensioned state, slit holes  63  that mate with the bending protrusions  37  on the anvil unit  30  in order to restrict the position of the anvil unit  30 , and slit holes  64  that receive the rotational force of the motor MO, and mate with a pivot shaft  203  in order to pivot the anvil unit  30  and the clincher  40 .  
         [0048]    When the anvil unit  30  that is pivoted by the joint levers  60  pushes down on a sheet bundle and reaches the point where it cannot pivot any further, the paper thickness absorbing leaf spring  70  is a spring for so-called paper thickness absorption which serves to block any further pivot connection. It comprises a leaf spring having a plurality of leaves for suitably adjusting the spring pressure, is open on one end thereof, and is attached to a leaf spring attachment portion  36  on the anvil unit  30 .  
         [0049]    The main body frame  80  is U-shaped and open at the top such that it contains the staple cartridge  10 , the cartridge holder  20 , the anvil unit  30 , the clincher  40 , and the paper guide unit  50  on both sides thereof. It also supports the paper guide unit  50  on the staple driver position  103  side, and supports the stapler drive mechanism disposed in the rear thereof as shown in FIG. 12. In addition, it supports an auxiliary frame  85  attached thereto and formed from a die. The auxiliary frame  85  has a cam groove  86 , and shafts  87 ,  88 , and supports a cartridge lock mechanism, a detection sensor that is used both to detect cartridge installation and when the staples have been exhausted, and the like.  
         [0050]    As described explained above for FIG. 2, the lock lever  90  mountably supports the staple cartridge  10  and the cartridge holder  20  and constantly urges the staple cartridge  10  and cartridge holder  20  to the staple driver position  103 . As shown in FIG. 11, the cartridge lock mechanism that includes the lock lever  90  is supported by the auxiliary frame  85 . The lock lever  90  has a lock release knob  91  that is manually pushed downward when the staple cartridge  10  is removed, a slit hole  92  that is arranged so that the lock lever  90  can pivot forward and backward when the lock is released, a lock pin shaft  93  that moves in the cam groove  86  of the auxiliary frame  85  between a retain position that locks the staple cartridge  10  and a withdraw position that allows the staple cartridge  10  to be removed, a lock pawl  94  that engages the guide protrusions  11  on the staple cartridge  10 , and a protrusion  95  for detecting arm withdrawal that, in the release position, withdraws and retains a detection arm SE 2  on a no staples/cartridge installation detection sensor SE. In addition, the lock lever  90  has a lock release lever  96  that pivots in response to the lock lever  90  in the clockwise direction by moving the lock lever  90  that is in the locked, retain position to the withdraw position when the staple cartridge  10  is removed. Further, the lock pin shaft  93  is pivotably supported so that it constantly abuts the cam groove  86  in the auxiliary frame  85  by means of an urging spring  205 . Note that the lock release lever  96  is rotatably supported by the shaft  84  on the main body frame  80 , and has the contact arm  97  that abuts guide protrusions  11  on the staple cartridge  10  during cartridge installation on one end thereof, and the lock release arm  98  that moves the lock pin shaft  93  on the set lever  90  to the lock release position from the locked position on the other end thereof.  
         [0051]    Motor MO is a drive source that bends staples in a stapler into U-shapes in one continuous process, drives the staples into sheet bundles, and bends the staples driven therein. It decelerates the rotations of a standard DC motor, and drives each element by controlling the cam means with this rotation.  
         [0052]    The connector base CO connects an external control circuit with the motor MO, and a home position sensor (not shown in the figures).  
         [0053]    As shown in FIG. 11, the no staples/cartridge installation detection sensor SE is pivotably supported by the shaft  88  on the auxiliary frame  85 . The detection arm SE 2  that extends to one side due to urging spring SE 1  is urged to the position illustrated in the figure, in which it is able to detect whether or not the staples have been exhausted and whether or not a cartridge has been installed. A sensor detection protrusion SE 3  on the other side thereof works together with a detection sensor not shown in the figures, and is able to detect whether or not the staples have been exhausted and whether or not a cartridge has been installed by detecting an ON/OFF state. Further, a protrusion SE 4  in the area around the rotational shaft is pressed downward by means of the protrusion  95  on the lock lever  90  in order to retain the set lever  90  in the withdraw position during removal of the staple cartridge  10 . Note that the state in the figure shows the detection of staples replenished in the cartridge or a cartridge having staples when mounting a cartridge and the detection arm SE 2  in a state of touching a staple.  
         [0054]    As shown in FIG. 13, stapler home position detection sensor HP is comprised of a detection sensor protrusion CA 31  that is established in a suitable position overlooking an initial position on the circumferential surface of a driver cam rotor CA 30  that rotates by means of the motor MO, and an optical detection sensor that is disposed in a suitable position on the stapler device main body  100 .  
         [0055]    [0055]FIG. 8 is a lateral view of the clincher  30  of the same stapler in a clincher standby state. This position can always be detected by the home position sensor (not previously shown in the figures), and is a state in which stapling can occur after a stapling operation has been completed, after a jam has been cleared, or the like. A large opening is opened in staple driver position  103 , and is in a standby state such that a sheet bundle can be inserted therein.  
         [0056]    [0056]FIG. 9 is a lateral view of the clincher  30  of the same stapler in a sheet grasping state, and is shown in a state in which there are no sheets grasped therein in order to describe the maximum pivot limitation. In a real stapling operation, first the pivot of the anvil unit  30  is stopped within this pivot range due to the thickness of the sheet bundle, then clincher  40  pivots further and pivots the clincher arm  31 .  
         [0057]    [0057]FIG. 10 is a lateral view of the clincher  30  of the same stapler in a clinching completed state. In the state shown in FIG. 9, the interlock projection  44  formed by the clincher arm  31  pivots further, bends the tips of the staples, engages with the engaging portion  27  of the staple forwarding pawl  25  that is formed on the clincher arm  31 , and the staple forwarding pawl  25  resists and is charged by the urging force of the step pressing spring  28 . In this case, even if the staple reverse prevention pawl  14  does not engage with a staple and the staple connecting portion, and the staple returns half-way back, the staple has already been driven into the sheet bundle so jams do not occur when a staple returns half-way back or there is mis-positioning of the engaging position with the driver when driving a staple.  
         [0058]    [0058]FIG. 11 is a partial cross-sectional view of the necessary components that describe the state in which the lock lever  90  of the same stapler device locks the staple cartridge  10 , and shows a partial cross-sectional view of the necessary components of a lock mechanism for the staple cartridge  10  used when the staple cartridge  10  is installed in the stapler main body  100 . The figure shows the staple cartridge  10  in the installed state, and locked and retained in the stapler main body  100 , the lock lever  90  is urged in the direction of the staple driver position  103  by the urging spring  205  that comprises a tension spring that is stretched between the shaft  87  on the auxiliary frame  85  and the lock pin shaft  93  on the lock lever  90 . The lock pawl  94  on the lock lever  90  engages with the guide protrusions  11  on the staple cartridge  10 , and urge them toward the staple driver position  103 . In the figure, gaps are provided between the slit hole  92  on the lock lever  90  and the shaft  87  on the auxiliary frame  85 , and between the cam groove  86  in the auxiliary frame  85  and the lock pin shaft  93  on the lock lever  90 , so that the lock lever  90  can move further in the direction of the staple driver  103 . These gaps enable the set lever to retain and to lock the staple cartridge  10  in the retaining position without looseness at all times.  
         [0059]    [0059]FIG. 12 is a partial cross-sectional view of the necessary components that describe the state in which the lock lever  90  of the same stapler device releases the lock on the cartridge  10 . In the state shown in FIG. 11, when a staple is jammed between the staple main body  100  and the staple cartridge holder  20 , or due to a staple replenishment signal to the user by means of a signal from the no staples/cartridge installation detection sensor SE, first, while the lock release knob  91  on the lock lever  90  is pulled out to the nip side around the shaft  87  on the auxiliary frame  85  by the slit hole  92 , it resists the urging means  205  and the lock pin shaft  93  lowers along the cam groove  86  on the auxiliary frame  85  and to be retained in the state of the figure. In this state, the lock pin shaft  93  touches the engaging arm  98  on the interlock release lever  96  that releases the lock lever to pivot clockwise in resistance to the urging means, not shown in the drawing. The lock release arm  97  established on one end of the interlock release lever  96  to release the lock lever faces the position to engage the guide protrusions on the upper staple cartridge  10 , as can be seen in the figure, and the lock release arm  97  pushes the staple cartridge  10  to the outside of the device. The cartridge is then pulled further out to replenish staples. In this state, the staple cartridge  10  having been replenished with staples is inserted into the stapler main body  100  thereby the staple cartridge  10  guide protrusions  11  touch the lock release arm  97  to push the lock release arm  97  counter-clockwise thereby the engaging arm  98  on the lock release arm  97  pushes the lock pin shaft  93  on the set lever  90  upward. The lock pin shaft  93  faces the lock position to lock along the cam groove  86  on the auxiliary frame  85 , indicated in FIG. 11. At this time, the guide protrusion  11  on the staple cartridge  10  is at the position passing the engaging arm  98  and the guide protrusion  11  engages from behind by the engaging arm  98 . The urging spring  205  constantly urges toward the staple position  103  direction to make the locked state shown in FIG. 11. Note that in the locked state, the staple cartridge  10  is constantly urged to the staple driver position  103  that the end of the staple  200  is retained at the staple end  12  to always position the ends of the staples at the appropriate position at the staple driver position  103  so that it is impossible for staples to be unnecessarily taken out.  
         [0060]    [0060]FIG. 13 is a schematic view that describes the driver drive system of the same stapler device. It is composed of the drive motor MO that is comprised of a direct current motor, an output gear GA 10 , first and second reduction gears GA 20  and GA 30 , third and fourth reduction gears GA 40  and GA 50 , a fifth reduction gear GA 60 , a clincher drive eccentric cam CA 10 , an anvil drive eccentric cam CA 20 , a driver cam rotor CA 30  that forms an engagement pin CA 31 , and a driver drive eccentric cam CA 40  that forms the driver drive cam surface CA 42  and the indentation mated by the engaging pin CA 31 . The pivot shaft  203  that pivots the clincher  40  abuts the clincher drive eccentric cam CA 10 , and the pivot shaft  204  that pivots the anvil unit  30  abuts the anvil drive eccentric cam CA 20 . In addition, the detection protrusion CA 31  that detects the home position is configured to interrupt light at the home position to control the optical detection sensor HP established at the appropriate position on the stapler main unit  100  in one rotation.  
         [0061]    Description of Operation  
         [0062]    [0062]FIG. 14 is a timing chart that describes the serial operation of the same stapler. This serial operation will be described by using this FIG. 14, the drive system of FIG. 13, and FIGS.  8  to  10 . Drive motor MO receives a staple operation start signal from the device main body (not shown in the figures) and begins to rotate. As shown in FIG. 13, the output gear GA 10  receives the rotation of the drive motor MO, and the sixth reduction gear  60  starts to rotate via the first through fifth rotation gears  10 - 50 . The movement of this sixth reduction gear  60  corresponds to the movement of the drive motor MO of FIG. 14. First, the anvil pivot shaft  203  that abuts the anvil drive eccentric cam CA 20  starts the pivoting of anvil unit  30  to pivot within a range of a maximum of 2 sheets in a plurality sheets in a sheet bundle to be sandwiched (rotational angle 85° of the sixth reduction gear  60 ) and 50 sheets which is the tolerable number of sheets in a bundle, indicated by the dotted line in the figure. When doing so, the anvil unit  30  sandwiches the sheet bundle and cannot swing farther so the swinging of anvil pivot shaft  203  that abuts the anvil drive eccentric cam CA 20  is absorbed by the paper thickness absorbing leaf spring  70 . The former and driver, not shown in the figures and driven by the driver drive cam CA 40  shown in FIG. 1 is slidably supported in the vertical direction in the paper guide unit  50  moves slightly later than the pivoting of the anvil unit  30  and after the former has formed the straight staple ends into a U-shape, the driver continues to drive the staple ends formed into a U-shape into the sheet bundle an appropriate amount. Then, the pivot shaft  203  that abuts the clincher drive eccentric cam CA 10  starts the pivoting of the clincher  40  to bend the ends of the staples driven into and having pierced through the sheet bundle an appropriate amount. After bending, the clincher  40  returns and anvil unit  30  and the driver and former return to complete one series of the stapling operation. Note that after starting the rotation of the drive motor MO, the home position sensor HP slightly later because of the rotation of the driver cam rotating body CA 30  detects that the stapler device  100  is not in the home state or the prescribed initial state. By detecting whether or not it has returned to its initial state in the prescribed time, it checks to confirm the series of the stapler&#39;s operations and in the event that the home position sensor HP output after the prescribed operations is not recovered to its initial state, an error is determined for handling. Note, that although the starting of the operation is slightly delayed, in reference to the action of the drive motor MO, it is also possible to detect simultaneously.  
         [0063]    As is clear from the foregoing description, according to the present invention, after driving a staple, interlocking with the aforementioned bending operation of a clincher means the staple feeding means operates to move staples to a driving position so the load applied on driving means to drive staples in bundles of sheets is reduced, and the staple driving operation into the bundle of sheets is executed smoothly thereby checking the occurrences of trouble such as defective binding.