JP2010194640A - Post-processing device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent a disturbance of a cut part due to the shift of a sheet during a cutting operation and reduce a supply energy for pressing the sheet by a sheet pressing part during the cutting operation in a post-processing device for pressing the sheet by the sheet pressing part and cutting the butt end of the end part of the sheet. <P>SOLUTION: A reverse action preventing part is provided for preventing the pressing part from moving in a direction separating from the sheet when the sheet pressing part is located at a position for pressing the sheet. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a post-processing apparatus having a cutting unit that cuts an edge portion of a sheet, and an image forming system in which the post-processing apparatus is connected to an image forming apparatus.

  Some post-processing apparatuses include a cutting unit for trimming a sheet that has undergone a predetermined post-processing to a predetermined size, or for trimming the end of a bound sheet bundle.

  For example, when performing saddle stitching on a post-processing device and folding it along a saddle stitch to make a booklet, the edge of the paper folded along the saddle stitching portion may become uneven, It is possible to improve the appearance quality of a booklet by cutting the edge of the folded paper and aligning the edges of the paper.

  Usually, the cutting is performed by cutting a predetermined position of the paper placed on the mounting table with a cutting blade. When the cutting is performed, a cutting force is applied to the paper from the cutting blade, but the paper may be displaced from the loading position by the cutting force. The misalignment of the paper that is being trimmed will disturb the cut edge that has been trimmed, affecting the appearance quality.Therefore, it is necessary to press the paper with a large pressing force so that the paper does not slip until the trimming is completed. Is called.

  Therefore, a technique has been proposed in which hydraulic pressure is used as a power source for generating a pressing force, a pressing plate is connected to the hydraulic cylinder, and the pressing plate is operated by the hydraulic pressure generated by the hydraulic cylinder to press the paper ( For example, see Patent Document 1).

  However, if the pressing force is generated by a hydraulic system, a hydraulic pump, a hydraulic cylinder, hydraulic piping, and the like are required, and the apparatus itself may be complicated and large.

  For this reason, a technique has been proposed in which a motor is used as a power source, and the rotational movement of the motor is converted into a linear motion to operate the pressing plate to press the paper.

  For example, in Patent Document 2, a male screw member provided with a male screw is rotated by a motor, and the rotation of the motor is converted into a linear motion of a female screw member that is screwed to the male screw member to operate a pressing plate connected to the female screw member. Techniques to make it have been proposed.

  Patent Document 3 discloses a technique for increasing the amount of force to operate the pressing plate by transmitting the linear motion of the female screw member to the pressing plate via a link mechanism. Patent Document 4 discloses a straight line of the female screw member. There has been proposed a technique for increasing the amount of force for operating the pressing plate by transmitting the motion to the pressing plate via a moving pulley.

JP 2000-254892 A JP 2005-88131 A JP 2003-136471 A JP 2006-26756 A

  As described above, if the paper is shifted during the cutting, the cut edge is disturbed, so the paper is pressed with a predetermined pressing force from the start of the cutting until the cutting is finished. Is needed.

  In Patent Document 1, the pressing plate is pressed by the hydraulic pressure until cutting is completed, and the paper is pressed while being held at the pressing position. However, since the oil pressure is maintained from the start of cutting until the end of cutting, a large amount of energy is required.

  In Patent Documents 2 and 3, the motor is energized when the pressing plate is in the pressing position. Although the pressing plate stays in the pressing position while being pressed by the energization of the motor, a large amount of electric power is consumed because the energization of the stopped motor is performed until the cutting is completed.

  On the other hand, in Patent Document 4, when pressing is performed, the driving of the motor is stopped and cutting is performed. During this time, the pressing plate is biased in the direction of the pressing position by the spring and presses the paper. However, the phenomenon that the pressing plate is pushed back from the position where the sheet is pressed by the cutting force applied from the cutting blade during the cutting is not solved.

  SUMMARY OF THE INVENTION An object of the present invention is to provide a post-processing apparatus that does not cause a disorder of the cut end due to a sheet slippage during cutting and that has a small supply energy for pressing the sheet during cutting.

  The above problem is solved by the following means.

1. A paper placement section for placing paper;
A paper pressing portion disposed so as to be close to and away from the paper placement portion;
A pressing movement unit for moving the paper pressing unit;
A cutting unit for cutting the paper placed on the paper placement unit;
Have
The paper pressing unit is moved by the pressing movement unit, and after the paper is placed on the paper placement unit, the paper pressing unit approaches the paper placement unit to press the paper, and the cutting of the paper by the cutting unit is completed. In the post-processing device that is separated from the paper stacking unit,
A post-processing device having a back-motion preventing unit that prevents the sheet pressing unit from moving in a direction away from the sheet placing unit when the sheet pressing unit is in a position for pressing the sheet. .

2. The back motion prevention unit is
A first position that constitutes the pressing movement unit and abuts on any component driven by the movement of the paper pressing unit to stop the movement of the component, and is driven away from the first position. A second braking position that does not interfere with the
The braking unit is moved to the first position from the time when the sheet pressing unit reaches at least a position where the sheet is pressed until the cutting is completed, and the sheet pressing unit is moved to the sheet placing unit. 2. The post-processing apparatus according to claim 1, wherein the post-processing apparatus is moved to the second position when approaching or separating from the sheet placing portion.

3. The pressing and moving part is
A pressing driving force generating section for generating a rotational driving force;
A driving pulley that is rotated by the pressing driving force generation unit; a driven pulley; and a driving belt that is stretched between the driving pulley and the driven pulley, and reduces the rotation of the pressing driving force generation unit. A belt reduction mechanism that transmits the rotational driving force to the driven pulley;
A screw pressing portion comprising: a female screw portion arranged in the paper pressing portion; and a male screw portion provided with a male screw screwed into the female screw portion;
Have
The male screw part is rotated by the driving force of the pressing driving force generating part transmitted through the belt reduction mechanism part, the female screw part is moved in the axial direction of the male screw part, and the paper pressing part is Move in a direction approaching or separating from the paper placement unit,
3. The post-processing apparatus according to 2, wherein the component that contacts when the braking portion is in the first position is the drive belt.

4). The back motion prevention unit is
Constituting the pressing movement part, and a locked part arranged on any part driven by the movement of the paper pressing part;
Engaging with the locked portion, the component is allowed to be driven in a direction in which the paper pressing portion is moved in a direction approaching the paper placement portion, and the component is A first mode that prevents the component from being driven in a direction away from the placement unit; and the component is separated from the locked portion, and the component is separated from the paper placement unit. A second mode that allows it to be driven in a direction to be moved, and a locking portion operable in two modes;
Have
The reverse motion prevention unit operates in the first mode when the paper pressing unit is at least in a position to press the paper placed on the paper placing unit, and the cutting of the paper by the cutting unit is completed. 2. The post-processing apparatus according to claim 1, wherein the post-processing device operates in the second mode when the paper pressing portion is separated from the paper placement portion.

5). The pressing and moving part is
A pressing driving force generating section for generating a rotational driving force;
A driving pulley that is rotated by the pressing driving force generation unit; a driven pulley; and a driving belt that is stretched between the driving pulley and the driven pulley, and reduces the rotation of the pressing driving force generation unit. A belt reduction mechanism that transmits the rotational driving force to the driven pulley;
A screw pressing portion comprising: a female screw portion arranged in the paper pressing portion; and a male screw portion provided with a male screw screwed into the female screw portion;
Have
The male screw part is rotated by the driving force of the pressing driving force generating part transmitted through the belt reduction mechanism part, the female screw part is moved in the axial direction of the male screw part, and the paper pressing part is Move in a direction approaching or separating from the paper placement unit,
The locked portion is a ratchet wheel disposed on the driven pulley,
When the reverse movement preventing portion operates in the first mode, the locking portion engages with the ratchet wheel while the driven pulley moves the paper pressing portion closer to the paper placement portion. And the driven pulley is prevented from being driven in a direction away from the sheet placing portion, and when operating in the second mode, separated from the ratchet wheel, 5. The post-processing apparatus according to 4 above, wherein the driven pulley is a ratchet pawl that allows the paper pressing portion to be driven in a direction approaching the paper placement portion.

  6). 6. The post-processing apparatus according to 3 or 5, wherein the screws arranged in the male screw portion and the female screw portion are trapezoidal screws.

  7). The post-processing apparatus according to any one of 1 to 6 is connected to an image forming apparatus that forms an image on a sheet, and the post-processing apparatus is linked to the operation of the image forming apparatus. An image forming system that performs post-processing on a sheet on which an image is formed by the image forming apparatus.

  According to the present invention, it is possible to provide a post-processing device that does not cause a disorder of the cut edge due to the paper being shifted during cutting and that has low supply energy for pressing the paper during cutting.

1 is a cross-sectional view of an image forming system in which an image forming apparatus A is connected to a post-processing apparatus B that is an embodiment of the present invention. FIG. 6 is a schematic diagram illustrating sheet conveyance in a half-folding and saddle stitching process of post-processing apparatus B. 4 is a left side view of the post-processing apparatus B. FIG. 2 is a diagram illustrating a sheet cutting apparatus 100 in a post-processing apparatus B. FIG. It is a figure explaining the back motion prevention part. During the cutting operation, the paper pressing member is prevented from being reversely moved by engaging with the locked portion disposed on the second pulley, which is one of the parts driven by the reverse movement of the paper pressing member. It is a figure explaining the paper cutting apparatus which has a back movement prevention part which performs. It is a figure explaining the back motion prevention part.

  The present invention will be described based on the embodiments, but the present invention is not limited to the following embodiments.

  FIG. 1 is a cross-sectional view of an image forming system in which an image forming apparatus A is connected to a post-processing apparatus B that is an embodiment of the present invention. The post-processing apparatus B can perform the saddle stitching process and the cutting process, and the cutting process is performed in the paper cutting apparatus 100 of the post-processing apparatus B. It should be noted that the post-processing apparatus incorporating the cutting apparatus according to the present invention can be configured to be used alone. The post-processing apparatus of the present invention and the image forming system including the post-processing apparatus of the present invention are not limited to the following embodiments.

<Image forming apparatus A>
An image forming apparatus A shown in FIG. 1 includes an image reading unit 1, an image processing unit 2, an image writing unit 3, an image forming unit 4, a paper feeding cassette 5, a first paper feeding unit 6A, a second paper feeding unit 6B, The image forming apparatus includes a fixing device 7, a paper discharge unit 8, an automatic double-sided copy paper supply unit (ADU) 8 </ b> A, and an operation unit 9.

  A post-processing apparatus B having a sheet cutting apparatus 100 is connected to the paper discharge unit 8 side on the left side of the image forming apparatus A shown in the figure.

  From the operation unit 9, it is possible to select and input processing functions of the image forming system including the image forming apparatus A, the post-processing apparatus B, and the like.

  Based on the information input from the operation unit 9, the image forming apparatus A transports paper stored in the paper feed cassette 5 or the large-scale paper feed device LT connected to the right side of the image forming apparatus A in the figure. Then, the image is formed and sent from the paper discharge unit 8 to the post-processing apparatus B.

  The main control unit 10A of the image forming apparatus A has a communication unit 10C, and is connected to the post-processing control unit 10B through the communication unit 10D of the post-processing apparatus B via the communication line 10E.

<Post-processing device B>
FIG. 2 is a schematic diagram illustrating sheet conveyance in the half-folding and saddle stitching process of the post-processing apparatus B. FIG. 3 is a left side view of the post-processing apparatus B.

  When the bookbinding process for half-folding and saddle stitching is set and input in the operation unit 9 of the image forming apparatus A, the sheet S discharged from the image forming apparatus A is introduced into the inlet 11 of the post-processing apparatus B, and It is nipped by the entrance roller 12 and is conveyed to the paper conveyance path r1 below the conveyance path switching means Z.

  The sheet S conveyed to the sheet conveyance path r1 descends substantially vertically and is temporarily stopped and stored at a predetermined position. At the first stop position Q1, a plurality of subsequent sheets S are stacked and stored.

  The accommodated sheet S is moved in a right angle direction by the conveying roller pair 18A, 18B, the first conveying roller pair 18C, 18D, and a guide plate (not shown), and the sheet conveying path wraps around the front side Bf inside the post-processing apparatus B. At r2, the paper surface passes in an upright state, and temporarily stops at the second stop position Q2.

  Next, the sheet S is conveyed vertically upward by the second conveying roller pair 18E, then deflected in the horizontal direction, and then moved along the sheet conveying path r3.

  The aligning means (not shown) is disposed on the downstream side of the sheet conveyance path r3 in the sheet conveyance direction, and is positioned by bringing the leading end of the sheet into contact with the sheet conveyance path r3, and temporarily stops at the third stop position Q3.

  On the downstream side of the aligning unit in the sheet conveyance direction, the center folding unit 30 is arranged. The middle folding means 30 is composed of a folding roller, a folding plate, and the like. The center of the sheet S is pressed by the folding plate, the center of the sheet is passed through the folding roller, and then the folding roller is reversed, The middle folding process is performed at the center.

  A sheet (hereinafter referred to as a signature SA) on which the folding process is performed by the folding unit 30 to form the fold portion b is returned to the original horizontal conveyance path. The signature SA is continuously conveyed by the conveying belt 41 of the conveying means 40, the conveying claw 42, and the introduction guide member 51 of the signature guide means 50 to the sheet conveying path r4 in the extension line direction of the fold portion b, and the saddle stitching means 60. Is sent to.

  As described above, the saddle folding means 30 performs the folding process on the sheet S before the saddle stitching process, firmly attaches the fold part b, and sequentially feeds the sheet S to the saddle stitching means 60, so that the sheet is fed after the saddle stitching is performed. Compared with the method of bending the sheet bundle SS, it is possible to produce a sheet bundle SS in which the folds b are less swollen.

  The signature SA that has been subjected to the middle folding process in the middle folding means 30 is advanced by the conveyance means 40 in the direction of the paper conveyance path r4 and placed on the hook stacking means 61 of the saddle stitching means 60 (see FIG. 3). The subsequent signature SA that has undergone the middle folding process continues to be sequentially stacked on the hook stacking means 61 through the sheet conveying path r4.

  The hook stacking means 61 is composed of two guide plates substantially orthogonal to each other, and is fixed to the main body of the post-processing apparatus B. In the vicinity of the top of the hook stacking means 61, a paper receiving member 61 </ b> A that can be lifted and lowered by a spring is supported by the needle receiving mechanism 64.

  The top portion of the sheet receiving member 61A has a convex shape that is substantially perpendicular to the upper side, and the fold portion b of the signature SA that has been subjected to the middle folding process is sequentially placed on the top ridge line.

  A plurality of signatures SA placed on the hook stacking means 61 and the sheet receiving member 61A are aligned by the width aligning means 62.

  A needle striking mechanism 63 is fixedly disposed above the sheet receiving member 61A. Inside the hook stacking means 61, a needle receiving mechanism 64 is supported so as to be movable in the vertical direction together with the sheet receiving member 61A. Two sets of binding means having a two-part structure composed of the needle-striking mechanism 63 and the needle-receiving mechanism 64 are arranged in the direction of the fold portion b of the paper S. When the saddle stitching process is set in the operation unit 9, the needle receiving mechanism 64 moves up and the needle driving mechanism 63 operates to perform the saddle stitching process. That is, the two sets of binding means strike the binding needles SP at two centrally distributed locations along the fold portion b of the signature SA on the paper receiving member 61A.

  The sheet bundle SS that has been subjected to the saddle stitching process in the saddle stitching means 60 is held by a support member 72 fixed to the distal end portion of the arm member 71 of the booklet taking-out means 70 and is swung in the direction of the one-dot chain line by the arm member 71. It is conveyed to the booklet conveying means 80.

  The sheet bundle SS transported to the booklet transport unit 80 is placed on the transport belt 82 in a state where the free ends are closed with the fold portion b interposed therebetween. The sheet bundle SS is conveyed obliquely downward by the rotation of the conveyance belt 82, is held in an inclined state, is transferred by the rotating conveyance belt 83, and stops at a predetermined position. Thereafter, the conveyor belt 83 swings and is supported in a horizontal state.

  The fore edges SSa, which are the free ends of the sheet bundle SS opposite to the crease part b, are uneven. The sheet cutting apparatus 100 cuts and aligns the fore edges SSa of the sheet bundle SS placed on the transport belt 83 in a horizontal state. Reference numeral 131 denotes a cutting blade 131 in the paper cutting apparatus 100, and 111 denotes a paper pressing member 111 that presses the paper. Details of the sheet cutting apparatus 100 including the cutting blade 131 and the sheet pressing member 111 will be described later.

  The booklet SSS produced by cutting the fore edge SSa is placed on the reversely rotating transport belt 83 and transported in a state where the rear end portion of the booklet SSS is pressed by the movable alignment member 84 fixed to the transport belt 83. Then, it falls in the direction of the arrow from the tip of the conveyor belt 83. The fallen booklet SSS is discharged to a discharge tray 86 disposed outside the front side Bf of the post-processing apparatus B by a rotating discharge belt 85.

  A cutting waste processing unit 190 is disposed below the booklet transport unit 80 and the sheet cutting apparatus 100. The cutting waste cut from the edge portion SSa by the paper cutting device 100 is dropped and transferred onto the rotating cutting waste transport belt 191 and is stored in the cutting waste container 192.

  In the present embodiment, the sheet cutting apparatus 100 of the post-processing apparatus B having the function of half-folding and saddle stitching connected to the copying machine body has been described. It is also applicable to the device. Alternatively, the post-processing apparatus B may be a sheet bundle manufacturing apparatus such as a glue binding apparatus.

  It is also possible to selectively connect a post-processing apparatus B equipped with the sheet cutting apparatus 100 of the present invention to a bookbinding apparatus connected to a light printing machine so that multi-purpose and multi-function post-processing can be processed consistently. It is. The same effect can be obtained by applying to a post-processing apparatus that is used by connecting to the image forming apparatus A such as a light printing machine, a printer, a facsimile machine, or a multifunction machine.

<Paper cutting apparatus 100>
FIG. 4 is a diagram illustrating the sheet cutting apparatus 100 in the post-processing apparatus B.

  4A is a front view, FIG. 4B is a side view of the main part, and FIG. 4C is a top view of the main part.

  4A, 4B, and 4C, a pressing unit 110 having a sheet pressing member 111 that functions as a sheet pressing unit is provided at the upper part of the sheet cutting apparatus 100, and is cut at the lower part of the main body. A cutting part 130 having a blade 131 is arranged. Reference numeral 140 denotes a reverse motion prevention unit 140.

  The sheet cutting apparatus 100 shown in the figure is in a standby state and a sheet bundle SS is introduced. Here, the standby state refers to a state in which the paper pressing member 111 has been moved to the standby position that is the upper limit position.

  Reference numeral 137 denotes a fixed mounting table disposed in the cutting unit 130, which functions as a paper mounting unit. The sheet bundle SS that has been saddle-stitched and that has been spread apart is introduced into the sheet cutting apparatus 100, and the fore edge portion SSa thereof is placed on the placement table 137. The sheet bundle SS placed on the placing table 137 is pressed by the sheet pressing member 111 that descends in the arrow Z direction from the standby position. A two-dot chain line in the drawing indicates the paper pressing member 111 at a position for pressing the paper bundle SS. The small bundle SSa of the sheet bundle SS pressed by the sheet pressing member 111 is cut by the cutting blade 131 that is moved obliquely upward from the illustrated position in the direction indicated by the arrow C.

  The reverse motion prevention unit 140 prevents the paper pressing member 111 from being pushed back from a position where it presses the paper bundle SS while the paper bundle is cut (hereinafter also referred to as reverse motion). Due to the action of the reverse movement prevention unit 140, the sheet pressing member 111 continues to be pressed against the sheet bundle SS while the fore edge SSa of the sheet bundle SS is cut, so that the sheet bundle SS may be displaced from the placed position. There is no cutting and no cutting is disturbed.

<Pressing part 110>
The sheet pressing member 111 of the pressing unit 110 is moved in the direction indicated by the arrow Z by the driving force of the pressing driving motor M1 that functions as a pressing driving force generating unit transmitted by the pressing moving unit 120, and is placed on the mounting table on the lower surface thereof. The sheet bundle SS placed on 137 is pressed. The left and right side surfaces of the paper pressing member 111 have protrusions 111sA and 111sB formed with female threads, respectively. The protrusions 111sA and 111sB will be described later.

  The pressing movement unit 120 includes a belt reduction mechanism 121 that transmits the rotational driving force of the pressing drive motor M <b> 1 at a reduced speed, and a screw pressing unit 129.

  The belt reduction mechanism 121 includes a first pulley 122 that functions as a driving pulley that is rotated by a pressing drive motor M1, a second pulley 123 and third pulleys 124A and 124B that function as driven pulleys, a first pulley 122, and a second pulley. The first drive belt 125, the second pulley 123, and the second pulleys 124A, 124B spanned between the first and third pulleys 124A, 124B. The rotation of the pressing drive motor M1 is decelerated and transmitted to the third pulleys 124A and 124B by the belt reduction mechanism 121.

  The screw pressing portion 129 includes a projecting portion 111sA and 111sB functioning as a female screw portion and a rotating shaft 129sA having a male screw threadedly engaged with a screw of the projecting portion 111sA functioning as a male screw portion. 129 sB. Then, by rotating the rotation shafts 129 sA and 129 sB, the protrusions 111 sA and 111 sB are converted into movements in the axial direction of the rotation shafts 129 sA and 129 sB, and the sheet pressing member 111 having the protrusions 111 sA and 111 sB is disposed on the sheet. It moves in the direction approaching or separating from the mounting part. Whether the paper pressing member 111 approaches or separates from the mounting table 137 is determined by switching the rotation direction of the pressing drive motor M1.

  The first pulley 122 in the belt reduction mechanism 121 is attached to the output shaft of the pressing drive motor M1, and is rotated by the rotation of the pressing drive motor M1.

  The second pulley 123 includes a large pulley portion 123c having a larger outer diameter than the first pulley 122, a small pulley portion 123a and a small pulley portion 123b each having the same outer diameter smaller than the large pulley portion 123c. These pulleys have a three-layer structure in which the respective rotation centers coincide with each other and are rotatably supported by a support means (not shown).

  The third pulleys 124A and 124B are pulleys having the same outer diameter, and each outer diameter is larger than the outer diameters of the small pulley portion 123a and the small pulley portion 123b in the second pulley 123. The third pulleys 124A and 124B are rotatably supported by support means (not shown).

  Each of the first drive belt 125 and the second drive belts 126A, 126B is an endless belt formed of a so-called rubber-based material such as CR rubber, for example.

  The first drive belt 125 is stretched between the first pulley 122 and the large pulley portion 123 c of the second pulley 123. As described above, since the outer diameter of the large pulley portion 123 c of the second pulley 123 is larger than the outer diameter of the first pulley 122, the rotation of the first pulley 122 is decelerated and transmitted to the second pulley 123.

  The second drive belt 126A is stretched around the small pulley portion 123a of the second pulley 123 and the third pulley 124A. As described above, since the outer diameter of the third pulley 124A is larger than the outer diameter of the small pulley portion 123a of the second pulley 123, the rotation of the second pulley 123 is decelerated and transmitted to the third pulley 124A.

  A small gear 127A is attached to the third pulley 124A so that the rotation center thereof coincides with that of the third pulley 124A. The small gear 127A rotates integrally with the third pulley 124A.

  The second drive belt 126B is stretched around the small pulley portion 123b of the second pulley 123 and the third pulley 124B. Since the small pulley portion 123b of the second pulley 123 has the same outer diameter as the small pulley portion 123a, and the third pulley 124B has the same outer diameter as the third pulley 124A, the rotation of the second pulley 123 causes the third pulley 124B to It rotates in the same direction at the same rotational speed as the three pulleys 124A.

  A small gear 127B is attached to the third pulley 124B so that the center of rotation coincides with the third pulley 124B. The small gear 127B rotates integrally with the third pulley 124B.

  Reference numerals 129sA and 129sB denote rotation axes. The rotation shafts 129sA and 129sB are shaft members each having a male screw formed on the outer periphery of the rod body. The external threads formed on the rotary shafts 129sA and 129sB of the present embodiment are trapezoidal screws having a trapezoidal cross-sectional shape of the thread, and the direction of the screw is a right-handed screw and has the same lead. The rotation shafts 129sA and 129sB are supported by a non-illustrated support means so that the upper and lower ends of the rotation shafts are parallel to the moving direction of the paper pressing member 111 (in the direction of the arrow Z in the figure) and can be freely rotated. Is supported in an unacceptable state.

  The sheet pressing member 111 has a protruding portion 111sA on the left side in the figure and a protruding portion 111sB on the right side. Female threads (trapezoidal screws) that can be screwed onto the screws formed on the rotation shafts 129sA and 129sB are formed on the protrusions 111sA and 111sA, respectively.

  The paper pressing member 111 is incorporated by screwing the protruding portions 111sA and 111sB to the rotation shafts 129sA and 129sB, respectively.

  When the rotary shafts 129sA and 129sB are rotated simultaneously, the axial movements of the rotary shafts 129sA and 129sB are not allowed. The pressing member 111 is moved along the rotation shafts 129sA and 129sB.

  A large gear 128A that meshes with the small gear 127A is attached to an upper portion of the rotation shaft 129sA and a position opposite to the small gear 127A. The rotation shaft 129sA is rotated by the rotation of the small gear 127A, that is, the pressing drive motor M1. The rotation of the third pulley 124A causes the rotation in the direction opposite to the rotation direction of the third pulley 124A.

  Similarly, a large gear 128B that meshes with the small gear 127B is attached to an upper portion of the rotation shaft 129sB and a position opposite to the small gear 127B. The rotation shaft 129sB is rotated by the rotation of the small gear 127B, that is, by the pressing drive motor M1. The rotation of the third pulley 124B is rotated in the direction opposite to the rotation direction of the third pulley 124B.

  Therefore, by rotating the pressing drive motor M1, the rotating shaft 129sA and the rotating shaft 129sB are rotated, and the sheet pressing member 111 can be moved in the arrow Z direction.

  As described above, the screws formed on the rotary shafts 129sA and 129sB are right-hand screws having the same lead size. Therefore, when the rotation shafts 129sA and 129sB are respectively viewed from the upper end side, that is, when viewed from the side of FIG. 4C, the protrusions are screwed into the rotation shafts 129sA and 129sB, respectively, when rotated clockwise. The portions 111sA and 111sB are moved to the upper end side of the rotation shafts 129sA and 111sB. That is, the paper pressing member 111 provided with the protruding portions 111sA and 111sB is moved upward. On the other hand, when the rotary shafts 129sA and 129sB are rotated in the counterclockwise direction when viewed from the side of FIG. 4C, the protrusions 111sA and 111sB screwed to the rotary shafts 129sA and 129sB are moved downward, and the paper pressing member 111 is moved downward.

  The rotation shafts 129sA and 129sB are connected to the third pulleys 124A and 124B of the belt reduction mechanism 121 via the large gear 128A, the small gears 127A and 128B, and the small gear 127B, respectively. 4C, the sheet pressing member 111 is moved upward when rotated counterclockwise, and the sheet pressing member 111 is moved downward when rotated clockwise.

  The arrows r1A and r1B shown in FIG. 4C are the rotation directions of the large gear 128A and the large gear 128B that lower the paper pressing member 111, and the arrows r2, r3, r4A, and r4B are the paper pressing members, respectively. The rotation direction of the first pulley 122, the second pulley 123, and the third pulleys 124A and 124B in the belt reduction mechanism 121 that lowers 111.

  Therefore, in order to lower the paper pressing member 111, the first pulley 122 may be rotated in the direction of the arrow r2 by the pressing drive motor M1 in order to rotate the rotation shafts 129sA and 129sB in the directions of the arrows r1A and r1B. Further, in order to raise the sheet pressing member 111, the first pulley 122 is rotated in the direction opposite to the arrow r2 by the pressing drive motor M1 in order to rotate the rotating shafts 129sA and 129sB in the direction opposite to the arrows r1A and r1B. You can do it.

  When the paper pressing member 111 is moved by a force other than the driving force of the pressing drive motor M1, the rotation shafts 129sA and 129sB that are screwed into the protruding portions 111sA and 111sB of the moved paper pressing member 111 are rotated. . The rotations of the rotation shafts 129sA and 129sB are transmitted to the third pulleys 124A and 124B of the belt reduction mechanism 121 via the small gear 127A that meshes with the large gear 128A and the small gear 127B that meshes with the large gear 128B, respectively. . The rotation of the third pulleys 124A and 124B is transmitted to the second pulley 123 via the second drive belts 126A and 126B, and the rotation of the second pulley 123 is transmitted to the first pulley 122 via the first drive belt 125. Is done.

  These rotary shafts 129sA and 129sB, the large gear 128A and the small gear 127A, the large gear 128B and the small gear 127B, the third pulley 124A and 124B, the second pulley 123, the first pulley 122, and the second drive belts 126A and 126B. The first driving belt 125 is a member that is moved by the moved paper pressing member 111 when the paper pressing member 111 is moved, that is, a member that is driven by the movement of the paper pressing member 111.

  For example, when the paper pressing member 111 is moved downward, the large gears 128A and 128B that rotate with the rotation shafts 129sA and 129sB are rotated in the directions of the arrows r1A and r1B with the small gears 127A and 127B. 124A and 124B are driven to rotate in the directions of arrows r4A and r4B, the second pulley 123 is driven to rotate in the direction of arrow r3, and the first pulley 122 is driven to rotate in the direction of arrow r2.

  For example, when the paper pressing member 111 is moved upward, the large gears 128A and 128B rotating together with the rotation shafts 129sA and 129sB are rotated together with the small gears 127A and 127B in the direction opposite to the arrows r1A and r1B. The three pulleys 124A and 124B are driven to rotate in the direction opposite to the arrows r4A and r4B, the second pulley 123 is rotated in the direction opposite to the arrow r3, and the first pulley 122 is driven to rotate in the direction opposite to the arrow r2.

<Cutting section 130>
The cutting unit 130 includes a cutting blade 131 having a cutting edge formed on the upper edge and a mounting table 137.

  The cutting blade 131 has two long holes 131hA and 131hB that are inclined in parallel. Cutting blade holding shafts 138A and 138B are arranged on the front surface of the mounting table 137, and the cutting blade 131 is held by inserting elongated holes 131hA and 131hB into the cutting blade holding shafts 138A and 138B, respectively.

  The cutting blade 131 is movable in a slanting vertical direction by two elongated holes 131hA and 131hB arranged in an inclined manner and cutting blade holding shafts 138A and 138B.

  The illustrated cutting unit 130 is in a state where the cutting blade 131 is in the standby position, which is the lowest position.

  The cutting blade drive motor M2 as a drive source is a drive motor that moves the cutting blade 131. The cutting blade 131 at the standby position is moved obliquely in the up-down direction and the arrow C direction by the cutting blade drive motor M2, and the sheet bundle SS placed on the placement table 137 is moved by the blade tip disposed on the upper edge. Cut the small edge SSa.

<Reverse motion prevention unit 140>
The reverse motion prevention unit 140 operates at a predetermined timing in conjunction with the operation of the sheet cutting device 100. When the reverse motion prevention unit 140 is operated, the brake pad 143 attached to the brake lever 142 and functioning as a braking unit is connected to the second pulley 123. When the paper pressing member 111 is moved in the direction opposite to the direction in which the sheet bundle SS is pressed (hereinafter referred to as reverse movement), the second pulley 123 is brought into contact with and pressed against the wound first driving belt 125. Is prevented from being driven to rotate. The component that the brake pad 143 contacts and presses may be any component that is driven by the movement of the sheet pressing member 111 in the pressing moving unit 120, but the first drive belt 125 that winds the second pulley 123 and the like. By doing so, it is possible to prevent the second pulley 123 from being driven by a small pressing force, and to prevent the paper pressing member 111 from being reversely moved.

  Hereinafter, the back motion prevention unit 140 will be described.

  FIG. 5 is a diagram illustrating the back movement prevention unit 140. FIG. 5A is a diagram illustrating when the brake pad 143 of the reverse movement preventing unit 140 is in the second position, and FIG. 5B is a diagram illustrating when the brake pad 143 is in the first position.

  As shown in FIGS. 5A and 5B, the reverse motion prevention unit 140 includes a brake lever 142, a brake pad 143, a support shaft 144, a tension spring 145, and a solenoid 146.

  The brake pad 143 is formed of a so-called rubber material such as urethane rubber, and is fixed to one end of the brake lever 142.

  The brake lever 142 is swingably disposed around a support shaft 144 fixed to a support shaft fixing portion (not shown).

  The tension spring 145 is attached to the end of the brake lever 142 opposite to the brake pad 143 attachment position with the support shaft 144 interposed therebetween. Then, the brake lever 142 is biased in a direction in which the brake pad 143 fixed to the brake lever 142 is separated from the second pulley 123 with the support shaft 144 as a rotation center.

  The solenoid 146 is a pull-type solenoid that is operated by electric power supplied from a driving power source (not shown) and that is pulled into the solenoid body 146B when energized. Then, the tension spring 145 in the brake lever 142 is connected to the end of the plunger 146P so as to be swingable in the vicinity of the mounting position with the support shaft 144 interposed therebetween.

  When the solenoid 146 is energized, it is the first position of the brake pad 143 of the reverse movement prevention unit 140, and when it is not energized is the second position of the brake pad 143, FIG. These are figures which show when the brake pad 143 of the back movement prevention part 140 exists in the 2nd position by which electricity supply to the solenoid 146 is not made. When the solenoid 146 is not energized, the brake pad 143 fixed to the tip of the brake lever 142 biased by the tension spring 145 moves to a position away from the first drive belt 125 around which the second pulley 123 is wound. Is done.

  At this time, the plunger 146P of the position solenoid 146 separated from the first drive belt 125 around which the second pulley 123 is wound is pulled out of the solenoid body 146B by the urging force of the tension spring 145.

  FIG. 5B is a diagram illustrating a state where the brake pad 143 of the reverse movement preventing unit 140 is in the first position where the solenoid 146 is energized. When the solenoid 146 is energized, a suction force acts on the plunger 146P and is drawn into the solenoid body 146B. Then, the brake lever 142 connected to the plunger 146P is moved toward the solenoid body 146B against the urging force of the tension spring 145. As the brake lever 142 moves toward the solenoid body 146B, the brake lever 142 is rotated clockwise around the support shaft 144, and the brake pad 143 fixed to the tip of the brake lever 142 is wound around the second pulley 123. It abuts on the rotated first drive belt 125 and further presses it.

  When the brake pad 143 of the reverse motion prevention unit 140 is in the first position, for example, the first drive belt 125 formed of CR rubber is pressed by the brake pad 143 formed of urethane rubber, for example. A large frictional force that prevents relative movement between the first drive belt 125 and the brake pad 143 is applied to the contact portion between the first drive belt 125 and the brake pad 143. Therefore, when the brake pad 143 is in the first position, the movement of the first drive belt 125 pressed against the brake pad 143 is blocked, and the rotation of the second pulley 123 around the first drive belt 125 is blocked. The

  The reverse motion prevention unit 140 operates in conjunction with the operation of the sheet cutting apparatus 100.

  Next, the operation of the sheet cutting apparatus 100 and the operation of the backlash prevention unit 140 associated with the operation will be described.

  While the sheet cutting device 100 waits for the introduction of the sheet bundle SS, as shown in FIG. 4, the sheet pressing member 111 is at the upper movement limit position that is the standby position, and the cutting blade 131 is at the lower movement limit position that is the standby position. Waiting. Further, the reverse motion prevention unit 140 is in a standby state in which the solenoid 146 is not energized and the brake pad 143 is in the second position separated from the first drive belt 125.

  When the sheet bundle SS is introduced into the sheet cutting apparatus 100 and placed on the mounting table 137, the pressing drive motor M1 in the pressing unit 110 is activated to lower the sheet pressing member 111 from the standby position. At this time, since the brake pad 143 is in the second position, the back movement prevention unit 140 does not become a load of the pressing drive motor M1 that lowers the sheet pressing member 111.

  The pressing drive motor M1 stops when the lowered sheet pressing member 111 comes into contact with the sheet bundle SS on the mounting table 137 and further presses the sheet bundle SS on the mounting table 137 with a predetermined amount of force.

  Whether or not the sheet pressing member 111 has pressed the sheet bundle SS with a predetermined amount of power is determined by the current value of the electric power supplied to the pressing drive motor M1. That is, the current of the electric power supplied to the pressing drive motor M1 to lower the paper pressing member 111 while the lowering paper pressing member 111 is approaching the paper bundle SS or until the paper pressing member 111 comes into contact with the paper bundle SS and starts pressing. The value remains at a low level. However, when pressing is started in contact with the sheet bundle SS, the pressing drive motor M1 lowers the sheet pressing member 111 against the repulsive force against the pressing of the sheet bundle SS, so that the current value increases as the pressing proceeds. Increase. In the sheet cutting apparatus 100 according to the present embodiment, a current value when the sheet pressing member 111 presses the sheet bundle SS with a predetermined pressing force is obtained, and the sheet pressing member 111 is pressed when the sheet pressing member 111 is lowered. When the current value of the power supplied to the drive motor M1 reaches the current value determined in advance, the power supply to the pressing drive motor M1 is stopped. Here, the predetermined pressing force with which the sheet pressing member 111 presses the sheet bundle SS is a force applied by the cutting blade 131 when the small edge SSa of the sheet bundle SS is cut by the cutting blade 131. The pressing force is a level at which the setting position is not shifted, and is determined in advance in consideration of the characteristics of the paper, the sharpness of the cutting blade 131, the moving speed of the cutting blade 131 during cutting, and the like.

  Note that the stop position of the sheet pressing member 111 may be set by calculating the thickness of the sheet bundle from the number of sheets forming the sheet bundle SS regardless of the current value of the power supplied to the pressing drive motor M1. .

  Along with the stop of the pressing drive motor M1, the reverse movement prevention unit 140 operates, and the solenoid 146 is energized. By energizing the solenoid 146, the plunger 146 </ b> P pulls the brake lever 142 against the bias of the tension spring 145, and moves to the first position where the brake pad 143 contacts and presses the first drive belt 125. The second pulley 123 is prevented from rotating by the contact and pressing of the brake pad 143 moved to the first position with the first drive belt 125.

  When the rotation of the second pulley 123 is blocked by the brake pad 143 at the first position, the cutting blade drive motor M2 is operated, and the cutting blade 131 at the standby position is moved and pressed by the paper pressing member 111. Cut the edge of the sheet bundle SS.

  The sheet bundle SS cut by the cutting blade 131 is subjected to a force that pushes back the sheet pressing member 111 to be pressed, that is, reversely moves. The force to reversely move the paper pressing member 111 is a force to follow and rotate the rotation shafts 129sA and 129sB that are screwed into the protruding portions 111sA and 111sB of the paper pressing member 111, and the third pulleys 124A and 124B. Is transmitted as a force to rotate the second pulley 123 via.

  However, since the rotation of the second pulley 123 is prevented by the brake pad 143 in the first position, the second pulley 123 is not rotated and the sheet pressing member 111 is not moved backward. Therefore, the sheet pressing member 111 stays at a position where the sheet bundle SS is pressed with a predetermined pressing force and continues to press. Therefore, the sheet bundle SS may be displaced during cutting and the cut edge may be disturbed. Absent.

  When the cutting is completed, the cutting blade drive motor M2 rotates in the reverse direction and lowers the cutting blade 131 to the standby position.

  When the lowering of the cutting blade 131 is completed, the energization to the solenoid 146 is stopped.

  When the energization of the solenoid 146 is stopped, the brake lever 142 is pulled by the urging force of the tension spring 145, and the brake pad 143 that has been in contact with and pressed against the first drive belt 125 at the first position is It is moved to a second position away from the drive belt 125. Therefore, the second pulley 123 is released from the prevention of the rotation made by the brake pad 143.

  When the second pulley 123 is released from the prevention of rotation by the brake pad 143, the pressing drive motor M1 rotates in the direction opposite to the pressing operation direction to raise the sheet pressing member 111.

  As the sheet pressing member 111 is raised, the sheet bundle SS is released from being pressed by the sheet pressing member 111. Then, the sheet pressing member 111 is raised to the standby position, and a series of cutting operations is completed.

  In this way, during cutting, the brake pad 143 in the first position prevents the rotation of the second pulley 123, so that the sheet pressing member 111 is not moved backward and is positioned to press the sheet bundle SS with a predetermined pressing force. Since the sheet stays and continues to be pressed, the sheet bundle SS is not shifted during cutting, and the cut edge is not disturbed. The energy required for the sheet pressing member 111 to continue pressing the sheet during cutting is only the power supplied to the solenoid 146, and does not require large power.

  Further, as described above, the pressing movement unit 120 decelerates the rotation of the pressing drive motor M1 and transmits it to the paper pressing member 111. Therefore, when the paper pressing member 111 is reversely moved, The movement is converted into the increased rotation of the second pulley 123. Therefore, a large force is not required to prevent the rotation of the second pulley 123 so that the paper pressing member 111 is not moved backward, and the power supplied to the solenoid 146 may be small.

  Further, since a trapezoidal screw is used for the screw pressing portion 129, the conversion efficiency in which the reverse movement of the paper pressing member 111 is converted into the driven rotation of the rotation shafts 129sA and 129sB is low, and the rotation of the rotation shafts 129sA and 129sB is low. In order to prevent the rotation of the second pulley 123 that is rotated, the second pulley 123 may be pressed with a small amount of force. Therefore, the suction force of the solenoid 146 for preventing the rotation of the second pulley 123 can be further reduced, and the power supplied to the solenoid 146 can be reduced.

  The post-processing apparatus described above presses the first drive belt that winds the second pulley, which is one of the parts driven by the reverse movement of the paper pressing member, with the brake pad to prevent the follower from being cut. This prevents the sheet pressing member from being reversely moved during operation.

  The post-processing apparatus described below is an embodiment different from the above-described post-processing apparatus, and the second pulley, which is one of the parts that follow the reverse movement of the paper pressing member during the cutting operation of the paper cutting apparatus 100. The engaging portion is engaged with the to-be-engaged portion disposed on the paper pressing member to prevent the sheet pressing member from being reversely moved.

<Paper cutting apparatus 100>
FIG. 6 shows that during the cutting operation, the paper pressing member is reversely moved by engaging the locked portion disposed on the second pulley, which is one of the parts driven by the reverse movement of the paper pressing member. It is a figure explaining the paper cutting apparatus which has a reverse motion prevention part which prevents that.

  6A is a front view, FIG. 6B is a side view of the main part, and FIG. 6C is a top view of the main part.

  As shown in FIGS. 6A, 6B, and 6C, a pressing portion 110 having a paper pressing member 111 is disposed at the upper portion of the paper cutting device 100, and a cutting blade 131 is provided at the lower portion of the main body. Part 130 is arranged. Reference numeral 150 denotes a back motion prevention unit. The reverse motion prevention unit 150 includes a ratchet wheel 157 that functions as a locked portion on the second pulley 123, and a ratchet pawl 152 that functions as a locking portion is engaged with the ratchet wheel 157 to reverse the paper pressing member 111. The driven rotation of the second pulley 123 that accompanies the movement is prevented, and the reverse movement of the paper pressing member 111 during the cutting operation is prevented.

  The sheet cutting apparatus 100 shown in the figure is in a standby state and a sheet bundle SS is introduced.

  Reference numeral 137 denotes a fixed mounting table disposed in the cutting unit 130, and the sheet bundle SS that has been saddle-stitched and closed in a spread state introduced into the sheet cutting apparatus 100 has its fore edge SSa mounted on the mounting table 137. The The sheet bundle SS placed on the placing table 137 is pressed by a sheet pressing member 111 that functions as a sheet pressing portion that descends in the direction of arrow Z from the illustrated standby position. A two-dot chain line in the drawing indicates the paper pressing member 111 at a position for pressing the paper bundle SS. The small bundle SSa of the sheet bundle SS on the mounting table 137 pressed by the sheet pressing member 111 is cut by the cutting blade 131 that is moved obliquely upward from the illustrated standby position in the direction of the arrow C illustrated. The reverse motion prevention unit 150 prevents the paper pressing member 111 from being pushed back from the position where it presses the paper bundle SS while the paper bundle is cut, that is, the reverse motion is prevented. Due to the action of the reverse movement preventing unit 150, the sheet pressing member 111 is continuously pressed against the sheet bundle SS while the fore edge SSa of the sheet bundle SS is cut, so that the sheet bundle SS does not deviate from the loading position. , Cutting is done without disrupting the cut.

  6A, 6B, and 6C, the pressing unit 110, the pressing moving unit 120, and the cutting unit 130 of the sheet cutting apparatus 100 shown in FIGS. 4A, 4B, and 4C, respectively. Components having the same configuration and operation as those of the pressing unit 110, the pressing moving unit 120, and the cutting unit 130 in the sheet cutting apparatus 100 described with reference to c) are denoted by the same reference numerals. . Therefore, the description of the pressing unit 110, the pressing moving unit 120, and the cutting unit 130 is omitted to avoid duplication with the description using FIGS. 4A, 4B, and 4C. Hereinafter, the back motion prevention unit 150 will be described in detail.

<Reverse motion prevention unit 150>
The reverse motion prevention unit 150 operates in two modes, a first mode and a second mode, which will be described later, at a predetermined timing linked to the operation of the sheet cutting apparatus 100.

  Hereinafter, the back motion prevention unit 150 will be further described.

  FIG. 7 is a diagram illustrating the back movement prevention unit 150. FIGS. 7A and 7B show the case where the back movement prevention unit 150 is in the first mode state, and FIG. 7C shows the case where the back movement prevention unit 150 is in the second mode state. FIG. FIG. 7B is a diagram for explaining the operation of the ratchet pawl 152 when the back movement prevention unit 150 is in the first mode state.

  When the reverse motion preventing unit 150 is in the first mode state, the ratchet pawl 152 biased by the tension spring 155 is engaged with the ratchet wheel 157 fixed to the second pulley 123, and the second pulley 123 Only rotation in the direction of lowering the paper pressing member 111 is allowed.

  In the second mode state, the ratchet pawl 152 is separated from the ratchet wheel 157, and the second pulley 123 is allowed to rotate in the direction in which the paper pressing member 111 is raised.

  As shown in FIGS. 7A, 7 </ b> B, and 7 </ b> C, the reverse motion preventing unit 150 includes a ratchet pawl 152, a support shaft 154, a tension spring 155, a solenoid 156, and a ratchet wheel 157.

  The ratchet wheel 157 has a gentle slope where the distance from the outer peripheral surface of the disk gradually increases on the outer periphery of the disk, and a distance from the center of the disk on the gentle slope toward the outer peripheral surface of the disk. The claw wheel is formed by continuously forming a plurality of engaging teeth having a saw-tooth shape composed of a steep slope whose distance decreases rapidly. The ratchet wheel 157 is fixed to the second pulley 123 with the same center as the second pulley 123. The ratchet wheel 157 is fixed to the second pulley 123 at the same time when the second pulley 123 is rotated in the direction of the arrow r3 in the figure, which is the rotation direction of the second pulley 123 when the paper pressing member 111 is lowered. The gentle slope side of the engaging tooth which forms the sawtooth shape of the ratchet wheel 157 is in the direction leading the rotation. In addition, although the number of engagement teeth of the ratchet wheel 157 in this Embodiment is 12, it is not limited to this.

  The ratchet pawl 152 has a tip pawl portion 152 c, and the tip pawl portion 152 c is in a position engageable with the engagement tooth of the ratchet wheel 157 fixed to the second pulley 123, and a support shaft fixing portion (not shown). The support shaft 154 fixed to the support shaft 154 is supported so as to be rotatable.

  The tension spring 155 is attached to the end of the ratchet pawl 152 opposite to the tip pawl 152c across the support shaft 154. Then, the ratchet pawl 152 is urged so as to rotate the tip pawl portion 152c toward the ratchet wheel 157, that is, clockwise, with the support shaft 154 as the center of rotation.

  The solenoid 156 is a push-out type solenoid in which the plunger 156P protrudes from the solenoid body 156B when energized by operating with electric power supplied from a drive power source (not shown). Then, the end of the plunger 156P is disposed in the vicinity of the attachment position of the tension spring 155 on the ratchet pawl 152 with the support shaft 154 interposed therebetween.

  When the solenoid 156 is energized, the plunger 156P protruding from the solenoid body 156B presses the ratchet pawl 152 urged clockwise by the tension spring 155 and rotates it counterclockwise. This state in which the solenoid 156 is energized is a state in which the back movement prevention unit 150 is in the second mode.

  Further, when the solenoid 156 is not energized, the plunger 156P does not press the ratchet pawl 152, so that the ratchet pawl 152 described later is not inhibited from swinging. This state where the solenoid 156 is not energized is a state where the back movement prevention unit 150 is in the first mode.

  The reverse movement prevention unit 150 performs solenoid cutting of the sheet bundle SS introduced into the sheet cutting apparatus 100 and raises the sheet pressing member 111 from the position where the sheet bundle SS is pressed to the standby position. In a second mode state in which current is supplied to the solenoid 156, otherwise, the solenoid 156 is not supplied with current in a first mode state.

  FIG. 6A is a diagram when the back movement prevention unit 150 is in the first mode, that is, when the solenoid 156 is not energized. Since the solenoid 156 is not energized, the plunger 156P does not press the ratchet pawl 152, and the tip pawl portion 152c of the ratchet pawl 152 that is urged clockwise by the tension spring 155 is the engagement tooth of the ratchet wheel 157. Abut.

  When the back movement preventing portion 150 is in the first mode state, the tip claw portion 152c of the ratchet claw 152 biased by the tension spring 155 rotates in the same direction when the second pulley 123 is rotated in the arrow r3 direction. The ratchet wheel 157 of the ratchet wheel 157 contacts the gentle slope and the steep slope of the engaging teeth in order. The ratchet pawl 152 swings the support shaft 154 because it repeatedly contacts the gentle slope from the bottom of the engaging tooth and reaches the bottom of the tooth along the steep slope when it reaches the maximum outer peripheral portion of the gentle slope. Swing around the center. The rotation of the second pulley 123 in the direction of the arrow r3 is a rotation in the direction in which the paper pressing member 111 is lowered.

  FIG. 7B is a diagram illustrating the swinging of the ratchet pawl 152 when the reverse movement preventing unit 150 is in the first mode, and the arrow S indicates the swinging range of the ratchet pawl 152.

  As described above, when the second pulley 123 is rotated in the direction of the arrow r3, that is, when the second pulley 123 is rotated in the direction in which the paper pressing member 111 is lowered, the ratchet pawl 152 swings around the support shaft 154 as the swing center. The rotation of the second pulley 123 in the direction of the arrow r3 is not hindered.

  However, when the second pulley 123 is rotated in the direction opposite to the arrow r3 direction, that is, when the second pulley 123 is rotated in the direction in which the paper pressing member 111 is lowered, the ratchet pawl 152 biased by the tension spring 155 When the tip claw portion 152c comes into contact with the tooth bottom of the ratchet wheel 157, the tip claw portion 152c cannot stay over the steep slope of the engaging tooth having a sawtooth shape and stays on the tooth bottom of the ratchet wheel 157, and is engaged with the ratchet wheel 157. Match. Therefore, the ratchet pawl 152 engaged with the ratchet wheel 157 prevents the second pulley 123 from rotating in the direction opposite to the arrow r3 direction.

  As described above, when the back movement prevention unit 150 is in the first mode, the rotation of the second pulley 123 in the direction of the arrow r3, that is, the rotation in the direction of lowering the paper pressing member 111 is allowed, but the opposite is true. Rotation in the direction is prevented.

  FIG. 7C is a diagram illustrating a state in which the back movement prevention unit 150 is in the second mode, that is, a state in which the solenoid 156 is energized.

  When the solenoid 156 is energized, the plunger 156P protrudes from the solenoid body 156B and abuts against the ratchet pawl 152, moves the ratchet pawl 152 against the biasing force of the tension spring 155, and moves the tip pawl portion 152c to the ratchet. Separate from the car 157.

  Due to the separation of the tip claw portion 152c from the ratchet wheel 157, the ratchet wheel 157 is not engaged with the ratchet wheel 152, and the ratchet wheel 157 rotates in either the clockwise direction or the counterclockwise direction, that is, The paper pressing member 111 can be rotated in any direction that lowers or raises the paper pressing member 111.

  Next, the operation of the sheet cutting apparatus 100 and the operation of the reverse motion prevention unit 150 accompanying the operation will be described.

  While the sheet cutting device 100 waits for the introduction of the sheet bundle SS, as shown in FIG. 6, the sheet pressing member 111 is waiting at the upper limit position and the cutting blade 131 is waiting at the lower limit position. At this time, the reverse motion prevention unit 150 is in the first mode state in which the solenoid 156 is not energized, and the tip pawl portion 152c of the ratchet pawl 152 is in a position where it can engage with the ratchet wheel 157.

  When the sheet bundle SS is introduced into the sheet cutting apparatus 100 and placed on the mounting table 137, the pressing drive motor M1 in the pressing unit 110 is activated, and the sheet pressing member 111 is lowered from the standby position. At this time, the ratchet wheel 157 is allowed to rotate in the direction in which the paper pressing member 111 is lowered by the ratchet pawl 152 in the first mode state, and does not prevent the paper pressing member 111 from being lowered.

  The pressing drive motor M1 stops when the sheet pressing member 111 comes into contact with the sheet bundle SS on the mounting table 137 and further presses the sheet bundle SS on the mounting table 137 with a predetermined pressing force.

  In the present embodiment, when the current value of the power supplied to the pressing drive motor M1 reaches a predetermined current value, the power supply to the pressing drive motor M1 is stopped and the pressing drive motor M1 is stopped.

  When the pressing drive motor M1 stops, the cutting blade drive motor M2 operates to move the cutting blade 131 at the standby position, and cut the edge of the sheet bundle SS.

  A force in the direction of pushing back the paper pressing member 111 to be pressed, that is, a force that reversely moves acts on the paper bundle SS cut by the cutting blade 131. This force is a force that rotates the rotation shafts 129sA and 129sB that are screwed into the protrusions 111sA and 111sB of the paper pressing member 111, and further, the second pulley 123 is moved via the third pulleys 124A and 124B to the arrow r3. It is transmitted as a force that is driven to rotate in the opposite direction.

  However, the reverse motion prevention unit 150 is in the first mode state, and the follower rotation of the ratchet wheel 157 in the direction opposite to the arrow r3 is prevented by the ratchet pawl 152 engaged with the ratchet wheel 157. The two pulleys 123 are not driven to rotate, and the sheet pressing member 111 is not moved backward.

  Therefore, the sheet pressing member 111 stays at the position where the sheet bundle SS is pressed with a predetermined pressing force and continues to press, so that the sheet bundle SS is displaced during cutting and the cut edge is disturbed. There is no.

  When the cutting is completed, the cutting blade drive motor M2 rotates in the reverse direction and lowers the cutting blade 131 to the standby position.

  When the lowering of the cutting blade 131 is completed, the solenoid 156 is energized, and the back movement prevention unit 150 enters the second mode state. When the solenoid 156 is energized, the plunger 156P of the solenoid 156 protrudes from the solenoid body 156B, and the protruding plunger 156P counteracts the ratchet pawl 152 against the bias of the tension spring 155 and the support shaft 154 as the center of rotation. Rotate in the direction.

  As the ratchet pawl 152 rotates counterclockwise, the tip pawl portion 152 c that is in a position that can be engaged with the ratchet wheel 157 is separated from the ratchet wheel 157.

  The separation of the tip claw portion 152c from the ratchet wheel 157 releases the rotation of the ratchet wheel 157 in the direction opposite to the arrow r3 made by the tip claw portion 157c, and the second pulley 123 is moved to the sheet pressing member 111. It is possible to rotate in the direction of raising.

  When the reverse movement prevention unit 150 is in the second mode state, the pressing drive motor M1 rotates in the direction opposite to the pressing operation direction to raise the sheet pressing member 111.

  The sheet bundle SS is released from being pressed by the rising of the sheet pressing member 111. Then, when the paper pressing member 111 is raised to the standby position, the energization to the solenoid 156 is stopped, the reverse movement preventing unit 150 is in the first mode state, and a series of cutting operations is completed.

  As described above, during the cutting operation of the sheet cutting apparatus 100, the sheet pressing member 111 stays at a position where the sheet bundle SS is pressed with a predetermined pressing force by the action of the reverse movement preventing unit 150 and continues to be pressed. Therefore, the sheet bundle SS is not shifted during cutting, and the cut edge is not disturbed.

  Further, since the back movement prevention unit 150 is in the first mode state in which power is not supplied to the solenoid 156 during cutting, energy supply for the paper pressing member 111 to press the paper with a predetermined pressing force during cutting is not performed. It becomes unnecessary.

  The reverse movement prevention unit 150 is disposed at a position where rotation of the second pulley 123 is prevented in the pressing movement unit 120 that transmits the driving force of the pressing drive motor M <b> 1 to the sheet pressing member 111. As described above, the pressing movement unit 120 decelerates the rotation of the pressing drive motor M <b> 1 and transmits it to the sheet pressing member 111. Therefore, when the paper pressing member 111 is reversely moved, the movement of the paper pressing member 111 is converted into the increased rotation of the second pulley 123, so that the second pulley 123 is prevented from being reversely moved. It does not require a great force to prevent the rotation. Therefore, when the reverse movement of the paper pressing member 111 is performed by preventing the second pulley 123 from rotating, the ratchet wheel 157 and the ratchet pawl 152 that engages with the ratchet wheel 157 and the support shaft 154 that supports the ratchet pawl 152 are supported. Since a large force is not applied to, the degree of freedom in determining the material and dimensions of these parts can be increased.

  Further, since a trapezoidal screw is used for the screw pressing portion, the conversion efficiency for converting the amount of force that reversely moves the paper pressing member 111 into the amount of force that rotates the rotation shafts 129sA and 129sB is low. Accordingly, when blocking the rotation of the second pulley 123 rotated by the rotation of the rotation shafts 129sA and 129sB, the ratchet wheel 157 and the ratchet pawl 152 that engages with the ratchet wheel 157 and the support shaft 154 that supports the ratchet pawl 152 are provided. Since a large force is not applied, the degree of freedom in determining the material and dimensions of these parts can be further increased.

  As described above, in the post-processing apparatus B in the present embodiment, the sheet pressing member 111 is not moved backward during the cutting of the sheet bundle SS, so that the cut edge is not disturbed, and the sheet pressing member 111 is not cut during the cutting. It is not necessary to supply energy for pressing the sheet bundle SS.

A image forming apparatus 1 image reading unit 2 image processing unit 3 image writing unit 4 image forming unit 5 cassette 6A paper feeding unit 6B paper feeding unit 7 fixing device 8 paper ejection unit 9 operation unit 10A main control unit B post-processing device 10B Post-processing control means 30 Middle folding means 40 Conveying means 50 Signature guide means 60 Saddle binding means 70 Booklet taking out means 80 Booklet conveying means 100 Paper cutting device 110 Pressing part 111 Paper pressing member 111sA, 111sB Protruding part 120 Pressing moving part 121 Belt Deceleration mechanism M1 Press drive motor 122 First pulley 123 Second pulley 124A, 124B Third pulley 125 First drive belt 126A, 126B Second drive belt 127A, 127B Small gear 128A, 128B Large gear 129 Screw pressing portion 129sA, 129sB Rotating shaft 130 Cutting part 131 Cutting blade 137 Mounting table M2 Cutting blade drive motor 140 Reverse motion prevention portion 142 Brake lever 143 Brake pad 144 Support shaft 146 Solenoid 150 Reverse motion prevention portion 152 Ratchet claw 154 Support shaft 156 Solenoid 157 Ratchet wheel S Paper SS Paper bundle

Claims (7)

A paper placement section for placing paper;
A paper pressing portion disposed so as to be close to and away from the paper placement portion;
A pressing movement unit for moving the paper pressing unit;
A cutting unit for cutting the paper placed on the paper placement unit;
Have
The paper pressing unit is moved by the pressing movement unit, and after the paper is placed on the paper placement unit, the paper pressing unit approaches the paper placement unit to press the paper, and the cutting of the paper by the cutting unit is completed. In the post-processing device that is separated from the paper stacking unit,
A post-processing device having a back-motion preventing unit that prevents the sheet pressing unit from moving in a direction away from the sheet placing unit when the sheet pressing unit is in a position for pressing the sheet. . The back motion prevention unit is
A first position that constitutes the pressing movement unit and abuts on any component driven by the movement of the paper pressing unit to stop the movement of the component, and is driven away from the first position. A second braking position that does not interfere with the
The braking unit is moved to the first position from the time when the sheet pressing unit reaches at least a position where the sheet is pressed until the cutting is completed, and the sheet pressing unit is moved to the sheet placing unit. The post-processing apparatus according to claim 1, wherein the post-processing apparatus is moved to the second position when approaching or separating from the sheet placing portion. The pressing and moving part is
A pressing driving force generating section for generating a rotational driving force;
A driving pulley that is rotated by the pressing driving force generation unit; a driven pulley; and a driving belt that is stretched between the driving pulley and the driven pulley, and reduces the rotation of the pressing driving force generation unit. A belt reduction mechanism that transmits the rotational driving force to the driven pulley;
A screw pressing portion comprising: a female screw portion arranged in the paper pressing portion; and a male screw portion provided with a male screw screwed into the female screw portion;
Have
The male screw part is rotated by the driving force of the pressing driving force generating part transmitted through the belt reduction mechanism part, the female screw part is moved in the axial direction of the male screw part, and the paper pressing part is Move in a direction approaching or separating from the paper placement unit,
The post-processing apparatus according to claim 2, wherein the component that abuts when the braking unit is in the first position is the drive belt. The back motion prevention unit is
Constituting the pressing movement part, and a locked part arranged on any part driven by the movement of the paper pressing part;
Engaging with the locked portion, the component is allowed to be driven in a direction in which the paper pressing portion is moved in a direction approaching the paper placement portion, and the component is A first mode that prevents the component from being driven in a direction away from the placement unit; and the component is separated from the locked portion, and the component is separated from the paper placement unit. A second mode that allows it to be driven in a direction to be moved, and a locking portion operable in two modes;
Have
The reverse motion prevention unit operates in the first mode when the paper pressing unit is at least in a position to press the paper placed on the paper placing unit, and the cutting of the paper by the cutting unit is completed. 2. The post-processing apparatus according to claim 1, wherein the post-processing device operates in the second mode when the paper pressing unit is separated from the paper stacking unit. The pressing and moving part is
A pressing driving force generating section for generating a rotational driving force;
A driving pulley that is rotated by the pressing driving force generation unit; a driven pulley; and a driving belt that is stretched between the driving pulley and the driven pulley, and reduces the rotation of the pressing driving force generation unit. A belt reduction mechanism that transmits the rotational driving force to the driven pulley;
A screw pressing portion comprising: a female screw portion arranged in the paper pressing portion; and a male screw portion provided with a male screw screwed into the female screw portion;
Have
The male screw part is rotated by the driving force of the pressing driving force generating part transmitted through the belt reduction mechanism part, the female screw part is moved in the axial direction of the male screw part, and the paper pressing part is Move in a direction approaching or separating from the paper placement unit,
The locked portion is a ratchet wheel disposed on the driven pulley,
When the reverse movement preventing portion operates in the first mode, the locking portion engages with the ratchet wheel while the driven pulley moves the paper pressing portion closer to the paper placement portion. And the driven pulley is prevented from being driven in a direction away from the sheet placing portion, and when operating in the second mode, separated from the ratchet wheel, The post-processing apparatus according to claim 4, wherein the driven pulley is a ratchet pawl that allows the paper pressing portion to be driven in a direction approaching the paper placement portion.   The post-processing apparatus according to claim 3 or 5, wherein the screws arranged in the male screw portion and the female screw portion are trapezoidal screws.   A post-processing device according to claim 1 is connected to an image forming device that forms an image on a sheet, and the post-processing device is interlocked with the operation of the image forming device. An image forming system that performs post-processing on a sheet on which an image is formed by the image forming apparatus.

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