JP6536979B2 - Sheet binding apparatus, sheet processing apparatus, and image forming system - Google Patents

Description

  The present invention relates to a sheet binding device, a sheet processing device, and an image forming system.

  Conventionally, there is known an image forming system provided with a sheet processing apparatus provided with a sheet binding apparatus that performs binding processing on a sheet bundle on which an image is formed by the image forming apparatus using a binding tool as a binding unit. It is done.

  In the sheet processing apparatus described in Patent Document 1, the fibers of the sheets are entangled by strongly engaging the sheet bundle with the pressing teeth, which are the pressing members having a pair of concave and convex shapes, without using metal needles, and the sheets are pressed together. There is provided a sheet binding device of a pressure bonding type, which binds a sheet bundle by causing the sheet bundle to be folded. By binding the sheet bundle by crimping without using a metal needle, it is possible to save time and effort for removing the metal needle from the sheet bundle when discarding the sheet bundle or applying a shredder.

FIG. 24 is a view showing a pair of crimping teeth described in Patent Document 1. As shown in FIG. FIG. 24 is a view as seen from a direction parallel to the sheet surface of the sheet bundle and orthogonal to the arranging direction of the concavities and convexities of the press teeth.
As shown in FIG. 24, the top of the convex portion 172a of the lower pressure bonding tooth 261b is a plane parallel to the sheet surface of the sheet bundle. The concave portion 172b of the lower crimping tooth has a V-shaped groove shape. The convex part 171a of the upper pressure bonding tooth 261a is V-shaped, and the concave part 171b is in the shape of an inverted V-shaped groove.

  As shown in FIG. 24, when the pair of crimp teeth is engaged, the convex portion 171a of the upper crimp tooth 261a contacts the concave portion 172b of the lower crimp tooth 261b, and the concave portion 171b of the upper crimp tooth 261a and the lower crimp tooth 261b. A gap S is generated between the projection 172a and the projection 172a.

  According to this patent document 1, when a pressure is applied from above and below, the load of the fiber of the paper applied to the whole is relaxed by the gap S, and the extension exceeding the limit of the fiber is partially avoided, and the fibers are not broken. It can be intertwined. For this reason, it is described that the whole is not broken and the binding strength is maintained.

  However, in the configuration described in Patent Document 1 described above, the convex portion 171a of the upper pressure bonding tooth 261a is V-shaped, and the top is pointed. Therefore, the pressure is concentrated on the contact portion of the upper crimping teeth 261a with the top of the convex portion 171a of the sheet bundle, and the sheet of the sheet bundle is broken.

  Further, in the configuration described in Patent Document 1, since a gap is formed only between the concave portion 171b of the upper crimping tooth 261a and the convex portion 172a of the lower crimping tooth 261b, the elongation sufficiently exceeds the fiber limit. There was also a problem that the sheets of the sheet bundle were torn apart.

The present invention has been made in view of the above problems, and an object thereof is to provide a sheet binding device, a sheet processing device, and an image forming system capable of suppressing tearing of sheets .

In order to achieve the above object, the invention according to claim 1 is provided with a pair of crimping members having a plurality of convex portions and concave portions on the surface and binding the sheet bundle by sandwiching the sheet bundle, the pair of crimping members Each of the convex portions has an inclined surface, and the inclined surfaces are in contact with each other by sandwiching the sheet bundle by the pair of pressure-bonding members, and the top of the convex portion of one pressure-bonding member and the other pressure-bonding member A gap is formed between the bottom of the recess and the top of the projection of the other crimping member and the bottom of the recess of the one crimping member, with the inclined surfaces in contact with each other. When the pair of pressure-bonding members are viewed in the arranging direction of the convex portion and the concave portion, a shape of a portion where the inclined surfaces are in contact with each other is a hexagon .

According to the present invention, tearing of the sheet can be suppressed.

(A) And (b) is a schematic block diagram which shows an example of the whole structure of the image forming system which concerns on embodiment of this invention, respectively. FIG. 1 is a schematic configuration view showing one configuration example of an image forming apparatus of an image forming system according to the present embodiment. FIG. 1 is a plan view showing a configuration example of a sheet processing apparatus of an image forming system according to the present embodiment. FIG. 2 is a front view of the sheet processing apparatus. FIG. 6 is an explanatory view showing a home position of a fork that branches a sheet received by the sheet processing apparatus. FIG. 8 is an explanatory view showing the position of a fork when the sheet received by the sheet processing apparatus is branched to a branch path. Explanatory drawing which shows an example of the binding tool in the state in which the tooth | gear type was open, and its drive mechanism. Explanatory drawing which shows an example of the binding tool of the state in which the type | mold was closed, and its drive mechanism. (A) And (b) is the top view and front view which respectively show the mode inside the sheet processing apparatus which initialization processing completed. (A) And (b) is the top view and front view which respectively show the mode of the inside of a sheet processing apparatus when receiving a sheet. (A) And (b) is the top view and front view which respectively show the mode inside the sheet processing apparatus when positioning the position of the width direction of a sheet. (A) And (b) is the top view and front view which respectively show the mode inside the sheet processing apparatus when positioning the position of the back end of a sheet. (A) And (b) is the top view and front view which respectively show the mode inside a sheet processing apparatus when receiving the following sheet. (A) And (b) is the top view and front view which respectively show the mode of the inside of a sheet processing apparatus when the following sheet is received. (A) And (b) is the top view and front view which respectively show the mode inside the sheet processing apparatus before the alignment process of a sheet bundle is completed and a binding process is started. (A) And (b) is the top view and front view which respectively show the mode inside the sheet processing apparatus when starting discharge of the sheet bundle which the binding process completed. (A) And (b) is the top view and front view which respectively show the mode inside a sheet processing apparatus when the sheet bundle which the binding process completed is discharged. Explanatory drawing of a crimp binding method. The top view of a lower crimping tooth. The figure seen from the A direction of FIG. FIG. 21 is a view seen from the direction B of FIG. 19; FIG. 7 is a diagram for explaining the behavior of a sheet bundle at the time of pressure bonding; The graph which shows the result of a verification test. The figure shown about a conventional pair of crimp teeth.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIGS. 1A and 1B are each a schematic configuration diagram showing an example of the entire configuration of an image forming system according to an embodiment of the present invention. An image forming system 100 shown in FIG. 1A is a configuration example in which a sheet processing apparatus 201 is incorporated into an image forming apparatus 101 as an image forming unit that forms an image on a sheet as a sheet based on an input image. Further, the image forming system 100 in FIG. 1B is a configuration example in which the sheet processing apparatus 201 is connected to the image forming apparatus 101.

Although the image forming system 100 according to the present embodiment forms an image formed of a toner image on a sheet by electrophotography, it may form an image by another method such as an inkjet method. . Further, in the present embodiment, although an image forming apparatus in which the image forming apparatus 101 and the sheet processing apparatus 201 are combined is described, the present invention is also applied to an image forming apparatus in which the sheet processing apparatus 201 is incorporated in the image forming apparatus 101. it can.
The present invention can also be applied to the case where the sheet processing apparatus 201 is configured to be independent of the image forming apparatus 101. In this case, the sheet processing apparatus may be provided with a cassette or tray in which sheets to be bound are set, a tray in which a sheet bundle is output, or the like.

FIG. 2 is a schematic configuration view showing one configuration example of the image forming system 100 according to the present embodiment.
In FIG. 2, an image forming system 100 is an indirect transfer type tandem color image forming apparatus using an intermediate transfer member. An image forming unit 110 as a toner image forming unit is disposed substantially at the center of the image forming apparatus 101. The image forming unit 110 is an imaging station 111Y, 111M, 111C, 111K (hereinafter referred to as appropriate) of four colors (Y: yellow, M: magenta, C: cyan, K: black) arranged to line up in a predetermined direction. The suffixes Y, M, C, and K are omitted.

The image forming apparatus 101 further includes a sheet feeding tray 120 which is a plurality of sheet feeding units provided below the image forming unit 110 as recording medium supply means. Further, a sheet feeding conveyance path (vertical conveyance path) 130 for conveying a sheet as a recording medium picked up by the sheet feeding tray 120 to the secondary transfer portion 140 and the fixing portion 150 is provided. Further, the image forming apparatus 101 reverses the sheet on which the image is formed on the first surface (front surface), and the branched sheet discharge path 160 for conveying the sheet on which the image (toner image) is fixed to the sheet processing apparatus 201 side. And a duplex conveying path 170 for forming an image on the second surface (rear surface).

  The image forming apparatus 101 further includes a scanner unit 180 as an image reading unit and an automatic document feeder (ADF) 185 as a document supply unit. The scanner unit 180 reads an image of a document as an image reading target set on a glass surface as a document table and converts it into an electric signal. Further, the automatic document feeder (ADF) 185 conveys a plurality of sheets or one sheet of document on which an image is read by the scanner unit 180, and feeds each document onto a glass surface at the reading position of the scanner unit 180. Do.

  The imaging unit 110 includes a photosensitive drum as an image carrier for each color of Y, M, C, and K of the imaging station 111. A charging unit as charging means, a developing unit as developing means, a primary transfer unit, a cleaning unit, and a discharging unit as discharging means are provided around the periphery of each photosensitive drum. ing. The image forming unit 110 also includes an optical writing unit (not shown) as an exposure unit, and an intermediate transfer belt 112 as an intermediate transfer member. The light writing unit is disposed below each image forming station 111, and for each color, light is irradiated to each photosensitive drum based on the image data generated from the reading result of the scanner unit 180, and the electrostatic latent is generated. Form an image. The intermediate transfer belt 112 is disposed above the image forming station 111, and the images (toner images) formed on the respective photosensitive drums are transferred by the primary transfer unit.

  The intermediate transfer belt 112 is rotatably supported by a plurality of support rollers. One of the plurality of support rollers 114 is opposed to the secondary transfer roller 115 via the intermediate transfer belt 112 at the secondary transfer portion 140. At the secondary transfer portion 140, the image (toner image) on the intermediate transfer belt 112 is secondarily transferred to the sheet. A replaceable toner storage container 116 is disposed above the intermediate transfer belt 112.

  The image forming process of the image forming apparatus having the above configuration (the tandem type color image forming apparatus of the indirect transfer system) is well known and is not directly related to the gist of the present invention, and thus the detailed description is omitted.

  The fixed sheet subjected to the fixing process by the fixing unit 150 is conveyed by the conveyance roller 162, and the conveyance direction is switched by the conveyance path switching member 161. As a result, the fixed sheet is conveyed to the branched sheet discharge path 160 or the duplex conveying path 170.

  The sheet processing apparatus 201 according to the present embodiment is provided with a conveyance path binding mechanism as sheet binding means for binding a sheet bundle as a sheet bundle comprising a plurality of sheets as a post-processing of a plurality of sheets including sheets on which an image is formed. ing. The transport path binding mechanism has a configuration for aligning and aligning sheets in the sheet transport path, and a binding tool as binding means for binding the overlaid sheets.

3 and 4 are a plan view and a front view showing a configuration example of the sheet processing apparatus 201 having the conveyance path binding mechanism provided in the image forming system 100 of the present embodiment.
The sheet processing apparatus 201 includes an inlet sensor 202, an inlet roller 203, a branch claw (switching claw) 204, a sheet discharge roller 205, a shift link 206, a shift cam 207, a shift cam stud 208, a shift home position sensor 209, and a binding member 210. .

The entrance sensor 202 detects the front end and the rear end of the sheet carried into the sheet processing apparatus 201 from the sheet discharge roller 102 of the image forming apparatus 101 and the presence / absence of the sheet.
The entrance roller 203 is located at the entrance of the sheet processing apparatus 201 and has a function of carrying a sheet into the sheet processing apparatus 201. By using the roller nip of the inlet roller 203, it is also possible to perform skew correction of the sheet. The inlet roller 203 is driven by a controllable drive source (not shown). The drive source is controlled by control means (not shown), whereby the rotational drive and stop of the inlet roller 203 by the drive source and the transport amount of the sheet by the inlet roller 203 are controlled. The control unit may be provided in the image forming apparatus 101.

  The bifurcated claw 204 is a rotatable claw that switches the conveyance path provided to guide the rear end of the sheet to the branched path 241. Further, the branch claw 204 is configured to be able to press the sheet on the branch path conveyance surface, and the sheet can be fixed by this press.

  A sheet discharge roller 205 is located at the exit of the sheet processing apparatus 201, and has a function of transporting, shifting, and discharging a sheet. Further, the discharge roller 205 is driven by a controllable drive source (not shown). The drive source is controlled by a control unit described later, whereby the rotational drive and stop of the discharge roller 205 by the drive source and the conveyance amount of the sheet by the discharge roller 205 are controlled.

  Conveying means for conveying the sheet in the sheet processing apparatus 201 of the present embodiment includes, for example, an entrance roller 203, a sheet discharge roller 205, and a drive source for driving them.

The shift link 206 is provided at the shaft end of the sheet discharge roller 205, and is a part that receives the shift movement force.
The shift cam 207 has a shift cam stud 208 and is a disk-shaped part that rotates. The rotation of this part shifts the discharge roller 205 connected to the elongated hole of the shift link 206 through the shift cam stud 208.
The shift cam stud 208 interlocks with the elongated hole portion of the shift link 206, and converts the rotational movement of the shift cam 207 into an axial linear movement of the discharge roller 205.

  The shift home position sensor 209 detects the position of the shift link 206, and sets the detected position as a home position (standby position).

  The binding tool 210 is a tool or a device for binding a sheet bundle by squeeze bonding without using a metal needle. In the present embodiment, a binding tool 210 is used in which the sheet bundle is pinched and held by a pair of tooth molds including an upper tooth mold and a lower tooth mold having irregularities on the surface, thereby deforming the paper sheet and entangling fibers. As this type of binding tool 210, for example, a known binding tool as disclosed in Japanese Utility Model Publication No. 36-013206 can be used. Further, the sheet bundle is subjected to U-shaped cutting and bending, a slit is simultaneously opened in the vicinity of the bending source, and the cut and bent tip portion is passed through the slit so as not to be disintegrated, so that the sheet is not used. A binding tool for binding a bundle may be used (see, for example, Japanese Utility Model Publication No. 37-007208). Note that the binding means for binding the sheet bundle is not limited to the binding tool of the present embodiment, as long as it has a function of binding by narrowing crimping processing in which the sheets are crimped to entangle and bind fibers of the sheets. Good.

  A sheet edge sensor 220 as sheet edge detection means is a sensor that detects the side edge of the sheet. When the sheets are aligned, the sheets are aligned based on the detection position detected by this sensor.

  The binding tool home position sensor 221 is a sensor that detects the position of the binding tool 210 that can move in the width direction that intersects the sheet conveyance direction. A position at which the binding tool 210 is located at a position that does not get in the way even when the sheet of maximum size is conveyed is taken as a home position (standby position), and this position is detected by the binding tool home position sensor 221.

  The binding tool moving guide rail 230 is a rail that guides the movement of the binding tool 210 so that the binding tool 210 can stably move in the width direction of the sheet.

  The transport path 240 is a normal path for transporting and discharging the received sheet. The branch path 241 is provided to overlap and align the sheets, and is a transport path that is carried in from the rear end side by switchback of the sheets.

  The abutting surface 242 is a reference surface for abutting and aligning the rear end of the sheet in a binding processing tray (stapler tray) 243 as a sheet storage unit in which sheets to be bound are stored. The pressing tooth 261 is, for example, a tooth type having a shape in which a pair of concavities and convexities are engaged in the present embodiment, and by pinching the sheet, the sheet is deformed and the fibers are entangled.

  FIG. 5 and FIG. 6 are explanatory diagrams showing a detailed configuration example of the bifurcating claw 204 for branching the sheet received by the sheet processing apparatus 201 and the periphery thereof. FIG. 5 is an explanatory view showing the home position of the branch claw 204. As shown in FIG. FIG. 6 is an explanatory view showing the position of the branch claw when the sheet received by the sheet processing apparatus 201 is branched to the branch path 241.

  The branch claw 204 is configured to be rotatable to switch between the transport path 240 and the branch path 241. As shown in FIG. 5, the rotation position at which the sheet received from the right side in the drawing can be transported without resistance is the home position of the bifurcated claw 204. The branch claw 204 is constantly pressurized by a spring 251 as shown in FIG. The spring 251 is hooked on the bifurcated claw movable lever portion 204a. A branch solenoid 250 is also connected to the branch claw movable lever portion 204a via a link. Further, the transport surface of the branch path 241 and the branch claw 204 are configured to be able to sandwich the sheet in the transport path. To switch the conveyance path, turning on the branch solenoid 250 turns the branch claw 204 in the direction of arrow A1 in FIG. 6 to close the conveyance path 240 and guide the sheet to the branch path 241.

  In the present embodiment, the means for overlapping a plurality of sheets to be bound into a sheet bundle includes the entrance roller 203, the sheet discharge roller 205, the bifurcating claw 204, the binding processing tray 243 having the abutment surface 242, and And a drive source for driving the

  7 and 8 are explanatory views showing an example of the configuration and operation of the binding tool 210. As shown in FIG. FIG. 7 is an explanatory view showing an example of the binding tool 210 in a state in which the crimping teeth 261 are open and its driving mechanism, and FIG. 8 is an example of the binding tool 210 in a state in which the crimping teeth 261 are closed and its driving mechanism. FIG. In addition, the structure of the binding tool 210 is not limited to the structure of FIG.7 and FIG.8.

  In FIG. 7, the pressing teeth 261 have an upper pressing tooth 261 a and a lower pressing tooth 261 b and have a meshing shape. The upper crimping teeth 261 a are assembled to the tip of the movable link member 263. The lower crimping teeth 261b are assembled to the fixed link member 264 so as to face the upper crimping teeth 261a. The movable link member 263 is configured such that the pressing teeth 261 come close to each other by the rotation of the pressing lever 262. The pressure lever 262 is rotated in the direction of arrow A3 in FIG. 8 by the cam 266 which rotates in the direction of arrow A2 in FIG. The cam 266 is rotated by applying a driving force from the drive motor 265, and is controlled to be positioned at the detection position based on the detection information of the cam home position sensor 267. The detection position of the cam home position sensor 267 is the home position (standby position) of the cam 266, and in this position, the pair of crimp teeth 261 are in an open state.

  When binding sheets, it operates as shown in FIG. With the pair of press-fit teeth 261 open, the sheet P is inserted therebetween, and the cam 266 is rotated in the direction of arrow A2 in FIG. 8 by the rotation of the drive motor 265. The displacement of the cam surface causes the pressure lever 262 to pivot in the direction of arrow A3 in the figure. The rotational force is increased via a movable link member 263 utilizing a lever, and is transmitted to the upper crimp teeth 261a at the end. When the cam 266 rotates by a predetermined amount, the upper pressure-applying teeth 261a and the lower pressure-applying teeth 261b mesh with each other to hold the sheet P. The sheet P is deformed and pressurized by this pinching, and the fibers of adjacent sheets are entangled and bound. Thereafter, the drive motor 265 rotates in the reverse direction and stops at the detection position of the cam home position sensor 267. Further, the pressure lever 262 has a spring property so that it is bent when an overload is applied to release the overload.

  In the binding tool 210 configured as shown in FIG. 7 and FIG. 8, the binding force which is the engagement force between the pair of pressure-bonding teeth 261 holding the sheet P so as to deform and press the sheet changes, and the fibers of the sheets are intertwined and the sheet bundle The binding strength when binding is changed. The binding force when the pair of pressing teeth 261 is engaged is changed by the rotational force (torque) when rotating the pressure lever 262 via the cam 266, that is, the torque (moment of force) generated by the drive motor 265 Do. The torque generated by the drive motor 265 changes in accordance with the motor current supplied to the drive motor 265. Therefore, by controlling the motor current supplied to the drive motor 265, the binding force of the binding tool 210 is changed according to the binding mode such as the full binding mode and the temporary binding mode, and the binding strength of the sheet bundle is changed. be able to.

Next, an example of the binding operation of the sheet processing apparatus 201 will be described.
9 to 17 are a plan view and a front view of the sheet processing apparatus 201 when the binding operation of this embodiment is performed. In each of FIG. 9 to FIG. 17, a part (a) is a plan view of the sheet processing apparatus 201, and a part (b) is a front view of the sheet processing apparatus 201.

  First, in FIGS. 9A and 9B, when output of a sheet from the image forming apparatus 101 is started, each unit moves to the home position, and the initialization process (initial process) is completed.

  Next, in FIGS. 10A and 10B, before the sheet P output from the image forming apparatus 101 is carried into the sheet processing apparatus 201, the sheet processing apparatus 201 performs the operation mode information and the sheet P. It receives information, and based on the information, it becomes a waiting for acceptance. In addition, although the operation mode in this embodiment is a straight mode, a shift mode, and a binding mode, it is not limited to this.

  Here, the operation of the sheet processing apparatus 201 in the straight mode and the shift mode will be described.

First, the operation of the sheet processing apparatus 201 in the straight mode will be described.
The sheet processing apparatus 201 that has received the information on the straight mode and the information on the sheet P is in the standby standby state for the straight mode. Specifically, the entrance roller pair 203 and the paper discharge drive roller 205a each start rotation in a predetermined rotation direction so as to convey the received sheet P in a predetermined conveyance direction (left direction in the drawing). . The sheet P is fed to the sheet processing apparatus 201 in such a reception standby state by the rotation of the sheet discharge roller 102 of the image forming apparatus 101. The sheet P sent to the sheet processing apparatus 201 is sequentially conveyed and discharged by a pair of sheet discharge rollers including an inlet roller pair 203, a sheet discharge drive roller 205a, and a sheet discharge driven roller 205b. Then, when the final sheet is discharged, the inlet roller pair 203 and the sheet discharge drive roller 205a are stopped.

Next, the operation of the sheet processing apparatus 201 in the shift mode will be described.
The sheet processing apparatus 201 that has received the information on the shift mode and the information on the sheet P is in the shift waiting state. Specifically, in the same manner as in the straight mode, the entrance roller pair 203 and the paper discharge drive roller 205a each have a predetermined rotation direction so as to convey the received sheet P in a predetermined conveyance direction (left direction in the drawing). It starts to rotate. The sheet P is sent from the image forming apparatus 101 to the sheet processing apparatus 201 in such a reception standby state. The sheet fed into the sheet processing apparatus 201 is conveyed by the inlet roller pair 203 and the sheet discharge roller pair as in the straight mode. Next, when the rear end of the sheet passes through the inlet roller pair 203, the shift cam 207 rotates by a fixed amount, and the sheet discharge drive roller 205a moves in the axial direction. At this time, the sheet P is also moved along with the movement of the discharge driving roller 205a. When the sheet P is discharged, the shift cam 207 rotates to return to the home position, and is ready for the next sheet. The operation of the paper discharge drive roller 205a is repeated until the paper of the same "part" is discharged. When a sheet of the next “part” is carried in, the shift cam 207 rotates in the reverse direction to the previous direction, and the sheet moves to the opposite side and is discharged.

  On the other hand, the sheet processing apparatus 201 that has received the information on the binding mode and the information on the sheet P is in the reception standby state for the binding mode. In the reception standby state of the binding mode, the entrance roller 203 is stopped, and the sheet discharge roller 205 rotates in the direction of arrow A6 in the drawing so as to convey the received sheet P in a predetermined conveyance direction (left direction in the drawing). Start. Further, the binding tool 210 moves to a standby position (home position) retracted by a fixed amount from the widthwise end of the sheet P and stands by.

  Thereafter, when the sheet P is carried into the sheet processing apparatus 201, the leading edge of the sheet P is detected by the entrance sensor 202. The sheet P is conveyed from the detected timing by a predetermined distance (a distance which causes the leading end of the sheet P to abut against the nip of the inlet roller 203 to cause a predetermined amount of bending). After the conveyance, the inlet roller 203 starts to rotate. Thereby, the skew of the sheet P is corrected.

  Next, in FIGS. 11A and 11B, the transport amount of the sheet P is counted based on the detection information of the entrance sensor 202 that detects the rear end of the sheet P, and the positional information of the sheet P is grasped. ing. When the trailing edge of the sheet P passes the nip of the inlet roller 203, the inlet roller 203 stops for the next sheet reception. At the same time, the shift cam 207 rotates in the direction of arrow A7 (clockwise direction) in FIG. 11A, and the sheet discharge roller 205 starts to move in the axial direction with the sheet P. Then, the sheet P is conveyed while being skewed in the direction of arrow A8 in FIG. Thereafter, when the sheet edge sensor 220 installed or installed in the binding tool 210 detects the sheet P, the shift cam 207 stops and then reverses. The reverse rotation of the shift cam 207 is stopped when the sheet end sensor 220 is not detected. The above operation is completed, and the rotation of the sheet discharge roller 205 in the direction of the arrow A9 in FIG.

  Next, in FIGS. 12 (a) and 12 (b), the bifurcated claw 204 rotates in the direction of arrow A10 (clockwise) in FIG. 12 (b), and the conveyance path is switched. Thereafter, the sheet discharge roller 205 is reversely rotated in the direction of arrow A11 (counterclockwise direction) in the drawing, and the sheet P is conveyed to the arrow A12 in the drawing so that the rear end portion of the sheet P is carried into the branch path 241. By this conveyance, the sheet P is abutted against the abutting surface 242 of the binding processing tray 243 and aligned, and the sheet discharge roller 205 is stopped. Here, the sheet discharge roller 205 is set to have a weak conveying force so as to slip when the sheet P strikes.

  Next, in FIGS. 13A and 13B, the bifurcated claw 204 rotates in the direction of arrow A13 (counterclockwise direction) in FIG. 13B, and the trailing end of the sheet P in the bifurcated path 241 is a bifurcated claw. It is strongly pressed by the contact surface 204 and stands by. When the subsequent sheet P 'is output from the image forming apparatus 101, as with the first sheet P, the entrance roller 203 performs the skew correction of the sheet P'. Further, at the same time as the rotation of the entrance roller 203 starts, the paper discharge roller 205 also starts to rotate in the rotation direction for conveying the sheet (direction A6 in the figure).

  Next, in FIGS. 14A and 14B, the above-described operations of FIGS. 11 and 12 are performed on the second and subsequent sheets P ′ ′,. The sheet bundle Ps in the aligned state is stacked in the conveyance path by moving and overlapping.

  Next, in FIGS. 15A and 15B, when the operation of superposing the final sheet on the sheet bundle Ps in the aligned state is completed, the sheet discharge roller 205 moves the sheet bundle Ps by a predetermined amount. b) Rotate and stop in the direction of the arrow A14 (clockwise direction) in the middle. By the operation of the paper discharge roller 205, it is possible to eliminate the bending that occurs when the rear end of the sheet abuts against the abutment surface 242. Thereafter, the bifurcating claw 204 is rotated in the direction of arrow A15 (clockwise) in FIG. 15B to switch the direction of the leading end, and the pressing force applied to the sheet bundle Ps is released.

  Next, in FIGS. 16A and 16B, the sheet discharge roller 205 rotates in the direction of the arrow A16, whereby the position of the crimp tooth 261 of the binder 210 matches the processing position of the sheet (binding position). The sheet bundle Ps is conveyed and stopped by the distance that is set. As a result, the position of the crimp tooth 261 of the binding tool 210 in the sheet conveyance direction is matched with the processing position (stapling position) of the sheet. Further, the binding tool 210 is moved in the direction of arrow A17 in FIG. 16A and stopped by the distance corresponding to the position of the crimp tooth 261 of the binding tool 210 and the processing position of the sheet. Thereby, the position of the crimp tooth 261 of the binding tool 210 in the sheet width direction is matched with the processing position (stapling position) of the sheet. At this time, the bifurcating claw 204 rotates in the direction of arrow A18 (counterclockwise) in FIG. 16B to switch the direction of the leading edge, and returns to the paper receiving state. Thereafter, the drive motor 265 of the binding tool 210 is turned on, and the sheet bundle Ps is pressed and squeezed by the pressing teeth 261, whereby the fibers of the respective sheets P entangle each other and the sheets are coupled to each other. Is bound.

  Next, in FIGS. 17A and 17B, when the sheet discharge roller 205 further rotates in the direction of the arrow A16 in the drawing, the bound sheet bundle Ps is discharged. Then, after the sheet bundle Ps is discharged, the shift cam 207 rotates in the direction of A19 in the drawing to return to the home position, and the binding tool 210 moves in the direction of arrow A20 in the drawing to return to the home position. Thus, the operation of the binding process of the sheet bundle Ps is completed.

FIG. 18 is an explanatory view of a pressure bonding method.
As shown in FIG. 18A, in the binding tool 210, the upper crimping teeth 261a and the lower crimping teeth 261b having the concavo-convex shape are disposed at positions facing each other so as to sandwich the sheet bundle Ps. Then, as shown in FIG. 18B, at least one pressing tooth is moved, the upper pressing tooth 261a and the lower pressing tooth 261b are engaged so as to sandwich the sheet bundle Ps, and pressure is applied to the sheet bundle Ps. As the pressure is increased, the fibers of the paper are entangled, and the binding of the sheet bundle Ps is completed. In this pressure-bonding binding, the sheet bundle Ps can be bound by entanglement and fixation of fibers between the sheets by pressing and squeezing the sheet bundle Ps by fitting of the unevenness.

  Thereafter, as shown in FIG. 18C, at least one crimp tooth is moved again to separate the upper crimp tooth 261a from the lower crimp tooth 261b. As shown in FIG. 18D, the uneven shape is transferred to the sheet bundle Ps that has been crimped and bound.

  In the present embodiment, the concavo-convex shapes of the upper crimping teeth 261 a and the lower crimping teeth 261 b have inclined surfaces at arbitrary angles. Further, when the upper crimping teeth 261a and the lower crimping teeth 261b are engaged, the top of the upper crimping teeth 261a and the bottom of the lower crimping teeth 261b are not in contact with each other. As a result, the sheet bundle Ps is crimped on the inclined surface of the uneven shape of the upper crimping teeth 261a and the lower crimping teeth 261b. As shown in FIG. 18D, the concave portion 6a of the sheet bundle Ps is an expanded portion squeezed by the convex portion of the upper crimping tooth 261a, and the convex portion 6b of the sheet bundle Ps is a convex portion of the lower crimping tooth 261b. It becomes an expanded part squeezed by. Further, the sloped portion 6c of the uneven portion of the sheet bundle Ps is a portion bound by pressure bonding.

  Next, the concavo-convex shape of the pair of crimp teeth, which is a feature of the present embodiment, will be described. The shape of the upper crimping teeth 261 a and the shape of the lower crimping teeth 261 b are the same, so in the following description, only the lower crimping teeth 261 b will be described.

FIG. 19 is a plan view of the lower pressure-bonding teeth 261b, FIG. 20 is a view seen from the A direction of FIG. 19, and FIG. 21 is a view seen from the B direction of FIG. The dotted lines in FIGS. 20 and 21 indicate the upper pressure-bonding teeth 261a, and the dashed-dotted line indicates the sheet bundle Ps.
As shown in FIG. 19, the lower crimping teeth 261 b form a concavo-convex shape by arranging the plurality of convex portions 70 b at predetermined intervals.

  Each convex portion 70b has a shape in which a quadrangular pyramid is cut parallel to the bottom near the center in the height direction, and the top 71b is a surface parallel to the sheet surface of the sheet bundle. Here, "a plane parallel to the paper surface" includes a surface substantially parallel to the paper surface, and as shown in FIG. 20, includes a surface which is slightly mountain-shaped. The four side surfaces having the bottom side of each of the convex portions 70b as the bottom side and the one side of the top surface as the top side are slope portions 72b which are inclined with respect to the sheet surface of the sheet bundle Ps.

  B in FIG. 20 is a crimp height, and shows a contact portion between the sloped portion 72b of the lower crimp tooth 261b and the sloped portion 72a of the upper crimp tooth 261a. The arrow Z in FIG. 20 is a portion where the sheet is stretched by the convex portion 70 b. Further, θ2 in FIG. 21 is a turning side rake angle, and is 60 ° in the present embodiment. In addition, S in FIG. 21 is a crimping area where the sheet is crimped.

FIG. 22 is a diagram for explaining the behavior of the sheet bundle Ps at the time of pressure bonding.
As shown in FIG. 22 (a), when one pressing tooth is moved and the upper pressing tooth 261a and the lower pressing tooth 261b are engaged so as to sandwich the sheet bundle Ps, the sheet is a convex portion of each pressing tooth. It is squeezed and extended by the tops 71a and 71b. In the present embodiment, since the tops 71a and 71b of the convex portions of the respective pressing teeth are parallel to the sheet surface of the sheet bundle Ps, the pressure between the tops 71a and 71b of the convex portions of the respective pressing teeth and the sheet bundle Ps Can be kept low. As a result, it is possible to suppress that the sheet bundle Ps is torn by the top portions 71a and 71b of the convex portions.

  Further, in a process in which the upper crimping teeth 261a and the lower crimping teeth 261b mesh with each other, the sheet bundle Ps is pinched by the inclined surface 72a which is the side of the convex portion 70a of the upper crimping teeth 261a and the inclined surface 72b of the lower crimping teeth 261b. The rolling of the portion (the portion encircled by a circle in FIG. 22A) causes entanglement between the fibers.

  In the present embodiment, the sheets are pressure-bonded by the inclined portions 72a and 72b inclined with respect to the sheet surface of the sheet bundle Ps. The pressing force in the vertical upward direction applied to the sheet bundle Ps from the sloped portion 72b of the lower crimping teeth 261b is divided into a direction perpendicular to the sloped portion 72b and a direction parallel to the sloped portion 72b. The direction of the component force in the direction is the direction toward the top 71 b of the lower crimping tooth 261 b. Similarly, the direction of the component force in the direction parallel to the slope portion 72a of the downward downward pressure applied to the sheet bundle Ps from the slope portion 72a of the upper crimping tooth 261a is the direction toward the top 71a of the upper crimping tooth 261a. . Therefore, at the crimping point of the bundle of sheets Ps surrounded by a circle in the figure, the sheet on the lower crimping tooth side moves upward along the inclined surface 72b, and the sheet on the upper crimping tooth side moves to the lower side along the inclined surface 72a. Move to As a result, the sheet is crushed at the crimped portion of the sheet bundle Ps, fibers of the sheets can be further entangled, and the binding can be performed with a strong binding force.

  As shown in FIG. 22 (b), when the upper pressure-bonding tooth 261a is moved to the bottom dead center, between the top 71b of the projection 70b of the lower pressure-bonding tooth 261b and the bottom 73a of the recess of the upper pressure-bonding tooth 261a, The clearance S is formed between the top 71a of the projection 70a of the upper crimping tooth 261a and the bottom 73b of the recess of the lower crimping tooth 261b. As described above, in the present embodiment, the sheet on the lower crimping tooth side moves upward along the slope portion 72b at the crimping point of the bundle of sheets Ps enclosed by the circle in FIG. 21A, and the upper crimping tooth The sheet on the side moves downward along the slope portion 72a. As described above, since the sheet rubs and moves at the crimped portion, as shown in FIG. 22B, the sheet is bent so as to be corrugated in the gap S between the tops 71a and 71b of the convex portions and the bottoms 73a and 73b of the concaves. . Unlike the present embodiment, when the top of each protrusion contacts the bottom of the recess and the gap S is not formed, the distortion between the top of each protrusion and the bottom of the recess is generated. Eventually, the paper will be crushed, resulting in damage to the paper such as wrinkles. On the other hand, in the present embodiment, when the upper pressure-bonding teeth 261a are moved to the bottom dead center, the gap S is generated between the tops 71a and 71b of the respective projections and the bottoms 73a and 73b of the recesses. It will not be crushed. Conversely, the fibers of the paper can be intertwined in the gap S between the tops 71a and 71b of the protrusions and the bottoms 73a and 73b of the recesses while being appropriately pressed by the throttling by the protrusions 70a and 70b. The sheet bundle can be strongly bound.

  In addition, when pressure is applied to the sheet bundle Ps at the slope portions 72a and 72b, the rubbed sheet can be moved to the gap S. As a result, the sheet can be ground well at the pressure-bonded portion, and a good binding force can be obtained.

  In the present embodiment, the sheet is squeezed by the paper bundle by squeezing the fibers of the paper by rubbing the paper at the pressure-bonded area surrounded by the circle in FIG. Be done. The crimped area S (see FIG. 21) increases as the crimp height B, which is the contact range between the sloped portion 72b of the lower crimping teeth 261b and the sloped portion 72a of the upper crimping teeth 261a shown in FIG. The paper stack can be bound to However, when the crimp height B is long, the length from the top portion 71b of the convex portion of the lower crimp tooth 261b to the top portion 71a of the convex portion of the upper crimp tooth 261a becomes longer when engaged. As a result, the sheet is stretched by that much, and the stretch of the sheet may exceed the limit, and a tear may occur.

  Therefore, the present inventors intensively conducted a verification test to find an optimum crimp height B. Below, the verification test which the present inventors performed is demonstrated.

  In the verification test, a binder with a crimp height B of 0.45 mm, a binder with a crimp height B of 0.6 mm, and a binder with a crimp height B of 0.7 mm are prepared. The binding force was measured. Since it is general to staple five sheets of paper before and after the binding force, a bundle of five sheets is bound with each binding tool, and the binding force of the sheet bundle is measured.

Moreover, the other conditions of each binding are as follows.
Pressure force: 2000 N
· Number of teeth: 6 teeth (number of projections)
· Turning side rake angle θ2: 60 °

  FIG. 23 is a graph showing the results of the verification test. FIG. 23 shows the results of verification tests of the binding force of the first sheet (uppermost sheet) of the sheet bundle and the binding force of the sheet at the center of the sheet bundle (the third sheet from the top). Moreover, FIG. 23 plots the binding force of the minimum value among the plurality of times of performing the binding force measurement.

  As shown in FIG. 23, by setting the crimp height B to 0.45 mm or more, the binding force can be made to the target level or more. In addition, when the crimp height B is 0.6 mm, the binding force peaks, and the binding tool with the crimp height B 0.7 mm has a reduced binding force compared to the binding tool with the crimp height B 0.6 mm. . Since the binding force is reduced when the sheet is broken, the sheet is bound with a binding tool having a binding height B of 0.7 mm, which is lower than 0.6 mm in spite of the increase in the binding height B. Is considered to be broken

  From the above verification test, it was confirmed that, by setting at least the pressing height B to at least 0.45 mm and at most 0.6 mm, a good binding force can be obtained without tearing the sheet.

  In addition, even when the crimp height is 0.45 mm or less, it is possible to make the binding force equal to or higher than the target level by increasing the number of teeth (the number of projections) or by increasing the pressing force. is there. However, increasing the number of teeth increases the size of the binding tool, increases the material cost, and increases the cost of the apparatus. In addition, it consumes a lot of material and wastes resources. In addition, in order to increase the pressing force, it is necessary to increase the driving force of the driving source necessary for pressing, which causes a disadvantage that the power consumption of the device increases. On the other hand, by setting the crimp height to 0.45 mm or more, the number of teeth can be suppressed, the material cost can be suppressed, and the cost increase of the device can be suppressed. In addition, resource saving can be achieved. Further, the pressing force can be suppressed, and energy saving can be achieved.

What has been described above is an example, and the present invention exhibits unique effects in each of the following modes.
(Aspect 1)
A binding method using a crimping binding method in which a bundle of sheets is stapled by interposing the concavities and convexities of a pair of crimping members such as a pair of crimping teeth in which a plurality of concave portions and a plurality of convex portions are alternately arranged in parallel In the sheet binding apparatus such as the tool 210, in each of the pair of pressure-bonding members, the tops 71a and 71b of the convex portions are surfaces parallel to the sheet surface of the sheet bundle, and the side surfaces of the convex portions The inclined surfaces 72a and 72b are inclined surfaces, and when the projections and recesses of the pair of crimping members are engaged with each other, the inclined surfaces come into contact with each other, and the tops 71a of the convex portions of one of the crimping members A pair of crimping members is formed such that a gap S is formed between the bottom 73b of the recess of the other crimping member and between the top 71b of the projection of the other crimping member and the bottom 73a of the recess of one crimping member. Configured.
According to (Aspect 1), when the pair of crimping members are engaged, the inclined surfaces which are the side surfaces of the convex portions of the pair of crimping members are in contact with each other. It receives pressure on inclined surfaces and is bound. At this time, between the top of the projection of one crimping member and the bottom of the recess of the other crimping member, or between the top of the projection of the other crimping member and the bottom of the recess of one crimping member There are also gaps. Therefore, compared to the configuration described in Patent Document 1 in which there is only a gap between the top of the projection of one crimping member and the bottom of the recess of the other crimping member, the paper fiber load is further reduced. it can. Thereby, the extension beyond the limit of the fibers can be avoided as compared with Patent Document 1, and compared with Patent Document 1, the fibers can be entangled without being broken.
Further, since the crests of the convex portions of both the pressure-bonding members are parallel to the sheet surface of the sheet bundle, the portions contacting the crests of the convex portions of one pressure-bonding tooth of the sheet bundle and the sheet bundle The contact with any of the projections of the other pressing tooth and the pressure contact is prevented. Thus, it is possible to suppress the sheet bundle from being broken at the time of the pressure bonding.

(Aspect 2)
In (Aspect 1), when a pair of crimping members is viewed from the direction parallel to the sheet and the direction orthogonal to the arranging direction of the concave and convex portions, the length of the portion where the inclined surfaces contact with each other A sheet binding device characterized in that the (crimping height B) is set to not less than 0.45 mm and not more than 0.6 mm.
According to (Aspect 2), as described in the verification test, by setting the length (crimp height B) of the portion where the inclined surfaces contact each other to 0.45 mm or more and 0.6 mm or less, It is possible to suppress tearing and obtain good binding strength.

(Aspect 3)
In a sheet processing apparatus 201 including at least a sheet binding apparatus such as a binding tool 210 that performs binding processing on a sheet bundle Ps, the sheet binding apparatus according to (Aspect 1) or (Aspect 2) is used as a sheet binding apparatus. It was.
According to (Aspect 3), as described in the embodiment, the tearing of the sheet can be suppressed, and a good binding force can be obtained.

(Aspect 4)
In an image forming system 100 including an image forming apparatus 101 for forming an image on a sheet of paper and a sheet binding apparatus such as a binding tool 210 for performing binding processing on a bundle of sheets on which the image is formed by the image forming apparatus 101 As the sheet binding device, the sheet binding device of (Aspect 1) or (Aspect 2) was used.
According to (Aspect 4), it is possible to suppress the tearing of the sheet and to bind the sheet bundle on which the image is formed with a good binding force.

70a, 70b: convex portions 71a, 71b: top portions 72a, 72b: slope portions 73a, 73b: bottom portion 100: image forming system 101: image forming apparatus 201: sheet processing device 210: binding tool 261: crimping teeth 261a: upper crimping teeth 261b: lower crimp teeth Ps: sheet bundle

WO2009 / 110298

Claims (8)

A pair of pressure-bonding members having a plurality of convex portions and concave portions on the surface and binding the sheet bundle by sandwiching the sheet bundle,
The convex portion of each of the pair of crimping members has an inclined surface,
By sandwiching the sheet bundle with the pair of crimping members, the inclined surfaces are in contact with each other, and between the top of the convex portion of one crimping member and the bottom of the recess of the other crimping member and the other crimping member A gap is formed between the top of the projection and the bottom of the recess of one of the crimping members,
When the pair of crimp members are viewed from the direction in which the convex portion and the concave portion are arranged in a state in which the inclined surfaces are in contact with each other, a shape of a portion where the inclined surfaces are in contact is a hexagon. Paper binding device to be.   In the sheet binding device according to claim 1,
The shape of the portion where the inclined surfaces are in contact is the intersection point of the inclined surfaces of the convex portions of the pair of crimping members when the pair of crimping members are viewed from the arranging direction of the convex portions and the concave portions. A sheet binding device characterized by being symmetrical about a line. In the paper binding device according to claim 1 or 2,
The inclined surfaces of the convex portions of the pair of crimping members have a planar shape,
A sheet binding device characterized in that a sheet bundle is held between the planar shapes of the inclined surfaces . The sheet binding device according to any one of claims 1 to 3.
The top of the convex part of the pair of pressure-bonding members has a curved surface shape. The sheet binding device according to any one of claims 1 to 4.
A sheet binding apparatus, wherein the pair of pressure-bonding members crimps a sheet bundle at a portion where the inclined surfaces are in contact with each other. The sheet binding device according to any one of claims 1 to 5 .
A conveying member for conveying the sheet bundle;
A sheet binding apparatus, comprising: the pair of pressure-bonding members sandwiching a sheet bundle in a state in which the conveyance of the sheet bundle by the conveying member is stopped; A sheet processing apparatus comprising at least a sheet binding device for performing a binding process on a sheet bundle,
A sheet processing apparatus using the sheet binding device according to any one of claims 1 to 6 as the sheet binding device. An image forming apparatus for forming an image on a sheet;
An image forming system including: a sheet binding device that performs a binding process on a bundle of sheets on which an image is formed by the image forming apparatus;
An image forming system using the sheet binding device according to any one of claims 1 to 6 as the sheet binding device.

Images