JP2014172684A - Paper post-processing device and image forming system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a paper post-processing device capable of center binding processing and center folding processing, without damaging paper, when the center binding processing paper number is many or even when a paper thickness is thick, by executing center binding processing without using a metallic needle.SOLUTION: Among a pair of paper 5 positioned in both end parts in the overlapping direction of a paper bundle 6, one paper 5 is processed so as to have an engaging piece 5d. The engaging piece 5d is not provided in the other paper 5 for constituting the paper bundle 6. As a first stage of a folding process, the engaging piece 5d is folded and inserted into a first hole 5a of the other paper 5. Next, the engaging piece 5d is folded along an upper surface of the paper bundle 6, and then, is inserted into a second hole 5b. The tip part side of the engaging piece 5d is run along an under surface of the paper bundle 6, and thereby, the paper bundle 6 is bound by the engaging piece 5d.

Description

  The present invention relates to a sheet post-processing apparatus and an image forming system that combines this with an image forming apparatus.

  As a paper post-processing device that is attached to the image forming apparatus and constitutes the image forming system, a function for stapling the paper ejected from the image forming apparatus as a bundle and a booklet processing for folding the stapled paper bundle into two What has a function is known.

  In the conventional paper post-processing apparatus, metal needles are used as staples used for stapling. However, in the current environment-oriented society, the consumption of energy and resources for manufacturing metal needles is a problem. Another problem is that the metal needles must be removed for sorting and collection at the time of disposal of documents, and cumbersome processing must be performed at the time of disposal. Furthermore, when separating a document bound with a staple, for example, for copying, it is necessary to bind again with a new needle after removing the needle, which wastes energy and resources.

  Patent Document 1 discloses a technique for solving problems such as separation when discarding a bundle of recording materials by using a metal needle or the like. This technology is a binding mechanism that presses (presses) teeth (crimped teeth) composed of bar code-like irregularities so as to mesh with each other from the vertical direction (thickness direction) on the folded paper. Have Then, the folded sheet is locally deformed, and the sheet bundle is bound by the meshing of the sheets at the deformed portion (binding portion, crimp binding portion). In addition, a slit-like cut corresponding to the width of the U-shaped blade is formed in the sheet bundle by the cutter mechanism. A U-shaped cut is formed in the sheet bundle by the U-shaped blade and the U-shaped hole. Next, the U-shaped cut is pushed into the slit-shaped cut at one end of the push cam, and the sheet bundle is deformed in the thickness direction to bind the sheet bundle.

  However, the above-described prior art has a problem when performing the middle folding process in the saddle stitching process. That is, when the number of paper bundles is large or the paper thickness is thick, the paper outside the paper bundle is pulled when the paper bundle is folded. Then, there is a problem that the slit-shaped cutting position is slipped and the pressure bonding is peeled off, or the U-shape is deformed and the saddle stitching process is peeled off. There is also a problem that the paper is torn.

  SUMMARY An advantage of some aspects of the invention is to provide a sheet post-processing apparatus capable of performing saddle stitching without using a metal needle, and an image forming apparatus including the sheet post-processing apparatus.

  The paper post-processing apparatus according to the present invention can provide a first hole in the paper, a second hole in the paper, and an engagement piece in the paper by cutting the paper. A processing unit and a control unit that controls the processing unit to provide the first hole and the second hole in each of a plurality of sheets, and to provide the engaging piece on one or more of the plurality of sheets. And passing through the first hole a bundling unit that stacks the plurality of sheets to form a sheet bundle, and an engagement part including one or two or more of the engagement pieces stacked on each other in the sheet bundle, Passing the engaging portion passed through the first hole through the second hole to bind the sheet bundle, and folding the sheet bundle subjected to saddle stitching at the sheet binding portion. And the control unit is configured so that the holes of the sheets are aligned when the sheet bundle is folded. Hole, and performing control to enable drilling by shifting the position of the second hole in each sheet.

  According to the present invention, the saddle stitching process can be performed without using a metal needle, and even when the number of sheets to be saddle stitched is large or the sheet thickness is thick, the saddle stitching process and the middle folding process can be performed without damage to the sheet. .

1 is a side sectional view showing a schematic configuration of an image forming system of the present invention. Block diagram showing the electrical connection of each part of the paper post-processing device The top view which shows the 2nd paper by edge binding The top view (A) which shows the 1st paper by edge binding, and the perspective view (B) which shows the 1st paper by edge binding A plan view showing a second sheet with saddle stitching (A) and a plan view showing a first sheet with saddle stitching (B) The flowchart which shows the flow of the edge binding process which a paper post-processing apparatus performs An exploded perspective view showing a sheet bundle The cross-sectional view (A) showing the sheet bundle and the binding member in the first stage of the folding process in the binding process is the cross-sectional view (B) showing the paper bundle and the binding member in the second stage of the folding process in the binding process. Sectional view (C) showing the sheet bundle and binding member in the second hole passing step in the processing, sectional view (D) showing the sheet bundle and binding member in the first stage of the pressing step in the binding processing, in the binding processing Sectional view (E) showing the sheet bundle and the binding member in the second stage of the pressing process A bottom view (A) showing the sheet bundle in the end-bound state, and a plan view (B) showing the sheet bundle in the end-bound state. Sectional drawing which follows the A1-A1 line of FIG.9 (B) A plan view showing a sheet bundle and a binding member during the binding process Exploded perspective view showing a stack of sheets with the punching position shifted Principle of paper thickness detection means

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
In the sheet post-processing apparatus according to the embodiment of the present invention, a cut (half-cut) and a first hole are provided in at least one sheet bundle (this sheet is referred to as A). Other sheets are provided with a first hole and a second hole (this sheet is referred to as B). Then, the portion surrounded by the cuts of the paper A (the section) is bent and sequentially passed through the second holes of the plurality of papers B, and the cuts are bound through the first holes of all the papers. The first hole and the second hole are shifted for each sheet by the processing and the folding processing function for folding the bound sheet bundle. As a result, the holes of the respective sheets are aligned after the folding process is performed.

The above features will be described with reference to the following drawings.
FIG. 1 is a side sectional view showing a schematic configuration of an image forming system of the present invention. As shown in FIG. 1, the image forming system 1 of this embodiment includes an image forming apparatus 2 and a sheet post-processing apparatus 3. The image forming apparatus 2 and the sheet post-processing apparatus 3 are connected so as to communicate with each other. In this image forming system 1, the image forming apparatus 2 forms an image on a sheet 5 (see FIG. 3), the sheet post-processing apparatus 3 receives the sheet 5 from the image forming apparatus 2, and performs various post-processing on the received sheet 5. Apply processing. The various post-processing includes, for example, end binding processing, center folding processing, and the like. The half-folding process includes a saddle stitching process. In the present embodiment, in the edge binding process and the saddle stitching process, the sheet post-processing device 3 uses the sheet bundle 6 (see FIG. 7) as a part of the sheet bundle 6 (sheet 5) without using a needle. Bind. The sheet post-processing apparatus 3 that performs such various post-processing has a discharge mode, an end binding mode, and a middle folding mode as operation modes.

  The image forming apparatus 2 has a known configuration. For example, the image forming apparatus 2 can be configured as an electrophotographic color image forming apparatus. The image forming apparatus 2 includes, for example, a control unit, an image forming unit, an optical writing unit, a paper feed unit, a paper feed conveyance path, an image reading unit, an intermediate transfer unit, a fixing unit, a paper discharge conveyance path, a double-side conveyance path, and the like ( Neither is shown), and an image is formed on both sides or one side of the paper 5.

  The sheet post-processing apparatus 3 includes a first transport path Pt1 for receiving the sheet 5 discharged from the image forming apparatus 2 and discharging it to the first sheet discharge tray 10. Further, a second transport path Pt2 is provided for branching from the first transport path Pt1 and for performing an end binding process or the like on the sheet bundle 6. Further, a third transport path Pt3 is provided which is connected to the second transport path Pt2 and performs the saddle stitching and folding process on the sheet bundle 6. Each of the transport paths Pt1 to Pt3 is formed by, for example, a guide member (not shown).

  In the first transport path Pt1, an entrance roller 11, transport rollers 12, 13, and a paper discharge roller 14 are arranged in order from the upstream portion to the downstream portion of the first transport path Pt1. The entrance roller 11, the transport rollers 12 and 13, and the paper discharge roller 14 are rotationally driven by a motor to transport the paper 5. An inlet sensor 15 is disposed upstream of the inlet roller 11. The entrance sensor 15 detects that the sheet 5 has been carried into the sheet post-processing device 3. A processing portion 16 that forms a hole or the like in the paper 5 is disposed downstream of the entrance roller 11. The process part 16 is a press apparatus which performs a punching process as an example. The processing section 16 has a punch section 16a and a die section 16b, and punches the paper 5 by the punch section 16a. Further, a branching claw 17 is disposed downstream of the conveying roller 12. The branch claw 17 rotates and switches its position, thereby selecting the paper 5 to be either the downstream portion of the branch claw 17 in the first transport path Pt1 or the second transport path Pt2. To guide you. The branch claw 17 is driven by, for example, a motor or a solenoid.

  In the discharge mode, the paper 5 carried into the first transport path Pt1 from the image forming apparatus 2 is transported by the entrance roller 11, the transport rollers 12, 13 and the paper discharge roller 14, and is transferred to the first paper discharge tray 10. Discharged. On the other hand, in the end binding mode and the middle folding mode, the paper 5 carried into the first transport path Pt1 is transported by the entrance roller 11 and the transport roller 12, and the traveling direction is changed by the branching claw 17, so that the first 2 is conveyed to the second conveyance path Pt2.

  In the second transport path Pt2, transport rollers 20 to 22, a paper stacking tray 23, a first jogger fence 24, and an end binding unit 25 are arranged. The end binding unit 25 is an example of a sheet binding unit. The transport rollers 20, 21 and 22 are driven by a motor to transport the paper 5. The first jogger fence 24 is driven by a motor. In addition, branch claws 26 and 27 are arranged downstream of the paper stacking tray 23. The branch claws 26 and 27 are rotated to switch their positions, so that the sheet 5 is transferred to either the downstream portion of the branch claw 17 in the first transport path Pt1 or the third transport path Pt3. Selectively guide to. The branch claws 26 and 27 are driven by, for example, a motor or a solenoid.

  In the edge binding mode, the sheets 5 conveyed to the second conveyance path Pt2 are sequentially accumulated on the sheet accumulation tray 23 by the conveyance rollers 20, 21, and 22. Thereby, a sheet bundle 6 in which a plurality of sheets 5 are laminated is formed. At this time, the sheet 5 comes into contact with a first movable reference fence (not shown) provided on the sheet stacking tray 23 at the rear end thereof, and the sheet conveyance direction position is aligned. Further, the paper 5 is aligned in the width direction by the first jogger fence 24. The first movable reference fence is driven by a motor. Here, the paper stacking tray 23, the first jogger fence 24, and the first movable reference fence constitute a first bundling unit 28 as a bundling unit that stacks a plurality of papers 5 to form a paper bundle 6. ing. The first bundling unit 28 includes a motor that drives the first jogger fence 24 and a motor that drives the first movable reference fence. Then, the sheet bundle 6 is conveyed to the end binding portion 25 by the first movable reference fence, and the end portion is bound by the end binding portion 25. The sheet bundle 6 with the edge bound is conveyed to the first conveyance path Pt1 by the first movable reference fence, and then conveyed by the conveyance roller 13 and the discharge roller 14 to the first discharge tray 10. Discharged. Here, the paper discharge roller 14 is an example of a paper discharge unit that discharges the sheet bundle 6 bound by the end binding unit 25.

  On the other hand, in the middle folding mode, the sheet 5 conveyed to the second conveyance path Pt2 is conveyed to the third conveyance path Pt3 by the conveyance rollers 20, 21, 22 and the first movable reference fence. Conveying rollers 31 and 32 and a saddle stitch folding part 33 are arranged in the third conveying path Pt3. The transport rollers 31 and 32 are driven by a motor to transport the paper 5. The saddle stitch folding part 33 includes a center folding part 34, a saddle stitching part 35, and a second bundling part 36. The saddle stitching portion 35 is an example of a sheet binding portion. The sheets 5 conveyed to the third conveyance path Pt3 are sequentially accumulated in the second bundling unit 36 by the conveyance rollers 31 and 32. Thereby, a sheet bundle 6 in which a plurality of sheets 5 are laminated is formed. At this time, the front end of the paper 5 abuts against the second movable reference fence 37, the paper transport direction position is aligned, and the width direction position is aligned by a second jogger fence (not shown). The sheet bundle 6 is bound (saddle-stitched) by the saddle stitching section 35 at the center in the sheet transport direction. The saddle-stitched sheet bundle 6 is returned to the center folding position by the second movable reference fence 37. The second movable reference fence 37 is driven by a motor.

  The sheet bundle 6 positioned at the center folding position is folded (center folded) by the center folding section 34 at the center in the sheet transport direction. In the middle folding portion 34, the blade 38 facing the central portion in the paper conveyance direction of the paper bundle 6 located at the middle folding position moves from the right to the left in FIG. 1 to bend the central portion in the paper conveyance direction of the paper bundle 6. While pushing, it pushes between a pair of press rollers 39,40. The blade 38 is driven by a motor. The folded sheet bundle 6 is pressed from above and below by the pair of pressing rollers 39 and 40. The pair of pressing rollers 39 and 40 are driven by a motor. The sheet bundle 6 bent in this way is discharged onto the second discharge tray 42 by the pressing rollers 39 and 40 and the discharge roller 41. The paper discharge roller 41 is driven by a motor. Here, the paper discharge roller 41 is an example of a paper discharge unit that discharges the sheet bundle 6 bound by the saddle stitching unit (paper binding unit) 35.

  Here, the entrance roller 11, the transport rollers 12, 13, 20 to 22, 31 and 32 and the paper discharge rollers 14 and 41 constitute a transport unit 51 together with a motor for driving them. Further, the branch claws 17, 26 and 27 constitute a path switching unit 52 together with a motor or a solenoid for driving them.

  FIG. 2 is a block diagram showing the electrical connection of each part of the sheet post-processing apparatus. As shown in the figure, the sheet post-processing apparatus 3 includes a control unit 61. The control unit 61 is a computer having a CPU, a storage unit, a communication interface, and the like. The storage unit of the control unit 61 is configured by a ROM, a RAM, and the like, and stores a program executed by the CPU. The control unit 61 is connected to the inlet sensor 15, the processing unit 16, the first bundling unit 28, the saddle stitch folding unit 33, the transport unit 51, the path switching unit 52, and the like. The control unit 61 (CPU) drives and controls each unit of the sheet post-processing apparatus 3 according to a program stored in the storage unit. The control unit 61 is connected to the control unit of the image forming apparatus 2 so that data communication is possible.

  Next, end binding processing that is an example of binding processing will be described in detail. 3 is a plan view showing a second sheet with end binding, FIG. 4A is a plan view showing a first sheet with end binding, and FIG. 4B is a first sheet with end binding. It is a perspective view shown.

  As shown in FIG. 3, the processing unit 16 that processes the paper 5 in the end binding process can provide the first hole 5 a in the paper 5 and provide the second hole 5 b in the paper 5. It is. Specifically, the punch portion 16a has a punch for punching and forming the first hole 5a and a punch for punching and forming the second hole 5b. The first hole 5a and the second hole 5b are formed by these punches. The first hole 5a and the second hole 5b are provided at one corner of the rectangular paper 5 as an example. The second hole 5b is provided between the first hole 5a and the outer edge of the paper 5, and is separated from one edge of the first hole 5a by a predetermined distance. The second hole 5b is a smaller hole than the first hole 5a. The second hole 5b is formed in a slit shape. In other words, the first hole 5a and the second hole 5b are, for example, an insertion hole and a locking hole. For example, the processing unit 16 processes the sheets 5 one by one (in units of one sheet).

  As shown in FIG. 4A, the processing unit 16 can provide the engagement piece 5 d having a U-shaped outer shape on the paper 5 by making a cut 5 c (half cut) in the paper 5. Specifically, the punch portion 16a has a punch for punching and forming the cut 5c, and the engaging piece 5d is provided by forming the cut 5c with this punch. The engaging piece 5d is a tongue-like piece having a tip provided in an arc shape. The cut 5 c and the engagement piece 5 d are provided at one corner of the paper 5. In this case, the second hole 5b is provided between the engaging piece 5d and the outer edge of the paper 5, and is separated from one edge of the first hole 5a by a predetermined distance. Further, as shown in FIG. 4B, the first hole 5a is formed in the paper 5 by providing the notch 5c. When the engaging piece 5d is bent at the base end portion 5e, the entire first hole 5a is opened. That is, the processing unit 16 forms the first hole 5a in the paper 5 as the engaging piece 5d is formed. Note that the first hole 5a shown in FIG. 4B and the first hole 5a shown in FIG. 3 are different in shape, but both are the first holes. The engaging piece 5d extends from the edge of the first hole 5a, specifically from the edge of the first hole 5a on the second hole 5b side.

  For convenience, the sheet 5 provided with the first hole 5a, the second hole 5b, and the engagement piece 5d shown in FIG. 4B is also referred to as a first sheet 5A. Further, the sheet 5 provided with the first hole 5a and the second hole 5b shown in FIG. 3 and without the engaging piece 5d is also referred to as a second sheet 5B. Here, the 1st hole 5a shown to FIG. 3 and FIG. 4 (B) may be a magnitude | size required in order to let the engagement piece 5d pass. For this reason, it is preferable to make it as small as possible and consider effective use of the image forming area. Here, the positions of the second holes 5b of the first sheet 5A and the second sheet B are the same. The position of one edge (the edge on the second hole 5b side) of the first hole 5a of the second sheet 5B coincides with the position of the base end part 5e of the engaging piece 5d of the first sheet 5A. Yes. The process part 16 of this embodiment forms the 1st hole 5a, the 2nd hole 5b, and the engagement piece 5d simultaneously as an example.

FIG. 5A is a plan view showing a second sheet with saddle stitching, and FIG. 5B is a plan view showing the first sheet with saddle stitching.
The saddle stitching process is performed at least two places symmetrically on the L part to be subjected to the middle folding process. FIG. 5A and FIG. 5B show diagrams in which saddle stitching is performed at four locations as an example. The saddle stitching process is also performed by the processing unit 16 that processes the paper 5 in the same manner as the edge binding process.

  FIG. 6 is a flowchart showing the flow of the edge binding process executed by the paper post-processing apparatus, and FIG. 7 is an exploded perspective view showing the paper bundle. 8A is a cross-sectional view showing the sheet bundle and the binding member in the first stage of the folding process in the binding process, and FIG. 8B is the sheet bundle and binding in the second stage of the folding process in the binding process. 8C is a cross-sectional view showing the sheet bundle and the binding member in the second hole passing process in the binding process, and FIG. 8D is a first stage of the pressing process in the binding process. FIG. 8E is a cross-sectional view showing the sheet bundle and the binding member in the second stage of the pressing step in the binding process. Further, FIG. 9A is a bottom view showing the sheet bundle in the end-bound state, FIG. 9B is a plan view showing the sheet bundle in the end-bound state, and FIG. 10 is FIG. 9B. It is sectional drawing which follows the A1-A1 line | wire.

The flow of the edge binding process will be described mainly with reference to the flowchart of FIG. 6 and other drawings.
When the entrance sensor 15 detects the carry-in of the paper 5 from the image forming apparatus 2, the processing unit 16 controlled by the control unit 61 punches the paper 5 (step S1). The punched paper 5 is transported to the paper stacking tray 23 by the transport unit 51 and stacked on the paper stacking tray 23 (step S2). As a result, a sheet bundle 6 is formed. Note that the processing in steps S1 and S2 is repeated for a predetermined number of sheets 5 instructed from the image forming apparatus 2. The control unit 61 counts the number of sheets 5 processed in steps S1 and S2 using the output of the entrance sensor 15.

  In step S1, as shown in FIG. 7, for example, the control unit 61 controls the processing unit 16 to provide the first hole 5a and the second hole 5b in each of the plurality of sheets 5, An engaging piece 5 d is provided on one or more of the sheets 5. Therefore, in the present embodiment, the sheet 5 on which the engagement pieces 5d are formed is carried into the first bundling unit 28. Here, the first hole 5a provided in the paper 5 is either one without the engaging piece 5d shown in FIG. 3 or one having the engaging piece 5d shown in FIG. 4 (B). At this time, the control unit 61 sets the processing unit 16 so that at least one of the pair of sheets 5 located at both ends of the sheet bundle 6 in the overlapping direction of the sheet bundle 6 has the engagement piece 5d. Control.

  Specifically, in the present embodiment, the control unit 61 causes the one sheet 5 of the pair of sheets 5 located at both ends of the sheet bundle 6 in the overlapping direction of the sheet bundle 6 to have the engagement piece 5d. The processing unit 16 is controlled. In the example of FIG. 7, the engagement piece 5 d is formed on the sheet 5 (the lowermost sheet 5 in FIG. 7) that is first processed by the processing unit 16 among the sheets 5 constituting the sheet bundle 6. Yes. In other words, in the present embodiment, the control unit 61 does not provide the engaging pieces 5 d on the other sheets 5 constituting the sheet bundle 6. That is, the sheet bundle 6 of the present embodiment is configured by stacking the first sheet 5A, the second sheet 5B, the second sheet 5B, the second sheet 5B, and the second sheet 5B from the bottom to the top. Has been.

  Here, the engaging piece 5d of the sheet bundle 6 constitutes an engaging portion 5f. In the present embodiment, the engaging portion 5f is configured by one engaging piece 5d. The engaging pieces 5d may be provided on a plurality of sheets 5, and the engaging portion 5f may be composed of two or more engaging pieces 5d stacked on each other in the sheet bundle 6. The control unit 61 controls the processing unit 16 so that the number of engaging pieces 5d in the engaging portion 5f is smaller than the number of sheets 5 constituting the sheet bundle 6.

  Next, the end binding unit 25 controlled by the control unit 61 performs binding (steps S3 to S5). First, the end binding part 25 performs folding of the engaging part 5f as a folding process (step S3). Specifically, as shown in FIG. 8A, the end binding portion 25 folds the engagement portion 5f by using the first binding member 25a as a first stage of the folding process, thereby making the engagement portion 5f a plurality of sheets. 5 is passed through the first hole 5a. Here, the first binding member 25a is formed in a shape that can be inserted into the first hole 5a. At this time, it is possible to improve the binding strength and the binding position accuracy by folding the first hole 5a so that one edge portion on the second hole 5b side is wound (a gap is eliminated as much as possible). Here, the first binding member 25a is an example of a first pressing member that pushes the engaging portion 5f and passes the engaging portion 5f through the first hole 5a. Next, as shown in FIG. 8B, the end binding portion 25 is arranged so that the engaging portion 5f is along one surface of the sheet bundle 6 by the second binding member 25b as the second stage of the folding process. Fold the engaging portion 5f.

  In step S4, the end binding portion 25 passes the engaging portion 5f through the second hole 5b as shown in FIG. 8C as the second hole passing step. Specifically, the end binding portion 25 pushes the engaging portion 5 f by the third binding member 25 c and passes the engaging portion 5 f through the second holes 5 b of the plurality of sheets 5. Here, the third binding member 25c is formed in a shape that can be inserted into the second hole 5b. The second pressing member is an example in which the engaging portion 5f passed through the first hole 5a is pushed and passed through the second hole 5b.

  In step S <b> 5, the end binding unit 25 keeps the front end side of the engagement unit 5 f along the other surface of the sheet bundle 6 as shown in FIG. 8D and FIG. Specifically, the end binding portion 25 pushes the engaging portion 5f by the fourth binding member 25d while rotating the fourth binding member 25d, and the leading end side of the engaging portion 5f is aligned with the other surface of the sheet bundle 6. The Thereby, the sheet bundle 6 is bound by the engaging portion 5f. Here, in the present embodiment, the end binding portion 25 presses the engagement portion 5f in a state in which the sheet bundle 6 is bound by the fourth binding member 25d and the second binding member 25b. Thereby, the binding by the engaging portion 5f is strengthened. 9A, 9B, and 10 show the sheet bundle 6 bound by the engaging portion 5f.

  As described above, the end binding portion 25 of the present embodiment passes through the first hole 5a the engaging portion 5f including one or two engaging pieces 5d overlapped with each other in the sheet bundle 6. The engaging portion 5f passed through the first hole 5a is passed through the second hole 5b, and the sheet bundle 6 is bound.

  FIG. 11 is a plan view showing the sheet bundle and the binding member during the binding process. As shown in FIG. 11, the width in the short direction of the second hole 5b is W1, and the width along the short direction of the second hole 5b in the third binding member (second pressing member) 25c is W2. The thickness of the sheet 5 is T, and the number of engagement pieces 5d in the engagement portion 5f is N. In this case, the width W1 is substantially the same as the value obtained by the width W2 + T × N × 2. Thereby, the fastening property of the engaging piece 5d and the second hole 5b can be improved. The width W3 in the direction orthogonal to the extending direction of the engaging piece 5d, the width W4 in the longitudinal direction of the second hole 5b, and the second hole in the third binding member (second pressing member) 25c. The width W5 along the longitudinal direction of 5b is substantially the same. Thereby, each paper 5 becomes difficult to shift.

  Returning to the flowchart of FIG. When the binding in steps S3 to S5 is completed, the sheet bundle 6 bound by the conveyance unit 51 controlled by the control unit 61 is discharged to the first discharge tray 10 (step S6).

  As described above, the sheet post-processing apparatus 3 according to the present embodiment is provided with the first hole 5a and the second hole 5b in each of the plurality of sheets 5, and the engagement piece 5d on one or more of the plurality of sheets 5. Is provided. Then, the engaging portion 5f composed of one or two or more engaging pieces 5d overlapped with each other in a state where the plurality of sheets 5 are overlapped is passed through the first hole 5a and then passed through the second hole 5b. As a result, a sheet bundle 6 composed of a plurality of sheets 5 is bound. The number of engagement pieces 5d in the engagement portion 5f is smaller than the number of sheets 5 constituting the sheet bundle 6. In the present embodiment, as an example, the number of sheets 5 constituting the sheet bundle 6 is five, whereas the number of engagement pieces 5d constituting the engagement portion 5f is one.

  The sheet bundle 6 produced in this way is provided with engagement pieces 5d on one or more of a plurality of sheets 5 stacked on each other, and is composed of one or two or more engagement pieces 5d stacked on each other. The engaging portion 5 f passes through the plurality of sheets 5 and binds the plurality of sheets 5. The number of engaging pieces 5d in the engaging portion 5f is smaller than the number of sheets of the plurality of sheets 5.

  As described above, in the present embodiment, the number of engagement pieces 5d in the engagement portion 5f is smaller than the number of the plurality of sheets 5 constituting the sheet bundle 6. Therefore, it can suppress that the thickness of the binding part of the sheet bundle 6 becomes thick. Therefore, an increase in the thickness of the stack of the sheet bundles 6 can be reduced when the sheets are stacked on the first discharge tray 10. Further, in the present embodiment, since the engaging portion 5f is constituted by one engaging piece 5d, it is possible to suppress the thickness of the sheet bundle 6 from increasing further. Although an example of edge binding has been mainly described, the same binding process as that for edge binding is performed in the case of saddle stitching.

  Here, when the sheet bundle 6 subjected to the saddle stitching process is folded in half, the larger the number of the sheet bundle 6 is, the longer the length from the L portion to the end face that is folded in the inner sheet 5 and the outer sheet 5. Will change. Therefore, if the punching positions of the first holes 5a ′ are the same in all the sheets 5, the outer sheet 5 is pulled when the center folding process is performed, and the second discharge due to the breakage due to the holes being broken or being broken. The paper 5 (paper bundle 6) is caught on the path to the paper tray 10 until the paper tray 10 is transported, resulting in paper jams and poor transportation.

  Therefore, in the present embodiment, the paper stop position in the processing unit 16 that forms a hole or the like in the paper 5 is varied for each paper 5, and the processing position is shifted. FIG. 12 is an exploded perspective view showing a sheet bundle in which the punching position is shifted. The first sheet 5A ′ accompanied by the engaging piece 5d ′ is conveyed from the conveying unit 51 to the sheet stacking tray 23, and then the second sheet 5B ′ not accompanied by the engaging piece 5d ′ is conveyed. Here, the third sheet of the paper 5B ′ conveyed to the paper stacking tray 23 is processed with a slight shift to a position away from the L portion where the folding process is performed. For example, after the leading edge of the sheet 5 is detected by the inlet sensor 15, the control for shifting the processing is performed by changing the number of control pulses of the inlet motor in order to shift the stop timing of the inlet motor (not shown) that drives the inlet roller 11. Do.

  Further, when the thick paper is set on the operation panel of the image forming apparatus 2 and the paper 5 is conveyed to the paper post-processing apparatus 3, the paper thickness information from the image forming apparatus 2 is received and the distance for shifting the punching is increased. By doing so, even when the middle folding process is performed with thick paper, the inner and outer hole positions can be reliably aligned during the middle folding, and no binding failure or conveyance failure occurs during the middle folding.

  Further, a sheet thickness detecting means may be provided in the sheet post-processing apparatus 3. The sheet thickness detection means uses an ultrasonic sensor and is mounted between the inlet sensor 15 and the processing portion 16 for forming a hole or the like.

  FIG. 13 is a diagram showing the principle of detection by the paper thickness detection means. The ultrasonic sensor 111 includes a wave transmitter 111a and a wave receiver 111b. An ultrasonic wave (Us1: indicated by a thick line in the figure) is transmitted to the paper 5 by the wave transmitting part 111a, and an ultrasonic wave (Us2: indicated by a thin line in the figure) that has passed through the paper 5 is received by the wave receiving part 111b. Receive. The ultrasonic wave transmitted from the wave transmission unit 111a is attenuated when passing through the paper 5, and is received by the wave reception unit 111b. If the paper used is of the same material and has a different thickness, the attenuation amount or the degree of attenuation of the ultrasonic wave varies depending on the paper thickness of the paper 5. That is, the level received by the wave receiver 111b changes. For this reason, the punching position can be changed according to the thickness of the paper 5 depending on the received value.

  For example, when a sheet 5 having a paper thickness of X mm is conveyed, the punching position is shifted by Z mm, and when a sheet 5 (paper thickness X ′ mm) thinner than X mm is conveyed, the position is shifted by Z ′ mm. (Z> Z ′). The direction of shifting Zmm is the direction away from the L portion that is subjected to the middle folding process. The amount by which the punching position is shifted with respect to each paper thickness is stored in the storage unit of the control unit 61 of the paper post-processing apparatus 3, and the paper thickness is determined for the first sheet of the paper 5 conveyed from the image forming apparatus 2. Judgment can be made to change the drilling position.

  Further, the number of sheets on which the engagement pieces 5d 'are provided may be changed according to the sheet thickness or the number of sheets. For example, when a sheet 5 having a paper thickness of X mm is conveyed, the number of sheets on which the engagement pieces 5d ′ are provided is n, and a sheet 5 (paper thickness X ′ mm) thinner than X mm is conveyed. In this case, the number of sheets on which the engaging piece 5d ′ is provided is set to be less than n. The paper thickness is detected by the above-described paper thickness detection means or other detection means. The number of sheets on which the engagement piece 5d ′ is provided with respect to the sheet thickness is stored in the storage unit of the control unit 61 of the sheet post-processing device 3, and is determined by the first sheet of the sheet 5 conveyed from the image forming apparatus 2. To decide.

  Further, when the number of sheet bundles is large, the number of sheets 5 on which the engagement pieces 5d 'are provided can be increased. The number of sheets 5 constituting the sheet bundle can be determined by the number of processed sheets sent from the image forming apparatus 2. For example, when binding a sheet bundle of 50 sheets, the number of sheets on which the engagement pieces 5d ′ are provided is n sheets, and when binding a sheet bundle of 30 sheets, the number of sheets on which the engagement pieces 5d ′ are provided is less than n sheets. can do. The number of sheets on which the engagement piece 5d 'is provided may be stored in the storage unit of the control unit 61 of the sheet post-processing apparatus 3 and determined based on the number of processed sheets sent from the image forming apparatus 2.

  That is, by shifting the positions of the holes for each sheet, the inner and outer hole positions can be matched during the middle folding, so that no binding failure or conveyance failure can occur during the middle folding. In addition, by shifting the punching position for each paper thickness, the inner and outer hole positions can be matched in any sheet, so that no binding failure or conveyance failure occurs during the middle folding. Even if the number of sheets is large, the strength at the time of binding can be increased by increasing the number of sheets on which the engagement pieces are provided, and it is possible to prevent the occurrence of binding failure and conveyance failure at the time of middle folding.

  The “paper” is not limited to paper as long as it is a sheet-like material and can be perforated, and any “paper” may be used. For example, those made of plastic are known as those used in the image forming apparatus, but various other materials can be used.

  The present invention is not limited to the embodiments described above, and many variations are possible by those having ordinary knowledge in the art within the technical idea of the present invention.

1: Image forming system 2: Image forming device 3: Paper post-processing device 5: Paper 5A: First paper 5B: Second paper 5a: First hole 5b: Second hole 5c: Cut 5d: Engagement piece 5e: base end portion 5f of engaging piece: engaging portion 6: sheet bundle 10: discharge tray 11: entrance rollers 12-14: discharge rollers 15: entrance sensor 16: processing portion 16a: punch portion 16b: dice portion 17: Branch claw 20: Conveying roller 23: Paper stacking tray 24: First jogger fence 25: End binding unit 26: Branch claw 28: First bundling unit 31: Conveying roller 33: Folding unit 34: Middle folding unit 35 : Saddle stitching part 36: Second bundling part 37: Second movable reference fence 38: Blades 39, 40, 41: Roller 42: Second paper discharge tray 51: Conveying part 52: Path switching part 61: Control Part 111: Ultrasonic sensor 111a: transmitting unit 111b: reception portion Pt1: first conveying path Pt1: conveying path Pt2: second conveyance path Pt3: third transport path X: sheet thickness

JP 2011-201698 A

Claims (7)

A processing unit capable of providing a first hole in the paper, providing a second hole in the paper, and providing an engagement piece in the paper by cutting the paper;
A control unit that controls the processing unit to provide the first hole and the second hole in each of a plurality of sheets, and to provide the engagement piece in one or more of the plurality of sheets;
A bundling unit that stacks the plurality of sheets to form a sheet bundle;
The engaging portion composed of one or two or more engaging pieces stacked on each other in the sheet bundle is passed through the first hole, and the engaging portion passed through the first hole is used as the second hole. A sheet binding portion for binding the sheet bundle;
A center folding section for folding the sheet bundle that has undergone saddle stitching in the sheet binding section;
With
The control unit performs control to enable perforation by shifting the positions of the first hole and the second hole for each sheet so that the holes of each sheet are aligned when the sheet bundle is folded.
A sheet post-processing apparatus. The paper post-processing apparatus according to claim 1.
A paper thickness detecting means for detecting the thickness of the paper;
The paper post-processing apparatus, wherein the control unit performs control to vary a shift amount of the punching position in accordance with the paper thickness detected by the paper thickness detecting means. In the paper post-processing apparatus according to claim 1 or 2,
The sheet post-processing apparatus, wherein the control unit performs control to vary the number of sheets on which the engagement piece is provided according to the number of sheets forming the sheet bundle. In the paper post-processing apparatus according to any one of claims 1 to 3,
The processed portion is
At least one of the sheets forming the sheet bundle is cut in a half-cut shape to form the engaging piece and the first hole is provided.
The other sheets forming the sheet bundle are provided with the first hole and the second hole,
Bending the engagement piece of the paper provided with the cut and the first hole at the base end, and passing it through the second hole of the other paper provided with the first hole and the second hole,
Thereafter, a binding process is performed in which the engagement pieces are bound through the first holes of all sheets.
A sheet post-processing apparatus. The paper post-processing apparatus according to claim 4,
The first hole and the second hole are shifted for each sheet, and the first hole and the second hole of each sheet are aligned after the sheet bundle is folded. ,
A sheet post-processing apparatus. In the paper post-processing apparatus according to any one of claims 1 to 5,
The engagement piece has a U-shape;
A sheet post-processing apparatus. An image forming system comprising the sheet post-processing apparatus according to claim 1 and an image forming apparatus that discharges the sheet to the sheet post-processing apparatus.