Post-processing device and image formation system

Abstract

To provide a post-processing device and an image forming system in which the paper order of a booklet is permuted.SOLUTION: A first conveyance path that conveys a sheet sent from an image forming means downstream; a second conveyance path that branches off from the first conveyance path and can be retracted from the first conveyance path and temporarily retained by reversing and conveying the sheet in a direction opposite to the downstream; and a sheet placement means arranged so that a placement surface where sheets are overlapped and placed as a sheet bundle on a downstream side of the second conveyance path in a reverse conveyance direction of the second conveyance path face up and is inclined in a sheet conveyance direction of the first conveyance path; are provided.SELECTED DRAWING: Figure 4

Description

Technical Field

[0001] The present invention relates to a post-processing device and an image forming system.

Background Art

[0002] There is known a post-processing device having a paper bundle forming unit that bundles a plurality of sheets to form a paper bundle, a binding means that penetrates the paper bundle formed by the paper bundle forming unit with a binding needle and bends an end portion of the binding needle to bind the paper bundle, a folding means that folds a portion of the paper bundle bound by the binding needle, and a binding needle detection unit that is disposed on the downstream side in the paper bundle conveyance direction from the binding means and on the upstream side in the paper bundle conveyance direction from the folding means and detects the binding needle used for the paper bundle by the binding means (Patent Document 1).

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] The present invention provides a post-processing device and an image forming system in which the paper order of a booklet is a permutation.

Means for Solving the Problems

[0005] In order to solve the above problems, The 1 manner the post-processing device includes a buffer unit that conveys a plurality of sheets sent from an image forming unit while overlapping them, and a compile tray in which the sheets supplied from the buffer unit are overlapped and a placement surface on which the sheets are placed as a paper bundle is inclined in a direction opposite to the conveyance direction of the sheets in the buffer unit with the carry-in side of the sheets facing upward. It is characterized by the above.

[0006] The 2 Post-processing apparatus for the configuration teeth, The 1 manner In the post-processing equipment, The buffer unit transports the paper sent from the image forming means to the aforementioned surface, stacking multiple sheets in order from top to bottom. It is characterized by the following:

[0007] The 3 Post-processing apparatus for the configuration teeth, First aspect In the post-processing equipment, The buffer section includes a first transport path that transports the paper sent from the image forming means downstream, It consists of a second transport path that branches off from the first transport path and allows the paper to be transported in the opposite direction to the downstream direction, thereby enabling it to be moved away from the first transport path and temporarily stored there, The compilation tray is positioned downstream of the second transport path in the reverse transport direction, and the sheets are placed on the aforementioned surface in a permuted order. It is characterized by the following:

[0008] The 4 Post-processing apparatus for the configuration teeth, The 3 manner In the post-processing equipment, The buffer unit transports the paper sent from the image forming means to the aforementioned surface, stacking multiple sheets of paper from the bottom upwards. It is characterized by the following:

[0009] The 5 Post-processing apparatus for the configuration teeth, The 3 manner In the post-processing equipment, The buffer unit sequentially inverts and transports each sheet of paper sent from the image forming means, stacking them in order from the bottom, and transporting them to the aforementioned surface. It is characterized by the following:

[0010] The 6 Post-processing apparatus for the configuration teeth, The 1 manner or The 5 manner any one of 1 aspect in the post-processing device of the paper conveyed in a stacked manner by the buffer part is two sheets of paper characterized by this

[0011] To solve the above problems The 7 manner the image forming system of an image forming device that forms an image on paper, a post-processing device that performs intermediate binding on the stack of papers on which the image has been formed by the image forming device The 1 manner to The 6 manner any one of manner and is provided with characterized by this

Effect of the Invention

[0012] The 1 Post-processing apparatus for the configuration , The 7 Image forming system for different types According to, even when a buffer function is provided in the post-processing device, the paper order of the booklet becomes a permutation regardless of the number of buffer sheets for buffering.

[0013] The 2 manner of Post-processing equipment According to, the buffer area can be on the upper side.

[0014] The 3 manner of Post-processing equipment According to, even when a buffer function is provided in the post-processing device, the paper order of the booklet becomes a permutation regardless of the number of buffer sheets for buffering.

[0015] The 4 manner of Post-processing equipment According to, the buffer area can be on the lower side.

[0016] The 5 manner of Post-processing equipment According to this, the buffer can be miniaturized.

[0017] The 6 manner of Post-processing equipment According to this, it is possible to suppress the decline in productivity during post-processing. [Brief explanation of the drawing]

[0018] [Figure 1] This is a schematic diagram showing an image forming system to which the post-processing device according to this embodiment is applied. [Figure 2] This diagram illustrates the functions of the post-processing device according to this embodiment. [Figure 3] This is a diagram illustrating the paper transport process in the finisher unit. [Figure 4] This diagram illustrates the configuration of the saddle-stitch binding function unit according to this embodiment. [Figure 5] This diagram illustrates the paper transport and paper placement on the mounting surface during the compilation operation of the saddle-stitch binding function unit according to this embodiment. [Figure 6] This diagram illustrates the configuration of the saddle-stitch binding function unit in a comparative example. [Figure 7] This diagram illustrates the paper transport and paper placement on the mounting surface during the compilation operation of the saddle-stitch binding function unit in the comparative example. [Modes for carrying out the invention]

[0019] The present invention will now be described in more detail with reference to the drawings, with examples of embodiments and specific examples provided below, but the present invention is not limited to these embodiments and specific examples. Furthermore, it should be noted that the following diagrams used in the explanation are schematic, and the proportions of the dimensions may differ from those of reality. For ease of understanding, diagrams of components other than those necessary for the explanation have been omitted as appropriate.

[0020] (1) Overall configuration and operation of the image forming system Figure 1 is a schematic diagram showing an image forming system 100 to which the post-processing device according to this embodiment is applied. The image forming system 100 shown in Figure 1 comprises an image forming device 1, such as a printer or copier, which forms an image by electrophotography, and a post-processing device 2 that performs post-processing on the paper P on which a toner image has been formed by the image forming device 1.

[0021] The image forming apparatus 1 includes an image forming unit 10 that forms an image based on image data, an image reading unit 11 that reads an image from a document and generates read image data, a paper supply unit 12 that supplies paper P to the image forming unit 10, a user interface 13 that accepts operation input from the user and displays various information to the user of the image forming system 100, and a control unit 14 that controls the operation of the entire image forming system 100.

[0022] The image forming unit 10 includes a photoreceptor, and around the photoreceptor are a charging device that uniformly charges the photoreceptor, an exposure unit that scans a light beam based on image data, a developing unit that develops the electrostatic latent image formed by scanning exposure by the exposure unit with toner, a transfer unit that transfers the toner image on the developed photoreceptor to the paper P, and a cleaning unit that cleans the surface of the photoreceptor after transfer. Furthermore, a fixing unit is provided on the transport path of the paper P to fix the toner image on the paper P after transfer.

[0023] The post-processing device 2 includes a transport unit 3 that receives and transports the paper P with an image formed on it from the image forming apparatus 1, a folding unit 4 that performs folding on the paper P brought in from the transport unit 3, and a finisher unit 5 that performs final processing on the paper P that has passed through the folding unit 4. Furthermore, the system includes an interposer 6 that supplies interleaving paper for forming the cover of the booklet, and a paper processing control unit 7 that controls each functional part of the post-processing device 2. In Figure 1, the post-processing device 2 is shown with the paper processing control unit 7 located within the post-processing device 2, but the paper processing control unit 7 may also be located within the image forming apparatus 1. Alternatively, the control unit 14 in the image forming apparatus 1 that controls the operation of the entire image forming system 100 may also have the control function of the paper processing control unit 7.

[0024] (2) Post-processing equipment Figure 2 is a diagram illustrating the function of the post-processing device 2, and Figure 3 is a diagram illustrating the transport of paper P in the finisher unit 5. The post-processing device 2 includes a punching function unit 70 that punches holes such as 2 holes or 4 holes in the paper P, an edge-stitching function unit 40 that stacks the required number of paper bundles PB to create a paper bundle PB (see Figure 4) and performs a binding process (edge ​​stitching) at the ends of the paper bundle PB, and a saddle-stitching binding function unit 30 that stacks the required number of paper P to create a paper bundle PB and binds the central part of the paper bundle PB into a booklet.

[0025] The finisher unit 5 has a paper transport section downstream of the receiving roller 47 that receives the paper P fed in via the discharge roll 46 of the folding unit 4, and includes a first paper transport path R1, a second paper transport path R2, and a third paper transport path R3. The first paper transport path R1, the second paper transport path R2, and the third paper transport path R3 are selected by a switching gate G1 (see Figure 3).

[0026] The first paper transport path R1 transports the paper P fed from the receiving roller 47 to the edge stapling function unit 40 (paper transport direction D1 in Figure 3). The second paper transport path R2 branches off from the first paper transport path R1 and is connected to the saddle-stitch binding function unit 30, and the booklets created by the saddle-stitch binding function unit 30 are discharged into the booklet tray TR3 (see Figure 2). The second paper transport path R2 also temporarily holds the paper P that is transported in reverse within the first paper transport path R1 (paper transport direction D2 in Figure 3), and in this embodiment, the first paper transport path R1 and the second paper transport path R2 constitute a buffer section that transports multiple sheets of paper P stacked on top of each other. The third paper transport path R3 branches off from the first paper transport path R1 and connects to the top tray TR1 (see Figure 2). Paper P that does not undergo post-processing is discharged from this third paper transport path R3 (paper transport direction D3 in Figure 3).

[0027] Furthermore, the folding unit 4 is equipped with a folding function section 50 that performs folds such as inward tri-folds (C-folds) and outward tri-folds (Z-folds) on the paper P. Furthermore, the interposer 6 and transport unit 3 are equipped with a paper supply function unit 90 that supplies interleaving paper such as cardboard or windowed paper used for the cover of the paper bundle PB.

[0028] (2.1) Configuration of the saddle-stitch binding function Figure 4 is a diagram illustrating the configuration of the saddle-stitch binding function unit 30 according to this embodiment. As shown in Figure 4, the saddle-stitch binding function unit 30, which binds a stack of paper PB into a booklet, includes a compile tray 31 that collects a predetermined number of sheets of paper P after image formation, a loading roller 39 that loads the paper P into the compile tray 31 one sheet at a time, and an end guide 32 that places the stack of paper PB on a positioning stopper protruding from the compile tray 31 and moves along the compile tray 31 to determine the saddle-stitch and folding positions of the stack of paper B. Furthermore, it includes a paper alignment paddle 33 for aligning the paper P accumulated on the compile tray 31 toward the end guide 32, and a paper width alignment member 34 for aligning the width direction of the paper P accumulated on the compile tray 31.

[0029] Furthermore, the saddle-stitch binding function unit 30 includes a stapler 80 that performs a binding process on the stack of paper PB accumulated on the compile tray 31 while passing a stapling needle through it, a folding mechanism 35 having a folding knife 35a that moves so as to protrude from the back side of the compile tray 31 toward the storage side relative to the bound stack of paper PB, and a folding roller 36 consisting of a pair of rollers that grips the stack of paper B as folding begins with the folding knife 35a. Furthermore, downstream of the folding roller 36, there is a transport roller 37 for transporting the paper bundle PB that has been folded and bound by the folding mechanism 35 and the folding roller 36, a booklet tray TR3 for loading the bound paper bundle PB, and an output roller 38 for transporting the paper bundle PB to the booklet tray TR3.

[0030] In this embodiment, as shown in Figure 4, the saddle-stitch binding function unit 30 has a compile tray 31 positioned with the paper input side of the paper P facing upwards (Z direction in the figure) and tilted in the opposite direction to the paper transport direction D2 in the first paper transport path R1. That is, if we consider a vertical line V1 passing through the second paper transport path R2, the upper end 31b of the compile tray 31 is tilted (indicated by X in Figure 4) to the downstream side of the paper transport direction D1 in the first paper transport path R1 relative to the vertical line V1. As a result, the mounting surface 31a on which the paper sheets P are placed as a stack of paper sheets PB is on the opposite side from which the folded stack of paper sheets PB is discharged, and the paper sheets P that are transported in reverse from the second paper transport path R2 are placed on the mounting surface 31a in a permuted order.

[0031] (2.2) Compilation operation of the saddle-stitch binding function Figure 6 illustrates the configuration of the saddle-stitch binding function unit 30A in the comparative example, in which the compile tray 31A is positioned with the paper input side of the paper P facing upwards (Z direction in the figure) and is tilted in the opposite direction to the paper transport direction D1 of the first paper transport path R1. Figure 7 illustrates the paper transport and the state of placement of the paper P on the placement surface 31Aa during the compile operation of the saddle-stitch binding function unit 30A in the comparative example.

[0032] In the comparative example, the saddle-stitch binding function unit 30A is inclined such that, when a vertical line V1 passing through the second paper transport path R2 is assumed, the upper end 31b of the compile tray 31A is located upstream of the vertical line V1 in the paper transport direction D1 of the paper P in the first paper transport path R1 (indicated as -X in Figure 6). As a result, the mounting surface 31Aa on which the paper sheets P are placed as a stack of paper sheets PB becomes the side from which the folded stack of paper sheets PB is discharged, and the paper sheets P that are transported one by one from the second paper transport path R2 are placed on the mounting surface 31Aa in a permuted order.

[0033] On the other hand, as shown in Figure 7, if paper buffering is performed by switchback (reverse transport) in the buffer section, the order in which the sheets of paper P are stacked on the mounting surface 31Aa will not be permutations.

[0034] For example, when performing a single-sheet paper buffer (only at the beginning of a paper stack set), the first sheet of paper P1 is reversed and temporarily held in the second paper transport path R2, which acts as a buffer (see Figure 7(a)). At the same time that the second sheet of paper P2 is transported into the first paper transport path R1, the first sheet of paper P1, which is held in the second paper transport path R2, is transported in the opposite direction into the first paper transport path R1 (see Figure 7(b)). Then, the first sheet of paper P1 and the second sheet of paper P2, which constitute a single buffer, are transported together in the second paper transport path R2 to the compile tray 31A at the same time (see Figure 7(c)).

[0035] Next, the third sheet of paper P3 is reversed from the first paper transport path R1 and transported through the second paper transport path R2 to the compile tray 31A (see Figure 7(d)). In this way, when a single-sheet paper buffer is performed, the order in which the sheets of paper P are compiled is the second sheet, the first sheet, and the third sheet, starting from the mounting surface 31Aa side, and is not in a permutation order.

[0036] Similarly, if a two-sheet paper buffer is used (only at the beginning of the paper stack set), the order in which the sheets P are compiled will be the 3rd, 2nd, 1st, and 4th sheets from the mounting surface 31Aa side, and will not be in a permutation order. Therefore, in order to speed up saddle stitching as a post-processing step, if paper buffering is used, it is necessary to change the order of the paper sheets P on the image forming apparatus 1 side, for example.

[0037] Figure 5 shows the paper transport and the state of the paper P being placed on the mounting surface 31a during the compilation operation of the saddle-stitch binding function unit 30 according to this embodiment. For example, when buffering one sheet of paper (only the beginning of a paper stack), the first sheet of paper P1 is reversed and temporarily held in the second paper transport path R2, which acts as a buffer (see Figure 5(a)). At the same time that the second sheet of paper P2 is transported into the first paper transport path R1, the first sheet of paper P1, which was held in the second paper transport path R2, is transported in the opposite direction into the first paper transport path R1 (see Figure 5(b)). Then, when the first sheet of paper P1 and the second sheet of paper P2, which constitute a single buffer, are transported simultaneously and overlapping through the second paper transport path R2 to the compile tray 31, the first sheet of paper P1 will be on the placement surface 31a side, and the second sheet of paper P2 will be placed on top of it (see Figure 5(c)).

[0038] Next, the third sheet of paper P3 is reversed from the first paper transport path R1 and transported through the second paper transport path R2 to the compile tray 31, so that the third sheet of paper P3 is placed on top of the second sheet of paper P2 (see Figure 5(d)). In this way, even with a single-sheet buffer, the order in which the sheets of paper P are compiled is permutation, with the first sheet being the first, the second, and the third sheet being the third, starting from the mounting surface 31a side.

[0039] Similarly, when a two-sheet paper buffer is used (only at the beginning of the paper stack set), the order in which the sheets P are compiled will be the 1st, 2nd, 3rd, and 4th sheets, starting from the mounting surface 31a, and will be in a permutation order. If paper buffering is not performed, the sheets of paper P transported one by one from the second paper transport path R2 are placed on the mounting surface 31a in a permutation order, such as the first sheet, second sheet, third sheet, and so on.

[0040] Thus, according to this embodiment, the compile tray 31 is positioned with the paper input side of the paper P facing upwards (Z direction in the figure) and tilted in the opposite direction to the paper transport direction D2 in the first paper transport path R1, and the paper P is placed on the mounting surface 31a where the paper stack PB is placed, stacked in such a permutation order when a paper buffer is applied. [Explanation of Symbols]

[0041] 100...Image forming system 1. Image forming apparatus 10...Image forming unit, 11...Image reading unit, 12...Paper supply unit 13. User Interface, 14. Control Unit 2. Post-treatment device 3. Transport Unit 4-fold unit 5. Finisher Unit R1...First paper transport path, R2...Second paper transport path 30, 30A...Saddle-stitch binding function 31, 31A... Compile tray, 32... End guide 35...Folding mechanism, 36...Folding rollers 6. Interposer 7. Paper Processing Control Unit

Claims

1. A buffer unit stacks multiple sheets of paper that are transported from the image forming means in the transport direction, starting from the bottom, and transports them in the opposite direction to the transport direction to discharge them downwards. The compilation tray comprises a surface on which the paper loaded from the buffer section is stacked and placed as a stack of paper, with the loading side of the paper facing upwards and the tray tilted in the transport direction, The mounting surface extends in a direction that intersects the paper loading direction when viewed from the width direction of the paper accumulated on the compile tray. A post-processing apparatus characterized by the following:

2. The buffer section includes a first transport path that transports the paper transported from the image forming means downstream in the transport direction, It consists of a second transport path that branches off from the first transport path and allows the paper to be transported in the opposite direction to the transport direction, thereby enabling it to be moved away from the first transport path and to be temporarily stored there, The compilation tray is positioned on the opposite side of the second transport path from the branching portion of the second transport path from the first transport path, and the sheets are placed on the aforementioned surface in a permutation order. The post-processing apparatus according to feature 1.

3. The buffer unit transports the preceding paper, which has been transported to the second transport path prior to the following paper, to the first transport path in time with the timing at which the following paper transported from the image forming means is transported to the first transport path. The preceding paper, which has been transported from the image forming means to the first transport path, is reversed and transported to be temporarily held in the second transport path. The buffer section temporarily holds the paper in the second transport path by reversing the paper that has been transported one sheet at a time to the first transport path to the second transport path until the planned number of sheets to be stacked is reached. The post-processing apparatus according to claim 2.

4. The upper end of the aforementioned mounting surface of the compile tray is located downstream in the transport direction with respect to the vertical line passing through the lower end of the second transport path, and the lower end of the aforementioned mounting surface is located upstream in the transport direction with respect to the vertical line. The post-processing apparatus according to claim 2.

5. It consists of paddles and further includes a feeding roller for transporting the paper from the buffer section to the compile tray, The post-processing apparatus according to claim 1.

6. The paper that is transported in stacks by the buffer section is two sheets of paper. The post-processing apparatus according to any one of claims 1 to 5.

7. A buffer section comprises a stack of paper sheets, each sheet being transported one by one in the transport direction from an image forming means. The buffer section transports multiple sheets, including the first sheet, in a sequential manner in the opposite direction to the transport direction and discharges them downwards, while the remaining sheets are transported one by one in the opposite direction to the transport direction and discharged downwards. The compilation tray comprises a surface on which the stacked sheets of paper, which are fed downward from the buffer section, are placed as a stack of paper, and the surface on which the stacked sheets are placed is inclined in the transport direction with the paper feeding side facing upward, The buffer section is characterized by stacking multiple sheets, including the leading sheet, so that when multiple sheets, including the leading sheet, are discharged to the compile tray, the leading sheet is transported with the leading sheet facing the aforementioned mounting surface.

8. An image forming apparatus that forms an image on paper, A post-processing device according to any one of claims 1 to 7, which performs saddle stitching on a stack of paper on which an image has been formed by the image forming apparatus, is provided, An image forming system characterized by the following features.

Images