Post-processing device and image formation system

Abstract

To provide a post-processing device that can distribute positions of binding parts in the load, suppress the collapse of the load and the reduction of a loading capacity, and allow a user to easily align the front and back of bound paper bundles.SOLUTION: A post-processing device according to the present invention includes binding means for binding a plurality of printed matters to form a binding part to form a bundle of printed matters, loading means for loading the bundle of printed matters, and a control unit. A selectable method is provided: a method 1 for loading the bundle of printed matters on the loading means with one side of the printed matters facing up; and a method 2 for loading the bundle of printed matters on the loading means with the other side of the printed materials facing up. The positions of the binding parts when loaded on the loading means are different between the methods 1 and 2. The number of copies of the bundle of printed matters to be continuously loaded using the method 1 or the method 2 can be set by a user, and the number of copies set by the user is designated as the number of copies X. The control unit controls the bundle of printed matters to be loaded by switching between the method 1 and the method 2 for each number of copies X.SELECTED DRAWING: Figure 9

Description

[Technical field]

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

[0002] 2. Description of the Related Art There is known an image forming system that performs a process of binding a plurality of printed sheets on which images have been formed, and stacks the bound printed sheets.

[0003] In such an image forming system, when the sheets are stacked, the positions of the bound parts overlap, causing the position of the stack to be locally high. In this case, the stack may collapse, and the ejection of the printed sheets may be hindered, resulting in a decrease in the stack amount.

[0004] Patent Document 1 discloses an image forming apparatus including a reversing means for reversing or not reversing a sheet on which an image is formed, a binding means for binding a stack of sheets, and a control means. The control means changes the front and back directions for each predetermined number of sheets bound by the binding means, and controls the binding positions of the sheet bundles so that the binding positions are approximately the same between the sheet bundles. According to Patent Document 1, when the sheets are discharged and stacked on the tray, only the overlapping parts of the stapled portions bulge, which prevents problems with tray storage caused by uneven thickness. Summary of the Invention [Problem to be solved by the invention]

[0005] However, in Patent Document 1, the paper is alternately discharged face up and back up, so if the user wants to align the front and back of the prints, they need to turn over each copy. In this case, aligning the front and back of the prints is time-consuming, and especially when a large number of prints are made, the work of aligning the front and back of the prints is extremely time-consuming. In addition, in Patent Document 1, the user cannot set the number of copies to be bound, and the user has to work harder to align the front and back of the prints depending on the number of copies to be bound.

[0006] Therefore, the present invention aims to provide a post-processing device that can disperse the positions of the stapled parts of the loaded items, prevent the loaded items from collapsing and the load capacity from decreasing, and allow the user to easily align the front and back of the stapled stack of paper. [Means for solving the problem]

[0007] In order to solve the above problems, the post-processing device of the present invention comprises: A binding means for binding a plurality of printed materials to form a bound portion and form a bundle of the printed materials; A stacking means for stacking the stack of printed matter; A post-processing device comprising: A method 1 in which the stack of printed materials is loaded on the loading means with one side of the printed materials facing up, and a method 2 in which the stack of printed materials is loaded on the loading means with the other side of the printed materials facing up can be selected, and the method 1 and the method 2 have different positions of the binding portion when the printed materials are loaded on the loading means, The number of copies of the bundle of printed materials to be continuously stacked in the method 1 or the method 2 can be set by a user, and the number of copies set by the user is designated as number of copies X; The control unit switches between the method 1 and the method 2 for each number of copies X and controls stacking of the bundle of printed materials. It is characterized by: Effect of the Invention

[0008] According to the present invention, it is possible to provide a post-processing device that can disperse the positions of the stapled parts of the loaded items, thereby preventing the loaded items from collapsing and reducing the load capacity, and allows the user to easily align the front and back of a stapled stack of paper. [Brief description of the drawings]

[0009] [Figure 1] FIG. 1 is a schematic diagram illustrating an example of an image forming system. [Diagram 2] FIG. 2 is a schematic diagram for explaining an example of a post-processing device. [Diagram 3]FIG. 2 is a diagram illustrating an example of a control block diagram of the image forming system. [Figure 4] FIG. 4 is another schematic diagram for explaining the example of the post-processing device. [Diagram 5] FIG. 4 is a schematic plan view for explaining an example of paper ejection. [Figure 6] FIG. 11 is a schematic plan view for explaining another example of paper discharge. [Figure 7] FIG. 13 is a diagram for explaining an example of a load. [Figure 8] 1A is a schematic plan view and FIG. 1B is a schematic side view for illustrating an example of a load. [Figure 9] FIG. 13 is a diagram for explaining another example of a load. [Figure 10] FIG. 11 is a diagram for explaining an example of a flow. [Figure 11] FIG. 13 is a diagram for explaining another example of a load. [Figure 12] FIG. 11 is a diagram for explaining another example of the flow. [Figure 13] FIG. 13 is a diagram for explaining another example of a load. [Figure 14] FIG. 13 is a diagram for explaining another example of a load. [Figure 15] FIG. 11 is a diagram for explaining another example of the flow. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] Hereinafter, a post-processing device and an image forming system according to the present invention will be described with reference to the drawings. Note that the present invention is not limited to the following embodiment, and can be modified within the scope of what a person skilled in the art can imagine, such as other embodiments, additions, modifications, deletions, etc., and any aspect is included in the scope of the present invention as long as it achieves the functions and effects of the present invention.

[0011] The post-treatment device of the present invention comprises: A binding means for binding a plurality of printed materials to form a bound portion and form a bundle of the printed materials; A stacking means for stacking the stack of printed matter; A post-processing device comprising: A method 1 in which the stack of printed materials is loaded on the loading means with one side of the printed materials facing up, and a method 2 in which the stack of printed materials is loaded on the loading means with the other side of the printed materials facing up can be selected, and the method 1 and the method 2 have different positions of the binding portion when the printed materials are loaded on the loading means, The number of copies of the bundle of printed materials to be continuously stacked in the method 1 or the method 2 can be set by a user, and the number of copies set by the user is designated as number of copies X; The control unit switches between the method 1 and the method 2 for each number of copies X and controls stacking of the bundle of printed materials. It is characterized by:

[0012] An image forming system of the present invention includes the post-processing device of the present invention and an image forming device, wherein the post-processing device receives the printed matter from the image forming device.

[0013] In this embodiment, it is possible to select between method 1, in which a stack of printed materials is loaded on the loading means with one side of the printed materials facing up, and method 2, in which a stack of printed materials is loaded on the loading means with the other side of the printed materials facing up. Methods 1 and 2 differ in the position of the binding portion when loaded on the loading means. This makes it possible to prevent the stacked objects loaded on the loading means from becoming locally high. It is also possible to prevent the load amount from decreasing, and to prevent the stacked objects from collapsing.

[0014] Furthermore, in this embodiment, the user can set the number of copies of a stack of printed materials to be continuously stacked using method 1 or method 2, and the number of copies set by the user is designated as number of copies X. Then, the stack of printed materials is stacked by switching between method 1 and method 2 for each number of copies X. This allows the user to easily align the front and back of the bound stack of papers.

[0015] A stack of printed matter loaded on a loading means is also referred to as a stack. A stack of printed matter is also referred to as a stack of loaded paper, a sheet stack, etc. A stack of printed matter is measured in units of copies. For example, when there are two stacks of printed matter, they are also referred to as two copies. One side of a printed matter may be referred to as the front side, and the other side of a printed matter may be referred to as the back side. A printed matter is, for example, a sheet of paper on which an image has been formed. As described below, a post-processing device receives printed matter from an image forming device. A printed matter may include a case where no image has been formed.

[0016] FIG. 1 is a schematic diagram for explaining an example of an image forming system according to the present embodiment. The image forming system 100 of this embodiment includes an image forming apparatus 101 and a post-processing apparatus 102. The image forming apparatus 101 and the post-processing apparatus 102 are connected to each other so that they can communicate with each other. The post-processing apparatus 102 may be called a paper processing apparatus, a paper post-processing apparatus, or the like.

[0017] The image forming apparatus 101 forms an image on a recording medium (for example, paper) to form a printout. The formation of an image may also be called printing, printing, or the like.

[0018] The post-processing device 102 receives printed matter from the image forming device 101 and performs post-processing on the received printed matter. Examples of post-processing include paper alignment, edge binding, and punching. The post-processing device 102 may perform one or more post-processing processes.

[0019] FIG. 2 is a schematic diagram for explaining an example of the post-processing device 102. As shown in FIG. The post-processing device 102 includes a binding unit 112, a shift tray 120, and the like. The binding unit 112 is an example of a binding means, and binds the ends of the printed matter P to form a bound portion. The shift tray 120 is an example of a stacking means, and the printed matter P with the bound portion formed thereon is stacked. Hereinafter, this embodiment will be described along with an example of conveying the printed matter.

[0020] The post-processing device 102 has, for example, an introduction path 1, a transport path 2, and a transport path 3. The introduction path 1 is a path that receives the printed matter P discharged from the image forming apparatus 101. The printed matter P is, for example, a sheet on which an image has been formed. The transport path 2 is a path along which the printed matter P is stacked on a discharge tray 10. The conveying path 3 is a path for stacking the printed matter P on the shift tray 120. In the conveying path 3, for example, the printed matter P is intermediately stacked, bound as a sheet bundle, and stacked on the shift tray 120.

[0021] An entrance roller 4 and an entrance sensor 5 are disposed on the introduction path 1. The entrance sensor 5 detects that the printed matter P has been carried into the post-processing device 102. Carrying the printed matter P into the post-processing device 102 may also be referred to as accepting, transporting, introducing, or the like.

[0022] A paper punching unit 20 is disposed downstream of the entrance rollers 4. The paper punching unit 20 performs, for example, a punching process (making holes) in the printed matter P. A transport roller 6 is disposed downstream of the paper punching unit 20. The printed matter P is transported to the transport path 2 or the transport path 3 via the transport rollers 6.

[0023] A branching claw 7 is disposed downstream of the transport rollers 6. The branching claw 7 switches whether the printed matter P transported from the introduction path 1 is transported to the transport path 2 or the transport path 3. The printed matter P transported to the transport path 2 is discharged to the discharge tray 10 by the discharge rollers 9.

[0024] The printed matter P transported to the transport path 3 is transported by transport rollers 8. The transport rollers 8 can be moved by a driving means, and can move, for example, in a direction perpendicular to the transport direction of the printed matter P. In FIG. 2, the driving means is not shown.

[0025] A paper discharge roller 113 and a paper discharge sensor 16 are arranged on the conveying path 3. The paper discharge roller 113 discharges the printed matter P onto a shift tray 120. The shift tray 120 is an example of a stacking means. The discharged printed matter P is loaded onto the shift tray 120. The loading of the printed matter P onto the shift tray 120 may also be referred to as being stacked or piled up. The paper discharge sensor 16 is used, for example, to count the number of loaded printed matters P.

[0026] For example, in sort mode, the conveying roller 8 moves a certain amount in a direction perpendicular to the conveying direction of the printed matter P. This causes the printed matter P to shift a certain amount in a direction perpendicular to the conveying direction. By shifting the printed matter P, the position of the printed matter P stacked on the shift tray 120 can be adjusted.

[0027] The discharge port to the shift tray 120 is provided with a discharge roller 113 and a discharge roller 12. The printed matter P is sandwiched between the discharge roller 113 and the discharge roller 12, and discharged to the shift tray 120 and stacked. The discharge roller 12 is a driven roller of the discharge roller 113. The discharge roller 12 can move between a closed state in which the printed matter P is sandwiched and can be discharged, and an open state in which the printed matter P is not sandwiched, as indicated by the double arrows in the figure, by the approaching and separating movement of the discharge guide. When the discharge roller 12 is located in the closed state, the printed matter P is sandwiched between the discharge roller 113 and the discharge roller 12, and discharged to the shift tray 120.

[0028] For the sake of explanation, it is described here that the printed materials P are clamped and discharged. When performing method 1 or method 2, a stack of bound printed materials P is clamped and discharged. Method 1 and method 2 may also be referred to as a staple mode, end binding mode, etc. When performing method 1 or method 2, a stack of bound printed materials P is loaded on the shift tray 120, but this embodiment does not exclude the case where a single sheet of printed materials P is loaded.

[0029] A filler 13 is provided near the top of the paper discharge port. The filler 13 is rotatably disposed, for example, at a position near the center of the printed materials P stacked on the shift tray 120. The tip of the filler 13 contacts the top surface of the printed materials P stacked on the shift tray 120. A top surface detection sensor that detects the height of the tip of the filler 13 is provided near the base of the filler 13. The top surface detection sensor is omitted in FIG. 2. The height of the stacked printed materials P can be detected by the top surface detection sensor.

[0030] As the number of printed materials P stacked on the shift tray 120 increases, the height of the printed materials P rises. When the height of the printed materials P stacked on the shift tray 120 exceeds a predetermined height, the control unit lowers the shift tray 120. The shift tray 120 can move up and down by a driving unit not shown in FIG. 2. The control unit controls each unit. Not shown in FIG. 2.

[0031] When the shift tray 120 descends and the height of the printed materials P stacked on the shift tray 120 returns to a predetermined height, the control unit stops the downward movement of the shift tray 120.

[0032] The discharge of the printed matter P and the up and down movement of the shift tray 120 are repeated, and when the shift tray 120 reaches a specified tray full height, a stop signal is sent from the post-processing device 102 to the image forming device 101. Upon receiving the stop signal, the image forming device 101 stops the image forming operation.

[0033] The conveying path 3 is provided with a binding unit 112, a staple tray 114, a tapping roller 11, a jogger fence 115, an end fence 119, and the like. The binding unit 112 forms a bound portion by binding the ends of the printed matter P. The process of binding the printed matter P is also referred to as a binding process. The binding unit 112 may be referred to as a stapler unit, a binding process mechanism, and the like.

[0034] The printed materials P are intermediately stacked on the staple tray 114. The printed materials P come into contact with an end fence 119. The jogger fence 115 aligns the positions of the printed materials P in the width direction.

[0035] The binding unit 112 can move back and forth in a direction perpendicular to the transport direction of the printed matter P by a guide 118. The direction in which the binding unit 112 moves is also referred to as the main scanning direction. In the example shown in the figure, the main scanning direction is a direction perpendicular to the plane of the paper in the figure, that is, the direction from the front side to the back side of the figure. The main scanning direction can also be said to be the width direction of the printed matter P.

[0036] An example of the transport of the printed matter P from the transport rollers 8 to the shift tray 120 will be described. The beating roller 11 can move as shown by the double-headed arrow in the figure, and discharges the printed matter P that has passed through the transport rollers 8 onto a staple tray 114. The movement of the beating roller 11 as shown by the double-headed arrow is also referred to as pendulum motion.

[0037] The jogger fence 115 advances and retreats in the main scanning direction (the direction perpendicular to the paper surface of the figure) to align the printed matter P on the staple tray 114. When performing method 1 or method 2, the printed matter P transported to the transport path 3 is discharged onto the staple tray 114 by the tapping roller 11, and the jogger fence 115 aligns the position in the width direction.

[0038] At this time, the striking roller 11 performs a pendulum motion and comes into contact with the upper surface of the printed matter P, switches the printed matter P back toward the binding unit 112, and brings the printed matter P into contact with the end fence 119. This process is performed on the multiple printed matters P, and the multiple printed matters P are intermediately stacked on the staple tray 114. As a result, the multiple printed matters P are aligned in the transport direction. In this way, the multiple printed matters P become a sheet bundle aligned in position on the staple tray 114.

[0039] When performing method 1 or method 2, the binding unit 112 performs a binding process on the aligned sheet stack. The binding unit 112 moves in the main scanning direction and forms a binding portion at an appropriate position on the end of the sheet stack. This binds the sheet stack. The stapled sheet stack is sandwiched between the sheet discharge roller 12 and the sheet discharge roller 113 and discharged to the shift tray 120, where it is stacked.

[0040] The binding unit 112 forms, for example, one binding portion at an end of a stack of printed materials P. In this case, it is possible to prevent an increase in processing time and obtain a stack of printed materials P that is easy to open without the printed materials P coming apart. Examples of the end of the stack of printed materials P include the vicinity of the upper right corner and the vicinity of the lower right corner of the printed materials P when viewed from above during stacking, as described below.

[0041] 3 is a block diagram showing an example of control of the image forming system 100. As shown in the figure, the image forming apparatus 101 and the post-processing apparatus 102 are connected so as to be able to communicate with each other.

[0042] The post-processing device 102 includes, for example, a control unit 103 , a detection unit 104 , and a driving unit 105 . The control unit 103 is a computer having, for example, a CPU, a storage unit, and a communication interface with the image forming apparatus 101. The storage unit of the control unit 103 is composed of, for example, a ROM, a RAM, and the like, and stores programs to be executed by the CPU, etc.

[0043] A detection unit 104 and a drive unit 105 are connected to the control unit 103, and the control unit 103 receives, for example, a detection result from the detection unit 104 and controls the detection unit 104, the drive unit 105, and the like.

[0044] The detection unit 104 may be called a detection means, and examples of the detection means include the entrance sensor 5, the paper discharge sensor 16, and the top surface detection sensor. Other examples of the detection means include a rear paper surface sensor 124 and a front paper surface sensor 125, which will be described later. The detection unit 104 sends, for example, information on the printed matter, information on the status of each means, and the like to the control unit 103.

[0045] The driving unit 105 may be a motor, etc. The driving unit 105 may be the above-mentioned driving means, etc., and may also be a means for moving the binding unit 112, etc.

[0046] For example, a CPU included in the control unit 103 operates the drive unit 105 in accordance with instructions sent from the image forming apparatus 101 and information sent from the detection unit 104 in accordance with a program stored in the storage unit. As a result, the post-processing device 102 performs, for example, paper alignment, edge binding, punching, and the like on the printed matter P conveyed from the image forming apparatus 101.

[0047] Fig. 4 is a schematic diagram of another main part of the post-processing device 102 of this example. Fig. 4 is a view from the same direction as Fig. 2, and shows a state as seen from a direction perpendicular to the conveying direction of the printed matter P. The above explanation also applies to Fig. 4. Here, a supplementary explanation of Fig. 2 is provided. Note that some of the means illustrated in Fig. 2 are omitted from Fig. 4.

[0048] As described above, the printed matter P carried in from the image forming apparatus 101 is intermediately stacked on the staple tray 114 and then bound by the binding unit 112. The bound printed matter P is discharged onto the shift tray 120 by the paper discharge rollers 113 and stacked on the shift tray.

[0049] 4 shows a state when the discharge rollers 12 are in a closed state, in which the discharge rollers 12 and the discharge rollers 113 sandwich and discharge the printed matter P. A discharge outlet (paper discharge outlet) formed by the discharge rollers 12 and the discharge rollers 113 is located above the stacking surface of the shift tray 120. The discharged printed matter P falls and is stacked on the shift tray 120.

[0050] The loading surface of the shift tray 120 may be horizontal or inclined as shown in the drawing. By inclining the loading surface of the shift tray 120, the discharged printed matter P approaches the direction of the paper discharge outlet due to its own weight, so that the positions of the printed matter P are easily aligned.

[0051] In the conveying path 3 shown in Fig. 4, a branching claw 17 and a reversing roller 19 are provided. When discharging in method 2, the printed matter P is reversed using the branching claw 17 and the reversing roller 19. For example, in method 1, the printed matter P is conveyed to the binding unit 112 with the printed side facing up, whereas in method 2, the printed side of the printed matter P is reversed using the branching claw 17 and the reversing roller 19, and the printed matter P is conveyed to the binding unit 112 with the printed side facing down. Note that the present invention is not limited to single-sided printing, and therefore "reversing the printed side of the printed matter P" may be rephrased as "reversing the front and back of the printed matter P", or the like.

[0052] 5 is a schematic diagram showing the state of the stacked paper bundle 121 stacked on the shift tray 120 when viewed from above. The stacked paper bundle 121 is a bundle of printed matter P formed by binding a plurality of printed matter P by the binding unit 112. The stacked paper bundle 121 is a bundle of printed matter P stacked by method 1, and is stacked on the shift tray 120 with one side (front side) of the printed matter P facing up. Stacking by method 1 is sometimes also referred to as face-up. The stacked paper bundle 121 is also sometimes referred to as the stacked paper bundle 121 (front side).

[0053] An example will be given for further explanation. For example, the printed matter P in the stacked paper bundle 121 has "A" printed on the surface thereof, and is stacked so that the upper side is the printed surface. The other printed matter P contained in the stacked paper bundle 121 also has "A" printed on it. In this example, a bound portion 117 is formed in the upper right corner of the stacked paper bundle 121 when viewed from above during stacking. By forming the bound portion 117, multiple printed matters P are bound together, and the printed matters P do not separate when the stacked paper bundle 121 is handled. The upper right corner where the bound portion 117 is formed corresponds to the end of the printed matter P.

[0054] The binding unit 112 can move in the main scanning direction by a guide 118. Therefore, the location where the bound portion 117 is formed can be appropriately selected.

[0055] 6 is a schematic diagram showing the state of the stacked paper stack 122 stacked on the shift tray 120 when viewed from above. The stacked paper stack 122 is a stack of printed matter P formed by binding a plurality of printed matter P by the binding unit 112. The stacked paper stack 122 is a stack of printed matter P stacked by method 2, and is stacked on the shift tray 120 with the other side (back side) of the printed matter P facing up. Stacking by method 2 is sometimes also referred to as face-down. The stacked paper stack 122 is also sometimes referred to as the stacked paper stack 122 (back side).

[0056] The stacked paper bundle 122 is formed by binding together a plurality of printed matter P, each having the same printed content printed on the lower side (reverse side) as the stacked paper bundle 121. In the example shown in the figure, when the stacked paper bundle 122 is viewed from above, the printed letter "A" is not visible, and therefore the letter "A" is shown by a dashed line in the figure.

[0057] In this example, when viewed from above during stacking, the bound portion 117 is formed in the lower right corner of the stacked paper stack 122. The lower right corner where the bound portion 117 is formed corresponds to the end of the printed matter P. When the stacked paper stack 122 in this example is turned over and upside down, the printed content and the position of the bound portion 117 become the same as those of the stacked paper stack 121.

[0058] 7 is a diagram showing a schematic example of the state of stacked paper bundles 121, 122 stacked on the shift tray 120 when viewed in the direction of the paper discharge outlet. The stacked paper bundles 121, 122 are sandwiched between the paper discharge roller 12 and the paper discharge roller 113 and discharged, and are stacked on the shift tray 120. The stacked paper bundles 121, 122, and printed materials stacked on the shift tray 120 may be collectively referred to as stacks, stacked bundles, etc.

[0059] In the figure, the stacked paper bundles 121 and 122 appear to have the bound portion 117 formed for one printed matter, but the stacked paper bundles 121 and 122 have the bound portion 117 formed for multiple printed matters.

[0060] In the illustrated example, the stacked paper bundles 121 and 122 are alternately stacked one copy at a time. This distributes the bound parts 117 of the stacked paper bundles 121 and the bound parts 117 of the stacked paper bundles 122 to the left and right. This prevents the height of the stacked objects from being biased in one direction, and prevents the stacked state of the stacked objects from becoming distorted.

[0061] Fig. 8 is a schematic diagram showing the state in which stacked paper bundles 121 and 122 are removed from shift tray 120 in the example shown in Fig. 7. In Fig. 8(A), "A" (dashed line) is shown only on the top stacked paper bundle 122. As shown in the figure, stacked paper bundles 121 and stacked paper bundles 122 are stacked alternately, one copy at a time. Therefore, if a user wants to align the front and back of the stacked items, the user needs to turn them over one by one to align them.

[0062] For the sake of explanation, the cross-sectional view in Fig. 8(B) shows the print surface 126 in a schematic manner. As shown in the figure, the print surface 126 is on the lower side in the stacked paper bundle 122, and the print surface is on the upper side in the stacked paper bundle 121. The user can turn the stacked items over one by one to align them so that the print surfaces are the same.

[0063] In the conventional technology, as shown in Figs. 7 and 8, when it is desired to align the front and back of the stacked objects, the user must turn the stacked objects over one by one to align them, which is time-consuming. In this embodiment, therefore, multiple copies of the stacked paper bundle 121 are continuously stacked using method 1 or method 2, and the user can set the number of copies (number of copies X) to be continuously stacked. The number of copies X can also be said to be the number of copies at which to switch between method 1 and method 2. This makes it possible to prevent the stacked objects from becoming locally high, and also reduces the time and effort required by the user to align the front and back of the stacked objects. Furthermore, in this embodiment, the user can freely decide the number of copies of the stacked printed materials to be continuously stacked, improving user convenience.

[0064] Fig. 9 is a diagram showing a schematic state of an example of a stack obtained by this embodiment, and is a diagram similar to Fig. 7. As shown in the figure, a plurality of stacked paper bundles 121 (front side) are stacked, and a plurality of stacked paper bundles 122 (back side) are stacked on top of the stacked paper bundles 121 (front side). In the example shown in the figure, the number of copies X is 4 copies.

[0065] As shown in the figure, the positions of the binding portions 117 in the stack are dispersed, so that it is possible to prevent the height of the stack from becoming locally high. This makes it possible to prevent the stack capacity from decreasing to the point where the stack becomes an obstacle and new sheet bundles cannot be discharged. This makes it possible to prevent a decrease in the stack capacity of the shift tray 120. In addition, since the height of the stack is unlikely to become locally high, the stacked state of the stack is unlikely to become distorted. In addition, since multiple copies of stacked paper bundles 121 and stacked paper bundles 122 are each stacked continuously, it becomes easy for the user to align the front and back orientations of the stacked objects.

[0066] In this embodiment, it is possible to select between method 1, in which a stack of printed materials P is loaded on the loading means with one side of the printed materials facing up, and method 2, in which a stack of printed materials is loaded on the loading means with the other side of the printed materials facing up. Methods 1 and 2 differ in the position of the binding part when loaded on the loading means. In addition, the user can set the number of copies (number of copies X) of a stack of printed materials to be continuously loaded in method 1 or method 2. The control unit 103 switches between method 1 and method 2 for each number of copies X and controls the stacking of printed materials.

[0067] The method for setting the number of copies X can be selected as appropriate. For example, the number of copies X may be included in the print instruction from the user, or the user may input the number of copies X after the image forming system 100 receives the print instruction. The method for the user to input the number of copies X can be selected as appropriate, and an example of this is a method in which the image forming system 100 has a display unit 106 and the user operates the display unit 106 to input the number of copies X. An example of the display unit 106 is a display panel (which may be referred to as a display, etc.) provided in the image forming apparatus. In addition to the above, the number of copies X may be set in advance before issuing a print instruction.

[0068] Fig. 10 is an example of a flowchart in this embodiment. In this example, the stacking of stacked paper bundles 121 and stacked paper bundles 122 can be switched based on X copies, which is a fixed number of copies set by the user. This makes it possible to obtain, for example, the stack shown in Fig. 9. In the example of the flowchart shown in Fig. 10, a processing example of the image forming system 100 is described, including the processing of the image forming apparatus 101 and the post-processing apparatus 102. Also, in the flowchart of this example, the processing also includes a case where the user performs an action.

[0069] In this example, switching between Method 1 and Method 2 for stacking may be referred to as a reversing process and a binding position changing process.

[0070] The image forming system 100 receives a print instruction from a user (S1). Next, the control unit of the post-processing device 102 determines whether or not to perform binding processing (S2). The binding processing is a process performed by the post-processing device 102. If the binding processing is not performed, that is, if the answer is NO in S2, the process leaves the flow of this example and performs another process. An example of the other process is a process of discharging the printed matter P to the paper discharge tray 10. In this case, for example, the post-processing device 102 transports the printed matter P via the transport path 2 in FIG. 2 and stacks the printed matter P on the paper discharge tray 10.

[0071] When binding processing is performed (YES in S2), the control unit 103 of the post-processing device 102 determines (S3) whether more than two copies are to be printed. Two copies here refers to the total number of copies of the stack of printed materials P. If the total number of copies of the stack of printed materials P in the print instruction exceeds two copies, the determination in S3 is YES.

[0072] If more than two copies are not to be printed, that is, if S3 is NO, the remaining number of copies (assumed to be one copy here) is discharged to the shift tray 120 as normal (S9). In this case, the reversal process and the binding position change process are not performed. For example, method 1 is performed, and the sheets are stacked on the shift tray 120 in the state of the stacked paper stack 121. However, the sheets may also be discharged using method 2.

[0073] If more than two copies are to be printed, that is, if S3 is YES, a screen prompting the user to input the number of copies X is output to the display unit 106 (S4). For example, a screen prompting the user to input the number of copies to be switched between face-up (front) and face-down (back) is output on the operation screen of the display unit 106.

[0074] The user inputs an arbitrary number of copies X for which the front and back are to be switched (S5). After receiving the number of copies X from the user, the image forming system 100 starts printing (S6). Specifically, the image forming apparatus 101 starts forming an image. As described above, the printed matter P on which the image is formed by the image forming apparatus 101 is discharged from the image forming apparatus 101 and conveyed to the post-processing apparatus 102.

[0075] The control unit 103 determines whether the number of remaining copies to be printed exceeds the number of copies X (S7). If the number of remaining copies to be printed does not exceed the number of copies X (NO in S7), the remaining copies are discharged to the shift tray 120 as usual (S9). Although not particularly limited, for example, if the stack of printed materials is 10 copies and the number of copies X input by the user is 20 copies, 10 copies are discharged using method 1 without switching between method 1 and method 2. Note that if the number of remaining copies to be printed is the same as the number of copies X, it is preferable to include this in the case of YES in S7.

[0076] If the number of remaining copies to be printed exceeds the number of copies X (YES in S7), X copies are output (S8) while switching between method 1 and method 2. Since it is necessary to turn the printed matter P over when using method 2, the first time it is output using method 1. For the second or subsequent processing, the method used for output is different from the method used for the previous output. For example, the first time X copies are output using method 1, the second time X copies are output using method 2, and the third time X copies are output using method 1.

[0077] After S8, the process returns to S7 and is repeated. By repeating the processes of S7 and S8, stacks of printed matter can be stacked by switching between method 1 and method 2 for each number of copies X. In this way, stacks can be stacked, for example, as shown in stacked paper bundles 121 and 122 in FIG.

[0078] The process of reversing the front and back and the process of changing the binding position in S8 in this example will be further explained with reference to Fig. 4. When method 2 is performed, for example, the following is performed. The printed matter P transported to the transport path 3 is reversed by the reversing roller 19. The printed matter P with the front and back reversed is stacked on the staple tray 114, and when multiple printed matters P are stacked, the binding unit 112 performs the binding process. The binding unit 112 forms a binding portion 117, and the assembled stack of sheets is discharged to the shift tray 120. As a result, the stack of sheets 122 (back) is stacked.

[0079] For example, when X copies are discharged onto the shift tray 120, a predetermined counter is reset and counts again until the next X copies are discharged onto the shift tray 120.

[0080] Second Embodiment Next, other embodiments of the present invention will be described. In this embodiment, processing is performed taking into consideration the number of printed sheets P per copy. In this embodiment, the control of switching between the method 1 and the method 2 for each copy number X and stacking the stack of printed sheets is performed when the number of sheets to be bound together in the plurality of printed sheets is equal to or less than a threshold number Y. This reduces the amount of work required for the user to operate the stack while reducing unevenness in the height of the stack.

[0081] Hereinafter, the number of sheets to be bound together of multiple printed materials is also referred to as the number of sheets of printed materials per copy, the number of sheets of printed materials P bound together per copy, the number of sheets of printed materials included in a bundle of printed materials, etc. In addition, the number of sheets to be bound together of multiple printed materials may also be referred to as the number of printed materials per copy.

[0082] 11 is a diagram for explaining an example of a load in this embodiment, as viewed from the same direction as in FIG. 7, etc. In the illustrated example, a stack of paper sheets 123 is shown loaded on the shift tray 120.

[0083] The stacked paper bundle 123 is a stacked paper bundle that has been stapled when there are many printed matter P per copy. The difference between the stacked paper bundle 123 and the stacked paper bundle 121 (front) is, specifically, whether the number of stapled sheets per copy is greater than the number of stapled sheets (number of sheets Y) at which the influence of the stapler 117 becomes greater. The stacked paper bundle 123 has a greater number of stapled sheets per copy than number of sheets Y, while the stacked paper bundle 121 (front) and the stacked paper bundle 122 (back) have a lesser number of stapled sheets per copy than number of sheets Y.

[0084] The smaller the number of stapled sheets per set, the greater the effect of the stapled portion 117. Since the stacked paper bundles 121 have fewer sheets of printed matter P per set than the stacked paper bundles 123, the stacked paper bundles 121 are prone to collapse due to overlapping even if the number of sets is smaller than that of the stacked paper bundles 123.

[0085] On the other hand, since the number of printed matter P per copy is large in the stacked paper stack 123, the influence of the binding portion 117 is smaller than in the stacked paper stack 121. Therefore, in the stacked paper stack 123, the process of turning over the front and back and the process of changing the position of the binding portion may be less than in the stacked paper stack 121.

[0086] For example, when comparing the case of 2-sheet binding with the case of 50-sheet binding, the number of overlapping sheets of the bound portion 117 when stacked to the same height is greater in the case of 2-sheet binding. Therefore, in the case of 2-sheet binding, the bias in the stacking height between the rear side and the front side is greater than in the case of 50-sheet binding. In the case of 50-sheet binding, the influence of the bound portion 117 is relatively smaller than in the case of a smaller number of bound sheets, such as 2-sheet binding. For this reason, in this embodiment, the number of printed matter P per copy is taken into consideration.

[0087] As described above, the number of bound sheets at which the influence of the bound portion 117 becomes greater depending on the number of bound sheets of printed matter P per set is set to number Y. When the number of bound sheets of printed matter P per set is equal to or less than number Y, the process of turning over the sheets and the process of changing the position of the bound portion (switching between method 1 and method 2) are automatically performed. When the number of bound sheets of printed matter P per set is greater than number Y, the process of turning over the sheets and the process of changing the position of the bound portion are not performed. In this way, it is possible to further prevent the stacked items stacked on the shift tray 120 from collapsing.

[0088] The number of printed matter P per copy is included in, for example, a print instruction from a user. The number of sheets Y is stored in advance in the image forming system 100 before, for example, receiving a print instruction, and may be set by the user or by someone other than the user. Setting the number of sheets Y in advance can save the user the trouble of performing an input operation. The number of sheets Y can be set to any value, and is set, for example, taking into consideration the type of recording medium, the type of binding unit 117, etc.

[0089] Fig. 12 is an example of a flowchart in this embodiment. In this example, the number of bound sheets of printed matter P per set is compared with the number of sheets Y, and if it exceeds the number of sheets Y, the stack of stacked paper bundles 121 and 122 is not switched. If the number of bound sheets of printed matter P per set falls below the number of sheets Y, the stack of stacked paper bundles 121 and 122 is switched according to the number of sheets X set by the user, as in the flowchart in Fig. 10 above.

[0090] In the flowchart shown in Fig. 12, the same processes as those in the flowchart in Fig. 10 are denoted by the same reference numerals. In this example, the process of making the determination in S10 is mainly different from the process in the flowchart in Fig. 10.

[0091] In this example, steps S1 to S3 and S9 are the same as those in the flowchart of FIG. In this example, a judgment is made in S10. In S10, it is judged whether the number of sheets to be bound in one set of printed matter P exceeds the number of sheets Y. If the number of sheets to be bound in one set exceeds the number of sheets Y, that is, if the judgment is YES in S10, the paper is discharged as usual without performing the process of turning over the paper and changing the binding position (S9). In this case, the paper is discharged using method 1.

[0092] If the number of sheets to be bound per set is equal to or less than Y, that is, if the answer is NO in S10, the process of S4 to S8 is performed in the same manner as in the flowchart of Fig. 10. In this example, the same process as in the above embodiment is performed, so a description thereof will be omitted here.

[0093] In this way, the stack of printed materials can be loaded taking into account the number of printed materials P per copy, and the need to turn the sheets over and change the binding position can be determined automatically without user operation.

[0094] (Third embodiment) Next, other embodiments of the present invention will be described. In this embodiment, two paper surface sensors are used, and processing is performed taking into account the detection by the paper surface sensors.

[0095] The post-processing device of this embodiment includes a first detection means for detecting a height of the stack of printed materials in the first area and a second detection means for detecting a height of the stack of printed materials in the second area, when an area in the stacking means where the bound portion of the stack of printed materials is located when stacked in Method 1 is defined as a first area and an area in which the bound portion of the stack of printed materials is located when stacked in Method 2 is defined as a second area. Furthermore, when only one of the first detection means or the second detection means detects that the height of the stack of printed materials exceeds a predetermined height, the control unit performs control to switch between Method 1 and Method 2 to stack the stack of printed materials.

[0096] According to this embodiment, by monitoring the detection state of the first detection means (e.g., the rear side paper surface sensor) and the second detection means (e.g., the front side paper surface sensor), it is possible to automatically determine whether to perform the front / back inversion process and the binding position change process. This saves the user the trouble of monitoring and prevents the load capacity of the loading means from decreasing. In addition, the loading state of the loaded items is less likely to become distorted.

[0097] 13 is a diagram for explaining an example of the post-processing device 102 and a stack of items according to the present embodiment. The diagram is seen from the same direction as in FIG. 7. In the illustrated example, a stack of paper sheets 121 (front side) is stacked on the shift tray 120.

[0098] The post-processing device 102 of this embodiment has a rear-side paper surface sensor 124 and a front-side paper surface sensor 125. The rear-side paper surface sensor 124 and the front-side paper surface sensor 125 are provided between the shift tray 120 and the paper discharge rollers 113.

[0099] In the shift tray 120, the area where the stapled portion 117 of the stacked paper stack 121 is located when stacked in method 1 is defined as the first area, and the area where the stapled portion 117 of the stacked paper stack 122 is located when stacked in method 2 is defined as the second area. In this example, the first area is the left side of the drawing, and this area is referred to as the back side. The second area is the right side of the drawing, and this area is referred to as the front side. The back side paper surface sensor 124 detects the height of the loaded items in the first area (back side). The front side paper surface sensor 125 detects the height of the loaded items in the second area (front side).

[0100] 13 shows a state where the rear paper surface sensor 124 detects the stacked objects, and the front paper surface sensor 125 does not detect the stacked objects. If the discharge is continued in this state, the height of the stacked objects will become locally high, and the discharge of the sheet stack will be hindered. Therefore, in this embodiment, when only one of the rear paper surface sensor 124 and the front paper surface sensor 125 detects a predetermined height, the front and back reversal process and the binding position change process are performed.

[0101] Fig. 14 is a diagram for explaining an example of a stack obtained by the post-processing device 102 of this embodiment. Fig. 14 is an example of a case where a sheet stack is further stacked on the state of Fig. 13. In Fig. 13, only the rear paper surface sensor 124 detects a predetermined height of the stack, so that the subsequent paper discharge involves a process of reversing the front and back and a process of changing the binding position. Therefore, the stacked paper stack 122 (rear) is stacked on the shift tray 120, and the position of the binding portion 117 is dispersed as shown in Fig. 14.

[0102] In this way, when only one of the rear paper surface sensor 124 and the front paper surface sensor 125 detects that the stack has reached a predetermined height, the process of reversing the front and back and the process of changing the binding position are automatically performed. This makes it possible to prevent the stack from decreasing to the point where the stack becomes an obstacle and a new sheet bundle cannot be discharged. This makes it possible to prevent the stack capacity of the shift tray 120 from decreasing. In addition, the stack state of the stack is less likely to be disturbed.

[0103] 15 is an example of a flowchart in this embodiment. In this example, when the paper is discharged and either the rear paper surface sensor 124 or the front paper surface sensor is turned ON, the paper is turned over and the binding position is changed.

[0104] The ON state of the sensor means that the load has reached a predetermined height at the location where the sensor is detecting. The OFF state of the sensor means that the sensor is not detecting the load. The OFF state of the sensor means that after the sensor detected the load, the height of the load has decreased and the sensor is no longer detecting the load.

[0105] The image forming system 100 receives a print instruction from a user (S21). Next, the control unit of the post-processing device 102 determines whether or not to perform binding processing (S22). The binding processing is a process performed by the post-processing device 102. If the binding processing is not performed, that is, if the answer is NO in S2, the process leaves the flow of this example and performs another process. An example of the other process is a process of discharging the printed matter P to the paper discharge tray 10. In this case, for example, the post-processing device 102 transports the printed matter P via the transport path 2 in FIG. 2 and stacks the printed matter P on the paper discharge tray 10.

[0106] When binding processing is performed (YES in S22), the control unit of the post-processing device 102 determines (S23) whether more than two copies are to be printed. Here, two copies refers to the total number of copies of the stack of printed materials P. If the total number of copies of the stack of printed materials P in the print instruction exceeds two copies, the determination in S23 is YES.

[0107] If more than two copies are not to be printed, that is, if the answer is NO in S23, the remaining copies are normally discharged to the shift tray 120 (S35). In this case, the reversal process and the binding position change process are not performed. For example, the paper is discharged by method 1, and the paper is stacked on the shift tray 120 in the state of the stacked paper bundle 121. However, the paper may be discharged by method 2.

[0108] If more than two copies are to be printed, that is, if S23 is YES, a screen prompting input of the number of copies X is output to the display unit 106 (S24). For example, a screen prompting input of how many copies to switch between face-up (front) and face-down (back) is output on the operation screen of the display unit 106.

[0109] The user inputs an arbitrary number of copies X for which the front and back are to be switched (S25). After receiving the number of copies X from the user, the image forming system 100 starts printing (S26). Specifically, the image forming apparatus 101 starts forming an image. As described above, the printed matter P on which the image is formed by the image forming apparatus 101 is discharged from the image forming apparatus 101 and conveyed to the post-processing apparatus 102.

[0110] Next, the control unit 103 performs a determination of the paper surface sensor (S27). If the determination in S27 is NO, i.e., if neither the rear paper surface sensor 124 nor the front paper surface sensor is ON, the control unit 103 determines whether the number of remaining copies to be printed exceeds the number of copies X (S28). If the number of remaining copies to be printed does not exceed the number of copies X (NO in S28), the remaining copies are ejected onto the shift tray 120 as usual and the process ends (S30).

[0111] If the number of remaining copies to be printed exceeds the number of copies X (YES in S28), X copies are discharged (S29) while switching between method 1 and method 2. After S29, the process returns to S27 and is repeated.

[0112] If the determination in S27 is YES, that is, if either the rear paper surface sensor 124 or the front paper surface sensor is ON, the method switches between Method 1 and Method 2 and ejects X portions of paper (S31). Next, it is determined whether the paper surface sensor that was ON has turned OFF (S32). This is because stacking is performed after the paper surface sensor turns ON, and it is detected that the height of the stack has become lower.

[0113] If the determination in S32 is YES, that is, if the paper surface sensor that was in the ON state becomes in the OFF state, the process returns to the determination process in S27.

[0114] If the determination in S32 is NO, that is, if the paper surface sensor that was in the ON state remains in the ON state, the paper is discharged and stacked without performing the inversion process or the binding position change process (S33). In other words, the paper is discharged normally without switching between method 1 and method 2.

[0115] Next, it is determined whether there are any remaining copies to be printed (S34). If there are no remaining copies to be printed, that is, if the answer is NO in S34, the process ends. If there are remaining copies to be printed (if YES), the process returns to the determination process of S32.

[0116] By carrying out such processing, a load such as that shown in FIG. 14 can be obtained.

[0117] For example, aspects of the present invention are as follows. <1> A binding means for binding a plurality of printed materials to form a bound portion and form a bundle of the printed materials; A stacking means for stacking the stack of printed matter; A post-processing device comprising: A method 1 in which the stack of printed materials is loaded on the loading means with one side of the printed materials facing up, and a method 2 in which the stack of printed materials is loaded on the loading means with the other side of the printed materials facing up can be selected, and the method 1 and the method 2 have different positions of the binding portion when the printed materials are loaded on the loading means, The number of copies of the bundle of printed materials to be continuously stacked in the method 1 or the method 2 can be set by a user, and the number of copies set by the user is designated as number of copies X; The control unit switches between the method 1 and the method 2 for each number of copies X and controls stacking of the bundle of printed materials. A post-processing device comprising: <2> The control of switching between the method 1 and the method 2 for each copy number X and stacking the bundle of printed materials is performed when the number of sheets to be bound together of the plurality of printed materials is equal to or less than a threshold number Y. Characterized by <1> The post-processing device according to claim 1 . <3> In the loading means, when an area where the bound portion of the stack of printed materials is located when the stack is loaded in the first method is defined as a first area, and an area where the bound portion of the stack of printed materials is located when the stack is loaded in the second method is defined as a second area, a first detection means is provided for detecting a height of the stack of printed materials in the first area, and a second detection means is provided for detecting a height of the stack of printed materials in the second area, When only one of the first detection means or the second detection means detects that the height of the stack of printed materials exceeds a predetermined height, the control unit switches between the method 1 and the method 2 to stack the stack of printed materials. Characterized by <1> The post-processing device according to claim 1 . <4> <1> from <3> The post-processing device according to any one of 1. An image forming system comprising: <5> After receiving a print instruction from the user, the number of copies X is input by the user. Characterized by <4> 2. The image forming system according to claim 1 . <6> A display unit is provided, The display unit displays a message prompting the user to input the number of copies X. Characterized by <4> or <5> 2. The image forming system according to claim 1 . [Explanation of symbols]

[0118] 1. Introduction route 2, 3 Transport route 4 Entrance roller 5 Inlet Sensor 6, 8 Conveyor rollers 7 Branch Claw 9 Discharge roller 10 Output tray 11 Beating Roller 12 Paper ejection roller 13. Filler 16 Paper ejection sensor 19 Reversing roller 100 Image forming system 101 Image forming device 102 Aftertreatment device 103 Control section 104 Detection unit 105 Drive unit 112 Binding unit 113 Paper ejection roller 114 Staple Tray 115 Jogger Fence 117 Binding 118 Guide 119 End Fence 120 Shift Tray 121~123 Paper stack 124 Back side paper surface sensor 125 Front paper sensor [Prior art documents] [Patent documents]

[0119] [Patent Document 1] JP 2000-59552 A

Claims

1. A binding means for binding a plurality of printed materials to form a bound portion and form a bundle of the printed materials; A stacking means for stacking the stack of printed matter; A post-processing device comprising: A method 1 in which the stack of printed materials is loaded on the loading means with one side of the printed materials facing up, and a method 2 in which the stack of printed materials is loaded on the loading means with the other side of the printed materials facing up can be selected, and the method 1 and the method 2 have different positions of the binding portion when the printed materials are loaded on the loading means, The number of copies of the bundle of printed materials to be continuously stacked in the method 1 or the method 2 can be set by a user, and the number of copies set by the user is designated as the number of copies X; The control unit switches between the method 1 and the method 2 for each number of copies X and controls stacking of the bundle of printed materials. A post-processing device comprising:

2. The control of switching between the method 1 and the method 2 for each number of copies X and stacking the bundle of printed materials is performed when the number of sheets to be bound together of the plurality of printed materials is equal to or less than a threshold number Y. The post-processing device according to claim 1 .

3. In the loading means, when an area in which the bound portion of the stack of printed materials is located when the stack is loaded in the first method is defined as a first area, and an area in which the bound portion of the stack of printed materials is located when the stack is loaded in the second method is defined as a second area, a first detection means is provided for detecting a height of the stack of printed materials in the first area, and a second detection means is provided for detecting a height of the stack of printed materials in the second area, The control unit switches between the method 1 and the method 2 to stack the stack of printed materials when only one of the first detection unit and the second detection unit detects that the height of the stack of printed materials exceeds a predetermined height. The post-processing device according to claim 1 .

4. A post-processing device according to any one of claims 1 to 3 and an image forming device, The post-processing device receives the printed matter from the image forming device.

1. An image forming system comprising:

5. After receiving a print instruction from the user, the number of copies X is input by the user.

5. The image forming system according to claim 4.

6. A display unit is provided, The display unit displays a message prompting the user to input the number of copies X.

5. The image forming system according to claim 4.

Images