Image forming apparatus, post-processing position adjustment method, and recording medium

Abstract

An image forming apparatus includes a post-processing device that folds a paper on which an image is formed, a document reading section that reads a document, a reading control section (53) that acquires image data output by the document reading section reading an area including an outline of the document with a fold caused by the post-processing device, and a relative position determination section (59) that determines a relative position of the outline of the document and the fold based on the image data.

Description

Technical Field

[0001] This invention relates to an image forming apparatus, a post-processing position adjustment method, and a computer-readable recording medium containing a post-processing position adjustment program. In particular, it relates to an image forming apparatus having the function of processing paper, a post-processing position adjustment method executed by the image forming apparatus, and a computer-readable recording medium containing a post-processing position adjustment program that causes a computer controlling the image forming apparatus to execute the post-processing position adjustment method. Background Technology

[0002] Post-processing apparatuses are known for processing paper with images formed by multifunction printers such as MFPs (Multi-Function Peripherals). Paper processing includes folding the paper. In this post-processing apparatus, the position of the folded paper needs to be adjusted. Japanese Patent Application Publication No. 2016-158113 discloses an image reading device comprising: a transparent plate on which an original document can be placed; a first light irradiation unit located below the transparent plate and in a region divided on one side by a first plane perpendicular to the image reading surface of the original document, irradiating light from an inclined direction onto the image reading position of the original document; a second light irradiation unit disposed separately from the first light irradiation unit, located below the transparent plate and in a region divided on the other side by the first plane, irradiating light from an inclined direction onto the image reading position of the original document; and a light receiving unit capable of receiving light from both the first and second light irradiation units in both directions. The original document is irradiated with reflected light; a first image information acquisition unit receives reflected light from both the first and second light irradiation units and irradiates the original document to acquire first image information of the original document; a second image information acquisition unit receives reflected light from the first light irradiation unit and irradiates the original document to acquire second image information of the original document; a third image information acquisition unit receives reflected light from the second light irradiation unit and irradiates the original document to acquire third image information of the original document; and a crease information exporting unit exports crease information of the original document based on the acquired first, second, and third image information.

[0003] In the image reading device described in Japanese Patent Application Publication No. 2016-158113, although the position of creases in the image information obtained by reading the original document can be detected, the position of creases in the original document cannot be accurately detected if the original document is not correctly positioned on the transparent plate. When the original document with creases is unfolded, the crease area is not flat. Therefore, when the unfolded original document is placed on the transparent plate, there is a situation where the relative position of the paper with respect to the transparent plate is offset, making it difficult to accurately position the original document on the transparent plate.

[0004] Patent Document 1: Japanese Patent Application Publication No. 2016-158113 Summary of the Invention

[0005] This invention was made to solve the above-mentioned problems. One of the purposes of this invention is to provide an image forming apparatus that can accurately detect the position of creases in the original document.

[0006] Another objective of this invention is to provide a post-processing position adjustment method that can accurately detect the position of creases in the original document.

[0007] Another objective of this invention is to provide a post-processing position adjustment procedure capable of accurately detecting the position of creases in the original document.

[0008] To achieve the above objectives, according to one aspect of the invention, an image forming apparatus includes: a post-processing unit for folding a piece of paper with an image formed thereon; a manuscript reading unit for reading a manuscript; a reading control unit for acquiring image data output by the manuscript reading unit from a region containing the outline of the manuscript folded by the post-processing unit with creases; and a relative position determination unit for determining the relative position of the outline of the manuscript and the creases based on the image data.

[0009] According to this aspect, the relative position of the original's outline and the crease is determined based on image data obtained by reading an area containing the outline of an original document folded by a post-processing device and bearing creases. Therefore, by determining the crease position based on the original's outline in the image data, the crease position can be determined regardless of the original's current position at the time of reading. As a result, an image forming apparatus capable of accurately detecting the position of creases within the original document can be provided.

[0010] The preferred original document reading unit comprises: a first illumination unit that illuminates the original document with light at a first incident angle; a second illumination unit that illuminates the original document with light at a second incident angle different from the first incident angle; and a light receiving unit that receives the light illuminated by the first illumination unit and the second illumination unit. The relative position determination unit extracts the creases and contours of the original document based on the first image data output by the light receiving unit receiving the light illuminated by the first illumination unit and the second image data output by the light receiving unit receiving the light illuminated by the second illumination unit.

[0011] According to this aspect, since the first incident angle and the second incident angle are different, it is possible to detect areas where the pixel values ​​in the first image data and the second image data differ in the region surrounding the crease of the original document. As a result, it is possible to accurately detect the crease of the original document in the image data.

[0012] Preferably, it also includes a determination unit that determines the amount of correction for setting values ​​set in the post-processing device based on the relative position of the outline and creases of the original artwork.

[0013] Based on this, the amount of correction can be easily determined according to the offset of the creases in the original manuscript.

[0014] Preferably, the notification unit also has a notification correction function.

[0015] Based on this, the user is notified of the correction amount, so the user can confirm the correction amount.

[0016] Preferably, it also includes a correction unit that corrects the set value set in the post-processing device by correcting the correction amount.

[0017] Based on this, the settings set in the post-processing device can be automatically corrected.

[0018] The preferred unit for correction is length.

[0019] Based on this, users can grasp the amount of correction by length, so they can measure the actual offset to confirm the amount of correction.

[0020] The preferred unit for correction is ratio.

[0021] Based on this, it is possible to notify the amount of correction for multiple paper dimensions using a ratio that serves as the same reference.

[0022] Preferably, it also includes: an image forming unit for forming an image on paper and outputting an original; and a relative orientation acquisition unit for acquiring a relative orientation representing the relative orientation of the image with respect to the original, based on the relative orientation of the paper and the image when the image forming unit outputs the original.

[0023] Based on this, the relative orientation of the original and the image can be obtained. Therefore, the accuracy of the correction amount can be improved.

[0024] According to other aspects of the invention, the post-processing position adjustment method is a post-processing position adjustment method performed by an image forming apparatus, the image forming apparatus having a post-processing device for folding paper to form an image, and the image forming apparatus further having an original document reading unit for reading the original document, the post-processing position adjustment method comprising: a reading control step of acquiring image data output by the original document reading unit for reading an area containing the outline of the original document folded by the post-processing device with creases; and a relative position determination step of determining the relative position of the outline of the original document and the creases based on the image data.

[0025] Based on this, a post-processing position adjustment method can be provided that can accurately detect the position of creases in the original document.

[0026] According to other aspects of the invention, a computer-readable recording medium recording a post-processing position adjustment program is recorded, which is executed by a computer controlling an image forming apparatus. The image forming apparatus includes a post-processing device for folding paper to form an image, and also includes a document reading unit for reading the original document. The computer-readable recording medium records the post-processing position adjustment program, which causes the computer to execute: a reading control step, acquiring image data output by the document reading unit that includes the outline of the original document folded by the post-processing device with creases; and a relative position determination step, determining the relative position of the outline of the original document and the creases based on the image data.

[0027] In this respect, it is possible to provide a computer-readable recording medium that records a post-processing position adjustment program capable of accurately detecting the position of creases on the original document within the original document. Attached Figure Description

[0028] Figure 1 This is a front view of an image forming apparatus according to one embodiment of the present invention.

[0029] Figure 2 This is a schematic cross-sectional view showing an example of the internal structure of the main body of an MFP.

[0030] Figure 3 This is a diagram showing the internal structure of the post-processing unit.

[0031] Figure 4 This is the first diagram used to illustrate the three-fold processing based on the second mechanism.

[0032] Figure 5 This is the second diagram used to illustrate the three-fold processing based on the second mechanism.

[0033] Figure 6 This is the third diagram used to illustrate the three-fold processing based on the second mechanism.

[0034] Figure 7 This is the first diagram used to illustrate the Z-fold processing based on the first mechanism.

[0035] Figure 8 This is the second diagram used to illustrate the Z-fold processing based on the first mechanism.

[0036] Figure 9 It is a block diagram that shows the general hardware configuration of an MFP.

[0037] Figure 10 This is a block diagram illustrating an example of the functions that an MFP possesses, similar to those of a CPU.

[0038] Figure 11 This is a diagram representing an example of synthetic data.

[0039] Figure 12 This is a graph representing an example of differenced data.

[0040] Figure 13 This is an example of a screen displaying a correction amount adjustment.

[0041] Figure 14 This is a flowchart illustrating an example of the image formation process.

[0042] Figure 15 This is a flowchart illustrating an example of the output image reading and processing procedure.

[0043] Figure 16 This is a flowchart illustrating an example of the post-processing position adjustment process.

[0044] Figure 17 This is an example diagram showing the adjustment of the correction amount in a variant example. Detailed Implementation

[0045] Hereinafter, taking an MFP (Multi-Function Peripheral) as an example, the image forming apparatus according to an embodiment of the present invention will be described with reference to the accompanying drawings. In the following description, the same reference numerals are used for the same parts. Their names and functions are also the same. Therefore, detailed descriptions of them will not be repeated.

[0046] Figure 1 This is a front view of an MFP according to one embodiment of the present invention. (Refer to...) Figure 1 The MFP100 functions as an image forming apparatus, comprising a main body 101 and a post-processing unit 200. The main body 101 includes: a document reading unit 130 for reading originals; an automatic document transport device 120 for transporting originals to the document reading unit 130; an image forming unit 140 for forming an image on a recording medium based on image data output from the originals read by the document reading unit 130; a paper supply unit 150 for supplying the recording medium to the image forming unit 140; and an operation panel 160 serving as a user interface. The main body 101 can form images on any of several types of recording media that are the objects of image formation. Besides paper, recording media include OHP (Overhead Projector) sheets, cloth, etc. In the following description, unless otherwise specified, the case where the recording medium is paper will be used as an example.

[0047] The post-processing unit 200 is supplied with paper bearing an image from the main body 101. The post-processing unit 200 includes a folding mechanism for processing the paper. The folding mechanism performs the process of folding a bundle of one or more sheets of paper at a predetermined position. The post-processing unit 200 performs three folding processes depending on the position and direction of the folds. The three folding processes include: a center fold (folding the paper in the center), a triple fold (folding the paper by making valley folds along the two folds after dividing the paper into thirds), and a Z-fold (folding the paper by making a mountain fold on one side and a valley fold on the other side along the two folds after dividing the paper into thirds). Additionally, the post-processing unit 200 includes a binding mechanism for stapled into the bundle of multiple sheets of paper. Furthermore, the post-processing unit 200 may also include a sorting mechanism for sorting and arranging the paper bearing an image formed by the MFP 100, and a punching mechanism for punching holes.

[0048] Figure 2 This is a schematic cross-sectional view illustrating an example of the internal structure of the main body of an MFP. (See reference...) Figure 2 The document reading unit 130 has a rectangular reading surface for reading documents. The reading surface is formed, for example, from pressure glass and is configured horizontally. The automatic document transport device 120 is connected to the main body of the MFP100 in a manner that allows it to rotate around an axis parallel to one side of the reading surface, and can be opened and closed. The document reading unit 130 is positioned below the automatic document transport device 120, and in the open state (rotated and open), the reading surface of the document reading unit 130 is exposed. Therefore, the user can place a document on the reading surface of the document reading unit 130. The automatic document transport device 120 can change its state between an open state (with the reading surface of the document reading unit 130 exposed) and a closed state (with the reading surface covered).

[0049] The original document reading unit 130 exposes an image of the original document placed on the original document glass 11 by the exposure lamps 13A and 13B mounted on the slider 12. The slider 12 moves below the original document glass 11 in the sub-scanning direction shown by the arrow in the figure. The exposure lamps 13A and 13B are shaped to extend along the main scanning direction perpendicular to the sub-scanning direction. Reflected light from the original document is guided by the lens 16 through the mirror 14 and two mirrors 15 and 15A, and imaged by the CCD (Charge Coupled Device) sensor 18.

[0050] In the sub-scanning direction of the original document, exposure lamps 13A and 13B are positioned at different locations. Furthermore, in the sub-scanning direction, a mirror 14 is positioned between exposure lamps 13A and 13B. Therefore, the first angle of incidence of light from exposure lamp 13A onto the original document and the second angle of incidence of light from exposure lamp 13B onto the original document are different when light from exposure lamp 13A reaches the mirror 14 after exposure lamps 13A and 13B, respectively. In the sub-scanning direction, exposure lamp 13A is located on the negative side relative to mirror 14, and exposure lamp 13B is located on the positive side relative to mirror 14. Therefore, when a crease intersecting the scanning direction exists, the first and second angles of incidence change before and after the crease, respectively. This change is different between exposure lamps 13A and 13B.

[0051] The CCD sensor 18 has multiple photoelectric conversion elements arranged in the main scanning direction. The reflected light imaged by the CCD sensor 18 is converted into image data as an electrical signal within the CCD sensor 18. The image data is converted into cyan (C), magenta (M), yellow (Y), and black (K) printing data and output to the image forming unit 140.

[0052] The image forming unit 140 includes developing devices 24Y, 24M, 24C, and 24K corresponding to yellow, magenta, cyan, and black, respectively; photosensitive drums 23Y, 23M, 23C, and 23K; exposure units 21Y, 21M, 21C, and 21K; primary transfer rollers 25Y, 25M, 25C, and 25K; and toner bottles 41Y, 41M, 41C, and 41K. Here, "Y", "M", "C", and "K" represent yellow, magenta, cyan, and black, respectively.

[0053] For the developing apparatus 24Y, 24M, 24C, 24K, photosensitive drums 23Y, 23M, 23C, 23K, exposure units 21Y, 21M, 21C, 21K, primary transfer rollers 25Y, 25M, 25C, 25K, and toner bottles 41Y, 41M, 41C, 41K, only the color of the toner being processed differs. Therefore, here, the developing apparatus 24Y, photosensitive drum 23Y, exposure unit 21Y, primary transfer roller 25Y, and toner bottle 41Y used to form a yellow image will be described.

[0054] Toner bottle 41Y contains yellow developer. The developer comprises a non-magnetic toner and a magnetic carrier. Toner bottle 41Y is rotated by a toner bottle motor, discharging the developer to the outside. The developer discharged from toner bottle 41Y is supplied to developing apparatus 24Y. Toner bottle 41Y supplies developer to developing apparatus 24Y when the remaining amount of developer contained in developing apparatus 24Y falls below a predetermined lower limit.

[0055] The intermediate transfer belt 30 is suspended in a non-slackening manner by the drive roller 33 and the driven roller 34. If the drive roller 33 is in Figure 1 If the intermediate transfer belt 30 rotates counterclockwise, it will rotate counterclockwise at a specified speed as shown in the figure. As the intermediate transfer belt 30 rotates, the driven roller 34 rotates counterclockwise.

[0056] The developing unit 24Y is replenished with developer from the toner bottle 41Y to develop the electrostatic latent image formed on the photosensitive drum 23Y, thereby forming a toner image on the photosensitive drum 23Y. The toner image formed on the photosensitive drum 23Y is transferred to the intermediate transfer belt 30 via the primary transfer roller 25Y. The timing of the developing unit 24Y transferring the toner image onto the intermediate transfer belt 30 is adjusted by detecting the reference mark attached to the intermediate transfer belt 30.

[0057] When forming a full-color image, the MFP100 drives all of the developing units 24Y, 24M, 24C, and 24K. This overlays toner images of yellow, magenta, cyan, and black onto the intermediate transfer belt 30. When forming a monochrome image, the MFP100 drives any one of the developing units 24Y, 24M, 24C, and 24K. Furthermore, it is possible to combine two or more of the developing units 24Y, 24M, 24C, and 24K to form an image.

[0058] Paper boxes 35, 35A, and 35B are respectively provided with paper of different sizes. The paper contained in paper boxes 35, 35A, and 35B is fed to the conveying path by take-out rollers 36, 36A, and 36B respectively installed in paper boxes 35, 35A, and 35B, and is conveyed to the timing roller 31 by paper feeding roller 37.

[0059] The timing roller 31 feeds the paper, which is conveyed by the paper feed roller 37, into the gap between the intermediate transfer belt 30 and the secondary transfer roller 26, which serves as a transfer component. The secondary transfer roller 26 generates an electric field in the gap. Under the action of the electric field force in this gap, the toner image formed on the intermediate transfer belt 30 is transferred to the paper conveyed by the timing roller 31. The paper with the toner image transferred is conveyed to the fixing roller 32, where it is heated and pressurized. As a result, the toner melts and is fixed onto the paper. Afterward, the paper is discharged onto the paper discharge tray 39. A belt cleaning blade 29 is provided upstream of the developing device 24Y of the intermediate transfer belt 30. The belt cleaning blade 29 removes any toner residue that has not been transferred to the paper on the intermediate transfer belt 30.

[0060] Furthermore, here we will describe an example of the MFP100 using a series configuration of developing units 24Y, 24M, 24C, and 24K, which are equipped with four different colors of toner that are formed on the paper respectively. However, a four-cycle method in which the four colors of toner are transferred to the paper sequentially using a single photosensitive drum can also be used.

[0061] Figure 3 This is a diagram showing the internal structure of the post-processing unit. (Refer to...) Figure 3 The post-processing apparatus 200 includes a first mechanism M1 for performing Z-fold processing and a second mechanism M2 for performing center fold processing and triple fold processing. The first mechanism M1 performs Z-fold processing by folding the paper into a Z-shape by performing a mountain fold on one of the two creases after dividing the paper into thirds and a valley fold on the other. The second mechanism M2 performs center fold processing by performing a mountain fold on the center crease to bend the paper, and triple fold processing by performing mountain folds on each of the two creases after dividing the paper into thirds to bend the paper into a triple fold state.

[0062] The first conveying path R1 is the paper conveying path connecting the paper receiving port 201 and the first discharge port 202. Starting from the upstream of the first conveying path R1, the paper receiving port 201, branch point 204, first mechanism M1, conveying roller pair 205, and first discharge port 202 are arranged sequentially. A branch point 204 is provided between the paper receiving port 201 and the first mechanism M1 in the first conveying path R1. A switching guide 204A is provided at the branch point 204.

[0063] The second conveying path R2 is the paper conveying path connecting the branch point 204 and the second mechanism M2. The branch point 204, conveying roller pairs 207 and 208, and the second mechanism M2 are arranged sequentially starting from the upstream of the second conveying path R2.

[0064] Paper discharged from the main body 101 of the MFP100 is received by the paper receiving port 201. Without setting up post-processing of the paper, the switching guide 204A switches to the first transport path R1 side. The paper received by the paper receiving port 201 is transported along the first transport path R1, and discharged from the first discharge port 202 to the paper discharge tray 203 via the first mechanism M1 and the transport roller pair 205. With setting up Z-folding of the paper, the paper is transported along the first transport path R1 and Z-folded at the first mechanism M1. The paper that has undergone Z-folding at the first mechanism M1 is discharged from the first discharge port 202 to the paper discharge tray 203 via the transport roller pair 205.

[0065] When the paper is set to undergo a center fold or a third fold, the switching guide 204A switches to the second transport path R2. Paper from the paper receiving port 201 is transported along the first transport path R1 to the branch point 204, and then enters the second transport path R2. Paper entering the second transport path R2 is transported to the second mechanism M2 via transport rollers 207 and 208. Paper that has undergone a center fold or third fold in the second mechanism M2 is discharged through the upper side of the third fold gate 225 to the second discharge outlet 209.

[0066] <Middle Folding Process>

[0067] The folding process is performed by the second mechanism M2. The second mechanism M2 includes a first folding roller 211, a second folding roller 212, a folding knife 213, an auxiliary tray 214, a stacking tray 215, a limiter 216, and a positioning motor 217.

[0068] Stacking tray 215 and auxiliary tray 214 each have a stacking surface for stacking paper. The stacking surface is flat. Stacking tray 215 and auxiliary tray 214 are positioned such that the stacking surface of stacking tray 215 and the stacking surface of auxiliary tray 214 are in the same plane. Stacking tray 215 and auxiliary tray 214 are respectively configured such that their stacking surfaces are tilted from vertical at a predetermined angle. Auxiliary tray 214 is arranged at a predetermined interval from stacking tray 215 in the paper conveying direction. Paper conveyed in the second conveying path R2 is stacked on stacking tray 215 and auxiliary tray 214 respectively.

[0069] A limiter 216 is disposed at the lower end of the stacking tray 215. The position of the paper relative to the stacking tray 215 is defined by the front end of the paper abutting against the limiter 216 in the paper's transport direction. The limiter 216 is connected to the stacking tray 215 in a manner that allows it to move along the paper's transport direction, which is parallel to the stacking surface of the stacking tray 215. A positioning motor 217 moves the limiter 216 on the stacking tray 215. The positioning motor 217 is a stepper motor that defines the relative position of the limiter 216 relative to the stacking tray 215. The positioning motor 217 determines the relative position of the limiter 216 and the stacking tray 215 based on the paper's size. Furthermore, the positioning motor 217 fine-tunes the relative position of the limiter 216 and the stacking tray 215.

[0070] A folding knife 213, a first folding roller 211, and a second folding roller 212 are arranged between the auxiliary tray 214 and the stacking tray 215. The combination of the first folding roller 211 and the second folding roller 212 and the folding knife 213 are arranged on opposite sides of the respective stacking surfaces of the auxiliary tray 214 and the stacking tray 215.

[0071] The first folding roller 211 and the second folding roller 212 are arranged opposite each other. The rotation axis of the first folding roller 211 applies force toward the rotation axis of the second folding roller 212. A folding blade 213 is arranged opposite to the folding portion that contacts the first folding roller 211 and the second folding roller 212. As shown by arrow AR1, the folding blade 213 is movable in a direction perpendicular to the respective folding surfaces of the stacking tray 215 and the auxiliary tray 214, and is driven by a drive motor.

[0072] With one or more sheets of paper stacked on the stacking tray 215 and auxiliary tray 214, the center folding knife 213 moves toward the center folding section where the first center folding roller 211 and the second center folding roller 212 contact. As the center folding knife 213 moves, the bundle of one or more sheets of paper stacked on the stacking tray 215 and auxiliary tray 214 is pressed into the center folding section. Thus, the bundle of paper is introduced through the first center folding roller 211 and the second center folding roller 212 and folded. The bundle of paper is discharged through the first center folding roller 211 and the second center folding roller 212 to the second discharge outlet 209.

[0073] <30% off>

[0074] Figures 4-6 This is a diagram used to illustrate the three-fold processing based on the second mechanism. Figures 4-6 It is magnification Figure 3 The diagram shows region F. (Refer to...) Figures 4-6 The second mechanism M2 performs the three-fold process. In addition to the first folding roller 211, the second folding roller 212, the folding knife 213, the auxiliary tray 214, the stacking tray 215, the limiter 216, and the positioning motor 217, the second mechanism M2 also includes a three-fold knife 221, a drive gear 222, a three-fold roller 223, a three-fold roller 224, and a three-fold door 225.

[0075] The three-fold process involves folding the paper into two equal sections along two creases. The folding at the first crease is called the first fold, and the folding at the second crease is called the second fold. The position of the limiter 216 in the first fold differs from that in the middle fold, but the other operations are the same. In the middle fold, the position of the limiter 216 is determined by the distance from the limiter 216 to the position where the middle fold cutter 213 is positioned, which is half the length of the paper in the paper's transport direction. Conversely, in the first fold, the position of the limiter 216 is determined by the distance from the limiter 216 to the position where the middle fold cutter 213 is positioned, which is one-third the length of the paper in the paper's transport direction.

[0076] The three-fold roller 224 and the second intermediate roller 212 are arranged opposite each other. The rotation axis of the three-fold roller 224 applies force toward the rotation axis of the second intermediate roller 212.

[0077] A three-fold blade 221 is disposed opposite to the three-fold section that contacts the three-fold roller 224 and the second middle fold roller 212. The three-fold blade 221 can move along... Figure 4 The arrows at both ends indicate movement. The three-fold blade 221 has multiple slots formed at equal intervals on the surface opposite the drive gear 222. The drive gear 222 is mounted on the rotation shaft 221A of the first intermediate folding roller 211 in a manner that allows it to rotate independently of the first intermediate folding roller 211. The drive gear 222 has a peripheral portion at the same distance from the rotation shaft 221A. Gears are formed on the peripheral portion that mesh with the multiple slots formed in the three-fold blade 221. The drive gear 222 is rotated by being driven by a stepper motor. As the drive gear 222 rotates, the three-fold blade 221 moves along... Figure 4 The arrows at both ends indicate movement. The position of the three-fold blade 221 is determined by a stepper motor. In other words, the position of the three-fold blade 221 is determined by controlling the rotation angle of the stepper motor.

[0078] The tri-fold door 225 is rotatable about a rotation axis 225A. The tri-fold door 225 has an abutment surface. During the first folding process, the tri-fold door 225 is positioned with the abutment surface facing the center fold. A bundle of paper conveyed from the center fold, which is in contact with the first center fold roller 211 and the second center fold roller 212, abuts against the abutment surface of the tri-fold door 225.

[0079] Through the first folding process, such as Figure 4 As shown, the bundle of paper introduced by the first folding roller 211 and the second folding roller 212, with the folded portion as the leading end, is conveyed towards the three-fold gate 225 via the first folding roller 211 and the second folding roller 212. The leading end of the bundle of paper abuts against the contact surface of the three-fold gate 225, and then the leading end of the bundle of paper is guided along the contact surface.

[0080] Reference Figure 5 At the moment when the first folding roller 211 and the second folding roller 212 rotate by a predetermined rotation angle, the triple-fold cutter 221 moves toward the triple fold as indicated by arrow AR2. The timing of the movement of the triple-fold cutter 221 is determined so that the tip of the triple-fold cutter 221 abuts against the second crease of the paper. For example, the timing of the movement of the triple-fold cutter 221 is determined when a predetermined time has elapsed since the middle fold cutter 213 began moving toward the middle fold. The predetermined time is determined based on the rotational speed of the first folding roller 211 and the second folding roller 212 and the size of the paper.

[0081] If the folding cutter 221 moves toward the fold section as indicated by arrow AR2, the portion of the paper with the second fold is pressed into the fold section by the folding cutter 221. Thus, the bundle of paper is introduced by the folding roller 224 and the second intermediate folding roller 212, and undergoes a mountain fold.

[0082] Reference Figure 6The bundle of paper that has been folded by the three-fold roller 224 and the second intermediate fold roller 212 is conveyed between the three-fold roller 224 and the three-fold roller 223 and discharged to the second discharge outlet 209.

[0083] <Z-fold processing>

[0084] Reference Figure 3 When the setting is to perform Z-folding processing on the paper, the paper discharged from the main body 101 of the MFP100 enters the first transport path R1 from the paper receiving port 201 and is transported to the first mechanism M1.

[0085] Figure 7 as well as Figure 8 This is a diagram used to illustrate the Z-fold processing based on the first mechanism. Figure 7 as well as Figure 8 This is a diagram showing the first mechanism M1 magnified. (Refer to...) Figure 7 The first mechanism M1 has a first Z-folding roller 231, a second Z-folding roller 232, a third Z-folding roller 233, a folding hook 234, and a folding guide 235.

[0086] The rotation axes of the first Z-fold roller 231, the second Z-fold roller 232, and the third Z-fold roller 233 are parallel. The rotation axis of the second Z-fold roller 232 applies force to the rotation axis of the third Z-fold roller 233, forming a first Z-fold portion where the second Z-fold roller 232 contacts the third Z-fold roller 233. Additionally, the rotation axis of the first Z-fold roller 231 applies force to the rotation axis of the third Z-fold roller 233, forming a second Z-fold portion where the first Z-fold roller 231 contacts the third Z-fold roller 233.

[0087] The folding hook 234 is mounted above the second Z-folding roller 232 and is rotatable about the rotation axis 234A. By rotating, the folding hook 234 can move to a retracted position that does not intersect the first conveying path R1 and a folded position that intersects the first conveying path R1. When the folding hook 234 is in the folded position, as... Figure 7 As shown, the front end of the folding hook 234 is located between the second Z-folding roller 232 and the third Z-folding roller 233.

[0088] The folding guide 235 is mounted above the folding hook 234 and is rotatable about the rotation axis 235A. By rotating, the folding guide 235 can move to a retracted position that does not overlap with the folding hook 234 when viewed from the side, and to a folded position that forms part of the upper end of the first conveying path R1. In the folded position, the folding guide 235 has a limiting surface at its lower end. When the folding guide 235 is in the folded position, the limiting surface of the folding guide 235 forms part of the upper end of the first conveying path R1. Furthermore, the end of the limiting surface on the side of the first Z-folding roller 231 is located between the first Z-folding roller 231 and the third Z-folding roller 233.

[0089] During the stage where paper is conveyed from the paper receiving port 201 on the first conveying path R1, the folding guide 235 and the folding hook 234 are respectively in the retracted position, and the third Z-folding roller 233 rotates counterclockwise. The first Z-folding roller 231 is the driven roller, rotating clockwise along with the rotation of the third Z-folding roller 233. The paper conveyed on the first conveying path R1 is transported by the first Z-folding roller 231 and the third Z-folding roller 233.

[0090] At the moment when the third Z-folding roller 233 rotates by a predetermined rotation angle, the third Z-folding roller 233 reverses its direction, and the folding hook 234... Figure 7 The paper is moved to the folded position as shown. The timing of the reversal of the third Z-fold roller 233 and the timing of the movement of the folding hook 234 are determined so that the tip of the folding hook 234 abuts against the first crease of the paper. The timing of the reversal of the third Z-fold roller 233 and the timing of the movement of the folding hook 234 are determined based on the distance the third Z-fold roller 233 has transported the paper.

[0091] For example, a paper detection sensor is installed downstream of the third Z-fold roller 233 in the first conveying path R1, and the paper position is determined based on the amount of rotation of the third Z-fold roller 233 from the time the paper is detected by the sensor. Then, based on the determined paper position and the amount of rotation of the third Z-fold roller 233, the timing of the reversal of the third Z-fold roller 233 and the timing of the movement of the folding hook 234 are determined.

[0092] If the third Z-fold roller 233 reverses, it rotates clockwise. The second Z-fold roller 232, being the driven roller, rotates counterclockwise in tandem with the rotation of the third Z-fold roller 233. The paper is pressed into the first Z-fold between the third Z-fold roller 233 and the second Z-fold roller 232 via the folding hook 234. Thus, the paper is guided by the third Z-fold roller 233 and the second Z-fold roller 232 and undergoes a valley fold. The paper is conveyed a predetermined distance via the third Z-fold roller 233 and the second Z-fold roller 232.

[0093] The distance that the third Z-fold roller 233 and the second Z-fold roller 232 convey the paper is equivalent to 1 / 3 of the length in the paper's conveying direction, and is determined by the amount of rotation of the third Z-fold roller 233. For example, the distance the paper is conveyed can also be determined by measuring the time elapsed since the third Z-fold roller 233 reverses direction.

[0094] If the third Z-fold roller 233 and the second Z-fold roller 232 have conveyed the paper a predetermined distance, the third Z-fold roller 233 reverses direction, and the folding hook 234 moves to the retracted position, while the folding guide 235 moves to the folding position. If the third Z-fold roller 233 reverses direction, it rotates counterclockwise, the second Z-fold roller 232 rotates clockwise, and the first Z-fold roller 231 rotates clockwise. The portion of the paper sandwiched between the third Z-fold roller 233 and the second Z-fold roller 232 moves upward, and the rear end of the paper is conveyed downstream of the first conveying path R1, so a portion of the paper comes into contact with the limiting surface of the folding guide 235. Thus, the paper is guided by the limiting surface of the folding guide 235 and pressed into the second Z-fold portion between the third Z-fold roller 233 and the first Z-fold roller 231. Thus, the paper is introduced by the third Z-fold roller 233 and the first Z-fold roller 231 and undergoes a mountain fold.

[0095] The paper is conveyed by the third Z-folding roller 233 and the first Z-folding roller 231, through the first conveying path R1, and discharged from the first discharge outlet 202 by the conveying roller pair 205.

[0096] Figure 9 This is a block diagram illustrating the general hardware configuration of an MFP. (See reference...) Figure 9 The MFP100 includes a main circuit 110. The main circuit 110 includes a CPU (Central Processing Unit) 111 for controlling the entire MFP100, a communication interface (I / F) unit 112, a ROM (Read-Only Memory) 113, a RAM (Random Access Memory) 203, an EPROM (Erasable Programmable ROM) 114 for non-volatile data storage, an HDD (Hard Disc Drive) 115 as a large-capacity storage device, a fax unit 116, and an external storage device 117. The CPU 111 is connected to the automatic document feeder 120, the document reader 130, the image forming unit 140, the paper feeder 150, the operation panel 160, and the post-processing unit 200, controlling the entire MFP100.

[0097] ROM 113 stores the program executed by CPU 111 or the data required to execute the program. RAM 114 is used as the working area when CPU 111 executes the program. In addition, RAM 114 temporarily stores image data continuously sent from the original document reading unit 130.

[0098] The operation panel 160 is provided on the upper surface of the MFP100. The operation panel 160 includes a display unit 161 and an operation unit 163. The display unit 161 is, for example, a liquid crystal display (LCD) device, which displays instruction menus for the user, information related to the acquired image data, etc. In addition, instead of an LCD, any device that displays images can be used, such as an organic EL (electroluminescence) display.

[0099] The operation unit 163 includes a touch panel 165 and a hard key unit 167. The touch panel 165 is of the electrostatic capacitive type. However, the touch panel 165 is not limited to the electrostatic capacitive type; for example, it can use other types such as resistive film type, surface elastic wave type, infrared type, electromagnetic induction type, etc.

[0100] The detection surface of the touch panel 165 is disposed overlapping the upper or lower surface of the display unit 161. Here, the size of the detection surface of the touch panel 165 is the same as the size of the display surface of the display unit 161. Therefore, the coordinate system of the display surface is the same as the coordinate system of the detection surface. The touch panel 165 detects the position indicated by the user to the display surface of the display unit 161 on the detection surface and outputs the coordinates of the detected position to the CPU 111. Since the coordinate system of the display surface is the same as the coordinate system of the detection surface, the coordinates output by the touch panel 165 can be replaced with the coordinates of the display surface.

[0101] The hard key section 167 includes multiple hard keys. These hard keys may be, for example, contact switches. The touch panel 165 detects the position indicated by the user on the display surface of the display unit 161. Since users often operate the MFP100 in an upright posture, the display surface of the display unit 161, the operating surface of the touch panel 165, and the hard key section 167 are configured to face upwards. This is to allow the user to easily visually confirm the display surface of the display unit 161 and to easily point to the operating unit 163 with their finger.

[0102] The Communication I / F Unit 112 is an interface used to connect the MFP100 to a network. The Communication I / F Unit 112 uses communication protocols such as TCP (Transmission Control Protocol) or UDP (User Datagram Protocol) to communicate with other computers connected to the network. Furthermore, the network connected to the Communication I / F Unit 112 is a Local Area Network (LAN), and the connection method can be either wired or wireless. However, the network is not limited to a LAN; it can also be a Wide Area Network (WAN), a Public Switched Telephone Network (PSTN), the Internet, etc.

[0103] The fax unit 116 is connected to the Public Switched Telephone Network (PSTN) and sends fax data to or receives fax data from the PSTN. The fax unit 116 stores the received fax data in the HDD 115, converts it into printable data that can be printed in the image forming unit 140, and outputs it to the image forming unit 140. Thus, the image forming unit 140 forms an image of the fax data received by the fax unit 116 on paper. Additionally, the fax unit 116 converts the data stored in the HDD 115 into fax data and sends it to a fax device connected to the PSTN.

[0104] The external storage device 117 is controlled by the CPU 111 and contains a CD-ROM (Compact Disk Read Only Memory) 118 or a semiconductor memory. In this embodiment, an example of the CPU 111 executing a program stored in the ROM 113 is described, but the CPU 111 can also control the external storage device 117 to read a program for execution from the CD-ROM 118, store the read program in the RAM 114, and execute it.

[0105] Furthermore, the recording medium for storing programs executed by the CPU 111 is not limited to CD-ROM 118, but may also be a floppy disk, magnetic tape, optical disc (MO (Magnetic Optical Disc) / MD (Mini Disc) / DVD (Digital Versatile Disc)), IC card, optical card, mask ROM, EPROM (Erasable Programmable ROM) and other semiconductor memory media.

[0106] Furthermore, the CPU 111 can download a program from a network-connected computer and store it in the HDD 115, or the network-connected computer can write the program to the HDD 115, and the CPU 111 will load the program stored in the HDD 115 into the RAM 114 and execute it. The program referred to here includes not only programs that can be directly executed by the CPU 111, but also source programs, compressed programs, encrypted programs, etc.

[0107] Figure 10 This is a block diagram illustrating an example of the functions of the CPU in an MFP. The CPU 111 in the MFP100 performs its functions by executing a post-processing position adjustment program stored in ROM 113, HDD 115, or CD-ROM 118. (See reference...) Figure 10 The CPU 111 includes an image forming control unit 51, a reading control unit 53, a relative orientation determination unit 55, a relative position determination unit 57, a correction amount determination unit 61, a notification unit 63, and a correction unit 65.

[0108] The reading control unit 53 controls the original document reading unit 130 to scan the image formed on the original document. The reading control unit 53 outputs the data obtained from scanning the original document as reading data to the relative position determination unit 57.

[0109] The reading control unit 53 controls the original document reading unit 130 to read the original document in either normal mode or crease detection mode. When the original document reading unit 130 reads the original document in normal mode, the reading control unit 53 scans the original document with either or both of the exposure lamps 13A and 13B emitting light, and acquires the image data output by the CCD sensor 18 as the original document data. The reading control unit 53 outputs the original document data to the image forming control unit 51 and the relative position determination unit 57.

[0110] When the original document reading unit 130 reads the original document in crease detection mode, the reading control unit 53 scans the original document with either exposure lamp 13A or 13B emitting light and acquires first image data output by the CCD sensor 18. Then, it scans the original document with the other exposure lamp 13A or 13B emitting light and acquires second image data output by the CCD sensor 18. When the original document reading unit 130 reads the original document in crease detection mode, the reading control unit 53 reads the area containing the outline of the original document. The reading control unit 53 outputs the first image data and the second image data as reading data to the relative position determination unit 57. The first angle of incidence of light from exposure lamp 13A onto the original document is different from the second angle of incidence of light from exposure lamp 13B onto the original document. Therefore, when a crease intersects the sub-scanning direction, the brightness changes before and after the crease in the first and second image data are different.

[0111] The image forming control unit 51 controls the image forming unit 140 and the paper feeding unit 150 to perform image forming processing on the paper, and controls the post-processing device 200 to perform post-processing to process the paper on which the image has been formed. Post-processing includes center folding, triple folding, and Z-folding. The image forming control unit 51 forms an image of the image data onto the paper. The image data includes original data obtained by reading the original through the reading control unit 53, print data received from an external source, and image data stored in the HDD 115. The image forming control unit 51 outputs paper information related to the paper on which the image has been formed to the relative orientation determination unit 55. The paper information includes the paper size, the paper transport direction, and the image forming direction. The transport direction refers to either the long side direction or the short side direction of the paper. For example, when the paper is transported with its long side direction parallel to the transport direction, the transport direction refers to the long side direction; when the paper is transported with its short side direction parallel to the transport direction, the transport direction refers to the short side direction. The image forming direction refers to the direction of the image formed on the paper, and can be either the longitudinal or transverse direction. The image forming data is defined vertically. When the image is formed with the long side of the paper parallel to the vertical direction of the image, it is represented as portrait orientation; when the image is formed with the short side of the paper parallel to the vertical direction of the image, it is represented as landscape orientation. Furthermore, the image forming control unit 51 outputs the forming data to the relative position determination unit 57.

[0112] The relative orientation determination unit 55 determines the relative orientation based on the paper information, which is determined according to the orientation of the image formed on the paper and the orientation of the paper. Here, the relative orientation is defined as the orientation of the leading edge of the paper's transport direction relative to the orientation of the image formed on the paper. In other words, the relative orientation represents any one of the vertical, horizontal, or vertical orientations of the image formed on the paper. The relative orientation determination unit 55 determines the relative orientation based on the paper information.

[0113] The relative orientation determination unit 55 determines the relative orientation based on the paper transport direction and the image forming direction. Specifically, when the paper transport direction is along its long side and the image forming direction is vertical, the relative orientation determination unit 55 determines the top of the image as the relative orientation; when the paper transport direction is along its long side and the image forming direction is horizontal, it determines the left side of the image as the relative orientation. Furthermore, when the paper transport direction is along its short side and the image forming direction is vertical, the relative orientation determination unit 55 determines the left side of the image as the relative orientation; when the paper transport direction is along its short side and the image forming direction is horizontal, it determines the top of the image as the relative orientation.

[0114] The relative position determination unit 57 parses the read data and determines the reference edge in the read data. The relative position determination unit 57 includes a crease extraction unit 71, a contour extraction unit 73, and a reference determination unit 75.

[0115] The crease extraction unit 71 parses the read data and extracts the crease portion. The read data includes first image data and second image data. In the first image data and second image data, the brightness before and after the crease portion differs in the sub-scanning direction. Furthermore, the crease portion is a straight line intersecting the sub-scanning direction. For example, the crease extraction unit 71 generates composite data where the values ​​of pixels at the same position in the first image data and the second image data are set to lower brightness values, and differential data consisting of pixels in the first image data and the second image data whose brightness difference is above a predetermined value. The crease portion is extracted based on either the composite data or the differential data. The crease extraction unit 71 defines the set of multiple pixels in the composite data whose brightness is below a predetermined value and forms a straight line as the crease portion. Similarly, the crease extraction unit 71 defines the set of multiple pixels in the differential data whose brightness difference is below a predetermined value and forms a straight line as the crease portion.

[0116] Figure 11 This is a diagram representing an example of synthetic data. Figure 11 The composite data shown represents data generated from a first image data obtained by unfolding the inner side of a folded sheet of paper to create a reading surface and reading the image, along with a second image data. (Refer to...) Figure 11 In the composite data, the outline of the paper is shown as a rectangle.

[0117] Additionally, there are cases where the light irradiated by exposure lamps 13A and 13B does not reach the areas where valley folds have occurred. In these areas, pixels with lower brightness are shown in the composite data generated based on the first image data and the second image data. It is possible to extract the set of pixels forming a straight line of a predetermined length from the lower-brightness areas in the composite data as fold lines.

[0118] Figure 12 This is a graph representing an example of differenced data. Figure 12 The differential data shown represents the differential data generated from the first image data and the second image data obtained by unfolding the outer side of a folded sheet to form the reading surface and reading it. (Refer to...) Figure 12 In the differential data, the outline of the paper is shown as a rectangle.

[0119] Furthermore, the portions on both sides of the crease formed by the mountain-shaped fold include areas that are reached by light emanating from either of the exposure lamps 13A and 13B, but not by light emanating from the other. Therefore, the difference data generated based on the first image data and the second image data includes pixels whose pixel values ​​differ from those in the first image data and the second image data, and pixels whose pixel value difference is less than a predetermined value. In the difference data, the set of pixels forming a straight line of predetermined length, sandwiched between a set of pixels whose brightness difference is greater than or equal to a predetermined value, is extracted as the crease.

[0120] Return to Figure 10 The contour extraction unit 73 parses the read data and extracts the contour portion of the paper. In the read data, the paper contour appears in at least one of the first image data and the second image data. The paper contour portion is rectangular. For example, the contour extraction unit 73 generates composite data by setting the pixel values ​​of pixels at the same position in the first and second image data to values ​​with smaller pixel values, and extracts the rectangular portion of the composite data whose image values ​​are below a predetermined value as the contour portion. Alternatively, the contour extraction unit 73 can also extract from the composite data a rectangle surrounding the portion that corresponds to the forming data input from the image forming control unit 51.

[0121] The reference determination unit 75 determines, from the four sides of the outline portion in the read data, the side located in the relative direction determined by the relative direction determination unit 55 as the reference edge. First, the reference determination unit 75 determines the direction of the outline portion based on the direction of the portion in the read data that corresponds to the forming data. Since the image of the forming data determines the top, bottom, left, and right, the top, bottom, left, and right of the image of the read data are determined. Then, the reference determination unit 75 determines, from the four sides constituting the outline portion in the read data, the side located in the relative direction determined by the relative direction determination unit 55 as the reference edge. Thus, the edge corresponding to the leading edge in the paper's transport direction among the four sides constituting the outline portion in the read data is determined as the reference edge.

[0122] The correction amount determination unit 61 receives the relative position of the crease relative to the paper from the relative position determination unit 57. Based on the relative position, the correction amount determination unit 61 determines the correction amount. The correction amount determination unit 61 compares the relative position with a predetermined value for the paper and determines the difference between the relative position and the predetermined value as the correction amount. In the case of performing a middle fold, half the length of the paper in the transport direction is determined as the predetermined value. In the case of performing a triple fold or a Z-fold, one-third of the length of the paper in the transport direction is determined as the predetermined value. The correction amount is determined by subtracting the predetermined value from the relative position. The correction amount determination unit 61 outputs the determined correction amount to the notification unit 63 and the correction unit 65.

[0123] The notification unit 63 notifies the user of the correction amount determined by the correction amount determination unit 61. For example, the correction amount adjustment screen is displayed on the display unit 161. The correction amount adjustment screen contains the correction amount.

[0124] The correction unit 65 adjusts the post-processing device 200 based on the correction amount determined by the correction amount determination unit 61. Specifically, when the correction amount is for a middle fold, the position of the limiter 216 is changed by the correction amount. When the correction amount is for a three-fold, the position of the limiter 216 is changed by the correction amount, and the timing for driving the three-fold cutter 221 is changed by the time corresponding to the correction amount. When the correction amount is for a Z-fold, the timing for the first reverse rotation of the third Z-fold roller 233 and the timing for moving the folding hook 234 to the folding position are changed by the time corresponding to the correction amount, and the timing for the second reverse rotation of the third Z-fold roller 233 and the timing for moving the folding guide 235 to the folding position are changed by the time corresponding to the correction amount.

[0125] Figure 13 This is an example image showing the adjustment screen for corrective adjustments. (See reference.) Figure 13This includes a correction adjustment screen, the current adjustment value, a sample, and a correction value. The current adjustment value represents the difference relative to the reference value. Here, the current adjustment value is shown as 0.0mm. The sample represents the difference between the actual crease position and the predetermined crease position. Here, it is shown as -0.5mm. The actual crease position is represented by the distance from the reference edge to the crease detected from the read data. The predetermined crease position represents the ideal crease specified for the paper, expressed as the distance between the crease and the reference edge. The predetermined crease position is predetermined relative to the paper size and transport direction. The correction value represents the amount of correction relative to the setting value set for the post-processing device 200. Here, it is shown as +0.5mm. The correction amount is a value determined based on the sample. Thus, it indicates that the setting value set for the post-processing device 200 will be corrected, and the user is notified that the correction will be made so that the difference between the crease and the ideal crease is 0. A + button and a - button are shown in the column displaying the correction value, allowing the user to change the correction value. After the + and - buttons are used to change the correction value, if the OK button is pressed, the setting value set in the post-processing device 200 will be corrected with the changed correction value.

[0126] Figure 14 This is a flowchart illustrating an example of the image forming process. The image forming process is performed by the CPU 111, which executes a post-processing position adjustment program stored in ROM 113, HDD 115, or CD-ROM 118. (See reference...) Figure 14 The CPU 111 accepts the image forming settings (step S01) and proceeds to step S02. It accepts user input to the operation panel 160, specifically settings for the image forming unit 140 to form an image. These settings include the paper size, paper transport direction, and image forming direction. When the original document reading unit 130 reads the original document, the settings for the original document reading unit 130 to read the original document are also accepted.

[0127] In step S02, the post-processing setting is accepted, and the process proceeds to step S03. The setting input by the user on the operation panel 160 is accepted, and this setting is for causing the post-processing device 200 to perform post-processing. The post-processing includes a folding process. The folding process includes any one of a center fold, a tri-fold, or a Z-fold. In step S03, it is determined whether a test output instruction has been accepted. If the user inputs a test output instruction on the operation panel 160, it is determined that a test output instruction has been accepted. If the test output instruction has been accepted, the process proceeds to step S04; otherwise, the process returns to step S01. Furthermore, steps S01 and S02 can be performed in reverse order or simultaneously.

[0128] In step S04, a test output is performed on one copy, and the process proceeds to step S05. The CPU 111 controls the image forming unit 140 to form an image on the paper according to the image forming settings set in step S01, and causes the post-processing device 200 to perform post-processing according to the post-processing settings set in step S02. Even if multiple image formings are set in the image forming settings, the CPU 111 only performs image forming on one copy and performs post-processing on it.

[0129] In step S05, output image reading processing is performed, and the process proceeds to step S06. The paper output after image formation and post-processing in step S04 has creases. If the user unfolds the paper and places it on the original document glass 11, and then presses the start button, output image reading processing is performed. In step S06, post-processing position adjustment processing is performed, and the process proceeds to step S07. Although the output image reading processing and post-processing position adjustment processing are described in detail later, these processes are essentially processes that read the paper output in step S04 for testing and determine the correction amount used to adjust the post-processing position.

[0130] In step S07, it is determined whether an output instruction has been accepted. If the output instruction input by the user on the operation panel 160 is accepted, the process proceeds to step S08; otherwise, the process returns to step S06.

[0131] In step S08, output is performed in units of copies, and processing proceeds to step S09. CPU 111 controls the image forming unit 140 to form an image on the paper according to the image forming settings set in step S01, and causes the post-processing device 200 to perform post-processing according to the post-processing settings set in step S02. In step S09, it is determined whether the number of image copies formed is equal to the set number of copies. If the number of image copies formed is equal to the set number of copies, processing ends; otherwise, processing returns to step S08.

[0132] Figure 15 This is a flowchart illustrating an example of the output image reading process. The output image reading process is performed in step S05 of the image forming process. Prior to performing the output image reading process, the user places a test-output sheet in an unfolded state on the original document glass 11.

[0133] Reference Figure 15CPU 111 executes the first scan (step S11) and proceeds to step S12. CPU 111 exposes the exposure lamp 13A to scan the original document. At this time, areas larger than the original document are scanned in both the sub-scanning direction and the main scan direction. In step S12, first image data is acquired. The exposure lamp 13A scans the original document, and the light reflected from the original document is received by the CCD sensor 18, acquiring the first image data output by the CCD sensor 18.

[0134] In the next step S13, a second scan is performed, and the process proceeds to step S14. CPU 111 exposes the exposure lamp 13B to scan the original document. At this time, areas larger than the original document are scanned in both the sub-scanning and main scan directions. In step S14, second image data is acquired, and the process returns to the image forming process. The exposure lamp 13B scans the original document, and the light reflected from the original document is received by the CCD sensor 18, acquiring the second image data output by the CCD sensor 18.

[0135] Figure 16 This is a flowchart illustrating an example of the post-processing position adjustment process. The post-processing position adjustment process is performed in step S06 of the image formation process. Prior to performing the post-processing position adjustment process, first image data and second image data are acquired.

[0136] Reference Figure 16 CPU 111 extracts the contour based on the first image data and the second image data (step S21), and proceeds to step S22. Synthetic data is generated by setting the values ​​of pixels at the same positions in the first and second image data to lower brightness values, and the contour portion of a rectangle is extracted based on the synthetic data. The portion of the rectangle in the synthetic data whose image values ​​are below a predetermined value is extracted as the contour portion. Alternatively, a portion consistent with the forming data that forms the basis of the image formed on paper can be extracted from the synthetic data, and the rectangle surrounding the extracted portion can be extracted as the contour portion.

[0137] In step S22, a reference edge is determined from the four edges of the contour portion, and the process proceeds to step S23. The edge that will become the leading edge of the paper in the transport direction among the four edges constituting the contour portion is determined as the reference edge. The direction of the contour portion is determined based on the direction of the portion in the composite data that is consistent with the forming data. Furthermore, the reference edge is determined based on the paper transport direction and the image forming direction.

[0138] In step S23, creases are extracted, and the process proceeds to step S24. Composite data is generated by setting the values ​​of pixels at the same position in the first and second image data to lower brightness values, and difference data is generated by consisting of pixels in the first and second image data whose brightness difference is above a predetermined value. Crease portions are extracted from either the composite data or the difference data. A set of pixels in the composite data whose brightness is below the predetermined value that form a straight line is extracted as the crease. Additionally, a set of pixels in the difference data whose brightness difference is below the predetermined value that forms a straight line is extracted as the crease.

[0139] In step S24, a correction amount is determined. The distance between the reference edge determined in step S22 and the crease determined in step S23 is compared with a predetermined value. The difference between the distance between the reference edge and the crease and the predetermined value is determined as the correction amount. The predetermined value represents the distance between the ideal crease of the paper and the leading edge of the paper in the transport direction, which is predetermined relative to the size of the paper and the transport direction.

[0140] In step S25, the correction amount is notified, and the process proceeds to step S26. For example, the display unit 161 displays... Figure 13 The correction amount adjustment screen is shown. In step S26, it is determined whether the correction instruction has been accepted. If the correction instruction is accepted by the user by clicking the OK button on the correction amount adjustment screen, the correction instruction is accepted. The system enters a standby state until the correction instruction is accepted (if not in step S26). If the correction instruction is accepted (if yes in step S26), the process proceeds to step S27.

[0141] In step S27, the set value of the post-processing device 200 is corrected according to the correction amount, and the processing ends.

[0142] <Example of a modified image with corrective adjustments>

[0143] Figure 17 This is an example diagram showing the adjustment screen for the correction amount in a modified example. (See reference...) Figure 17 The correction amount in the modified example adjusts the screen and Figure 13 The units of the values ​​displayed on the correction adjustment screen are different. In the variant example, the unit of the correction adjustment screen is %. This represents the proportion of the distance from the crease to the reference edge relative to the length of the paper in the paper's transport direction. Figure 17 In the diagram, the current adjustment value is shown as 50%. The sample, representing the proportion of the actual crease to the reference edge relative to the length of the paper, is shown as 49.5%. The correction value represents the amount of correction relative to the setting value set for the post-processing device 200. Here, +0.5% is shown. This indicates that the correction value will be adjusted relative to the setting value set for the post-processing device 200, and the user will be notified that the correction is made so that the difference between the crease and the ideal crease is 0.

[0144] As explained above, the MFP100 in this embodiment functions as an image forming apparatus, including a post-processing unit 200 that folds a piece of paper on which an image is formed. It acquires and outputs readout data that reads the region containing the outline of a folded original document in the post-processing unit 200, and determines the relative position of the original document's outline and the crease based on the readout data. Therefore, by determining the crease position based on the original document's outline in the readout data, the crease position can be determined regardless of the original document's current position at the time of reading. Thus, the position of the creases on the original document can be accurately detected.

[0145] Furthermore, the MFP100 extracts creases and contours of the original document based on first image data obtained by illuminating the original document at a first incident angle and receiving the light reflected from the original document, and second image data obtained by illuminating the original document at a second incident angle and receiving the light reflected from the original document. Because the first and second incident angles are different, regions where pixel values ​​differ between the first and second image data can be detected around the creases of the original document. Therefore, creases of the original document can be accurately detected in the image data.

[0146] Furthermore, the MFP100 determines the correction amount of the setting value set in the post-processing unit 200 based on the relative position of the outline and crease of the original artwork. Therefore, the correction amount can be easily determined based on the offset of the crease.

[0147] In addition, the MFP100 displays a correction adjustment screen containing the correction amount on the display unit 161, so it can notify the user of the correction amount, and the user can observe the correction adjustment screen to confirm the correction amount.

[0148] In addition, the MFP100 corrects the settings set in the post-processing unit 200 by a correction amount. Therefore, the settings of the post-processing unit 200 can be automatically corrected.

[0149] In addition, the MFP100 notifies the correction amount in units of length, so users can grasp the correction amount by length.

[0150] In addition, the MFP100 in the variant notifies the correction amount in units of ratio, so it is possible to notify the correction amount for multiple dimensions of paper using the same reference.

[0151] Furthermore, the MFP100 determines a reference edge from the four edges of the original document on which the image is formed on the paper, based on the transport direction and the image formation direction during image formation on the paper, to determine the relative position with respect to creases. Therefore, the reference edge can be determined based on the reading data obtained by forming the image and reading the paper as an original document.

[0152] The embodiments disclosed herein should be considered illustrative of all points and not limiting embodiments. The scope of the invention is not shown from the foregoing description, but from the claims, and includes all modifications equivalent to and within the scope of the claims.

[0153] <Postscript>

[0154] (1) According to the image forming apparatus described in item 2, the relative position determining unit extracts the crease of the original based on the synthetic data in which the pixel values ​​of the same image in the first image data and the second image data are set to a lower brightness value or as differential data as the difference between the first image data and the second image data.

[0155] Based on this, it is possible to extract the mountain folds and valley folds from the original manuscript.

[0156] (2) The image forming apparatus according to item 3 further comprises:

[0157] Image forming unit, forming an image on paper; and

[0158] The supply unit supplies paper to the image forming unit.

[0159] The aforementioned decision unit determines the setting value set in the aforementioned post-processing device based on the type of paper supplied by the aforementioned supply unit.

[0160] Based on this, the correction amount corresponding to each type of paper can be determined.

Claims

1. An image forming apparatus, wherein, have: Post-processing device, folds paper to form an image; The original manuscript reading unit reads the original manuscript. The read control unit acquires image data output by the original document reading unit from a region it reads, the region including the outline of the original document folded and creased by the post-processing device; and The relative position determination unit determines the relative position of the original's outline and creases based on the aforementioned image data. The above-mentioned original document reading unit has the following features: The first illumination unit illuminates the original document with light at the first incident angle; The second irradiation unit irradiates the original document with light at a second incident angle different from the first incident angle described above; and The light-receiving unit receives the light irradiated by the first irradiation unit and the second irradiation unit. The relative position determination unit extracts the creases and contours of the original document based on the first image data output by the light receiving unit receiving light from the first irradiation unit and the second image data output by the light receiving unit receiving light from the second irradiation unit.

2. The image forming apparatus according to claim 1, wherein, It also includes a decision unit that determines the correction amount of the setting value set in the post-processing device based on the relative position of the outline and crease of the original manuscript.

3. The image forming apparatus according to claim 2, wherein, It also has a notification unit, which notifies the aforementioned correction amount.

4. The image forming apparatus according to claim 2 or 3, wherein, It also includes a correction unit that corrects the setting value set in the post-processing device using the correction amount.

5. The image forming apparatus according to any one of claims 2 to 4, wherein, The unit of the above correction is length.

6. The image forming apparatus according to any one of claims 2 to 4, wherein, The units for the above corrections are ratios.

7. The image forming apparatus according to any one of claims 1 to 6, wherein, It also has: The image forming unit forms an image on the paper and outputs the original document; and The relative orientation acquisition unit acquires a relative orientation representing the relative orientation of the image relative to the original document based on the relative orientation of the paper and the image when the image forming unit outputs the original document.

8. A post-processing position adjustment method, which is performed by an image forming apparatus, wherein the image forming apparatus includes a post-processing device for folding a piece of paper on which an image is formed, wherein... The image forming apparatus described above also includes an original document reading unit for reading the original document. The above-mentioned original document reading unit has the following features: The first illumination unit illuminates the original document with light at the first incident angle; The second irradiation unit irradiates the original document with light at a second incident angle different from the first incident angle mentioned above; as well as The light-receiving unit receives the light irradiated by the first irradiation unit and the second irradiation unit. The above post-processing position adjustment methods include: The reading control step acquires image data output by the original document reading unit from a region, wherein the region includes the outline of the original document folded and creased by the post-processing device; and The relative position determination step involves determining the relative positions of the original artwork's outline and creases based on the aforementioned image data. In the aforementioned relative position determination step, the creases and contours of the original are extracted based on the first image data output by the light-receiving unit receiving light from the first irradiation unit and the second image data output by the light-receiving unit receiving light from the second irradiation unit.

9. A computer-readable recording medium recording a post-processing position adjustment program, wherein the post-processing position adjustment program is executed by a computer controlling an image forming apparatus, the image forming apparatus comprising a post-processing device for folding paper on which an image is formed, wherein... The image forming apparatus described above also includes an original document reading unit for reading the original document. The above-mentioned original document reading unit has the following features: The first illumination unit illuminates the original document with light at the first incident angle; The second irradiation unit irradiates the original document with light at a second incident angle different from the first incident angle described above; and The light-receiving unit receives the light irradiated by the first irradiation unit and the second irradiation unit. The above post-processing position adjustment procedure causes the above computer to execute: The reading control step acquires image data output by the original document reading unit from a region, wherein the region includes the outline of the original document folded and creased by the post-processing device; and The relative position determination step involves determining the relative positions of the original artwork's outline and creases based on the aforementioned image data. In the aforementioned relative position determination step, the creases and contours of the original are extracted based on the first image data output by the light-receiving unit receiving light from the first irradiation unit and the second image data output by the light-receiving unit receiving light from the second irradiation unit.

Images