JP2013067504A - Post-processing device, image forming/processing device having the same, and processing program - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a technique that can detect the defective folding of a recording medium bundle.SOLUTION: When a paper sheet P is conveyed while being folded by conveying rolls 27a, 27b, the conveying roll 27a is rotated by a normal feed length while the conveying roll 27b is rotated and then stopped. A torque is set so that though the paper sheet P which is longer than the normal length is held by the conveying roll 27a, the paper sheet P is not conveyed even if the conveying roll 27b is rotated when the conveying roll 27a is stopped while holding the paper sheet P. Therefore, the paper sheet P remains between the conveying rolls 27a and 27b. The presence or absence of the paper sheet P is confirmed by a sensor S2 to determine whether the defective folding is present or not.

Description

  The present invention relates to a post-processing apparatus, an image forming processing apparatus including the post-processing apparatus, and a processing program.

  As an example of performing post-processing on a sheet on which an image is formed by an image forming apparatus or the like, a booklet is produced by stacking a plurality of sheets and then performing saddle stitching or half-folding. Various techniques for detecting a folding failure are known.

  For example, Patent Document 1 discloses a technique for determining whether or not folding is good by using a paper feed length obtained from a paper passage time.

  For example, Patent Document 2 discloses a technique for detecting a folding failure using a line sensor.

  Further, for example, Patent Document 3 discloses a technique for detecting a folding failure using an ultrasonic transmitter and an ultrasonic receiver provided at positions sandwiching a paper conveyance path.

  For example, Patent Document 4 discloses a technique for detecting whether there is a shift by bringing a needle and a conductive member into contact with each other on the premise that there is a staple at a folding position.

  Further, for example, Patent Document 5 discloses a technique for detecting a position abnormality by arranging sensors at two locations on the paper side surface portion and at one location on the paper conveyance side reading portion.

  Further, for example, in Patent Document 6, the edge position of a signature being conveyed is measured a plurality of times by a sensor, the measured value is compared with a reference value, and the bending and signature of the signature are compared with the comparison data and threshold data. A technique for determining deviation is disclosed.

Japanese Patent Laid-Open No. 62-196249 JP-A-60-137770 JP 2008-222359 A JP 2005-112523 A JP-A-62-201752 JP-A-61-136868

  An object of the present invention is to provide a technique that can detect a folding failure of a bundle of recording media.

  In order to solve the above-described problem, the post-processing apparatus according to the first aspect of the present invention is provided with a storage unit that stores the recording medium bundle and a folding position of the recording medium bundle in the storage unit. Is provided in the rear stage of the first rotating means and the first rotating means stops when the recording medium bundle is held. The first rotating means is rotated by a preset rotation angle in a state in which the second rotating means that rotates due to the conveyance torque that does not convey the medium bundle and the second rotating means are rotated. Control means for executing control for stopping at a time point; first detection means for detecting the presence or absence of the recording medium bundle between the first and second rotation means after the first rotation means is stopped; After the first rotating means is stopped, the first inspection is performed. And having a determining means for determining the acceptability of the folded state in said recording medium bundle the information of the presence or absence of the detected said recording medium bundle by means.

  The post-processing apparatus according to a second aspect of the present invention is the post-processing apparatus according to the first aspect, wherein the preset rotation angle is a rotation corresponding to a feed length when the folded recording medium bundle is normally folded. The rotation angle of the recording medium bundle that is normally bent and passes through the recording medium holding position of the first rotation means, and the determination means is based on information from the first detection means. When it is determined that there is no recording medium bundle, it is determined that there is no middle folding defect, and when it is determined that there is a recording medium bundle, it is determined that there is a middle folding defect.

  A post-processing apparatus according to a third aspect of the present invention is the post-processing apparatus according to the first or second aspect, wherein the preset rotation is performed when a normal folding position of the recording medium bundle is deviated from the center. The angle is a rotation angle corresponding to a feed length shorter than a feed length at the time of normal folding of the folded recording medium bundle, and the determination means does not have the recording medium bundle based on information from the first detection means. If it is determined that the recording medium bundle is present, it is determined that there is no middle folding defect.

  The post-processing apparatus according to a fourth aspect of the present invention is the post-processing apparatus according to any one of the first to third aspects, wherein the control means determines that the recording medium bundle is present by the determination means. Thereafter, control for rotating both the first and second rotating means is executed.

  The post-processing apparatus according to a fifth aspect of the present invention is the recording medium according to any one of the first to fourth aspects, wherein the recording medium is pushed out by the extruding means before the first rotating means. A second detection means for detecting that the bundle has reached the rotation start position of the first and second rotation means is provided.

  The post-processing apparatus according to a sixth aspect of the present invention is the post-processing apparatus according to any one of the first to fifth aspects, wherein the control unit is configured to change the folding position of the recording medium bundle according to an amount of change. Control for changing the driving time of the first rotation driving means is executed.

  A post-processing apparatus according to a seventh aspect of the present invention is the post-processing apparatus according to any one of the first to sixth aspects, wherein the accommodating means changes the folding position by the pushing means. The control means sets a change amount of the folding position of the recording medium bundle based on the determination result by the determination means, and drives the folding position change means according to the change amount. Control for correcting a deviation in the folding position of the recording medium bundle by changing the folding position is performed.

  The image forming apparatus of the present invention described in claim 8 is provided in an image forming apparatus for forming an image on each of the recording medium bundles and an output stage of the image forming apparatus, and an image is formed by the image forming apparatus. The post-processing apparatus according to any one of claims 1 to 5, wherein the post-processing apparatus according to any one of claims 1 to 5 performs a middle folding process on the recorded recording medium bundle.

  According to a ninth aspect of the present invention, there is provided a processing program according to the present invention, wherein the recording medium bundle in the accommodating means is pushed out by the pushing means toward the first rotating means at the subsequent stage, and the recording medium reaches the first rotating means. Folding the bundle with the first rotating means, provided at the subsequent stage, and when the first rotating means stops in a state where the recording medium bundle is held, the recording medium bundle is not conveyed. A control process of stopping when the first rotating means is rotated by a preset rotation angle in a state where the second rotating means is rotated when transported to the rotating second rotating means; A detection process for detecting the presence or absence of the recording medium bundle between the first and second rotating means after stopping the first rotating means, and the first rotating means after stopping the first rotating means. Before being detected by the detection means Characterized in that to execute a determination process of determining the acceptability in folded state of the recording medium bundle the information of the presence or absence of the recording medium bundle, to the computer.

  According to a tenth aspect of the present invention, there is provided the processing program according to the seventh aspect, wherein the preset rotation angle is a rotation angle corresponding to a feed length when the folded recording medium bundle is normally folded. And the rotation angle is such that the normally folded recording medium bundle passes through the recording medium holding position of the first rotating means, and the determination means determines that the recording medium bundle is not present in the pre-detection process. If it is determined, it is determined that there is no middle folding defect, and if it is determined that the recording medium bundle is present, it is determined that there is a middle folding defect.

  According to an eleventh aspect of the present invention, there is provided the processing program of the present invention according to the seventh or eighth aspect, wherein the preset rotation angle is set when the regular folding position of the recording medium bundle is deviated from the center. Is a rotation angle corresponding to the feed length shorter than the feed length at the time of normal folding of the folded recording medium bundle, and the determination means determines that the recording medium bundle is not folded when the detection process determines that there is no recording medium bundle. If it is determined that there is a defect, and it is determined that the recording medium bundle is present, it is determined that there is no middle folding defect.

  According to the first aspect of the present invention, it is possible to detect an intermediate folding failure of the recording medium bundle.

  According to the second aspect of the present invention, it is possible to detect a middle folding failure when the length of the folded recording medium bundle is longer than that during normal folding.

  According to the third aspect of the present invention, it is possible to detect the middle folding failure of the recording medium bundle even when the normal folding position of the recording medium bundle is shifted from the center.

  According to the fourth aspect of the present invention, it is possible to detect the clogging defect of the recording medium bundle.

  According to the fifth aspect of the present invention, it is possible to improve the accuracy of detecting the middle folding failure of the recording medium bundle.

  According to the sixth aspect of the present invention, even when the normal folding position of the recording medium bundle is shifted from the center, it is possible to improve the detection accuracy of the middle folding failure of the recording medium bundle.

  According to the invention described in claim 7, it is possible to correct the folding position deviation of the recording medium bundle.

  According to the eighth aspect of the present invention, it is possible to detect the middle folding failure of the recording medium bundle in the post-processing apparatus of the image forming processing apparatus.

  According to the ninth aspect of the present invention, it is possible to detect the middle folding failure of the recording medium bundle.

  According to the tenth aspect of the present invention, it is possible to detect an intermediate folding failure when the feeding length of the folded recording medium bundle is longer than that during normal folding.

  According to the eleventh aspect of the present invention, even when the normal folding position of the recording medium bundle is shifted from the center, it is possible to detect the middle folding failure of the recording medium bundle.

1 is a configuration diagram of an image forming processing apparatus to which a post-processing apparatus according to a first embodiment of the present invention is applied. It is the block diagram which expanded and showed the middle folding process part of the middle folding processing apparatus of FIG. It is the block diagram which expanded and showed the conveyance path of the middle folding processing apparatus of FIG. It is a block diagram of the circuit block of the post-processing apparatus of FIG. It is a top view of the paper before half-folding. FIG. 6 is a perspective view of a sheet when the sheet of FIG. 5 is folded in half. FIG. 6 is a perspective view of a sheet when a folding position is shifted from a center line. FIG. 6 is a plan view of a sheet when skew deviation occurs. It is explanatory drawing of the middle folding process in the middle folding processing apparatus of FIG. It is explanatory drawing of the middle folding defect detection process in the middle folding processing apparatus of FIG. FIG. 11 is an explanatory diagram of a middle folding defect detection step subsequent to FIG. 10. It is explanatory drawing of the middle fold defect detection process in the middle fold processing apparatus of FIG. FIG. 13 is an explanatory diagram of a middle folding defect detection step subsequent to FIG. 12. FIG. 10 is an explanatory diagram when a paper jam has occurred in a conveyance path of a half-fold processing apparatus. It is explanatory drawing of the detection process of the middle folding defect and paper jam defect in the middle folding processing apparatus of the post-processing apparatus which concerns on the 2nd Embodiment of this invention. It is explanatory drawing of the detection process of the middle folding defect and paper jam defect in the middle folding processing apparatus of the post-processing apparatus which concerns on the 2nd Embodiment of this invention. It is a figure of the flowchart of the middle folding process in the middle folding processing apparatus of the post-processing apparatus which concerns on the 3rd Embodiment of this invention. It is explanatory drawing of the middle folding process by the middle folding processing apparatus of the post-processing apparatus of the 3rd Embodiment of this invention. It is explanatory drawing of the middle folding defect detection process in the middle folding processing apparatus of the post-processing apparatus which concerns on the 3rd Embodiment of this invention. FIG. 20 is an explanatory diagram of a middle folding defect detection step subsequent to FIG. 19. FIG. 21 is an explanatory diagram of a middle folding defect detection step subsequent to FIG. 20. It is explanatory drawing of the middle folding defect detection process in the middle folding processing apparatus of the post-processing apparatus which concerns on the 3rd Embodiment of this invention. FIG. 23 is an explanatory diagram of a middle folding defect detection step subsequent to FIG. 22. FIG. 24 is an explanatory diagram of a middle folding defect detection step subsequent to FIG. 23. FIG. 23 is an explanatory diagram of a middle folding defect detection step subsequent to FIG. 22. FIG. 26 is an explanatory diagram of a middle folding defect detection step subsequent to FIG. 25.

  Hereinafter, an embodiment as an example of the present invention will be described in detail with reference to the drawings. Note that components having the same function are denoted by the same reference symbols throughout the drawings for describing the embodiment, and the repetitive description thereof will be omitted.

  (First embodiment)

  FIG. 1 is a configuration diagram of an image forming processing apparatus to which a post-processing apparatus according to an embodiment of the present invention is applied.

  An image forming processing apparatus 1 according to the present embodiment includes an image forming apparatus 2 that forms an image on a sheet (an example of a recording medium), and a plurality of post-processing apparatuses 3 that are installed in a subsequent stage and perform post-processing on the sheet. , 4 and 5.

  The image forming apparatus 2 includes, for example, a digital copying machine, a digital printer, or a multifunction machine having both functions, and has a single-sided printing function for printing on one side of paper and a double-sided printing function for printing on both sides of paper. . The image transfer method of the image forming apparatus 2 may be, for example, a direct transfer method in which the toner image on the photosensitive drum is transferred to a sheet, and the toner image transferred on the intermediate transfer belt is transferred to the intermediate transfer belt. An intermediate transfer method for transferring an image onto a sheet may be used.

  The post-processing apparatus 3 has a function of waiting for a plurality of sheets discharged from the image forming apparatus 2 and a function of conveying the sheets to the post-processing apparatus 4 in the subsequent stage at a predetermined timing. ing.

  The post-processing device 4 has a function of performing additional processes such as a binding process, a punching process, and a half-folding process on the paper sent from the post-processing apparatus 3. At the entrance of the post-processing device 4, a transport roll 8 that receives the paper sent from the post-processing device 3 and carries it into the post-processing device 4 is provided. A puncher 9 for punching paper is provided immediately after the transport roll 8.

  The sheet conveyance path downstream of the puncher 9 is branched into two, an upper conveyance path 10 and a lower conveyance path 11. The upper conveyance path 10 is further divided into two conveyance paths 10a and 10b. One conveyance path 10 a is a conveyance path that guides the sheet to the paper discharge unit 12 a at the top of the post-processing device 4. The other conveyance path 10 b is a conveyance path that guides the sheet to the paper discharge unit 12 b on the side surface of the post-processing device 4, and the end of the sheet is bound by the stapler 13 in the middle. The transport member 14 with a paddle and the tamper 15 provided in the middle of the transport path 10b have a function of transporting a plurality of sheets guided to the transport path 10b back to the stapler 13 with their rear ends aligned. . The paper discharge unit 12b is a so-called offset catch tray that moves up and down along the side surface of the post-processing device 4, and automatically descends as the number of sheets to be discharged increases. Yes.

  On the other hand, the conveyance path 11 below the puncher 9 is a conveyance path that guides the sheet to the half-folding processing device 18. A conveyance path 19 behind the conveyance paths 10 and 11 is a conveyance path that reverses the sheet and guides it to the half-folding processing device 18. A common path on the lower end side of the conveyance paths 11 and 19 is provided with a conveyance member 21 with a paddle that guides the sheet sent to the conveyance paths 11 and 19 to a tray (an example of a storage unit) 20 of the half-folding processing device 18. ing. In the conveyance paths 10, 10 a, 10 b, 11, and 19, conveyance members (conveyance rolls, guide rails, and the like) for conveying paper are arranged.

  The half-folding processing device 18 is a device for making a plurality of sheets into a booklet. The tray 20 of the center folding processing device 18 has a function of storing and aligning a plurality of sheets sent from the transport paths 11 and 19. The tray 20 is provided in an inclined state, and an end guide (folding position change) for setting a lower end position (a front end position in the sheet traveling direction) of a plurality of sheets to a predetermined position at a lower end thereof. Means) 20a is provided so as to be movable up and down. The end guide 20a is moved up and down by, for example, a pulse motor (not shown).

  Further, in the vicinity of the end guide 20a, a transport member 20b with a paddle for aligning a plurality of sheets in the tray 20 is provided. Further, a tamper (not shown) is provided at the upper end of the tray 20 to align the positions in the width direction of a plurality of sheets in the tray 20.

  Further, the saddle folding processing device 18 is provided with a saddle stapler 22 for performing saddle stitching processing on a plurality of sheets aligned on the tray 20. On the back side of the tray 20 above the saddle stapler 22, a folding knife (an example of an extruding means) 25 is provided.

  The folding knife 25 is a member that folds a plurality of sheets P in the tray 20 at a preset folding position. In the subsequent stage, the bundle of sheets pushed out by the folding knife 25 is conveyed by the post-processing device 5. A conveyance path 26 is provided to send to the processing unit 5a. In this conveyance path 26, three conveyance rolls 27a, 27b, and 28 are sequentially arranged along the sheet conveyance direction. The folding knife 25 and the transport rolls 27a and 27b will be described in detail later.

  The conveyance processing unit 5a of the post-processing device 5 transfers the booklet to the post-processing device 5 while correcting the skew so that the back of the bundle of sheets (booklet) sent from the center folding processing device 18 is aligned with a predetermined position. It is a mechanism part to convey. The post-processing device 5 has a square fold processing function for forming the back portion of the booklet processed by the post-processing device 4 into a square shape, and a trimmer processing function for cutting to adjust the small edge shape of the booklet after the square folding processing. The booklet whose appearance is adjusted by the post-processing device 5 is accommodated in the booklet accommodating portion 5b at the rear end.

  Next, the intermediate folding processing unit 18 will be described in detail with reference to FIGS. 2 and 3. FIG. 2 is an enlarged configuration diagram illustrating the middle folding processing unit 18 of FIG. 1, and FIG. 3 is an enlarged configuration diagram illustrating the conveyance path 26 of the middle folding processing device 18 of FIG. 1. . 2 indicates the conveyance direction of the paper P, and the arrow R in FIGS. 2 and 3 indicates the rotation direction of the conveyance rolls 27a and 27b.

  As shown in FIG. 2, the folding knife 25 is provided so as to be able to advance to a position opposed to a pair of transport rollers (an example of the first rotating means) 27 a in the subsequent stage through a hole 30 whose tip passes through the front and back surfaces of the tray 20. It has been. That is, the plurality of sheets P in the tray 20 are folded inward by advancing the folding knife 25 toward the transporting roll 27a, and between the pair of transporting rolls 27a and 27a with the folded back part at the top. Extruded.

  The pair of transport rolls 27a and 27a is transported between the pair of transport rolls (second rotating means) 27b and 27b through the transport path 26 while winding and folding the bundle of sheets P pushed between them. It has become. Further, the pair of transport rolls 27b and 27b transports the bundle of sheets P transported between them through the transport path 26 between the pair of subsequent transport rolls 28 and 28 (see FIG. 1). Yes.

  As shown in FIG. 3, the front and rear transport rolls 27a and 27b are arranged such that the front end of the bundle of folded paper P is the rear stage before the rear end of the bundle of folded paper P passes through the front stage transport roll 27a. When the bundle of folded paper P reaches the conveyance roll 27b and the bundle of folded sheets P has passed the sheet holding position (hereinafter referred to as the nip position) of the preceding conveyance roll 27a, the bundle of folded sheets P is transferred to the conveyance roller 27b at the subsequent stage. It is set to be interposed between the pair. These transport rolls 27a and 27b are rotated by motors M1 and M2, respectively. The motors M1 and M2 are, for example, pulse motors, and are set so that the sheet conveyance distance per pulse becomes a predetermined length.

  Further, in the present embodiment, the front and rear transport rolls 27a and 27b are configured so that the bundle of folded paper P is transported to the subsequent stage when the preceding transport roll 27a is stopped while holding the folded bundle of paper P. Even if the transport roll 27b rotates while reaching the roll 27b, the folded bundle of sheets P is set to have a transport torque relationship that is not transported to the subsequent stage of the transport roll 27b. Although there is no particular limitation on the relationship between the conveyance torques, a torque limiter may be provided on the conveyance roller 27b at the subsequent stage.

  Further, in the transport path 26, a sensor S1 is installed in the vicinity of the preceding stage of the preceding transport roll 27a. This sensor S1 is a front roll for more accurately detecting that the bundle of folded paper P pushed out by the folding knife 25 has reached the distance Y from the paper winding start position of the front transport roll 27a. It is a detection means for carrying-in detection. When the paper P is detected by the sensor S1, the transport rolls 27a and 27b start to rotate. In the present embodiment, as will be described later, the folded sheet P is stopped when the preceding transport roll 27a is rotated by an amount necessary to pass the nip position of the transport roll 27a. Be controlled. For example, assuming that the length of the folded paper P is L and the transport distance per pulse of the motor M1 is Z, the motor M1 turns on the sensor S1 after the bundle of folded paper P is carried in (L + Y). Control is made to stop at the point of rotation by the amount of / Z pulse output. For this reason, it is necessary to more accurately recognize the timing at which a bundle of folded sheets P is carried into the transport roll 27a.

  Further, in the transport path 26, a sensor S2 is installed in the vicinity of the front stage of the rear stage transport roll 27b. This sensor S2 is a detection means for detecting a remaining sheet for detecting whether or not a bundle of folded sheets P exists between the front and rear transport rollers 27a and 27b. As these sensors S1 and S2, for example, optical sensors are used.

  Next, FIG. 4 is a block diagram of the circuit block of the post-processing device 4 in FIG. A CPU (Central Processing Unit: control means, determination means) is a control unit that controls the overall operation of the post-processing device 4, and is electrically connected to the motors M1 to M3, the sensors S1 and S2, and the storage means ME. Yes. The motor M3 is a pulse motor or the like for vertically moving the end guide 20a (see FIG. 1).

  The storage unit ME is formed of a storage medium such as a hard disk, for example, and includes, for example, a sheet feed length, a folded sheet feed length theoretical value, a sheet transport distance per pulse, a distance from the sensor S1 to the transport roll 27a, the number of output pulses, The amount of movement of the tray 20 (the amount of vertical movement of the end guide 20a), the amount of folding position change (shift) when the folding position is intentionally shifted from the center of the sheet, the one-way deviation allowable amount, and the correction amount are stored.

  Next, FIGS. 5 to 8 show changes in the feed length due to the misalignment of the folding position of the paper P. FIG. FIG. 5 is a plan view of the paper P before being folded. Let X be the length of the long side of the paper P. FIG. 6 is a perspective view of the paper P when the paper P of FIG. 5 is folded in half. In this case, the paper feed length is X / 2.

  On the other hand, FIG. 7 is a perspective view of the paper P when the folding position is deviated from the center line K. FIG. In this case, the paper feed length is X / 2 + α. FIG. 8 is a plan view of the paper P in the case where a skew deviation has occurred. The paper P is folded in a state shifted asymmetrically. A broken line indicates a sheet P that is normally folded in half for comparison. In this case, the feed length is X / 2 + β. That is, it can be seen that when the folding position is deviated unexpectedly (FIGS. 7 and 8), the feeding length is longer than when the folding position is normally folded in half (FIG. 6). This is used in the present embodiment.

  Next, a specific example of the detection method of the middle folding failure of the sheet in the middle folding processing device 18 of the post-processing device 4 of the present embodiment will be described with reference to FIGS. 9 is an explanatory diagram of the middle folding processing in the middle folding processing device 18 in FIG. 1, and FIGS. 10 and 11 are explanatory diagrams of the middle folding failure detection process in the middle folding processing device 18 in the case where folding deviation has not occurred. 12 and 13 are explanatory diagrams of the process of detecting a middle fold failure in the middle fold processing device 18 in the case of occurrence of fold misalignment.

  Here, as shown in FIG. 9, a case where a plurality of sheets P are folded in half will be described. First, the knife 25 is pushed out to the pair of transport rolls 27a through the plurality of sheets P in a state where the knife 25 is installed at the center in the longitudinal direction of the plurality of sheets P in the tray 20. When the knife 25 detects a sensor S1 shown in FIG. 10 in the process of pushing a plurality of sheets P toward the preceding transport roll 27a, the transport rolls 27a and 27b rotate to fold the plurality of sheets P. Transport while.

  At this time, in the present embodiment, while the rear-stage transport roll 27b is rotated, the front-stage transport roll 27a is rotated by the length (X / 2 + Y) when the folded bundle of sheets P is normally folded. Stop at the point. In other words, the transport roller 27a is stopped when the transport roller 27a at the previous stage is rotated by the amount that the bundle of the normally folded sheets P passes through the nip position of the transport roller 27a. Specifically, in the same manner as described with reference to FIG. 3, after the sensor S1 is turned on by the bundle of folded sheets P, the motor M1 is stopped when the motor M1 is rotated by the amount of (X / 2 + Y) / Z pulse output. Let

  At this time, if the bundle of sheets P has no middle folding failure, the bundle of sheets P passes through the nip position of the preceding transport roll 27a and is not held by the preceding transport roll 27a, as shown in FIG. In addition, the bundle of sheets P that has been folded by the rotation of the subsequent transport roll 27b is transported to the subsequent stage of the transport roll 27b.

  Thereafter, whether or not there is a bundle of sheets P between the transport rollers 27a and 27b is confirmed by the sensor S2. Here, since the folded sheet P is not present between the transport rolls 27a and 27b, it is determined that there is no middle folding defect.

  On the other hand, when there is a folding shift, the length of the folded paper P is longer than that in the normal case, as described above with reference to FIGS. For this reason, as described above, the length of the bundle of sheets P that has been folded in the preceding conveyance roll 27a is equal to the length (X / 2 + Y) when the bundle of sheets P is normally folded. When the rotation is stopped at the point of rotation (as much as it passes through the position), as shown in FIG. 12, the rear end of the bundle of sheets P is sandwiched and held by the nip position of the front-stage transport roll 27a, and the transport roll 27a Will stop.

  Here, as described above, the front and rear transport rolls 27a and 27b are configured so that the bundle of folded paper P is transported to the subsequent stage when the previous transport roll 27a is stopped in a state where the folded bundle of paper P is held. Even when the transport roll 27b rotates while reaching the roll 27b, a set of transport torques is set so that a bundle of folded sheets P is not transported to the subsequent stage. For this reason, as shown in FIG. 13, when the transport roller 27b in the previous stage is rotated with the transport roller 27a in the previous stage stopped, the bundle of sheets P is not transported and remains between the transport rolls 27a and 27b. .

  Thereafter, it is confirmed by the sensor S2 whether or not there is a bundle of sheets P between the transport rolls 27a and 27b. Here, since the folded sheet P is between the transport rolls 27a and 27b, there is a middle folding defect. To be judged.

  As described above, in the present embodiment, the middle folding failure of the bundle of folded sheets P is reliably detected. Further, since the detection accuracy of the middle folding defect depends on the conveyance distance per pulse of the conveyance roll 27a, the middle folding defect is detected with high accuracy. Further, the sensors S1 and S2 provided for detecting the middle folding failure are inexpensive because they are simply turned on and off and do not require high accuracy, and the cost of the post-processing device 4 just because they are provided. Will not be significantly higher.

  (Second Embodiment)

  FIG. 14 is an explanatory diagram of a conveyance path when a paper jam occurs in the middle folding processing apparatus of the second embodiment of the post-processing apparatus, and FIGS. 15 and 16 illustrate middle folding failure and middle folding in the middle folding processing apparatus. FIG. 10 is an explanatory diagram of a paper jam defect detection process.

  In the first embodiment, the center P is detected by detecting the bundle of sheets P by the sensor S2. However, as shown in FIG. 14, even when there is a paper jam at the rear stage of the transport roll 27b. Since the bundle of the sheets P is detected by the sensor S2, it is not possible to discriminate between the middle folding failure and the paper jam failure only by the detection by the sensor S2.

  Thus, in the second embodiment, as described above, when the bundle of sheets P is detected by the sensor S2 after the rotation and stop of the preceding transport roll 27a, the previous transport roll 27b is rotated and the previous transport roll 27b is rotated. The rotation of the roll 27a is resumed. Thereafter, as shown in FIG. 15, when a bundle of sheets P is detected by the sensor S2, it is determined that a paper jam has occurred.

  On the other hand, as shown in FIG. 16, when the bundle of the sheets P is not detected by the sensor S2, it is determined that there is no paper jam and it is determined that there is a middle folding failure.

  In this way, in the second embodiment, it is well determined whether the remaining sheet detected by the sensor S2 is caused by a middle folding failure of the paper P or a paper jam.

  (Third embodiment)

  In the third embodiment, when the regular folding position of the paper is shifted from the position of dividing the paper into two equal parts, the middle folding of the folded paper is performed while the same middle folding operation is continuously performed. A method for verifying the defect and correcting the folding position deviation by automatically adjusting the position of the folding knife (the amount of movement of the paper storage tray) will be described.

  FIG. 17 is a flowchart of the middle folding process of the third embodiment, and FIG. 18 is an explanatory diagram of the middle folding process by the middle folding apparatus of the post-processing apparatus of the third embodiment.

  First, the middle folding operation is started (step 100). Here, as shown in FIG. 18, the end guide 20a of the tray 20 is lowered by .alpha. From the case of FIG. Shift from the center. For this reason, the length in the feeding direction of the folded paper P is X / 2 + α during normal folding. In the following description, the number of pulses corresponding to the distance (X / 2 + α + Y) corresponding to the folded sheet feed length is A, the unidirectional deviation allowable number of pulses is B, and the number of correction pulses is C.

  Subsequently, as in the first embodiment, the paper P is conveyed while being folded by rotating the conveyance rolls 27a and 27b. Here, (A-B) pulses are output from the motor M1 to the preceding transport roll 27a. That is, while the subsequent transport roll 27b is rotated, the front transport roll 27a is stopped when it is rotated by an amount shorter than the normal length (X / 2 + α + Y) after the bundle of sheets P is folded. That is, it stops when the transport roll 27a of the previous stage is rotated so that the bundle of the normally folded sheets P is held without passing through the nip position of the transport roll 27a (step 101).

  Thereafter, similarly to the first embodiment, it is determined whether or not a bundle of sheets P is left between the transport rolls 27a and 27b by the sensor S2 (see FIG. 3 and the like) (step 102). In this case, since the feed length of the paper P by the transport roller 27a in the previous stage is shorter than the length in which the bundle of paper P passes through the nip position, if the bundle of paper P is transported to the subsequent stage without being detected. The bundle of sheets P is too short and is not allowed to be corrected. Therefore, the user is informed that the defect is not acceptable for correction (step 103).

  On the other hand, if a bundle of sheets P is detected in step 102, the folded sheet P is additionally conveyed by outputting a (B × 2) pulse to the preceding conveyance roll 27a (step 104). Here, the same margin is provided in both the front and rear directions of the paper P. This process confirms whether the folded sheet P is within the allowable range of the correction process.

  Subsequently, it is determined whether or not the folded sheet P can be conveyed (step 105). If the sheet cannot be conveyed, the bundle of folded sheets P is too long to be out of correction allowance, and the user is notified that the defect is out of correction allowance (step 103). That is, in step 103, if the feed length of the folded paper P has a deviation of ± B pulses or more from the theoretical value, the user is prompted for intervention without correction.

  On the other hand, if it is possible to transport the bundle of folded sheets P in step 105, it is determined that the feed length of the folded sheets P is within the correction tolerance, and the process proceeds to the step on the right side of FIG. Hereinafter, the middle folding defect detection step of the third embodiment will be described along the flow of FIG. 17 with reference to FIGS. FIGS. 19 to 26 are explanatory views of the middle folding defect detection step.

  First, the middle folding operation is started (step 200), and the sheet P is conveyed while being folded by rotating the conveying rolls 27a and 27b as shown in FIG. 19, as in the first embodiment. Here, an A pulse is output from the motor M1 to the preceding transport roll 27a. That is, while the rear-stage transport roll 27b is rotated, the length of the bundle of sheets P that have been folded at the front-stage transport roll 27a (X / 2 + α + Y) (the bundle of sheets P that are normally folded) is folded. Is stopped when it is rotated (by the amount that passes through the nip position of the transport roll 27a) (step 201). In this case, the rotation driving time of the transport roll 27a is made longer by α than in the case of the first embodiment.

  Here, when the length of the folded paper P in the feeding direction is equal to or shorter than the desired value, as shown in FIG. 20, the folded paper P passes through the nip position of the preceding transport roll 27a. As shown in FIG. 21, the sheet is further conveyed to the subsequent stage by the subsequent conveyance roll 27b. Accordingly, since the folded sheet P is not detected between the transporting rolls 27a and 27b in the subsequent detection step by the sensor S2, it is determined that there is no middle folding defect (step 202).

  Here, when the paper P is divided into two equal parts as in the first embodiment, if it is determined that there is no middle folding defect, the folding position misalignment (middle folding fault) of the folded paper P is also caused. Absent. However, when the regular folding position is shifted from the center of the paper P as in the third embodiment, even if it is determined that there is no middle folding defect, the folding position is shifted, and the paper P In some cases, the length in the feed direction is shorter than the desired value.

  Therefore, in the third embodiment, even when it is determined in step 202 that there is no remaining sheet, whether or not the length of the folded sheet P is shorter than the desired value is also verified.

  First, the middle folding operation is started (step 300), and the sheet P is conveyed while being folded by rotating the conveying rolls 27a and 27b as shown in FIG. 22 as in the first embodiment. Here, (A−C) pulses are output from the motor M1 to the transport roller 27a at the previous stage. That is, while the rear-stage transport roll 27b is rotated, the front-stage transport roll 27a is shorter than the regular length (X / 2 + α + Y) after the bundle of sheets P is folded (a bundle of sheets P that are normally folded). Is rotated and stopped (step 301). In this case, the rotation driving time of the transport roll 27a is set longer than that in the first embodiment and shorter than that in step 201. As the rotation driving time of the transport roll 27a is shortened, the detection accuracy of the middle folding defect (positional deviation defect) is improved.

  Here, when the length of the folded paper P in the feeding direction is a desired value, as shown in FIG. 23, the folded paper P is held at the nip position of the transport roll 27a. Thus, it is left between the transport rolls 27a and 27b. Accordingly, in the subsequent detection step by the sensor S2, the folded paper P is detected between the transport rollers 27a and 27b (step 302), and the length of the folded paper P is determined to be a desired value. . In this case, after that, the conveyance rolls 27a and 27b are rotated to additionally convey the folded paper P (step 303), and the process ends.

  On the other hand, if the feed length of the folded paper P is shorter than the desired value after step 301, as shown in FIG. 25, the folded paper P is not held on the preceding transport roll 27a. As shown, the sheet is further conveyed to the subsequent stage by the subsequent-stage conveyance roll 27b. Accordingly, since the folded sheet P is not detected between the transport rollers 27a and 27b in the subsequent detection process by the sensor S2 (step 302), it is determined that the length of the folded sheet P is shorter than the desired value. The In this case, after that, the amount of movement of the end guide 20a of the tray 20 is added by the amount corresponding to the C pulse to increase the folded sheet feed length (step 304), and the same verification is performed by returning to step 300.

  On the other hand, when the folded sheet P is detected between the transport rolls 27a and 27b in the step 202 and the middle folding failure is detected, the length of the folded sheet P is longer than the desired value. The amount of movement of the end guide 20a of the tray 20 is subtracted by C pulses to shorten the folded paper feed length (step 400), and the process proceeds to steps 401 to 403. Since Steps 401 to 403 are the same as Steps 200 to 202, description thereof will be omitted.

  If a bundle of paper P is detected between the transport rolls 27a and 27b in step 403, the transport rolls 27a and 27b are rotated to carry the folded paper P further (step 404), and then return to step 400. The same verification is performed by changing the correction value. On the other hand, if a bundle of sheets P is not detected between the transport rolls 27a and 27b in step 403, the process ends.

  As described above, in the third embodiment, even when the normal folding position is shifted from the position where the paper P is divided into two equal parts, the middle folding failure of the bundle of the folded paper P is reliably detected.

  Further, during the same middle folding operation, the length of the folded paper P in the paper feeding direction is verified, and the position of the folding knife 25 (the amount of movement of the end guide 20a) is automatically set. To correct the misalignment of the folding position.

  Although the invention made by the present inventor has been specifically described based on the embodiment, the embodiment disclosed in this specification is an example in all respects and is limited to the disclosed technology. Should not be considered. That is, the technical scope of the present invention should not be construed restrictively based on the description in the above-described embodiment, but should be construed according to the description of the scope of claims. All modifications are included without departing from the technical scope equivalent to the described technique and the gist of the claims.

  For example, the case where the present invention is applied to an image forming apparatus that records toner is shown, but the present invention may be applied to, for example, an (inkjet type image forming apparatus that records with ejected ink).

  When using a program, it may be provided via a network or stored in a recording medium such as a CD-ROM.

  That is, the present invention is not limited to the case where the program composed of steps 100 to 105, 200 to 202, 300 to 304, 400 to 404, etc. is recorded in a storage device such as a hard disk, but may be provided as follows. Good.

  For example, the program may be stored in the ROM, and the CPU may load the program from the ROM to the main storage device and execute it.

  The program may be stored and distributed in a computer-readable storage medium such as a DVD-ROM, CD-ROM, MO (magneto-optical disk), or flexible disk.

  Further, the image forming processing apparatus or the like is connected to the server apparatus or the host computer via a communication line (for example, the Internet), and the program is downloaded after the program is downloaded from the server apparatus or the host computer. Also good. In this case, examples of the download destination of the program include a memory such as a RAM and a storage device (storage medium) such as a hard disk.

  In the above description, various media on which an image is formed, such as a film and a postcard, are applied as the recording medium conveyed in the post-processing apparatus of the present invention.

DESCRIPTION OF SYMBOLS 1 Image formation processing apparatus 2 Image forming apparatus 4 Post-processing apparatus 18 Middle folding processing apparatus 20 Tray 20a End guide 20b Conveying member 25 with a paddle 26 Folding knife 26 Conveyance path 27a, 27b, 28 Conveyance roll 30 Hole M1, M2, M3 Motor ME Storage means S1, S2 Sensor P Paper

Claims (11)

Storage means for storing the recording medium bundle;
An extrusion means provided at a folding position of the recording medium bundle in the accommodating means, and for extruding the recording medium bundle toward the first rotating means in the subsequent stage;
A second rotation provided at a stage subsequent to the first rotating means and rotating in relation to a conveying torque at which the recording medium bundle is not conveyed when the first rotating means is stopped while holding the recording medium bundle; Means,
Control means for executing control to stop the first rotating means at a time when the first rotating means is rotated by a preset rotation angle with the second rotating means rotated;
First detecting means for detecting the presence or absence of the recording medium bundle between the first and second rotating means after stopping the first rotating means;
Determining means for determining whether the folded state of the recording medium bundle is good or not based on information on the presence or absence of the recording medium bundle detected by the first detecting means after the first rotating means is stopped;
A post-processing apparatus comprising: The preset rotation angle is a rotation angle corresponding to the feed length at the time of normal folding of the folded recording medium bundle, and the normally folded recording medium bundle is held by the first rotating means as the recording medium. The rotation angle for passing the position,
The determination unit determines that there is no half-fold failure when it is determined that the recording medium bundle is not present based on the information from the first detection unit, and if the determination unit determines that the recording medium bundle is present, the middle-fold failure is The post-processing device according to claim 1, wherein the post-processing device is determined to be present. When the regular folding position of the recording medium bundle is deviated from the center, the preset rotation angle is a rotation angle corresponding to a feeding length shorter than the feeding length at the time of regular folding of the folded recording medium bundle. And
The determination unit determines that there is a middle folding defect when it is determined that the recording medium bundle is not present based on information from the first detection unit, and determines that there is a middle folding defect when the recording medium bundle is present. The post-processing apparatus according to claim 1, wherein it is determined that there is no post-processing apparatus.   4. The control unit according to claim 1, wherein the control unit executes control to rotate both the first and second rotation units after the determination unit determines that the recording medium bundle is present. The post-processing apparatus of any one of Claims.   A second detection means for detecting that the recording medium bundle pushed out by the pushing means has reached the rotation start position of the first and second turning means is provided in the preceding stage of the first rotating means. The post-processing apparatus according to any one of claims 1 to 4, wherein   6. The control unit according to claim 1, wherein the control unit executes control for changing a driving time of the first rotation driving unit according to a change amount of the folding position of the recording medium bundle. The post-processing apparatus as described in a term. The accommodating means includes a folding position changing means for changing the folding position by the pushing means,
The control unit sets a change amount of the folding position of the recording medium bundle based on a determination result by the determination unit, and changes the folding position by driving the folding position changing unit according to the change amount. The post-processing apparatus according to claim 1, wherein control for correcting a deviation of the folding position of the recording medium bundle is executed.   An image forming apparatus that forms an image on each of the recording medium bundles, and a recording medium bundle that is provided at an output stage of the image forming apparatus and on which an image is formed by the image forming apparatus, is subjected to a middle folding process. An image forming processing apparatus comprising: the post-processing apparatus according to any one of 1 to 7. A process of extruding the recording medium bundle in the storage means toward the first rotating means at the subsequent stage by the pushing means;
The recording medium bundle that has reached the first rotating means is provided at the subsequent stage while being folded by the first rotating means, and the first rotating means is stopped when holding the recording medium bundle. When the recording medium bundle is transported to a second rotating means that rotates due to a transport torque that is not transported, the first rotating means is rotated in a preset state while the second rotating means is rotated. A control process that stops when the angle is rotated;
A detection process for detecting the presence or absence of the recording medium bundle between the first and second rotating means after the first rotating means is stopped;
A determination process of determining whether the folded state of the recording medium bundle is good or not based on information on the presence / absence of the recording medium bundle detected by the first detecting means after the first rotating means is stopped;
A processing program for causing a computer to execute. The preset rotation angle is a rotation angle corresponding to the feed length at the time of normal folding of the folded recording medium bundle, and the normally folded recording medium bundle is held by the first rotating means as the recording medium. The rotation angle for passing the position,
The determination means determines that there is no half-fold failure when it is determined that there is no recording medium bundle in the previous detection process, and determines that there is a middle folding failure when it is determined that the recording medium bundle exists. 10. The processing program according to claim 9, wherein When the regular folding position of the recording medium bundle is deviated from the center, the preset rotation angle is a rotation angle corresponding to a feeding length shorter than the feeding length at the time of regular folding of the folded recording medium bundle. And
The determining means determines that there is a middle folding defect when it is determined that the recording medium bundle is not present by the detection process, and determines that there is no middle folding defect when it is determined that the recording medium bundle is present. The processing program according to claim 9 or 10, characterized in that the processing program.