JP2007001700A - Sheet treatment device and image formation system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To perform simply and accurately a skew correction of paper sheets even after a folding process is conducted. <P>SOLUTION: The arrangement according to the invention comprises at least one set of first conveyance rollers for holding and conveying each sheet on a conveying route, at least one set of second conveyance rollers for holding and conveying the sheet in the downstream of the first conveyance rollers on the conveying route, a sheet conveying means to rotate the first and the second conveyance rollers for conveying the sheet in the conveying direction directed from upstream in the conveying route to the downstream, and a sheet skew correcting means to stop the first conveyance roller rotating after the sheet has passed it and reverse the second conveyance roller for retreating the sheet in the opposite direction to conveyance and to abut the rear edge of the sheet to the hold position of the first conveyance roller which stopped rotation, and thereby perform the rear edge aligning process for correcting the skew with respect to the sheet conveying direction. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a sheet processing apparatus that performs processing such as binding, punching, and stamping on a sheet, and an image forming system such as a copying machine, a printer, a facsimile, and a printing machine in which the sheet is integrated or attached.

  Sorting, binding, punching for filing, stamping, adding information, etc. to paper on which images are formed by image forming devices such as copiers, printers, and facsimiles Various paper processing apparatuses that perform the above processing have been provided.

JP-A-8-81089 JP 2002-160848 A

  However, in general, the paper discharged from the image forming apparatus is often inclined (hereinafter also referred to as skew) with respect to the conveyance direction. This causes a problem that the accuracy of processing deteriorates due to the influence of the above. Therefore, in Patent Document 1 and Patent Document 2, it is proposed to provide a skew correction unit that corrects the paper transport posture.

  On the other hand, in recent years, a paper folding function such as Z-folding has become an indispensable function as a new function, and a paper folding unit for that purpose can be installed as an external unit between the image forming apparatus and the paper processing apparatus. is there. Accordingly, the paper processing apparatus is required to improve the accuracy of skew correction for the folded paper, but the paper that has not been correctly folded (Z-folded) as shown in FIG. 2 has been conveyed. In such a case, it is difficult to perform skew correction with high accuracy by the methods according to Patent Document 1 and Patent Document 2.

  The present invention has been made in view of the above problems, and an object of the present invention is to provide a paper processing apparatus and an image forming system including the paper processing apparatus that can easily and accurately perform skew correction even on folded paper. And

Means for solving the problems / effects of the invention

In order to solve the above-described problems, a paper processing apparatus according to the present invention includes:
A paper processing apparatus that performs a predetermined process on a conveyed paper,
At least one set of first transport rollers for nipping and transporting the paper in the paper transport path;
At least one set of second transport rollers for nipping and transporting the paper downstream of the first transport rollers in the transport path;
Paper conveying means for rotating the first conveying roller and the second conveying roller to convey the paper in the conveying direction from the upstream side to the downstream side of the conveying path;
After the sheet has passed the first conveying roller, the rotation of the first conveying roller is stopped and the second conveying roller is reversed, the sheet is moved backward in the direction opposite to the conveying direction, and the trailing edge is stopped from rotating. A paper skew correction means for performing rear end alignment processing for correcting the skew with respect to the paper transport direction by pressing against the clamping position of the first transport roller;
It is characterized by providing.

  For example, in a sheet that is not correctly folded (Z-folded) as shown in FIG. 2, the folded portion where the deviation occurs is used as a reference according to the conventional method of performing skew correction on the front end side of the sheet. Since the skew of the paper cannot be corrected, subsequent processing such as punching is affected by the skew. Therefore, as in the above-described present invention, the second conveyance roller on the downstream side of the first conveyance roller can be reversed, the sheet is moved backward in the direction opposite to the conveyance direction, and the rotation of the rear end of the first conveyance roller is stopped. By performing skew correction (rear edge alignment processing) that presses against the roller clamping position, even if the paper being transported contains paper that has not been correctly folded as described above, the skew of the paper is corrected. It can be corrected with high accuracy.

  Next, the sheet processing apparatus of the present invention further includes a folded sheet detecting unit that detects that the folded sheet having the folded portion is conveyed on the front end side in the conveying direction, and the folded sheet detecting unit conveys the folded sheet. If detected, the paper skew correction means can be configured to perform rear edge alignment processing on the folded paper. As described above, since the skew correction by the rear edge alignment is particularly effective for the folded paper, the folded paper detection unit detects the conveyance of the folded paper and the skew correction by the rear edge alignment with respect to the folded paper. By performing the correction, the oblique direction of the folded sheet can be corrected accurately and efficiently.

  In addition, when the folded sheet detection unit does not detect the conveyance of the folded sheet, the sheet skew correction unit stops the rotation of the second conveyance roller and rotates the first conveyance roller to advance the sheet in the conveyance direction. Then, the front end is pressed against the nipping position of the second conveying roller whose rotation has stopped, so that the front end aligning process for correcting the oblique direction with respect to the sheet conveying direction can be performed. For the folded paper subjected to the folding process, the skew correction by the rear end alignment is performed, while for the paper not subjected to the folding process, the skew correction by the front edge alignment similar to the conventional one is performed. By doing so, paper other than folded paper is not retracted in the direction opposite to the transport direction, so that the processing efficiency can be improved.

  In addition, when the skew correction is performed by aligning the trailing edge of the folded sheet, the distance between the first conveying roller and the second conveying roller is equal to the conveying direction of the folded sheet by the trailing edge aligning process of the skew correcting unit. When correcting the inclination, the distance can be set such that the second conveying roller does not entrain the folded portion of the folded sheet. By setting such a distance, it is possible to prevent a problem that the folded sheet that has been retracted in the direction opposite to the conveyance direction is wound around the second conveyance roller and is bent or soiled.

  Next, in the sheet processing apparatus of the present invention, the sheet conveying unit and the skew correction unit have a driving device that rotates the second conveying roller independently of the first conveying roller, and the driving device The second transport roller is rotated in the first direction when moving forward in the transport direction, and the second transport roller is rotated in the second direction opposite to the first direction when retracting the paper in the direction opposite to the transport direction. It can be constituted as follows. Thereby, it is possible to satisfactorily realize the conveyance of the paper and the skew correction as described above.

  Alternatively, in the sheet processing apparatus of the present invention, the sheet conveying unit and the skew correction unit have a driving device that rotationally drives the first conveying roller and the second conveying roller, and the first conveying roller is unidirectional with respect to the driving device. Connected via a clutch, both the first transport roller and the second transport roller are rotated in the first direction when the paper is advanced in the transport direction, and the second is used when the paper is moved backward in the direction opposite to the transport direction. Only the transport roller can be configured to rotate in a second direction opposite to the first direction. According to this configuration, the driving sources of the first transport roller and the second transport roller can be combined into a simple configuration, and the skew correction by the rear end alignment can be satisfactorily realized.

  Next, in the paper processing apparatus of the present invention, the conveyance path between the first conveyance roller and the second conveyance roller is pressed against the nipping position of the first conveyance roller by the rear end aligning process of the skew correction unit. The paper sheet can be configured to have a gap that allows the paper sheet to bend. When the rear end of the sheet is pressed against the nipping position of the first conveying roller, the sheet can be bent in the gap, so that the skew correction can be performed satisfactorily.

  Next, the paper processing apparatus according to the present invention is based on the detection result of the orthogonal position detection unit and the orthogonal position detection unit that detects the position in the direction orthogonal to the conveyance direction of the sheet whose inclination is corrected by the inclination correction unit. And a drilling means for drilling at a predetermined position. Accordingly, the punching process can be performed on the sheet whose skew has been accurately corrected, so that it is possible to obtain a sheet with the punching positions aligned.

  Based on the above invention, an image forming system of the present invention forms an image on a sheet based on input image information, and performs a folding process on the sheet on which an image is formed by the image forming apparatus. And a sheet folding device that performs folding processing and performs the predetermined processing on the folded sheet. As a result, a series of processes from image formation through folding processing to predetermined processing such as perforation can be performed smoothly, and a paper on which predetermined processing such as perforation has been performed with high accuracy can be obtained. Obtainable.

Embodiments of the present invention will be described below with reference to the drawings.
FIG. 1 shows the overall configuration of a sheet processing apparatus 300 according to an embodiment of the present invention. In FIG. 1, a sheet processing apparatus 300 is installed on a side portion of an image forming apparatus 100 that is a digital copying machine, and a folding apparatus 200 is disposed therebetween. The sheet P on which an image is formed by the image forming apparatus 100 is conveyed by a pair of conveying rollers in the image forming apparatus 100 to reach the folding apparatus 200, where the sheet folding process is performed, and then the conveying rollers in the folding apparatus 200 are used. The sheet is conveyed and received by the pair of entrance rollers 1 as the first conveying roller of the present invention of the sheet processing apparatus 300.

  In front of the entrance roller pair 1, an entrance sensor S <b> 1 including a reflective sensor that detects the carry-in of the paper P is disposed. In the conveyance path from the entrance roller pair 1, the horizontal registration detection unit 10 as the orthogonal position detection unit according to the present invention that detects the deviation in the direction orthogonal to the conveyance direction of the paper, and the detection result of the horizontal registration detection unit 10 A punch unit 9 as a punching means of the present invention that can be driven in a direction perpendicular to the paper transport direction and punches a filing hole in the paper P, a punch scraper hopper 11 that accommodates punch scraps, and a paper P A shift switching claw A for switching to one of the transport paths I and II, and a staple switching claw B for switching to which of the transport paths II and III the paper P is transported A conveyance roller pair 2 is provided as a second conveyance roller of the present invention for guiding the paper P from the punch unit 9 to the shift switching claw A.

  By the switching, the shift switching claw A and the staple switching claw B are switched to a sheet P that goes in the direction of the upper tray T2 via the transport path I, and a paper P that goes in the direction of the tray T1 supported so as to be vertically movable via the transport path II. Then, the sheet P that is directed to the staple unit 20 via the transport path III is separated. A plurality of transport roller pairs for transporting the paper P from the staple switching claw B to the staple unit 20 are arranged on the transport path III toward the staple unit 20, and the paper P is aligned through the transport path IV. The paper is conveyed in the direction of the jogger fence 3 and the rear end fence 4 to be stacked, and after being stacked in a predetermined number, is stapled by the stapler 5 and discharged to the tray T1 through the discharge belt and the discharge claw 6 through the discharge roller pair 7. .

  The lateral registration detection unit 10 has a lateral registration sensor moving motor that moves in a direction orthogonal to the transport direction of the paper P, and the punch unit 9 transports the punch unit 9 based on the detection result of the lateral registration detection unit 10. A punch moving motor that moves in a direction perpendicular to the direction and a punch drive motor that punches the paper P, so that the punching position with respect to the end of the paper P can be aligned. ing. These can be configured as well-known drilling means as disclosed in, for example, “Japanese Patent Laid-Open No. 2003-128337”.

  FIG. 11 is a block diagram showing details of the electrical configuration of the sheet processing apparatus 300 according to the first embodiment of the present invention. In the figure, the configuration of the part particularly related to the processing of the present invention is shown on the left side of the CPU 33. The sheet processing apparatus 300 is configured with a central processing unit (CPU) 33 as a center, has a RAM serving as a work area for the CPU 33 and a ROM storing various controls and data, and drives various motors arranged in the apparatus. Drivers, various sensors, etc. Specifically, the CPU 33 outputs a control signal to a motor driver via an I / O interface (not shown), and an inlet conveyance motor 31 that drives the inlet roller pair 1 and a shift conveyance that drives the conveyance roller pair 2. Motor 32, transport motor for driving transport rollers provided in transport paths I to III, paper discharge motor for driving paper discharge rollers, staple moving motor for moving the stapling device, jogger motor for moving the jogger fence Control of motors constituted by stepping motors such as a punch movement motor for moving the punch unit 9 and a horizontal registration sensor movement motor for moving the lateral registration detection unit 10 is performed. Similarly, other than stepping motors such as a shift tray up / down motor, a shift motor, a staple motor for driving a stapling device, a discharge motor for driving a discharge belt, and a punch drive motor for driving a punch unit 9 for punching paper. The motor is also controlled. Similarly, a switching solenoid for driving the switching claws A and B for switching the transport paths I to III through which the sheet is transported is controlled.

  The image forming apparatus 100, the folding apparatus 200, and the sheet processing apparatus 300 are connected to each other via a serial interface, and exchange necessary control data by serial communication. When receiving a signal indicating that the “Z-folding processing mode” has been selected by the user from the image forming apparatus 100, the folding apparatus 200 performs a paper folding process on the paper P conveyed from the image forming apparatus 100, and FIG. A Z-folded sheet with the front end side in the transport direction Z-folded is formed, and then transported to the sheet processing apparatus 300. Further, the sheet processing apparatus 300 receives the signal indicating that the “Z-folding processing mode” is selected, detects that the Z-folded sheet is conveyed, and performs the process described later.

  As described above, the electrical configuration centered on the CPU 33 of the sheet processing apparatus 300 functions as the sheet conveying unit, the sheet skew correcting unit, and the folded sheet detecting unit of the present invention. Hereinafter, the sheet skew (skew) correction processing performed by these means will be described. 4 to 10 are diagrams showing a process of skew correction of the Z-folded paper, and FIG. 12 is a flowchart showing a series of operations. FIG. 3 shows a top view and a side view of the sheet receiving unit of the sheet processing apparatus 300 according to the first embodiment in which such processing is performed. The entrance roller pair 1 is driven by an entrance transport motor 31, and the transport roller pair 2 is driven by a shift transport motor 32. In the transport path between the entrance roller pair 1 and the transport roller pair 2, as will be described later, a gap portion 30 is provided to allow bending that occurs when a sheet is pressed against the entrance roller pair 1. .

  First, in the first step shown in FIG. 4, when the CPU 33 receives an activation signal from the image forming apparatus 100, the CPU 33 drives the entrance conveyance motor 31 and the shift conveyance motor 32. Next, the paper P is transported into the paper processing apparatus 300 by the transport rollers in the folding apparatus 200. When the paper P is transported, the entrance sensor S1 is turned on, and subsequently transported to the entrance roller pair 1, and reaches the transport roller pair 2 through the punch unit 9 and the lateral registration detector 10. Thereafter, when the sheet P passes through the entrance roller pair 1, the transport by the entrance roller pair 1 and the transport roller pair 2 is stopped. At this time, the timing of stopping the conveyance is determined by whether or not a predetermined time has elapsed since the entrance sensor S1 was turned off by the timer of the CPU 33.

  Next, in the second step shown in FIG. 5, when the transport of the paper P is stopped, the CPU 33 reverses only the shift transport motor 32 and moves the paper P backward in the direction opposite to the transport direction. As a result, the paper P is fed toward the entrance roller pair 1 in the drive stopped state, and the paper P is prevented from being conveyed with its rear end pressed against the clamping position of the entrance roller pair 1. . However, since the conveyance roller pair 2 continues to reverse so as to retract the paper P, the paper P has its rear end and the entrance centered on the position where it contacts the entrance roller pair 1 as shown in the third step shown in FIG. Rotate in-plane so that the nipping position of the roller pair 1 is parallel (rear end alignment process). In this way, the skew of the paper P is corrected. The shift conveyance motor 32 stops its driving when a predetermined time has elapsed since the start of reversal.

  Here, when the rear end of the sheet is pressed against the nipping position of the entrance conveyance roller pair 1 whose rotation has stopped, the sheet P is stagnate, but the sheet is bent near the entrance roller pair 1. Therefore, the paper P can smoothly form stagnation due to this gap. Further, the distance between the entrance roller pair 1 and the transport roller pair 2 is determined such that the transport roller pair 2 does not entrain the folded portion of the Z-folded paper when the paper P is pressed against the entrance roller pair 1. Therefore, the folded portion is not caught by the conveying roller pair 2 and is not folded or wrinkled.

  Next, in the fourth step shown in FIG. 7, the lateral registration detection sensor (not shown) of the lateral registration detection unit 10 corrects the lateral registration of the paper, and then the CPU 33 moves the lateral registration detection sensor after the paper P. It is determined whether or not a predetermined time has passed since the end was detected (whether or not the sheet has reached the punching position), and the conveying roller pair 2 is stopped again. Then, in the fifth step shown in FIG. 8, the punch unit 9 is moved in the direction orthogonal to the transport direction based on the detection result of the lateral registration detection unit 10, and the punching process is performed in the sixth step shown in FIG. Thereafter, in the seventh step shown in FIG. 10, the shift conveyance motor 2 is rotated forward so that the paper P is conveyed in the conveyance direction and discharged through one of the conveyance paths I to III. Thus, a series of processes including the skew correction process is completed.

  The conventional skew correction method using the leading edge of the paper as a reference has a problem that if the folded side of the Z-folded paper is conveyed as the leading edge, the punching process cannot be performed accurately if folding is not performed correctly. . Therefore, as described above, the Z-folded paper is once retracted and the skew correction is performed at the trailing edge of the paper, so that the skew correction is correctly performed regardless of the Z-fold state, and as a result, the punch processing is performed with high accuracy. It is possible to do well.

  Since a sheet that has not been folded can be skew-corrected at the front end of the sheet as in the conventional case, when such a sheet is conveyed, a modified example of the above-described process is shown in the flowchart of FIG. It can be processed. In other words, the skew correction (rear edge alignment process) described above is performed only when the CPU 33 receives a “Z-folding processing mode” selection signal from the image forming apparatus 100 (function as the folded sheet detecting means of the present invention). On the other hand, when such a signal is not received, the same skew correction (front end alignment processing) as in the conventional case is performed. Specifically, as shown in the right part of the flowchart of FIG. 13, the front end aligning process rotates the entrance roller pair 1 to advance the paper P in the transport direction, and the transport roller pair 2 whose front end has stopped rotating. The skew of the paper is corrected by pressing it against the nipping position. Such a front end alignment process is similar to a known process as disclosed in, for example, “JP 2002-160848 A”. In addition, the detection of the folded paper is performed by, for example, a reflection type sensor or the like provided on the upstream side of the entrance roller pair 1 (not only in the paper processing apparatus 300 but also in the folding processing apparatus 200). This can also be realized by measuring the length of the sheet in the conveyance direction.

  Hereinafter, a sheet processing apparatus 300 according to a second embodiment of the present invention will be described. In addition, about the part which concerns on the structure similar to said embodiment, the same number is attached | subjected and description is abbreviate | omitted. FIGS. 14 to 16 relate to a sheet processing apparatus 300 according to the second embodiment. FIG. 14 is a top view and a side view of a sheet receiving unit, FIG. 15 is a flowchart, and FIG. is there. According to FIG. 14, the entrance roller pair 1 and the transport roller pair 2 use a motor 34 as a common drive source, and the entrance roller pair 1 is connected to the motor 34 via a one-way clutch 35. As a result, the inlet roller pair 1 rotates only in the paper transport direction. That is, when the motor 34 rotates in the forward direction, both the inlet roller pair 1 and the conveying roller pair 2 rotate in the direction in which the sheet is conveyed, and when the motor 34 is reversed, only the conveying roller pair 2 rotates in the direction in which the sheet moves backward. With such a configuration, as shown in FIGS. 15 and 16, skew correction processing (rear end alignment processing) similar to that in the first embodiment can be performed only by controlling one motor 34.

  As mentioned above, although embodiment of this invention was described, this invention is not limited to these, In the range which does not deviate from the summary, it can change suitably and can implement.

The figure which represents roughly the internal structure of the paper processing apparatus of this invention The figure showing the Z-fold paper by which the front end side of the conveyance direction was Z-folded The top view and side view of the paper receiving part of the paper processing apparatus which concern on 1st Embodiment The figure showing the 1st step of the skew correction process in the paper receiving part of FIG. Next, a diagram representing the second step Next, a diagram representing the third step Next, a diagram representing the fourth step Next, a diagram representing the fifth step Next, a diagram representing the sixth step Next, a diagram representing the seventh step 1 is a block diagram illustrating an electrical configuration of a sheet processing apparatus according to a first embodiment. Flowchart showing the skew correction processing shown in FIGS. The flowchart showing the modification of the skew correction process shown in FIG. The top view and side view of the paper receiving part of the paper processing apparatus which concern on 2nd Embodiment Flowchart illustrating skew correction processing of the sheet processing apparatus according to the second embodiment. FIG. 3 is a block diagram illustrating an electrical configuration of a sheet processing apparatus according to a second embodiment.

Explanation of symbols

1 Inlet roller pair (first transport roller)
2 Transport roller pair (second transport roller)
9 Punch unit (drilling means)
10 Horizontal registration detection unit (orthogonal position detection means)
100 Image forming device (digital copier)
200 Paper folding device 300 Paper processing device

Claims (9)

A paper processing apparatus that performs a predetermined process on a conveyed paper,
At least one set of first transport rollers for nipping and transporting the paper in the paper transport path;
At least one set of second conveying rollers for nipping and conveying the sheet downstream of the first conveying roller in the conveying path;
Paper conveying means for conveying the paper in the conveying direction from the upstream side to the downstream side of the conveying path by rotating the first conveying roller and the second conveying roller;
After the sheet passes through the first conveying roller, the rotation of the first conveying roller is stopped and the second conveying roller is reversed, the sheet is moved backward in the direction opposite to the conveying direction, and the trailing end is rotated. A paper skew correction unit that performs rear edge alignment processing for correcting the skew of the paper with respect to the transport direction by pressing against the nipping position of the first transport roller that has stopped.
A sheet processing apparatus comprising:   Folding paper detection means for detecting that folded paper having a folding portion on the front end side in the transport direction is further provided, and when the folded paper detection means detects transport of the folded paper, the paper is inclined. The sheet processing apparatus according to claim 1, wherein the correction unit performs the trailing edge alignment process on the folded sheet.   When the folded sheet detecting means does not detect the conveyance of the folded sheet, the sheet oblique direction correcting means stops the rotation of the second conveyance roller and rotates the first conveyance roller in the conveyance direction. The sheet processing apparatus according to claim 2, wherein a front end alignment process is performed to correct the skew of the sheet with respect to the conveyance direction by advancing the sheet and pressing the front end against a holding position of the second conveyance roller whose rotation has stopped. .   The distance between the first transport roller and the second transport roller is the second transport when correcting the skew of the folded sheet with respect to the transport direction by the trailing edge aligning process of the skew correction unit. The paper processing apparatus according to claim 2 or 3, wherein the roller is set to a distance at which the folded portion of the folded paper is not caught.   The paper transport unit and the skew correction unit have a drive device that rotates the second transport roller independently of the first transport roller, and the drive device moves the paper forward in the transport direction. The second transport roller is rotated in a first direction, and the second transport roller is rotated in a second direction opposite to the first direction when the sheet is retracted in a direction opposite to the transport direction. The sheet processing apparatus according to any one of 1 to 4.   The paper transport unit and the skew correction unit have a drive device that rotationally drives the first transport roller and the second transport roller, and the first transport roller is connected to the drive device via a one-way clutch. When the paper is advanced in the transport direction, both the first transport roller and the second transport roller are rotated in the first direction, and when the paper is moved backward in the direction opposite to the transport direction, the second transport roller is rotated. 5. The sheet processing apparatus according to claim 1, wherein only the conveying roller is rotated in a second direction opposite to the first direction. 6.   The conveyance path between the first conveyance roller and the second conveyance roller is such that the sheet pressed against the nipping position of the first conveyance roller is bent by the rear end alignment process of the oblique direction correction unit. The sheet processing apparatus according to claim 1, wherein the sheet processing apparatus has an allowable gap.   Perforation is performed at a predetermined position on the sheet based on the detection result of the orthogonal position detection means for detecting the position of the sheet whose skew has been corrected by the skew correction means in the direction orthogonal to the transport direction. The sheet processing apparatus according to claim 1, further comprising a punching unit. An image forming apparatus that forms an image on a sheet based on input image information, a sheet folding apparatus that performs folding processing on the sheet on which an image is formed by the image forming apparatus to form a folded sheet, and the folded sheet An image forming system comprising: the sheet processing apparatus according to claim 1 that performs predetermined processing on the image forming apparatus.

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