JP2013116789A - Device and method for folding sheet - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a sheet folding device that, when a sheet bundle is folded in three, prevents bundled sheets folded in three from being irregularly aligned in a width direction thereof depending on the number of sheets.SOLUTION: The sheet folding device is configured to fold a sheet bundle Sb at a position α thereof by pushing the bundled sheet Sb into a nip 2 of folding rollers 1A, 1B with a pushing plate 102 (a to c), push the bundled sheet Sb that has been folded at the position α into a nip 3 of folding rollers 1B, 1C with a pushing plate 103 (d to e) to fold the bundled sheet Sb at a position β thereof. The sheet folding device starts the pushing operation by the pushing plate 103 in earlier timing as the number of sheets constituting the bundled sheet Sb increases.

Description

  The present invention relates to a sheet folding apparatus and a sheet folding method for folding a sheet bundle composed of a plurality of sheets output from an image forming apparatus or the like.

2. Description of the Related Art A sheet post-processing apparatus having a sheet folding apparatus that folds a printed sheet output from an image forming apparatus by a job executed by an image forming apparatus such as a printer in three has been developed. Tri-folding of a sheet is used, for example, when a document (sheet) larger than an envelope is folded and placed in an envelope and mailed.
As such a sheet folding apparatus, in Patent Document 1, as shown in FIG. 10A, a sheet S folded at a first position S1 is conveyed to the top and folded across a conveyance path. A knife-like folding plate member 902 arranged to face the roller pair 901 is moved toward the sheet S and brought into contact with the sheet surface, so that the sheet S is folded into a pair of folding rollers as shown in FIG. The structure which folds in 2nd position S2 by pushing into nip 903 of 901 is disclosed.

  The operation of folding the sheet S at the second position by moving the folding plate member 902 (second folding operation) is that the front end of the sheet S conveyed to the top after the fold is folded at the first position S1. The process is started after a predetermined time has elapsed since the detection by the detection means.

JP 2005-41658 A

The technique of the above-mentioned Patent Document 1 is a technique for folding a single sheet into three, but if this is applied to a sheet bundle composed of a plurality of sheets, the sheet is folded in three according to the number of sheets in the sheet bundle. There is a problem that the width of the sheet bundle becomes uneven depending on the number of sheets.
That is, if there is only one sheet, the width of the sheet S after being folded in three as shown in FIG. 10C is the interval L from the first position S1 to the second position S1.

On the other hand, when the sheet bundle Sb is folded in the same manner as one sheet S, as shown in FIG. 10D, the second folding is performed after a predetermined time elapses from the detection of the leading end Sc of the sheet bundle Sb. When the operation is performed, as shown in FIG. 10E, the width of the sheet bundle Sb after being folded in three is set to the width L when the sheet S is folded in three, as much as the number of sheets at the second position S2. Only the thickness D increases.
The thickness of one sheet is about 0.1 to 0.2 [mm] if the sheet is generally used, and if the number of sheets is 20, the thickness D is about 2 to 4 [mm]. As the number of sheets increases, the width of the sheet bundle Sb after being folded in three becomes wider.

If the width of the sheet bundle Sb after being folded in three is not uniform depending on the number of sheets, the appearance of the sheet bundle after being folded in three is deteriorated. In addition, if the width of the sheet bundle after being folded in three is too wide, when the sheet bundle is put into an envelope of a prescribed size, if one sheet is included in the envelope, it is included in a plurality of sheets. There is also a possibility that inconvenience such as disappearance may occur.
Such a problem is not limited to folding the paper output from the image forming apparatus, and may generally occur in a sheet folding apparatus that folds a sheet bundle made up of a plurality of sheets such as paper.

  The present invention has been made in view of the above-described problems, and when the sheet bundle is folded in three, the width of the sheet bundle after being folded in three depending on the thickness of the sheet bundle is suppressed. An object of the present invention is to provide a sheet folding apparatus and a sheet folding method.

  In order to achieve the above object, a sheet folding apparatus according to the present invention folds a sheet bundle composed of a plurality of sheets by a first folding operation, and then folding the sheet bundle by a second folding operation. The apparatus is configured to convey the sheet bundle after being folded by the first folding operation in the first direction with the fold as the head, or in the second direction opposite to the first direction with the fold as the rear end side. For the second folding with the conveying means for conveying the sheet and the pair of rotating bodies arranged in the direction in which the central axis of rotation intersects the conveying direction along the conveying path of the sheet bundle conveyed by the conveying means Then, the pressing member disposed opposite to the pair of rotating bodies with the conveying path interposed therebetween is moved toward the sheet bundle being conveyed, and is brought into contact with the sheet surface of the sheet bundle, so that the sheet bundle is Pushing into the nip of the rotating body pair The acquisition means for acquiring information indicating the thickness of the sheet bundle, and the start timing of the pushing operation by the pushing member with respect to the sheet bundle as the thickness of the acquired sheet bundle increases. Control means for controlling the pushing means so as to be faster when the sheet is conveyed in the first direction, or slower when the sheet bundle is conveyed in the second direction. To do.

  Further, the control means starts the pushing operation at a first time when the thickness of the sheet bundle is the first thickness, and when the thickness of the sheet bundle is the second thickness larger than the first thickness, When the sheet is conveyed in the first direction, it starts at a second time point earlier than the first time point by a predetermined time according to the difference between the first and second thicknesses, or the sheet bundle is moved in the second direction. May be started at a second time point later than the first time point by the predetermined time.

  Here, the information indicating the thickness of the sheet bundle is information indicating the number of sheets, and the control unit performs the push-in operation, and the acquired number of sheets is a first number corresponding to the first thickness. In the case of the first time point, and in the case of the second number corresponding to the second thickness, it starts at the second time point, and the predetermined time is the first and second number of sheets. The time may be determined according to the difference.

  Here, the acquisition unit further acquires information indicating the sheet type or basis weight, and the first number corresponds to the sheet type or basis weight for each different sheet type or basis weight. , Different values are determined, and the second number is determined for each different sheet type or basis weight, and different values corresponding to the sheet type or basis weight are determined. Each of the first and second numbers may be a value corresponding to the acquired sheet type or basis weight.

  The first time point is when a first predetermined time has elapsed from the execution of the first folding operation, and the second time point is when the sheet bundle is conveyed in the first direction. When a time obtained by subtracting the predetermined time from a predetermined time is defined as a second predetermined time, the second predetermined time has elapsed since the execution of the first folding operation, or the sheet bundle is When transported in two directions, the second predetermined time from the execution of the first folding operation is defined as a second predetermined time obtained by adding the predetermined time from the first predetermined time. It may be when it has passed.

  Here, in order to perform the first folding with the rotating body pair different from the rotating body pair, the pressing member different from the pressing member is moved toward the sheet bundle before being folded, A pressing means different from the pushing means for bringing the sheet bundle into contact with the sheet surface of the sheet bundle and pushing the sheet bundle into the nip of the other pair of rotating bodies, and the first time point is the other pushing The first predetermined time may have elapsed since the start of the pushing operation by the member.

  Further, the acquisition means further acquires information indicating the thickness of one sheet, and the control means has a thickness of the first sheet bundle and a thickness that is greater than that of the sheets constituting the first sheet bundle. When the thickness of the second sheet bundle made of thick sheets is the same, the start timing of the pushing operation by the pushing member with respect to the second sheet bundle is set higher than the start timing of the pushing action by the pushing member with respect to the first sheet bundle. The sheet bundle may be advanced when it is conveyed in the first direction, or may be delayed when it is conveyed in the second direction.

  The present invention relates to a sheet folding method in a sheet folding apparatus that folds a sheet bundle composed of a plurality of sheets by a first folding operation and then folds the sheet bundle by a second folding operation. A conveying step of conveying the sheet bundle after being folded by the folding operation in the first direction with the fold at the top, or conveying the fold in the second direction opposite to the first direction on the rear end side; An acquisition step for acquiring information indicating the thickness of the sheet bundle, and a pressing member disposed opposite to the pair of rotating bodies with the conveyance path of the sheet bundle conveyed in order to perform the second folding, the sheet And a control step for controlling a pushing means for moving the bundle toward the sheet, abutting against the sheet surface of the sheet bundle, and pushing the sheet bundle toward the nip of the pair of rotating bodies. And In the recording control step, as the thickness of the acquired sheet bundle increases, the start timing of the pushing operation by the pushing member with respect to the sheet bundle becomes earlier when the sheet bundle is conveyed in the first direction, Alternatively, when the sheet bundle is conveyed in the second direction, control is performed so as to be delayed.

For example, when the sheet bundle is conveyed in the first direction as described above, the start timing of the pushing member is pushed earlier as the thickness of the sheet bundle increases. Rather than having a constant configuration regardless of the number of sheets, it is possible to suppress unevenness of the width of the sheet bundle after being folded in three.
That is, in the configuration in which the start timing of the pushing operation of the pushing member is constant regardless of the thickness of the sheet bundle, the thickness of the fold increases as the thickness of the sheet bundle increases due to an increase in the number of sheets. The width of the sheet bundle after being folded in three is widened.

On the other hand, if the configuration of the present invention is adopted, the start timing of the pushing operation of the pushing member can be advanced by the extent of the width, so for example, the width of the thick sheet bundle after being folded in three is smaller than this. It is possible to approach the width of the thin sheet bundle after being folded in three, and it is possible to suppress the unevenness of the width of the sheet bundle after being folded in three depending on the thickness of the sheet bundle.
Instead of the above, when the sheet bundle is conveyed in the second direction, the same as described above also applies when the start timing of the pushing operation of the pushing member is delayed as the thickness of the sheet bundle increases. The effect of can be obtained.

It is a figure which shows the whole structure of a sheet | seat post-processing apparatus. It is a figure which shows typically a mode before and after a paper is folded by a paper folding function. FIG. 5 is a schematic enlarged view showing a configuration of a sheet folding unit. It is a block diagram which shows the structure of a control part. FIG. 10 is a schematic diagram for explaining an operation when a sheet bundle is folded in three. FIG. 10 is a schematic diagram for explaining the reason why the widths of the sheet bundle Sb after being folded in three are uneven. FIG. 6 is a schematic diagram illustrating a state at the start of a second folding operation and a width of a sheet bundle Sb after being folded in three in the present embodiment. It is a figure for demonstrating the example of the content of the timing information stored in the timing table. It is a flowchart which shows the processing content of the trifold control performed by a control part. It is a schematic diagram for demonstrating the conventional trifold operation | movement.

Hereinafter, an example in which the sheet folding apparatus and the sheet folding method according to the present invention are applied to a sheet post-processing apparatus having a function of folding a sheet output from an image forming apparatus will be described.
(1) Overall Configuration FIG. 1 is a diagram illustrating an overall configuration of a sheet post-processing apparatus 1.
As shown in the figure, the sheet post-processing apparatus 1 includes a paper carry-in unit 11, conveyance path switching units 12 and 13, a paper discharge unit 14, a discharge tray 15, a binding processing unit 16, and a stacking tray unit 17. A paper folding unit 18, a post-processing tray 19, a control unit 20, a conveyance motor 21, and the like, and a staple binding function for stapling the paper output by the discharge roller pair 9 of the image forming apparatus 8. And a function of performing post-processing including a sheet folding function for folding in half or in three.

2A and 2B are diagrams schematically illustrating a state before and after the sheet is folded by the sheet folding function. FIG. 2A illustrates an example of folding in two, and FIG. 2B illustrates an example of folding in three. .
As shown in FIG. 2A, the half-folding is a half-folding with the position where the paper S is divided into two equal parts along the paper transport direction as a target folding position α. As shown in FIG. 4, the three-fold is first made so that the folded SA is folded between the folded SB and SC, with the two positions spaced apart in the paper transport direction as the target folding positions α and β. After folding at the position α (first time), the paper S is folded once again at the position β (second time) and folded in three, which is called a so-called three-fold winding. Tri-folding is not limited to one sheet, and can be performed on a sheet bundle composed of a plurality of sheets S. The operation of folding the sheet bundle in three will be described later.

Returning to FIG. 1, the paper carry-in unit 11 receives the paper output from the image forming apparatus 8 and conveys it in the direction indicated by the arrow a.
The conveyance path switching unit 12 switches the conveyance destination of the paper from the paper carry-in unit 11 to one of the conveyance paths 27 and 28 according to an instruction from the control unit 20. When the post-processing is not performed on the sheet or when the staple binding function is performed, the sheet is switched to the conveyance path 27, and when the sheet folding function is performed, the sheet is switched to the conveyance path 28.

The conveyance path switching unit 13 sends the sheet conveyed through the conveyance path 27 according to an instruction from the control unit 20 to the sheet discharge unit 14 when the post-processing is not performed, and the branch path 29 when performing the stapling function. Lead to. The sheet guided to the branch path 29 is conveyed to the binding processing unit 16.
The paper discharge unit 14 discharges the paper transported through the transport path 27 out of the apparatus and stores it in the discharge tray 15.

The binding processing unit 16 receives the sheets from the branch path 29 one by one and stores them on the binding tray, and when the number of sheets to be stapled is stacked on the binding tray, Then, stapling is performed, and the bundle of sheets after stapling is sent to the stacking tray unit 17.
The stacking tray unit 17 stores the staple-bound paper bundle. Here, as the amount of sheet bundles to be accommodated increases, the stacking tray unit 17 is lowered to accommodate large-capacity sheet bundles.

The sheet folding unit 18 folds the sheet transported through the transport path 28 in the case of performing the sheet folding function, and then stores the sheet in the post-processing tray 19.
The conveyance motor 21 rotationally drives each pair of conveyance rollers arranged in the conveyance paths 27 and 28 in the sheet post-processing apparatus 1.
The control unit 20 controls each unit such as the paper carry-in unit 11 to the transport motor 21 so as to smoothly execute the transport and post-processing of the paper.

(2) Configuration of Paper Folding Unit 18 FIG. 3 is a schematic enlarged view showing the configuration of the paper folding unit 18.
As shown in the figure, the paper folding unit 18 includes a folding roller group 101, pushing plates 102 and 103, a conveyance path switching claw 104, a stacker 105, a paper leading edge detection sensor 106, a pushing plate drive motor 107, 108, a stacker motor 109, a switching claw drive actuator 110, and the like.

The folding roller group 101 includes three folding rollers 1A, 1B, and 1C.
The folding rollers 1A and 1B are in contact with each other, and a nip 2 is formed at the contact portion, and is a pair of rollers used to fold the paper in two and three, and along the conveyance path Pa, the center of rotation The shaft is arranged in a direction crossing the transport direction.
The folding roller 1B rotates in the direction indicated by the arrow B while the folding roller 1A rotates in the direction indicated by the arrow A. This rotation is performed by the driving force of the transport motor 21, but may be driven by another motor (not shown).

The folding roller 1C is a roller that is used as a pair with the folding roller 1B only when it is folded in three. The folding roller 1C is in contact with the folding roller 1B, and a nip 3 is formed at the contacted portion, in the direction indicated by the arrow C. Rotate.
Each of the folding rollers 1 </ b> A to 1 </ b> C has an elastic layer such as rubber, and is pressed against adjacent rollers with a pressure necessary to fold the paper. Each of the folding rollers 1A to 1C has substantially the same axial length. Hereinafter, the folding rollers 1A and 1B may be referred to as a folding roller pair 121, and the folding rollers 1B and 1C may be referred to as a folding roller pair 122.

  The stacker 105 hits the lower end (the front end of the sheet) of the sheet conveyed in the conveyance path Pa (the path on the lower end side of the conveyance path 28) in the direction indicated by the arrow D (downward), and stops the sheet. It is something to support. When a plurality of sheets are continuously conveyed when the sheet bundle is folded in three, the sheet bundle is obtained by stacking the plurality of sheets on the stacker 105.

  The stacker 105 is inclined and the next (n + 1) -th sheet is stacked on the folding roller pair 121 side of the n-th sheet with respect to the n-th sheet continuously conveyed. That is, the stacker 105 is inclined so that the sheet conveyed next to the previously conveyed sheet is stacked away from the pushing plate 102, and the first sheet hits the pushing plate 102.

The bottom 1051 of the stacker 22 is supported so as to be movable along the transport path Pa in the direction indicated by the arrow E. By moving the bottom portion 1051, the position of the sheet on the transport path Pa so that the target folding position α is located at the position J facing the front end of the pushing plate 102, regardless of the size of the sheet. Can be adjusted.
The bottom 1051 of the stacker 22 is moved by the driving force of the stacker motor 109. The stacker motor 109 is driven and controlled by the control unit 20, and the control unit 20 preliminarily changes the sheet size according to the size. The bottom part 1051 of the stacker 22 is moved to the determined stop position, and is stopped at the stop position.

The pushing plate 102 moves toward the nip 2 of the pair of folding rollers 121 via the paper that is stopped and supported by the stacker 105 on the conveyance path Pa, and the leading end abuts against the surface of the paper. This is for performing a pushing operation of pushing the portion of the target folding position α into the nip 2 of the folding roller pair 121.
The pushing plate 102 is disposed at a position facing the folding roller pair 121 across the conveyance path Pa, and the length along the axial direction of the folding roller 1A is substantially the same as that of the folding roller 1A. It is supported by an apparatus housing (not shown) so as to be movable along a direction intersecting Pa, here, a direction indicated by an arrow F that forms a right angle.

The pushing plate 102 has a leading end that passes through the conveyance path Pa from a standby position (a position indicated by a solid line) separated from the conveyance path Pa by the driving force of the pushing plate drive motor 107. After moving to the position of the nip 2 (position indicated by a broken line), an operation of returning to the standby position is performed.
The paper whose portion at the target folding position α is pushed into the nip 2 of the folding roller pair 121 by the pushing operation of the pushing plate 102 is drawn into the nip 2 with the portion at the target folding position α at the head. When the paper passes through the nip 2, the paper is folded by the pressure of the folding roller pair 121, and the paper is creased. In the above description, the operation of folding a single sheet has been described. However, the same operation is performed for a sheet bundle.

Hereinafter, the folding operation for one sheet will be described with reference to FIG. 3, and the details of the folding operation for the sheet bundle will be described with reference to FIG.
The paper folded by the pair of folding rollers 121 is transported along the transport path Pb at the transport speed V by the pair of folding rollers 121 and reaches the transport path switching claw 104.
The conveyance path switching claw 104 switches the conveyance path of the sheet after being folded by the folding roller pair 121 between the case of folding in two and the case of folding in three according to an instruction from the control unit 20. Specifically, when the paper is folded in half, the paper is transported along the transport path Pb in the posture shown by a solid line, and when the paper is folded in three, the posture is shown by a broken line and sent to the transport path Pd. The posture of the conveyance path switching claw 104 is changed by the driving force of the switching claw driving actuator 110. The switching claw drive actuator 110 is composed of, for example, a solenoid.

In the case of folding in half, the sheet conveyed through the conveyance path Pb is discharged to the post-processing tray 19 (FIG. 1).
When the folding plate 103 is folded in three, the sheet after being folded by the pair of folding rollers 121 moves toward the nip 3 of the pair of folding rollers 122 while the sheet is being conveyed on the conveyance path Pd, and the leading end is the sheet. 2 and a target folding position (β: FIG. 2) of the sheet is pushed into the nip 3 of the pair of folding rollers 122 to perform a pushing operation.

In the case of three folds, the folding roller pair 121 has a function of a rotating body pair for transporting the sheet after being folded in the first folding operation to the head of the fold, and the folding roller pair 122 is the second time It has the function of a rotating body pair for performing the folding operation.
The pushing plate 103 is disposed at a position facing the folding roller pair 122 across the conveyance path Pb, and the length along the axial direction of the folding roller 1C is substantially the same as that of the folding roller 1C. It is movably supported by the apparatus casing along a direction intersecting Pb, here, a direction indicated by a right-angled arrow G.

The pushing plate 103 is driven by the driving force of the pushing plate drive motor 108 from a standby position (a position indicated by a solid line) that is separated from the conveyance path Pb, and a leading end portion of the pushing plate 103 passes through the conveyance path Pb. After moving to the position of the nip 3 (position indicated by a broken line), an operation of returning to the standby position is performed.
The sheet in which the target folding position β is pushed into the nip 3 of the pair of folding rollers 122 by the pushing operation of the pushing plate 103 is drawn into the nip 3 with the target folding position β at the head, and the nip 3 Is passed through the transport path Pc by the pressure of the pair of folding rollers 122 and is discharged to the post-processing tray 19.

  The pushing operation by the pushing plate 103 is executed in a state where the fold (the leading end side in the carrying direction) of the sheet after being folded by the first folding operation is carried to the carrying path Pd. The path portion in which the movement trajectory of 103 is on the downstream side in the transport direction from the position U where the transport path Pb intersects and moves away in the direction opposite to the movement direction G during the pushing operation of the push plate 103 toward the downstream in the transport direction. That is, it includes a path portion that is inclined to the upper left in the figure.

By providing such a path portion that is inclined to the upper left, when the paper is pushed into the nip 3 of the folding roller pair 122 and folded, the posture of the paper starts with the front end of the push plate 103 as the head. When the sheet is V-shaped, the leading end side (folded SA and SB side) of the sheet also takes a posture along the posture on the conveyance path Pd.
Therefore, when such an inclination is not provided (when the conveyance path Pb is conveyed), the front end side in the sheet conveyance direction jumps from the position of the conveyance path Pb to the attitude of the conveyance path Pd during the folding operation. Occasionally, the shake of the paper that occurs is suppressed, and the second folding operation on the paper after being folded by the first folding operation can be performed more smoothly.

The paper leading edge detection sensor 106 is arranged upstream of the pushing position J by the pushing plate 102 in the conveying direction Pa in the conveying path Pa, detects the leading edge of each sheet conveyed in the conveying path Pa, and detects the detection signal. Is sent to the control unit 20.
When the sheet bundle is folded in three based on the detection signal of the sheet leading edge detection sensor 106, the control unit 20 can know that all the sheets of the sheet bundle to be folded are accommodated in the stacker 105. When the paper is stored in the stacker 105, the folding operation is started.

The paper leading edge detection sensor 106 is, for example, a reflective optical sensor, but is not limited to an optical sensor as long as it can detect the leading edge of the paper being conveyed, and other types of sensors, etc. May be used.
(3) Configuration of Control Unit 20 FIG. 4 is a block diagram showing the configuration of the control unit 20.

As shown in the figure, the control unit 20 includes a CPU 51, a ROM 52, a RAM 53, a stacker position control unit 54, a pushing plate drive control unit 55, a timing table 56, and a timer 57 as main components. Each part can communicate with each other.
When the CPU 51 receives from the image forming apparatus 8 an execution instruction for post-processing such as a staple binding function and a paper folding function, and paper information including the size and number of sheets to be subjected to post-processing, and the paper type, the received paper information Then, the paper carry-in unit 11 to the carry motor 21 are controlled to smoothly execute the post-processing instructed from the image forming apparatus 8.

The ROM 52 stores programs relating to paper conveyance and post-processing, and the RAM 53 serves as a work area for the CPU 51.
The stacker position control unit 54 controls the stacker motor 109 when executing the sheet folding function, and moves the position of the bottom portion 1051 of the stacker 105 to a position corresponding to the sheet size. The paper size is acquired from the above paper information.

The pushing plate drive control unit 55 controls the pushing plate drive motors 107 and 108 to execute the pushing operation by the pushing plates 102 and 103, and executes the two-fold or three-fold function.
In the timing table 56, timing information (described later) used when the trifold function is executed is written.
(4) Description of Operation when Folding a Sheet Bundle in Three FIG. 5 is a schematic diagram for explaining an operation when folding a sheet bundle in three. Note that the same method is used for folding a single sheet in three.

FIG. 5A shows a state in which a stack of sheets Sb made up of a plurality of sheets is stopped and supported by the stacker 105. The stop position in the conveyance direction of the sheet bundle Sb is adjusted by the stacker 105 so that the target folding position α of the sheet bundle Sb is located at a position J facing the front end of the pushing plate 102.
FIG. 5B is a diagram illustrating a state at the time when the first folding operation (first folding operation) for folding the sheet bundle Sb at the target folding position α is started.

With the start of the first folding operation, the pushing plate 102 starts to move from the standby position toward the nip 2 between the rotating folding rollers 1A and 1B. Hereinafter, this start time is referred to as the start time of the first folding operation. Note that the rotation of the folding rollers 1A to 1C may be started simultaneously with the start of the first folding operation, but may be started before that.
FIG. 5C is a diagram illustrating a state in which the sheet bundle Sb is pushed into the nip 2 between the rotating folding rollers 1A and 1B by the pushing plate 102. FIG. By the pushing operation of the pushing plate 102, when the target folding position α in the sheet bundle Sb passes through the nip 2, it is folded in two by the pressure contact force of the rollers 1A and 1B, and in the folded state, the fold line starts. Are conveyed at a conveying speed V by folding rollers 1A and 1B.

When the target folding position α of the sheet bundle Sb moves to the position where it is pulled into the nip 2, the pushing plate 102 switches back and returns to the standby position.
FIG. 5D is a diagram illustrating a state at the time when the second folding operation for folding the sheet bundle Sb at the target folding position β is started after the elapse of a predetermined time T from the start of the first folding operation.
With the start of the second folding operation, the pushing plate 103 starts to move from the standby position toward the nip 3 between the rotating folding rollers 1B and 1C (start of the second folding operation).

For a predetermined time T, if the movement of the pressing plate 103 is started when the predetermined time T has elapsed from the start of the first folding operation, the sheet stack Sb is pushed by the pressing plate 103 into the nip 3 by the pressing operation of the sheet stack Sb. This is the time at which the upper target folding position β is first drawn into the nip 3, and a different time is predetermined according to the number of sheets as will be described later.
FIG. 5E is a diagram illustrating a state in which the sheet bundle Sb is pushed into the nip 3 between the rotating folding rollers 1B and 1C by the pushing plate 103. FIG. As a result of the pushing operation of the pushing plate 103, the target folding position β in the sheet bundle Sb is folded by the pressing force of the rollers 1B and 1C when passing through the nip 3, and the folding roller 1B and 1C lowers the fold at the head. It is conveyed to.

  FIG. 5F shows a state in which the sheet bundle Sb after being folded by the second folding operation has passed through the nip 3 between the folding rollers 1B and 1C. Thereby, the folding in three is completed, and the folded sheet bundle Sb is discharged to the post-processing tray 19 via the transport path Pc shown in FIG. When the target folding position β of the sheet bundle Sb moves to the position where it is pulled into the nip 3, the pushing plate 103 is switched back and returned to the standby position. When the folding is finished, the rotation of the folding rollers 1A to 1C is stopped.

In this way, if the second folding operation is performed after the elapse of the predetermined time T triggered by the start of the first folding operation, for example, the front end of the sheet bundle Sb folded by the first folding operation is detected by a sensor. Compared with the configuration in which the second folding operation is started upon the detection, there is an advantage that the device configuration can be simplified because the detection sensor is not required to be arranged.
However, even if the configuration of the apparatus can be simplified, if the predetermined time T is made constant regardless of the number of sheets in the sheet bundle, the problem described in the section “Problems to be solved by the invention”, that is, trifolding is performed. A similar problem arises in that the width of the sheet bundle after being arranged becomes uneven depending on the number of sheets.

Therefore, in this embodiment, by setting in advance a predetermined time T corresponding to the number of sheets in the sheet bundle, the width of the sheet bundle after being folded in three is prevented from becoming uneven.
Hereinafter, the reason why the same problem as described above occurs will be described with reference to FIG. 6, and the reason why this problem can be solved by the configuration of the present embodiment will be described with reference to FIG.
FIG. 6A is a diagram illustrating a state at the start of the first folding operation when the sheet S is folded in three and the sheet bundle Sb is folded in three. The pushing plate 102 starts moving from the same standby position at the same speed for both the sheet S and the sheet bundle Sb, so that when the sheet S is pushed into the nip 2 between the rollers 1A and 1B. Is the reference time, among the plurality of sheets constituting the sheet bundle Sb, when the sheet S1 closest to the nip 2 is pushed into the nip 2, the thickness D of the sheet bundle Sb before folding (the respective sheets S are It becomes faster than the reference time by the amount of the thickness in the close contact state.

The fact that the sheet S1 of the sheet bundle Sb is pushed into the nip 2 earlier than the single sheet S means that the timing of passing through the nip 2 is also earlier for the sheet S1 than for the single sheet S. Means that.
Therefore, as shown in FIG. 6B, for example, when comparing a state in which the sheet S and the sheet bundle Sb are conveyed after the time T0 has elapsed since the start of the first folding operation, the leading end of the sheet bundle Sb in the conveyance direction is compared. Sd is ahead of the front end Sc in the transport direction of a single sheet S by a substantially thickness D.

In such a state, the second folding operation by the push-in plate 103 is started 3 at the same timing for each of the sheet S and the sheet bundle Sb, for example, when the time T0 has elapsed from the start of the first folding operation. If folded, as shown in FIG. 6C, the width of the sheet bundle Sb after being folded in three is wider than the width L of one sheet S by twice the thickness D of the sheet bundle. .
The thickness of the sheet bundle Sb varies depending on the number of sheets. As the number of sheets increases, the width of the sheet bundle Sb after being folded in three becomes wider than the width L of one sheet after being folded in three. Depending on the number of sheets, the width of the sheet bundle after being folded in three becomes uneven.

  FIG. 7A is a diagram illustrating a state at the start of the second folding operation in the present embodiment. In the present embodiment, the second folding operation is performed for a predetermined time T1 (<T0) from the start of the first folding operation. ). The predetermined time T1 is shorter than the predetermined time T0 for one sheet S, and is a value obtained by dividing a value obtained by doubling the thickness D of the sheet bundle Sb by the conveyance speed V of the sheet bundle Sb from the predetermined time T0. This is equivalent to the time minus.

The second folding operation for the sheet bundle Sb is started earlier than the second folding operation for one sheet S by the difference between the predetermined times T0 and T1, which means that the sheet bundle Sb is one sheet by the second folding operation. The paper sheet S is folded at a position closer to the leading end (fold line Sd) in the transport direction by a distance that is twice the thickness D of the sheet bundle Sb.
That the folding position of the sheet bundle Sb by the second folding operation is closer to the leading end in the transport direction by a distance twice the thickness D than the folding position of one sheet S means that the target folding position α with respect to the sheet bundle Sb. , Β is shorter than the distance between the target folding positions α, β for one sheet S, but the reduced amount corresponds to the doubled thickness D of the sheet bundle Sb. Is equivalent to

Therefore, after being folded in three, the width of the sheet bundle Sb becomes substantially the same as the width L of one sheet S as shown in FIG. 7B, and the width of the sheet after being folded in three can be made uniform. it can.
In order to align the sheet width after being folded in three in this way, it is necessary to set the predetermined time T to a time suitable for the thickness D depending on the thickness D of the sheet bundle Sb. In the present embodiment, the predetermined time T suitable for the number of sheets is obtained in advance through experiments or the like, and timing information that associates the number N of sheets with the predetermined time T is obtained in the timing table 56. The stored timing information is read out when the trifold function is executed.

FIG. 8 is a diagram for explaining an example of the contents of the timing information stored in the timing table 56.
As shown in the figure, the timing information has such a relationship that the predetermined time T gradually decreases as the number of sheets N increases by one, based on the time T1 when the number of sheets N is one. The length of the predetermined time T is determined so that the sheet width after the printing is the same regardless of the number of sheets.

Since the time T1 for the reference sheet S is a factor that determines the sheet width after the folding, the time T1 for the target value L of the sheet width is determined first, and the number of sheets is determined based on the time T1. It can be determined from experiments how much the time T is gradually reduced as the number increases.
The timing information is not limited to information in which the number N of sheets and the predetermined time T are associated with each other, and may be, for example, the following (Expression 1).

Predetermined time T = T1− (k × N) (Formula 1)
Here, k is a sheet bundle included in the width of the sheet bundle after being folded in three so that the width of the sheet bundle after being folded in three is the same even if the number (thickness) of the sheet bundle is different. Is a coefficient for correcting the number of sheets (thickness), and is determined in advance by experiments or the like. If this (Equation 1) is used, there is no need to store information in a table format.

(5) Processing Contents of Tri-Fold Control when Folding Sheet Bundle in Three FIG. 9 is a flowchart showing the processing contents of tri-fold control executed by the control unit 20.
As shown in the figure, the number of sheets of the sheet bundle Sb to be tri-folded is acquired (step S1). The number of sheets is acquired from the sheet information from the image forming apparatus 8.

It is confirmed that all the obtained number of sheets are stored in the stacker 105 (step S2) (FIG. 5A). The confirmation that all the sheets of paper have been received is performed by receiving detection signals output from the sheet leading edge detection sensor 106 by detecting the leading edge of each sheet for the acquired number of sheets.
When it is confirmed that all the sheets of paper are stored in the stacker 105, the first folding operation is started (step S3) (FIG. 5B). The first folding operation is executed by the push plate drive control unit 55. By the first folding operation, the sheet bundle is folded at the target folding position α (FIG. 5C).

Simultaneously with the start of the first folding operation, the timer 57 starts measuring time (step S4).
The start timing of the second folding operation is acquired (step S5). This acquisition is performed by referring to the timing information stored in the timing table 56 and reading a predetermined time T corresponding to the number of sheets acquired in step S1.
When it is determined that the count value of the timer 57 has reached the read predetermined time T (“YES” in step S6), the second folding operation is started (step S7) (FIG. 5D). The second folding operation is executed by the push plate drive control unit 55.

The sheet bundle Sb is folded at the target folding position β by the second folding operation (FIG. 5E), and then discharged to the post-processing tray 19 (FIG. 5F).
After the timer 57 stops counting and the count value is reset to 0 (step S8), the process ends. Each time the tri-fold function for one sheet bundle is executed, the process is repeatedly executed.

As described above, in the present embodiment, the start time of the second folding operation is set in advance at a timing suitable for the number of sheets according to the number of sheets in the sheet bundle. Even if is changed, the sheet width after being folded in three can be made the same.
The present invention is not limited to a sheet folding apparatus, and may be a sheet folding method for folding a sheet. The method may be a program executed by a computer. The program according to the present invention can be read by a computer such as a magnetic disk such as a magnetic tape or a flexible disk, an optical recording medium such as a DVD-ROM, DVD-RAM, CD-ROM, CD-R, MO, or PD. It can be recorded on various recording media, and may be produced, transferred, etc. in the form of the recording medium, or in the form of a program, including wired and wireless networks including the Internet, broadcasting, telecommunications lines, In some cases, the data is transmitted and supplied via satellite communication or the like.

(Modification)
As described above, the present invention has been described based on the embodiment. However, the present invention is not limited to the above-described embodiment, and the following modifications may be considered.
(1) In the above embodiment, the predetermined time T is shortened every time the number of sheets in the sheet bundle is increased (in accordance with the difference in the number of sheets), but is not limited to one sheet.

The predetermined time T may be shortened (the second folding operation is started earlier) as the number of sheets in the sheet bundle increases. For example, a sheet bundle made up of two to five sheets is predetermined. If the time is Ta and the sheet bundle is composed of 6 to 10 sheets, the predetermined time is Tb (<Ta), etc., and a plurality of sheets are set as one unit, and the predetermined time T is gradually decreased for each unit. You can also.
Thus, if the predetermined time is varied in units of a plurality of sheets, among the plurality of sheets, for example, a sheet bundle made up of 6 sheets and a sheet bundle made up of 10 sheets, the thickness of the sheet due to the difference in the number of sheets. Although the paper width after being folded in three is slightly changed, the effect that the paper width can be made uniform can be obtained as compared with the configuration in which the predetermined time T is uniform for any number of paper sheets. The relationship between the number of sheets and the predetermined time is determined so that the sheet width after being folded in three is constant regardless of the number of sheets.

  (2) In the above embodiment, the configuration example in which the number of sheets is used as an index for the thickness D of the sheet bundle has been described. However, the present invention is not limited to this. For example, if the basis weight of the sheets is different, the number of sheets constituting the sheet bundle is different even if the thickness of the sheet bundle is the same. In other words, if the basis weight of the paper is different, the thickness of the paper bundle is different even with the same number of sheets. Specifically, even if the number of sheets is five, a sheet bundle made of thick paper may be thicker than a sheet bundle made of ten thin sheets.

In such a case, the thickness of the sheet bundle can be obtained from the number of sheets and the basis weight, and a predetermined time T suitable for the obtained thickness of the sheet bundle can be obtained.
For example, if the timing information in which the basis weight, the number of sheets, and the predetermined time T are associated with each other is generated in advance, the predetermined time T for a sheet bundle of N sheets of basis weight X can be acquired. Specifically, in the timing information of FIG. 8, the time tn corresponding to the number of sheets n is set to a time suitable for the basis weight, for example, the time tn1 with respect to the basis weight A, according to the difference in basis weight of the sheet. A configuration in which a time tn2 or the like different from the time tn1 is determined for the basis weight B can be adopted.

The basis weight of the paper can be acquired from the paper information if it is included in the paper information from the image forming apparatus 8.
Instead of the basis weight of the sheet, for example, a type of sheet, specifically, a type such as thick paper or thin paper can be acquired. The thickness information can be replaced with information in which the paper type, the number of paper sheets, and the predetermined time T are associated with each other, and the paper type can be acquired from the paper information.

Further, it is possible to adopt a configuration in which the coefficient k in the above (Equation 1) is switched to a value suitable for the basis weight or type according to the basis weight or type of the paper. Even if the number of sheets is the same, the start timing of the second folding operation is varied depending on the basis weight and type of the sheet.
Further, information indicating the thickness of the sheet bundle before being folded may be acquired from the image forming apparatus 8. If the thickness D of the sheet bundle can be acquired, the following (Expression 2) can be used instead of (Expression 1).

Predetermined time T = T1− (k × D) (Formula 2)
From this, it can be said that the information indicating the thickness of the sheet bundle includes the number of sheets constituting the sheet bundle, the basis weight, the type, or the thickness of the sheet bundle itself. Based on the information indicating the thickness of the sheet bundle, the second folding operation is started at the first time when the thickness of the sheet bundle is the first thickness, and the second thickness is larger than the first thickness. In addition, it is possible to perform control that starts at the second time point earlier than the first time point by a predetermined time (corresponding to t2, t3, etc. in FIG. 8) according to the difference between the first and second thicknesses.

It is also possible to adopt a configuration in which the predetermined time T set according to the thickness of the sheet bundle is further corrected.
That is, the thick paper is usually more rigid than the thin paper, and after being folded in two by the first folding operation, it is easier to open than the thin paper to return to the original straight posture before folding.
For this reason, after a sheet bundle of a plurality of thick papers is folded at the target folding position α by the first folding operation, the nth thick paper folds overlap the nth thick paper (n + 1). ) It is easy to leave a gap in the conveying direction between the folds of the thick paper sheets, and the thickness of the folds of the paper bundle (corresponding to the thickness D shown in FIG. 7B) is larger than that of the thin paper bundle. There are many cases.

Therefore, for a sheet bundle made of thick paper, even when the thickness of the sheet bundle before folding is the same as that of the sheet bundle made of thin paper, the start of the second folding operation is made earlier than in the case of the sheet bundle made of thin paper. By performing the control, when different types of paper are used, the widths of the paper bundle after being folded in three can be made more uniform.
In the case of this configuration, for example, in the case of thick paper, it is possible to perform processing for correcting the coefficient k in (Equation 2) to a value larger than the value for thin paper. Further, the coefficient k may be corrected for each sheet type such as thick paper, plain paper, and thin paper, and the start timing of the second folding operation may be varied depending on the sheet type.

The thickness of paper such as thick paper and thin paper is not limited to the paper type, and can be determined by basis weight, for example. This is because the thickness of the paper generally increases as the basis weight increases. From this, the paper type and the basis weight can be regarded as information indicating the thickness of one sheet (sheet).
The information such as the number of sheets, the basis weight, the type, and the thickness of the sheet bundle is not limited to the configuration acquired from the image forming apparatus 8. For example, when an operation unit is arranged in the sheet post-processing apparatus 1, the operation is performed. It can also be obtained by accepting input of information by the operator via the unit.

(3) In the above-described embodiment, the second folding operation is started when the predetermined folding time T elapses from the start of the first folding operation when the three-fold function is executed. Any configuration may be used as long as the operation is triggered by some event.
For example, a sheet bundle conveyed to the top after being folded in the first folding operation is detected by a detection unit such as a detection sensor, and the second folding operation is performed when a predetermined time T has elapsed since the detection. A configuration that starts the process is conceivable.

With this configuration, it is necessary to separately arrange a detection unit. However, the position of the sheet bundle being conveyed on the conveyance path Pd on the conveyance path Pd is directly detected, and the movement of the pushing plate 103 is started. be able to.
Since the position of the sheet bundle on the conveying path Pd is detected, the moving speed of the pressing plate 102 fluctuates in the first folding operation before entering the conveying path Pd although it is a minute range. Even if the pushing timing of the sheet bundle due to the pressing of the folding rollers 1A and 1B into the nip 2 varies, the variation does not affect the detection result.

Therefore, the folding position of the sheet bundle by the push-in plate 103 does not vary due to the influence of the variation, and the second folding position of the sheet bundle by the second folding operation deviates from the target and the positional accuracy is lowered. Can be prevented.
(4) In the above-described embodiment, an example in which tri-folding is performed, so-called three-fold folding, has been described, but tri-folding is not limited to this. For example, the present invention can also be applied to a so-called outer three-fold (Z-fold).

  When applied to Z-folding, instead of the configuration of FIG. 3, the folding roller 1A is disposed below the folding roller 1B and faces the nip 2 with the folding roller 1A disposed below the folding roller 1B. The pushing plate 102 is disposed at a position where the pushing plate 103 is disposed, the pushing plate 103 is disposed below the nip 3 between the folding rollers 1B and 1C, and moves from the bottom toward the nip 3. The start of the second folding operation by the push-in plate 103 is performed when the predetermined time T has elapsed, similarly in the case of Z folding.

(5) In the above embodiment, the sheet bundle Sb after being folded in the first folding operation is conveyed in the conveyance direction (first direction) by the pair of folding rollers 121 at the top of the fold, and the sheet bundle Sb. However, the present invention is not limited to this.
For example, instead of the above configuration, the sheet bundle Sb after being folded by the first folding operation is conveyed in the second direction opposite to the first direction with the fold as the rear end side, and the sheet bundle is conveyed. It is also possible to adopt a configuration in which Sb is folded in the second folding operation to be folded in three.

In the case of adopting the configuration of transporting in the second direction, the start timing of the second folding operation is set later as the thickness of the sheet bundle becomes thicker, contrary to the above embodiment. Specifically, in the timing information shown in FIG. 8, for example, when the number of sheets in the sheet bundle is 2, for example, the predetermined time T is (T1 + t2), and when the number is N, the predetermined time T is (T _n-1 + tn). ).
(6) In the above-described embodiment, an example has been described in which the sheet folding apparatus is applied to a sheet post-processing apparatus that folds a sheet bundle composed of sheets such as a plurality of sheets output from the image forming apparatus 8. The sheet output device is not limited to the sheet output from the image forming apparatus 8 and can be generally applied to a sheet folding apparatus that folds a sheet bundle in three.

Moreover, although the example which uses a pushing board as a pushing member which pushes in a sheet | seat bundle was demonstrated, it is not restricted to plate shape, For example, you may use a linear member.
Further, the folding rollers 1A and 1B pressed against each other are the folding roller pair 121, the folding rollers 1B and 1C pressed against each other are the folding roller pair 122, and the folding roller 1B is one of the folding roller pair 121 and the folding roller pair 122. However, the present invention is not limited to this, and each of the folding roller pair 121 and the folding roller pair 122 may be composed of two separate rollers.

In addition, the configuration example in which the pair of folding rollers 121 and 122 is used as a rotating body pair for performing the folding operation and conveyance of the sheet bundle has been described. However, the rotating body that configures the rotating body pair is not limited to a roller. A shaped member or the like can also be used.
The contents of the above embodiment and the above modification may be combined.

  The present invention can be widely applied to a sheet folding apparatus and a sheet folding method for folding a sheet bundle.

DESCRIPTION OF SYMBOLS 1 Sheet post-processing apparatus 1A, 1B, 1C Folding roller 2, 3 Folding roller pair nip 18 Paper folding part 20 Control part 51 CPU
55 Pushing plate drive control unit 56 Timing table 57 Timer 102, 103 Pushing plate 105 Stacker 107, 108 Pushing plate drive motor N Number of sheets Pa, Pb, Pc Paper conveyance path S Paper Sb Paper bundle T Predetermined time α, β Target folding position

Claims (8)

A sheet folding apparatus that folds a sheet bundle of a plurality of sheets by a first folding operation, and then folds the sheet bundle in three by a second folding operation,
Conveying means for conveying the sheet bundle after being folded in the first folding operation in the first direction with the fold as the head, or conveying the fold in the second direction opposite to the first direction with the fold as the rear end. When,
A pair of rotating bodies arranged in a direction in which the central axis of rotation intersects the conveying direction along the conveying path of the sheet bundle conveyed by the conveying means,
In order to perform the second folding, a pressing member disposed opposite to the pair of rotating bodies with the conveyance path interposed therebetween is moved toward the sheet bundle being conveyed, and is moved to the sheet surface of the sheet bundle. A pushing means for bringing the sheet bundle into contact with the nip of the rotating body pair;
Obtaining means for obtaining information indicating the thickness of the sheet bundle;
As the thickness of the acquired sheet bundle increases, the start timing of the pushing operation by the pushing member with respect to the sheet bundle becomes earlier when the sheet bundle is conveyed in the first direction, or the sheet bundle becomes Control means for controlling the pushing means so as to be slow when transported in the second direction;
A sheet folding apparatus comprising: The control means performs the pushing operation,
Starting at the first time when the thickness of the sheet bundle is the first thickness,
In the case of a second thickness that is greater than the first thickness,
When the sheet bundle is conveyed in the first direction, the sheet bundle starts at a second time point earlier than the first time point by a predetermined time according to the difference between the first and second thicknesses, or
2. The sheet folding apparatus according to claim 1, wherein when the sheet bundle is conveyed in the second direction, the sheet folding apparatus starts at a second time point that is later than the first time point by the predetermined time. Information indicating the thickness of the sheet bundle is information indicating the number of sheets,
The control means includes
The pushing operation is
If the acquired number of sheets is the first number corresponding to the first thickness, the process starts at the first time point. If the acquired number of sheets is the second number corresponding to the second thickness, the process starts at the second time point. And
The predetermined time is:
The sheet folding apparatus according to claim 2, wherein the time is determined according to a difference between the first and second number of sheets. The acquisition means includes
Furthermore, information indicating the sheet type or basis weight is acquired,
For the first sheet number, for each different sheet type or basis weight, a different value corresponding to the sheet type or basis weight is determined.
For the second sheet number, for each different sheet type or basis weight, a different value corresponding to the sheet type or basis weight is determined,
The control means includes
4. The sheet folding apparatus according to claim 3, wherein each of the first and second number of sheets is set to a value corresponding to the obtained sheet type or basis weight. The first time point is
It is when the first predetermined time has elapsed since the execution of the first folding operation,
The second time point is
When the sheet bundle is conveyed in the first direction, when the second predetermined time is a time obtained by subtracting the predetermined time from the first predetermined time, the first folding operation is performed from the first folding operation. 2 When a predetermined time has passed, or
In the case where the sheet bundle is conveyed in the second direction, when a time obtained by adding the predetermined time from the first predetermined time is defined as a second predetermined time, the first folding operation is performed. The sheet folding device according to any one of claims 2 to 4, wherein the second predetermined time has elapsed. A rotating body pair different from the rotating body pair;
In order to perform the first folding, a pressing member different from the pressing member is moved toward the sheet bundle before being folded and brought into contact with the sheet surface of the sheet bundle, and the sheet bundle is A pushing means different from the pushing means for pushing into a nip of another rotating body pair,
The first time point is
The sheet folding apparatus according to claim 5, wherein the first predetermined time has elapsed since the start of the pressing operation by the another pressing member. The acquisition means includes
In addition, information indicating the thickness of one sheet is acquired,
The control means includes
When the thickness of the first sheet bundle is the same as the thickness of the second sheet bundle made of a sheet that is thicker than the sheets constituting the first sheet bundle, the pushing operation by the pushing member with respect to the second sheet bundle When the sheet bundle is conveyed in the first direction earlier than the start timing of the pushing operation by the pushing member with respect to the first sheet bundle, or when the sheet bundle is conveyed in the second direction. The sheet folding apparatus according to claim 1, wherein the sheet folding apparatus is delayed. A sheet folding method in a sheet folding apparatus for folding a sheet bundle of a plurality of sheets by a first folding operation and then folding the sheet bundle by a second folding operation.
Conveying step of conveying the sheet bundle after being folded by the first folding operation in the first direction with the fold as the head, or conveying the fold in the second direction opposite to the first direction with the fold as the rear end. When,
An acquisition step of acquiring information indicating the thickness of the sheet bundle;
In order to perform the second folding, a pressing member disposed opposite to the pair of rotating bodies across the conveyance path of the sheet bundle to be conveyed is moved toward the sheet bundle so as to be on the sheet surface of the sheet bundle. A control step for controlling the pushing means for performing an operation of pushing the sheet bundle toward the nip of the pair of rotating members, and
In the control step,
As the thickness of the acquired sheet bundle increases, the start timing of the pushing operation by the pushing member with respect to the sheet bundle becomes earlier when the sheet bundle is conveyed in the first direction, or the sheet bundle becomes A sheet folding method, wherein control is performed so that the sheet is slowed when conveyed in the second direction.

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