JP7308029B2 - SHEET PRESSING DEVICE AND IMAGE FORMING SYSTEM INCLUDING THE SAME - Google Patents

Description

The present invention relates to a sheet pressing device for folding a sheet and an image forming system such as a copying machine, a printer, a facsimile machine, or a multi-functional machine equipped with the same.

Conventionally, in a sheet folding processing device (post-processing device) installed in an image forming system such as a copier or a printer, the increase in the thickness (folding height) of the crease formed on the sheet due to the folding process has been prevented. For the purpose of preventing this, there is known a method in which a sheet is once folded by a folding unit to form a fold line, and then the fold line is further pressed by another pressing member (additional folding process).

For example, Japanese Patent Application Laid-Open No. 2002-100001 discloses that an additional folding mechanism configured by a plurality of pairs of rollers is arranged in parallel with the pair of folding rollers downstream of a pair of folding rollers that fold the sheet. A sheet processing apparatus is disclosed that performs additional folding without increasing the processing time by continuously applying a load to a folding portion (folding line) with a plurality of pairs of rollers.

Further, Japanese Patent Application Laid-Open No. 2002-200002 discloses a folding roller that folds a sheet while passing through a nip of a pair of rollers, and a folding section between a lower guide plate and a folding section of the folded sheet. A sheet processing apparatus is disclosed which is provided with a fold-enhancing roller for further folding the paper, and which is moved in a direction orthogonal to the paper-conveying direction.

JP 2012-153525 A JP-A-2004-59304

In the sheet processing apparatus disclosed in Patent Document 1 described above, since a plurality of pairs of rollers of the additional folding mechanism are arranged in parallel with the pair of folding rollers, the direction of the fold of the sheet and the rotation of the rollers for additional folding are determined. The direction in which the axis extends is the same, and from the viewpoint of crushing the fibers in the crease, the effect of additional folding is reduced compared to the method of additionally folding by moving a repressurizing means such as a roller along the crease. There is a problem.

Further, the paper processing apparatus disclosed in Patent Document 2 described above presses the crease while moving the fold-enhancing roller in the direction orthogonal to the paper conveying direction, so the additional folding method disclosed in Patent Document 1 Compared to , additional folding can be performed efficiently. However, since the effect of additional folding, that is, reinforcement of the crease is obtained by crushing the fibers of the crease, the pressing force exerted by the rotating roller has a large effect. In the case of a sheet in which a plurality of sheet portions partitioned by a plurality of folds are folded through the folds, such as Z-folding, there are cases where the fold-enhancing roller directly contacts the folds and between the fold-enhancing rollers and the folds. There may be cases where the sheet portion is interposed in the In the sheet folding apparatus disclosed in Patent Document 2, pressure is applied under the same conditions regardless of whether or not the sheet portion is interposed between the fold-enhancing roller and the fold-enhancing roller. If the sheet portion is interposed between the fold-enhancing rollers, the pressing force of the fold-enhancing roller is dispersed among the sheet portions, and the pressing force acting on the fold is weakened. Therefore, there is a problem that the effect of the additional folding varies depending on the positional relationship between the additional folding roller, the fold line, and the sheet portion, resulting in a change in the folding height.

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to solve the problems existing in the prior art by determining whether or not a roller for additional folding is in direct contact with the fold of a sheet during additional folding. It is about restraining change.

In view of the above object, as a first aspect, the present invention provides a first crease and a second crease formed between a first edge and a second edge opposite to the first edge. A sheet pressing device for performing additional folding on a sheet folded in a Z-shape by a fold line, comprising: a first portion between the first fold line and the second fold line; the folded sheet divided into a second portion between the fold and the first edge, and a third portion between the second edge and the second fold, the first portion The second part faces the first surface of the first part, and the third part faces the second surface opposite to the first surface of the first part. a conveying means for conveying so as to overlap ; a pressing roller for pressing the folded sheet by rotating around a rotation axis extending in a conveying direction of the conveying means ; and a facing member arranged to face the pressing roller. and a first position that presses the folded sheet positioned between the pressing roller and the opposing member , and a first position that moves away from the opposing member in the thickness direction of the sheet pressed at the first position. a first moving mechanism capable of moving the pressing roller between two positions and adjusting a pressing force against the sheet pressed between the pressing roller and the opposing member; In a state in which the pressing roller is moved to the first position with respect to the opposing member , the pressing roller is moved along the direction intersecting the conveying direction so as to press the first fold line or the second fold line. and a second moving mechanism for moving the folded sheet by the second moving mechanism, wherein the conveying means moves the folded sheet such that the second portion faces the pressing roller and the third portion faces the facing member. When the sheet is conveyed and the second fold is positioned between the pressing roller and the opposing member, the pressing force applied to the folded sheet between the pressing roller and the opposing member is When the first fold is located between the pressing roller and the opposing member, the pressing force between the pressing roller and the opposing member is stronger than the pressing force applied to the folded sheet . To provide a sheet pressing device for

In the above-described sheet pressing device, a crease formed in advance in the carried-in sheet is arranged between the additional folding roller and the pedestal, and the additional folding roller is moved to the pedestal along the crease while being moved to the pressing position. Additional folding of the fold line of the sheet can be performed by moving the folding member. Direct contact with the rotating additional folding rollers crushes the fibers in the folds, so the additional folding effect is high. The pressure is distributed among the sheet portions and the pressing force acting on the crease is weakened. However, in the above-described sheet pressing device, when the sheet portion is positioned between the additional folding roller and the fold line, the crease is applied between the additional folding roller and the pedestal more than when the additional folding roller and the fold line are directly opposed to each other. Therefore, the pressing force applied to the fold when the sheet portion is interposed between the additional folding roller and the fold line is applied to the sheet portion between the additional folding roller and the fold line. It is suppressed that the pressing force becomes weaker than the pressing force that is applied when there is no intervention.

In the sheet pressing device, the first moving mechanism includes an interval adjusting mechanism, and the control section controls the interval adjusting mechanism to change the interval between the additional folding roller and the base at the pressing position. You may make it change pressing force by changing. By changing the distance between the additional folding roller and the pedestal by means of the distance adjusting mechanism, the pressing force applied to the fold can be varied between the pressing force and the pedestal.

Further, the first moving mechanism includes an interval adjusting mechanism, and at least one of the additional folding rollers and the pedestal has a support portion that supports the additional folding rollers or the pedestal, and a support portion that moves toward the seat with respect to the support portion. an urging portion that urges the additional folding rollers or the pedestal toward the sheet, and the control portion controls the interval adjustment mechanism to change the interval between the support portion and the sheet at the pressing position. You may make it change pressing force by changing. With this configuration, by changing the distance between the pedestal and the additional folding roller, the amount of compression of the urging portion at the pressing position changes and the urging force changes. It is possible to reliably change the pressing force to be applied to the crease between them.

Further, in the above-described sheet pressing device, when the sheet portion is positioned between the additional folding roller and the fold line, the control section is configured to press the pressing position higher than when the additional folding roller and the fold line are directly opposed to each other. The second moving mechanism may be controlled so as to slow down the speed at which the additional folding roller is moved along the fold. By controlling the second moving mechanism with the control unit in this way, the work applied to the fold between the additional folding roller and the fold when the sheet portion is positioned between the additional folding roller and the fold is When the additional folding roller and the crease directly face each other, the amount of work applied to the crease between the additional folding roller and the pedestal is greater than the amount of work applied to the crease. The effect of the resulting reduction in pressing force is compensated for by the increase in applied work.

Further, the sheet pressing device further includes sheet basis weight recognition means for acquiring information about the basis weight of the sheet, and the control unit controls the sheet portion to be positioned between the additional folding roller and the fold line, and the sheet to be folded. When the basis weight of the sheet acquired by the basis weight recognition means is lower than a predetermined value, than when the basis weight of the sheet acquired by the sheet basis weight recognition means is equal to or greater than the predetermined value, The first moving mechanism may be controlled so as to weaken the pressing force applied to the fold between the additional folding roller and the pedestal. When the basis weight of the sheet is small and the sheet portion is positioned between the additional folding roller and the fold line, the additional folding roller presses the fold line so that the sheet portion sandwiched between the additional folding roller and the fold line is folded. marks tend to remain. However, by performing the control as described above, it is possible to suppress the crease marks from remaining.

Further, according to a second aspect of the present invention, there is provided an image forming apparatus that forms an image on a sheet and carries out the sheet on which the image is formed, and a sheet processing apparatus that folds the sheet carried out from the image forming apparatus. and the sheet pressing device described above.

According to the present invention, when the sheet portion is positioned between the additional folding roller and the fold line, the pressing force applied to the fold between the additional folding roller and the base is greater than when the additional folding roller and the fold line face each other directly. Therefore, when the sheet portion is interposed between the additional folding roller and the fold line, the pressing force applied to the fold is It is suppressed from becoming weaker than the applied pressing force. Therefore, fluctuations in the additional folding effect due to the positional relationship between the additional folding rollers, the folds, and the sheet portion are suppressed, and the folds with a more uniform folding height are produced regardless of the positional relationship between the additional folding rollers, the folds, and the sheet portion. Realization is possible.

1 is an overall configuration diagram of an image forming system provided with a sheet pressing device of the present invention; FIG. 2 is an explanatory view showing main parts of a folding mechanism and an additional folding unit (corresponding to a sheet pressing device) of the folding device shown in FIG. 1; FIG. FIG. 2 is a view of the additional folding unit of the folding processing apparatus shown in FIG. 1 as seen from the discharge port side; FIG. 4 is an explanatory view showing a mechanism provided inside the additional folding unit shown in FIG. 3 and urging the additional folding roller toward the sheet; FIG. 10A is an explanatory view showing the operation of the additional folding section when performing the additional folding process on the sheet in the additional folding unit; (b) is a state in which the additional folding roller is moved to the pressing position and the first fold of the sheet is pressed by the additional folding roller; (c) is the first sheet in the pressing position shown in (b); (d) shows a state in which the additional folding roller is moved along the fold line (d), and the additional folding roller is moved to the first retracted position from the state shown in (c). FIG. 12E is an explanatory view showing the operation of the additional folding section when performing the additional folding process on the sheet in the additional folding unit; (f) is a state in which the additional folding roller is moved to the pressing position and the additional folding roller presses the second fold of the sheet; (g) is a state in which the sheet is pressed at the pressing position shown in (f); (h) shows a state in which the additional folding roller is moved along the fold line 2, and (h) shows a state in which the additional folding roller is moved to the second retracted position from the state shown in (g). 2 is a flow chart showing the operation of the folding device shown in FIG. 1; FIG. 10A is an explanatory diagram showing the operation of the additional folding unit when performing additional folding processing on the sheet in the additional folding unit; b) is a state in which the first fold on the leading end side of the sheet in the conveying direction is pressed between the additional folding roller and the pedestal; It shows the state moved to the position. FIG. 10D is an explanatory view showing the operation of the additional folding section when performing additional folding processing on the sheet in the additional folding unit; (e) is a state in which the second fold on the rear end side of the sheet in the conveying direction is pressed between the additional folding roller and the pedestal; It shows a state in which it has been moved to the retracted position. 3 is a schematic diagram showing a first modification of the additional folding unit shown in FIG. 2; FIG. 3 is a schematic diagram showing a second modification of the additional folding unit shown in FIG. 2; FIG.

Preferred embodiments of the present invention will now be described with reference to the accompanying drawings. In the accompanying drawings, similar components are represented by similar reference numerals.

First, referring to FIG. 1, the overall configuration of an image forming system including a folding device having an additional folding unit, which is a sheet pressing device according to the present invention, will be described. The image forming system includes an image forming apparatus A, a folding apparatus B, and a post-processing apparatus C. A sheet S on which an image has been formed by the image forming apparatus A is folded by the folding apparatus B. After that, in the post-processing device C on the further downstream side, stapling processing, alignment processing, etc. are performed as necessary, and the sheet is discharged to the storage tray 27 on the downstream side. Image forming systems include, for example, copiers, printers, and printing machines of various configurations. The image forming apparatus A, the folding device B, and the post-processing device C will be described in detail below.

[Image forming device]
The image forming apparatus A, as shown in FIG. 1, includes an image forming unit A1, an image reading unit A2, and a document feeding unit A3. The image forming unit A1 includes a paper feeding section 2, an image forming section 3, a paper discharging section 4, and a data processing section 5 in the housing 1 of the apparatus.

The paper feed unit 2 includes a plurality of cassettes 2a, 2b, 2c, and 2d, and each cassette 2a, 2b, 2c, and 2d can store sheets S of different standard sizes that have been selected in advance. . Each of the cassettes 2a, 2b, 2c, and 2d incorporates a separation mechanism for separating the sheets S inside one by one and a sheet feeding mechanism for feeding the sheets S therein. Sheets S stored in the sheet feeding unit 2 having such a configuration are fed to the sheet feeding path 6 in a size designated by a main body control unit (not shown). In the paper feeding path 6, there are conveying rollers 7 arranged in the middle and conveying the sheets S supplied from the plurality of cassettes 2a, 2b, 2c and 2d to the downstream side, and conveying rollers 7 arranged at the end of the path for conveying the respective sheets S to the leading edge. A registration roller 8 for aligning is provided, and the sheet S whose leading edge is aligned by the registration roller 8 is fed to the image forming section 3 on the downstream side at a predetermined timing.

The image forming section 3 may be configured to form an image on the sheet S sent from the paper feeding section 2, and various image forming mechanisms can be employed. In the illustrated embodiment, the image forming station 3 is shown as an electrostatic image forming mechanism. However, the image forming unit 3 is not limited to the illustrated electrostatic image forming mechanism, and may employ an ink jet image forming mechanism, an offset image forming mechanism, or the like.

The image forming unit 3 shown in FIG. 1 includes a photoreceptor 9 (drum, belt) and a light emitter 10 for emitting an optical beam to the photoreceptor 9. A developing device 11 (developer) and a cleaner are provided. (not shown) are arranged around the rotating photoreceptor 9 . The illustrated one is a monochrome printing mechanism, in which a light emitting device 10 optically forms a latent image on a photosensitive member 9, and a developing device 11 adheres toner ink to the latent image. The ink image (ink toner) adhered to the photosensitive member 9 is image-transferred by the transfer charger 12 onto the sheet S sent from the paper supply unit 2. After the image-transferred sheet S is fixed by the fixing roller 13, It is sent to the discharge path 14 . Further, the image forming section 3 is provided with a circulation path 17, and after the sheet S from the discharge path 14 is turned upside down in a switchback path, it is sent again to the registration rollers 8, and an image is formed on the back side of the sheet S. is removed and sent to the discharge path 14 . A paper discharge roller 15 is arranged in the paper discharge path 14, and a paper discharge port 16 is formed at the end thereof. do.

Above the image forming unit A1 configured as described above, a document reading unit A2 for optically reading a document image formed by the image forming section 3 is provided. A feeding unit A3 is mounted.

The image reading unit A2 includes a first platen 18 and a second platen 19 made of transparent glass, a reading carriage 20, a light source mounted on the reading carriage 20, a photoelectric conversion element 21, mirrors and lenses. The scanning carriage 20 scans the reading carriage 20 along the first platen 18 to apply light from the light source to the image of the document sheet S placed on the first platen 18 . The light reflected from the image on the document sheet S is guided to the photoelectric conversion element 21 by the reduction optical system 22, and the image is read. The photoelectric conversion element 21 converts the image data into an electric signal and transfers it to the image forming section 3 .

The document feeding unit A3 includes a paper feed tray 23, a paper feed path 24, and a paper discharge tray 25, and conveys documents placed on the paper feed tray 23 one by one along the paper feed path 24. Then, it passes over the second platen 19 and is discharged to the discharge tray 25 . When reading a document fed from the document feeding unit A3 and passing over the second platen 19, the reading carriage 20 is previously stopped below the second platen 19, and the reading carriage 20 is stopped above the second platen 19. to generate image data from the image passing through the .

[Post-processing device]
The post-processing device C is connected further downstream of the folding processing device B connected to the image forming device A, and the sheet that has been folded by the folding processing device B or discharged without being subjected to the folding processing. The sheet S is received and subjected to stapling processing, alignment processing, etc. as necessary.

A post-processing path 26 is provided inside the post-processing apparatus C, and post-processing devices (not shown) such as a stapling unit and an alignment unit are arranged along the post-processing path 26 . The post-processing apparatus C receives the sheets S discharged from the image forming apparatus A via the folding processing apparatus B, and if necessary, the received sheets S are stapled by a post-processing apparatus such as a stapling unit or an alignment unit. , alignment processing, etc., the sheet S is discharged and stored in the storage tray 27 .

[Folding device]
The folding device B connected to the image forming apparatus A is a device that receives the image-formed sheet S ejected from the sheet ejection port 16 of the image forming apparatus A and folds the sheet.

FIG. 2 shows the internal configuration of the folding device B. As shown in FIG. The folding device B includes a control unit 140 that controls the operation of the folding device B. Inside the folding device B, a transport path 101 extending in a substantially horizontal direction is provided. On the conveying path 101, one or a plurality of conveying roller pairs 102 and a folding mechanism 103 arranged downstream of the conveying roller pair 102 are provided. An additional folding unit 104 corresponding to the sheet pressing device according to the present invention is further provided at the end of the path 101 . The folding processing apparatus B folds the sheet S transported along the transport path 101 by the folding processing mechanism 103, and then performs additional folding by the additional folding unit 104, thereby performing the folding processing and the additional folding processing. The sheet S can be handed over to the post-processing device C.

As shown in FIG. 1, the transport path 101 is arranged so as to be continuous with the sheet ejection port 16 of the image forming apparatus A, and the sheet S ejected from the sheet ejection port 16 is conveyed through the transport path 101. It can be carried into the folding processing device B. The discharge port of the additional folding unit 104 is also arranged so as to be continuous with the post-processing path 26 of the post-processing apparatus C, and the sheet S discharged from the additional folding unit 104 enters the post-processing apparatus C via the post-processing path 26. It can be brought in.

The conveying roller pair 102 is formed of rubber rollers and includes an upper conveying roller 102a arranged on the upper side and a lower conveying roller 102b arranged on the lower side facing the upper conveying roller 102a. In this embodiment, the upper conveying roller 102a is connected to a conveying roller drive motor (not shown) and is rotated as the conveying roller drive motor rotates, while the lower roller 102b is connected to the conveying roller drive motor (not shown). It is pressed against the upper conveying roller 102a by the urging force of the spring that is not engaged, and rotates in a driven manner. However, the transport roller pair 102 is not limited to the configuration described above as long as the sheet S can be transported, and an appropriate configuration can be adopted.

The folding mechanism 103 is composed of a pair of folding rollers 105 and a veneer 107 . The folding roller pair 105 is formed of rubber rollers, and includes an upper folding roller 105a arranged on the upper side and a lower folding roller 105b arranged on the lower side facing the upper folding roller 105a. The lower folding roller 105b is pressed against the upper folding roller 105a by the biasing force of a spring (not shown), and the upper folding roller 105a and the lower folding roller 105b are driven by a common folding roller drive motor (not shown). They are connected to each other and rotate in opposite directions as the folding roller drive motor rotates. The sliced plate 107 is arranged between the conveying roller pair 102 and the folding roller pair 105 and is connected to a sliced plate driving motor (not shown). It is designed to move parallel to the transport path on the side.

An upper transport guide 108 , a lower transport guide 109 , an upper folding guide 110 , and a lower folding guide 111 are provided on the transport path 101 between the transport roller pair 102 and the folding roller pair 105 .

The upper conveying guide 108 is formed from immediately behind the conveying roller pair 102 to above the thrust plate 107 so as to guide the leading edge of the sheet S from the conveying roller pair 102 to the thrust plate 107 . The upper conveying guide 108 is for regulating the flow of the sheet S conveyed along the conveying path 101, is arranged above the conveying path 101, and has a shape bent downward toward the downstream side. . The upper folding guide 110 is arranged between the upper conveying guide 108 and the folding roller pair 105 , and guides the leading edge of the sheet S and a folded portion of the sheet S to be described later to the folding roller pair 105 . It extends to the front. The upper folding guide 110 is for regulating the flow of the sheet S in the folding mechanism 103 , and is provided downstream of the upper transport guide 108 and above the transport path 101 .

The lower conveying guide 109 is for regulating the flow of the sheet S conveyed along the conveying path 101, and is arranged below the conveying path 101. Like the upper conveying guide 108, the lower conveying guide 109 is arranged downstream. It has a downward curved shape. The lower conveying guide 109 is cut off before the sliced plate 107, and an open space is formed downstream of the lower conveying guide 109. As shown in FIG. The lower folding guide 111 is disposed on the downstream side of the veneer 107 and extends across the upstream and downstream sides of the folding roller pair 105 . The portion has a horizontal surface for guiding the leading edge of the conveyed sheet S and a folded portion of the sheet S, which will be described later, to the nip portion of the folding roller pair 105, and an inclined surface for facilitating the guiding to the horizontal surface.

The sliced plate 107 is moved horizontally by a sliced plate driving device (not shown) and a controller 140 . Also, the thrust plate 107 fills the space between the lower conveying guide 109 and the lower folding guide 111 when the conveying roller pair 102 conveys the sheet S to the folding roller pair 105 along the conveying path 101 . It is arranged so as to guide the leading edge of the conveyed sheet S to the lower folding guide 111 . The folding processing operation by the projecting plate 107 will be described later.

Next, the configuration of the additional folding unit 104 will be described with reference to FIG. The additional folding unit 104 is arranged downstream of the folding roller pair 105 in the sheet S conveying direction. The additional folding unit 104 includes a movable support member 112, a plurality of additional folding rollers 114 supported by the support member 112, and a pressing member arranged to face the plurality of additional folding rollers 114 across the sheet conveying path. A pedestal 141, a regulating member 115 attached to the support member 112, a first moving mechanism 116 for moving the support member 112 in a direction toward and away from the pressing pedestal 141, and a support member 112 horizontally moved to the seat S. and a second moving mechanism 117 for moving along the fold of the . Portions of the upper folding guide 110 and the lower folding guide 111 that face each other vertically and downstream of the folding roller pair 105 function as a pair of carry-in guides 118 that guide the sheet S into the additional folding unit 104 . , upstream ends of the pair of carry-in guides 118 form a carry-in opening 119 of the additional folding unit 104 . Further, the additional folding portion is configured by the plurality of additional folding rollers 114 supported by the support member 112 as described above and the pressing base 141 .

The plurality of additional folding rollers 114 are arranged so that each of the pressing members can rotate about a rotation axis extending in the conveying direction of the sheet S (the direction parallel to the upper surface of the pressing base 141 and perpendicular to the fold of the sheet S). They are spaced apart from each other at regular intervals along the fold direction of the sheet S and supported by the supporting member 112 . Also, the first moving mechanism moves the support member 112 that supports the plurality of additional folding rollers 114 in a direction toward and away from the pressing base 141 . As a result, the plurality of additional folding rollers 114 are brought closer to and away from the pressing pedestal 141 , and the folds of the sheet S disposed between the additional folding rollers 114 and the pressing pedestal 141 are aligned with the additional folding rollers 114 and the pressing pedestal 141 . and a retracted position where the plurality of additional folding rollers 114 are moved from the pressing position in the direction away from the sheet S. As shown in FIG. Further, the second moving mechanism 117 can move the plurality of additional folding rollers 114 along the folds of the sheet S by moving the support member 112 in the horizontal direction (horizontal direction in FIG. 3) at the pressing position. ing. Note that the plurality of additional folding rollers 114 and the lower folding guide 111 are in direct contact with each other when the sheet S is not interposed between them at the pressing position. The length of the pressing member arrangement area (i.e., the distance between the additional folding rollers 114 arranged at the extreme positions of the pressing member arrangement area) is set so that it is adjacent to one extreme position when moved from the retracted position to the pressing position. One end of the fold of the sheet S (the end on the upstream side of the moving direction of the additional folding roller 114) is arranged between the two additional folding rollers 114 arranged, and the additional folding roller is arranged at the other extreme position. 114 is determined to be positioned on the fold line. Preferably, as in the illustrated embodiment, the length of the pressing member arrangement area, that is, the length between the additional folding rollers 114 arranged at the extreme positions of the pressing member arrangement area, is carried into the additional folding unit 104. 1 pitch of the array of the additional folding rollers 114 (one interval between two additional folding rollers arranged adjacent to each other) is shorter than the length of the fold of the sheet S on which the sheet S is folded. In this case, the number of additional folding rollers 114 required can be reduced, and the cost of the additional folding rollers 114 can be reduced. In addition, since the number of additional folding rollers 114 supported by the support member 112 is reduced, when the same force is applied to the support member 112, the pressing force per additional folding roller 114 against the sheet S is increased. The folding effect is enhanced, and efficient additional folding is possible with a smaller force.

In the additional folding unit 104, the sheet S is placed in the additional folding unit 104 in a state in which the plurality of additional folding rollers 114 are arranged at the retracted position or the receiving position spaced apart from the pressing position to the retracted position with respect to the pressing pedestal 141. accept. Thereafter, the position of the sheet S is detected by sheet position detection means (not shown) provided upstream of the folding roller pair 105, and when the fold of the sheet S reaches below the folding rollers 114, the sheet S is folded. Then, the first moving mechanism 116 moves the plurality of additional folding rollers 114 to the pressing position with respect to the pressing base 141 . When the plurality of additional folding rollers 114 move to the pressing position, one end of the fold (the upstream end in the direction of movement along the fold) of the sheet S is positioned at one extreme position in the pressing member arrangement area. , while the other end of the fold (end on the downstream side in the direction of movement along the fold) is outside the pressing member arrangement area (i.e., the pressing member arrangement area outside of the additional folding roller 114 at the other extreme position in the direction) is carried into the additional folding unit 104 . Further, by moving the plurality of additional folding rollers 114 along the folds of the sheet S with respect to the pressing base 141 at the pressing position by the second moving mechanism 117, the plurality of additional folding rollers 114 fold the sheets S along the folds. Further folding is performed by pressing over the entire area to strengthen the fold.

Further, a regulating member 115 having a substantially L-shaped cross section attached to the support member 112 is disposed outside the additional folding rollers 114 at the extreme positions and between the additional folding rollers 114 that are spaced apart from each other. The regulating member 115 moves the additional folding roller 114 along the fold line of the sheet S at the pressing position against the pressing pedestal 141 to perform additional folding. 141) and the upper surface of the pressing pedestal 141 is the height of a normal transport path, for example, a pair of carry-in guides 118 ( It is arranged at a regulating position that is shorter than the distance d2 between the upper carry-in guide 118a and the lower carry-in guide 118b), and moves along the fold of the sheet S together with the support member 112 while maintaining the distance d1. The distance d1 between the bottom surface of the regulating member 115 and the top surface of the pressing base 141 is determined so that these members do not come into direct contact with each other. As a result, prior to pressing by the additional folding rollers 114, the regulating member 115 pushes down the fold to be lower than the height between the upper carry-in guide 118a and the lower carry-in guide 118b. Additional folding can be performed by pressing the crease.

Note that the gaps between the plurality of additional folding rollers 114 and the pressing base 141 and the gaps between the regulating member 115 and the pressing base 141 are kept constant over the entire area in the direction along the fold of the sheet S.

As shown in FIG. 4, a plurality of additional folding rollers 114 are rotatably attached to auxiliary members 113 that are movably supported with respect to the support member 112, and formed on the support member 112. Preferably, springs 121 are arranged as elastic members between the spring receiving portion 120 and the upper end of each auxiliary member 113 to urge the additional folding rollers 114 toward the pressing pedestal 141 . With this configuration, when the support member 112 of the additional folding unit 104 and the regulating member 115 attached thereto move downward toward the pressing pedestal 141, the additional folding roller 114 is pushed through the sheet S. When it touches the pressing base 141, it stops moving downward. On the other hand, the support member 112 and the regulating member 115 can continue to move downward due to the contraction of the spring 121, and the distance between the bottom surface of the regulating member 115 and the top surface of the pressing pedestal 141 becomes a desired value. 115 can be stopped when it reaches the regulation position. Further, if each auxiliary member 113 is biased by an individual spring 121, even if the support member 112 is slightly tilted and moves along the fold of the sheet S, the additional folding rollers 114 do not move toward the fold of the sheet S. Therefore, it is possible to prevent uneven additional folding due to a change in the pressing force depending on the crease portion. Further, the additional folding roller 114 is pressed against the sheet S by the compression of the spring 121, and the pressing force can be reliably applied to the fold of the sheet S.

In the illustrated embodiment, the pressing pedestal 141 is arranged in a window portion provided below the plurality of additional folding rollers 114 in the lower folding guide 111, and is included as part of the first moving mechanism 116, which will be described later. It is possible to move up and down by the space adjusting mechanism, and it is possible to change the space between the support member 112 and the pressing base 141 at the pressing position. In addition, in order to smoothly transfer the leading edge of the sheet S from the lower folding guide 111 positioned upstream of the pressing base 141 to the pressing base 141 and from the pressing base 141 to the lower folding guide 111 positioned downstream from the pressing base 141 . , the upstream edge of the pressing seat 141 and the edge of the lower folding guide 111 adjacent to the downstream side of the window have downwardly inclined portions 141a and 111a, respectively.

Next, detailed configurations of the first moving mechanism 116 and the second moving mechanism 117 in the illustrated embodiment will be described.

The support member 112 of the additional folding unit 104 is attached to a slider 124 movable along a guide rail 123 fixed to a housing 122 of the folding processing apparatus B or the like via a bracket 125 so as to be vertically movable. It moves in conjunction with the slider 124 in the horizontal direction. A rack 127 that engages with a pinion (not shown) that rotates integrally with a pulley 126 is provided on the slider 124 to drive an additional folding drive motor 128 to rotate its rotation through a belt 129 to the pulley. 126 to rotate the pulley 126 , the slider 124 can be moved horizontally along the guide rail 123 .

Further, the support member 112 is formed with a cam groove 131 that engages with a contactor 130 fixed to the housing 122 of the folding device B or the like. As the support member 112 moves horizontally, the cam groove 131 moves while being engaged with the contactor 130 , and the support member 112 moves while being guided according to the shape of the cam groove 131 . The cam groove 131 includes a first bottom horizontal portion extending substantially horizontally, a first inclined portion extending obliquely upward from the end of the first portion, and a substantially horizontal portion extending from the end of the first inclined portion. An extending top horizontal portion, a second sloping portion extending downwardly from an end of the top horizontal portion, and a second bottom horizontal portion extending generally horizontally from the end of the second sloping portion. Support is achieved by moving the support member 112 in the horizontal direction in FIG. The member 112 moves toward and away from the pressing pedestal 141, that is, vertically in FIG. Thus, the guide rail 123, the slider 124, the bracket 125, the pulley 126, the rack 127, the additional folding drive motor 128, the belt 129, the contactor 130, and the first and second inclined portions of the cam groove 131 are the first and second inclined portions. 1 moving mechanism 116 is configured. Further, by moving the support member 112 in the horizontal direction in the figure with respect to the housing 122 by the slider 124 while engaging the top horizontal portion of the cam groove 131 with the contactor 130, the support member 112 and the support member 112 are supported. A plurality of additional folding rollers 114 move along the folds of the sheet S in the horizontal direction in FIG. Thus, the guide rail 123, the slider 124, the bracket 125, the pulley 126, the rack 127, the additional folding driving motor 128, the belt 129, the contactor 130, and the top horizontal portion of the cam groove 131 constitute the second moving mechanism 117. ing. In the illustrated embodiment, the contact 130 is fixed to the housing 122 or the like and the cam groove 131 is formed in the support member 112. However, the contact 130 is fixed to the support member 112 and the cam groove 131 is formed in It goes without saying that it may be formed on the body 122 as well.

Note that when a plurality of additional folding rollers 114 are arranged at regular intervals as in the illustrated embodiment, all folds positioned between the adjacent additional folding rollers 114 are folded by the additional folding rollers. In order to press between 114 and pressing base 141, a plurality of additional folding rollers 114 must be placed on pressing base 141 at the pressing position by the distance between adjacent additional folding rollers 114 (that is, the distance of one pitch) or more. It should be moved along the crease. In the configuration of the first moving mechanism 116 described above, the slider 124 is horizontally moved while the contactor 130 and the first inclined portion of the cam groove 131 are engaged with each other to move the plurality of sliders supported by the support member 112 . The additional folding roller 114 approaches the pressing base 141 and moves to the pressing position. In addition, in the configuration of the second moving mechanism 117 described above, the slider 124 is horizontally moved while the contactor 130 and the top horizontal portion of the cam groove 131 are engaged with each other. The roller 114 moves along the crease at the pressing position. Therefore, the length of the top horizontal portion of the cam groove 131 in the horizontal direction (direction along the crease) is equal to or longer than one pitch of the adjacent additional folding rollers 114 .

Furthermore, in the illustrated embodiment, the first moving mechanism 116 includes a variable pressure adjusting cam 142 as a gap adjusting mechanism for changing the gap between the support member 112 and the pressing base 141 at the pressing position. The variable pressure adjusting cam 142 is arranged below the pressing base 141 so as to be in contact with the pressing base 141, and is rotated by a cam drive motor (not shown) around the rotation axis of the eccentric position, thereby adjusting the lower folding guide 111. The pressing pedestal 141 can be lifted toward the additional folding roller 114 through the window.

When the additional folding roller 114 is in direct contact with the fold without a sheet portion (the portion where the sheet S is divided by the fold) between the additional folding roller 114 and the fold, the control unit 140 adjusts the upper surface of the pressing pedestal 141. moves the pressing pedestal 141 to the normal position where it is at the same height as the upper surface of the lower folding guide 111. On the other hand, if the sheet portion is interposed between the additional folding roller 114 and the fold line, the pressing pedestal 141 is moved higher than the normal position. A variable pressure adjusting cam as a gap adjusting mechanism of the first moving mechanism 116 so as to move to the approach position raised toward the additional folding roller 114 to shorten the gap between the support member 112 and the pressing base 141 at the pressing position. 142 operation. As a result, at the approach position, the distance between the support member 112 supporting the additional folding roller 114 at the pressing position and the pressing base 141 is shortened. The compression amount becomes larger than the compression amount of the spring 121 at the normal position, and the pressing force applied to the sheet S between the additional folding roller 114 and the pressing base 141 becomes larger. As a result, the effect of the decrease in the pressing force applied to the fold by the sheet portion interposed between the additional folding roller 114 and the fold is offset, and the sheet portion intervenes between the additional folding roller 114 and the fold. It is possible to prevent the pressing force applied to the fold from becoming weaker than the pressing force applied by bringing the additional folding roller 114 into direct contact with the fold. Therefore, variation in the effect of additional folding due to the positional relationship between the additional folding roller 114, the fold, and the sheet portion is suppressed, and the fold with a more uniform folding height can be realized.

5-9, the operation of the additional folding unit 104 of the illustrated embodiment will now be described in detail. Here, a first fold 132 and a second fold 133 are formed by Z-folding by the folding mechanism 103 as described above. A description will be given assuming that the sheet S having three sheet portions to be folded is carried into the additional folding unit 104 .

First, the basic operation of the additional folding process for the sheet S having a plurality of folds will be described. When the sheet S from the folding mechanism 103 is received into the additionally folding unit 104 through the carry-in port 119 and the carry-in path constituted by the upper carry-in guide 118a and the lower carry-in guide 118b, FIG. Thus, the plurality of additional folding rollers 114 supported by the supporting member 112 are arranged at the receiving position, which is the home position. At this time, the lower ends of the plurality of additional folding rollers 114 supported by the support member 112 regulate the upper side of the carry-in path, and the lower folding guide 111 regulates the lower side of the carry-in path. It functions as a guide that guides the first fold line 132 to between the additional folding roller 114 and the pressing base 141 . Also, at this time, the contactor 130 is positioned at the end of the first bottom horizontal portion of the cam groove 131 . In the illustrated embodiment, a second retracted position, which will be described later, is the receiving position. However, if the additional folding roller 114 is located on the retracted position (first retracted position or second retracted position) side of the pressing position and there is a distance between the additional folding roller 114 and the pressing base 141, the receiving position is changed to the second retraction position. may be set to a position different from the retracted position of .

The position of the sheet S is detected by a sheet position detection means (not shown) provided upstream of the folding roller pair 105, and the front end side of the sheet S carried into the carry-in port 119 from the folding roller pair 105 is detected. When it is recognized that the first fold line 132 has reached below the additional folding roller 114 , the conveying of the sheet S is stopped, and the additional folding drive motor 128 is driven to rotate the pinion and rack integrally with the pulley 126 . 127 to move the support member 112 together with the slider 124 in the horizontal direction. As a result, the portion where the contactor 130 engages with the cam groove 131 moves from the first bottom horizontal portion to the first inclined portion, and the supporting member 112 moves downward toward the pressing base 141. As shown in FIG. 5B, a plurality of additional folding rollers 114 supported by the support member 112 and the pressing pedestal 141 sandwich and press the first fold line 132 of the sheet S to the pressing position. Moving. At this time, one end of the first fold line 132 of the sheet S (the upstream end in the movement direction of the additional folding rollers 114 in the forward pass) is positioned at one extreme position of the adjacent two additional folding rollers 114 . The additional pushing roller 114 disposed between and at the other extreme position is placed on the first fold 132 of the sheet S, and the other end of the first fold 132 of the sheet S (outward travel) is placed on the first fold 132 of the sheet S. downstream end in the moving direction of the additional folding roller 114 at ( ) is arranged outside the pressing member arrangement area (see FIG. 5B). In FIG. 5B, one end of the first fold line 132 of the sheet S is shown to be located at the middle position between the two adjacent additional folding rollers 114 located at the extreme positions. , "between the two adjacent additional folding rollers 114 arranged at the extreme position", the pressing point of the additional folding roller 114 arranged at the extreme position is one end of the first fold line 132 of the sheet S. Positions matching part are also included. Further, since the auxiliary member 113 to which the additional folding roller 114 is attached is biased toward the pressing pedestal 141 by the spring 121, the supporting member 112 descends, and the additional folding roller 114 is pushed through the sheet S to the pressing pedestal. After contacting 141, support member 112 can be further lowered. Along with this, the regulating member 115 also descends further to press the first crease 132 of the sheet S positioned below the additional folding roller 114, thereby reducing the thickness of the crease of the sheet S to a predetermined thickness or less. to regulate. Further, each additional folding roller 114 presses the first fold line 132 of the sheet S toward the pressing base 141 by being biased by the spring 121 . Note that the carry-in direction in this specification means the direction in which the sheet S is carried into the additional folding unit 104 from the folding roller pair 105 through the carry-in opening 119 .

When the support member 112 is further horizontally moved together with the slider 124 by driving the additional folding drive motor 128 from the state shown in FIG. The point where 130 engages cam groove 131 moves from the first sloping portion to the top horizontal portion. Then, the regulating member 115 attached to the supporting member 112 regulates the thickness of the first fold line 132 of the sheet S to a predetermined thickness (corresponding to the distance d1) or less, and the plurality of folding lines 132 supported by the supporting member 112 are regulated. At the pressing position, the additional folding roller 114 is moved relative to the pressing base 141 along the first fold line 132 of the sheet S by a distance equal to or greater than one pitch of the plurality of additional folding rollers 114 to increase the leading edge in the moving direction. The folding roller 114 moves until it passes the other end of the first fold line 132 of the sheet S (the downstream end in the moving direction of the additional folding roller 114 in the forward pass). Specifically, the other end of the first fold line 132 of the sheet S is arranged between two adjacent additional folding rollers 114 arranged at the other extreme position and additionally folded at one extreme position. When the roller 114 is placed on the first fold of the sheet S, one end of the first fold 132 of the sheet S (upstream end in the direction of movement of the additional folding roller 114 in the forward pass) is pressed. It is arranged outside the member placement area (see FIG. 5(c)). 5(c) and 7(c), the other end of the first fold line 132 of the sheet S is arranged at an intermediate position between the two adjacent additional folding rollers 114 arranged at the extreme positions. , the pressing point of the additional folding roller 114 located at the extreme position is the first position of the sheet S between the two adjacent additional folding rollers 114 located at the extreme position. A location coinciding with the other end of fold 132 is also included. In this way, the additional folding roller 114 and the pressing base 141 press the first fold line 132 over the entire area, thereby strengthening the first fold line 132, that is, performing additional folding.

When the support member 112 is further horizontally moved together with the slider 124 by driving the additional folding drive motor 128 from the state shown in FIG. portion through a second slanted portion to a second bottom horizontal portion. As a result, as shown in FIG. 5(d), the support member 112 rises together with the regulating member 115 in the direction away from the pressing pedestal 141, and the plurality of additional folding rollers 114 supported by the support member 112 presses. The first additional folding process is completed by moving to the first retraction position positioned close to and above the finished position. The first retracted position is a position different from the receiving position, which is the home position.

When the first additional folding process is completed and the state shown in FIG. 5D is reached, the sheet S can be conveyed by the conveying roller pair 102 and the folding roller pair 105 located on the upstream side in the carry-in direction. Become. The sheet S is conveyed by the conveying roller pair 102 and the folding roller pair 105 from the state shown in FIG. Then, when it is recognized that the second fold line 133 located on the rear end side in the carry-in direction of the first fold line 132 has reached below the additional folding roller 114, the sheet S is stopped to be conveyed.

When the second fold line 133 of the sheet S is stopped below the additional folding roller 114 (see FIG. 6(e)), the additional folding drive motor 128 is driven to rotate in the direction opposite to that of the outward path. The support member 112 is horizontally moved together with the slider 124 via the pinion and the rack 127 that rotate integrally with the pulley 126 in a direction opposite to that during the outward travel. As a result, the portion where the contactor 130 engages with the cam groove 131 moves from the second bottom horizontal portion to the second inclined portion, and the support member 112 is lowered toward the pressing base 141 accordingly. As shown in FIG. 6( f ), a plurality of additional folding rollers 114 supported by the support member 112 and the pressing pedestal 141 sandwich and press the second fold line 133 of the sheet S to the pressing position. Moving. At this time, the positions of the plurality of additional folding rollers 114, that is, the position of the starting point of the return pass, is the same position as the position of the end point of the forward pass. Further, at this time, one end of the second fold line 133 of the sheet S (upstream end in the movement direction of the additional folding roller 114 in the return path) is positioned at one extreme position of the adjacent two additional folding rollers. The additional folding roller 114 arranged between 114 and arranged at the other extreme position is placed on the second fold line 133 of the sheet so that the other end of the second fold line 133 of the sheet S ( The downstream end in the movement direction of the additional folding roller 114 in the return path) is arranged outside the pressing member arrangement area (see FIG. 6(f)). Further, since the auxiliary member 113 to which the additional folding roller 114 is attached is biased toward the pressing pedestal 141 by the spring 121, the supporting member 112 descends, and the additional folding roller 114 is moved through the sheet S to the pressing pedestal. After contacting 141, support member 112 can be further lowered. Along with this, the regulating member 115 is also further lowered to press the sheet portion of the sheet S positioned below the additional folding roller 114 and the second fold line 133, thereby reducing the thickness of the sheet S to a predetermined thickness or less. It regulates the thickness of the portion and the second fold 133 . Further, each additional folding roller 114 presses the sheet portion of the sheet S and the second fold line 133 toward the pressing pedestal 141 by being biased by the spring 121 .

When the support member 112 is further horizontally moved together with the slider 124 from the state shown in FIG. 6(f) by driving the additional folding drive motor 128, the state shown in FIG. 6(g) is obtained. , the point where the contactor 130 engages the cam groove 131 moves from the second inclined portion to the top horizontal portion. Then, the regulating member 115 attached to the supporting member 112 regulates the thickness of the second fold line 133 of the sheet S to a predetermined thickness (corresponding to the distance d1) or less while being supported by the supporting member 112. The plurality of additional folding rollers 114 move in the pressing position along the second fold 133 of the sheet S with respect to the pressing pedestal 141 in the direction opposite to the outward path by a distance of one pitch or more of the plurality of additional folding rollers 114 . , until the leading additional folding roller 114 in the moving direction passes over the end of the second fold line 133 of the sheet S. As shown in FIG. In this way, the additional folding roller 114 and the pressing base 141 press the entire area of the second fold line 133 to reinforce the second fold line 133, that is, perform additional folding.

From the state shown in FIG. 6G, when the additional folding drive motor 128 is driven to move the support member 112 together with the slider 124 in the horizontal direction in the opposite direction to the outward movement, the contactor 130 engages with the cam groove 131. The point to be moved moves from the top horizontal portion to the first horizontal portion via the first sloping portion. As a result, as shown in FIG. 6(h), the support member 112 rises together with the regulating member 115 in the direction away from the pressing base 141, and the plurality of additional folding rollers 114 supported by the support member 112 presses. The second additional folding process is completed by moving to a second retracted position located close to the finished position. In this embodiment, the second retracted position is set at the same position as the receiving position, which is the home position. However, it is also possible to set the second retracted position at a position different from the receiving position.

After completing a series of additional folding operations in this way, the sheet S is conveyed toward the post-processing apparatus C on the downstream side by the conveying roller pair 102 and the folding roller pair 105 located on the upstream side in the carry-in direction. The lower end portions of the plurality of additional folding rollers 114 and the bottom surface of the regulating member 115 that have been moved to the retracted position also function as guides when the additionally folded sheet S is discharged.

In the additional folding unit 104, when the additional folding roller 114 is moved from the retracted position or the receiving position to the pressing position with respect to the pressing pedestal 141 by the first moving mechanism 116, one end of the fold of the sheet S (the fold) The upstream end in the direction of movement along the fold) is arranged between two additional folding rollers 114 at one extreme position in the pressing member arrangement area, and the other end of the fold (end of movement along the fold) the downstream end in the direction) is arranged outside the pressing member arrangement area (that is, outside the additional folding roller 114 at the other extreme position in the pressing member arrangement area). On the other hand, when a plurality of additional folding rollers 114 are arranged at regular intervals in the direction in which they are moved along the folds, all the folds located between the adjacent additional folding rollers 114 are and the pressing pedestal 141, it is necessary to move the plurality of additional folding rollers 114 along the crease by at least the distance between the adjacent additional folding rollers 114 (that is, the distance of one pitch). Therefore, if the plurality of additional folding rollers 114, that is, the support member 112 is moved along the crease by a distance equal to or more than one pitch of the plurality of additional folding rollers 114, which is the minimum required for additional folding, the folds can be folded along the crease. The additional folding roller 114 at the extreme position on the upstream side in the movement direction passes over the edge of the sheet S on the upstream side in the movement direction, and is positioned adjacent to the additional folding roller 114 at the extreme position on the upstream side in the movement direction at the start of movement. The sheet S is reliably moved to the position of the additional folding roller 114, and the end portion of the sheet S positioned between the two additional folding rollers 114 at the extreme position on the upstream side in the moving direction is pressed and additionally folded at the beginning of the movement. .

In addition, in the additional folding unit 104, the movement of the plurality of additional folding rollers 114 along the fold line is performed by performing additional folding at the first fold line in the forward pass, and folding one sheet S by Z-folding, inward three-folding, or the like. When a plurality of creases are formed on the sheet, additional folding is performed on the second crease in the return trip. Therefore, the additional folding can be applied to a plurality of folds by pressing different creases in the forward and return passes, so that the increase in the time required for the additional folding can be suppressed, and the plurality of folds can be processed efficiently and in a short time. Additional folding can be performed by pressing the

In the above description, the additional folding processing by the additional folding unit 104 when the sheet S is Z-folded has been described. A sheet having three or more folds can also be handled. When only one fold line is formed on the sheet, such as when the sheet is folded in half, the fold line of the preceding sheet is additionally folded in the forward pass, the preceding sheet is discharged, and the fold line of the succeeding sheet is folded in the return pass. By additionally folding, continuous sheets can be efficiently additionally folded in a short time. Furthermore, when three or more creases are formed on the sheet, such as when the sheet is folded in four, the conveyance of the sheet is stopped each time the crease reaches below the additional folding roller 114, and the sheet is fed along the crease on the outward or return path. The additional folding can be performed by moving the plurality of additional folding rollers 114 by pressing. In addition, the object to be folded may be a sheet bundle, a single sheet, a bound sheet bundle, or an unbound sheet bundle.

Next, referring to FIGS. 7 to 9, the control of the spacing adjustment mechanism performed by the control unit 140 of the folding processing apparatus B during the additional folding process shown in FIGS. 5 and 6 will be described. Here, as shown in FIGS. 8 and 9, it is folded in a Z-shape so that the first fold line 132 is positioned above the sheet portion and the second fold line 133 is positioned below the sheet portion. It is assumed that the folded sheet S is carried into the additional folding unit 104 .

In the folding device B, the folding mechanism 103 first folds the sheet S so that the first fold line 132 is positioned above the sheet portion and the second fold line 133 is positioned below the sheet portion. A sheet S is folded into a Z shape (step S1). Specifically, upon recognizing that the leading edge of the sheet S has been nipped by the pair of folding rollers 105, the control unit 140 controls the folding mechanism 103 to horizontally move the veneer 107 to form a folded portion. A space for forming a loop is formed between the lower transport guide 109 and the lower folding guide 111 by moving it to the retracted position below the lower transport guide 109 . After the space for forming the loop is formed, when the sheet S is conveyed by a predetermined amount in a state where the leading edge of the sheet S is nipped by the pair of folding rollers 105, the intermediate portion of the sheet S is bent downward in the space for forming the loop. Then create the loop part. In this state, the thrust plate 107 is horizontally moved from the retracted position toward the folding roller pair 105 to form a folded portion. By driving and conveying the sheet S, the first fold line 132 is formed, and after the thrust plate 107 is moved to the retracted position, the sheet S is conveyed by the folding roller pair 105 to nip the loop portion. , a second fold line 133 is formed, and the Z-folded sheet S is conveyed downstream.

The sheet S that has been folded by the folding mechanism 103 is conveyed into the additional folding unit 104 through the inlet 119 by the pair of folding rollers 105 (step S2). In the additional folding unit 104, the sheet S is placed in the additional folding unit 104 in a state in which the plurality of additional folding rollers 114 are arranged at the retracted position or the receiving position spaced apart from the pressing position to the retracted position with respect to the pressing pedestal 141. accept. At this time, the control unit 140 controls the position of the sheet S as shown in FIG. , the sheet S is stopped when it is recognized that the first fold line 132 of the sheet S has reached the additional folding portion, that is, below the additional folding roller 114 (step S3).

When the first fold line 132 stops at the additional folding portion, the control unit 140 controls the operation of the interval adjustment mechanism included in the first moving mechanism 116 to determine whether or not the additional folding roller 114 can directly contact the fold line. In other words, depending on whether or not a sheet portion is interposed between the additional folding roller 114 and the fold line, the interval at the pressing position between the support member 112 supporting the additional folding roller 114 and the pressing base 141 is changed (step S4). . When the fold is positioned above the sheet portion and the additional folding roller 114 directly contacts the fold, such as the first fold 132 on the leading side of the sheet S in the conveying direction, the control unit 140 controls the additional folding rollers 114 By controlling the operations of the first moving mechanism 116 and the gap adjusting mechanism, the support member 141 is moved to the pressing member 141 so that the gap at the pressing position between the supporting member 112 and the pressing pedestal 141 becomes the first spacing X1. 112 is moved, the second moving mechanism 117 moves the additional folding roller 114 along the crease with respect to the pressing base 141 at the pressing position (step S5).

In the illustrated embodiment, the control unit 140 drives a cam drive motor (not shown) so that the upper surface of the pressing base 141 is aligned with the lower folding guide 111, as shown in FIG. 8(b). Rotate the variable pressure adjusting cam 142 in contact with the pressing base 141 so that it becomes the same height as the upper surface, and at the same time, the first moving mechanism 116 moves the support member 112 to the height position at the pressing position by a predetermined distance to the pressing base. Lower towards 141. After that, the second moving mechanism 117 moves the plurality of additional folding rollers 114 supported by the support member 112 along the first folding line 132 with respect to the pressing base 141, and the first folding roller 114 is folded with the first pressing force. The first fold line 132 is pressed, and additional folding processing is performed on the first fold line 132 .

When the additional folding process for the first fold line 132 is completed, the control unit 140 is supported by the support member 112 in the direction away from the pressing base 141 by the first moving mechanism 116, as shown in FIG. 8(c). After the plurality of additional folding rollers 114 are moved (raised) toward the retracted position by a predetermined distance, the sheet S is conveyed downstream (step S6).

The sheet S subjected to the additional folding process for the first fold line 132 is conveyed, and sheet position detection means (not shown) provided upstream of the folding roller pair 105 is used as in the case of the first fold line 132 . ), the controller 140 recognizes that the second fold line 133 has reached the additionally folded portion based on the position of the sheet S detected by ), the control unit 140 changes the position of the sheet S as shown in FIG. When the second fold line 133 reaches the additional folding portion, that is, below the additional folding roller 114, the sheet S is stopped (step S3).

When the second fold 133 stops at the additional folding portion, the control unit 140 controls the operation of the interval adjustment mechanism included in the first moving mechanism 116 to perform additional folding, as in the case of the first fold 132 . Depending on whether or not the sheet portion is interposed between the roller 114 and the fold line, the interval at the pressing position between the support member 112 supporting the additional folding roller 114 and the pressing base 141 is changed (step S4). When the fold line is located below the sheet portion and the sheet portion is interposed between the additional folding roller 114 and the fold line, such as the second fold line 133 on the trailing end side of the sheet S in the conveying direction, the control unit 140 A first moving mechanism 116 and an interval adjusting mechanism are provided so that the interval between the support member 112 supporting the plurality of additional folding rollers 114 and the pressing base 141 at the pressing position becomes a second interval X2 shorter than the first interval X1. After the support member 112 is moved with respect to the pressing base 141 by controlling the operation of , the additional folding roller 114 is moved along the crease with respect to the pressing base 141 at the pressing position by the second moving mechanism 117 (step S8). In the illustrated embodiment, the control unit 140 drives a cam drive motor (not shown) so that the upper surface of the pressing base 141 is aligned with the lower folding guide 111, as shown in FIG. 9(e). The voltage change adjustment cam 142 in contact with the pressing base 141 is rotated to raise the pressing base 141 to a position higher than the upper surface, and the first moving mechanism 116 moves the pressure base 141 to a predetermined height position at the pressing position. After the supporting member 112 is lowered toward the pressing base 141 by a distance, the second moving mechanism 117 moves the plurality of additional folding rollers supported by the supporting member 112 along the second folding lines 133 with respect to the pressing base 141 . 114 is moved to press the second fold line 133 with a second pressing force, and the second fold line 133 is additionally folded.

At this time, the support member 112 is arranged at a position separated from the pressing base 141 by a second distance X2 shorter than the first distance X1 at the pressing position, and in the case of pressing the first fold line 132, , the amount of compression of the spring 121 interposed between the auxiliary member 113 to which the additional folding roller 114 is attached and the support member 112 that supports the auxiliary member 113 is increased. The second pressing force applied is greater than the first pressing force applied to the first fold line 132 . When the sheet portion intervenes between the additional folding rollers 114, the force is dispersed and the pressing force acting on the fold is reduced. The reduction in pressure can be offset, and it is possible to prevent the pressing force from becoming weaker than the pressing force that is applied by bringing the additional folding roller 114 into direct contact with the fold line. Therefore, variation in the effect of additional folding due to the positional relationship between the additional folding roller 114, the fold, and the sheet portion is suppressed, and the fold with a more uniform folding height can be realized.

Further, the control unit 140 interposes the sheet portion between the plurality of additional folding rollers 114 and the folds to fold the plurality of additional folding rollers 114 and the pressing pedestals, like the additional folding processing for the second fold line 133 in step S8. 141 (that is, the distance between the support member 112 that supports the plurality of additional folding rollers 114 at the pressing position and the pressing base 141 is set to a second distance shorter than the first distance X1). When the additional folding roller 114 is moved along the fold while the support member 112 is moved with respect to the pressing pedestal 141 so as to be X2), the additional folding processing for the first fold 132 in step S4 is performed. It is preferable to control the second moving mechanism 117 so as to move the plurality of additional folding rollers 114 along the folds at a speed lower than the speed when the additional folding rollers 114 are brought into direct contact with the folds and pressed. . As a result, the amount of work applied to the crease between the additional folding roller 114 and the pressing pedestal 141 is increased, so that the effect of strengthening the crease can be enhanced. Therefore, it is possible to further suppress variations in the additional folding effect due to the positional relationship between the additional folding roller 114, the fold line, and the sheet portion, thereby realizing a fold line with a more uniform folding height.

Furthermore, the control unit 140 acquires information about the basis weight of the sheets S to be additionally folded from the sheet basis weight recognition means, controls the operation of the interval adjustment mechanism according to the basis weight of the sheets S, and You may make it change the 2nd space|interval X2 of the support member 112 and the press base 141. FIG. For example, in step S8, if the basis weight of the sheet S acquired by the sheet basis weight recognizing means is lower than a predetermined value, the control unit 140 controls the rotational position of the variable pressure adjustment cam 142, which is the interval adjustment mechanism. Then, the second distance X2 between the support member 112 and the pressing base 141 at the pressing position is increased ( However, it is smaller than the first interval X1), and the pressing force applied to the fold between the additional folding roller 114 and the pressing pedestal 141 may be weakened. When a sheet portion is interposed between the additional folding roller 114 and the fold line like the second fold line 133 subjected to the additional folding process in step S8, a step is formed under the sheet portion due to the existence of the fold line. When the basis weight of the sheet S is small, the pressing force of the additional folding roller 114 tends to leave traces of steps on the sheet portion. As described above, in step S8, if the pressing force is weakened when the basis weight of the sheet S is smaller than a predetermined value, the sheet portion is interposed between the additional folding roller 114 and the fold line. , it is possible to prevent the deterioration of the quality of the additionally folded sheet S due to the trace of the step remaining on the sheet portion. A method for acquiring information about the basis weight of the sheet S is not particularly limited. A sheet grammage detection sensor provided in the conveying path 101 or the like may also be used.

When the additional folding process for the second fold line 133 is completed, similarly to the case of the additional folding process for the first fold line 132, the control unit 140 moves the first moving mechanism 116 as shown in FIG. 9(f). After the plurality of additional folding rollers 114 supported by the support member 112 are raised by a predetermined distance toward the retracted position in the direction away from the pressing base 141, the sheet S is conveyed downstream (step S6). .

When there are two or more creases such as Z-folding or tri-folding, the operations from step S3 to step S6 are repeated until the additional folding processing for the last crease is completed (step S7). is arranged in the additional folding portion, and a plurality of additional folding rollers 114 are moved along the folds of the sheet S to perform additional folding. When the additionally folding process is completed for all folds, the additionally folded sheet S is conveyed to the post-processing apparatus C. As shown in FIG.

Although the sheet pressing device of the present invention and the image forming system including the same have been described above with reference to the illustrated embodiments, the present invention is not limited to the illustrated embodiments. For example, in the illustrated embodiment, a spring 121 is provided between an auxiliary member 113 to which each additional folding roller 114 is rotatably attached and a support member 112 that movably supports the additional folding roller. 114 is biased toward the pressing pedestal 141, but as shown in FIG. A spring 144 may be provided between 143 and the pressing base 141 to bias the pressing base 141 toward the additional folding roller 114 . In the illustrated embodiment, the first moving mechanism 116 includes guide rails 123, sliders 124, brackets 125, pulleys 126, racks 127, additional folding drive motors 128, belts 129, contacts 130, and cam grooves 131. The second moving mechanism 117 includes a guide rail 123, a slider 124, a bracket 125, a pulley 126, a rack 127, an additional folding drive motor 128, a belt 129, and a contact. If the support member 112 can be moved toward and away from the pressing base 141 and the support member 112 can be moved along the fold of the sheet S, the first The configurations of the moving mechanism 116 and the second moving mechanism 117 are not limited. For example, as shown in FIG. 11, a guide rail 123 and a slider 124 are provided on a base member 145, the slider 124 and the support member 112 are connected by a bracket 125, and the slider 124 is driven by a linear motion mechanism (not shown). By doing so, the support member 112 can be horizontally moved with respect to the base member 145, and the base member 145 can be moved up and down by the lifting mechanism 146, thereby making it possible to move the support member 112 up and down. In this case, the guide rail 123, the slider 124, the bracket 125, and the linear motion mechanism function as the second movement mechanism, and the lift mechanism 146 functions as the first movement mechanism. Further, in this case, the lifting mechanism 146 can also serve as a gap adjusting mechanism.

A Image forming apparatus B Folding device C Post-processing device 104 Additional folding unit 110 Upper folding guide 111 Lower folding guide 112 Supporting member 113 Auxiliary member 114 Additional folding roller 115 Regulating member 116 First moving mechanism 117 Second moving mechanism 118 carry-in guide 118a upper carry-in guide 118b lower carry-in guide 119 carry-in port 121 spring 140 control unit 141 pressing pedestal 142 transformer adjustment cam 143 base 144 spring 145 base member 146 lifting mechanism

Claims (11)

Additional folding of the Z-shaped folded sheet by a first fold and a second fold formed between the first edge and the second edge on the opposite side of the first edge A sheet pressing device for applying
a first portion between the first fold and the second fold; a second portion between the first fold and the first edge; and a second portion between the second edge and the second edge. The folded sheet divided into the third part between the folds is placed on the second part facing the first surface of the first part and the second part on the side opposite to the first surface of the first part. a conveying means that conveys the second portion so that the second portion overlaps the second fold line in a state in which the third portion faces the surface;
a pressing roller that rotates around a rotation axis extending in the transport direction of the transport means and presses the folded sheets;
a facing member arranged to face the pressing roller;
A first position that presses the folded sheet located between the pressing roller and the opposing member, and a second position that moves away from the opposing member in the thickness direction of the sheet pressed at the first position. a first moving mechanism capable of moving the pressing roller to a position between the pressing roller and the opposing member and adjusting a pressing force against the sheet pressed between the pressing roller and the opposing member;
In a state in which the pressing roller is moved to the first position with respect to the facing member by the first moving mechanism, the pressing roller is conveyed so as to press the first fold line or the second fold line. a second moving mechanism for moving along a direction intersecting the direction;
with
the conveying means conveys the folded sheet such that the second portion of the folded sheet faces the pressing roller and the third portion faces the opposing member;
When the second fold is positioned between the pressing roller and the opposing member, the pressing force applied to the folded sheet between the pressing roller and the opposing member is such that the first fold is the stronger than the pressing force applied to the folded sheet between the pressing roller and the opposing member when positioned between the pressing roller and the opposing member;
A sheet pressing device characterized by: The first moving mechanism includes a support member that rotatably supports the pressing roller and a spacing adjustment mechanism that adjusts the spacing between the opposing member,
The space adjusting mechanism adjusts the distance between the supporting member and the opposing member when the second fold is positioned between the pressing roller and the opposing member, and the distance between the pressing roller and the opposing member is adjusted between the first fold and the pressing roller. 2. The sheet pressing device according to claim 1, wherein the distance between said support member and said opposing member is shorter than the distance between said supporting member and said opposing member. The interval adjusting mechanism further includes an eccentric cam that contacts a surface of the opposing member that is opposite to the sheet contact surface that contacts the folded sheet,
adjusting the spacing between the support member and the opposing member by rotating the eccentric cam;
3. The sheet pressing device according to claim 2, wherein: The first moving mechanism includes a biasing section that biases the opposing member toward the pressing roller, and a base that supports the biasing section,
The first moving mechanism adjusts the distance between the support member and the base portion when the second fold is positioned between the support member and the opposing member, and the first fold and the pressing roller are configured to move the distance between the support member and the base. 3. The sheet pressing device according to claim 2 , wherein the distance between the supporting member and the base portion is shorter than the distance between the supporting member and the base when positioned between the opposing members. The second moving mechanism adjusts the speed at which the pressing roller moves in the intersecting direction when the second fold is positioned between the pressing roller and the opposing member. 5. The method according to any one of claims 1 to 4, characterized in that, when positioned between the pressing roller and the opposing member , the pressing roller moves at a speed lower than the speed at which the pressing roller moves in the intersecting direction. sheet pressing device. further comprising acquisition means for acquiring information about the basis weight of the folded sheet;
The first moving mechanism moves the second crease between the pressing roller and the opposing member when the basis weight of the folded sheet acquired by the acquiring means is equal to or greater than a predetermined basis weight value. When the basis weight of the folded sheet obtained by the obtaining means is smaller than the predetermined basis weight than the pressing force applied to the folded sheet when the pressing roller and the facing member are positioned weakening the pressing force applied to the folded sheet when the second fold is located between
The sheet pressing device according to any one of claims 1 to 5, characterized in that: Additional folding of the Z-shaped folded sheet by a first fold and a second fold formed between the first edge and the second edge on the opposite side of the first edge A sheet pressing device for applying
a first portion between the first fold and the second fold; a second portion between the first fold and the first edge; and a second portion between the second edge and the second edge. The folded sheet divided into the third part between the folds is placed on the second part facing the first surface of the first part and the second part on the side opposite to the first surface of the first part. a conveying means that conveys the second portion so that the second portion overlaps the second fold line in a state in which the third portion faces the surface;
a pressing member that presses the folded sheet;
a support member that rotatably supports the pressing member;
a facing member arranged to face the pressing member;
a spacing adjustment mechanism that adjusts the spacing between the supporting member and the facing member;
with
the conveying means conveys the folded sheet such that the second portion of the folded sheet faces the pressing member and the third portion faces the opposing member;
The gap adjusting mechanism is configured such that the second fold is closer to the pressing member than the gap between the supporting member and the opposing member when the first fold is positioned between the pressing member and the opposing member. narrowing the distance between the supporting member and the opposing member when positioned between the opposing member;
A sheet pressing device characterized by: 8. The sheet pressing device according to claim 1, wherein the second portion of the folded sheet has a larger area than the first portion. The conveying means is a pair of folding rollers for forming the first fold and the second fold on the sheet,
generating the folded sheet by nipping and conveying the sheet by the pair of folding rollers;
The sheet pressing device according to any one of claims 1 to 8, characterized in that: a pair of conveying rollers provided upstream of the pair of folding rollers in the conveying direction for nipping and conveying a sheet;
A first position permitting the formation of a hanging loop in the sheet by the pair of conveying rollers continuing to convey the sheet in a state where the pair of folding rollers nips the sheet and stops rotating, and the loop is formed. a projecting member movable to a second position for projecting a portion of the sheet toward the nip portion of the pair of folding rollers;
10. The sheet pressing device according to claim 9, comprising: an image forming apparatus that forms an image on a sheet;
11. The sheet pressing device according to claim 9 or 10, wherein the sheet conveyed from the image forming apparatus is folded.
An image forming system comprising:

Images