Sheet processing device

Abstract

To provide a sheet processing device capable of suppressing a decrease in processing quality.SOLUTION: The sheet conveying path between the folding unit and the fold-reinforcing unit includes an upper guide and a lower guide. The upper guide is disposed above the conveying reference surface and guides the conveyance of a sheet along an upper guide line which is an intersection line with the evaluation surface. The lower guide is disposed below the conveying reference surface and guides the conveyance of the sheet along a lower guide line which is an intersection line with the evaluation surface. The intersection point between the orthogonal line passing through a first position and the lower guide line is defined as a first intersection point. The intersection point between the orthogonal line passing through a second position on the downstream side from the first position and the lower guide line is defined as a second intersection point. The intersection point between the orthogonal line passing through the first position and the upper guide line is defined as a third intersection point. The first distance between the first position and the first intersection point is greater than the second distance between the second position and the second intersection point. The first distance is greater than the third distance between the first position and the third intersection point.SELECTED DRAWING: Figure 4

Description

[Technical field]

[0001] An embodiment of the present invention relates to a sheet processing apparatus. [Background technology]

[0002] A sheet processing apparatus having a folding unit and a fold-reinforcing unit is in use. The folding unit folds a sheet to form a crease. The fold-reinforcing unit reinforces the crease formed by the folding unit. There is a demand for a sheet processing apparatus that can suppress a decrease in processing quality. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2003-261258 A Summary of the Invention [Problem to be solved by the invention]

[0004] An object of the present invention is to provide a sheet processing apparatus capable of suppressing a decrease in processing quality. [Means for solving the problem]

[0005] The sheet processing device of the embodiment has a folding unit, a fold reinforcing unit, an upper guide, and a lower guide. The folding unit folds a sheet to form a crease. The fold reinforcing unit folds the crease of the sheet formed by the folding unit. In the sheet conveying path between the folding unit and the fold reinforcing unit, a conveying reference plane, an orthogonal plane, an evaluation plane, a conveying reference line, an orthogonal line, and a second position are defined as follows. The conveying reference plane is a plane along which the center of the sheet in the thickness direction is conveyed. The orthogonal plane is a plane perpendicular to the conveying direction of the sheet. The evaluation plane is a plane parallel to the conveying direction and perpendicular to the conveying reference plane. The conveying reference line is an intersection line between the conveying reference plane and the evaluation plane. The orthogonal line is an intersection line between the orthogonal plane and the evaluation plane. The second position is a position downstream of the conveying reference line in the conveying direction from the first position. The upper guide is disposed above the conveying reference plane, and guides the conveying of the sheet along the upper guide line which is an intersection line with the evaluation plane. The lower guide is disposed below the transport reference surface and guides transport of the sheet along a lower guide line which is an intersection line with the evaluation surface. The intersection point between the orthogonal line passing through the first position and the lower guide line is defined as a first intersection point. The intersection point between the orthogonal line passing through the second position and the lower guide line is defined as a second intersection point. The intersection point between the orthogonal line passing through the first position and the upper guide line is defined as a third intersection point. The first distance between the first position and the first intersection point is greater than the second distance between the second position and the second intersection point. The first distance is greater than the third distance between the first position and the third intersection point. [Brief description of the drawings]

[0006] [Figure 1] FIG. 1 is a schematic diagram of an image forming apparatus. [Diagram 2] FIG. 4 is a front view of a saddle folding mechanism of the sheet processing apparatus. [Diagram 3] FIG. 2 is a front cross-sectional view of the periphery of a conveying path in the sheet processing apparatus according to the embodiment. [Figure 4] FIG. [Diagram 5] FIG. 11 is a schematic configuration diagram of the periphery of a transport path in a first modified example of the embodiment. [Figure 6] FIG. 11 is a schematic configuration diagram of the periphery of a transport path in a second modified example of the embodiment. [Figure 7] FIG. [Figure 8] FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0007] Hereinafter, a sheet processing apparatus according to an embodiment will be described with reference to the drawings. 1 is a schematic configuration diagram of an image forming apparatus 1. For example, the image forming apparatus 1 is placed in a workplace. The image forming apparatus 1 has an image forming apparatus main body 100 and a sheet processing apparatus 200. The image forming apparatus main body 100 and the sheet processing apparatus 200 are placed adjacent to each other.

[0008] The image forming apparatus main body 100 will now be described. The image forming apparatus main body 100 forms an image on a sheet (recording medium) using a recording agent. For example, the sheet is plain paper or label paper. A specific example of the recording agent is toner. The toner is either a toner used as a decolorizable recording agent or a toner used as a non-decolorizable recording agent.

[0009] For example, the image forming apparatus main body 100 is a multifunction machine. As shown in Fig. 1, the image forming apparatus main body 100 has a display unit 15, an operation unit 14, an image reading unit 16, a printer unit 17, a sheet storage unit 18, a paper discharge roller 19, and a first control unit 90.

[0010] The display unit 15 is an image display device such as a liquid crystal display, an organic EL (Electro Luminescence) display, etc. The display unit 15 displays various information related to the image forming apparatus main body 100 and the sheet processing apparatus 200. The operation unit 14 has a plurality of buttons. The operation unit 14 accepts operations by the user. The operation unit 14 outputs a signal corresponding to the operation performed by the user to the first control unit 90 of the image forming apparatus main body 100. The display unit 15 and the operation unit 14 may be configured as an integrated touch panel.

[0011] The image reading unit 16 reads the image information of the object to be read as light and dark, and outputs the read image information to the printer unit 17. The sheet storage unit 18 stores sheets to be used for image formation. The sheet storage unit 18 supplies the stored sheets to the printer unit 17.

[0012] Printer unit 17 forms an image on a sheet based on image information generated by image reading unit 16 or image information received via a communication path. Printer unit 17 has an image forming unit, a transfer unit, and a fixing device. The image forming unit forms an electrostatic latent image on a photoconductor drum based on the image information. The image forming unit forms a visible image by attaching toner to the electrostatic latent image. The transfer unit transfers the visible image onto the sheet. The fixing device heats and pressurizes the toner to fix the visible image onto the sheet. The paper discharge rollers 19 are disposed near the paper discharge port of the image forming apparatus main body 100. The paper discharge rollers 19 send out the sheet on which the image has been formed to the sheet processing apparatus 200. The first control unit 90 controls the operations of the image forming apparatus main body 100 and each unit of the sheet processing apparatus 200 .

[0013] The sheet processing apparatus 200 will be described. The sheet processing apparatus 200 performs post-processing on the sheet P on which an image has been formed. For example, the post-processing is stapling or saddle folding. The sheet processing apparatus 200 includes a second control unit 95, a stapling mechanism 20, and a saddle folding mechanism 30. The second control unit 95 controls the operations of the individual units of the sheet processing apparatus 200 .

[0014] The staple mechanism 20 includes a waiting tray 21, a processing tray 22, and a stapler 23. The stapler 23 staples the peripheral edges of a plurality of sheets P. The stapled sheets P are transported by a transport belt 24 and discharged onto a movable tray 27.

[0015] The sheet processing apparatus 200 has a movable tray 27 and an upper tray 26. Stapled sheets P are discharged to the movable tray 27. Non-stapled sheets P are discharged to the upper tray 26.

[0016] 2 is a front view of the saddle folding mechanism 30 of the sheet processing apparatus 200. The saddle folding mechanism 30 has a sheet support section 31, a processing section 33, and a lower tray 28 (see FIG. 1). The processing section 33 has a staple section 34, a folding unit 35, and a fold-reinforcing unit 40.

[0017] The sheet support section 31 supports the sheet P. The sheet support section 31 has a saddle folding tray 32, a lifting device 38, and an alignment member 39. The saddle folding tray 32 is capable of placing the sheet P on a first surface S thereof.

[0018] As a local coordinate system of the saddle folding mechanism 30, the X direction, Y direction, and Z direction of the Cartesian coordinate system are defined as follows. The X direction is a normal direction of the first surface S of the saddle folding tray 32. The +X direction is a direction in which the sheet P is placed on the saddle folding tray 32. The Y direction is a direction in which an intersection line between the first surface S and the horizontal plane extends. The Z direction (second direction) is a direction parallel to the first surface S and perpendicular to the Y direction. The +Z direction is a direction from the folding unit 35 toward the staple section 34.

[0019] The saddle folding tray 32 is substantially plate-shaped, and is capable of placing the sheet P on a first surface S in the +X direction. The saddle folding trays 32 are disposed on both sides of the folding unit 35 in the Z direction. The lifting device 38 supports the lower end of the sheet P placed on the saddle folding tray 32. The lifting device 38 moves up and down in the Z direction to move the sheet P to the processing section 33. The alignment member 39 aligns the position of the sheet P placed on the saddle folding tray 32 in the Y direction (lateral alignment).

[0020] The staple section 34 is located in the +Z direction of the folding unit 35. The staple section 34 performs stapling processing at a predetermined position of the sheet P. For example, the predetermined position of the sheet P is the center of the sheet P in the Z direction.

[0021] The folding unit 35 is located in the center of the saddle folding mechanism 30. The folding unit 35 folds the center of the sheet P in the Z direction to form a crease in the sheet P. The folding unit 35 has a blade 36 and a pair of folding rollers 37.

[0022] The blade 36 is flat and parallel to the XY plane. The blade 36 is tapered in the +X direction. The blade 36 can move in the X direction passing through the saddle folding tray 32. The blade 36 can come into contact with the center of the sheet P in the Z direction. The pair of folding rollers 37 are located in the +X direction of the saddle folding tray 32. The pair of folding rollers 37 are aligned in the Z direction. The pair of folding rollers 37 are long in the Y direction. The rotation axes of the pair of folding rollers 37 are parallel to the Y direction.

[0023] The fold reinforcing unit 40 is located in the +X direction of the pair of folding rollers 37, with a conveyance path 50 of the sheet P interposed therebetween. The fold reinforcing unit 40 reinforcing the crease of the sheet P. 3 is a front cross-sectional view of the periphery of the conveying path 50 in the sheet processing apparatus 200 of the embodiment. The fold reinforcing unit 40 has a frame 41, a pair of support plates 44, 45, and a pair of fold reinforcing rollers 46, 47.

[0024] The frame 41 supports components of the fold-reinforcing unit 40. A slit 42 extending in the Y direction is formed on the -X direction side of the frame 41. The slit 42 allows the sheet P that has been saddle-folded by the folding unit 35 to enter.

[0025] The pair of support plates 44, 45 includes a first support plate 44 and a second support plate 45. The first support plate 44 extends in the +X direction from the -Z direction end of the slit 42. The first support plate 44 is fixed to the frame 41. The first support plate 44 supports the saddle-folded sheet P from the -Z direction. The second support plate 45 is located in the +Z direction of the first support plate 44. The second support plate 45 is movable in the Z direction. The second support plate 45 presses the saddle-folded sheet P from the +Z direction.

[0026] The pair of fold reinforcing rollers 46, 47 are in the +X direction of the pair of support plates 44, 45. The pair of fold reinforcing rollers 46, 47 are aligned in the Z direction. The rotation axes of the pair of fold reinforcing rollers 46, 47 are parallel to the X direction. The pair of fold reinforcing rollers 46, 47 can move in the Y direction synchronously. The pair of fold reinforcing rollers 46, 47 includes a first roller 46 and a second roller 47. The end of the +Z direction on the outer peripheral surface of the first roller 46 is at approximately the same position in the Z direction as the surface of the +Z direction of the first support plate 44. The end of the -Z direction on the outer peripheral surface of the second roller 47 is at approximately the same position in the Z direction as the surface of the -Z direction of the second support plate 45. The second support plate 45 and the second roller 47 can move in the Z direction synchronously.

[0027] 1, the lower tray 28 is located in the +X direction of the fold-reinforcing unit 40 and at the bottom of the sheet processing apparatus 200. The saddle-folded sheet P is discharged to the lower tray 28.

[0028] For example, the saddle folding mechanism 30 shown in FIG. 2 performs a bookbinding process in which multiple sheets P are saddle-folded to form a booklet. The lifting device 38 lifts and lowers in the Z direction while supporting the sheets P. The lifting device 38 positions the center of the sheets P in the Z direction at the position of the staple section 34. The staple section 34 staples the multiple sheets P. The lifting device 38 moves the multiple sheets P in the -Z direction. The lifting device 38 positions the center of the sheets P in the Z direction at the position of the folding unit 35. The blade 36 moves in the +X direction to push the sheets P between a pair of folding rollers 37. The multiple sheets P are saddle-folded at the center in the Z direction, and creases are formed in the multiple sheets P.

[0029] The saddle-folded sheet P is conveyed in the +X direction. The sheet P enters the slit 42 of the fold reinforcing unit 40 shown in FIG. 3. When the crease at the leading edge of the sheet P reaches the position of the pair of fold reinforcing rollers 46, 47, the conveyance of the sheet P is stopped. The second support plate 45 and the second roller 47 move in the -Z direction in synchronization. The sheet P is sandwiched between the pair of support plates 44, 45, and the crease of the sheet P is sandwiched between the pair of fold reinforcing rollers 46, 47. The pair of fold reinforcing rollers 46, 47 move in the Y direction in synchronization. The pair of fold reinforcing rollers 46, 47 pinch the crease of the sheet P and rotate and move along the Y direction in which the crease extends. This causes the creases of the multiple sheets P to be folded and reinforcing. This completes the bookbinding process of the multiple sheets P. The bound multiple sheets P are discharged to the lower tray 28 shown in FIG. 1.

[0030] As shown in FIG. 3, a conveying path 50 for the saddle-folded sheet P is formed between the pair of folding rollers 37 of the folding unit 35 and the re-folding unit 40. 4 is a schematic diagram of the periphery of the transport path 50. An upper guide U and a lower guide L are disposed on the transport path 50. The upper guide U and the lower guide L are formed in a flat plate shape from a metal material such as aluminum or a resin material.

[0031] The conveying direction of the sheet P in the conveying path 50 is the X direction. In the conveying path 50, a conveying reference plane SS, an orthogonal plane VS, an evaluation plane ES, a conveying reference line SL, and an orthogonal line VL are defined as follows. The conveying reference plane SS is a plane along which the center of the saddle-folded sheet P in the thickness direction is conveyed. The conveying reference plane SS is a plane that is the movement trajectory of the ridge of the blade 36 of the folding unit 35 (see FIG. 2). The orthogonal plane VS is a plane perpendicular to the X direction (the conveying direction of the sheet P). The evaluation plane ES is a plane parallel to the X direction and perpendicular to the conveying reference plane SS. The paper surface of FIG. 4 corresponds to the evaluation plane ES. The conveying reference line SL is the intersection line between the conveying reference plane SS and the evaluation plane ES. The orthogonal line VL is the intersection line between the orthogonal plane VS and the evaluation plane ES.

[0032] The lower guide L is positioned in the -Z direction (below) of the transport reference surface SS. The +Z direction surface of the lower guide L is the lower guide surface LS. The lower guide surface LS is a flat surface. The lower guide L guides the transport of the sheet P along the flat lower guide surface LS. The intersection line between the lower guide L and the evaluation surface ES is the lower guide line LL. The lower guide line LL is a straight line. The lower guide L guides the transport of the sheet P along the straight lower guide line LL.

[0033] The upper guide U is positioned in the +Z direction (above) of the transport reference surface SS. The -Z direction surface of the upper guide U is the upper guide surface US. The upper guide surface US is a flat surface. The upper guide U guides the transport of the sheet P along the flat upper guide surface US. The intersection line between the upper guide U and the evaluation surface ES is the upper guide line UL. The upper guide line UL is a straight line. The upper guide U guides the transport of the sheet P along the upper guide line UL, which is a straight line.

[0034] In the transport path 50, a first position Pa and a second position Pb are defined as follows. The first position Pa is an arbitrary position on the transport reference line SL. The second position Pb is a position on the transport reference line SL in the +X direction (downstream in the transport direction of the sheet P) from the first position Pa.

[0035] The intersection point between the orthogonal line VL passing through the first position Pa and the lower guide line LL is the first intersection point Ca. The intersection point between the orthogonal line VL passing through the second position Pb and the lower guide line LL is the second intersection point Cb. The intersection point between the orthogonal line VL passing through the first position Pa and the upper guide line UL is the third intersection point Cc. The intersection point between the orthogonal line VL passing through the second position Pb and the upper guide line UL is the fourth intersection point Cd.

[0036] The distance between the first position Pa and the first intersection point Ca is the first distance Da. The distance between the second position Pb and the second intersection point Cb is a second distance Db. The distance between the first position Pa and the third intersection point Cc is a third distance Dc. The distance between the second position Pb and the fourth intersection point Cd is a fourth distance Dd.

[0037] The first distance Da is greater than the second distance Db. That is, the lower guide L is inclined so as to move away from the transport reference surface SS in the -X direction. The lower guide L is inclined so as to move closer to the transport reference surface SS in the +X direction. The +X direction end of the lower guide L is at approximately the same position in the Z direction as the +Z direction surface of the first support plate 44. The +X direction end of the lower guide L is connected to the first support plate 44 via the lower connecting plate LX.

[0038] The third distance Dc is greater than the fourth distance Dd. That is, the upper guide U is inclined so as to move away from the transport reference surface SS in the -X direction. The upper guide U is inclined so as to move closer to the transport reference surface SS in the +X direction. The +X direction end of the upper guide U is at approximately the same position in the Z direction as the +Z direction end of the slit 42. The +X direction end of the upper guide U is connected to the frame 41 via an upper connecting plate UX. The third distance Dc and the fourth distance Dd may be equal to each other. That is, the upper guide U may be substantially parallel to the transport reference surface SS.

[0039] The lower connecting plate LX and the upper connecting plate UX are parallel to the conveying reference plane SS. The distance in the Z direction between the lower connecting plate LX and the upper connecting plate UX is equal to or greater than the thickness of the maximum booklet that can be formed by saddle-folding the sheet P. In other words, the distance in the Z direction between the lower connecting plate LX and the upper connecting plate UX is equal to or greater than twice the thickness of the sheet P before saddle-folding in the maximum booklet that can be formed.

[0040] The first distance Da is greater than the third distance Dc. The second distance Db is greater than the fourth distance Dd. That is, the lower guide L is farther away from the transport reference surface SS than the upper guide U. The angle LA between the lower guide surface LS and the transport reference surface SS is greater than the angle UA between the upper guide surface US and the transport reference surface SS. The angle LA between the lower guide line LL and the transport reference line SL is greater than the angle UA between the upper guide line UL and the transport reference line SL.

[0041] FIG. 8 is an explanatory diagram of the operation of the comparative example. The lower guide L and the upper guide U of the comparative example are parallel to the transport reference surface SS. The sheet P saddle-folded by the folding unit 35 enters the transport path 50 from the pair of folding rollers 37. The sheet P enters between the lower guide L and the upper guide U of the transport path 50. The saddle-folded sheet P tries to open in a direction away from the transport reference surface SS due to the restoring force of the fold. However, the lower guide L and the upper guide U of the comparative example are parallel to the transport reference surface SS and have a narrow gap in the Z direction. Therefore, the thickness of the sheet P is strongly restricted, and the opening of the sheet P is suppressed. As a result, as shown in the upper diagram of FIG. 8, the inner sheet P is deformed to be wavy (undulating).

[0042] As shown in the lower diagram of FIG. 8, the saddle-folded sheet P is conveyed to the fold reinforcing unit 40 with the inner sheet P wavy. In the fold reinforcing unit 40, the sheet P is pressed by the pair of fold reinforcing rollers 46, 47 to perform the fold reinforcing process. However, the wavy sheet P resists the pressing force of the pair of fold reinforcing rollers 46, 47. Not all of the pressing force of the pair of fold reinforcing rollers 46, 47 acts on the crease of the sheet P. Therefore, the fold cannot be sufficiently reinforcing in the fold reinforcing unit 40. As a result, the sheet P opens after exiting the fold reinforcing unit 40, and the fold height of the sheet P increases. This reduces the processing quality of the saddle folding process of the sheet processing device 200. In particular, when a large number of sheets P are saddle-folded, the reduction in processing quality becomes more noticeable.

[0043] FIG. 7 is an explanatory diagram of the operation of the embodiment. As described above, the lower guide L of the embodiment is inclined so as to move away from the transport reference surface SS in the -X direction. The distance in the Z direction between the lower guide L and the upper guide U is wide in the -X direction and narrows in the +X direction. Therefore, as shown in the upper diagram of FIG. 7, the height of the sheet P transported in the +X direction is gradually restricted. The sheet P is folded from the crease at the leading edge. This makes it difficult for the inner sheet P to become wavy.

[0044] Like the lower guide L, the upper guide U is also inclined so as to move away from the transport reference surface SS in the -X direction. The distance in the Z direction between the lower guide L and the upper guide U becomes wider in the -X direction. This makes it difficult for the inner sheet P to become wavy.

[0045] The conveyed sheet P is influenced by gravity and tends to open more downward than upward. As described above, the lower guide L in this embodiment is farther from the conveying reference surface SS than the upper guide U. This relaxes the restriction imposed by the lower guide L on the sheet P. The lower guide L folds the sheet P without suppressing the downward opening of the sheet P. This makes it less likely that the inner sheet P will become wavy.

[0046] As shown in the lower diagram of FIG. 7, the sheet P that is folded flat without any waviness is transported to the fold reinforcing unit 40. Since the sheet P is not waviness, the entire pressing force of the pair of fold reinforcing rollers 46, 47 acts on the crease of the sheet P. Therefore, the sheet P is sufficiently folded and reinforcing in the fold reinforcing unit 40. After exiting the fold reinforcing unit 40, the fold height of the sheet P is reduced. This prevents a decrease in the processing quality of the saddle folding process of the sheet processing device 200. In particular, even when a large number of sheets P are saddle folded, a decrease in the processing quality can be prevented.

[0047] As described above in detail, the sheet processing apparatus 200 of the embodiment has the folding unit 35, the fold reinforcing unit 40, the upper guide U, and the lower guide L. The folding unit 35 folds the sheet P to form a crease. The fold reinforcing unit 40 folds the crease of the sheet P formed by the folding unit 35. In the conveying path 50 of the sheet P between the folding unit 35 and the fold reinforcing unit 40, the conveying reference plane SS, the orthogonal plane VS, the evaluation plane ES, the conveying reference line SL, the orthogonal line VL, and the second position Pb are defined as follows. The conveying reference plane SS is a plane along which the center of the sheet P in the thickness direction is conveyed. The orthogonal plane VS is a plane perpendicular to the X direction. The evaluation plane ES is a plane parallel to the X direction and perpendicular to the conveying reference plane SS. The conveying reference line SL is an intersection line between the conveying reference plane SS and the evaluation plane ES. The orthogonal line VL is an intersection line between the orthogonal plane VS and the evaluation plane ES. The second position Pb is a position in the +X direction from the first position Pa of the transport reference line SL. The upper guide U is disposed above the transport reference surface SS, and guides the transport of the sheet P along the upper guide line UL, which is the intersection line with the evaluation surface ES. The lower guide L is disposed below the transport reference surface SS, and guides the transport of the sheet P along the lower guide line LL, which is the intersection line with the evaluation surface ES. The intersection point between the orthogonal line VL passing through the first position Pa and the lower guide line LL is defined as the first intersection point Ca. The intersection point between the orthogonal line VL passing through the second position Pb and the lower guide line LL is defined as the second intersection point Cb. The intersection point between the orthogonal line VL passing through the first position Pa and the upper guide line UL is defined as the third intersection point Cc. The first distance Da between the first position Pa and the first intersection point Ca is greater than the second distance Db between the second position Pb and the second intersection point Cb. The first distance Da is greater than the third distance Dc between the first position Pa and the third intersection point Cc. This makes it possible to suppress a decrease in the processing quality of the sheet processing apparatus 200.

[0048] 5 is a schematic diagram of the periphery of the conveying path 50 in a first modified example of the embodiment. In the first modified example, the angle LA between the lower guide line LL and the conveying reference line SL is equal to the angle UA between the upper guide line UL and the conveying reference line SL. In the first modified example, the intersection point LP between the lower guide line LL and the conveying reference line SL is in the +X direction (downstream in the conveying direction of the sheet P) from the intersection point UP between the upper guide line UL and the conveying reference line SL. The intersection line LC between the lower guide surface LS and the conveying reference surface SS is in the +X direction from the intersection line UC between the upper guide surface US and the conveying reference surface SS.

[0049] As in the embodiment, in the first modified example, the first distance Da is greater than the second distance Db. That is, the lower guide L is inclined so as to move away from the transport reference surface SS in the -X direction. The third distance Dc is greater than the fourth distance Dd. That is, the upper guide U is inclined so as to move away from the transport reference surface SS in the -X direction. The first distance Da is greater than the third distance Dc. The second distance Db is greater than the fourth distance Dd. That is, the lower guide L is farther from the transport reference surface SS than the upper guide U.

[0050] As a result, waving is less likely to occur on the inner side of the sheet P in the conveying path 50. The sheet P is sufficiently folded and reinforced in the fold reinforcing unit 40. Therefore, deterioration in the processing quality of the sheet processing apparatus 200 can be suppressed.

[0051] 6 is a schematic diagram of the periphery of the conveying path 50 in a second modified example of the embodiment. In the second modified example, the lower guide L is a curved plate. The lower guide surface LS is a curved surface, and the lower guide line LL is a curved line. The lower guide L protrudes downward. That is, the plane that contacts the lower guide L is disposed below the lower guide L. As in the embodiment, the upper guide U is a flat plate. Alternatively, the upper guide U may be a curved plate that protrudes upward.

[0052] As in the embodiment, in the first modified example, the first distance Da is greater than the second distance Db. That is, the lower guide L curves away from the transport reference surface SS in the -X direction. The first distance Da is greater than the third distance Dc. The second distance Db is greater than the fourth distance Dd. That is, the lower guide L is farther from the transport reference surface SS than the upper guide U. As a result, waving is less likely to occur on the inner side of the sheet P in the conveying path 50. The sheet P is sufficiently folded and reinforced in the fold reinforcing unit 40. Therefore, deterioration in the processing quality of the sheet processing apparatus 200 can be suppressed.

[0053] As shown in FIG. 3, a sensor 52 and a film member 56 are provided on the transport path 50. The sensor 52 detects that the leading edge of the saddle-folded sheet P has reached a reference position on the conveying path 50, and outputs a detection signal. The second control unit 95 of the sheet processing apparatus 200 receives the detection signal from the sensor 52. The second control unit 95 stops conveying the sheet P a predetermined time after receiving the detection signal. As a result, the fold at the leading edge of the sheet P is positioned between the pair of fold reinforcing rollers 46, 47. Thereafter, the second control unit 95 causes the fold reinforcing unit 40 to perform a fold reinforcing process.

[0054] The sensor 52 has an actuator 53 that can come into contact with the leading edge of the saddle-folded sheet P. The actuator 53 is formed in a flat plate shape and can rotate around a rotation shaft 54. The rotation shaft 54 ​​is parallel to the Y direction and is disposed below the lower guide L. The actuator 53 passes through an opening in the lower guide L and extends close to the upper guide U. The actuator 53 is biased in a direction (-X direction) that blocks the conveying path 50.

[0055] The leading edge of the saddle-folded sheet P presses down the actuator 53 in the +X direction. When the actuator 53 rotates by a predetermined angle, the sensor 52 detects that the leading edge of the sheet P has reached the reference position of the conveying path 50.

[0056] The film member 56 is formed into a flat plate shape from a flexible material such as a resin film. The film member 56 is disposed in the -X direction of the actuator 53. The +Z direction end of the film member 56 is attached to the upper guide U. The -Z direction end of the film member 56 extends to near the intersection line between the actuator 53 and the lower guide L. The film member 56 guides the leading edge of the sheet P to the actuator 53.

[0057] The rigidity of a thick booklet in which many sheets P are saddle-folded is greater than the rigidity of film member 56. When the leading edge of the thick booklet comes into contact with film member 56, it pushes up film member 56 and moves in the +X direction. When the leading edge of the thick booklet moves a fifth distance in the +X direction after reaching actuator 53, actuator 53 rotates by a predetermined angle. As a result, sensor 52 detects that the leading edge of the thick booklet has reached the reference position of transport path 50.

[0058] The rigidity of a thin booklet in which a small number of sheets P are saddle-folded is smaller than the rigidity of the film member 56. When the leading edge of the thin booklet comes into contact with the film member 56, it moves downward along the surface of the film member 56. When the leading edge of the thin booklet moves a sixth distance in the +X direction after reaching the actuator 53, the actuator 53 rotates by a predetermined angle. The leading edge of the thin booklet presses the vicinity of the rotation shaft 54 ​​of the actuator 53, causing the actuator 53 to rotate. Therefore, even if the sixth distance is shorter than the fifth distance, the actuator 53 rotates by the predetermined angle. As a result, the sensor 52 detects that the leading edge of the thin booklet has reached the reference position of the transport path 50.

[0059] The smaller the rigidity of the booklet formed by saddle-folding multiple sheets P, the closer the film member 56 guides the leading edge of the booklet to the rotation shaft 54 ​​of the actuator 53. This allows the sensor 52 to detect that the leading edge of the booklet has reached the reference position of the transport path 50, regardless of the rigidity of the booklet.

[0060] 3, the rotation shaft 54 ​​of the actuator 53 is disposed below the lower guide L, and the film member 56 is attached to the upper guide U. Alternatively, the rotation shaft 54 ​​of the actuator 53 may be disposed above the upper guide U, and the film member 56 may be attached to the lower guide L. In other words, the actuator 53 and the film member 56 may be disposed opposite to the transport reference plane.

[0061] In the embodiment described above, the upper guide U and the lower guide L are flat plates. Alternatively, the upper guide U and the lower guide L may have multiple ribs aligned in the Y direction. The ridgelines of the ribs are parallel to the XZ plane. The upper guide U and the lower guide L guide the transport of the sheet P with the ridgelines of the multiple ribs. In this case, the ridgeline of the ribs of the upper guide U is the upper guide line UL, and the ridgeline of the ribs of the lower guide L is the lower guide line LL.

[0062] (Appendix 1) a folding unit for folding and creasing the sheet; a fold reinforcing unit that reinforcing the crease of the sheet formed by the folding unit; In the sheet conveying path between the folding unit and the fold-reinforcing unit, when a surface along which the central portion of the sheet in the thickness direction is conveyed is defined as a conveying reference surface, a surface perpendicular to the sheet conveying direction is defined as an orthogonal surface, a surface parallel to the conveying direction and perpendicular to the conveying reference surface is defined as an evaluation surface, a line of intersection between the conveying reference surface and the evaluation surface is defined as a conveying reference line, a line of intersection between the orthogonal surface and the evaluation surface is defined as an orthogonal line, and a position downstream in the conveying direction from a first position of the conveying reference line is defined as a second position, an upper guide arranged above the transport reference surface and configured to guide transport of the sheet along an upper guide line that is an intersection line with the evaluation surface; a lower guide disposed below the transport reference surface, guiding transport of the sheet along a lower guide line which is an intersection line with the evaluation surface, wherein when an intersection point between the orthogonal line passing through the first position and the lower guide line is defined as a first intersection point, an intersection point between the orthogonal line passing through the second position and the lower guide line is defined as a second intersection point, and an intersection point between the orthogonal line passing through the first position and the upper guide line is defined as a third intersection point, a first distance between the first position and the first intersection point is greater than a second distance between the second position and the second intersection point, and the first distance is greater than a third distance between the first position and the third intersection point. Sheet handling device. (Appendix 2) When the intersection point between the orthogonal line passing through the second position and the upper guide line is defined as a fourth intersection point, the third distance is greater than a fourth distance between the second position and the fourth intersection point; 2. The sheet processing device according to claim 1. (Appendix 3) The upper guide line is a straight line, and the lower guide line is a straight line. 3. The sheet processing apparatus according to claim 1 or 2. (Appendix 4) The angle between the lower guide line and the conveying reference line is larger than the angle between the upper guide line and the conveying reference line. 4. The sheet processing device according to claim 3. (Appendix 5) an intersection point between the lower guide line and the conveying reference line is located downstream in the conveying direction with respect to an intersection point between the upper guide line and the conveying reference line; 4. The sheet processing device according to claim 3. (Appendix 6) The fold reinforcing unit has a pair of fold reinforcing rollers that sandwich the fold of the sheet formed by the folding unit and rotate along a fold direction in which the fold extends. 6. The sheet processing apparatus according to claim 1, (Appendix 7) a sensor having an actuator capable of contacting the leading edge of the sheet and detecting that the leading edge of the sheet has reached a reference position of the conveying path; a film member attached to the upper guide or the lower guide and guiding the leading edge of the sheet to the actuator; 7. The sheet processing apparatus according to claim 1, (Appendix 8) the upper guide guides the conveyance of the sheet along a flat upper guide surface; The lower guide guides the conveyance of the sheet along a flat lower guide surface. 3. The sheet processing apparatus according to claim 1 or 2. (Appendix 9) an angle between the lower guide surface and the transport reference surface is larger than an angle between the upper guide surface and the transport reference surface; 9. The sheet processing device according to claim 8. (Appendix 10) an intersection line between the lower guide surface and the transport reference surface is located downstream in the transport direction from an intersection line between the upper guide surface and the transport reference surface; 9. The sheet processing device according to claim 8.

[0063] According to at least one of the embodiments described above, the lower guide L has a first distance Da that is greater than the second distance Db, and the first distance Da is greater than the third distance Dc. This makes it possible to suppress deterioration in the processing quality of the sheet processing apparatus 200.

[0064] Although some embodiments of the present invention have been described, these embodiments are presented as examples and are not intended to limit the scope of the invention. These embodiments can be implemented in various other forms, and various omissions, substitutions, and modifications can be made without departing from the spirit of the invention. These embodiments and their modifications are included in the scope of the invention and its equivalents described in the claims, as well as in the scope and spirit of the invention. [Explanation of symbols]

[0065] Ca...first intersection, Cb...second intersection, Cc...third intersection, Cd...fourth intersection, Da...first distance, Db...second distance, Dc...third distance, Dd...fourth distance, ES...evaluation surface, L...lower guide, LA...angle, LC...intersection line, LL...lower guide line, LP...intersection point, LS...lower guide surface, P...sheet, Pa...first position, Pb...second position, SL...conveying reference line, SS...conveying reference surface, U...upper guide, UA...angle, UC...intersection line, UL...upper guide line, UP...intersection point, US...upper guide surface, VL...orthogonal line, VS...orthogonal surface, 35...folding unit, 40...fold addition unit, 50...conveying path, 200...sheet processing device.

Claims

1. a folding unit for folding and creasing the sheet; a fold reinforcing unit that reinforcing the crease of the sheet formed by the folding unit; In the sheet conveying path between the folding unit and the fold-reinforcing unit, when a surface along which the central portion of the sheet in the thickness direction is conveyed is defined as a conveying reference surface, a surface perpendicular to the conveying direction of the sheet is defined as an orthogonal surface, a surface parallel to the conveying direction and perpendicular to the conveying reference surface is defined as an evaluation surface, a line of intersection between the conveying reference surface and the evaluation surface is defined as a conveying reference line, a line of intersection between the orthogonal surface and the evaluation surface is defined as an orthogonal line, and a position downstream in the conveying direction from a first position of the conveying reference line is defined as a second position, an upper guide arranged above the transport reference surface and configured to guide transport of the sheet along an upper guide line that is an intersection line with the evaluation surface; a lower guide disposed below the transport reference surface, guiding transport of the sheet along a lower guide line which is an intersection line with the evaluation surface, wherein when an intersection point between the orthogonal line passing through the first position and the lower guide line is defined as a first intersection point, an intersection point between the orthogonal line passing through the second position and the lower guide line is defined as a second intersection point, and an intersection point between the orthogonal line passing through the first position and the upper guide line is defined as a third intersection point, a first distance between the first position and the first intersection point is greater than a second distance between the second position and the second intersection point, and the first distance is greater than a third distance between the first position and the third intersection point. Sheet handling device.

2. When an intersection point between the orthogonal line passing through the second position and the upper guide line is defined as a fourth intersection point, the third distance is greater than a fourth distance between the second position and the fourth intersection point; The sheet processing apparatus according to claim 1 .

3. The upper guide line is a straight line, and the lower guide line is a straight line. The sheet processing apparatus according to claim 1 .

4. The angle between the lower guide line and the conveying reference line is larger than the angle between the upper guide line and the conveying reference line. The sheet processing apparatus according to claim 3 .

5. an intersection point between the lower guide line and the conveying reference line is located downstream in the conveying direction from an intersection point between the upper guide line and the conveying reference line; The sheet processing apparatus according to claim 3 .

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