JP6678988B2 - Sheet folding apparatus Image forming apparatus and sheet folding method including the same - Google Patents

Description

  The present invention relates to a sheet folding apparatus that folds sheets discharged from an image forming apparatus such as a copying machine and various printers, and in particular, a sheet folding apparatus that can perform compact folding, an image forming apparatus including the sheet folding apparatus, and a sheet folding method. Involved in

Generally, a folding device that performs a folding process on a sheet carried out from an image forming apparatus at a predetermined position is widely known.
By the way, in recent years, there has also been provided a post-processing device, for example, a device that is arranged in front of a binding device and is connected to an image forming apparatus to perform a sheet folding process.

  For example, in Japanese Patent Application Laid-Open No. 2004-242242, there are three conveyance paths which are located between the image forming section and the post-processing device and which guide the image-formed sheet conveyed from the image forming section, and three pressure-contacting rollers which are located in the conveyance path. A folding device in which a folding roller and a leading end stopper that regulates the leading edge of the sheet and a folding blade that pushes the regulated sheet between the three folding rollers are shown. Then, this folding apparatus is a sheet folding apparatus that repeats switchback conveyance of sheets in sequence and sequentially passes through three folding rollers to perform folding processing.

Further, also in Patent Document 2, the image-formed sheet discharged from the image forming unit is arranged in front of a post-processing device that binds sheets, and the image-formed sheet is once conveyed to a curved conveying path. A sheet folding apparatus is shown in which a folding member presses three folding rollers that are pressed against each other by a deflecting member to perform a folding process.

Japanese Patent No. 5218836 Japanese Patent No. 5595009

The sheet folding apparatus shown in the above-mentioned Patent Documents 1 and 2 requires a relatively long conveyance path for holding the length of the sheet to be folded. Further, in any of the sheet folding apparatuses, the sheet is fed in one direction and is conveyed back to the three rollers while being switched back to carry out the folding process.
By the way, since the folding device shown in Patent Document 2 is configured by a conveying path that is curved above and below three rollers, it is relatively smaller than the folding device of Patent Document 1 that is configured by a linear conveying path. However, it is necessary to provide a conveying path over the entire length of the curved sheet.

However, basically, there is a conveyance path corresponding to the sheet conveyance length, and since the sheet is folded back while being switchback-conveyed, a shift during conveyance and a complicated sheet conveyance path are required.
Particularly, in order to correspond to a so-called in-body type in which a recent device for processing a sheet is installed in a paper discharge space between a reading device arranged above the image forming unit, a small size is achieved so as to be arranged in this space. Was not done.

  The present invention has been made based on the above problem, does not require a conveyance path along the conveyance length of the sheet to be folded, and does not perform a complicated switchback conveyance of the sheet, and is relatively compact. An object of the present invention is to provide a sheet folding device that can easily perform folding processing.

The present invention adopts the following configurations in order to solve the above problems.
A sheet folding apparatus to adjust the folding of the sheet, and conveying means for conveying a predetermined conveying direction intersecting the sheet width direction, and a holding member that holds the sheet conveyed by said conveying means in a substantially tubular shape, the holding a shift member substantially to a flat shape to the outer peripheral surface of the substantially cylindrical shape sheet held in member is pressed against the direction crossing the width direction of the sheet, further the cross sheets becomes substantially flat by the shift member A sheet folding device including a discharging unit that presses in a direction and discharges in the width direction.

  According to the present invention, a folding mechanism that holds a sheet in a substantially cylindrical shape and ejects the sheet while pressing the sheet into a substantially flat shape is performed without using a conveyance path along the sheet length or three folding rollers that are in pressure contact. It is possible to provide a relatively compact sheet folding device capable of performing.

FIG. 3 is an explanatory diagram showing an overall configuration in which a folding unit that is a sheet folding apparatus according to the present invention and an image forming apparatus are combined. FIG. 3 is an explanatory diagram showing an overall configuration in which a folding unit according to the present invention is combined with a tray unit having an extended range of elevation and an image forming apparatus. FIG. 2 is an explanatory view showing a sheet processing apparatus including the folding unit shown in FIG. 1. The perspective view which shows the principal part inside the folding unit of FIG. Sectional explanatory drawing of the folding unit of FIG. 4 is a plan view of the folding mechanism of the folding unit of FIG. FIG. 7 is a perspective view of a shift unit before pressing the substantially cylindrical sheet of FIG. 6. FIG. 8 is an explanatory diagram showing a drive relationship between a shift unit and a folding roller shown in FIGS. 4 to 7. FIG. 8 is a cross-sectional explanatory view in which a substantially tubular sheet is pressed into a flat shape by the shift portion of FIG. 7. The perspective view of the shift part which pressed the substantially cylindrical sheet of FIG. 9 in a substantially flat shape. FIG. 11 is a perspective view showing a state in which the substantially flat sheet of FIG. 10 is discharged while being folded. 12A and 12B are state diagrams showing a sheet to be folded according to FIGS. 4 to 11, FIG. 12A shows a state in which the sheet is held in a tubular shape, and FIG. 12B is an explanatory diagram showing a state in which the sheet is folded. FIG. 6 is a perspective view showing a state in which folded sheets discharged from a folding unit while being folded by a folding roller are accumulated. FIG. 6 is an explanatory cross-sectional view that forms a tubular sheet by winding the sheet in a substantially tubular shape in a direction opposite to that in FIG. 5. The mechanism explanatory drawing of the guide gate of FIG. 5 and FIG. 16A and 16B are views for explaining the relationship between the front and back sides of the sheet in a substantially cylindrical winding state, and FIG. 16A is an explanatory view of the state in which the back side is wound counterclockwise as shown in FIG. FIG. 16B is an explanatory view of a state in which the winding surface is turned clockwise in FIG. FIG. 14 is a state diagram showing a sheet to be folded according to FIG. 14, FIG. 14A shows a state in which the sheet is held in a substantially tubular shape, and FIG. 14B is an explanatory diagram showing a state of the folded sheet that has been folded. Explanatory drawing of the control structure in the whole structure of FIG. 1 and FIG.

Hereinafter, a sheet processing apparatus B including a folding unit 31 as a sheet folding apparatus according to the present invention and an image forming apparatus A to which the sheet processing apparatus B is attached will be described with reference to the drawings.
FIG. 1 is an explanatory diagram showing the overall configuration of a sheet processing apparatus B including a folding unit 31 according to the present invention, an image forming apparatus A, and an image forming apparatus A. FIG. 2 is an explanatory view showing an overall configuration in which the sheet processing apparatus B having the folding unit 31 according to the present invention and the elevating range of the stacking tray 90 is expanded and the image forming apparatus A are combined.

[Image forming apparatus A]
An image forming apparatus A shown in FIGS. 1 and 2 uses an electrophotographic system, and has a sheet feeding unit including three sheet feeding cassettes 1a, 1b, and 1c below the image forming unit 2 and containing sheets. When the sheet processing apparatus B is not attached, the image reading unit 20 is arranged above the image forming unit 2 as a paper discharge space. Therefore, when arranging the sheet processing apparatus B, it is a so-called in-body type apparatus that utilizes the above-mentioned paper discharge space.

The image forming section 2 employs a tandem system using an intermediate transfer belt. That is, four color components (yellow 2Y, magenta 2M, cyan 2C, black 2BK) are used. For example, in yellow 2Y, a photosensitive drum 3a as an image carrier and a charging roller that charges this photosensitive drum 3a. It has a charging device 4a consisting of the above, and an exposure device 5a which uses the image signal read by the image reading device 20 as a latent image. Further, a developing device 6a for forming the latent image formed on the photosensitive drum 3a as a toner image, and a primary transfer roller 7a for primarily transferring the image on the photosensitive drum 3a formed by the developing device 6a onto the intermediate transfer belt 9 Is equipped with. This configuration is primarily transferred to the intermediate transfer belt 9 for each color component. The color components remaining on the photosensitive drum 3a are collected by the photosensitive cleaner 8a and prepared for the next image formation. These are the same for other color components as shown in FIGS.

By the way, the image on the intermediate transfer belt 9 is transferred onto the sheet fed from the sheet feeding section 1 by the secondary transfer roller 10, and the image is melted and fixed on the sheet by the fixing device 12 by the pressing force and the heat amount. The superimposed color components remaining on the intermediate transfer belt 9 are removed by the intermediate belt cleaner 11 to be prepared for the next transfer.

The sheet thus image-formed is directed to the main body discharge port 16 by the main body discharge roller 14, but when images are formed on both sides of the sheet, the sheet once conveyed to the sheet processing apparatus B side is switched by the switching gate 15. The sheet is moved back, conveyed to the circulation path 17, and again fed to the image forming unit 2 to form an image on the back side of the sheet.
The sheet thus image-formed on one side or both sides is conveyed to the sheet processing apparatus B including the folding unit 31 through the main body discharge roller 14.

An image reading device 20 is arranged above the paper discharge space above the image forming unit 2. Here, the document placed on the document stacker 25 is fed to the platen 21 by the document feeding device 24, and the fed document is irradiated with the scan unit 22 so that it is sequentially read by a photoelectric conversion element (for example, CCD), and is illustrated. The image is accumulated in the non-data storage unit. The image formation of the accumulated image on the sheet by the image forming unit is as described above.

[Sheet processing device B]
Next, the sheet processing apparatus B arranged in the paper discharge space below the image reading apparatus 20 above the image forming unit 2 in FIGS. 1 and 2 will be described. As part of the sheet processing apparatus B, a folding unit 31 as a sheet folding apparatus for folding a sheet according to the present invention is provided.
The sheet processing apparatus B sends a sheet discharged from the main body discharge port 16 to a downstream side apparatus, or guides a sheet to be switched back to form image formation on both sides, and a sheet for example. A folding unit 31 that folds in three, a binding unit 32 that temporarily mounts the sequentially formed image-formed sheets on the processing tray 76 and binds them as a bundle with a stapler 80, and a sheet bundle or binding that is bound by the binding unit 32. A tray unit 33 having a stacking tray 90 that stacks and ascends and stacks sheets that are not discharged is arranged.
Note that the guide unit 30, the folding unit 31, and the binding unit 32 having the tray unit 33 that constitute the sheet processing apparatus B can be selectively arranged. For example, only the binding unit 32 or the folding unit can be placed, It is possible to omit it.

In the tray unit 33 having the stacking tray 90 that moves up and down, in FIG. 1, the stacking unit 90 is placed on the lift rack 100 at a position within L1a from the staple of the apparatus frame 29 of the image forming apparatus A in the binding unit 32. It is designed to move up and down. Therefore, since the sheet processing apparatus B is arranged in the paper discharge space, the entire image forming apparatus A becomes compact, and, for example, the stacking tray 90 that moves up and down when only the binding unit 32 is placed in the paper discharge space is also discharged. It is located in space and can be made more compact.

On the other hand, in the apparatus shown in FIG. 1 in this case, the moving range of the stacking tray 90 ascending and descending is the range of the L1t range to the upper surface of the apparatus frame 29. Generally, the L1t range is set to about 500 to 1000 sheets as the stacking amount of sheets, and when the stacking amount is more than this, the image forming apparatus A is stopped and the sheets placed on the stacking tray 90 are taken out. Or, the sheet processing apparatus B which can be externally attached to a completely different apparatus frame 29 is replaced.

Therefore, the stacking tray 90 according to the present invention is a sheet processing apparatus in which an extension rack 102 that can easily extend the lifting range is added to the conventional lifting rack 100 (lifting rail 99) to increase the amount of sheets stacked on the stacking tray 90. B and the image forming apparatus are shown in FIG. The mechanism for extending the sheet will be described later, but by adding the extension rack 102 (extension rail 101), the stacking amount of the sheets can be increased by about 500 to 1000 sheets.

Here, in order to add the above-mentioned extension rack 102 and allow the stacking tray 90 to move down to the extension rack 102, first, the guide unit 30 having the length L1y in the conveyance method direction in FIG. The guide unit 30 having a length of L2y in the conveyance direction is replaced. The length of L2y here is such that the distance L1a between the side surface of the binding device and the side surface of the device frame 29 in FIG. 1 is eliminated and the elevating rack 100 and the extension rail 101 communicate with each other.
The folding unit 31, the binding unit 32, the tray unit 33 attached thereto, and the lifting mechanism for the stacking tray 90 of the tray unit 33 will be described below, and then the extension rack 102 is installed. The extension rail including will be described.
Although the guide unit 30 is shown as a unit for guiding the conveyance of the sheet for adjusting the length in the conveyance direction of the sheet processing apparatus B, a punch unit for punching the sheet and a stamp unit for stamping are provided in this unit. Alternatively, embossing units that give unevenness to the sheet may be arranged alone or in combination.

[Folding unit 31]
Here, the folding unit 31 which is the sheet folding apparatus according to the present invention will be described. The folding unit 31 will be briefly described here, and the details will be described with reference to FIG. 4 and subsequent figures.
FIG. 3 is an enlarged explanatory view of a folding unit 31, a binding unit 32, and a tray unit 33 attached to the folding unit 31, which are a part of the sheet processing apparatus B of FIG. The sheet processing apparatus B of FIG. 2 is similar to that of FIG. 3 except that the moving range of the stacking tray 90 is expanded.
First, an entrance roller 45 and an exit roller 47 are arranged in the lower folding conveyance path 43 of the path extending from the main body discharge port 16 to the switchback path 35 of the guide unit 30 and the conveyance path 37. A switching flapper 49 is provided between the entrance roller 45 and the exit roller 47, and the switching flapper 49 performs a folding process at the substantially tubular folding section 50 without transporting the sheet to the subsequent binding unit 32. ing.
A folding switchback path 41 communicating with the guide unit 30 shown in FIGS. 1 and 2 is provided on the upper stage.

The substantially tubular folding portion 50 has a first gate that determines a carry-in roller 51, which is a conveying roller of the present invention that carries in a sheet of the substantially tubular folding portion 50, and a winding direction of the sheet around the substantially tubular folding portion. 53 and the second gate 55 are adapted to be selectively moved to the operating position. For example, the first gate 53 winds the substantially cylindrical shape forming portion 57 in a counterclockwise direction in the drawing in a substantially cylindrical shape. The substantially tubular shape forming portion 57 is made of a deformable sheet member, and the sheets are wound around the approximately tubular shape in a state where, for example, the three surfaces overlap. When the shift members 60 and 61 located on both sides in the state of being wound around the substantially tubular shape forming portion are shifted toward each other, the wound sheet also becomes a flat shape with a vertical elliptical cross section. In this state, a folded sheet is obtained by pulling out the sheet wound by a cylindrical roller (not shown). Details will be described later with reference to FIG.
Here, the “substantially tubular shape” referred to in the present invention means a substantially tubular shape having a shape shown in FIG. 12A, FIG. 16 or FIG. a) and FIG. 12 (b) or FIG. 17 (a) and FIG. 17 (b), a substantially tubular shape is pressed from both sides by an elliptical strip having a substantially cross section, and the lateral direction is narrow and the tubular shape extends in the vertical direction. A sheet having a shape with a narrower interval than the shape is referred to. The "outer peripheral surface" refers to a substantially cylindrical arc surface, and the outer peripheral edge refers to an edge in the sheet width direction that intersects the winding direction.

[Binding unit 32]
Subsequently, the binding unit 32 that binds the sheets conveyed from the folding unit 31 without performing the folding process in the folding unit 31 in FIG. 3 will be described.
A binding switchback path 65 communicating with the folding switchback path 41 is provided at the upper stage of the binding unit 32, and a transport roller 69 is disposed on the inlet side and a discharge roller 70 is disposed on the outlet side. The binding switchback path 65 functions as a path for switching back to form an image on the back surface of the image forming unit 2, and if necessary, double-sided sheets such as thick sheets and sheets not suitable for the binding process are located above the tray unit 33. It is also possible to discharge to the escape tray 34 by the discharge roller 70. The folding switchback path 41 and the binding switchback path 65 may use the top cover of each unit as a switchback path.

  Below the binding switchback path 65, a binding conveyance path 67 communicating with the folding conveyance path 43 of the folding unit 31 is provided. A binding carry-in roller 72 and a carry-out roller 74 that discharges the sheet to the processing tray 76 or the stacking tray 90 are provided on the entrance side of the binding and conveying path 67. When the sheets discharged from the carry-out rollers 74 are temporarily placed on the processing tray 76 to form a bundle, the sheets discharged by the bundle discharge roller 86 that also functions as the discharge of the bundle are nipped in the counterclockwise direction ( The sheet is conveyed until the sheet comes into contact with the reference surface 79 by rotating the scraping roller 78 rotating in the counterclockwise direction in cooperation with this. At the same time, the pair of aligning plates 84 located in the sheet width direction of the processing tray 76 are brought into contact with the side edges of the sheets to align the sheets.

This is repeated until the number of sheets to be bound is reached, and when the number of sheets to be bound is reached, the stapler 80 is moved to a predetermined position of the moving table 82 and the binding process is performed. The sheet bundle bound to the designated portion by the stapler 80 moves the reference surface 79 (not shown) to the stacking tray 90 side, and the elevating bundle discharge roller 86a is attached to the lower bundle discharge roller 86b fixed to the discharge side of the processing tray 76. The sheet bundle is discharged to the stacking tray 90 by pressing.

[Tray unit 33]
The sheet bundle discharged by the bundle discharge roller 86 or the next sheet is stacked by a tray unit 33 having a stacking tray 90 that moves up and down. The stacking tray 90 is designed to be lifted and lowered by engaging and rotating an elevating pinion 98 of the accumulating tray 90 with an elevating rack 100 which forms a part of an elevating rail 99 which is a moving rail described later. The elevating pinion 98 is driven by an elevating motor 95 located in an elevating motor installation section 94 below the stacking tray 90 via a transmission gear 97 and the like.
As described above, the range of raising and lowering of the stacking tray 90 shown in FIG. 3 is the L1t range because the sheet processing apparatus B including the binding unit 32 is located within the body L1a from the side of the apparatus frame 29. Has become. The extension range of the stacking tray 90 can be expanded by providing the extension rail 101 shown in FIG. 2, and the stacking amount of sheets can be increased.
The extension rail 101 is fixed to the apparatus frame 29 of the image forming apparatus A and the extension rail mounting portion 141 that is fixed to the sheet processing apparatus B, but this mounting may be performed only on the sheet processing apparatus B.

From here, the folding unit 31 as a sheet folding device that constitutes a part of the sheet processing apparatus B will be described in detail. FIG. 4 is a perspective view of the substantially tubular folding portion (folding processing portion) 50 of the folding unit 31, and FIG. 5 is a cross-sectional explanatory view of the folding unit 31.
[Substantially tubular folding part (folding part) 50]
As shown in FIGS. 4 and 5, the substantially tubular folding section (folding processing section) 50 carries the folding conveyance path 43 from the entrance roller 45 from the folding entrance 104 communicating with the folding conveyance path 43 of the guide unit. An exit roller 47 is located on the exit side of the folding conveyance path 43 to feed the sheet to the subsequent binding unit 32. The sheet carried in is detected by the sheet carry-in sensor Sen1.
When the sheet is conveyed to the folding processing unit 50 that is a substantially tubular folding unit that forms a substantially tubular shape without sending the sheet to the binding unit 32, the switching flapper 49 that is moved by a solenoid (not shown) is located at the position shown in FIG. Move to. As a result, the sheet conveyed by the entrance roller 45 is guided to the folding introduction path 108 and carried into the substantially tubular shape forming portion 57. In FIG. 4, the substantially tubular shape forming portion 57 that constitutes the approximately tubular folding portion 50 is located below the entrance roller 45 and the exit roller 47 of the folding unit 31, and the sheet is carried in by the carry-in roller 51 near the center thereof. It is shown as a perspective view that the is formed into a substantially cylindrical shape.

[Substantially tubular shape forming part 57]
The substantially tubular shape forming portion 57 forms the sheet into a substantially tubular shape and holds the sheet in a substantially cylindrical shape having a substantially columnar shape as shown in FIG. 12A or 17A, for example. In FIG. 5, the first gate 53 on the left side of FIG. 5 is positioned as a guide gate between the carry-in roller 51 and the substantially cylindrical shape forming portion 57, whereby the sheet is rotated counterclockwise in the drawing (counterclockwise / CP ( L)).
The substantially tubular shape forming portion 57 includes an outer guide 57a made of a flexible sheet material (for example, a polyester film sheet) whose end is attached to the frame of the folding unit 31, and a shift described later with a space provided therebetween. Each of the members 60 and 61 is composed of an inner guide 57b partially attached to the rear end pushing members 118 and 119. The inner guide 57b is also made of the same material as the outer guide 57a, and is deformed when an external force is applied to the outer guide 57a and the inner guide 57b.
Although only the outer guide is shown in FIG. 4 for the sake of convenience, only the outer guide may be used depending on the sheet, and the point is that the sheet conveyed by the carry-in roller 51 is formed into a substantially cylindrical shape, and this shape has a force. Any material and shape that can be deformed by adding

[Shift member (left shift portion 60, right shift portion 61)]
Next, a shift member (left side) that deforms the sheet into a substantially flat shape by pressing the sheet having the substantially cylindrical shape in the above-described substantially cylindrical shape forming portion 57 in a direction intersecting the sheet width direction (a direction crossing the substantially cylindrical shape). The shift unit 60 and the right shift unit 61) will be described.
First, in the left shift portion 60, a left shift plate 114 made of a flat plate press member extends in the seat width direction. In this shape, the right shift portion 61 is also provided with a right shift plate 116 made of a flat plate press member.

As shown in FIG. 5, these are shifts that are close to a shift plate release position SO that receives a sheet having a substantially tubular shape in the substantially tubular shape forming portion 57 and deform the substantially tubular shape into a substantially flat shape having an elliptical cross section. It is configured to approach and separate from the plate pressing position SC position.
In this structure, one end is supported by the left link shaft 110J on the frame of the folding unit 31 at the front and rear two places, and the other end is supported on the left shift plate 114 by the left shift plate support shaft 114J as shown in FIG. The left link portion 110 is configured to approach and separate from each other. The right shift plate 116 is also pivotally supported by the right link shaft 112J, and the other end is moved by the right link portion 112 that supports the right shift plate 116 by the right shift plate support shaft 116J.
Due to this link mechanism, the left shift plate 114 of the left shift unit 60 and the right shift plate 116 of the right shift unit 61 move close to and away from the shift plate release position SO and the shift plate pressing position SC.

Further, each of the shift members (the left shift portion 60 and the right shift portion 61) is composed of an L-shaped member, and a substantially cylindrical sheet is formed into a substantially flat shape, and when the sheet is moved in the discharging direction, It has a rear end extruding member (a left rear end extruding portion 118 and a right rear end extruding portion 120) that engages with the rear end edge in the discharge direction and extrudes.
Further, folding rollers (left folding roller 132, right folding roller 136) which can be separated from and contact with each other sandwich the folded sheet exit 145 on the discharge side pushed by the shift members (left shift portion 60, right shift portion 61). It is located on this side. The left folding roller 132 and the right folding roller 136 are pressed against each other to form a substantially flat sheet into a folded sheet shown in FIGS. 12 (b) and 17 (b). The left folding roller 132 and the right folding roller 136 also function as a discharge row that discharges the folded sheet from the folding unit 31.
In this embodiment, the left folding roller 132 and the right folding roller 136 have an overlap of about 1/3 when they are substantially cylindrical, and thus are slightly longer than 1/3 of the sheet length. It is set. This can be made more compact than a conventional folding device that is set longer than the entire area in the sheet width direction.

The configuration of the shift member (left shift portion 60, right shift portion 61) and folding rollers (left folding roller 132, right folding roller 136) and the drive mechanism thereof will be described with reference to FIGS. 6 to 8.
FIG. 6 is a plan explanatory view of the shift portion (left shift portion 60, right shift portion 61) of the folding unit 31, FIG. 7 is a perspective view of the left shift portion 60, right shift portion 61 of this figure, and FIG. 6 is a drive explanatory diagram including a left folding roller 132 and a right folding roller 136. FIG.

[Rear end extruded part of shift member]
In FIG. 6, as described above, the shift members (the left shift portion 60 and the right shift portion 61) are each formed of an L-shaped member, and the substantially cylindrical sheet is formed into a substantially flat shape, and the sheet is discharged in the discharge direction. As a plan view, it has a rear end extruding member (a left rear end extruding portion 118, a right rear end extruding portion 120) that engages with the rear end edge of the sheet in the sheet discharge direction and is extruded when moving to the sheet. It is shown. Further, FIG. 7 shows a perspective view of only the shift member (the left shift portion 60, the right shift portion 61).
As can be understood from these figures, the left shift plate 114 of the left shift unit 60 and the right shift plate 116 of the right shift unit 61 are shifts positioned so as to support the seat in the substantially tubular shape forming unit 57 in an approximately tubular shape. It is also shown that it is located at the plate release position SO and the shift plate pressing position SC that presses the substantially cylindrical sheet from the direction intersecting the width direction to make it substantially flat.

At the shift plate release position SO, the left rear end push-out portion 118 and the right rear end push-out portion 120 are located in a substantially linear shape. When the sheet has completely entered the substantially tubular shape forming portion 57 and becomes a substantially tubular shape, the sheet is deformed and moved to the shift plate pressing position SC. At this position, the left rear end pushing portion 118 and the right side are pushed out. The rear end push-out parts 120 are formed in a comb shape so as to overlap each other (see FIG. 7). This shape has this shape so that they do not collide with each other at the shift plate pressing position SC and that they are sufficiently close to each other in order to make them substantially flat.

When the shift members (the left shift portion 60 and the right shift portion 61) are moved from the shift plate release position SO to the shift plate pressing position SC, the left rear end push-out portion 118 and the right rear end push-out portion 120 are left-folded. The roller 132 and the right folding roller 136 are adapted to move to the folded sheet exit 145 side. This is because the left shift plate 114 is on the left link portion 110 that rotates about the left link shaft 110J and the right shift plate 116 is on the right link portion 112 that rotates about the right link shaft 112J. Results from being rotatably mounted.
Therefore, when the shift member (left shift portion 60, right shift portion 61) moves from the shift plate release position SO to the shift plate pressing position SC, the folded sheet outlet 145 of this shift member (left shift portion 60, right shift portion 61). The side end also moves from the outlet separation position AO to the outlet proximity position AC. By this operation, the sheet supported in the substantially tubular shape forming portion 57 in the approximately tubular shape is deformed in a substantially flat shape, and is moved between the left folding roller 132 and the right folding roller 136 while being deformed in a substantially flat shape. It will be.

[Folding roller (left folding roller 132, right folding roller 136)]
As described above, the left folding roller 132 is arranged in the vicinity of the folded sheet exit 145 on the side opposite to the left rear end pushing section 118, and the right folding roller 136 is arranged on the side opposite to the right rear end pushing section 120. There is. The left folding roller 132 and the right folding roller 136 are also separated from each other so as to move between a folding roller separation position RR for receiving a flattened sheet and a folding roller pressing position RA for mutually pressing and folding. Is configured. Therefore, the left folding roller 132 and the right folding roller 136 are moved between the left folding roller 132 and the right folding roller 136 to a position where the sheet, which is becoming substantially flat by the shift member (the left shift portion 60, the right shift portion 61), is sandwiched. The right folding roller 136 is pressed to rotate.

Here, a drive mechanism including the left shift unit 60, the right shift unit 61, the left folding roller 132, and the right folding roller 136 will be described with reference to FIG.
First, the carry-in roller 51 includes a rear side frame (not shown) of the folding unit 31 and a left roller support arm 124 supported on the front side (folded sheet discharge side) so that the left roller shaft 130 and the right roller support arm 126 form a right side. A roller shaft 128 is supported. As a result, the carry-in roller 51 is driven by the carry driving motor 170 together with the entrance roller 45 and the exit roller 47 shown in FIG.

[Structure of shift member and drive mechanism]
The shift members (the left shift portion 60 and the right shift portion 61) move by rotating a sector gear 183 that is integrally provided in the left link portion 110 that moves the left shift plate 114. In FIG. 8, the drive mechanism of the left shift plate 114 of the left shift unit 60 is shown for convenience of illustration.
That is, the drive of the approach / separation motor 174 of the shift plate is transmitted to the transmission worm gear 182 via the transmission gear 181. Due to the drive rotation of the transmission worm gear 182, the fan gear 183 described above is rotated, and the left link portion 110 can be moved between the shift plate release position SO and the shift plate pressing position SC.
Drive is transmitted at a lower position where the shift members (the left shift portion 60 and the right shift portion 61) overlap each other, and the right shift portion 61 also moves in synchronization with the same configuration.

[Folding roller structure and drive mechanism]
Next, a mechanism for separating and contacting the folding rollers (the left folding roller 132 and the right folding roller 136) and a driving rotation mechanism for folding a substantially flat sheet will be described.
First, the folding rollers are separated from each other by placing the left folding roller shaft 133 of the left folding roller 132 and the right folding roller shaft of the right folding roller 136 on the upper pulleys 193 and 195 at a position where they are opposed to each other in the vertical axial direction. The moving belt 191 and the lower moving belt 192 stretched around the lower pulleys 194 and 196 are individually provided on respective shaft support portions 197.
Therefore, when the folding roller separating / contacting motor 178 is driven, the left folding roller 132 and the right folding roller 136 can be moved in a direction in which they are pressed against each other by one rotation, and can be moved in a direction in which they are separated from each other by the other rotation. The rotation arrows between the upper pulley 193 and the lower pulley 194 in FIG. 8 move in the directions in which they are pressed against each other.

Further, the left folding roller 132 and the right folding roller 136 are attached to shafts for driving the folding roller separation / contact motor 178, the upper pulley 193, and the lower pulley 194 so that a predetermined pressure contact force can be obtained for aligning the sheets. The intermediate gear 199 shown in the enlarged view of the chain double-dashed line is provided between the transmission gear 198 and the transmission gear 198.
The intermediate gear 199 is composed of two gears, namely, an outer drive gear 199a to which the drive of the folding roller separation / contact motor 178 is directly transmitted and a spring receiving gear 199e which is coaxial with this gear and engages with the transmission gear 198e. . A spring 199c interposed in a spring receiving portion 199b cut out in the driving gear 199a is arranged between the driving gear 199a and the spring receiving gear 199e. One end of the spring 199c is in contact with the inner wall of the drive side gear 199a by the spring receiver 199b, and the other end is in contact with the spring receiving portion integrally formed with the spring receiving gear 199e.

With this configuration, when the left folding roller 132 and the right folding roller 136 are not in contact with each other, the spring 199c rotates without being compressed. When the left folding roller 132 and the right folding roller 136 come into contact with each other, the drive side gear 199a compresses the spring 199c and drives it. The compression of the spring 199c acts as a force for pressing the left folding roller 132 and the right folding roller 136 into contact with each other, and a pressing force for folding the sheet is generated.
Although the folding roller separating / contacting motor 178 is shown on the discharge side in FIG. 8, it is arranged below the folding roller as a device.

Next, the configuration for rotationally driving the left folding roller 132 and the right folding roller 136 in the discharge direction will be described with reference to FIG.
The left folding roller 132 and the right folding roller 136 are driven by a folding roller drive motor 176. The driving of the folding roller drive motor 176 rotationally drives the square shaft 185 extending in the same direction as the lower moving belt 192 via the transmission gear. The rotation of the square shaft 185 causes the left sliding worm gear 187 and the right sliding worm gear 188 to rotate. As a result, the left sliding worm gear 187 drives the left folding roller gear 134 of the left folding roller 132, and the right sliding worm gear 188 drives the right folding roller gear 138 of the right folding roller 136.
In this case, even if the left folding roller 132 and the right folding roller 136 move between the roller pressing position RA where the left folding roller 132 and the right folding roller 136 are in pressure contact with each other and the roller separation position RR separated from each other, the drive transmission is formed by the square shaft 185. Can be transmitted by sliding.

[Pressing the substantially cylindrical sheet to a flat shape]
A state in which the sheet held in the substantially tubular shape in FIGS. 4 and 5 is pressed into a substantially flat shape by the 7 shift members (the left shift portion 60 and the right shift portion 61) will be described with reference to FIGS. 9 and 10.
As shown in FIG. 9, the sheet formed in the substantially tubular shape by the approximately tubular shape forming portion 57 is driven by the above-mentioned approach / separation motor 174 of the shift plate to move the left shift plate 114 and the right shift portion of the left shift portion 60. The right shift plate 116 of 61 moves from the shift plate release position SO to the shift plate pressing position SC which is close to each other. Due to the movement to the shift plate pressing position SC, the outer guide 57a and the inner guide 57b of the substantially tubular shape forming portion 57 are flexible sheet film materials, so that they have a substantially flat shape extending downward as shown in the figure. change. As a result, the sheet is held and the sheet is also changed from the substantially cylindrical shape to the substantially flat shape. At the time of this change, since the rear end of the sheet held in the substantially tubular shape is regulated by the carry-in roller 51, the sheet changes to an elliptical shape extending downward and becomes a substantially flat shape.
Although the inner guide 57b of the substantially tubular shape forming portion 57 is omitted in this figure, the inner guide 57b is also similarly deformed. Further, as described above, the inner guide 57b may be omitted.

FIG. 10 is a perspective view of the shift member (left shift portion 60, right shift portion 61) of FIG. In this figure, the left link part 110 and the right link part 112 of FIG. 7 are moved to move the left shift plate 114 and the right shift plate 116 from the shift plate release position SO to the shift plate pressing position SC, and the sheet is substantially cylindrical. It shows a state in which the shape changes to a substantially flat shape. This shows the same state as the diagram in which the left link portion 110 and the right link portion 112 of FIG. 6 already described move from the broken line position to the solid line position.
The movement of the shift members (the left shift portion 60 and the right shift portion 61) causes the substantially cylindrical sheet to be deformed into a substantially flat shape, and the folding rollers (the left folding roller 132 and the right folding roller) at the roller separation position RR. 136) and move. After the substantially flat sheet is positioned on the left folding roller 132 and the right folding roller 136, these are moved to the roller pressure contact position RA by driving the folding roller separation / contact motor. In this way, the sheet is conveyed by the carry-in roller 51 and is formed into a substantially cylindrical shape by the substantially cylindrical shape forming portion 57. Next, the shift members (the left shift portion 60 and the right shift portion 61) are deformed from the substantially cylindrical shape to the substantially flat shape and moved between the left folding roller 132 and the right folding roller 136.
Further, the left rear end push-out portion 118 and the right rear end push-out portion 120 which engage with the sheet rear end edge of the substantially cylindrical shape in the discharge direction are formed in a comb-teeth shape so as to overlap each other, and as shown in FIG. The right rear end push-out portion 120 formed integrally with the right shift plate 116 from the end side of the left shift plate 114 is shown.

Next, a state in which the substantially flat sheet of FIG. 10 is folded and ejected will be described with reference to FIG. As described above, the substantially flat sheet having a substantially flat shape positioned between the left folding roller 132 and the right folding roller 136 is connected to the left folding roller 132 and the right folding roller 136 by the folding roller separation / contact motor. 178 is driven to move to the roller pressure contact position SC of FIG. 10, and a pressure contact force for folding is applied by the mechanism of the intermediate gear described in FIG. Thereafter, the left folding roller 132 and the right folding roller 136 are rotationally driven by the folding roller drive motor 176 to fold and eject the substantially flat sheet. This state is shown in FIG. 11 by a left-handed folded sheet FP (L) indicated by a two-dot chain line.
By the pressure contact rotation of the left folding roller 132 and the right folding roller 136, at the stage of discharging while performing the folding processing, the left link portion 110 and the right link portion 112 are restored this time. Then, the shift members (the left shift portion 60, the right shift portion 61) move to the shift plate release position SO, the substantially tubular shape forming portion 57 is returned to the approximately tubular shape, and the next sheet is loaded. The sheet winding direction will be described later with reference to FIG.

[Substantially tubular sheet and folded sheet]
Here, the state of the folded sheet created by the substantially tubular folding section (folding processing section) 50 described above will be described with reference to FIG.
FIG. 12A shows a state in which the sheet is held in a substantially tubular shape as described above with reference to FIGS. 4, 5 and 7, and in this figure, the sheet conveyed by the carry-in roller 51 is in a substantially tubular shape. The forming portion 57 is conveyed while rotating and is formed into a substantially tubular shape in which parts thereof are overlapped with each other. A left-handed folded sheet CP (L) is formed on this sheet. When the folding process is performed in the superposed state, a generally known inner tri-fold is obtained.
FIG. 12B is an explanatory diagram showing a state in which the left folding roller 132 and the right folding roller 136 shown in FIG. FIG. 12A shows a left-handed folded sheet FP (L) obtained by making the substantially cylindrical left-handed substantially tubular sheet CP (L) shown in FIG. 12A into a substantially flat shape and then folding the sheet.

It should be noted that, again, the “substantially tubular shape” in the present invention means the approximately tubular shape of the shape shown in FIG. 12 (a), and the “substantially flat shape” is shown in FIGS. 12 (a) and 12 ( A sheet having a shape of an elliptical cross section which is an intermediate shape to that of b) is pressed from both sides of a substantially cylindrical sheet and has a narrower width in the lateral direction and a narrower interval than the substantially cylindrical shape extending in the vertical direction. . The meaning of this intermediate shape is that the diameter is made narrower than the substantially cylindrical shape, and the narrowed sheet having the substantially cylindrical shape is formed between the left folding roller 132 and the right folding roller 136 folding roller located at the roller separating position RR. Allowing the intrusion is enough.

[Folded sheet storage tray]
Next, a state in which a folded sheet discharged from the folding unit 31 while being folded by the left folding roller 132 and the right folding roller 136 will be described with reference to FIG. As shown in the figure, a folded sheet outlet 145 is provided in the frame of the folding unit 31 on the folded sheet discharge side. The folding sheet outlet 145 is provided with a folding unit cover 147 that moves to a position that covers the frame of the folding unit 31 and covers the frame and the release position illustrated.
The folding unit cover 147 is provided with a frame attachment portion 147a attached to the frame of the folding unit 31 and a frame side rotation shaft 147b for rotationally supporting the frame attachment portion 147a, as shown in an enlarged view of a two-dot chain line. There is. A release spring 147c, which constantly biases the folding unit cover 147 in the releasing direction, is laid on the rotation shaft 147b between a frame-side stopper 147d of the folding unit 31 and a stopper pin 147f of the folding unit cover 147. . This structure is the same for the opposite image of the folding unit 31.
Further, the folding unit cover 147 has a surface facing the folded sheet outlet 145 serving as a folded sheet tray portion 148 for storing a folded sheet discharged from the folded sheet outlet 145. Therefore, even if a separate discharge tray is not provided, as shown in FIG. 13, the folded unit cover 147 is stored by being dropped by its own weight onto the folded sheet tray portion 148 on the back surface side.

Further, the folding unit cover 147 on the opposite side of the frame mounting portion 147a is provided with a locking claw 147e that enters the locking hole 149 on the frame side. The locking claw 147e is locked when the folding unit 31 is not used by a locking mechanism that is moved by a solenoid (not shown) provided in the locking hole 149.
Therefore, when the folding control unit 211 (control unit), which will be described later, is configured to operate the locking mechanism to release the lock and release the folding unit cover 147, the folding unit 31 operates. It functions as a display and a folded sheet tray for added convenience.

Further, the locking hole 149 is provided with a folding unit cover sensor Sen3 for detecting the locking claw 147e of the folding unit cover 147. The spear unit cover sensor Sen3 detects the locking claw 147e as a detection flag, and when the locking claw 147e is detected when the folding unit 31 is instructed to operate, the lock mechanism is released.
On the other hand, as another case, when the user releases the folding unit cover 147, the folding control unit 211 (control unit) determines that there is an instruction to execute the folding process, and the substantially cylindrical shape shown in FIGS. If the switching flapper solenoid 172 is operated so as to guide the sheet to the folding section 50 and the switching flapper 49 is made to enter the folding conveyance path 43, the folding processing is executed by releasing the folding unit cover 147. You can also

[Switching of winding direction of substantially tubular shape forming portion 57]
Next, switching of the winding direction of the substantially tubular shape forming portion 57 of the sheet that is approximately tubular at the approximately tubular folding portion 50 will be described with reference to FIGS. 14 to 17. By switching the winding direction, it becomes more convenient by simply changing which of the front and back sides of the folded sheet is used as the cover sheet of the folded sheet.
FIG. 14 is an explanatory view of a cross section of the substantially tubular shape forming portion 57 in which the sheet is wound in the direction opposite to that of FIG. Here, for convenience of description, differences from FIG. 5 are mainly described, and other points are omitted from FIG.
In FIG. 5, the sheet conveyed by the carry-in roller 51 is guided by the first gate 53 to the substantially tubular shape forming portion 57 as a guide gate. Therefore, the sheet is shown as a counterclockwise left-handed substantially cylindrical sheet CP (L).

On the other hand, in the case of FIG. 14, the second gate 55 provided at a position facing the first gate 53 is wound around the substantially tubular shape forming portion 57. As a result, the conveyed sheet becomes a right-handed substantially cylindrical sheet CP (R) in the substantially cylindrical shape forming portion 57, which is the same as the clockwise direction, as shown in FIG.
The difference is that, as shown in FIG. 16, it is possible to select whether the front and back surfaces on which an image is formed are the front and back surfaces of the folded sheet. The image forming apparatus A shown in FIG. 1 or 2 discharges the sheet with the front side facing down, and delivers the sheet to the sheet processing apparatus B including the subsequent folding unit 31 and the binding unit 32. As a result, in FIG. 16 as well, the sheets from the carry-in roller 51 are carried in in the same front / back order. In the present invention, this is guided by either the first gate 53 or the second gate 55 located between the carry-in roller 51 and the substantially tubular folded portion 50 (substantially tubular shaped portion 57), thereby providing a substantially tubular shape. The fact that the direction in which the sheet is wound around the shape forming portion 57 is changed is used.

First, in FIG. 16A, the first gate 53 shown in FIG. 5 guides and conveys the sheet to the substantially tubular shape forming portion 57. According to this, a counterclockwise left-handed substantially cylindrical sheet CP (L) is created. According to this, the sheet is wound with the surface for image formation inside, and when the sheet is a folded sheet, a left-handed folded sheet FP (L) is created as shown in FIG. This folded sheet has three inner folds, and a fold line FL is shown.
On the other hand, in FIG. 16B, the sheet is guided by the second gate 55 shown in FIG. 14 to the substantially tubular shape forming portion 57. According to this, conversely, the clockwise right-handed substantially cylindrical sheet CP (R) is created. According to this, the sheet is wound with the surface on which the image is formed facing outward, and in the case of a folded sheet, a right-handed folded sheet FP (R) is created as shown in FIG. This folded sheet also has three inner folds, and the fold line FL is also shown.

In this way, the front side of the folded sheet can be selected by selecting the first gate 53 or the second gate 55 as the guide gate that determines the winding direction of the substantially tubular shape forming portion 57.
In the above description, the image forming apparatus A shows an example in which the image forming surface is discharged downward, but conversely, an apparatus which discharges the image forming surface upward is also applicable. In short, the front and back can be switched by selecting the winding direction around the substantially tubular shape forming portion 57.

[Switching mechanism for guide gate (first gate 53, second gate 55)]
Here, the guide gate switching mechanism that switches the winding direction of the substantially tubular shape folding portion 50 around the approximately tubular shape forming portion 57 described above will be described with reference back to FIG.
As shown in this figure, the first gate 53 and the second gate 55 are unitized and supported by the guide gate unit 150. As described above, the first gate 53 and the second gate 55 are located between the carry-in roller 51 and the substantially tubular shape forming portion 57 (not shown), and from the direction intersecting the carrying direction of the carry-in roller 51. Either is moving forward or backward.

This selective advance / retreat has the following structure. First, the first gate 53 is supported by the first gate mounting portion 154 of the gate support plate 157 by the first gate support shaft 153 composed of a square shaft. First, the second gate 55 is supported by the second gate mounting portion 156 of the gate support plate 157 by the second gate support shaft 155 which is a square shaft. Therefore, the first gate 53 and the second gate 55 are attached to the same gate support plate 157.

A support plate rack 166 is integrally attached to the lower part of the gate support plate 157, and the support plate rack 166 meshes with a drive motor pinion 164 via a drive shaft 162 of the gate switching motor 160. The gate switching motor 160 is a motor that is attached to the rear frame of the folding unit 31 and can be driven in the forward and reverse directions, and rotates the gate support plate 157 to move the first gate 53 inward.
Also, the other rotation of the gate switching motor 160 can move the gate support plate 157 in the opposite direction to the above to retract the first gate 53 and allow the second gate 55 to enter. Although not particularly shown, the two movement guide holes provided in the gate support plate 157 are engaged with pins protruding from the rear side frame of the folding unit 31 to guide the gate support plate in the horizontal direction in the drawing. It is like this.
The reason why both the first gate 53 and the second gate 55 are cantilevered as shown in the figure is to prevent obstruction of ejection of the folded sheet. In this way, the first gate 53 and the second gate 55 are supported by the gate support plate 157 arranged on the rear side of the folding unit 31 and configured as the guide gate unit 150, which facilitates switching.

[Description of control configuration]
A system control configuration of the image forming apparatus A including the sheet processing apparatus B including the folding unit 31 as the sheet folding apparatus described above will be described with reference to the block diagram of FIG. The image forming apparatus system shown in FIGS. 1 and 2 includes a sheet processing control unit 205 of a sheet processing apparatus B including an image formation control unit 200 of the image forming apparatus A, a guide unit 30, a folding unit 31, a binding unit 32, and a tray unit 33. (Control CPU). The image forming control unit 200 includes a paper feed control unit 202 and an input unit 203. Then, a sheet processing mode such as a "print mode", a "sheet folding mode (including folded sheet surface setting)" and a "sheet binding mode", which will be described later, is set from the control panel 204 provided in the input unit 203.

  The sheet processing control unit 205 is a control CPU that operates the sheet processing apparatus B according to the designated sheet processing mode described above. The sheet processing control unit 205 includes a ROM 206 that stores an operation program and a RAM 207 that stores control data. Further, in the sheet processing control unit 205, for example, in the folding unit 31 according to the present invention, a sheet carry-in sensor Sen1 that detects a sheet conveyed near the entrance roller 45, and a discharge of the folded sheet near the folded sheet exit 145 are detected. A folded sheet carry-out sensor Sen2, a folding unit cover sensor Sen3 that detects whether or not the folding unit cover 147 is released, and a paper surface level sensor that detects a paper surface level to detect the amount of sheets stacked on the stacking tray 90. Signals from the various sensor input units 208 are input.

    Next, the sheet processing control unit 205 includes a sheet conveyance control unit 210 that controls the sheet conveyance of each of the guide unit 30, the folding unit 31, the binding unit 32, and the tray unit 33. Further, the sheet processing control unit 205 controls the folding control unit 211 that performs sheet folding processing in the folding unit 31, the alignment plate 84 that is placed on the processing tray 76 to perform binding in the binding unit 32, and the like. A controller 212 and a stapler controller 213 that controls the stapler 80 that performs the binding process on the sheet bundle placed on the processing tray 76 are provided.

  In particular, the folding control unit 211 (control unit) for controlling the folding unit 31 according to the present invention uses either the first gate 53 or the second gate 55, which is a guide gate, to form the substantially tubular shape forming portion 57 of the approximately tubular shape folding portion 50. The gate switching motor 160 for selectively moving the gate support plate is controlled to determine the winding direction depending on whether the guide is guided to. Further, the folding control unit 211 (control unit) guides the sheet from the folding drive path 170 to the folding introduction path 108 by the conveyance drive motor 170 that drives the entrance roller 45, the exit roller 47, and the carry-in roller 51, and guides the sheet to the carry-in roller 51. The switching flapper solenoid 172 that moves the switching flapper 49 that selects whether or not to control is controlled. Further, the folding control section 211 (control section) shifts the substantially tubular shape forming portion 57 of the approximately tubular folding section 50 to shift the approximately tubular shape to a substantially flat shape by shifting members (left shift section 60, right shift). (Shift plate) moving motor 174 for moving the portion 61) and the folding roller separating the folding rollers (the left folding roller 132 and the right folding roller 136) to separate or press in order to further fold the substantially flat sheet. The contact motor 178 and the folding roller drive motor 176 that drives and rotates this folding roller are controlled.

Although not shown in FIG. 18, the folding control unit 211 (control unit) controls the folding unit cover 147 described in FIG. 13 so as to release the folding unit cover 147 by operating the lock mechanism with a solenoid or the like. In this case, the operation of the folding unit 31 is displayed and the folding sheet tray functions as a folding sheet tray, which improves convenience.
Further, when the unit cover sensor Sen3 detects the engaging claw 197e when the folding unit 31 is instructed to operate, the lock mechanism may be released.

Further, as control in other cases, when the user releases the folding unit cover 147, it is determined that the unit cover sensor Sen3 disengages the engaging claw 197e and thus the folding control unit 211 (the folding control unit 211 is instructed to perform the folding process. The control section) makes a judgment and operates the switching flapper solenoid 172 so as to guide the sheet to the substantially tubular folding section 50 shown in FIG. 3 and FIG. 5 so that the switching flapper 49 enters the folding conveyance path 43. As described above, the folding process can be executed by releasing the folding unit cover 147, as described above.
The sheet processing control unit 205 also includes a stacking tray raising / lowering control unit 214 that controls the raising / lowering motor 95 based on a detection signal from the paper surface level sensor for raising / lowering the stacking tray 90.

[Sheet processing mode]
The sheet processing control unit 205 of the present embodiment configured as described above causes the sheet processing apparatus B to execute, for example, a “print mode”, a “sheet folding mode (including folded sheet surface setting)”, a “sheet binding mode”, or the like. . Hereinafter, this processing mode will be described.
(1) "Printout mode"
The sheet on which the image is formed is received from the main body discharge port 16 of the image forming apparatus A, and the sheets are accommodated one by one in the stacking tray 90 by the bundle discharge roller 86 via the binding carry-in roller 72 and the carry-out roller 74.
(2) "Sheet folding mode"
The sheet from the conveying path 37 of the guide unit 30 is conveyed to the substantially tubular folding portion of the folding unit 31 to perform simple sheet folding, and the folded sheet is discharged to the front side of the apparatus intersecting the sheet conveying direction of the conveying path 37. To do.
In addition to this sheet folding mode setting, which side of the image-formed sheet shown in FIG. 16 is set as the front side of the folded sheet is set. When there is no setting, the state of FIG. 16A is set as the initial setting.
(3) "Sheet binding mode"
The sheet on which the image is formed from the main body discharge port 16 is temporarily placed on the processing tray 76 of the binding unit 32 into a bundle through the guide unit 30 and the folding unit 31, and the bundle is bound by the stapler 80. The sheets are collected on the collecting tray 90.

According to the embodiment for carrying out the invention described above, the following effects are obtained.
1. A sheet folding device (folding unit 31) for folding sheets, including a holding member (substantially tubular shape forming portion 57) that holds a conveyed sheet in a substantially tubular shape, and a substantially tubular shape held by the holding member. A shift member (left shift portion 60, right shift portion 61) that presses the outer peripheral surface of the shaped sheet to form a substantially flat shape, and further presses the sheet that has become a substantially flat shape by the shift members, and the direction of the outer peripheral edge of the sheet The sheet folding device includes a sheet discharging unit (left folding roller 132, right folding roller 136) that discharges the sheet.
According to this, a folding mechanism that holds a sheet in a substantially cylindrical shape and ejects the sheet while pressing the sheet into a substantially flat shape performs folding processing without using a conveyance path along the sheet length or three folding rollers in pressure contact. It is possible to provide a relatively compact sheet folding device capable of performing the above.

2. The above-mentioned holding member (substantially tubular shape forming portion 57) is the sheet folding apparatus described in 1 above, which is made of a deformable sheet material.
According to this, a reliable substantially cylindrical sheet can be formed by the sheet member.

3. The holding member (substantially tubular shape forming portion 57) is composed of an outer guide (outer guide 57a) for guiding the outer side of the conveyed sheet and an inner guide (inner guide 57b) for guiding the inner side. 2 is a sheet folding apparatus.
According to this, since the guided sheet is guided on both sides, a substantially tubular sheet can be formed more reliably.

4. The sheet folding apparatus according to the above item 2, wherein the shift members (the left shift portion 60 and the right shift portion 61) are flat plate pressing members that press the outer peripheral surface of the substantially cylindrical sheet.
According to this, since the shift portion is composed of the flat plate pressing member extending in the sheet width direction, the substantially tubular sheet can be reliably deformed into the substantially flat shape.

5. The sheet folding according to 4, wherein the shift members (the left shift portion 60 and the right shift portion 61) are pressed from the direction in which the outer peripheral surface of the substantially cylindrical sheet is sandwiched and are also moved to the discharge portion side. There is a device.
According to this, the substantially cylindrical sheet can be deformed into a substantially flat shape and moved to the discharge side at the same time.

6. The sheet folding device according to the above 5, wherein the discharging unit includes discharging rollers (a left folding roller 132 and a right folding roller 136) provided on one edge of the outer peripheral surface of the sheet.
According to this, since the folded sheet is discharged to the discharge side of the end portion of the outer peripheral surface of the sheet (the end portion in the direction intersecting with the sheet winding), it can be confirmed that the folding processing operation is performed.

7. The discharge rollers (the left folding roller 132 and the right folding roller 136) are provided as a pair so as to be separable from each other, and the shift member (the left shift portion 60, the right shift portion 61) makes the substantially cylindrical sheet substantially flat. 7. The sheet folding apparatus according to the above 6, wherein the sheet is folded between the ejecting rollers separated from each other, and then the ejecting rollers are pressed and rotated to fold the sheet.
According to this, the flattened sheet is discharged while being further folded, so that a folded sheet with a firm crease can be created.

8. A sheet folding device (folding unit 31) for folding sheets, including a transport roller (transport roller 51) for transporting the sheet, and a deformable container that holds the sheet transported by the transport roller in a substantially tubular shape. A holding member (substantially tubular shape forming portion 57) made of a flexible sheet and the outer peripheral surface of the sheet held by the holding member in the first tubular state are pressed into a second substantially flat state. A shift member (left shift portion 60, right shift portion 61) that shifts, and a discharge roller (at the outer peripheral edge of the detachable sheet that presses and conveys the sheet in the second state by the shift member) ( The sheet folding device includes a left folding roller 132 and a right folding roller 136).
According to this, a folding mechanism that holds a sheet in a substantially cylindrical shape and ejects the sheet while pressing the sheet into a substantially flat shape performs folding processing without using a conveyance path along the sheet length or three folding rollers in pressure contact. It is possible to provide a relatively compact sheet folding device capable of performing the above.

9. The sheet folding apparatus according to the above 8, wherein the holding member (substantially tubular shape forming portion 57) is set to have a length in which the sheets held in the first state overlap each other.
According to this, an inner tri-folded sheet can also be created depending on the degree of this overlap.

10. The image forming unit 2 for forming an image on a sheet, a sheet folding device (folding unit 31) for folding a sheet from the image forming unit, and the sheet folding device according to any one of 1 to 9 above. The image forming apparatus A is provided with.
According to this, an image forming apparatus having the effects described in the above items can be provided.

11. A reading unit (image reading device 20) for reading an image of a document is provided above the image forming unit 2, and a sheet discharging space is provided between the reading unit and the image forming unit.
The image forming apparatus according to the above 10, wherein the sheet folding device (folding unit 31) is arranged in the sheet discharge space.
According to this, it is possible to provide an image forming apparatus equipped with a sheet folding device that achieves the above-described effects 1 to 9 which is also applicable to a so-called in-body type.

12. A sheet folding method for folding sheets, comprising a holding step of holding a conveyed sheet in a substantially tubular shape, and pressing the outer peripheral surface of the substantially tubular sheet formed in the holding step into a substantially flat shape. And a discharging step of further pressing the sheet that has become substantially flat by the shifting step and discharging the sheet while folding the sheet in a direction intersecting the conveying direction.
According to this, since the sheet folding method in which the sheet is held in a substantially tubular shape is ejected while pressing the sheet into a substantially flat shape, a relatively compact and simple folding method can be provided.

  In the description of the effects of the above-described embodiment, for each part of the present embodiment, the corresponding member of each component in the claims is shown in parentheses, or a reference sign is attached to indicate the relationship between the two. Was made clear.

  Furthermore, the present invention is not limited to the above-described embodiments, and various modifications can be made without departing from the present invention, and all the technical matters included in the technical idea described in the claims are the present invention. It is the subject of the invention. Although the embodiments described above show suitable examples, those skilled in the art can realize various alternatives, modifications, variations, or improvements from the contents disclosed in this specification. Which are within the scope of the appended claims.

A image forming apparatus B sheet processing apparatus 30 guide unit 31 folding unit (sheet folding apparatus)
32 binding unit 33 tray unit 41 folding switchback path 43 folding conveyance path 49 switching flapper 50 substantially tubular folding section (folding processing section)
51 carry-in roller (conveyor roller)
53 First Gate (Information Gate)
55 2nd gate (guide gate)
57 Substantially tubular shape forming part (holding member)
57a Outer guide 57b Inner guide 60 Left shift section 61 Right shift section 80 Stapler (binding processing section)
99 lift rail 100 lift rack 101 extension rail 102 extension rack 104 folding carry-in entrance 106 folding carry-out exit 108 folding introduction path 110 left link part 112 right link part 114 left shift plate (pressing part)
116 Right shift plate (pressing part)
118 Left rear end extruding section 120 Right rear end extruding section 132 Left folding roller (discharge roller / folding roller)
136 Right folding roller (discharge roller / folding roller)
145 Folded sheet exit 147 Folding unit cover 148 Folded sheet tray part 150 Guide gate unit 160 Gate switching motor 170 Conveyance drive motor 174 Proximity separation motor 176 Folding roller drive motor 178 Folding roller separation / contact motor 181 Transmission gear 182 Transmission worm gear 183 Fan gear 199 Intermediate gear 210 Sheet conveyance control unit 211 Folding control unit (control unit)

Claims (12)

A sheet folding device for folding sheets,
Conveying means for conveying the sheet in a predetermined conveying direction intersecting the width direction,
A holding member for holding the sheet conveyed by the conveying means in a substantially tubular shape,
A shift member in an approximately flat shape by pressing in a direction crossing the outer circumferential surface of the substantially cylindrical shape sheet held in the holding member and the width direction of the sheet,
Sheet folding apparatus characterized by comprising a discharge portion for discharging the width direction while pressing further the cross direction of the sheet which becomes substantially flat by the shift member.   2. The sheet folding apparatus according to claim 1, wherein the holding member is made of a deformable sheet material. 3. The sheet folding apparatus according to claim 2, wherein the holding member includes an outer guide that guides the outer side of the sheet conveyed by the conveying unit and an inner guide that guides the inner side.   3. The sheet folding apparatus according to claim 2, wherein the shift member is composed of a flat plate-shaped press member that presses the outer peripheral surface of the substantially cylindrical sheet.   5. The sheet folding apparatus according to claim 4, wherein the shift member pushes the substantially cylindrical sheet from the intersecting direction and also moves the sheet toward the discharge portion.   The sheet folding apparatus according to claim 5, wherein the discharging unit includes a discharging roller provided on one edge of the outer peripheral surface of the sheet. The discharge rollers are provided as a pair so as to be separable from each other, and the substantially cylindrical sheet is made to enter between the separated discharge rollers by the shift member so as to have a substantially flat shape, and then the discharge rollers are rotated by pressing to rotate the sheet. The sheet folding apparatus according to claim 6, wherein the sheet folding apparatus is configured to fold the sheets. A sheet folding device for folding sheets,
A transport roller for transporting the sheet,
A holding member made of a deformable flexible sheet for holding the sheet conveyed by the conveying roller in a substantially tubular shape;
A shift member for shifting the second state substantially flat by pressing the outer peripheral surface of the sheet held in a first state of a substantially cylindrical shape in the holding member,
A sheet folding apparatus, comprising: a folding roller which is provided on one edge of the outer peripheral surface of the sheet and which is capable of pressing and transporting the sheet in the second state by the shift member, and being detachable and contactable.   9. The sheet folding apparatus according to claim 8, wherein the holding member is set to have a length in which the sheets held in the first state overlap each other. An image forming unit that forms an image on a sheet,
A sheet folding device that folds the sheets from the image forming unit,
An image forming apparatus comprising the sheet folding device having the configuration according to claim 1. A reading unit for reading the image of the document above the image forming unit,
A sheet discharge space is provided between the reading unit and the image forming unit,
The image forming apparatus according to claim 10, wherein the sheet folding device is arranged in the sheet discharging space. A sheet folding method for folding sheets,
A holding step of holding a sheet conveyed in a predetermined conveying direction intersecting the width direction in a substantially tubular shape,
A shift step of substantially into a flat shape by pressing the outer peripheral surface of the substantially cylindrical shape sheet formed in the holding step,
A sheet folding method, further comprising: a discharging step of further pressing a sheet that has become substantially flat by the shift step and discharging the sheet while folding the sheet in a direction intersecting the transport direction.

Images