Patent Grant
11560286
This application is based on and claims the benefit of priority from Japanese patent application No. 2020-157040 filed on Sep. 18, 2020, which is incorporated by reference in its entirety.
The present disclosure relates to a sheet folding device performing a folding processing on a sheet, such as a paper sheet, on which an image is formed by an image forming apparatus, such as a copying machine and a printer, and a sheet post-processing apparatus including the sheet folding device.
A sheet post-processing apparatus provided with a sheet folding device which performs a folding processing on a paper sheet (a sheet) on which an image is formed by an image forming apparatus, such as a copying machine and a printer, is conventionally used.
The sheet folding device provided with a folding rollers pair consisting of two folding rollers and a folding blade capable of advancing to and retreating from a nip area between the folding rollers is known. In the sheet folding device, a predetermined portion of the sheet is bent by the folding blade and then pushed into the nip area of the folding rollers. Then, the sheet is pressed at the nip area of the folding rollers, thereby performing a folding processing on the sheet.
For example, the folding blade is pushed into the nip area from a direction opposite to the folding rollers in a state where the center of the sheet is positioned to the nip area when the paper is folded in two and in a state where the ⅓ portion of the sheet is positioned to the nip area when the sheet is folded in three.
As a method for pushing the folding blade, there are a method for reciprocating the folding blade to the sheet and pushing the sheet and a method for rotationally driving the folding blade and pushing the sheet. The method for rotationally rotating the folding blade makes the number of member small and the structure simple.
For example, in a method for folding the sheet using a fixing rollers pair, an image forming apparatus is provided, which includes a first conveyance path for guiding the sheet to the fixing rollers pair, a second conveyance path for guiding the sheet on which a toner image is fixed by the fixing rollers pair to the first conveyance path, a third conveyance which is branched from the first conveyance path between a second transfer area and the fixing rollers pair and guides the sheet to the second conveyance path, and a switching member for switching the sheet conveying destination to the fixing rollers pair or the third conveyance path.
When the sheet is folded, the switching member provided at a branch portion between the first conveyance path and the third conveyance path is rotated, and pushes a loop (a deflected portion) of the sheet into the nip area of the fixing rollers pair, as a folding blade.
However, when the folding blade is rotationally driven as described above, in order to push the folding blade from the side opposite to the folding direction, it is necessary to provide the turning fulcrum of the folding blade on the same side as the folding blade with respect to the sheet. That is, since the turning fulcrum of the folding blade is located on the side opposite to the folding rollers pair with respect to the sheet, it is difficult to make the turning locus of the folding blade perpendicular to the sheet when the sheet is pushed in. Therefore, there is a problem that the sheet cannot be accurately pushed into the nip area of the folding rollers. Further, since the mounting position of the folding blade is largely restricted in relation to the component configuration, it is impossible to make the folding blade large, and there is a problem that it is not possible to push in the sheet sufficiently.
In accordance with an aspect of the present disclosure, a sheet folding device includes a folding rollers pair, a folding blade and a sheet guide. The folding rollers pair is configured to cause a sheet conveyed along a sheet conveyance path extending in a first conveyance direction to pass through a first nip area to fold the sheet in two and to convey the sheet in a first direction crossing to the first conveyance direction. The folding blade extends in an axial direction of the folding rollers pair, is disposed facing the folding rollers pair, and is configured to push a folded portion of the sheet into the first nip area. The sheet guide extends in the axial direction on an upstream side of the folding rollers pair in the first direction. The folding blade includes a pivot shaft, a blade portion and a pair of arm portions. The pivot shaft is provided parallel to the axial direction. The blade portion is pivotable around the pivot shaft, and is selectively disposed in a folding position where the blade portion pushes the folded portion of the sheet into the first nip area and in a retracting position where the blade portion is retracted from the folding position to an opposite side to the folding rollers pair with respect to the sheet conveyance path. The pair of arm portions couples both end portions of the blade portion in the axial direction with the pivot shaft. The sheet guide can be passed between the pair of arm portions. The blade portion faces the sheet guide in a state of being disposed in the retracting position, and forms, between the blade portion and the sheet guide, a retreating path in which a part of the sheet is retreated when the folded portion is pushed into the first nip area.
In accordance with an aspect of the present disclosure, a sheet post-processing apparatus includes a carry-in port into which a sheet is carried; the sheet folding apparatus configured to perform the folding processing on the sheet conveyed from the carry-in port; a discharge port through which the sheet is discharged; and a discharge tray configured to receive the sheet discharged through the discharge port is stacked.
The other features and advantages of the present disclosure will become more apparent from the following description. In the detailed description, reference is made to the accompanying drawings, and preferred embodiments of the present disclosure are shown by way of example in the accompanying drawings.
Hereinafter, with reference to the attached drawings, an embodiment of the present disclosure will be described.
As shown in
The sheet post-processing apparatus 30 is connected to the image forming apparatus 10, and performs a post-processing such as a punching processing, a binding processing and a folding processing, on the sheet conveyed from the image forming apparatus 10. The sheet post-processing apparatus 30 is not limited to that performing the post-processing on the sheet automatically conveyed from the image forming apparatus 10, and may perform the post-processing on the sheet which is placed on a tray (not shown) by a user and then naturally conveyed to a position where the post-processing can be performed.
As shown in
The sheet carry-in port 36 and the main discharge port 37 are communicated with each other by a first conveyance path 42. A second conveyance path 43 branched and connected to the first conveyance path 42 is connected to the sub discharge port 39. A third conveyance path 44 branched and connected to the first conveyance path 42 is connected to the second sheet folding unit 80.
The sheet received through the sheet carry-in port 36 is fed to the downstream side (the left side in
At the downstream end of the second conveyance path 43, a sub discharge rollers pair 48 which feeds the sheet to the sub discharge tray 40 is provided. The sub discharge tray 40 mainly receives the sheet discharged without being subjected to the post-processing by the post-processing apparatus 30, the sheet to which only to the punching processing is performed by the punching unit 33, and the sheet to which only the folding processing is performed by the first sheet folding unit 60.
The punching unit 33 is disposed between the sheet carry-in port 36 and the first sheet folding unit 60 above the first conveyance path 42. The punching unit 33 performs the punching processing on the sheet conveyed on the first conveyance path 42 at a predetermined timing.
The staple unit 35 is disposed below the downstream side portion of the first conveyance path 42. The staple unit 35 performs a stacking processing for stacking a plurality of the sheets to form a sheet bundle, and performs the binding processing for stapling the sheet bundle with a staple.
The first sheet folding unit 60 is disposed immediately upstream of a branching portion of the first conveyance path 42 and the second conveyance path 43. The first sheet folding unit 60 performs the folding processing on the sheet, for example, when the user selects the folding processing for one sheet. The detailed configuration of the first sheet folding unit 60 will be described later.
The second sheet folding unit 80 is disposed in the lower portion of the sheet post-processing apparatus 30 on the downstream side portion of the third conveyance path 44. The second sheet folding unit 80 performs the folding processing on the sheet bundle consisting of a plurality of the sheets, for example, when the user selects the folding processing on the sheet bundle. On the downstream side of the second sheet folding unit 80, a lower discharge port 85 through which the sheet bundle folded by the second sheet folding unit 80 is discharged and a lower discharge tray 87 on which the sheet bundle discharged through the lower discharge port 85 is received are provided.
The folding rollers pair 64 consists of a first roller 63a and a second roller 63b. The second roller 63b is brought into pressure contact with the first roller 63a at a predetermined pressure by a first pressure contact mechanism 70 to form a first nip area N1. The sheet S passed through the first nip area N1 is conveyed from the right to the left (a first direction X1) in
The first conveyance rollers pair 65 consists of the first roller 63a and a third roller 63c. The third roller 63c is brought into pressure contact with the first roller 63a at a predetermined pressure by a second pressure contact mechanism 71 to form a second nip area N2. The sheet S passed through the second nip area N2 is conveyed along a conveyance path 74 extending in a direction (a first conveyance direction X2) from the upper to the lower in
The second roller 63b is brought into pressure contact with the first roller 63a on the downstream side (the lower side in
A fourth roller 63d is brought into pressure contact with the third roller 63c to constitute a second conveyance rollers pair 66. The fourth roller 63d consists of two roller parts divided in the axial direction (a direction perpendicular to the paper plane on which
The folding blade 67 has a pivot shaft 67a, a blade portion 67b and arm portions 67c. The pivot shaft 67a is provided on the same side (the left side in FIG. 4) as the folding rollers pair 64 with respect to the conveyance path 74 for the sheet S parallel to axes of the folding rollers pair 64, and is supported by a first frame 93a of the sheet post-processing apparatus 93 in a turnable manner. The blade portion 67b is disposed on the opposite side (the right side in
The fixed guide 68 and the movable guide 69 are disposed on the conveyance path 74 for the sheet S passed the second nip area N2 on the upstream side of the folding rollers pair 64 in the first direction X1, and guides the sheet S passed through the second nip area N2. The fixed guide 68 is fixed between the first conveyance rollers pair 65 and the folding blade 67. The movable guide 69 is disposed between the pivot shaft 67a and the blade portion 67b of the folding blade 67, and forms the retreating path 73 together with the inner surface of the blade portion 67b. The movable guide 69 can reciprocate between a covering position (see
Next, with reference to
First, a case where the sheet S is folded in two will be described. As shown in
A timing when the conveyance of the sheet S is stopped is determined based on a detection timing of a sheet detection sensor 75 (see
Next, as shown in
The sheet S formed with the fold line F is conveyed on the second conveyance path 43, and then discharged through the sub discharge port 39 (the sub discharge rollers pair 48) on the sub discharge tray 40. Thereafter, the movable guide 69 is shifted to the covering position and the folding blade 67 is shifted to the retracting position, that is, they are returned to the state shown in
Next, a case where the sheet S is folded in three (a Z-shaped folding) will be described. In the processing for folding the sheet S in three, first, the switching guide 72 (see
Next, the switching guide 72 is shifted downward. At this time, the switching guide 72 comes into contact with the sheet S at the first portion to be folded. The sheet S pushed out by the switching guide 72 is pushed into the second nip area N2 of the first conveyance rollers pair 65 in a bent state as shown in
Thereafter, the sheet S is passed through the second nip area N2 with the first fold line F1 forward, is conveyed in the conveyance path 74, is passed between the fixed guide 68 and the movable guide 69, and then enters the retreating path 73. Then, the conveyance of the sheet S is stopped such that the second portion to be folded (the portion apart from the leading edge of the sheet S by ⅔ of the length of the sheet S) faces the first nip area N1. A timing when the conveyance of the sheet S is stopped is determined based on the detection timing of the sheet detection sensor 75.
Next, as shown in
The sheet S formed with the first fold line F1 and the second fold line F2 is conveyed along the second conveyance path 43 and then discharged through the sub discharge port 39 (the sub discharge rollers pair 48) on the sub discharge tray 40. Thereafter, the movable guide 69 is shifted to the covering position and the folding blade 67 is shifted to the retracting position, and the switching guide 72 is retreated upward. After that, the processing for folding the sheet S in three is performed in the same manner.
The drive mechanism 90 includes the drive input gear 76, a first gear 67c, a link member 78 and a drive motor 91 (see
The link member 78 has a base part 78a, a rotational shaft 78b formed on one end portion of the base part 78a, an engagement boss 78c formed on the other end portion of the base part 78a, and a second gear 78d formed on the outer circumferential surface of the rotational shaft 78b. The link member 78 is supported to the second frame 93b by the rotational shaft 78b in a rotatable manner. The engagement boss 78c is engaged with the engaged portion 69a of the movable guide 69. The second gear 78d is meshed with the first gear 67c.
When the drive input gear 76 is rotated by a predetermined angle in the clockwise direction (a forward direction) from a state shown in
In addition, the first gear 67c formed on the pivot shaft 67a is rotated in the clockwise direction, and the second gear 78d meshed with the first gear 67c is rotated in the counterclockwise direction. Thus, the link member 78 is rotated in the counterclockwise direction around the rotational shaft 78b, and the movable guide 69 engaged with the link member 78 is shifted downward to be disposed in the non-covering position shown in
On the other hand, when the drive input gear 76 is rotated by a predetermined angle in the counterclockwise direction (a reverse direction) from a state shown in
In addition, the first gear 67c formed on the pivot shaft 67a is rotated in the counterclockwise direction, and the second gear 78d meshed with the first gear 67c is rotated in the clockwise direction. Thus, the link member 78 is rotated in the clockwise direction around the rotational shaft 78b, the movable guide 69 engaged with the link member 78 is shifted upward to be disposed in the covering position shown in
According to the configuration of the present embodiment, the pivot shaft 67a of the folding blade 67 is disposed on the same side as the folding rollers pair 64 with respect to the sheet S to be folded (the conveyance path 74). In other words, the sheet which passes through the second nip area N2, is conveyed to the conveyance path 74 and is to be folded by the folding roller pair 64 stops at a position facing the folding rollers pair 64, and the pivot shaft 67a is disposed on the same side as the folding rollers pair 64 with respect to the sheet S. Then, when the sheet S is pushed into the first nip area N1 by the blade portion 67b, it becomes possible to make the moving locus of the blade portion 67b substantially perpendicular to the sheet S, so that the sheet S can be pushed into the first nip area N1 with higher accuracy.
In addition, when the folding blade 67 is disposed in the retracting position, the retreating path 73 is formed between the pivot shaft 67a and the blade portion 67b of the folding blade 67. Then, even if the pivot shaft 67a and the blade portion 67b of the folding blade 67 are disposed on opposite sides to each other with respect to the sheet S, it becomes possible to ensure the retreating path 73 of the sheet S, so that a degree of freedom in arrangement of the folding blade 67 can be enhanced.
In the present embodiment, the movable guide 69 movable between the covering position where it covers the outer circumferential surface of the second roller 63b of the folding rollers pair 64 and the non-covering position where it exposes the outer circumferential surface of the second roller 63b is provided. Thus, when the sheet S enters the retreating path 73 before the folding processing, the movable guide 69 is disposed in the covering position, so that the sheet S is prevented from coming into contact with the second roller 63b of the folding rollers pair 64 rotating in a reverse direction to the conveyance direction, and it becomes possible to prevent the jamming of the sheet S and the edge folding of the sheet S. Then, when the folding processing is performed, the movable guide 69 is disposed in the non-covering position, so that the sheet S can be pushed into the first nip area N1 smoothly by the folding blade 67.
In addition, by driving the folding blade 67 and the movable guide 69 using the drive mechanism 90 including one drive motor 91, the movable guide 69 is shifted to the non-covering position with the movement of the folding blade 67 to the folding position, and the movable guide 69 is moved to the covering position with the movement of the folding blade 67 to the retracting position. Therefore, it is not necessary to synchronize the movement timing of the folding blade 67 with the movement timing of the movable guide 69, and the control mechanism by the post-processing controller 101 can be made simple. In addition, the number of motors can be reduced, thereby contributing to cost reduction.
Further, the first roller 63a constitutes the folding rollers pair 64 together with the second roller 63b, and constitutes the first conveyance rollers pair 65 together with the third roller 63c, so that the first rollers 63a also serve as the folding rollers pair 64 and the first conveyance rollers pair 65. Thus, the number of rollers and the arrangement space can be reduced.
In addition, the present disclosure is not limited to the above embodiments, and various modifications can be made without departing from the spirit of the present disclosure. For example, in the embodiment described above, the first sheet folding unit 60 includes the folding rollers pair 64 and the first conveyance rollers pair 65 each consisting of two of the three rollers of the first roller 63a to the third roller 63c, but the present disclosure is not limited thereto, and for example, as shown in
In the above embodiment, the first gear 67c is formed on the pivot shaft 67a of the folding blade 67, and the second gear 78d is formed on the rotational shaft 78b of the link member 78 to directly connect the folding blade 67 and the link member 78, but one or more gears may be disposed between the folding blade 67 and the link member 78 and connect them.
Further, in the above embodiment, the multifunctional peripheral as shown in
| Number | Date | Country | Kind |
|---|---|---|---|
| JP2020-157040 | Sep 2020 | JP | national |
| Number | Name | Date | Kind |
|---|---|---|---|
| 4985013 | van der Werff | Jan 1991 | A |
| 6565076 | Kubota | May 2003 | B2 |
| 6881181 | Brown | Apr 2005 | B2 |
| 8257238 | Eijkelkamp | Sep 2012 | B2 |
| 10599088 | Matsuno | Mar 2020 | B2 |
| 11225391 | Fukasawa | Jan 2022 | B2 |
| 20100133736 | Park | Jun 2010 | A1 |
| Number | Date | Country |
|---|---|---|
| 2017-132572 | Aug 2017 | JP |
| Number | Date | Country | |
|---|---|---|---|
| 20220089402 A1 | Mar 2022 | US |
