JP5928119B2 - Post-processing apparatus and image forming apparatus - Google Patents

Description

  The present invention relates to a post-processing apparatus that performs post-processing on paper discharged from the image forming apparatus main body, and an image forming apparatus such as a copying machine, a printer, a facsimile, or a multifunction peripheral including the post-processing apparatus. The present invention relates to a post-processing apparatus capable of performing a punching process on a sheet and an image forming apparatus.

Conventionally, as a post-processing device installed in an image forming apparatus such as a copying machine or a printer, a punching unit (punching unit) that performs punching processing and a stapling process that performs stapling processing in a paper discharge unit of the main body of the image forming apparatus There are known ones in which the sections (staple units) are arranged in parallel in the paper discharge direction (see, for example, Patent Document 1).
In such a post-processing apparatus, punching processing by the punch processing unit and stapling processing by the stapling processing unit are performed on the front side (or the rear end side) of the paper discharged from the image forming apparatus main body. Will be.

  In Patent Document 2, the post-processing device is installed in the space of the paper discharge unit formed between the upper image reading unit and the lower image forming unit for the purpose of compactly installing the post-processing device. Techniques to do this are disclosed.

In the conventional post-processing apparatus, a punch processing unit or the like is installed on the front end side (or rear end side) in the discharge direction with respect to the paper discharged from the image forming apparatus main body. It was.
In order to solve such a problem, a punch processing unit or the like is installed on one end side in the width direction orthogonal to the discharge direction with respect to the paper discharged from the image forming apparatus main body, and the punch is formed on one end side in the width direction of the paper. It is conceivable to configure such that post-processing such as processing is performed. However, the paper discharged from the image forming apparatus main body may be undulated in the discharge direction due to the heat received during the fixing process and the load received during conveyance in the apparatus main body. If the perforated process is directly performed on the one end in the width direction of the sheet in the state in which it is in a state, a distorted punch hole is formed or the punch hole is displaced from the target position.

  The present invention has been made to solve the above-described problems. Even when the paper discharged from the image forming apparatus main body undulates in the discharge direction, the accuracy of the paper is reduced toward one end in the width direction of the paper. An object of the present invention is to provide a post-processing apparatus and an image forming apparatus that can perform high perforation processing.

  A post-processing apparatus according to a first aspect of the present invention is a post-processing apparatus that performs post-processing on a sheet discharged from an image forming apparatus body, and a discharge direction of the sheet discharged from the image forming apparatus body 2 is formed so that one end in the width direction of the paper discharged from the image forming apparatus main body can be gripped at two positions apart in the discharge direction. At least one of the two gripping portions is moved in the discharge direction so as to widen the gripping direction and the gripping direction of the paper gripped at a position separated in the discharge direction. A moving means for moving in the direction along the direction of the paper, and the width of the paper gripped by the two gripping sections in a state where the interval in the discharge direction is widened by the movement of the gripping section by the moving means A punching unit for performing punching in a position between said a one end side two gripping portions are those having a.

  In the present invention, at least one of the two gripping portions is disposed in the discharge direction so as to widen the gap in the gripped discharge direction for the paper gripped at two positions separated in the discharge direction. And punching processing by the punch processing unit is performed on the paper gripped by the two gripping units in this state. Thereby, even when the paper discharged from the image forming apparatus main body undulates in the discharge direction, the post-processing device and the image forming are performed with high-precision punching processing on one end side in the width direction of the paper An apparatus can be provided.

1 is an overall configuration diagram illustrating an image forming apparatus according to an embodiment of the present invention. FIG. 6 is a schematic top view illustrating the operation of a sheet in the post-processing apparatus. It is the schematic which shows the post-processing apparatus seen from the XX cross section of FIG. It is a schematic top view which shows the post-processing apparatus of FIG. It is a side view which shows operation | movement of a clamp unit. It is a top view which shows operation | movement of two holding parts. (A) Schematic diagram showing a state in which a punching process is performed on paper in a wavy state, and (B) a schematic diagram showing punch holes formed at that time. It is a top view which shows operation | movement of two holding parts in the post-processing apparatus of the 1st modification. It is a top view which shows operation | movement of two holding parts in the post-processing apparatus of the 2nd modification.

Embodiment.
Hereinafter, embodiments for carrying out the present invention will be described in detail with reference to the drawings. In addition, in each figure, the same code | symbol is attached | subjected to the part which is the same or it corresponds, The duplication description is simplified or abbreviate | omitted suitably.

First, the configuration and operation of the entire image forming apparatus will be described with reference to FIG.
The image forming apparatus 1 according to the present embodiment is a tandem type color image forming apparatus in which a plurality of process cartridges 10Y, 10M, 10C, and 10BK are arranged in parallel so as to face the intermediate transfer belt 17.

  In FIG. 1, reference numeral 1 denotes an apparatus main body of a color copying machine as an image forming apparatus, 3 an original conveying unit that conveys an original to an image reading unit 4, and 4 an image reading unit (original reading unit) that reads image information of the original. Reference numeral 6 denotes a writing unit (exposure unit) that emits laser light based on input image information, 7 denotes a paper feeding unit (paper feeding cassette) that stores paper P such as transfer paper, and 10Y, 10M, 10C, and 10BK each color ( A process cartridge as an image forming unit corresponding to yellow, magenta, cyan, and black), 17 is an intermediate transfer belt (intermediate transfer body) on which toner images of a plurality of colors are transferred, and 18 is formed on the intermediate transfer belt 17 Secondary transfer roller for transferring the toner image to the paper P (recording medium), 20 for fixing the unfixed image on the paper P, and 28 for each process cartridge 10Y, 10M, 10C, 10B. The toner container for supplying toner of each color to the developing device, 30 denotes a post-processing apparatus.

Here, in the image forming apparatus according to the present embodiment, the paper discharge unit from which the paper P is discharged from the apparatus main body 1 is a part in which a main part that performs image formation such as an image forming unit is provided. .) And the image reading unit 4. That is, the paper P on which a desired image is formed on the surface is discharged as an output image into the space between the image forming unit and the image reading unit 4. In the paper discharge unit, a post-processing device 30 for performing punching processing and binding processing on the discharged paper P is detachably installed. In other words, the image reading unit 4 is installed so as to sandwich the post-processing device 30 at a position above the paper discharge unit. As described above, by using the space between the image forming unit and the image reading unit 4 and installing the post-processing device 30 in the space, the entire image forming device can be downsized (compact). .
Each process cartridge 10Y, 10M, 10C, 10BK (image forming unit) is a unit in which a photosensitive drum 11 as an image carrier, a charging unit, a developing unit (developing device), and cleaning are integrated. . A toner image of each color (yellow, magenta, cyan, black) is formed on the photosensitive drum 11 (image carrier) in each of the process cartridges 10Y, 10M, 10C, and 10BK.

Hereinafter, an operation during normal color image formation in the image forming apparatus will be described.
First, the document is transported from the document table by the transport rollers of the document transport unit 3 and placed on the contact glass of the image reading unit 4. Then, the image reading unit 4 optically reads the image information of the document placed on the contact glass.
Specifically, the image reading unit 4 scans an image of a document on the contact glass while irradiating light emitted from an illumination lamp. Then, the light reflected from the original is imaged on the color sensor via the mirror group and the lens. The color image information of the original is read for each color separation light of RGB (red, green, blue) by the color sensor, and then converted into an electrical image signal. Further, an image processing unit (not shown) performs color conversion processing, color correction processing, spatial frequency correction processing, and the like on the basis of RGB color separation image signals, so that yellow, magenta, cyan, and black are processed. Get color image information.

  Then, image information of each color of yellow, magenta, cyan, and black is transmitted to the writing unit 6. Then, laser light (exposure light) based on the image information of each color is emitted from the writing unit 6 toward the photosensitive drums 11 of the corresponding process cartridges 10Y, 10M, 10C, and 10BK, respectively.

On the other hand, the four photosensitive drums 11 rotate in the clockwise direction in the figure. First, the surface of the photosensitive drum is uniformly charged at a position facing the charging portion (charging roller) (this is a charging process). Thus, a charged potential is formed on the photosensitive drum 11. Thereafter, the surface of the charged photosensitive drum 11 reaches the irradiation position of each laser beam.
In the writing unit 6, laser light corresponding to the image signal is emitted from the light source corresponding to each color. Although not shown, the laser light is incident on the polygon mirror and reflected, and then passes through a plurality of lenses. The laser light after passing through the plurality of lenses passes through different optical paths for each of the yellow, magenta, cyan, and black color components (this is an exposure process).

  Laser light corresponding to the yellow component is irradiated onto the surface of the photosensitive drum 11 of the first process cartridge 10Y from the left side of the drawing. At this time, the yellow component laser light is scanned in the rotational axis direction (main scanning direction) of the photosensitive drum 11 by a polygon mirror (not shown) that rotates at high speed. Thus, an electrostatic latent image corresponding to the yellow component is formed on the photosensitive drum 11 after being charged by the charging roller.

  Similarly, the cyan component laser light is applied to the surface of the photosensitive drum 11 of the second process cartridge 10 </ b> C from the left side of the sheet, thereby forming an electrostatic latent image of the cyan component. The laser beam corresponding to the magenta component is irradiated onto the surface of the photosensitive drum 11 of the third process cartridge 10M from the left side of the paper, and an electrostatic latent image corresponding to the magenta component is formed. The black component laser light is applied to the surface of the photosensitive drum 11 of the process cartridge 10BK (black image forming unit), which is fourth from the left side of the drawing (the most downstream side with respect to the traveling direction of the intermediate transfer belt 17). Thus, an electrostatic latent image of the black component is formed.

Thereafter, the surface of the photosensitive drum 11 on which the electrostatic latent image of each color is formed reaches a position facing the developing unit. Then, each color toner is supplied from each developing unit onto the photosensitive drum 11, and the latent image on the photosensitive drum 11 is developed (this is a developing step).
Thereafter, the surface of the photosensitive drum 11 after the development process reaches a position facing the intermediate transfer belt 17. Here, a primary transfer roller 14 is installed at each facing position so as to contact the inner peripheral surface of the intermediate transfer belt 17. At the position of the primary transfer roller 14, the toner images of the respective colors formed on the photosensitive drum 11 are sequentially transferred to the intermediate transfer belt 17 as an image carrier (in the first transfer process). is there.).

Then, the surface of the photosensitive drum 11 after the first transfer process reaches a position facing the cleaning unit. Then, the untransferred toner remaining on the photosensitive drum 11 is collected by the cleaning unit (cleaning process).
Thereafter, the surface of the photosensitive drum 11 passes through the position of the static eliminating unit, and a series of image forming processes on the photosensitive drum 11 is completed.

On the other hand, the surface of the intermediate transfer belt 17 on which the images of the respective colors on the photosensitive drum 11 are transferred in an overlapping manner travels in the direction of the arrow in the drawing and reaches the position of the secondary transfer roller 18. Then, the full color image on the intermediate transfer belt 17 is secondarily transferred onto the paper P at the position of the secondary transfer roller 18 (second transfer step).
Thereafter, the surface of the intermediate transfer belt 17 reaches the position of the intermediate transfer belt cleaning unit 9. Then, the untransferred toner on the intermediate transfer belt 17 is collected by the intermediate transfer belt cleaning unit 9, and a series of transfer processes on the intermediate transfer belt 17 is completed.

Here, the sheet P at the position of the secondary transfer roller 18 is conveyed from the sheet feeding unit 7 via the conveyance path K1 in which the registration rollers 19 and the like are installed.
Specifically, the paper P fed by the paper feed roller 8 from the paper feed unit 7 that stores the paper P is guided to the registration roller 19 (timing roller) via the transport path K1. The sheet P that has reached the registration roller 19 is conveyed toward the position of the secondary transfer roller 18 in synchronization with the toner image on the intermediate transfer belt 17.

Thereafter, the paper P on which the full color image is transferred is guided to the fixing unit 20. In the fixing unit 20, the color image is fixed on the paper P at the nip between the fixing roller and the pressure roller.
Then, the paper P after the fixing process passes through a conveyance path K2 in which a paper discharge roller 29 and the like are installed, and is discharged as an output image to a paper discharge unit outside the apparatus main body 1 to complete a series of image forming processes. To do. The paper P discharged to the paper discharge unit is subjected to punching processing (punching processing) and binding processing (stapling processing) by the post-processing device 30.

  Note that when the “double-sided print mode” for performing printing on both sides of the paper P (the front side and the back side) is selected, the paper P that has undergone the fixing process on the front side is left as it is. Without being discharged, the paper is guided to the double-sided conveyance path K3, where the conveyance direction is reversed, and then conveyed toward the position of the secondary transfer roller 18 again. Then, an image is formed on the back surface of the sheet P by the same transfer process as described above at the position of the secondary transfer roller 18, and then, after a fixing process in the fixing unit 20, the conveyance path K <b> 2 is passed through. It passes through and is discharged as an output image to a paper discharge unit outside the apparatus main body 1. Even when such a “double-sided print mode” is selected, the post-processing device 30 performs punching processing (punching processing) and binding processing (stapling processing) on the paper P discharged to the paper discharge unit. Will be given.

Hereinafter, the configuration and operation of the post-processing apparatus 30 which are characteristic in the present embodiment will be described in detail with reference to FIGS.
FIG. 2 is a schematic top view showing the operation of the paper P in the post-processing apparatus 30 and is a view of the post-processing apparatus 30 as viewed from above in FIG. FIG. 3 is a schematic view showing the post-processing apparatus 30 as seen from the XX cross section of FIG. FIG. 4 is a schematic top view showing the post-processing apparatus 30 of FIG. FIG. 5 is a side view showing the operation of the clamp unit 70 (two sets of clamp groups 71 and 72 each having two gripping portions are provided), and is an enlarged view of a part of FIG. It is. FIG. 6 is a top view showing the operation of the two clamps 71a and 71b (gripping portions). FIG. 7A is a schematic diagram showing a state in which punching processing by punch pins 32a is performed on the paper P in a wavy state, and FIG. 7B shows punch holes A formed at that time. FIG. 2 is a schematic diagram showing the above (both of which show problems with conventional devices).

As shown in FIG. 2, the sheet P1 on which an image is formed by the apparatus main body 1 is discharged from the apparatus main body 1 to a paper discharge unit in which the post-processing device 30 is installed (indicated by a white arrow in FIG. 2). This is the discharge of the paper P1 in the discharge direction.) Then, by the post-processing device 30, a punching process (in FIG. 2, a punch hole marked with a symbol A of the paper P2) and a binding process (the paper P2 in FIG. This is a portion marked with a symbol B.). Thereafter, the post-processed paper P3 is conveyed in the direction of the black arrow and stacked on the stacking tray 52 (see FIG. 3 and the like) installed at that position (the other end in the width direction). It will be.
As described above, the post-processing device 30 in the present embodiment is in the width direction (the direction perpendicular to the discharge direction and the direction perpendicular to the paper surface of FIG. 1) with respect to the paper P discharged from the image forming apparatus main body 1. .)) Is subjected to perforation processing and binding processing. Therefore, it is possible to perform perforation processing and binding processing on one end side in the short direction of the paper P discharged to the paper discharge unit with the long direction as the discharge direction.

  As shown in FIGS. 2 to 5, the post-processing device 30 according to the present embodiment includes an entrance roller 63, a shift roller 31 as a conveying unit, and a first fence pair 33 (tips) along the moving direction of the paper P. Fence and rear end fence) Clamp unit 70, punch processing section 32, guide 73 (circulation movement mechanism), tray section 38 (staple tray), abutting section 41 (rear end reference fence), second fence pair 40 (jogger fence) ), A staple processing unit 49, a swing mechanism 39, a paper discharge roller 59, a stacking tray unit 52 (paper discharge tray), and the like are installed.

Referring to FIG. 2, the entrance roller 63 is a pair of conveyance rollers for guiding the paper P discharged from the image forming apparatus main body 1 to the inside of the post-processing apparatus 30.
Referring to FIGS. 2 and 4, the shift roller 31 (conveying means) is installed on the downstream side of the entrance roller 63, and conveys the paper P discharged to the paper discharge unit in the discharge direction (in the width direction). It is a direction orthogonal to the discharge direction and is moved toward one end of the vertical direction in FIG. 2 and the horizontal direction in FIGS. 3 and 4. Specifically, the shift roller 31 is configured to be shift-movable in the width direction (in the direction of the double arrow in FIG. 3) by a shift movement mechanism (not shown) while sandwiching and transporting the paper P by a pair of rotating rollers. Then, the paper P discharged to the paper discharge unit is conveyed toward the punch processing unit 32 (and the clamp unit 70).

Although illustration is partially omitted, an entrance sensor (a photo sensor, which is a photo sensor, which detects the leading edge and the trailing edge of the paper P in the conveyance path in which the entrance roller 63 and the shift roller 31 are installed is shown in FIGS. 6 is shown as a black triangle). And the drive timing of the drive part which drives each member which comprises the post-processing apparatus 30 is taken with the detection timing of the front-end | tip of the paper P detected by this entrance sensor, and a rear end.
In addition, since the post-processing device 30 in the present embodiment performs post-processing on one end in the width direction of the paper P discharged from the apparatus main body 1, the punch processing unit 32 and the stapling process are performed on one end in the width direction of the device 30. A portion 49 is provided. Therefore, on the downstream side of the shift roller 31, the transport direction of the paper P is switched to a direction orthogonal to the transport direction in the image forming apparatus main body 1.

3 and 4, the punch processing unit 32 (punch unit) and the clamp unit 70 (gripping unit) are installed on one end side in the width direction with respect to the paper P moved by the shift roller 31. The perforation process is performed on one end in the width direction of the paper P.
Specifically, the paper P is conveyed by the shift roller 31 while being offset toward the one end side in the width direction toward the punch processing unit 32 so that a desired position on one end side in the width direction of the paper P becomes a punch punching position. The The sheet P that has reached the punch processing section 32 is supported in a state where one end in the width direction is supported by the punch processing section 32 and the other end in the width direction is supported by an unillustrated auxiliary tray section (the state shown in FIG. 3). The first fence pair 33 aligns both ends (front and rear ends) of the paper P in the discharge direction. The sheet P is punched by the position of the punch pin 32a in the punch processing unit 32 with one end in the width direction being held by the first clamp group 71 (or the second clamp group 72).
Note that the punching process is performed in a state in which the “waving (bounding)” generated in the paper P is corrected by the operation of the first clamp group 71 (or the second clamp group 72) at this time. This will be described in detail later with reference to FIG.

Here, the punch processing unit 32 may be a known one, and includes a punch stage and a punch pin 32a (a punching member). Further, the punch processing unit 32 is configured to be movable in the vertical direction of FIG. 4 by a shift movement mechanism (not shown) so that the punch punching position can be varied.
The first fence pair 33 is configured such that the distance between the fences can be changed according to the size of the paper P by a shift movement mechanism (not shown). By the first fence pair 33, both ends in the discharge direction of the paper P immediately before the punching process by the punching unit 32 are sandwiched, and the positions in the discharge direction of the paper P are aligned.

  Thereafter, the paper P punched by the punching unit 32 is moved toward the stapling unit 49 by the circulation moving mechanism while being held by the first clamp group 71 (or the second clamp group 72). Further, at this time, the paper P is assisted by the swing mechanism 39 to move on the other side in the width direction (the left side in FIGS. 3 and 4).

  Specifically, referring to FIG. 5, the circulating movement mechanism includes two sets of clamp groups (a first clamp group 71 and a second clamp group 72, each having two clamps as gripping portions. ) Is circulated and moved between the punch processing section 32 and the staple processing section 49 along the guide 73 formed in an annular shape. In the first clamp group 71, a first clamp 71a (installed at a position on the front side in the discharge direction) and a second position are separated from each other in two positions away from each other in the discharge direction (the vertical direction in FIG. 5). A clamp 71b (installed at a position on the rear end side in the discharge direction) is installed. Each of the first clamp 71a and the second clamp 71b is configured to be able to switch between a state in which the paper P is gripped and a state in which the grip state is released. Similarly, in the second clamp group 72, a first clamp 72a and a second clamp 72b are installed at two positions separated in the discharge direction.

As shown in FIG. 5A, first, the paper P conveyed by the shift roller 31 is positioned by the first clamp group 71. Specifically, one end in the width direction of the paper P abuts against the abutting portions of the two clamps 71a and 71b (gripping portions) and is gripped by the two clamps 71a and 71b (gripping portions). In this state, as shown in FIG. 5B, the punch pin 32 a is lowered and the punching process is performed on one end side in the width direction of the paper P.
After that, as shown in FIG. 5C, the punch pin 32a moves to the upper retracted position, and the first clamp group 71 in the state where the punched paper P is gripped moves along the guide 73 ( This is a counterclockwise movement toward the staple processing unit 49). At this time, the second clamp group 72 in the staple processing unit 49 moves along the guide 73 so as to be replaced with the first clamp group 71 without gripping the paper P (toward the punch processing unit 32). This is a counterclockwise movement.)
Then, as shown in FIG. 5D, when the first clamp group 71 moved along the guide 73 is positioned with one end in the width direction of the gripped paper P abutting against the abutting portion 41, the paper The gripping state of P is released, and the apparatus waits at the position of the staple processing unit 49. Thus, the sheet P conveyed to the staple processing unit 49 is placed on the other sheet P stacked on the tray unit 38 in a state where the sheet P is abutted and positioned against the abutting unit 41. On the other hand, the second clamp group 72 reaches the position of the punch processing unit 32 and prepares for the punching process step for the paper P conveyed to that position.
Thereafter, the second clamp group 72 operates as the first clamp group 71 described above, and the first clamp group 71 operates as the second clamp group 72 described above. Then, when the circulation operation of the first clamp group 71 and the second clamp group 72 is repeated as many times as necessary, and a desired number of sheets P (sheet bundle) is stacked on the tray portion 38, The binding process by the stapler 50 is performed on the sheet bundle.
The stapler 50 (staple processing unit 49) can be a known one, and includes a clinching unit and a driver unit.

Here, the swing mechanism 39 assists the operation on the other end side in the width direction of the paper P in the operation of the paper P by the above-described circulation movement mechanism.
Specifically, the swing mechanism 39 has a swing roller 39a (roller) in the forward and reverse directions at the tip of an arm configured to be movable in the vertical and horizontal directions in FIG. It is installed so that it can be rotated. The swing mechanism 39 configured in this way moves to a position where the swing roller 39a holds the paper P together with the paper discharge roller 59, and the sandwiched paper P is moved in the left direction (width) in FIG. (The other end in the direction) can also be conveyed, or the arm P is moved so that the swing roller 39a moves to the one end in the width direction, and the sheet P sandwiched between the tray portion 38 and the other end in the width direction. It can also be moved toward the side.
The sheet P placed on the tray unit 38 by the above-described circulation movement mechanism is accurately determined in the width direction with respect to the stapler 50 by the operation of the above-described swing mechanism 39.

The binding process performed by the staple processing unit 49 and subsequent processes will be described with reference to FIGS.
The sheet P stacked on the tray unit 38 is subjected to alignment processing in the discharge direction of the sheet P by the second fence pair 40 in a state where one end in the width direction is in contact with the abutting part 41. Such a process is performed on a plurality of sheets P, and a plurality of sheets P in a state where the width direction and the discharge direction are aligned on the tray unit 38 (a sheet bundle on which a stapling process is performed). Is loaded. A pressing member configured to be movable in the vertical direction by a moving mechanism (not shown) presses and fixes one end side in the width direction of the plurality of sheets P (sheet bundle) immediately before the binding process is started. Then, the stapling process is performed on the sheet bundle fixed by the pressing member so that the crunch portion of the stapler 50 is lowered and sandwiched between the sheet bundle and the driver portion.
The staple processing unit 49 is configured to be movable in the vertical direction in FIG. 4 by a moving mechanism (not shown) so that the binding position with respect to the paper P can be varied.

Thereafter, when the stapling process is completed, the crunch portion and the pressing member are moved to the upper retracted positions, respectively. Further, the swing roller 39a of the swing mechanism 39 is displaced to a state in which the sheet bundle is sandwiched between the swing roller 39a and the discharge roller 59, and a plurality of sheets subjected to the binding process by the swing roller 39a and the discharge roller 59. P (sheet bundle) is discharged to the stacking tray unit 52.
Here, when the sheet bundle is discharged toward the stacking tray section 52, the solenoid 54 is turned on, the sheet presser 53 is released, and the elevating tray section 52a is lowered by a certain amount. Then, at the timing when the rear end of the sheet bundle passes the position of the paper discharge roller 59, the solenoid 54 is turned off to hold the sheet bundle by the sheet presser 53. Further, at the same timing, the swing mechanism 39 is raised to prepare for receiving the next sheet P.
In this way, on the stacking tray unit 52, a stack of sheets (a plurality of sheets P subjected to binding processing) with stable alignment quality (stackability) is stacked.

  Specifically, referring to FIG. 3, the stacking tray portion 52 has a fixed tray portion formed on the other end side in the width direction (the left side in FIG. 3), and one end side in the width direction (the right side in FIG. 3). ) Is formed with an elevating tray portion 52a (movable tray portion). The elevating tray portion 52a is configured to rotate up and down around a support shaft 52a1 by a cam / link mechanism 56 connected to a DC motor 55. Specifically, the lifting tray portion 52a is pivotally supported by the fixed tray portion via the support shaft 52a1 with the upstream end as a rotational end, and the operating end of the cam / link mechanism 56 is raised and lowered. It is connected to the tray portion 52a. Then, when the number of sheets P discharged to the stacking tray unit 52 reaches a certain number, the DC tray 55 is rotated by the DC motor 55 in response to a command from the control unit. Is displaced so as to descend.

On the other hand, a sheet presser 53 for pressing the sheets P stacked on the stacking tray unit 52 is disposed at a position facing the free end of the elevating tray unit 52a. The paper presser 53 is configured to be able to switch between the operation of releasing the presser of the paper P and the operation of pressing it by the on / off operation of the solenoid 54. Specifically, when the paper P is conveyed, the solenoid 54 is turned on and the pressing operation of the paper presser 53 is released. When the paper P passes the position of the paper discharge roller 59, the solenoid 54 is turned off and the paper presser 53 presses it. Operation is performed.
Although not shown, the paper retainer 53 is provided with a paper surface sensor that detects the paper P stacked on the stacking tray portion 52. When the paper presser 53 is pressing the paper P and the paper surface sensor is in the off state, the lifting tray 52a is raised until the paper surface sensor is turned on. The height of the stacking tray unit 52 on which the sheets P are stacked is kept constant by lowering the lifting tray unit 52a until the sensor is turned off and then raising the lifting tray unit 52a until the sensor is turned on again. Yes.

  In this manner, the free end of the elevating tray unit 52a is moved up and down according to the stacking state of the sheets P on the stacking tray unit 52, and the elevating tray unit 52a is stacked from the nip portion between the swing roller 39a and the paper discharge roller 59. By keeping the distance to the surface constant, the angle (paper discharge angle) at which the paper P discharged from the swing roller 39a contacts the lifting tray 52a can be made constant. Thereby, it is possible to stabilize the alignment quality (stackability) of the sheets P stacked on the stacking tray unit 52 and to stack a large number of sheets P.

  Although the case where both the punching process and the binding process are performed on the paper P has been described so far, the post-processing device 30 in the present embodiment naturally performs only the punching process without performing the binding process. It is also possible to perform only the binding process without performing the punching process. Further, without performing the binding process on the paper P, the paper P is printed for each predetermined number of sheets on the stacking tray 52 as shown in FIG. It is also possible to execute a “shift mode” in which the left and right directions are stacked and sorted.

Here, referring to FIG. 6, the post-processing device 30 in the present embodiment is configured to widen the gripping discharge direction interval with respect to the paper P gripped at a position distant in the discharging direction. In addition, a moving means (moving mechanism) is provided for moving at least one of the two clamps 71a and 71b (grip) in the direction along the discharge direction.
Specifically, the moving unit discharges the two clamps 71a and 71b from each other in a state where one end in the width direction of the paper P discharged from the image forming apparatus main body 1 is held by the two clamps 71a and 71b (gripping portions). It is moved so as to be separated in a direction along the direction (the black arrow direction in FIG. 6C). Specifically, the first clamp 71a moves to the right in FIG. 6, and the second clamp 71b moves to the left in FIG. Although not shown, this moving means (moving mechanism) is a rack gear (formed so as to extend in the discharging direction) integrally formed with the two clamps 71a and 71b. The pinion gear meshes with the rack gear, the stepping motor that rotationally drives the pinion gear under the control of the control unit, and the like.
The two clamps 71a and 71b (gripping portions) are in the width direction (the direction perpendicular to the discharge direction) of the paper P discharged from the image forming apparatus main body 1 as described above with reference to FIG. 6 in the vertical direction of FIG. 6), so that one end in the width direction of the paper P discharged from the image forming apparatus main body 1 can be gripped at two positions apart in the discharge direction. Is formed.

Then, one end in the width direction with respect to the paper P gripped by the two clamps 71a and 71b in a state where the interval in the discharge direction is widened by the movement of the two clamps 71a and 71b by the moving means (moving mechanism) described above. Thus, a punching process by the punch processing unit 32 is performed at a position between the two clamps 71a and 71b.
As a result, even if the sheet P discharged from the apparatus main body 1 undulates in the discharge direction due to the heat received during the fixing process in the apparatus main body 1 or the load received during conveyance, the two sheets of paper 71 P in that state can have two clamps 71a. When the two clamps 71a and 71b move away from each other while being gripped by 71b, 71b, the portion of the paper P sandwiched between the two clamps 71a and 71b is pulled and the undulation is corrected (corrected). To become a plane (or a state close to a plane). And since the punching process by the punch processing part 32 is performed in that state, the trouble that the distorted punch hole A is formed or the punch hole A is displaced from the target position is prevented. .

That is, as shown in FIG. 7A, the punch pin 32a is lowered as it is toward the one end in the width direction with respect to the paper P in a state of undulation in the discharge direction (in the direction of the arrow), and the punching process is performed. Then, as shown in FIG. 7B, a distorted punch hole A (which is distorted in an approximately elliptical shape with respect to a normal punch hole shape indicated by a broken line) is formed. Furthermore, the punch hole A is displaced from the target position.
In contrast, in the present embodiment, the punching process is performed by lowering the punch pin 32a in a state where the corrugated paper sheet P is corrected to a flat shape by the movement of the two clamps 71a and 71b. Defects can be reliably reduced.

Hereinafter, the operation of the two clamps 71a and 71b (gripping portions) will be described in more detail with reference to FIG.
Here, the operation of the two clamps 71a and 71b in the first clamp group 71 when the first clamp group 72 is positioned in the punch processing unit 32 will be described. Since the operations of the two clamps 72a and 72b when they are positioned are the same, the description thereof is omitted.

First, as shown in FIG. 6A, the paper P is conveyed by the shift roller 31 toward the punch processing section 32 (as indicated by the arrow in the figure, discharged while shifting toward one end in the width direction). Transport in the direction.) At this time, the two clamps 71a and 71b move to the standby position in accordance with the detection timing of the leading edge position of the paper P by the entrance sensor (a photosensor, which is illustrated by a black triangle in FIG. 6). (This is the position shown in FIG. 6A.) Then, after a predetermined time has elapsed from the detection timing of the inlet sensor, the conveyance by the shift roller 31 is stopped.
Then, as shown in FIG. 6B, the two clamps 71a and 71b are moved in the direction of the white arrow so as to abut against the paper P by a shift movement mechanism (not shown), and the two clamps 71a and 71b Hold one end of P in the width direction. At this time, the interval between the two clamps 71a and 71b (the interval in the horizontal direction in the figure) is set to a reference value.
Thereafter, as shown in FIG. 6C, the two clamps 71a and 71b move by a predetermined distance M in the black arrow direction while holding the paper P. Thereby, the paper P is in a state in which the undulation is corrected.
Here, the gripping force (holding force) with which the clamps 71 a and 71 b grip the paper P is set to be smaller than the repulsive force of the paper P. As a result, even if the clamps 71a and 71b move a distance larger than the distance at which the corrugation of the paper P is sufficiently corrected, slip occurs between the clamps 71a and 71b and the paper P. It is possible to prevent the paper P from being broken. It is preferable to select materials and shapes of the portions of the clamps 71a and 71b that contact the paper P that satisfy the functions of the clamps 71a and 71b.
Thereafter, as shown in FIG. 6D, the clamp state of the paper P by the shift roller 31 is released, and the two clamps 71a and 71b that hold the paper P in a state where the undulation is corrected are The sheet P moves toward the position in the direction of the white arrow, and the punching unit 32 performs punching processing on one end side in the width direction of the paper P.
Note that the shift roller 31 is configured to be able to switch between the nipping state with respect to the paper P and its release by relatively moving the rollers provided above and below by a contact / separation mechanism (not shown).

Here, in the post-processing apparatus 30 according to the present embodiment, detection by a detection unit that directly or indirectly detects the movement amount M of the two clamps 71a and 71b moved by the movement unit. It can also be varied based on the results.
Specifically, when a thin paper P (for example, a thin paper having a continuous amount of 55K or less) is transported, a normal paper P (for example, a normal paper having a continuous amount of 55 to 90K) is transported. The amount of movement M of the clamps 71a and 71b is set to be larger than that in the case where the sheet is transported. When a thick paper P (for example, a thick paper having a continuous amount of 90K or more) is transported, a normal paper P (for example, a plain paper having a continuous amount of 55 to 90K) is used. The movement amount M of the clamps 71a and 71b is set to be smaller than that in the case of transporting.
This is because undulation is likely to occur when the thickness of the paper P is small (the degree of undulation is large), and undulation is difficult to occur when the thickness of the paper P is large (the degree of undulation is small). By performing such control, it is possible to efficiently perform a drilling process that does not cause problems due to undulations.
The detection means for detecting the thickness of the paper P is based on information directly detected by the paper thickness sensor by installing a paper thickness sensor in the paper conveyance path in the apparatus main body 1 or the post-processing device 30. It may be configured, or may be configured to detect indirectly based on the information of the paper P input by the user on the operation panel installed in the apparatus main body 1 or the post-processing apparatus 30. Also good.

In the present embodiment, the two clamps 71a and 71b are each moved by a moving means (moving mechanism).
On the other hand, referring to FIG. 8, the paper P discharged from the image forming apparatus main body 1 is discharged from the two clamps 71a and 71b in a state where one end in the width direction is gripped by the two clamps 71a and 71b. Moving means (moving mechanism) so as to move only the first clamp 71a (one gripping portion) located on the front end side in the direction away from the second clamp 71b (the other gripping portion) in the direction along the discharge direction. ) Can also be configured.
8A to 8D correspond to FIGS. 6A to 6D, respectively, and here, the operation shown in FIG. 8C is greatly different from that in FIG. become. Specifically, after the same operation as in FIGS. 6A and 6B is performed in FIGS. 8A and 8B, the sheet is fed by two clamps 71a and 71b as shown in FIG. 8C. In a state where P is gripped, the first clamp 71a moves by a predetermined distance M in the black arrow direction (the second clamp 71b does not move). Thereby, the paper P is in a state in which the undulation is corrected. Thereafter, the same operation as in FIG. 6D is performed in FIG. 8D, and the punching process is completed.
Here, it is preferable that the gripping force of the first clamp 71a with respect to the paper P is set to be smaller than the gripping force of the second clamp 71b with respect to the paper P. As a result, even if the first clamp 71a moves a distance larger than the distance at which the corrugation of the paper P is sufficiently corrected, slip occurs between the first clamp 71a and the paper P. It is possible to prevent the paper P from being broken while using the position of the second clamp 71b as a reference. It is preferable to select materials and shapes of the portions of the clamps 71a and 71b that contact the paper P that satisfy the functions of the clamps 71a and 71b.

Further, referring to FIG. 9, the first end in the width direction of the paper P discharged from the image forming apparatus main body 1 is gripped by the shift roller 31 and the first clamp 71a (one gripping portion), and the first The moving means (moving mechanism) can also be configured to move the clamp 71a away from the shift roller 31 in the direction along the discharge direction.
FIGS. 9A to 9D correspond to FIGS. 6A to 6D, respectively, and the operations shown in FIGS. 9B and 9C are the same as those in FIG. Will be very different. Specifically, after the same operation as in FIG. 6A is performed in FIG. 9A, the two clamps 71a and 71b move toward the paper P as shown in FIG. 9B. Unlike the operation of FIG. 6B, only the first clamp 71a holds the paper P (the second clamp 71b does not hold the paper P). At this time, the paper P is held by the shift roller 31 and the first clamp 71a. Then, as shown in FIG. 9C, the first clamp 71a moves by a predetermined distance M in the direction of the black arrow while the sheet P is gripped by the shift roller 31 and the first clamp 71a. Thereby, the paper P is in a state in which the undulation is corrected. Thereafter, the paper P is gripped by the second clamp 71b, and as shown in FIG. 9D, the two clamps 71a and 71b that grip the paper P with the corrected undulation move in the direction of the white arrow to perform punch processing. The punching process by the part 32 is performed. Note that the holding (gripping) of the paper P by the shift roller 31 is released before the operation of FIG.
When such control is performed, referring to FIG. 9C, the first clamp 71a is moved from the distance N1 by the distance N2 with reference to the position of the shift roller 31. The distance from the end to the punch hole becomes difficult to shift from the target position.

  As described above, according to the present embodiment, two clamps are provided so as to widen the gap in the gripped discharge direction for the paper P gripped at two positions separated in the discharge direction. At least one of the clamps 71a of 71a and 71b (grip) is moved in the direction along the discharge direction, and punching by the punch processor 32 is performed on the paper P gripped by the two clamps 71a and 71b in that state. We are processing. As a result, even when the paper P discharged from the image forming apparatus main body 1 is undulated in the discharge direction, a highly accurate punching process can be performed on one end side in the width direction of the paper P.

  It should be noted that the present invention is not limited to the present embodiment, and it is obvious that the present embodiment can be modified as appropriate within the scope of the technical idea of the present invention, other than suggested in the present embodiment. is there. In addition, the number, position, shape, and the like of the constituent members are not limited to the present embodiment, and the number, position, shape, and the like suitable for implementing the present invention can be achieved.

1 image forming apparatus body (apparatus body),
4 Image reading unit,
30 post-processing equipment,
31 Shift roller (conveying means),
32 Punch processing part,
32a punch pin,
33 First fence pair,
38 Tray section,
39 Oscillation mechanism,
39a Swing roller,
40 Second fence pair (jogger fence),
41 The abutment section,
49 Staple processing unit,
50 Stapler,
52 Loading tray section,
52a Lifting tray part,
70 Clamp unit,
71 1st clamp group,
72 second clamp group,
71a, 72a first clamp (one gripping part),
71b, 72b second clamp (the other gripping part),
73 Guide (circulation movement mechanism),
P Paper (recording medium).

Japanese Patent No. 4199203 JP 2010-47419 A

Claims (9)

A post-processing device that performs post-processing on paper ejected from the image forming apparatus main body,
Installed at one end in the width direction orthogonal to the discharge direction of the paper discharged from the image forming apparatus main body, and separated from the one end in the width direction of the paper discharged from the image forming apparatus main body in the discharge direction Two gripping portions formed so as to be gripped at two positions respectively;
At least one of the two gripping portions is set in a direction along the discharge direction so as to widen the gap in the gripping discharge direction with respect to the paper gripped at a position separated in the discharge direction. Moving means for moving;
With respect to the paper gripped by the two gripping portions in a state in which the interval in the discharge direction is widened by the movement of the gripping portion by the moving means, one end side in the width direction and between the two gripping portions A punch processing unit for performing a punching process at a position;
A post-processing device comprising:   The moving means is configured to separate the two gripping portions from each other in the direction along the discharge direction in a state where one end in the width direction of the paper discharged from the image forming apparatus main body is gripped by the two gripping portions. The post-processing apparatus according to claim 1, wherein the post-processing apparatus is moved.   The moving means is one gripping part located on the leading end side in the discharge direction among the two gripping parts in a state where one end side in the width direction of the sheet discharged from the image forming apparatus main body is gripped by the two gripping parts. 2. The post-processing apparatus according to claim 1, wherein only the first gripper is moved away from the other gripping part in a direction along the discharge direction.   The post-processing apparatus according to claim 3, wherein the one gripping portion is formed so that a gripping force with respect to the paper is smaller than a gripping force with respect to the paper of the other gripping portion. A shift roller formed so as to move the paper discharged from the image forming apparatus main body toward one end in the width direction while nipping and conveying the paper discharged in the discharge direction;
The moving means grips one end in the width direction of the paper discharged from the image forming apparatus main body with the shift roller and one of the two gripping portions located on the leading end side in the discharging direction. 2. The post-processing apparatus according to claim 1, wherein in the state, the one gripping portion is moved away from the shift roller in a direction along a discharge direction. Comprising a detecting means for detecting the thickness of the paper directly or indirectly,
The post-processing apparatus according to claim 1, wherein the moving unit varies the amount of movement of the grip portion based on a detection result of the detecting unit. A stapling processing unit that performs binding processing on a plurality of sheets at a position below the punching processing unit,
The circulation movement mechanism which circulates and moves a plurality of sets of the two gripping portions between the punch processing portion and the staple processing portion. The after-treatment device described in   8. An image forming apparatus, wherein the post-processing apparatus according to claim 1 is installed in a paper discharge unit of the image forming apparatus main body.   The image forming apparatus according to claim 8, wherein an image reading unit that reads image information is provided so as to sandwich the post-processing device at a position above the paper discharge unit.

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