JP2014194476A - Image forming system and intermediate device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To correct a slanting paper sheet when a paper conveyance path of an intermediate device is curved so that the problem that the paper sheet is apt to slant during the conveyance when the paper conveyance path is curved to achieve the longer paper conveyance path of the intermediate device is solved.SOLUTION: An intermediate device 30 is provided between a first image forming apparatus 20 on an upstream side in a conveying direction of the paper sheet and a second image forming apparatus 40 on a downstream side and conveys the paper sheet from the first image forming apparatus 20 to the second image forming apparatus 40 via a curved paper conveyance path 31. A resist part 433a is provided on the paper conveyance path 31 in the second image forming apparatus 40 and a resist part 317 is provided on the paper conveyance path 31 in the intermediate device 30 to form a loop of the paper sheet. A quantity of the formed loop of the paper sheet formed by the resist part 317 of the intermediate device 30 is larger than the one formed by the resist part 433a of the second image forming apparatus 40.

Description

  The present invention relates to a tandem image forming system in which a plurality of image forming apparatuses are connected in series, and an intermediate apparatus disposed between the image forming apparatuses.

  2. Description of the Related Art A tandem image forming system (hereinafter simply referred to as “image forming system”) configured by connecting two image forming apparatuses in series is known. According to this image forming system, when images are formed on both sides of a sheet, for example, an image is formed on the front side of the sheet by an upstream image forming apparatus, and an image is formed on the back side of the sheet by a downstream image forming apparatus. it can. By performing the process of forming images on the front and back sides of the paper in a shared manner with each image forming apparatus, productivity is improved compared to the case where images are formed on both sides of the paper with one image forming apparatus. (For example, refer to Patent Document 1).

JP 2012-143964 A

  By the way, an intermediate apparatus having a sheet conveyance path may be disposed between two image forming apparatuses. When the sheet conveyance path of the intermediate apparatus is shorter than the length of the sheet used for image formation in the feeding direction, a part of the sheet is in a state of being applied to one of the image forming apparatuses. For this reason, it is necessary to wait for the image forming operation of the upstream image forming apparatus, or to increase the paper interval during image formation, which decreases productivity.

  In order to lengthen the paper transport path of the intermediate apparatus, a configuration in which the paper transport path is curved in a substantially U shape to lengthen the paper transport path can be considered. However, if the paper transport path is lengthened, the paper is being transported. There arises a problem that the skew becomes easy.

  From the above situation, in an image forming system including a plurality of image forming apparatuses, there has been a demand for a method capable of correcting skewed paper when the paper transport path of the intermediate apparatus is curved.

An image forming apparatus according to an aspect of the present invention includes a first image forming apparatus on the upstream side in the sheet conveying direction, a second image forming apparatus disposed on the downstream side in the sheet conveying direction, the first image forming apparatus, and the second image forming apparatus. And an intermediate device that is disposed between the image forming apparatus and conveys the sheet conveyed from the first image forming apparatus to the second image forming apparatus through a curved sheet conveying path.
A registration unit that forms a loop on the sheet is provided in the sheet conveyance path of the second image forming apparatus. In addition, a registration unit that forms a loop on the paper is provided in the paper conveyance path of the intermediate apparatus.
The amount of loop formation on the sheet by the registration unit of the intermediate apparatus is larger than the amount of loop formation by the registration unit of the second image forming apparatus.

An intermediate apparatus according to one aspect of the present invention is disposed between a first image forming apparatus and a second image forming apparatus, and allows a sheet conveyed from the first image forming apparatus to be second through a curved sheet conveying path. This is an intermediate apparatus that conveys the image to the image forming apparatus.
In the sheet conveyance path of the intermediate apparatus, a registration unit that forms a loop on the sheet is provided.
The loop formation amount for the sheet by the registration unit of the intermediate apparatus is larger than the loop formation amount by the registration unit provided in the second image forming apparatus.

  In the above configuration, the amount of loop formation on the sheet by the registration unit of the intermediate apparatus is larger than the amount of loop formation by the registration unit of the second image forming apparatus. Correction is realized.

  According to the present invention, in an image forming system including a plurality of image forming apparatuses, skewed sheets can be corrected when the sheet conveyance path of the intermediate apparatus is curved.

1 is a schematic diagram illustrating an overall configuration of an image forming system according to an embodiment of the present invention. FIG. 6 is an explanatory diagram illustrating a relationship (first example) between a sheet stop position and a sheet conveyance path of an intermediate apparatus. FIG. 6 is an explanatory diagram illustrating a relationship (second example) between a sheet stop position and a sheet conveyance path of an intermediate apparatus. FIG. 3 is a configuration diagram illustrating a main part (locked state) of a sheet conveyance path of an intermediate apparatus. It is a block diagram which shows the principal part (lock release state) of the paper conveyance path of an intermediate | middle apparatus. It is the 1st explanatory view of lock release operation of an automatic course release mechanism. It is the 2nd explanatory view of lock release operation of an automatic course release mechanism. It is the 3rd explanatory view of lock release operation of an automatic course release mechanism. 2 is a block diagram illustrating an internal configuration of a first image forming apparatus of the image forming system. FIG. It is a block diagram which shows the internal structure of the 2nd image forming apparatus of an image forming system. 6 is a flowchart illustrating jammed paper removal processing in the intermediate apparatus. It is a schematic block diagram of the resist part of a 2nd image forming apparatus. It is a schematic block diagram of the resist part of an intermediate | middle apparatus. It is a schematic diagram explaining the loop formed with the resist part of a 2nd image forming apparatus. It is a schematic diagram explaining the loop formed with the resist part of an intermediate | middle apparatus. It is the schematic which shows the modification of the whole structure of the image forming system which concerns on one embodiment of this invention.

  Hereinafter, an example of an embodiment for carrying out the present invention will be described with reference to the accompanying drawings. In addition, in each figure, the same code | symbol is attached | subjected to the common component and the overlapping description is abbreviate | omitted.

[Overall configuration of image forming system]
First, an outline of an image forming system according to an embodiment of the present invention will be described with reference to FIG.
FIG. 1 is a schematic diagram showing the overall configuration of an image forming system according to an embodiment of the present invention.
As shown in FIG. 1, the image forming system 1 includes a paper feeding device 10, a first image forming device 20, an intermediate device 30, a second image forming device 40, a post-processing device 50, and the like from the upstream side of the paper conveyance path. Are connected in series.

  When the first image forming apparatus 20 and the second image forming apparatus 40 are connected, they are either a main machine that comprehensively manages the image forming system 1 or a sub machine that operates according to an instruction of the main machine Is set. In the present embodiment, it is assumed that the first image forming apparatus 20 provided on the upstream side in the sheet conveyance direction is set as the main machine, and the second image forming apparatus 40 is set as the sub machine.

In the image forming system 1 according to the present embodiment, when executing a duplex mode job for forming images on both sides of a sheet, the first image forming apparatus 20 forms an image on one side of the sheet. The second image forming apparatus 40 functions as a second image forming apparatus that forms an image on the other side of the sheet.
When executing a job in the duplex mode, the first image forming apparatus 20 forms an image on the front surface of the sheet conveyed from the sheet feeding device 10 or the sheet feeding unit in the first image forming apparatus 20. Then, the sheet on which the image on the front surface is formed is reversed by the reversing unit in the first image forming apparatus 20, and then is conveyed to the second image forming apparatus 40 through the intermediate apparatus 30. An image is formed on the back surface and conveyed to the post-processing device 50.

  When a single-side mode job for forming an image on one side of a sheet is executed, the first side is applied to one side of the sheet conveyed from the sheet feeding unit in the sheet feeding device 10 or the first image forming apparatus 20. The image forming apparatus 20 forms an image. Then, the sheet on which the image is formed on one side passes through the intermediate device 30 and the second image forming device 40 and is conveyed to the post-processing device 50.

(Paper feeder)
The paper feeder 10 is called a PFU (Paper Feed Unit), and includes a plurality of paper feed trays, a paper feed means including a paper feed roller, a separation roller, a paper feed / separation rubber, a feed roller, and the like. Prepare. Each sheet tray stores sheets identified in advance for each sheet type (sheet type, basis weight, sheet size, etc.), and the first image is formed by sheet feeding means one by one from the top of the sheet. The sheet is conveyed to the sheet conveying unit of the apparatus 20. Information on the paper type (paper size, paper type, etc.) stored for each paper feed tray is stored in a non-volatile memory 251 (to be described later) of the first image forming apparatus 20. The paper feeding device 10 functions as a paper feeding unit of the first image forming device 20.

(First image forming apparatus)
The first image forming apparatus 20 reads an image from a document, and forms the read image on a sheet. Also, print data and print setting data in a page description language format such as a PDL (Page Description Language) format and a Tiff format are received from an external device, etc., and an image is placed on a sheet based on the received print data and print setting data. Or form. The first image forming apparatus 20 includes an image reading unit 21, an operation display unit 22, a print unit 23, and the like.

  The image reading unit 21 includes an automatic document feeding unit called ADF (Auto Document Feeder) and a reading unit, and reads images of a plurality of documents based on setting information received by the operation display unit 22. The document placed on the document tray of the automatic document feeder is conveyed to a contact glass as a reading location, and an image on one or both sides of the document is read by an optical system, and a CCD (Charge Coupled Device) 211 (see FIG. 9). ) Reads the image of the document. Here, the image means not only image data such as graphics and photographs but also text data such as characters and symbols.

  The operation display unit 22 includes an LCD (Liquid Crystal Display) 221, a touch panel provided to cover the LCD 221, various switches and buttons, a numeric keypad, an operation key group, and the like. The operation display unit 22 receives an instruction from the user and outputs the operation signal to the control unit 250 described later. Further, according to a display signal input from the control unit 250, various setting screens for inputting various operation instructions and setting information, and operation screens for displaying various processing results are displayed on the LCD 221.

  The print unit 23 performs electrophotographic image forming processing, and includes various units related to print output, such as a paper feed unit 231, a paper transport unit 232, an image forming unit 233, and a fixing unit 234. In addition, although the example which applied the electrophotographic system is demonstrated in the printing part 23 of this Embodiment, you may apply other printing systems, such as not only this but an inkjet system and a thermal sublimation system.

  The sheet feeding unit 231 includes a plurality of sheet feeding trays and sheet feeding means including a sheet feeding roller, a separation roller, a sheet feeding / separating rubber, a feeding roller, and the like provided for each sheet feeding tray. Each paper tray stores paper that can be fed in advance identified for each paper type (paper type, basis weight, paper size, etc.), and feeds paper one by one from the top of the paper. It is conveyed toward the paper conveyance unit. Information on the type of paper (paper type, basis weight, paper size, etc.) stored for each paper feed tray is stored in the nonvolatile memory 251.

  The sheet conveying unit 232 conveys the sheet conveyed from the sheet feeding device 10 or the sheet feeding unit 231 onto a sheet conveying path to the image forming unit 233 that passes through a plurality of intermediate rollers, registration rollers, and the like. Then, it is conveyed to the transfer position of the image forming unit 233 and further conveyed to the second image forming apparatus 40. The sheet temporarily stands by at the upstream side of the registration roller 233a for correcting the bending, and the conveyance to the downstream side of the registration roller 233a is resumed according to the image formation timing.

  The paper transport unit 232 includes a reversing unit 232b including a transport path switching unit 232a and a reversing roller. In accordance with the switching operation of the conveyance path switching unit 232a, the reversing unit 232b conveys the sheet that has passed through the fixing unit 234 to the apparatus connected downstream without being reversed, or switches back by a reversing roller or the like. Then, the paper is turned upside down and then conveyed to an apparatus connected downstream. Further, the reversing unit 232b may include a circulation path unit that reverses the front and back of the sheet that has passed through the fixing unit 234 and refeeds the image to the image forming unit 233 of the first image forming apparatus 20.

  The image forming unit 233 includes a photosensitive drum, a charging device, an exposure device, a developing device, a transfer device, a cleaning device, and the like, and forms an image on a sheet surface based on print image data. In the case where the first image forming apparatus 20 forms a color image, an image forming unit 233 is provided for each color (Y, M, C, Bk).

  In the image forming unit 233, the surface of the photosensitive drum charged by the charging device is irradiated with light corresponding to the print image data from the exposure device, and an electrostatic latent image is written. Then, the toner charged by the developing device is attached to the surface of the photosensitive drum on which the electrostatic latent image is written, and the electrostatic latent image is developed. The toner image attached on the photosensitive drum is transferred to the paper at the transfer position. After the toner image is transferred to the paper, the cleaning device removes residual charge, residual toner, and the like on the surface of the photosensitive drum, and the removed toner is collected in a toner collection container.

  The fixing unit 234 includes a fixing heater, a fixing roller, a fixing external heating unit, and the like, and thermally fixes the toner image transferred to the sheet.

(Intermediate device)
The intermediate device 30 is installed on the downstream side of the first image forming device 20 and the upstream side of the second image forming device 40 in the paper transport direction. In the present embodiment, the intermediate apparatus 30 conveys the sheet conveyed from the first image forming apparatus 20 to the second image forming apparatus 40 in accordance with an instruction from the second image forming apparatus 40.
The length of the sheet conveyance path 31 of the intermediate apparatus 30 is such that when the intermediate apparatus 30 or the second image forming apparatus 40 instructs the sheet conveyance path 31 to stop the sheet, the first image forming apparatus 20 It is formed so that the end is not applied. When viewed from the front side of the intermediate device 30, the sheet conveyance path 31 is configured to bend from the vicinity of the conveyance roller 311 on the sheet carry-in side to the vicinity of the conveyance roller 318 on the sheet discharge side. In the present embodiment, the curved shape of the paper transport path 31 is a substantially U-shape that is convex downward. By curving the paper transport path 31, the length of the paper transport path 31 can be secured in a limited space. In other words, by curving the sheet conveyance path 31, it is possible to reduce the size of the intermediate device 30 while ensuring the length of the sheet conveyance path 31.

Examples of the length required for the paper transport path 31 include the following.
First, when a sheet stop position is provided in the middle of the sheet conveyance path of the second image forming apparatus 40, the length of the sheet conveyance path 31 is based on the leading edge of the sheet stopped in the second image forming apparatus 40. The trailing edge of the sheet is formed so as to fit in the intermediate device 30.
Second, in the case where a sheet stop position is provided in the middle of the sheet conveyance path 31 of the intermediate apparatus 30, the length of the sheet conveyance path 31 is based on the leading edge of the sheet stopped in the intermediate apparatus 30 as a base point. Is formed so as to fit in the intermediate device 30.

FIG. 2 is an explanatory diagram illustrating a relationship (first example) between the sheet stop position and the sheet conveyance path 31 of the intermediate apparatus 30.
In the example of FIG. 2, the registration roller 433a of the second image forming apparatus 40 is set to the paper stop position. In this case, the length of the sheet conveyance path 31 is set so that the rear end of the sheet S is accommodated in the intermediate apparatus 30 with the nip portion of the registration roller 433a of the second image forming apparatus 40 as the base point of the leading end of the sheet S. Is formed. The rear end of the sheet is located in the middle of the sheet conveyance path 31 of the intermediate apparatus 30, for example, near the conveyance roller 315.

FIG. 3 is an explanatory diagram showing a relationship (second example) between the maximum length in the sheet feeding direction and the sheet conveyance path 31 of the intermediate apparatus 30.
In the example of FIG. 3, the registration roller 317 of the intermediate device 30 is at the paper stop position. In this case, the length of the sheet conveyance path 31 is formed such that the rear end of the sheet S is within the intermediate apparatus 30 with the nip portion of the registration roller 317 of the intermediate apparatus 30 as the base point of the leading end of the sheet S. Yes. The rear end of the sheet is located near the conveyance roller 311 on the sheet carry-in side of the sheet conveyance path 31 of the intermediate device 30.

  The intermediate device 30 also includes an automatic path opening mechanism 32 (an example of a path opening mechanism) that opens the paper transport path 31 when a jam occurs. Jam means that the paper is abnormally stopped for some reason in the image forming system 1, and the paper that is abnormally stopped in the image forming system 1 is called jammed paper. The action of removing paper (residual paper) other than the jammed paper that has been stopped is described as jam processing.

  When a jam occurs in the paper transport path 31, the automatic path opening mechanism 32 opens a part of the paper transport path 31, so that the paper remaining in the paper transport path 31 when the jam occurs is disposed below. It is configured to accommodate. The intermediate device 30 includes a door open / close detection sensor 30 d that detects an open / closed state of a front door (not shown) and outputs a detection result to the second image forming device 40. The automatic path opening mechanism 32 is opened, for example, by detecting a signal output from the door opening / closing detection sensor 30d indicating that the front door has been opened. The user can restart the operation of the image forming system 1 by removing the jammed paper and the paper whose conveyance has been stopped in the paper conveyance path 31, that is, by performing jam processing.

(Second image forming apparatus)
The second image forming apparatus 40 includes a print unit 43 and the like, and forms an image on the sheet surface in cooperation with the first image forming apparatus 20.
The sheet conveyed from the first image forming apparatus 20 is conveyed to the registration roller 433a via the conveyance roller 434a. The sheet temporarily stands by on the upstream side of the registration roller 433a, and the conveyance to the downstream side of the registration roller 433a is resumed according to the image formation timing.
Note that the print unit 43 included in the second image forming apparatus 40 is similar to the print unit 23 included in the first image forming apparatus 20. Since each part relating to print output, such as a part, is configured, description thereof is omitted.

(Post-processing equipment)
The post-processing device 50 is installed on the downstream side of the second image forming apparatus in the paper conveyance direction, and includes various post-processing units such as a sorting unit, a stapling unit, a punching unit, and a folding unit, and a paper discharge tray (large capacity A sheet discharge tray T1, a sub-tray T2), and the like, and various types of post-processing are performed on the sheet conveyed from the second image forming apparatus 40. Discharge. The large-capacity discharge tray T1 has a stage that moves up and down, and accommodates a large amount of sheets stacked on the stage. On the sub-tray T2, the paper is exposed to the outside and discharged in a visible state.

(Main parts of the paper transport path and its surroundings)
Here, the configuration of the automatic path opening mechanism 32 of the intermediate apparatus 30 in the image forming system 1 having the above configuration will be further described.
FIG. 4 illustrates a configuration of a main part (locked state) of the sheet conveyance path 31 when the intermediate device 30 is viewed from the front. FIG. 5 shows a configuration of a main part (unlocked state) of the sheet conveyance path 31 when the intermediate device 30 is viewed from the front.

As shown in FIG. 4, the intermediate device 30 includes a sheet conveyance path 31 that is curved downward, and an automatic path opening mechanism 32.
The sheet conveyance path 31 in the intermediate device 30 includes a curved plate-shaped inner guide portion 31a, curved plate-shaped fixed guide portions 31b and 31c provided to face the inner guide portion 31a, and a downward direction. It is comprised from the 1st movable guide part 34 and the 2nd movable guide part 35 (an example of a movable guide part) which can be rotated. The first movable guide part 34 has a plate-like guide part 343 provided so as to face the inner guide part 31a, and the second movable guide part 35 is provided so as to face the inner guide part 31a. A plate-shaped guide portion 353 is provided.
From the upstream side in the paper transport direction, the fixed guide portion 31b, the guide portion 343, the guide portion 353, and the fixed guide portion 31c are arranged in this order.
A plurality of rollers are arranged along the paper conveyance path 31. FIG. 4 shows a curl correction roller 314, a conveyance roller 315, a conveyance roller 316, a registration roller 317, and a conveyance roller 318. The conveyance roller 316 is also a loop creation roller for forming a loop on the paper.

The inner guide portion 31a and the fixed guide portions 31b and 31c are fixed to the back surface 30A of the intermediate device 30 directly or via an arbitrary member.
The inner guide portion 31a constitutes a fixed guide portion that is fixed inside the sheet conveyance path 31 curved downward. On the other hand, the fixed guide portions 31 b and 31 c, the guide portion 343 of the first movable guide portion 34, and the guide portion 353 of the second movable guide portion 35 constitute a guide portion outside the paper transport path 31.
The fixed guide portions 31b and 31c, the guide portion 343 of the first movable guide portion 34, and the guide portion 353 of the second movable guide portion 35 are curved along the curved shape of the inner guide portion 31a. In addition, the shape of the 1st movable guide part main body 341 is also curved so that the curved shape of the inner side guide part 31a may be followed.

The first movable guide portion 34 includes a first movable guide portion main body 341 that is pivotally supported by a rotation shaft portion 342 provided at an upstream end portion in the sheet conveyance direction. The first movable guide portion main body 341 is rotationally driven so as to open the upstream side downward by a guide portion drive mechanism (not shown). The rotation shaft portion 342 is orthogonal to the paper transport direction. One end of each of the various rollers and the rotation shaft portion 342 is attached to a fixed plate 36 disposed on the back surface 30 </ b> A side inside the intermediate device 30. The other ends of the various rollers and the rotation shaft portion 342 are attached to a fixed plate 37 (see FIG. 6) disposed on the front side inside the intermediate device 30.
A locking member 344 is pivotally supported by a rotation shaft portion 345 at a predetermined position of the first movable guide portion main body 341. The locking member 344 has a pivot shaft 345 passed through one end and a hook-shaped hook 344a formed at the other end.

The hook portion 344a of the locking member 344 is hooked on the fixed pin 371 shown in FIG. 6, so that the first movable guide portion main body 341 is locked, and thereby the sheet can be guided (guide position). Held in the locked state.
When the first movable guide portion main body 341 and the second movable guide portion main body 351 are locked, the distal end portion 341t of the first movable guide portion main body 341 and the distal end portion 351t of the second movable guide portion main body 351 are close to each other. , Are arranged in opposition.

On the other hand, when the key portion 344a of the locking member 344 is not hooked on the fixed pin 371, the upstream side of the first movable guide portion main body 341 rotates clockwise around the rotation shaft portion 342 by its own weight. (Open position), the paper transport path 31 is opened (unlocked state) (see FIG. 5).
A driven roller 317b of a registration roller 317 is attached to the first movable guide portion main body 341, and the driven roller 317b moves as the first movable guide portion main body 341 rotates. As described above, when the first movable guide portion main body 341 is opened, the driven roller 317b of the registration roller 317 is retracted integrally with the rotation operation of the first movable guide portion main body 341, and the pressure contact of the registration roller 317 is released.

The second movable guide part 35 has a shape that is substantially symmetrical to the first movable guide part 34 with respect to the intermediate point of the paper transport path 31, and is composed of substantially the same elements as the first movable guide part 34.
The second movable guide portion main body 351 of the second movable guide portion 35 is pivotally supported by a pivot shaft portion 352 provided at an end on the upstream side in the paper transport direction. The second movable guide portion main body 351 is rotationally driven so as to open the downstream side downward by a guide portion drive mechanism (not shown). The rotation shaft portion 352 is orthogonal to the paper transport direction. One end of the rotation shaft portion 352 is attached to a fixed plate 36 disposed on the back surface 30 </ b> A side inside the intermediate device 30. Further, the other end of the rotation shaft portion 352 is attached to a fixed plate 37 (see FIG. 8) disposed on the front side of the intermediate device 30.
A locking member 354 is pivotally supported by a rotation shaft portion 355 at a predetermined position of the second movable guide portion main body 351. The locking member 354 has a pivot shaft 355 passed through one end and a hook-shaped hook 354a formed at the other end.

  The hook portion 354a of the locking member 354 is hooked on the fixing pin 372 shown in FIG. 6, whereby the second movable guide portion main body 351 is locked, thereby enabling the sheet to be guided (guide position). Held in the locked state.

On the other hand, when the key portion 354a of the locking member 354 is not hooked on the fixed pin 372, the downstream side of the second movable guide portion main body 351 rotates counterclockwise around the rotation shaft portion 352 by its own weight. Then, the sheet conveyance path 31 is opened (unlocked state) (see FIG. 5).
A driven roller 316b of a transport roller 316 is attached to the second movable guide portion main body 351, and the driven roller 316b moves as the second movable guide portion main body 351 rotates. Thus, when the second movable guide portion main body 351 is opened, the driven roller 316b of the transport roller 316 is retracted integrally with the rotation operation of the second movable guide portion main body 351, and the pressure contact of the transport roller 316 is released.

  The operation unit 346 pivotally supported by the rotation shaft portion 345 of the first movable guide portion main body 341 and the operation portion 356 pivotally supported by the rotation shaft portion 355 of the second movable guide portion main body 351 are the first movable guide. This is used to return the main part body 341 and the second movable guide part main body 351 to the locked position. For example, when the user returns the first movable guide portion main body 341 and the second movable guide portion main body 351 to the lock position and operates the operation portion 346 and the operation portion 356, the locking members 344 and 354 are respectively connected to the fixing pins 371, 371, respectively. It is latched by 372 and becomes a locked state. The driven roller 317 b of the registration roller 317 is disposed at a position close to the rotation shaft portion 342 on the downstream side of the operation portion 346.

As described above, the automatic path opening mechanism 32 according to the present embodiment includes the first movable guide portions 34 and 35 that open the paper transport path 31. The first movable guide portions 34 and 35 rotate about the rotation shaft portions 342 and 352, and include first and second movable guide portion main bodies 341 and 351 provided with guide portions 343 and 353 for guiding paper, A lock mechanism for holding the first and second movable guide main bodies 341 and 351 is provided at a position where the sheet can be guided. Furthermore, a lock release mechanism that releases the locked state of the first and second movable guide portion main bodies 341 and 351 when a jam occurs and a driven roller 317b of the registration roller 317 are provided.
When the jam occurs, the first movable guide portion main body 341 is opened, and the driven roller 317b of the registration roller 317 moves together with the opening operation, so that the pressure contact of the registration roller 317 is released. At the same time, the second movable guide portion main body 351 is opened, and the driven roller 316b of the conveying roller 316 moves together with the opening operation, so that the pressure contact of the conveying roller 316 is released. With this configuration, the paper remaining in the paper transport path 31 is stored in the storage unit 33, and the user can collect and remove these papers.

  A curl correction roller 314 (an example of a curl correction unit) is provided on the upstream side of the conveyance roller 315 disposed in the paper conveyance path 31. Further, on the upstream side of the curl correction roller 314, a curl detection unit (not shown) for detecting the direction and degree of curl of the paper is installed. The curl correction roller 314 corrects the curl of the paper using, for example, a pair of rollers having different hardness based on the detection result by the curl detection unit. As another example, the curl correction unit may be configured using a roller and a belt.

[Unlocking operation of automatic path opening mechanism]
Next, the unlocking operation of the automatic path opening mechanism 32 will be described.
FIG. 6 is a first explanatory diagram of the unlocking operation of the automatic path opening mechanism 32.
FIG. 7 is a second explanatory diagram of the unlocking operation of the automatic path opening mechanism 32.
FIG. 8 is a third explanatory diagram of the unlocking operation of the automatic path opening mechanism 32.

  Fixing pins 371 and 372 are erected on the front surface of the fixing plate 37 disposed on the front surface side of the intermediate device 30. As shown in FIG. 8, when the automatic path opening mechanism 32 is not opened, that is, when the first movable guide portion 34 is in the locked state, the key portion 344a of the locking member 344 provided in the first movable guide portion 34 is fixed. It is hooked on the pin 371. Similarly, a hook portion 354 a of a locking member 354 included in the second movable guide portion 35 is hooked on the fixed pin 372.

The lock release mechanism 38 includes a swing cam 381 and an eccentric cam 384.
The swing cam 381 has a substantially sector shape, is pivotally supported by a rotation shaft 382 located at a position corresponding to the crimped portion of the fan, and is displaced about the rotation shaft 382. The swing cam 381 is formed with guide holes 383 for guiding the eccentric cam 384 and guide holes 385 and 386 for guiding the guide pins 387 and 388 at predetermined positions. The guide pins 387 and 388 are erected on the front surface of the fixed plate 37. A guide pin 387 and a guide pin 388 are arranged in this order from the side close to the rotation shaft 382.

  The eccentric cam 384 is driven to rotate about the rotation shaft 384a by an eccentric cam driving unit (not shown) under the control of the swing cam drive control unit 471. As the eccentric cam drive unit, a combination of a motor and various mechanisms and various actuators can be employed. When the eccentric cam 384 rotates, the distance from the rotation shaft 384 a to the edge of the guide hole 383 changes and contacts the edge of the guide hole 383. As a result, the swing cam 381 swings left and right about the rotation shaft 382. The position of the swing cam 381 shown in FIG. 6 is a home position (see FIG. 4) in which neither the first movable guide part 34 nor the second movable guide part 35 is released.

  An escape portion 381c having a concave shape corresponding to the curved surface of the drive roller 317a is formed on the outer peripheral portion of the swing cam 381 facing the drive roller 317a of the registration roller 317. In addition, an escape portion 381d having a concave shape corresponding to the curved surface of the driving roller 316a is formed in a portion of the outer peripheral portion of the swing cam 381 facing the driving roller 316a of the conveying roller 316. By these escape portions 381c and 381d, even if the swing cam 381 swings left and right, the outer peripheral portion of the swing cam 381 does not contact each drive roller. By adopting such a shape, the swing cam 381 is reduced in size.

  As shown in FIG. 7, when the eccentric cam 384 rotates and the left diameter of the rotating shaft 384a becomes longer, the swing cam 381 is displaced leftward. Thereby, the protrusion 381a of the swing cam 381 pushes out the key part 344a of the locking member 344 included in the first movable guide part 34. When the key portion 344a of the locking member 344 is pushed out, the locked state of the first movable guide portion 34 is released, and the first movable guide portion main body 341 is released by its own weight (see FIG. 5).

  As shown in FIG. 8, when the eccentric cam 384 continues to rotate further from the state shown in FIG. 7 and the diameter on the right side of the rotation shaft 384a of the eccentric cam 384 becomes longer, the swing cam 381 is displaced rightward. . Thereby, the protrusion 381a of the swing cam 381 pushes out the key part 354a of the locking member 354 provided in the second movable guide part 35. When the key portion 344a of the locking member 354 is pushed out, the locked state of the second movable guide portion 35 is released, and the second movable guide portion main body 351 is released by its own weight (see FIG. 5).

  After the rocking cam 381 is displaced in the right direction and pushes the key portion 354a of the locking member 354 included in the second movable guide portion 35, the eccentric cam 384 is moved by a phase actuator on the eccentric cam drive shaft (not shown). Rotate to the home position (see Fig. 6) and stop.

  The unlocking operation of the automatic path opening mechanism 32 using the swing cam 381 disposed on the front side of the intermediate device 30 has been described above with reference to FIGS. 6 to 8. The path opening mechanism 32 is also arranged on the back surface 30 </ b> A side inside the intermediate device 30. However, the automatic path opening mechanism 32 including the swing cam 381 may be disposed at least on either the back surface 30A side or the front surface side.

[Internal configuration of first image forming apparatus]
FIG. 9 is a block diagram showing an internal configuration of the first image forming apparatus 20 of the image forming system 1.
As shown in FIG. 9, the first image forming apparatus 20 includes an image reading unit 21, an operation display unit 22, a printing unit 23, a controller 24, an image control board 25, a communication unit 26, and the like. The first image forming apparatus 20 is connected to the external apparatus 2 on the network 3 via a LANIF (Local Area Network InterFace) 244 of the controller 24 so that data can be transmitted and received between them.

  The image reading unit 21 includes the automatic document feeding unit and reading unit described above, and the image reading control unit 210. The image reading control unit 210 controls the automatic document feeding unit, the reading unit, and the like based on an instruction from the control unit 250 to realize a scanner function that reads images of a plurality of documents. The analog image data read by the image reading unit 21 is output to the reading processing unit 253, where the reading processing unit 253 performs A / D conversion and various image processing.

  The operation display unit 22 includes the above-described LCD 221, touch panel, and the like, and an operation display control unit 220. The operation display control unit 220 causes the LCD to display various screens for inputting various setting conditions and various processing results in accordance with a display signal input from the control unit 250. The operation display control unit 220 outputs operation signals input from various switches, buttons, numeric keys, operation key groups, a touch panel, and the like to the control unit 250.

  The print unit 23 includes units related to print output, such as the above-described paper feed unit 231, paper transport unit 232, image forming unit 233, fixing unit 234 (see FIG. 1), and a print control unit 230. The print control unit 230 controls the operation of each unit of the print unit 23 such as the image forming unit 233 according to an instruction from the control unit 250, and causes the image formation to be performed based on the print image data input from the writing processing unit 258. .

The controller 24 manages and controls data input to the image forming system 1 from the external device 2 connected to the network 3. The controller 24 receives data to be printed (print data and print setting data) from the external device 2, and transmits image data and print setting data generated by expanding the print data to the image control board 25.
The controller 24 includes a controller control unit 241, a DRAM (Dynamic Random Access Memory) control IC 242, an image memory 243, a LANIF 244, and the like.

  The controller control unit 241 comprehensively controls the operation of each unit of the controller 24 and develops print data input from the external apparatus 2 via the LANIF 244 to generate bitmap format image data.

  The DRAM control IC 242 controls transfer of print data received by the LANIF 244 to the controller control unit 241 and writing / reading of image data and print setting data to / from the image memory 243. The DRAM control IC 242 is connected to the DRAM control IC 255 of the image control board 25 by a PCI (Peripheral Components Interconnect) bus. The DRAM control IC 242 reads out image data to be printed and print setting data from the image memory 243 according to an instruction from the controller control unit 241 and outputs them to the DRAM control IC 255.

  The image memory 243 is composed of a volatile memory such as a DRAM, and temporarily stores image data and print setting data.

  The LANIF 244 is a communication interface for connecting to a network 3 such as a network interface card (NIC) or a modem such as a modem, and receives print data and print setting data from the external device 2. The received print data and print setting data are output to the DRAM control IC 242.

  The image control board 25 includes a control unit 250, a nonvolatile memory 251, a RAM (Random Access Memory) 252, a reading processing unit 253, a compression IC 254, a DRAM control IC 255, an image memory 256, a decompression IC 257, a writing processing unit 258, and the like.

  The control unit 250 is configured by a CPU (Central Processing Unit) and the like, reads a system program stored in the nonvolatile memory 251 and various programs specified in the application program, and develops them in the RAM 252. The control unit 250 executes various processes in cooperation with the program developed in the RAM 252 and performs centralized control of each unit of the first image forming apparatus 20.

  In addition, since the first image forming apparatus 20 is set as the main machine, the control unit 250 receives a signal indicating the state of each apparatus from each apparatus constituting the image forming system 1 via the communication unit 26. To do. The control unit 250 comprehensively controls the entire image forming system 1 based on a signal indicating the state of each apparatus. For example, when a signal indicating an error in the second image forming apparatus 40 (JAM occurrence, out of paper, toner shortage, etc.) is received, a display signal or an operation instruction signal corresponding to the error is generated and the generation is performed. The transmitted signal is transmitted to the operation display unit 22 and the second image forming apparatus.

  The control unit 250 also includes image data and print setting data input from the external device 2 via the controller 24, or image data input from the image reading unit 21 and setting information set by the operation display unit 22, Job data and compressed image data are generated based on the above. Then, the control unit 250 executes the job in cooperation with the second image forming apparatus 40 based on the generated job data and compressed image data.

  A job is a series of operations related to image formation. For example, when a copy made of a document of a predetermined page is created, a series of operations related to image formation of a document of a predetermined page is one job. Data for executing this job operation is job data.

The job data includes job information and page information.
The job information is information common to all pages. For example, the job information includes the number of copies set for the job, a paper discharge tray, application functions (such as aggregation and repeat), and color / monochrome.
The page information is associated with the compressed image data of each page, and is information related to the associated compressed image data. For example, page information includes page number, image size (vertical, horizontal), image orientation, image width, image rotation angle, paper type on which the image is formed, paper feed tray in which the paper is stored, It includes a print mode (double-sided mode / single-sided mode), a storage address of compressed image data, and the like.

  The nonvolatile memory 251 stores various processing programs related to image formation, various data, and the like. The non-volatile memory 251 stores the types of paper stored in the paper feed trays provided in the paper feed device 10, the paper feed unit of the first image forming device 20, and the paper feed unit of the second image forming device 40, respectively. I remember information.

The RAM 252 forms a work area that temporarily stores various programs executed by the control unit 250 and various data related to these programs.
The RAM 252 also stores image data and print setting data input from the controller 24, or image data input from the image reading unit 21 and setting information set by the operation display unit 22 when the image data is acquired. , The job data generated by the control unit 250 is temporarily stored.

  The reading processing unit 253 generates digital image data after performing various processing such as analog processing, A / D conversion processing, and shading processing on the analog image data input from the image reading unit 21. The generated image data is output to the compression IC 254.

  The compression IC 254 performs a compression process on the input digital image data and outputs it to the DRAM control IC 255.

  The DRAM control IC 255 controls image data compression processing by the compression IC 254 and decompression processing of compressed image data by the decompression IC 257 in accordance with instructions from the control unit 250, and performs input / output control of image data to the image memory 256.

  For example, when an instruction to save image data read by the image reading unit 21 is input from the control unit 250, the DRAM control IC 255 causes the compression IC 254 to perform compression processing of the image data input to the reading processing unit 253. The compressed image data is stored in the compression memory 256a of the image memory 256. In addition, when image data is input from the DRAM control IC 242 of the controller 24, the DRAM control IC 255 causes the compression IC 254 to execute compression processing of the image data, and stores the compressed image data in the compression memory 256a of the image memory 256.

  Further, when the print control instruction for the compressed image data stored in the compression memory 256a is input from the control unit 250, the DRAM control IC 255 reads the compressed image data from the compression memory 256a and performs decompression processing by the decompression IC 257. The data is stored in the memory 256b. Further, when a print output instruction for image data stored in the page memory 256 b is input, the image data is read from the page memory 256 b and output to the writing processing unit 258.

  The image memory 256 includes a compression memory 256a and a page memory 256b composed of DRAM (Dynamic RAM). The compression memory 256a is a memory for storing compressed image data. The page memory 256b temporarily stores image data for print output or temporarily stores image data received from the controller before compression. It is a memory to do.

  The decompression IC 257 performs decompression processing on the compressed image data.

  The write processing unit 258 generates print image data for image formation based on the image data input from the DRAM control IC 255 and outputs the print image data to the print unit 23.

  The communication unit 26 is a communication interface for connecting to a network to which each device constituting the image forming system 1 is connected. For example, the communication unit 26 communicates with the second image forming apparatus 40 using a NIC (Network Interface Card) or the like, and performs serial communication with the sheet feeding apparatus 10 and the intermediate apparatus 30.

[Internal configuration of second image forming apparatus]
FIG. 10 is a block diagram showing an internal configuration of the second image forming apparatus 40 of the image forming system 1.
As shown in FIG. 10, the second image forming apparatus 40 includes a print unit 43, an image control board 45, a communication unit 46, and the like.

  Since the print unit 43 has the same configuration as the print unit 23 of the first image forming apparatus 20, the description thereof is omitted.

  The image control board 45 includes a control unit 450, a nonvolatile memory 451, a RAM 452, a DRAM control IC 455, an image memory 456, a decompression IC 457, a writing processing unit 458, and the like.

  The control unit 450 includes a CPU and the like, reads a designated program from the system programs and various application programs stored in the nonvolatile memory 451, and develops the program in the RAM 452. The control unit 250 executes various processes in cooperation with the program expanded in the RAM 452, and centrally controls each unit of the second image forming apparatus 40 and the intermediate apparatus 30.

  The nonvolatile memory 451 stores various processing programs and various data related to image formation. The non-volatile memory 451 stores the types of paper stored in the paper feed device 10, the paper feed unit of the second image forming device 40, the paper feed unit of the first image forming device 20, and each paper feed tray provided in each. I remember information.

The RAM 452 forms a work area for temporarily storing various programs executed by the control unit 450 and various data related to these programs.
The RAM 452 temporarily stores data input from the first image forming apparatus 20 via the communication unit 46.

  The DRAM control IC 455 controls decompression processing of the compressed image data by the decompression IC 457 according to an instruction from the control unit 450 and performs input / output control of image data to the image memory 456.

For example, when job data and compressed image data are input from the communication unit 46, the DRAM control IC 455 stores the job data in the RAM 452 and the compressed image data in the compression memory 456 a of the image memory 456.
In addition, when a print output instruction for compressed image data stored in the compression memory 456a is input from the control unit 450, the DRAM control IC 455 reads the compressed image data from the compression memory 456a, and performs decompression processing by the decompression IC 457. The data is stored in the memory 456b. Further, when a print output instruction for image data stored in the page memory 456b is input, the image data is read from the page memory 456b and output to the write processing unit 458.

  The image memory 456 includes a compression memory 456a and a page memory 456b configured by DRAM. The compression memory 456a is a memory for storing compressed image data, and the page memory 456b is a memory for temporarily storing image data for print output.

  The decompression IC 457 performs decompression processing on the compressed image data.

  The write processing unit 458 generates print image data for image formation based on the image data input from the DRAM control IC 455 and outputs the print image data to the print unit 43.

  The communication unit 46 is a communication interface for connecting to a network to which each device constituting the image forming system 1 is connected. For example, the communication unit 46 communicates with the first image forming apparatus 20 using a NIC or the like, and performs serial communication with the intermediate apparatus 30 and the post-processing apparatus 50.

  The rocking cam drive control unit 471 generates a control signal for controlling the driving of the eccentric cam 384 that rocks the rocking cam 381 (see FIG.) Under the control of the control unit 450, and via the communication unit 46. The control signal is sent to an eccentric cam drive (not shown).

  The curl correction roller drive control unit 472 generates a control signal for controlling the driving of the curl correction roller 314 for correcting the curl of the conveyed paper under the control of the control unit 450, and via the communication unit 46, The control signal is sent to a curl correction roller driving unit (not shown).

  The density sensor signal processing unit 473 receives, via the communication unit 46, a sensor signal that is output as a result of measuring the density of the image formed on the sheet conveyed by the density sensor 319 under the control of the control unit 450. Then, it performs predetermined signal processing and sends it to the control unit 450. The control unit 450 receives the signal sent from the density sensor signal processing unit 473 and adjusts the density of the image formed by the second image forming apparatus 40 based on the measurement result of the density sensor 319. As an example, the gamma curve of the test pattern image is corrected.

  The control unit 450 receives a door opening / closing detection signal output from the door opening / closing detection sensor 30d via the communication unit 46, and controls the driving of the automatic path opening mechanism 32 based on the door opening / closing detection signal.

  Although the swing cam drive control unit 471, the curl correction roller drive control unit 472, and the density sensor signal processing unit 473 have been described separately from the control unit 450, all or part of these functions are controlled by the control unit 450. May have.

(Jam processing)
Next, a jam process performed when a jam occurs in the intermediate device 30 will be described.
FIG. 11 is a flowchart showing jammed paper removal processing in the intermediate apparatus 30.
First, the control unit 450 of the second image forming apparatus 40 determines whether or not a jam has occurred in the image forming system 1 based on the presence or absence of a jam signal. If no jam occurs, this determination process is continued (step S1). ).

  If a jam occurs in the determination process in step S1, the control unit 450 causes the jam to occur in the intermediate device 30 or an upstream device (for example, the first image forming device 20) based on the received jam signal. It is determined whether or not it has occurred (step S2). If a jam occurs in the intermediate device 30 or an upstream device, the control unit 450 immediately stops the conveyance of the paper and sends a message instructing the user to process the jammed paper and the remaining paper. Control to display on the LCD 221 of the operation display unit 22 is performed.

  If the jam is not caused by the intermediate device 30 or the upstream device in the determination process of step S2, the control unit 450 controls the swing cam drive control unit 471 to control the eccentric cam. The operation of 384 is started. Then, the control unit 450 rotates the eccentric cam 384 to swing the swing cam 381 to the left and right, releases the locked state of the first movable guide portion 34 and the second movable guide portion 35, and the first movable guide. The part 34 and the second movable guide part 35 are opened (step S3). As a result, the pressure contact between the registration roller 317 and the conveyance roller 316 is released.

  The control unit 450 conveys the remaining paper in the intermediate device 30 or in the upstream device. Then, residual paper is intensively discharged from the paper transport path 31 after the first movable guide portion 34 and the second movable guide portion 35 of the intermediate device 30 are opened to the storage portion 33. At the same time, the controller 450 returns the swing cam 381 to the home position (step S4).

  Next, the control unit 450 sends a message instructing to process the remaining paper discharged to the storage unit 33 and to return the opened first movable guide unit 34 and second movable guide unit 35 to the LCD 221 of the operation display unit 22. Is displayed (step S5).

  Then, the control unit 450 detects whether or not the first movable guide unit 34 and the second movable guide unit 35 have been returned to the position where the sheet can be guided (guide position) (step S6). When the process of step S6 is completed, the jam process of the intermediate device 30 is terminated.

The detection of whether or not the first movable guide part 34 and the second movable guide part 35 are returned to the guide position is performed by detecting a position of the first movable guide part 34 and the second movable guide part 35 (illustrated). This can be realized by providing (omitted).
The position detection unit is provided in the vicinity of each of the first movable guide unit 34 and the second movable guide unit 35. For example, a position detection switch can be applied as the position detection unit. The fact that the position detection switch has come into contact with the first movable guide portion 34 and the second movable guide portion 35 when the first movable guide portion 34 and the second movable guide portion 35 are returned to the guide position (locked state). It may be detected and a detection signal may be output to the controller 450. Alternatively, a rotation detection sensor (rotary encoder) may be applied to the position detection unit. The rotation detection sensor may detect the rotation angle of the operation units 346 and 356 or the key portions 344a and 354a, and may detect the return of the first movable guide unit 34 and the second movable guide unit 35 from the rotation angle. Good.

  In this way, when a jam occurs, the pressure contact between the registration roller 317 and the conveyance roller 316 is released, so that the paper stopped on the paper conveyance path 31 can be easily removed without breaking. In the above-described example, when a jam occurs in the intermediate device 30 or an upstream device, the conveyance of the paper is immediately stopped and the processing of the jammed paper and the remaining paper is instructed. It is not limited to examples. For example, the remaining paper from the position corresponding to the first movable guide part 34 and the second movable guide part 35 in the paper transport path 31 to the position where the jam on the upstream side is generated is transferred to the first movable guide part 34 and the second movable guide part 34. You may make it open | release the movable guide part 35 to the accommodating part 33. FIG.

In the example of FIG. 11, the first movable guide portion 34 and the second movable guide portion 35 have been described on the assumption that the first movable guide portion 34 and the second movable guide portion 35 are automatically opened. However, the first movable guide portion 34 and the second movable guide portion 35 are manually opened. May be.
For example, the control unit 450 determines whether or not the front door of the intermediate device 30 has been opened from the detection result of the door opening / closing detection sensor 30d. When the front door of the intermediate device 30 is opened, the control unit 450 controls the swing cam drive control unit 471 to rotate the eccentric cam 384 to swing the swing cam 381 left and right. . By this processing, the locked state of the first movable guide portion 34 and the second movable guide portion 35 is released, the first movable guide portion 34 and the second movable guide portion 35 are released, and the pressure contact between the registration roller 317 and the conveyance roller 316 is achieved. Is released. The user removes the jammed paper discharged from the paper transport path 31 and stored in the storage unit 33, and the jam processing ends.

(Registration section on paper transport path)
Next, the registration unit on the paper transport path 31 will be described.
The first and second image forming apparatuses 20 and 40 and the intermediate apparatus 30 of the image forming system 1 each include a registration unit that corrects the skew of the sheet. In the present embodiment, the second image forming apparatus 40 includes a registration roller 433a and a conveyance roller 434a as registration parts, and the intermediate device 30 includes a registration roller 317 and a conveyance roller 316 as registration parts. These registration units correct the skew of the sheet by pushing the sheet from the upstream conveyance roller to the registration roller and forming a loop on the sheet between the registration roller and the conveyance roller.

As shown in FIG. 4, the registration unit of the intermediate device 30 is provided in a sheet conveyance path 31 having a substantially U-shaped curved portion. Since the sheet conveyance path 31 of the registration unit of the intermediate apparatus 30 is curved, it is close to a state in which a loop is formed on the sheet in the sheet conveyance path 31. On the other hand, the sheet conveyance path of the registration unit of the second image forming apparatus 40 is substantially straight. Accordingly, the sheet conveyance path 31 of the registration unit of the intermediate apparatus 30 has a larger curvature than that of the second image forming apparatus 40.
Therefore, in the intermediate device 30, the loop formation amount is made larger than the loop formation amount formed by the resist portion provided in the linear sheet conveyance path of the second image forming apparatus 40. This is because if the amount of loop formation is small in the curved sheet conveyance path 31, the pushing force from the conveyance roller 316 is insufficient, and sufficient skew correction cannot be performed on the sheet.

FIG. 12 is a schematic configuration diagram of a resist unit of the second image forming apparatus 40.
FIG. 13 is a schematic configuration diagram of a registration unit of the intermediate apparatus 30.
As shown in FIG. 12, the registration unit of the second image forming apparatus 40 includes a plate-like lower guide unit 435u and an upper guide unit 435t on the upstream side of the registration roller 433a. Between the lower guide portion 435u and the upper guide portion 435t, a loop forming space 436 for storing the looped paper is formed.
As shown in FIG. 13, the registration unit of the second image forming apparatus 40 includes an inner guide unit 31a and a guide unit 343 of the first movable guide unit main body 341 on the upstream side of the registration roller 433a. Between the inner guide portion 31a and the guide portion 343, a loop forming space 347 for storing the looped paper is formed.

FIG. 14 is a schematic diagram for explaining a loop formed by the resist portion of the second image forming apparatus 40.
FIG. 15 is a schematic diagram for explaining a loop formed by the resist portion of the intermediate apparatus 30.
In this embodiment, the loop formation amount is “the loop length of the paper between the registration roller pair and the conveyance roller pair (registration portion)” and “between the registration roller pair and the conveyance roller pair (registration portion). It is represented by the difference of “paper transport path length”.
Since the registration unit of the intermediate apparatus 30 has a larger loop formation amount of paper than the registration unit of the second image forming apparatus 40, the loop formation amount satisfies the following conditional expression.

ただし、ｌｐ_０、ｄ_０、ｌｐ_１、ｄ_１は以下のとおりである。
ｌｐ_０：第２画像形成装置４０のレジスト部における用紙のループ長
ｄ_０ ：第２画像形成装置４０のレジスト部におけるレジストローラ４３３ａのニップ
部から搬送ローラ４３４ａのニップ部までの用紙搬送路長
ｌｐ_１：中間装置３０のレジスト部における用紙のループ長
ｄ_１ ：第２画像形成装置４０のレジスト部におけるレジストローラ４３３ａのニップ
部から搬送ローラ４３４ａのニップ部までの用紙搬送路長

However, lp ₀ , d ₀ , lp ₁ and d ₁ are as follows.
lp ₀ : Loop length of paper in the registration unit of the second image forming apparatus 40 d ₀ : Nip of the registration roller 433 a in the registration unit of the second image forming apparatus 40
Sheet conveyance path length from the printing unit to the nip part of the conveyance roller 434a lp ₁ : paper loop length in the registration unit of the intermediate apparatus 30 d ₁ : nip of the registration roller 433a in the registration unit of the second image forming apparatus 40
Paper transport path length from the paper to the nip of the transport roller 434a

  As described above, the registration unit of the intermediate apparatus 30 increases the loop formation amount given to the paper more than the registration unit of the downstream image forming apparatus (second image forming apparatus 40). As a result, even in the curved paper transport path 31, it is possible to ensure the skew correction capability for the paper.

  It is more desirable that the loop forming space 347 of the resist unit of the intermediate apparatus 30 is wider than the loop forming space 436 of the resist unit of the second image forming apparatus 40. As a result, the amount of paper fed by the transport roller increases, and the amount of loop formation increases.

  As shown in FIG. 13, the downstream guide portion 343 and the upstream guide portion 353 constituting the registration portion of the intermediate apparatus 30 are divided, and a gap between the downstream guide portion 343 and the inner guide portion 31a is formed. It is more desirable to make it wider than that between the upstream guide portion 353 and the inner guide portion 31a. Thereby, a margin is given to the space for loop formation.

[Modification of image forming system]
FIG. 16 is a schematic diagram illustrating a modification of the overall configuration of the image forming system 1 according to the embodiment of the present disclosure.
In the image forming system 1 illustrated in FIG. 16, an intermediate device 60 is disposed between the first image forming device 20 and the intermediate device 30. In other words, the intermediate device 60 is installed on the downstream side of the first image forming apparatus 20 and the upstream side of the intermediate device 30 in the paper conveyance direction. In the present embodiment, the intermediate apparatus 60 conveys the sheet conveyed from the first image forming apparatus 20 to the intermediate apparatus 30 in accordance with an instruction from the first image forming apparatus 20.

  The intermediate device 60 includes a conveyance path switching unit 61a, a reversing unit 61 having a reversing roller, a stack unit 62 for storing (stacking) sheets on which images have been formed, and the like.

  When it is necessary to reverse the front and back of the sheet conveyed to the intermediate apparatus 30, the sheet conveyed from the first image forming apparatus 20 is conveyed to the reversing unit 61 by the switching operation of the conveyance path switching unit 61a, and the reversing unit The sheet is switched back by the reversing roller 61 and is reversed and conveyed to the intermediate device 30.

  When it is not necessary to reverse the front and back of the paper, the paper transported from the first image forming apparatus 20 is not transported to the reversing unit 61 by the switching operation of the transport path switching unit 61a, and the middle is not reversed. It is conveyed to the device 30.

  In addition, when it is necessary to temporarily store the sheet conveyed from the first image forming apparatus 20, the sheet conveyed from the first image forming apparatus 20 is temporarily stored in the stack unit 62. Note that the intermediate device 60 may include a paper discharge tray for discharging the paper conveyed from the first image forming device 20.

  The embodiment to which the invention made by the present inventor is applied has been described above. However, the present invention is not limited by the description and drawings which form part of the disclosure of the invention according to the above-described embodiments, and various modifications may be made without departing from the spirit of the invention described in the claims. Is possible.

  In the above-described embodiment, the serial tandem image forming system 1 including the first and second image forming apparatuses 20 and 40 has been described. However, a serial tandem image is formed using three or more image forming apparatuses. A forming system may be configured. In this case, among the plurality of image forming apparatuses constituting the image forming system, the image forming apparatus provided on the most upstream side in the sheet conveying direction is set as the main machine, and the image forming apparatus excluding the main machine is set as the sub machine. And

In the above-described embodiment, the intermediate device 30 includes the automatic path opening mechanism 32, and automatically opens the first and second movable guide portions 34 and 35 of the automatic path opening mechanism 32 with the opening of the front door as a trigger. Although the configuration has been described, it may be opened manually.
For example, a handle is provided at a position that is visible to the user when the front door of the intermediate device 30 is opened, and when the user operates the handle, the eccentric cam 384 rotates and the swing cam 381 swings. The second movable guide portions 34 and 35 are unlocked. Alternatively, an operation screen for opening the first and second movable guide units 34 and 35 is displayed on the LCD 221 of the operation display unit 22, and the first and second movable guides are triggered by an operation signal input to the touch panel by the user. You may comprise so that the locked state of the parts 34 and 35 may be cancelled | released.

  Further, in the above-described embodiment, the configuration in which the automatic path opening mechanism 32 includes the first movable guide portion 34 and the second movable guide portion 35 has been described. However, the first movable guide portion 34 and the second movable guide portion 35 are integrated. You may comprise. That is, a driven roller 317b of the registration roller 317 and a driven roller 316b of the conveying roller 316 that is also a loop forming roller are arranged in one movable guide portion, and this movable guide portion is a rotating shaft near the paper conveying path 31. It is set as the structure which can be rotated centering on. As the movable guide portion rotates, the driven roller 317b of the registration roller 317 and the driven roller 316b of the conveyance roller 316 move integrally with the movable guide portion, and the pressure contact between the registration roller 317 and the conveyance roller 316 is released together. Is done.

  DESCRIPTION OF SYMBOLS 1 ... Image forming system 20 ... 1st image forming apparatus 40 ... 2nd image forming apparatus 30, 60 ... Intermediate | middle apparatus, 30A ... Back surface, 30d ... Door opening / closing detection sensor, 31 ... Paper conveyance path, 31a ... Inner guide 31b, 31c ... fixed guide part, 314 ... curl correction roller, 315, 316, 318 ... transport roller, 316a ... drive roller, 316b ... driven roller, 317 ... registration roller, 317a ... drive roller, 317b ... driven roller, 318 ... Conveying roller, 319 ... Concentration sensor, 32 ... Automatic path opening mechanism, 33 ... Storage part, 34 ... First movable guide part, 341 ... First movable guide part body, 341t ... Tip part, 342 ... Rotating shaft part 343: Guide part, 344: Locking member, 344a ... Key part, 345 ... Rotating shaft part, 346 ... Operation 35 ... 2nd movable guide part, 351 ... 2nd movable guide part main body, 351t ... Tip part, 352 ... Turning shaft part, 353 ... Guide part, 354 ... Locking member, 354a ... Key part, 355 ... Turning Shaft portion, 356 ... operation portion, 371, 372 ... fixing pin, 38 ... lock release mechanism, 381 ... swing cam, 381a, 381b ... projection, 382 ... rotating shaft, 383 ... guide hole, 384 ... eccentric cam , 384a ... rotating shaft, 385, 386 ... guide hole, 387, 388 ... guide pin, 436 ... space for loop formation

Claims (9)

A first image forming apparatus disposed on the upstream side in the paper conveyance direction;
A second image forming apparatus disposed on the downstream side in the paper conveyance direction;
Arranged between the first image forming apparatus and the second image forming apparatus, the sheet conveyed from the first image forming apparatus is conveyed to the second image forming apparatus through a curved sheet conveying path. An intermediate device;
A registration unit that is provided in a sheet conveyance path of the second image forming apparatus and that corrects skew of the sheet by forming a loop in the sheet;
A registration unit provided in a paper conveyance path of the intermediate device, and forming a loop on the paper to correct the skew of the paper,
An image forming system in which a loop formation amount for the sheet by the registration unit of the intermediate apparatus is larger than a loop formation amount by the registration unit of the second image forming apparatus. The image forming system according to claim 1, wherein the sheet conveyance path in which the registration unit of the intermediate apparatus is provided has a larger curvature than the sheet conveyance path in which the registration unit of the second image forming apparatus is provided. The loop formation amount includes a loop length of a sheet between a nip portion of a registration roller constituting the registration portion and a nip portion of a loop forming roller arranged upstream thereof, a nip portion of the registration roller, and the nip portion of the registration roller. The ratio of the sheet conveyance path length between the nip part of the registration roller and the nip part of the loop formation roller with respect to the difference in the sheet conveyance path length between the nip part of the loop forming roller and the nip part of the loop forming roller. 3. The image forming system according to 2. The image forming system according to any one of claims 1 to 3, wherein a loop forming space for storing a looped sheet in the registration unit of the intermediate apparatus is larger than a loop forming space in the registration unit of the second image forming apparatus. The sheet conveying path of the intermediate apparatus has a length that prevents the trailing edge of the sheet from entering the first image forming apparatus when the sheet is stopped in the middle of the sheet conveying path after the intermediate apparatus. The image forming system according to claim 1. 5. The image forming apparatus according to claim 1, wherein the intermediate apparatus includes a path opening mechanism that releases pressure contact of the registration rollers disposed in a paper conveyance path of the self apparatus when a jam occurs in the self apparatus. system. The image forming system according to any one of claims 1 to 4, wherein a curl correction unit that corrects curling of the conveyed paper is provided on the paper conveyance path of the intermediate device. The intermediate device includes a density sensor that measures the density of an image formed on the conveyed paper in the vicinity of the paper conveyance path,
The image forming system according to claim 1, wherein the second image forming apparatus adjusts a density of an image formed by the self apparatus based on a measurement result of the density sensor. In an intermediate apparatus that is disposed between the first image forming apparatus and the second image forming apparatus and conveys a sheet conveyed from the first image forming apparatus to the second image forming apparatus through a curved sheet conveying path. ,
A registration unit provided in a paper conveyance path of the intermediate device, which forms a loop on the paper and corrects the skew of the paper;
The amount of loop formation on the paper by the registration unit is greater than the amount of loop formation by the registration unit included in the second image forming apparatus.

Images