JP5880255B2 - Intermediate transport unit and image forming system having the same - Google Patents

Description

  The present invention relates to an intermediate conveyance unit and an image forming system including the intermediate conveyance unit.

  Conventionally, a post-processing device is connected to an image forming apparatus such as a copying machine or a laser beam printer, and punch processing, stapling processing, folding processing, binding processing (saddle stitching, side binding) is performed on a sheet on which an image is formed by the image forming apparatus. ) And a post-processing system such as a bookbinding process are known.

  In this system, an intermediate transport unit may be provided between the image forming apparatus and the post-processing apparatus in order to collectively transport a plurality of sheets from the image forming apparatus to the post-processing apparatus (for example, Patent Document 1). reference). The intermediate transport unit is loaded with sheets of images formed from the image forming apparatus, sequentially stacks the loaded sheets in the stacking unit, stacks a predetermined number of sheets, and discharges them to the post-processing apparatus.

  In the conventional intermediate transport unit disclosed in Patent Document 1, the loaded paper is transported to the stacking unit side by a transport roller disposed above the stacking unit, and is freely dropped and stacked on the stacking unit. Therefore, depending on the paper type and size of the paper to be carried in, it jumps at the bottom of the stacking unit, returns to the carry-in side, and is jammed or collapsed by being caught by the conveyance roller. There is a risk of doing.

  On the other hand, in Patent Document 2, a jogger stopper that moves up and down in accordance with the falling speed of the paper is provided on the side where the free-falling paper is accommodated, and the shock is reduced by the jogger stopper when receiving the paper. A reversing device that prevents rebounding is disclosed.

JP 2008-1115010 A JP-A-6-247603

  However, when the conventional reversing device is applied to the image forming apparatus, it is necessary to move up and down the jogger stopper that receives the paper every time the paper that is carried in is collected.

  For this reason, when the image forming apparatus including the reversing device is used in the field of production and printing (PP field, commercial printing, mass printing in a company), productivity is reduced, and printing processing is accelerated. It is not suitable for the user and cannot satisfy the user's request.

  SUMMARY OF THE INVENTION The present invention has been made to solve the above-described problems. An intermediate transport unit that can be efficiently integrated without causing a decrease in productivity even when mass printing is performed, and an image forming system including the intermediate transport unit The purpose is to provide.

An intermediate transport unit according to the present invention is disposed between an image forming unit and a post-processing unit, and can receive a sheet discharged from the image forming unit and collectively discharge a plurality of sheets to the post-processing unit. A stacking unit that stacks a plurality of sheets in a vertical direction, a transport roller that is provided above the stacking unit and is spaced apart from the stacking unit, and discharges the sheet to the stacking unit so as to fall into the stacking unit; A closed position that is disposed between the transport roller and the stacking unit, closes a path of a sheet that moves from the transport roller to the stacking unit, and guides the sheet that moves along the path at a position along the path. An assist guide that can be moved to an open position; and a control unit that controls movement of the assist guide, wherein the control unit is configured to move the assist guide and the sheet to the transport roller. From being discharge by error to return to the bottom by bouncing the transport rollers of the stacking unit, the move from the open position to the closed position, to discharge the paper from the conveying roller to the stacking unit side timing Prior to this, a configuration is adopted in which movement of the assist guide from the open position to the closed position is started .

An image forming system according to the present invention includes an image forming unit that forms an image on a sheet and discharges the sheet, a post-processing unit that performs post-processing on the image-formed sheet, the image forming unit, and the post-processing unit. An intermediate transport unit that receives the paper discharged from the image forming unit and discharges the paper to the post-processing unit at a time, and the intermediate transport unit discharges the plurality of paper in the vertical direction. A stacking unit that stacks, a transport roller that is spaced apart above the stacking unit and that discharges paper to the stacking unit so as to fall into the stacking unit, and a space between the transport roller and the stacking unit A closed position that closes a path of paper that moves from the transport roller to the stacking unit, and an open position that guides the paper that moves along the path and moves along the path. A movable assist guide; and a control unit that controls movement of the assist guide, wherein the control unit moves the assist guide at the bottom of the stacking unit after the paper is discharged by the transport roller. Before the sheet is ejected from the open position to the closed position until it bounces back to the transport roller, and the paper is discharged from the transport roller to the stacking unit, the assist guide is moved from the open position to the close position. The structure which starts the movement to a closed position is taken .

  According to the present invention, the assist guide moves from the open position for guiding the paper on the path to the closed position for closing the path after the paper is discharged by the transport roller and then bounces at the stacking unit and returns to the transport roller. Therefore, even when the paper bounces back at the bottom of the stacking unit (bounces back), it does not reach the transport roller. As a result, it is not necessary to operate the stacking unit each time the sheets are stacked in order to prevent the paper from rebounding, and even when performing large-scale printing, the stacking is performed efficiently and without skewing without reducing productivity. it can.

1 is a diagram illustrating an image forming system having an intermediate conveyance unit according to an embodiment of the present invention. 1 is a functional block diagram showing a main configuration of an image forming system having an intermediate conveyance unit according to an embodiment of the present invention. Schematic diagram showing the main part of the intermediate transport unit Front view of assist guide Side view of assist guide Diagram showing the alignment section in the paper width direction Diagram showing the operation of the assist guide when loading paper Diagram showing the operation of the assist guide when loading paper Diagram showing the operation of the assist guide when loading paper Diagram showing the operation of the assist guide when loading paper The figure which shows the state which accumulated the paper in the accumulation part Diagram showing the operation of the assist guide when ejecting paper Diagram showing alignment operation when paper is ejected

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

<Overall configuration of image forming system>
FIG. 1 shows an image forming system 10 having an intermediate conveyance unit according to an embodiment of the present invention.

  The image forming system 10 includes an image forming unit G, an intermediate transport unit (Relay Unit) RU, and a post-processing unit (Finisher) F as a sheet processing apparatus. The image forming unit G prints an image on a sheet, and the post-processing unit F performs post-processing on the printed sheet conveyed via the intermediate conveyance unit RU.

  The image forming unit G includes a touch panel 211, an ADF (Auto Document Feeder) 221, a scanner 222, a printing unit 23, and a paper feeding unit 24. The ADF 221 conveys the set original to the scanner 222, and the scanner 222 scans the conveyed original. The printing unit 23 includes an image forming unit 231 and a fixing unit 232. The image forming unit 231 forms an image with toner during printing processing, and transfers the toner image onto a sheet conveyed from the paper feeding unit 24. The sheet on which the toner image is transferred by the image forming unit 231 is fixed by the fixing unit 232. After the fixing process, the sheet is conveyed to the intermediate conveyance unit RU.

  The intermediate transport unit RU is provided between the image forming unit G and the post-processing unit F. The intermediate transport unit RU receives sheets printed by the image forming unit G one by one and transports them as they are to the post-processing unit F, or stacks the printed sheets in the stacking unit 34 (see FIG. 3). Collected sheets are collected and conveyed to the post-processing unit F in units of a plurality of sheets.

  The post-processing unit F includes a post-processing unit 43. The post-processing unit 43 performs post-processing on the paper transported from the intermediate transport unit RU. Examples of the post-processing include at least one of a stapling process, a punching process, a folding process, and a gluing bookbinding process. The post-processed paper is discharged to a paper discharge tray 45. The post-processing unit F has a transport path that reaches the paper discharge tray 45 without going through the post-processing unit 43, and the paper that is carried in from the intermediate transport unit RU is passed through the transport path without performing post-processing. Paper can also be discharged.

<Functional blocks of image forming system>
FIG. 2 is a functional block diagram showing a main configuration of the image forming system 10 having the intermediate conveyance unit according to the embodiment of the present invention.

  As shown in FIG. 2, the image forming unit G includes an operation unit 21, a reading unit 22, a printing unit 23, a control unit 25, a display unit 27, a communication unit 28, and a storage unit 29.

  The operation unit 21 includes a touch panel 211 and operation keys. The operation unit 21 generates an operation signal corresponding to the input operation by the user and outputs the operation signal to the control unit 25.

  The reading unit 22 optically scans the document conveyed by the ADF 221 with the scanner 222 to generate image data.

  The control unit 25 includes a CPU (Central Processing Unit), a RAM (Random Access Memory), and the like. The control unit 25 performs various calculations in cooperation with various processing programs stored in the storage unit 29 and centrally controls each unit of the image forming unit G.

  The control unit 25 creates job information for printing and post-processing. The job information is control information including instructions for printing conditions, post-processing conditions, and paper conveyance conditions according to these conditions.

  The display unit 27 displays an operation screen and a processing result on the touch panel 211 under the control of the control unit 25.

  The communication unit 28 includes a communication interface, and communicates with the intermediate transport unit RU and the post-processing unit F. For example, the communication unit 28 transmits job information to the intermediate transport unit RU and the post-processing unit F.

  The storage unit 29 stores various processing programs, parameters necessary for processing, setting data, and the like. The storage unit 29 stores image data. As the storage unit 29, a hard disk or a DRAM (Dynamic RAM) can be used.

  The intermediate transport unit RU includes a transport unit 30, a communication unit 31, a storage unit 32, a control unit 33, an FD (Feed Direction) matching unit 35, a CD (Cross Direction) matching unit 36, and a sensor group 330 (paper passage sensor 333). ).

  The transport unit 30 is driven and controlled by the control unit 33, receives the paper transported from the control unit image forming unit G, transports the sheets one by one, or collects a plurality of sheets using the stacking unit 34 (see FIG. 3). Or discharged to an aftertreatment unit.

  The communication unit 31 communicates with the image forming unit G and the post-processing unit F, and outputs the communicated information to the control unit 33. For example, job information is received from the image forming unit G and output to the control unit 33. The storage unit 32 stores data such as programs used by the control unit 33. For example, the storage unit 32 stores a control table used for movement control of an assist guide 38 (see FIG. 3) described later. In the control table, the movement amount and movement timing of the assist guide 38 are set according to the paper type, size, and the like of the paper conveyed to the intermediate conveyance unit RU. The storage unit 32 stores a control table used for movement control of the FD matching unit 35 and drive control of the CD matching unit 36.

  The control unit 33 has the same configuration as the control unit 25 of the image forming unit G, and centrally controls each unit of the intermediate transport unit RU. That is, the control unit 33 analyzes the job information transmitted from the image forming unit G using the communication unit 31 and the storage unit 32, and reads the sheet conveyance conditions.

  The control unit 33 controls the conveyance of the paper loaded from the image forming unit G through the conveyance unit 30 according to the read conveyance conditions. For example, the control unit 33 advances the paper carried from the image forming unit G straight as it is to the post-processing unit F, or collects a plurality of sheets by the accumulating unit 34 (see FIG. 3). Or conveyed to the processing unit F. In addition, the control unit 33 moves the assist guide 38 (see FIG. 3) in the intermediate transport unit RU and switches the paper transport path based on information from the communication unit 31, the storage unit 32, and the sensor group 330.

  In particular, the control unit 33 controls the movement of the assist guide 38 (see FIG. 3) based on the detection timing signal from the paper passage sensor 333. The control unit 33 closes the assist guide 38 (see FIG. 3) from the open position until the sheet is ejected by the transport roller R2 and then bounced by the stacking unit 34 to return to the transport roller R2 (see FIG. 3). Move to position.

  The FD alignment unit 35 is driven and controlled by the control unit 33 and aligns, that is, aligns, the end portions in the paper transport direction (Feed Direction). Further, the CD alignment unit 36 is driven and controlled by the control unit 33, and aligns, that is, aligns, ends in the width direction (Cross Direction) which is a direction perpendicular to the transport direction. The specific configurations of the FD matching unit 35 and the CD matching unit 36 will be described later with reference to FIG.

  The sensor group 330 outputs necessary information to the control unit 33 when the control unit 33 performs centralized control of each unit in the intermediate transport unit RU. The sensor group 333 includes a CD (Cross Direction) HP (Home Position) sensor (not shown), an FD (Feed Direction) HP (Home Position) sensor (not shown), and the like in addition to the paper passage sensor 330.

  The paper passage sensor (detection unit) 333 is provided on the upstream side of the transport roller R2 in the transport path Y, detects the passage of the paper moving on the transport path Y, and outputs the detected result to the control unit 33. Specifically, the paper passage sensor 333 detects passage of the rear end of the paper, and for example, a photo sensor or the like is applied. The paper passage sensor 333 detects the paper before the paper is discharged from the transport roller R2.

  The post-processing unit F includes a communication unit 41, a storage unit 42, a post-processing unit 43, and a control unit 44. The communication unit 41 communicates with the image forming unit G and the intermediate transport unit RU and outputs the information to the control unit 44. The storage unit 42 stores data such as a program used by the control unit 44.

  The control unit 44 controls the post-processing unit F so as to perform control according to information set by the image forming unit G together with the intermediate transport unit RU. Here, the control unit 44 has the same configuration as the control unit 25 of the image forming unit G, and centrally controls each unit of the post-processing unit F. Specifically, the control unit 44 analyzes the job information transmitted from the image forming unit G using the communication unit 41 and the storage unit 42, and reads the instructed post-processing condition. The control unit 44 causes the post-processing unit 43 to perform post-processing based on the read post-processing conditions.

<Configuration of main part of intermediate transport unit RU>
FIG. 3 is a schematic diagram showing a main part of the intermediate transport unit RU.

  As shown in FIG. 3, the intermediate transport unit RU has paper transport paths X and Y. In the conveyance path X, the sheets carried one by one from the image forming unit G are advanced in the horizontal direction via the carry-in port, and discharged to the post-processing unit F without going through the stacking unit 34. Further, in the transport path Y, the sheets carried one by one from the image forming unit G through the carry-in entrance are transported to the stacking unit 34 while the sheets are advanced obliquely downward, and are stacked in the vertical direction by the stacking unit 34. . A plurality of sheets stacked in the stacking unit 34 are collected, advanced obliquely upward from the stacking unit 34, and discharged to the post-processing unit F. Note that the front and back of the paper that has passed through the transport path Y are reversed.

  The intermediate transport unit RU includes a transport unit 30 having transport rollers R1 to R4 including a pair of rollers, a stacking unit 34, an FD alignment unit 35, a CD alignment unit 36, a switching guide 37, and an assist guide 38. And an opposing guide 39.

  Each of the transport rollers R1 to R4 is controlled by the control unit 33 (see FIG. 2), and is rotated and driven via a motor (not shown) to sandwich and transport the paper.

  The transport roller R1 is disposed near the paper carry-in entrance, and the transport roller R4 is disposed near the paper discharge port. Here, the transport roller R1 is disposed on the upstream side of the branch portion of the transport path X and the transport path Y. The transport roller R1 transports the nipped paper to one side of the transport path X and the transport path Y.

  The transport roller R4 is disposed downstream from the joining portion of the transport path X and the transport path Y. The transport roller R4 discharges the paper that is transported by the transport roller R1 or the transport roller R3 downstream, and transports the paper to the post-processing unit F in this case.

  The transport roller R2 is paired with the driven roller R21 and is disposed on the carry-in side path of the transport path Y. The transport roller R2 sandwiches the paper that is transported to the transport path Y side by the transport roller R1 and transports the paper to the stacking unit 34 disposed below.

  At this time, the transport roller R2 is rotationally driven in the loading direction side to the stacking unit 34 and discharges the paper. The paper discharged from the transport roller R2 falls freely and is collected in the stacking unit 34. That is, the transport roller R <b> 2 is spaced apart above the stacking unit 34 and discharges paper to the stacking unit 34 side so as to fall into the stacking unit 34. The driven roller R21 is longer in the axial direction than the transport roller R2. That is, both end portions of the driven roller R21 protrude in the axial direction from both end portions of the transport roller R2. Thereby, when the sheet is discharged from the transport roller R2, the trailing edge of the sheet is not easily caught.

  The transport roller R3 is disposed on the paper discharge side path of the transport path Y. The transport roller R3 sandwiches and transports the paper discharged to the post-processing unit F via the stacking unit 34.

  Further, the transport roller R3 rotates (reversely rotates) in the direction opposite to the paper discharge direction, so that, together with the stopper 351, the end portions (rear end, front end) that are separated in the transport direction in the paper stacked on the stacking unit 34. Align.

  A switching guide 37 is disposed on the downstream side of the transport roller R1 and at the branch point of the two transport paths X and Y.

  The switching guide 37 is rotated by a control unit 33 via a drive unit such as a motor (not shown), and the rotation path opens and closes the entrance of the conveyance path Y. The switching guide 37 moves to an open position indicated by a solid line when conveying a sheet to the conveyance path Y, and moves to a closed position indicated by a dotted line to convey the sheet when conveying a sheet to the conveyance path X. Switch. The drive unit that rotates the switching guide is not limited to a motor, and may be a solenoid that is driven and controlled by the control unit 33, for example.

  The assist guide 38 is disposed between the transport roller R2 and the stacking unit 34, guides the carry-in of paper from the transport roller R2 to the stacking unit 34 on the transport path Y, and on the transport path Y, the stacking unit. Guides the conveyance of the sheet from 34 to the conveyance roller R3. Further, the assist guide 38 prevents the paper from being bounced at the bottom (here, the stopper 351) of the stacking unit 34 and returned to the transporting roller R2 side when paper is carried into the stacking unit 34 from the transport roller R2.

  That is, the assist guide 38 is a closed position that closes the path of the paper that moves from the transport roller R2 to the stacking unit 34 (the entrance path Y1 to the stacking unit 34 in the transport path Y), and a position along the entrance path Y1. It moves to the open position for guiding the paper that moves Y1.

  The assist guide 38 is disposed below the transport roller R2 on the transport path Y. The assist guide 38 is formed by a plate-like member that extends in the vertical direction.

  FIG. 4 is a front view of the assist guide 38, and FIG. 5 is a side view of the assist guide 38.

  In the assist guide 38, a plurality of protrusions 381 are provided on the surface facing the sheet. These protrusions 381 are long in the paper transport direction and are arranged in parallel in the paper width direction (direction perpendicular to the paper transport direction).

  The assist guide 38 protects the paper by bringing the protrusion 381 into contact with the paper when guiding, reducing the contact area with the paper without impairing the guide function.

  As shown in FIG. 3, the assist guide 38 configured as described above is pivotally mounted by driving a motor 382 around the lower base end 38 a side.

  As a result, the assist guide 38 is displaced between an open position indicated by a solid line and a closed position indicated by a dotted line, and can open and close an approach path Y1 as a transport path in the transport direction from the transport roller R2 to the stacking unit 34. In the open position, the path from the transport roller R2 to the stacking unit 34 in the transport path Y is opened and opened. The movement of the assist guide 38 is controlled by the control unit 33.

  As shown in FIG. 3, when the assist guide 38 is on the open position side, it functions as a guide in the loading direction. The paper that has passed through the transport roller R2 is guided by the assist guide 38 and transported to the stacking unit 34.

  The assist guide 38 is displaced from the open position side to the closed position after the sheet is discharged from the transport roller R2 until it jumps at the bottom (stopper 351) of the stacking unit 34 and returns to the transport roller R2 side. As a result, the assist guide 38 closes, that is, closes, the transport path Y (entrance path Y1) between the transport roller R2 and the stacking unit 34.

  In this closed state, a gap (for example, about 2 mm) through which the sheet can pass is formed between the tip 38b of the assist guide 38 and the opposing guide 39. Therefore, when the assist guide 38 is located at the closed position, the approach path Y1 is closed, and the assist guide 38 is in contact with the sheet discharged from the stacking unit 34 and serves as a guide in the discharge direction.

  Here, the assist guide 38, together with the opposing guide 39 disposed on the opposite side of the assist guide 38, guides a sheet of paper or a plurality of sheets pushed out from the stacking unit 34 in the vertical direction, and conveys the sheet in the discharge direction. Let Here, the opposing guide 39 is arranged in the vertical direction. Further, the tip end portion 38 b of the assist guide 38 in the closed position is close to the upper end of the opposing guide 39. Note that the assist guide 38 in the closed position may be slightly inclined rather than parallel to the opposing guide 39. The facing guide 39 is formed at the tip of the support plate portion 343 of the stacking portion 34.

  The stacking unit 34 extends in the vertical direction, has a support plate unit 343 having a support surface 3431 for stacking sheets, and an opposing support unit 341 having a support surface 3411 facing the support surface 3431 on the carry-in side. Have The support plate portion 343 and the opposing support portion 341 are fixed to a stacking frame (not shown), and the stacking portion 34 forms both side surfaces of a region where sheets are stacked. The support surface 3431 is flush with the guide surface of the opposing guide 39.

  The support surfaces 3431 and 3411 are parallel to each other. The length of the support surface 3411 in the transport direction is substantially the same as the length of the paper in the transport direction. The support surface 3411 is provided with a plurality of protrusions (not shown) extending in the transport direction in parallel in the paper width direction. Even if the protrusions (not shown) come into contact with the paper during the paper guide, the contact area with the paper is reduced without impairing the guide function, thereby protecting the paper. In addition, an opposing guide 39 having a guide surface that is flush with the support surface 3431 included in the support plate portion 343 is provided on the upper portion of the support plate portion 343.

  The bottom of the stacking unit 34 includes a stopper 351 that is movable on the support surface 3431 in the vertical direction (conveying direction). The stopper 351 is formed on the frame portion 35 a of the FD matching portion 35. The stopper 351 stops the conveyance of the paper that has entered the stacking unit 34 and supports the leading edge of the paper located below.

  The FD aligning unit 35 and the CD aligning unit 36 are provided adjacent to the stacking unit 34 and align end portions of one or a plurality of sheets stacked in the stacking unit 34.

  The FD alignment unit 35 is disposed in parallel with the support surface 3431 of the stacking unit 34 and has a U-shaped side view attached to a guide bar 354 extending in the vertical direction (here, the vertical direction) so as to be movable up and down. It has a frame part 35a. The guide rod 354 is fixed to the lower end portion of the support plate portion 343 and the bracket 345 fixed to the opposing guide 39. Thereby, the guide rod 354 is fixed to the support plate portion 343.

  The frame part 35 a is fixed to a pulley of the motor 353 and an endless belt 356 wound around the pulley 355 via a support part 352. The pulley 355 is fixed to the opposing guide 39 via a bracket 345, and the motor 353 is disposed to face the lower end portion of the support plate portion 343. With this configuration, the endless belt 356 is disposed along the extending direction of the guide rod 354. When the motor 353 is driven by the control unit 33, the endless belt 356 rotates, and the frame unit 35a moves up and down along the guide rod 354 accordingly.

  A stopper 351 is formed on the lower side of the frame portion 35a. The stopper 351 protrudes toward the support surface 3431 through a guide opening formed on the support surface 3431 so as to extend vertically.

  In the stopper 351, a receiving plate portion 3513 is attached to the inside of the accumulation portion 34, that is, on a base 3511 that is a portion that can freely move in the vertical direction between the support surfaces 3431 and 3411 via a cushion material (buffer material such as rubber) 3512. It has been. The receiving plate portion 3513 receives the paper entering the stacking portion 34 through the cushion material 3512.

  Specifically, the stopper 351 is discharged from the transport roller R2 and freely falls to receive the sheet that enters the stacking unit 34, that is, between the support surfaces 3431 and 3411, on the receiving plate unit 3513 on the cushion material 3512. Receive at. As a result, when the sheets are stacked on the stacking unit 34, the stopper 351 absorbs the sheet discharged from the transport roller R <b> 2 and collides with the cushion material 3512, and the sheet directly collides with the stopper 351. The generated sound can be reduced. As a result, the stopper 351 achieves noise reduction during the accumulation. In addition, the receiving plate part 3513 is comprised by the SUS board etc., for example.

  The CD aligning portion 36 is attached to the opposing support portion 341.

  As shown in FIG. 6, the CD alignment unit 36 includes a pair of left and right arm-shaped alignment members 361 and 362. The alignment members 361 and 362 are arranged so as to sandwich the paper in the support surfaces 3431 and 3411, that is, the paper in the stacking unit 34 in the width direction.

  The left alignment member 361 is fixed to the pin 363, the right alignment member 362 is fixed to the pin 364, and the pins 363 and 364 are fixed to one rotating surface and the other rotating surface of the rotating belt 365, respectively. The As the belt 365 is rotated by driving the motor 366, the left and right alignment members 361 and 362 move in the opposite directions. That is, by repeatedly moving the two alignment members 361 and 362 away from each other, the edge of the sheet S in the width direction is pressed a plurality of times to align the ends of the sheet in the width direction.

  Next, a series of operations in which the intermediate transport unit RU collects and discharges a plurality of sheets (here, two sheets) will be described with reference to FIG.

  Before the conveyance of the sheet, the stopper 351 of the FD alignment unit 35 is at the initial position V0.

  When the first sheet is carried in from the image forming unit G, the conveyance guide 37 is moved to the open position (solid line position in FIG. 3) under the control of the control unit 33. At this time, the assist guide 38 is located at the open position (solid line position in FIG. 3).

  The sheet is transported by transport rollers R1 and R2 and a driven roller R21, and is guided by a switching guide 37 and an assist guide 38 as shown in FIG.

  As described above, when the paper S is discharged from the transport roller R2 to the stacking unit 34 side, the assist guide 38 is controlled by the control unit 33 to be near the entrance-side transport path Y (entry path Y1). Guide the paper while waiting in position.

  Specifically, the assist guide 38 waits at the open position separated by a distance M from the position L through which the paper passes on the transport path Y from the transport roller R2 to the stacking unit 34, and then from the transport roller R2 to the stacking unit 34 side. The sheet S to be conveyed is guided. As described above, the assist guide 38 is positioned at the open position deviated from the transport path Y of the paper S by M, and guides the paper S passing through the entrance-side transport path Y, specifically, the entrance path Y1. Yes. For this reason, even when the paper S is, for example, a soft paper type, there is no resistance when dropped.

  When the paper S is discharged from the transport roller R2, that is, when the rear end SB of the paper S is released from the holding state of the transport roller R2, the assist guide 38 is controlled by the control unit 33 (see FIG. 2). It starts moving to the closed position. In other words, the assist guide 38 starts to move from the open position to the closed position before the timing at which the sheet S is discharged from the transport roller R2 to the stacking unit 34 side by the control unit 33 (see FIG. 2).

  Thereby, as shown in FIG. 8, when the trailing edge SB of the sheet S has come out of the transport roller R2 and the driven roller R21, the assist guide 38 moves the transport roller R2 in the direction of the arrow D1 toward the closed position. The sheet S that has passed through is contacted. As a result, the rear end of the sheet S is pressed toward the closed position and falls and easily falls within the stacking unit 34.

  The timing of starting the movement of the assist guide 38 is set based on the detection result of the paper passage sensor 333, and the timing at which the rear end SB of the paper S is removed (separated) from the transport roller R2 is controlled using this setting. The unit 33 controls.

  As for the timing of starting the movement of the assist guide 38, first, the paper is discharged from the transport roller R2 after a predetermined time (mmSEC) at a preset speed with reference to the paper passage timing passing through the sensor position of the paper passage sensor 333. Set the paper discharge timing. This paper discharge timing is a timing at which the trailing edge of the paper comes out from the transport roller R2. The time taken for the paper ejected at this paper ejection timing to bounce off the stopper 351 of the stacking unit 34 and reach the transport roller R2 is the distance from the transport roller R2 to the stopper 351, and the movement of the preset paper. Set based on speed. Based on these, the controller 33 preliminarily arranges the assist guide 38 so as to be positioned on the path of the paper that bounces back to the transport roller R2 until the paper discharged at the paper discharge timing reaches the transport roller R2. The timing for starting the movement of the assist guide 38 that moves at the set moving speed is set.

  The paper discharge timing, the movement start timing of the assist guide 38, the movement speed of the assist guide 38, and the peripheral speed (paper discharge speed) of the transport roller R2 are controlled according to the paper basis weight, size (for example, paper width 160 mm), and paper type. It is stored in the storage unit 32 as a table.

  Here, it is set as the movement start timing when the sheets to be stacked are predetermined sheets that are paper types having a size equal to or smaller than a predetermined size (predetermined width). In other words, a movement start timing is set for moving the assist guide 38 from the open position to the closed position until the predetermined sheet with the trailing edge coming out of the transport roller R2 bounces back at the bottom (stopper 351) of the stacking section 34. ing.

  The control unit 33 uses the control table stored in the storage unit 32 of the intermediate transport unit RU to start moving the assist guide 38 at a predetermined moving speed and at a predetermined timing. As a result, the assist guide 38 moves to the closed position side while touching the paper S coming out of the transport roller R2.

  Here, at the paper discharge timing set based on the timing at which the paper has passed through the sensor position of the paper passage sensor 333 (see FIG. 8), the leading end 38b of the moving assist guide 38 touches the paper. The timing for starting the movement is set. For this reason, before the trailing edge of the paper passes through the transport roller R2, the control unit 33 causes the motor 382 that drives the assist guide 38 to also move out of the paper from the transport roller R2, so that the assist guide 38 starts to move. Excitation is started.

  As a result, as shown in FIG. 9, the assist guide 38 causes the paper S discharged from the transport roller R2 to freely fall and hit the stopper 351 (specifically, the receiving plate portion 3513) which is the bottom of the stacking portion 34. Before it bounces, it will start moving to the closed position.

  Accordingly, the assist guide 38 is transported to the transport roller R2 side before the paper S discharged from the transport roller R2 falls freely and hits the stopper 351 which is the bottom of the stacking unit 34 and returns to the transport roller R2 side. Move to a position where route Y (entrance route Y1) is closed.

  As a result, as shown in FIG. 10, even when the sheet S bounces because the leading end SF of the dropped sheet S abuts against the stopper 351 (specifically, the receiving plate portion 3513), the bounced sheet S is conveyed. It does not return to the roller R2 side. Further, since the assist guide 38 has moved to the closed position, the bounced paper S is guided to the carry-out side.

  Note that the stopper 351 includes a base 3511, a cushion material 3512 on the base 3511, and a receiving plate portion 3513 on the cushion material 3512. Therefore, the paper that bounces off at the stopper 351 is actually bounced off at the receiving plate portion 3513 of the stopper 351 via the cushion material 3512. As a result, the paper can be more easily bounced, but the assist guide 38 prevents the bounce back to the carry-in side of the stacking unit 34.

  Then, the paper S that has been splashed by the stopper 351 that is the bottom of the stacking unit 34 returns to the stacking unit 34 again. Then, the front end SF of the paper S abuts against the stopper 351, and the progress is stopped.

  When the sheet S reaches the stopper 351 due to the front end SF abutting against the stopper 351 in this manner, the stopper 351 is raised by an instruction from the control unit 33 and moves from the initial position V0 shown in FIG. 3 to the position V1.

  Next, in order to guide the loaded paper to the stacking unit 34 side, the control unit 33 moves the assist guide 38 to the open position.

  When the second sheet is carried in from the image forming unit G, the control unit 33 causes the switching guide 37 and the assist guide 38 to guide the second sheet as in the case of the first sheet S. Transport to the stacking unit 34. As with the first sheet, the assist guide 38 starts to move toward the closed position when it has come out of the transport roller R2, so that the second sheet away from the transport roller R2 is moved to the assist guide 38. By this, it will be pushed into the opposing guide 39 side. On the other hand, in the stacking unit 34, the trailing edge SB of the first sheet is higher than the lower end of the roller located on the left side of the pair of transport rollers R2 shown in FIG. In the side position.

  As a result, when the assist guide 38 moves to the closed position side, the second sheet is pushed into the stacking unit 34, and the leading edge SF of the second sheet is the trailing edge of the first sheet S. Without being collided, it is guided by the paper S and proceeds through the stacking unit 34.

  As a result, the second sheet is stacked so as to be positioned on the back side of the first sheet without jumping by the stopper 351 and returning to the transport roller R2. Further, since the assist guide 38 has moved to the closed position side, the sheets accumulated in the accumulation unit 34 can be guided to the carry-out side.

  When the second sheet after entering the stacking unit 34 and hitting the stopper 351 (specifically, the receiving plate unit 3513) stops at the stopper 351 and fits in the stacking unit 34, the stopper 351 is controlled by the control unit. As shown in FIG. 11, the vehicle moves down from the position V1 to the initial position V0. As described above, a plurality of sheets S and SS are stacked on the stacking unit 34 in a stacked state.

  Next, when the sheets S and SS collected in the collecting unit 34 are discharged together, the stopper 351 moves up and moves from the initial position V0 to the position V2. As the stopper 351 rises, the lower ends of the stacked sheets S and SS (specifically, the leading ends SF of both sheets S and SS) are pushed up, and the sheets S and SS advance vertically upward as shown in FIG. . As shown in FIG. 12, the sheets S and SS that are traveling vertically upward are guided by the assist guide 38 and the opposing guide 39.

  The position V2 is a position where the distance between the position V2 and the transport roller R3 is equal to the length in the transport direction of the paper, and the transport roller R3 is a position where the length of the paper S in the transport direction is aligned with the stopper 351. is there.

  That is, when the stopper 351 (specifically, the receiving plate portion 3513) moves to the position V2, as shown in FIG. 13, the rear end (upper end in the figure) SB of the paper S guided by the assist guide 38 and the opposing guide 39. Reaches the transport roller R3. At this time, the transport roller R3 rotates in the direction opposite to that during normal transport based on an instruction from the control unit 33, and the rear ends SB of the plurality of sheets S at the nip portion with the carry-out driven roller R31. To match. The reverse rotation of the transport roller R3 is to prevent the rear end SB (upper end in the drawing) of the sheets S and SS from entering between the transport roller R3 and the carry-out driven roller R31. Thereby, the conveyance roller R3 is aligned with the stoppers 351 in the conveyance direction with respect to the overlapping sheets S and SS.

  Note that the stop position at the upper end of the two sheets S and SS (actually, the trailing end SB of the sheet) in the stacking unit 34 is on the downstream side in the transport direction from the sandwiching position of the transport roller R3 and the unloading driven roller R31. At this time, the CD alignment unit 36 moves the alignment members 361 and 362 by a motor 366 (see FIG. 6) driven by the control unit 33 at the same time or after the alignment operation in the transport direction, and the width direction of the sheet S Align in

  Thereafter, when the transport roller R3 rotates its rotational direction back to the normal rotational direction, the sheets S and SS with the rear end (upper end in the figure) SB aligned are collectively transported in the paper discharge direction. That is, the overlapping sheets (here, two sheets) S and SS are transported by the transport roller R3 in a state where the length and width are aligned. Then, the paper is nipped by the transport roller R4 (see FIG. 3) and discharged from the intermediate transport unit RU to the post-processing unit F.

  On the other hand, when a predetermined time has elapsed after the paper discharge from the stacking unit 34 is started, the assist guide 38 finishes the guide, moves to the open position, and returns to the position before the guide in the paper discharge direction.

  As described above, according to the intermediate transport unit RU of the present embodiment, the control unit 33 causes the assist guide 38 (see FIG. 3) via the motor 382 and the stacking unit 34 after the paper is discharged by the transport roller R2. Is moved from the open position to the closed position until it returns to the transport roller R2 (see FIG. 3). Specifically, the control unit 33 uses the detection timing of the paper passage sensor 333 to move the rear end (rear end in the transport direction) of the paper discharged from the transport roller R2 from the transport roller R2 (see FIG. 3). Set the paper discharge timing when leaving.

  The control unit 33 controls the movement of the assist guide 38 (see FIG. 3) using the set paper discharge timing, and the assist guide 38 is moved to the paper S when the trailing edge of the paper S is removed from the transport roller R2. The assist guide 38 is moved so as to come into contact. That is, the control unit 33 sets the time until the paper ejected from the transport roller R2 bounces back to the transport roller based on the paper detection timing of the paper passage sensor 333. The controller 33 moves the assist guide 38 to the closed position via the motor 382 within the set time.

  Thus, even when the paper S bounces back at the stacking unit 34 (bounces back), the paper S does not reach the transport roller R2 that has ejected the paper S. Therefore, unlike the conventional case, it is not necessary to operate the stacking unit side every time the sheets are stacked in order to prevent the sheet S from rebounding, and even when performing a large amount of printing, the skew can be efficiently performed without reducing the productivity. It can be accumulated without letting.

  The assist guide 38 is a plate-like member provided with a plurality of protrusions 381 on the surface facing the sheet, and the plurality of protrusions 381 are arranged in parallel in the sheet width direction. The contact area can be reduced by using the protrusions 381 instead of the entire sheet, thereby protecting the sheet.

  Since the ridge portion 381 has a length corresponding to the length in the sheet conveyance direction, the guide function can be sufficiently ensured even if the contact portion is the ridge portion 381 alone.

  The image forming system 10 according to the present embodiment is an example of the present invention, and the present invention is not limited to this. For example, although the assist guide 38 is opened and closed by rotation and the conveyance path is switched between the carry-in direction and the paper discharge direction to block the path in the carry-in direction to the stacking unit 34, the present invention is not limited to this. The present invention is applicable to any assist guide as long as the assist guide 38 prevents the paper from rebounding to the transport roller R2 at the moment when the paper is discharged from the transport roller R2 to the stacking unit 34 side. Can be applied. Further, the present invention can be applied even if the assist guide has a structure that moves horizontally instead of rotating.

  The intermediate transport unit RU may be an image forming apparatus provided integrally with the image forming unit G, or may be a post-processing apparatus provided integrally with the post-processing unit F. Further, the intermediate transport unit RU may be arranged between a unit that performs the folding process and a unit that performs the stapling process. In this case, the intermediate transport unit RU can stack the folded sheets and collectively transport them to the stapling unit. In other words, in the field of production and printing (PP field, commercial printing, and large-scale printing in a company), it is used together with a post-processing unit, so that a plurality of sheets can be superimposed as appropriate according to the processing speed of the post-processing unit. Can be transported to the post-processing unit. Thereby, a booklet of a desired form can be manufactured while increasing yield and ensuring productivity.

  Further, as a computer-readable medium for a program related to the movement control of the assist guide 38, a non-volatile memory such as a ROM and a flash memory, and a portable recording medium such as a CD-ROM can be applied.

  Further, as a medium for providing program data related to the movement control of the assist guide 38 via a communication line, a carrier wave (carrier wave) is also applied to the present invention, and the controller 33 reads out information from this medium so that the controller 33 reads the information from the medium. Operation control may be performed.

  The embodiment disclosed this time should be considered as illustrative in all points and not restrictive. The scope of the present invention is defined by the terms of the claims, rather than the description above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

DESCRIPTION OF SYMBOLS 10 Image forming system 21 Operation part 24 Paper feed part 27 Display part 28, 31, 41 Communication part 30 Transport part 32, 42 Storage part 33, 44 Control part 34 Accumulation part 35 FD alignment part 36 CD alignment part 37 Switching guide 38 Assist Guide 38b Front end portion 39 Opposite guide 43 Post-processing portion 45 Paper discharge tray 211 Touch panel 222 Scanner 231 Image forming portion 232 Fixing portion 330 Sensor group 333 Paper passage sensor 341 Opposite support portion 343 Support plate portion 351 Stopper 352 Support portions 353, 366, 382 Motor 356 Endless belt 361, 362 Alignment member 381 Projection (projection)
3411, 3431 Support surface 3511 Base 3512 Cushion material 3513 Receiving plate part R1, R2, R3, R4 Transport roller V0 Initial position V1, V2 position

Claims (8)

An intermediate conveyance unit that is disposed between the image forming unit and the post-processing unit, receives paper discharged from the image forming unit, and collects a plurality of sheets and discharges them to the post-processing unit,
A stacking unit that stacks a plurality of sheets in the vertical direction;
A conveying roller that is spaced apart above the stacking unit and discharges paper to the stacking unit so as to fall into the stacking unit;
A closed position that is disposed between the transport roller and the stacking unit, closes a path of a sheet that moves from the transport roller to the stacking unit, and guides the sheet that moves along the path at a position along the path. An assist guide that can move between open positions;
A control unit for controlling the movement of the assist guide;
With
The control unit moves the assist guide from the open position to the closed position after the sheet is discharged by the transport roller and then bounces at the bottom of the stacking unit to return to the transport roller .
The assist guide starts to move from the open position to the closed position before the paper is discharged from the transport roller to the stacking unit.
Intermediate transport unit. The control unit moves the assist guide from the open position to the closed position side so as to come into contact with the rear end when the rear end of the sheet comes out of the transport roller.
The intermediate conveyance unit according to claim 1. A detection unit that detects the paper before the paper is discharged from the transport roller;
The control unit sets a time until the paper ejected from the transport roller bounces back to the transport roller based on the detection timing of the paper by the detection unit, and the assist guide is operated within the set time. Move it to the closed position,
The intermediate conveyance unit according to claim 1 or 2 . The stacking unit has a receiving plate unit that receives the falling paper through a cushioning material.
The intermediate conveyance unit as described in any one of Claim 1 to 3 . The assist guide is a plate-like member having a plurality of projections on the surface facing the paper, a plurality of the projections may be any one of claims 1, which is arranged in the width direction of the sheet 4 The intermediate transport unit described in 1. The control unit controls the movement start timing of the assist guide according to the paper size.
The intermediate conveyance unit according to any one of claims 1 to 5. The control unit controls the movement start timing of the assist guide and the movement speed of the assist guide using a control table according to the basis weight, size, and type of paper.
The intermediate conveyance unit according to any one of claims 1 to 6. An image forming unit for forming and discharging an image on paper;
A post-processing unit that performs post-processing on the image-formed paper;
An intermediate conveyance unit that is disposed between the image forming unit and the post-processing unit, receives the paper discharged from the image forming unit, and collectively discharges the paper to the post-processing unit;
The intermediate transport unit is
A stacking unit that stacks a plurality of sheets in the vertical direction;
A conveying roller that is spaced apart above the stacking unit and that discharges paper to the stacking unit so as to fall into the stacking unit;
A closed position that is disposed between the transport roller and the stacking unit, closes a path of a sheet that moves from the transport roller to the stacking unit, and guides the sheet that moves along the path at a position along the path. An assist guide that can move between open positions;
A control unit for controlling the movement of the assist guide;
With
The control unit moves the assist guide from the open position to the closed position after the sheet is discharged by the transport roller and then bounces at the bottom of the stacking unit to return to the transport roller .
The assist guide starts to move from the open position to the closed position before the paper is discharged from the transport roller to the stacking unit.
Image forming system.

Images