JP5842726B2 - Intermediate transport unit and image forming system - Google Patents

Description

  The present invention relates to an intermediate transport unit and an image forming system including the intermediate transport unit, and more particularly, an intermediate transport that is disposed between an image forming unit and a post-processing unit and can efficiently perform post-processing of image-formed paper. The present invention relates to a unit and an image forming system.

  Conventionally, a post-processing device is connected to an image forming apparatus such as a printer, a copier, or a multifunction peripheral, and punching processing, folding processing, binding (saddle stitching, An image forming system that performs post-processing such as flat binding is known.

  In this system, an intermediate conveyance unit is provided between the image forming apparatus and the post-processing apparatus in order to convey a plurality of sheets from the image forming apparatus to the post-processing apparatus in a batch or to invert and convey the sheets. (For example, refer patent document 1).

  The intermediate transport unit includes a paper stack unit that sequentially stacks the image-formed sheets carried in from the image forming apparatus in the vertical direction, collects a predetermined number of sheets in the sheet stack unit, and collects and discharges them to the post-processing apparatus. .

  Specifically, in the intermediate transport unit, the paper carried from the image forming apparatus is discharged to the paper stack unit side by a transport roller disposed above the paper stack unit, and slides down in the paper stack unit by dropping. Then, a plurality of sheets are stacked in the sheet stack unit by being received by a sheet stopper that moves up and down in the sheet stack unit.

  This intermediate transport unit has alignment means for aligning sheets as preprocessing for processing such as punching processing, binding processing, folding processing, and gluing bookbinding processing. As the aligning means, in addition to the horizontal aligning section that aligns the width direction of the sheet (lateral alignment) with respect to the sheets in the sheet storage section, there is a vertical aligning means that aligns the sheet conveying direction.

  FIG. 1 is a diagram for explaining alignment in a conveyance direction in a conventional intermediate conveyance unit, and is a schematic diagram showing a configuration of a main part of a vertical alignment means.

  The vertical alignment means 31 is a paper stopper 123 that moves up and down in the paper stack section, and a paper stopper 123 that is disposed above the paper stack section and holds the paper S pushed up by the upward movement of the paper stopper 123 and discharges the paper S A driving roller R5 and a driven roller R4.

  In the vertical alignment means 31, the paper accumulated in the paper stack portion is pushed up by the paper stopper 123 and abuts against the nip portions of the carry-out driving roller R 5 and the driven roller R 4 that have stopped rotating. Then, the carry-out driving roller R5 and the driven roller R4 perform alignment by correcting reverse rotation (rotation in the direction of the arrow) while sandwiching the paper pushed up from the stack portion by the paper stopper 123, and correct the paper transport posture. . Thereafter, the sheet is rotated forward with the sheet sandwiched, and the sheet is discharged downstream. As a result, even if the post-processing device is performing post-processing on the previously discharged paper, the subsequent paper can be discharged after performing alignment processing on a plurality of sheets, and post-processing can be performed. It can be done efficiently.

  Further, as an apparatus having a vertical alignment means for performing alignment in the paper conveyance direction, an apparatus disclosed in Patent Document 2 is known. In this 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 when the paper is received, the jogger stopper softens the impact to prevent the paper from bouncing back. A reversing device is disclosed.

JP 2009-274849 A JP-A-6-247603

  In recent years, there has been a demand to form an image using paper with poor cutting and slightly burr and to perform post-processing.

  However, in the image forming system having the conventional intermediate conveyance unit shown in Patent Document 1, it is generally assumed that a sheet that has been finely cut is used. For this reason, when cutting of the carried paper itself is poor and there are some burrs, when the carry-out driving roller R5 and the driven roller R4 sandwiching the paper rotate in the vertical alignment, as shown in FIGS. 2A and 2B, There is a possibility that a part SO at the front end of the paper SW is displaced (flutters) from the predetermined normal position SC. 2A is a perspective view of the sheet shifted from the normal position, and FIG. 2B is a view of the sheet viewed from the axial direction of the carry-out driving roller R5 and the driven roller R4 in FIG. 2A. When the carry-out driving roller R5 and the driven roller R4 rotate in the forward direction, the paper SW is carried out in a skewed state.

  In addition, when performing vertical alignment using Patent Document 2, it is necessary to move the jogger stopper that receives the paper up and down every time the paper is carried in. Therefore, when this intermediate transport unit is used in, for example, an image forming system used in the field of production printing (PP field, commercial printing, and mass printing in a company), productivity is lowered. Therefore, it is not suitable for speeding up the printing process and cannot satisfy the user's request.

  SUMMARY OF THE INVENTION An object of the present invention is to provide an intermediate transport unit capable of ensuring stable alignment while securing productivity even when a sheet with poor cutting is carried in, and an image forming system including the intermediate transport unit.

  The intermediate transport unit according to the present invention is disposed in a stack unit that stores one or a plurality of sheets, and can be driven to rotate forward and backward above the stack unit, and is stored in the stack unit by rotating forward. A pair of transport rollers for transporting one or more sheets to the downstream side in the sheet discharge direction, and one or a plurality of sheets stored in the stack unit are pushed up from below to move the sheet in the sheet discharge direction. Paper conveying means that stops at a position where a gap is formed between the front end portion and the nip portion of the conveying roller pair that rotates in reverse, and aligns the paper in the conveying direction together with the conveying roller pair; The sheet conveying means at the time of alignment is a position where the leading edge of the sheet in the sheet conveyance direction after alignment is at a position where the gap is formed at an interval where it contacts one of the conveying roller pairs at one place or less, and is stopped. The inertial force at the time was a configuration that stops at the position where the sheet pops out the transport roller pair side to form the gap distance so as to contact at two points on the conveying roller pair.

  An image forming system according to the present invention includes an image forming apparatus that forms an image on a sheet, and the intermediate transport that is disposed downstream of the image forming apparatus in a sheet transport direction and receives a sheet on which an image is formed by the image forming apparatus. A configuration is provided that includes a unit and a post-processing device that is disposed downstream of the intermediate transport unit in the paper transport direction and performs post-processing on the paper discharged from the intermediate transport unit.

  According to the present invention, the leading end portion of the aligned paper in the paper carrying direction is in contact with one of the conveying roller pairs at one place or less, and the leading end portion of the paper that is ejected by the inertia force when stopped is the conveying roller. The sheet can be stopped at a position where a gap is formed so as to come into contact with the pair at two places, and alignment can be performed by reverse rotation of the pair of transport rollers. For this reason, even when paper with poor cutting is carried in, stable consistency can be ensured while ensuring productivity.

Schematic diagram showing the main configuration of a conventional vertical alignment means The figure which shows the state where the paper has shifted from the normal position 1 is an overall configuration diagram of an image forming system having an intermediate conveyance unit according to an embodiment of the present invention. Front partial sectional view showing the main configuration of the intermediate transport unit as seen from the direction perpendicular to the transport direction AA sectional view of FIG. FIG. 4 is a schematic configuration diagram of the horizontal alignment unit showing the main configuration of the horizontal alignment unit shown in FIG. The block diagram which shows the principal part structure of the control system of the intermediate conveyance unit which concerns on one embodiment of this invention Front partial sectional view showing the main configuration of the intermediate transport unit Front partial sectional view showing the main configuration of the intermediate transport unit Front partial sectional view showing the main configuration of the intermediate transport unit Front partial sectional view showing the main configuration of the intermediate transport unit Front partial sectional view showing the main configuration of the intermediate transport unit FIG. 14 is a diagram for explaining the vertical alignment operation in the intermediate transport unit according to the embodiment of the present invention. The figure which shows the positional relationship of the stop position of a paper stopper, a paper, and a carry-out drive roller The figure which shows the positional relationship of the stop position of a paper stopper, a paper, and a carry-out drive roller Diagram for explaining conventional vertical alignment FIG. 5 is a control flow diagram when performing vertical alignment in the intermediate transport unit according to the embodiment of the present invention. Schematic diagram showing the vertical alignment operation in the intermediate transport unit according to an embodiment of the present invention. The figure which shows an example of the consistency control table stored in a memory | storage part Front partial sectional view showing the main configuration of the intermediate transport unit

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

[Overview of image forming system]
FIG. 3 is an overall configuration diagram of the image forming system 10 including the intermediate conveyance unit according to the embodiment of the present invention.

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

[Image forming apparatus body G]
The image forming apparatus main body G shown in FIG. 3 includes an image reading unit 1, an image processing unit 2, an image writing unit 3, an image forming unit 4, a paper feeding / conveying unit 5, and a fixing device 6. ing. The image forming unit 4 includes a photosensitive drum 4A, a charging unit 4B, a developing unit 4C, a transfer unit 4D, a separating unit 4E, a cleaning unit 4F, and the like. The sheet conveyance direction in FIG. 3 is a direction that flows from the right side to the left side.

  The paper feeding / conveying means 5 includes a paper feeding cassette 5A, a first paper feeding means 5B, a second paper feeding means 5C, a conveying means 5D, a paper discharging means 5E, and an automatic duplex copying paper feeding means (ADU) 5F.

  On the upper front side of the image forming apparatus main body G, an operation display unit (such as a touch panel) 8 having an input unit and a display unit is disposed. An automatic document feeder DF is mounted on the upper part of the image forming apparatus main body G.

  On the upstream side of the image forming apparatus main body G (on the right side in FIG. 3), a large-capacity paper feeding device LT capable of supplying paper to the image forming apparatus main body G is connected.

  Further, an intermediate transport unit RU is connected to the downstream side of the image forming apparatus main body G (here, the paper discharge unit 5E side on the left side). A post-processing device F is connected to the downstream side in the transport direction of the intermediate transport unit RU (the left side of the intermediate transport unit RU in FIG. 3).

  The document placed on the document table of the automatic document feeder DF is read on one or both sides of the document by the optical system of the image reading unit 1. The analog signal photoelectrically converted after reading is sent to the image writing unit 3 after processing such as analog processing, A / D conversion, shading correction, and image compression processing in the image processing unit 2. In the image writing unit 3, output light from the semiconductor laser is irradiated onto the photosensitive drum 4 </ b> A of the image forming unit 4 to form a latent image. In the image forming unit 4, processes such as charging, exposure, development, transfer, separation, and cleaning are performed.

  The sheet S fed by the first sheet feeding unit 5B is transferred to the sheet S by the transfer unit 4D. The paper S carrying the image is fixed by the fixing device 6 and sent from the paper discharge means 5E to the intermediate transport unit RU. Alternatively, the single-sided image processed paper S sent to the automatic double-sided copy paper feeding unit 5F is again subjected to double-sided image processing in the image forming unit 4 and then discharged by the paper discharge unit 5E and sent to the intermediate transport unit RU.

  The communication means of the main control unit 9A arranged in the image forming apparatus main body G and the communication means of the control unit 9B arranged in the intermediate transport unit RU are connected by a communication line 9C, and input signals and control signals are transmitted. Give and receive.

  The control unit 9B controls the operation of each unit in the intermediate transport unit RU through transmission / reception of signals with the main control unit 9A. Details of the control unit 9B will be described later.

  The large-capacity paper feeding device LT includes a paper stacking unit 7A, a first paper feeding unit 7B, and the like, and continuously feeds a large amount of paper S to the image forming apparatus main body G.

  The post-processing device F receives the paper S discharged from the intermediate transport unit RU and performs post-processing. Examples of the post-processing include at least one of a punching process, a binding process, a folding process, a glue binding process, and the like. Further, the post-processing unit F is provided with a transport path that can discharge paper without going through post-processing, and the paper transported from the intermediate transport unit RU is passed through the transport path to discharge paper without performing post-processing. You can also.

[Configuration of intermediate transport unit RU]
The intermediate transport unit RU forms an image so that the efficiency of the entire system does not decrease when there is a difference between the processing capability of the image forming apparatus main body G and the processing capability of the post-processing apparatus F. It is a transfer device that delivers the apparatus main body G to the post-processing apparatus F.

  The intermediate transport unit RU is provided between the image forming apparatus main body G and the post-processing apparatus F. The intermediate transport unit RU receives sheets printed by the image forming apparatus main body G one by one and transports them to the post-processing apparatus F as they are, or stacks the printed sheets in the stack unit 12 and collects the stacked sheets. Or collectively transported to the post-processing apparatus F in units of a plurality of sheets.

  4 to 6 show the intermediate transport unit RU according to the embodiment of the present invention. 4 is a front partial cross-sectional view showing the configuration of the main part of the intermediate transport unit RU viewed from a direction perpendicular to the transport direction, FIG. 5 is a cross-sectional view taken along line AA in FIG. 4, and FIG. It is a figure which shows the principal part structure of 122, and is the schematic block diagram which looked at the horizontal alignment part 122 from upper direction.

  As shown in FIG. 4, the intermediate transport unit RU includes a paper carry-in unit 11, a paper stack unit (hereinafter referred to as “stack unit”) 12, a paper discharge unit 13, and a swing guide plate G5.

  The paper carry-in unit 11 receives the paper S discharged from the image forming apparatus main body G and carries it into the stack unit 12. Specifically, the paper carry-in unit 11 includes a pair of conveyance rollers R1, R2, a carry-in driving roller R3, a pair of guide members 120, a switching gate 129, and guide members G1, G2. The pair of guide members 120 are fixed guide members that guide the paper S horizontally, and the guide members G1 and G2 are fixed guide members that guide the paper from the horizontal direction to the vertical direction below.

  The paper carry-in unit 11 conveys the paper S received from the image forming apparatus main body G to the stack unit 12 side by the conveyance roller pair R1, R2, the carry-in driving roller R3, the pair of guide members 120, and the guide members G1, G2. (Discharge.

  The transport roller pair R1, R2 is rotated by driving a motor M1 (see FIGS. 4 and 7), and the carry-in drive roller R3 is connected to the transport roller pair R2 by a belt or the like and rotates.

  A switching gate 129 is disposed in the middle of the pair of guide members 120. The switching gate 129 is driven by the solenoid SOL2 (see FIGS. 4 and 7) and rotates to switch between the horizontal conveyance of the paper S and the conveyance of the stack S12.

  The carry-in driving roller R3 and the driven roller R4 (specifically, the driven rollers R4b and R4c shown in FIG. 5) are provided in the vicinity of the downstream end of the conveyance path formed by the guide members G1 and G2, and the swing guide plate G5 is carried in. It is provided further downstream of the driving roller R3. Here, the terms “downstream” and “upstream” are used based on the transport direction of the paper S.

  The paper S discharged from the carry-in drive roller R3 and the driven roller R4 and dropped is guided by the swing guide plate G5 and stored in the stack unit 12. The sheets are stacked by storing a plurality of sheets in the stack unit 12.

  The swing guide plate G5 is a member having two paper guide portions G5a and G5b, and is disposed in the vicinity of the junction point of the paper transport path between the paper carry-in portion 11 and the stack portion 12. Further, the swing guide plate G5 is driven by a solenoid SOL1 (see FIGS. 4 and 7) as a guide plate drive unit, and swings and rotates about the axis X.

  The stack unit 12 can receive and store a plurality of sheets S from the sheet carry-in unit 11, and moves the stored plurality of sheets S to the sheet discharge unit 13 while reversing the transport direction (front and back).

  Specifically, the stack unit 12 includes a pair of parallel paper holding plates 121 as stationary guide plates extending in the vertical direction for guiding the paper S, a lateral alignment unit 122 for aligning the paper S in the width direction, And a paper stopper 123 that accommodates and moves the paper S.

  The paper S carried in from the paper carry-in unit 11 is held at the front end in the paper carry-in direction by the paper stopper 123 and held upright in the vertical direction by the paper holding plate 121.

  The lateral alignment unit 122 is a unit that aligns the sheet S in the width direction. As is well known, the motor M4 (FIG. 6, FIG. 6) sandwiches the sheet S positioned between the sheet holding plates 121 of the stack unit 12 in the width direction. The sheet S is aligned by reciprocating with the driving of FIG. In the horizontal alignment, the sheet S is aligned in the width direction of the sheet and is positioned at a normal position in the width direction. This regular position is a position where the aligned sheet S is conveyed without skew when conveyed by the sheet stopper 123, the carry-out driving roller (registration roller) R5, and the driven roller R4.

  As shown in FIG. 6, the lateral alignment portion 122 includes a pair of left and right CD (Cross Direction) alignment plates 122A, a motor M4, a belt 127, pins 128A and 128B, and the like. The pair of left and right CD alignment plates 122A engages with pins 128A and 128B locked to a belt 127 rotated by a motor M4, moves in the paper width direction, and aligns the paper S in the width direction.

  As described above, the sheet S arranged on the sheet holding plate 121 of the stack unit 12 is movable in the vertical direction by the sheet stopper 123 of the sheet conveying unit.

  The paper stopper 123, together with the motor M3, the belt 125, and the guide rod 126, constitutes a paper transport unit. The sheet stopper 123 is movable up and down by the motor M3, the belt 125, and the guide rod 126. The sheet S is pushed up from below by the movement of the sheet stopper 123 in the vertical direction, and moves between the sheet holding plates 121 in the vertical direction.

  Specifically, the paper stopper 123 is connected to the belt 125 and is provided in a state of being guided by a vertical guide rod 126. The paper stopper 123 moves in the vertical direction as the belt 125 driven by the motor M3 (see FIGS. 4 and 7) rotates. The motor M3 is a stepping motor, and the paper stopper 123 can move at a set speed and stop at a predetermined position at a speed set by the motor M3.

  Further, as will be described later, the paper stopper 123 moves from the initial stop position P0 to the first stop position P1 or the second stop position (alignment position) P2 in the paper transport process, and each stop position varies depending on the paper size. It is set to be changeable.

  The paper stopper 123 receives the paper S stored in the stack portion 12 (specifically, between the paper holding plates 121) and pushes it upward from below. The paper stopper 123, together with the discharge driving roller R5 and the driven roller R4 (specifically, the driven rollers R4a and R4d shown in FIG. 5) of the paper discharge unit 13, aligns the paper in the conveyance direction, that is, longitudinal alignment (Feed Direction). Alignment). In the vertical alignment, the paper S is aligned in the transport direction and is positioned at a normal position in the transport direction. This regular position is a position where the aligned sheet S is conveyed without skew when conveyed by the sheet stopper 123, the carry-out driving roller R5, and the driven roller R4.

  The paper discharge unit 13 is a part for carrying out the paper S stored in the stack unit 12. The paper discharge unit 13 includes a pair of guide members 120 that are horizontal guide members, guide members G3 and G4 as branch guide units that guide the paper S from the vertical direction to the horizontal direction, and a vertical alignment unit. As a carry-out driving roller R5 and a pair of conveying rollers R6 and R7.

  The driven roller R4 contacts the carry-out driving roller R5 and rotates. The carry-out drive roller R5 is connected to a motor M2 as a carry-out roller drive unit and is driven to rotate. The carry-out driving roller R5 and the driven roller R4 as a paper carry-out roller pair having a vertical alignment function carry out the paper S while being switched back from the stack unit 12 with the paper S interposed therebetween. The carry-out drive roller R5 has a higher friction coefficient μ than the driven roller R4. In addition, one of the carry-out drive roller pair R1 and R2 and the carry-in drive roller R3 are each more than a pair of rollers that form a nip portion. The friction coefficient μ is large.

  As shown in FIG. 5, the driven roller R4 is composed of four driven rollers R4a, R4b, R4c, and R4d here.

  In these driven rollers R4, the driven rollers R4b and R4c at the center in the width direction (the direction perpendicular to the paper conveyance direction, hereinafter the same) are in contact with the carry-in driving roller R3. Further, the driven rollers R4a and R4d at both ends of the driven rollers R4b and R4c come in contact with the carry-out driving roller R5 and are driven to rotate. The driven rollers R4b and R4c at the center and the driven rollers R4a and R4d at both ends can be rotated independently.

  FIG. 7 is a block diagram illustrating a main configuration of a control system of the intermediate transport unit RU.

  The intermediate transport unit RU includes a control unit 9B connected to the main control unit 9A, and a storage unit 91, motors M1 to M4, a sensor SE, solenoids SOL1 and SOL2 are connected to the control unit 9B.

  The control unit 9B includes a CPU (Central Processing Unit), a ROM (Read Only Memory), a RAM (Random Access Memory), and the like (not shown). The CPU reads out a program corresponding to the processing content from the ROM, develops it in the RAM, and centrally controls the operation of each block of the intermediate transport unit RU in cooperation with the developed program. At this time, various data stored in the storage unit 91 are referred to. The storage unit 91 is configured by, for example, a nonvolatile semiconductor memory (so-called flash memory) or a hard disk drive. The storage unit 91 stores a control table used for the swing guide plate G5, the switching gate 129, the sheet stopper 123, the conveyance control of the sheet carry-in unit 11, the drive control of the lateral alignment unit 122, and the like.

  Specifically, the control unit 9B, based on information from the main control unit 9A provided in the image forming apparatus main body G and the paper detection signal of the sensor SE provided in the paper carry-in unit 11, the motors M1 to M4, The solenoids SOL1 and SOL2 are driven.

  The start timings of the motors M1 to M4 and the solenoids SOL1 and SOL2 are determined based on the paper detection signal of the sensor SE.

  That is, the control unit 9B analyzes the job information transmitted from the image forming apparatus main body G via the main control unit 9A, and reads the sheet conveyance conditions. Then, the control unit 9B drives and controls the motors M1 to M4 and the solenoids SOL1 and 2 in accordance with the read conveyance conditions, and conveys the paper carried from the image forming apparatus main body G.

  The control unit 9B drives and controls the motor M1, and rotationally drives the rollers R1 to R3 (conveying roller pairs R1, R2 and the carry-in driving roller R3) to convey the paper. The transport rollers R1 to R3 are continuously rotated by driving the motor M1 during transport. Further, the conveyance roller pair R6 and R7 may be similarly rotationally driven by using the motor M1.

  Further, the control unit 9B drives and controls the motor M2 to rotate forward, thereby rotating the carry-out driving roller R5 in the forward direction and transporting the sheet in the transport direction. The control unit 9B moves the paper stopper 123 in the vertical direction of the stack unit 12 by driving and controlling the motor M3 to rotate forward and backward. Here, the paper stopper 123 is raised by the forward rotation of the motor M3, and the paper stopper 123 is lowered by the reverse rotation of the motor M3.

  In particular, the control unit 9B rotates the carry-out driving roller R5 via the motor M2 and raises the paper stopper 123 via the motor M3 and stops it at the alignment position, thereby aligning the paper in the conveyance direction (vertical). Alignment).

  Further, the control unit 9B drives and controls the solenoids SOL1 and SOL2 to drive the swing guide plate G5 and the switching gate 129, thereby changing the position in the paper transport path.

  In particular, when performing alignment in the paper conveyance direction, that is, vertical alignment, the control unit 9B reversely rotates the carry-out driving roller R5 using the alignment control table (see FIG. 15) stored in the storage unit 91. While driving, the paper stopper 123 is moved upward.

  Thus, each part is drive-controlled by the control part 9B, and the paper carried in from the image forming apparatus main body G is straightly conveyed as it is, is conveyed to the post-processing apparatus F, or the stack part 12 (refer FIG. 3). Or a plurality of sheets are collected and then transferred to the post-processing apparatus F.

[Operation of intermediate transport unit RU]
Next, the operation of the intermediate transport unit RU will be described with reference to FIGS.

  8 to 12 are front sectional views of the intermediate transport unit RU.

  FIG. 8 shows a sheet carry-in stage to the intermediate transport unit RU. As shown in FIG. 8, the first sheet (preceding sheet) S1 discharged from the image forming apparatus main body G is horizontally conveyed through the sheet carry-in section 11 by the conveyance roller pair R1, R2, and the sheet S1 is a sensor. Detected by SE.

  In FIG. 8, the conveyance roller pair R1, R2 and the carry-in drive roller R3 are driven and rotated by the motor M1, and the carry-in drive roller R3 sandwiches and conveys the sheet S1 by contact with the driven roller R4. In the process in which the first sheet S1 is conveyed from the sheet carry-in section 11 to the stack section 12, the sheet S1 is guided by the guide members G1, G2, the swing guide plate G5, and the sheet holding plate 121. The swing guide plate G5 is rotated counterclockwise, receives the paper S carried in from the carry-in driving roller R3 by the paper guide portion G5a, and guides it to the stack portion 12.

  As a result of the paper carry-in shown in FIG. 8, as shown in FIG. 9, the first paper S <b> 1 stops when the front end in the paper carry-in direction abuts against the FD alignment plate 123 </ b> A that is the abutting stop surface of the paper stopper 123. At this time, the sheet stopper 123 is positioned at the initial stop position P0 via the motor M3 (see FIG. 7).

  Next, the motor M3 is driven to rotate in the forward direction, and the paper stopper 123 is moved upward via the belt 125 and stops at the first stop position P1 shown in FIG. When the paper stopper 123 is raised, the swing guide plate G5 is swung in the clockwise direction by the drive of the solenoid SOL1 and positioned at the position shown in FIG. In the stack unit 12, since the paper S1 is reversed, the front end in the paper carry-out direction is the same as the rear end in the paper carry-in direction.

  When the swing guide plate G5 is thus rotated clockwise and the lower end of the swing guide plate G5 is close to the wall surface of the guide member G4, the sheet S1 is guided by the swing guide plate G5, and the wall surface of the guide member G4 It will be conveyed along. By this swinging of the swinging guide plate G5, the leading end of the sheet S1 in the carry-out direction is guided along the wall surface of the guide member G4. Thereby, the conveyance defect which will remove | deviate from the guide member G3 by abutting the lower end part of the guide member G3 etc. is prevented.

  When the paper stopper 123 reaches the first stop position P1, the leading end of the paper S1 in the carry-out direction is located above the lower end of the guide member G2. Thus, even if the subsequent second sheet S2 is carried in from the guide members G1 and G2, the leading ends of the first sheet S1 and the second sheet S2 do not interfere with each other, and the second sheet Does not enter the carry-out side of the first sheet S1.

  Next, as shown in FIG. 11, the second sheet (following sheet) S2 is sandwiched between the roller pair R2, the carry-in driving roller R3, and the driven roller R4, and is guided and guided by the guide members G1 and G2. . The leading edge of the second sheet S2 does not interfere with the leading edge of the first sheet S1, proceeds on the transport roller R3 side of the first sheet S1, and is transported toward the FD alignment plate 123A of the sheet stopper 123. Then, the sheets S1 and S2 are stored in the sheet stopper 123 in a state where they overlap each other.

  Next, the paper stopper 123 descends due to the reverse rotation of the motor M3, and moves to the initial stop position P0 that receives the loaded paper S2. As shown in FIG. Sheets S1 and S2 are held.

  Next, the motor M3 is driven to raise the paper stopper 123.

  Then, the transport roller R5 rotates in the reverse direction, and the paper stopper 123 stops at a predetermined position, thereby performing vertical alignment of the paper. Further, the lateral alignment of the paper is also performed, and then the paper is discharged in the intermediate transport unit RU.

  In the vertical alignment of the paper, the controller 9B raises the paper stopper 123 and pushes up the paper while rotating the carry-out driving roller R5 in the reverse direction. Then, the sheet is positioned at a position where a predetermined gap H (see FIG. 13) is opened from the center position of the carry-out drive roller R5 rotating in reverse, that is, the nip position between the carry-out drive roller R5 and the driven roller R4, and stopped. At this position, the sheet SS (here, the sheet bundle of the sheets S1 and S2) is abutted against the FD alignment plate 123A of the sheet stopper 123 by the carry-out driving roller R5 that rotates in reverse. Thereby, when the paper is skewed, the paper is held by the paper stopper 123 with the skew corrected.

  That is, the controller 9B raises the paper stopper 123 via the motor M3 and stops it at the alignment position while rotating the carry-out driving roller R5 via the motor M2.

  This alignment position is a gap having an interval such that the leading end of the aligned sheet in the sheet unloading direction contacts one of the unloading driving roller R5 and the driven roller at one point (one point) or less, that is, contacts at one point or does not contact both. This is a stop position where H (see FIG. 13) is formed. In addition, this alignment position has two paper discharge direction leading ends of the paper jumping out to the carry-out driving roller R5 and the driven roller R4 (conveying roller) side by inertia force at the time of stopping at two places on the carry-out driving roller R5 and the driven roller R4. This is a position where a gap H (see FIG. 13) with an interval that makes contact at (two points) is formed.

  As a result, the paper S moves to the paper stopper 123 side by the reverse rotation of the carry-out driving roller R5, is abutted against the paper stopper 123, and alignment (vertical alignment) of the paper conveyance direction is performed.

  FIG. 13 is a schematic diagram for explaining the vertical alignment operation in the intermediate transport unit RU.

  As shown in FIG. 13, the second stop position (alignment position) P2 of the sheet stopper 123 (specifically, the FD alignment plate 123A of the sheet stopper 123) is the center position N of the carry-out driving roller R5, the leading end of the sheet SS, and the like. This is the position at which the gap H is formed.

  That is, during the vertical alignment, the length of the FD alignment plate 123A of the paper stopper 123 and the carry-out drive roller R5 is set to be longer than the paper length of the moving paper SS, and the carry-out drive roller R5 rotates in the reverse direction. A gap H is formed when abutting against the FD alignment plate 123A.

  The second stop position [alignment position] P2 of the paper stopper 123 (specifically, the FD alignment plate 123A) that forms the gap H at the time of vertical alignment is the positional relationship between the paper SS and the carry-out driving roller R5 as shown in FIG. The positional relationship shown in FIG. 15 is set.

  First, as shown in FIG. 14, the stop position (alignment position P2) of the paper stopper 123 is such that the front end of the paper SS supported by the paper stopper 123 and the carry-out driving roller R5 and the driven roller R4 are separated by a gap H during alignment. Is a position (condition 1) that contacts at one place in the front end of the paper discharge direction. Alternatively, as shown in FIG. 15, at the time of alignment, the leading end of the paper SS supported by the paper stopper 123 is not in contact with the carry-out driving roller R5 and the driven roller R4 (condition 2). These stop positions (alignment positions) are two places at the leading end of the paper in the paper discharge direction (the front edge of the paper) when the paper stopper 123 stops and the paper jumps out due to the inertial force. This is a position (condition 3) for forming an interval (gap H) in contact with the driven roller R4.

  This is different from the configuration of the conventional vertical alignment unit that performs vertical alignment by moving the sheet with the sheet stopper 123 (123A) and abutting against the pair of carry-out driving rollers R5 and R4 as shown in FIG. That is, in the present embodiment, the paper on the paper stopper 123 (123A) does not contact (contact at two points) with both the carry-out driving roller R5 and the driven roller R4 that rotate in reverse (see FIG. 16). This makes it difficult for paper misalignment to occur.

  Further, when the paper that has jumped out of the paper stopper 123 due to inertia force contacts the carry-out driving roller R5 and the driven roller R4 at two positions on the leading edge, skew correction can be performed by reverse rotation of the carry-out drive roller R5. .

  By forming the gap H, even when the carry-out driving roller R5 rotates in the reverse direction, the sheet is not pressed downward compared to the case where there is no gap H, and the sheet is in contact with the FD alignment plate 123A. There is no stress. As a result, skew due to paper misalignment can be prevented. The center position N corresponds to a nip position by the carry-out driving roller R5 and the driven roller R4.

  Further, the alignment position (second stop position) P2 is changed by the control unit 9B in accordance with the thickness of the paper, and an appropriate gap H is formed during alignment. The gap H is a gap formed by a position that satisfies either of the conditions 1 and 3 or the conditions 2 and 3. The alignment position P2 is a position that satisfies any of the above conditions 1 and 3 or 2 and 3 corresponding to the type, size, orientation, and eye of the paper. Note that the basis weight, rigidity, and assumed frictional force differ depending on the type of paper.

  FIG. 17 is a control flow diagram when performing vertical alignment in the intermediate conveyance unit according to the embodiment of the present invention, and FIG. 18 illustrates the vertical alignment operation in the intermediate conveyance unit according to the embodiment of the present invention. It is a schematic diagram shown. In FIG. 18, a sheet bundle of two sheets S1 and S2 will be described using “sheet SS” for convenience.

  As shown in FIG. 17, in step S <b> 11, the control unit 9 </ b> B sets the moving amount of the paper stopper 123 and the moving speed of the paper stopper 123. Here, the control unit 9B uses the control table of the storage unit 91 to set the moving amount of the paper stopper 123 (specifically, the FD alignment plate 123A of the paper stopper 123) and the moving speed of the paper stopper 123.

  FIG. 19 shows an example of the alignment control table 95 stored in the storage unit 91. The “moving speed Vmm / s” and “moving amount Wmm” of the sheet stopper 123 are set as the setting conditions corresponding to each sheet SS. Is set. Note that the sheets differ depending on the “type”, “size”, “orientation”, “eyes (fiber arrangement)”, and the like. For example, as an example of the “size” and “orientation” of the paper, the A3 vertical FD length is 420 mm, the size A4 vertical FD length is 297 mm, and the size A4 horizontal FD length is 210 mm. Note that the “eyes” of the paper shown in FIG. 19 are indicated by “T eyes” for the vertical and “Y eyes” for the horizontal. The moving speed V and the moving amount W corresponding to each sheet are the moving speed and moving amount of the sheet stopper 123 from the initial position P0 to the stop position at the time of alignment. Corresponding to these settings, the length of “between the sheet and the center of the roller (the length between the leading edge of the sheet and the center of the carry-out driving roller R5) mm”, that is, the stop position of the sheet stopper 123 at the time of alignment is Is set. In the alignment control table 95, the “movement speed Vmm / s” of the sheet stopper 123 and the movement acceleration amm / s may be associated with each other for each sheet type. When performing vertical alignment, the controller 9B drives the motor M3 to move the paper stopper 123 based on the setting conditions corresponding to the paper.

  The “movement speed V” and “movement amount W” of the paper stopper 123 corresponding to the paper, and “between the paper and the roller center” are the center position of the carry-out driving roller R5 from the initial position P0 of the paper stopper 123 (that is, the nip). It is set using a length (for example, 530 mm).

  In this way, using the matching control table 95 shown in FIG. 19, the control unit 9B sets the type, size, orientation, movement speed V corresponding to the eye, and movement amount W corresponding to the eyes, and proceeds to step S12. .

  In step S12, the controller 9B drives the motor M3 to raise the sheet stopper 123 (specifically, the FD alignment plate 123A) at the set moving speed V and moving amount W (see FIG. 18A). That is, as shown in FIG. 18A, the sheet SS is raised in the direction of the arrow at the moving speed V and the moving amount W.

  In step S13, the controller 9B drives the motor M2 (reverse rotation drive) to reversely rotate the carry-out drive roller R5 (see FIG. 18B), and proceeds to step S14. That is, before the paper alignment, the carry-out drive roller R5 rotates in the reverse direction.

  In step S14, the control unit 9B drives the motor M3 to stop the paper stopper 123 (specifically, the FD alignment plate 123A) at the alignment position (so-called second stop position P2) where the set movement amount W is achieved. (See FIG. 18C).

  That is, the paper stopper 123 pushes up the paper SS to the front of the carry-out driving roller R5 and stops. At this time, when the moving paper stopper 123 stops, the paper SS pushed up by the paper stopper 123 by the inertial force jumps out in the moving direction, and at the leading end portion in the paper carrying-out direction, to the carry-out driving roller R5 and the driven roller R4. Contact at two locations. In FIG. 18C, as indicated by a portion J, the sheet SS (specifically, the front end in the sheet conveyance direction) that has jumped upward from the sheet stopper 123 due to the inertia force is transferred to the unloading driving roller R5 and the driven roller R4. Contact is made at two points (two points) separated in the direction.

  In step S15, the sheet SS is abutted against the sheet stopper 123 and aligned by the carry-out driving roller R5 rotating in the reverse direction (see FIG. 18D). That is, as shown in FIG. 18D, the sheet SS is returned to the FD alignment plate 123A side by the reverse rotation D2 of the carry-out driving roller R5, and alignment is performed at the rear end of the sheet contacting the sheet stopper 123. At this time, as indicated by a portion K in FIG. 18D, the leading end side of the sheet is in contact with or separated from the carry-out drive roller R5 (or the carry-out drive roller R5 and the driven roller R4). Thereby, the deviation (flapping) of the paper SS does not occur. As described above, the trailing edge of the sheet is also aligned, and the inclination (skew) of the sheet SS is corrected. At this time, the third sheet S3 (see FIG. 20) is carried in by the roller pair R1 and the width alignment of the sheets SS (S1, S2) by the lateral alignment unit 122 through the driving of the motor M4. Done.

  In step S16, the control unit 9B stops the reverse rotation of the carry-out driving roller R5 via the motor M2, and ends the vertical alignment of the paper SS (see FIG. 18E).

  In step S17, the control unit 9B drives the motor M3 to raise the paper stopper 123, thereby driving up the paper SS and driving the motor M2 (forward rotation driving) to rotate the carry-out driving roller R5 forward. (In the direction of arrow D1). As a result, the carry-out driving roller R5, together with the driven roller R4, sandwiches the paper SS at the nip position by the nip portion and conveys it downstream in the conveying direction (arrow D4 direction) (see FIG. 18F).

  Thus, when the carry-out drive roller R5 is rotated forward to convey the paper downstream, the carry-out drive roller R5 and the driven roller R4 together with the driven roller R4 drive the paper SS of the paper S1, S2 by the drive control of the control unit 9B. Is conveyed toward the guide member 120 of the paper discharge unit 13.

  After the carry-in drive roller R3 and the driven roller R4 are rotated, as shown in FIG. 20, the control unit 9B operates the motor M3 to lower the paper stopper 123 and move the paper stopper 123 to the initial stop position P0. Let As the sheet stopper 123 is lowered, the conveyance roller pair R2 is rotated, and the third sheet S3 is conveyed toward the sheet stopper 123 that moves to the initial stop position P0 via the guide members G1 and G2.

  The states shown in FIGS. 8 to 12 and 20 are repeated, and continuous conveyance is performed in which the sheets S are carried into the intermediate conveyance unit RU one by one and discharged two by two.

  According to the present embodiment, the intermediate transport unit RU includes the stack unit 12 that stores one or a plurality of sheets. A carry-out driving roller R5 and a driven roller R4 are disposed above the stack portion 12 so as to be able to drive forward and reverse. The carry-out drive roller R5 and the driven roller R4 rotate forward to convey one or more sheets stored in the stack unit 12 to the downstream side in the sheet carry-out direction. The paper stopper 123 pushes up one or more sheets stored in the stack unit 12 from below to above. The sheet stopper 123 stops at an alignment position P2 where a gap H (see FIG. 13) is formed between the leading end portion of the sheet in the sheet unloading direction and the nip portion of the unloading driving roller R5 and the driven roller R4 that rotate in reverse. At this stop position, the paper stopper 123 aligns the paper in the transport direction together with the carry-out driving roller R5 and the driven roller R4. The sheet stopper 123 forms an alignment gap H (see FIG. 13) at an interval such that the leading end of the aligned sheet in the sheet unloading direction comes into contact with one of the unloading driving roller R5 and the driven roller R4 at one place or less. Stop at P2. This alignment position P2 has a gap H (see FIG. 13) at which the paper that jumps out to the carry-out driving roller R5 and the driven roller R4 due to the inertial force at the time of contact comes into contact with the carry-out drive roller R5 and the driven roller R4 at two locations. ). The sheet is stopped at this position and aligned in the sheet conveyance direction, that is, vertically aligned with the carry-out driving roller R5 and the driven roller R4 rotating in reverse.

  Therefore, when the sheets are aligned at the normal position during the vertical alignment, the sheet on the sheet stopper 123 is separated from the nip portion by the gap H. Specifically, the sheet is in contact with one of the carry-out driving roller R5 and the driven roller R4 at one position in the paper carry-out direction or the carry-out drive roller R5 and the driven roller R4 through the gap H. Not in a state. Further, the gap H is a gap having an interval such that when the paper is ejected by an inertial force at the time of stopping, the paper is brought into contact with the carry-out driving roller R5 and the driven roller R4 at two positions at the front end portion of the paper in the paper carry-out direction. For this reason, even if it aligns by reverse rotation of carrying-out drive roller R5 and driven roller R4, a paper does not shift from a regular position.

  As a result, even when paper with poor cutting and slightly burr is carried in, stable consistency can be ensured while ensuring productivity. The paper stopper 123 stops at the alignment position P2 corresponding to at least one of the paper type, size, orientation, and paper eye direction of the paper. Further, the moving speed of the paper stopper 123 may be set corresponding to at least one of the paper type, size, orientation, and paper eye direction of the paper. Furthermore, the moving speed and acceleration of the paper stopper 123 may be set corresponding to at least one of the paper type, size, orientation, and paper eye direction of the paper. Thus, even when the stop position is changed according to the sheet and a sheet with poor cutting is carried in, stable consistency can be ensured while ensuring productivity. That is, depending on the type of paper (basis weight, strain, frictional force), the amount of paper ejected to the carry-out driving roller R5 and driven roller R4 side differs with respect to the pushing-up force of the paper stopper 123. However, by setting the moving speed, moving amount, and the like of the paper stopper 123 corresponding to each paper, it is possible to ensure stable consistency while ensuring productivity.

  In the present embodiment, the case of alignment in the transport direction with respect to the two sheets S1 and S2, that is, the case of vertical alignment has been described. For example, a sheet of paper is pushed up by the paper stopper 123, and the paper is positioned at a position where an appropriate gap H (see FIGS. 14 and 15) is left from the reversely rotating carry-out driving roller R5, thereby performing vertical alignment of the paper. You may go.

  In the present embodiment, the number of sheets S stored in the stack unit 12 is two, but it is of course possible to discharge one or more sheets after storing them in the stack unit 12.

  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 11 Paper carry-in part 12 Stack part 13 Paper discharge part 91 Memory | storage part 95 Alignment control table 9A Main control part 9B Control part 121 Paper holding plate 122 Lateral alignment part 122A CD alignment board 123 Paper stopper (paper conveyance means)
123A FD alignment plate 125, 127 belt 126 guide rod 129 switching gate 128A pin F post-processing device G image forming apparatus main body M1, M2, M3, M4 motor P0 initial stop position P1 first stop position P2 alignment position R3 carry-in driving roller R4 Followed roller R5 Unloading drive roller (conveyance roller)
RU Intermediate transport unit S, S1, S2, SS Paper SE sensor SOL1, SOL2 Solenoid

Claims (5)

A stack unit for storing one or more sheets;
A pair of transport rollers that are disposed so as to be capable of forward and reverse rotation freely above the stack part and forwardly rotate, thereby transporting one or a plurality of sheets stored in the stack part to the downstream side in the sheet carry-out direction,
One or a plurality of sheets stored in the stack unit are pushed upward from below, and a gap is formed between the leading end of the sheet in the sheet carrying direction and the nip portion of the transport roller pair that rotates in reverse. Paper conveying means that stops at a position where the paper is aligned with the pair of conveying rollers in the conveying direction;
Have
The sheet conveying means at the time of alignment is a position where the leading end portion of the sheet after alignment is in a position where the gap is formed so as to contact one of the conveying roller pairs at one place or less, and stopped. The paper that jumps out to the side of the conveying roller due to the inertia force at the time stops at a position that forms the gap with an interval such that the paper contacts the pair of the conveying roller at two locations,
Intermediate transport unit. The paper conveying means stops at a position corresponding to at least one of the paper type, size, orientation, and paper eye direction of the paper;
The intermediate conveyance unit according to claim 1. The moving speed of the paper conveying means is set corresponding to at least one of the paper type, size, orientation, and paper eye direction of the paper.
The intermediate conveyance unit according to claim 1. The moving speed and acceleration of the paper conveying means are set corresponding to at least one of the paper type, size, orientation, and paper eye direction of the paper.
The intermediate conveyance unit according to claim 1. An image forming apparatus for forming an image on paper;
The intermediate conveyance unit according to any one of claims 1 to 4, wherein the intermediate conveyance unit is disposed downstream of the image forming apparatus in a sheet conveyance direction and receives a sheet on which an image is formed by the image forming apparatus.
A post-processing device that is disposed downstream of the intermediate transport unit in the paper transport direction and performs post-processing on the paper discharged from the intermediate transport unit.
Image forming system.

Images