JP6089690B2 - Paper processing apparatus and image forming system - Google Patents

Description

  The present invention relates to a sheet processing apparatus, an image forming system, and a sheet conveying method, and in particular, a sheet-like recording medium such as a loaded sheet, a transfer sheet, a printing sheet, and an OHP sheet (in the present specification and claims, The present invention relates to a sheet processing apparatus that performs a folding process on a sheet, and an image forming system including the sheet processing apparatus and an image forming apparatus such as a copying machine, a printer, a facsimile, or a digital multifunction peripheral.

  An image forming system including an image forming apparatus and a sheet processing apparatus is widely used because it can perform image forming and sheet post-processing as a series of operations. Examples of post-processing include alignment processing, sorting processing, folding processing, binding processing, and bookbinding processing. These post-processing functions are provided as a single or a plurality of paper post-processing devices according to applications, and are used by being connected to the subsequent stage of the image forming apparatus. When these post-processing are performed, processing time occurs, and it is necessary to wait for the start of sheet conveyance on the image forming apparatus side for that processing time.

  Therefore, in order to prevent such a decrease in productivity, sheets conveyed from the image forming apparatus are temporarily stored in the post-processing apparatus, and image formation on the image forming apparatus side is performed for the time required for the post-processing. A pre-stack mechanism that allows processing without waiting is known. This pre-prestack mechanism is a mechanism that waits for the sheet conveyed from the image forming apparatus side in the conveyance path of the post-processing apparatus until the post-processing is completed. A technique relating to this prestack is disclosed in, for example, Japanese Patent Laid-Open No. 4-226263 (Patent Document 1).

  On the other hand, in addition to the pre-stack, a technique in which a recirculation path is provided in order to realize a plurality of diffractions with a simple configuration is also disclosed in, for example, Japanese Patent Application Laid-Open No. 2004-10271 (Patent Document 2).

  However, the pre-stack mechanism described in Patent Document 1 does not necessarily prevent a decrease in productivity. If the post-processing time becomes long, the conveyance of paper is started on the image forming apparatus side after all. You need to wait that much.

  In order to avoid this, a prestack mechanism may be further provided in the apparatus upstream of the post-processing apparatus. However, if a pre-stack mechanism is provided in addition to the original mechanism provided in the upstream machine, a dedicated path for the pre-stack is required, resulting in an increase in the size of the apparatus.

  In order to avoid this, even if the recirculation path described in Patent Document 2 is taken in, it is necessary to provide a mechanism dedicated to folding when performing the folding process, which increases the size of the apparatus. Further, in the technique described in Patent Document 2, no particular consideration is given to press stacking paper using this recirculation path. Therefore, when paper processing is performed with a post-processing device connected downstream of this device, if the post-processing time allowable on the processing device side is exceeded, it is eventually necessary to suppress paper conveyance on the image forming device side. There is. As a result, it was not possible to prevent a decrease in productivity.

  Therefore, the problem to be solved by the present invention is to prevent a decrease in productivity due to pre-stacking without increasing the size of the apparatus.

In order to solve the above problems, according to one embodiment of the present invention, a first transport unit that transports a sheet along a first transport path and a sheet transported by the first transport unit are received and transported to a subsequent stage. A second transporting means, a second transport path for transporting the paper transported along the first transport path in a transport direction, and transporting the fed paper to a subsequent stage, and the second Connecting the opposite side of the transport path to the first transport path upstream of the first transport means, transports the paper from the second transport path to the first transport path, and circulates it. And a circulating conveyance path capable of conveying the sheet, wherein the second conveying unit is rotated in the reverse direction while the sheet is held by the first conveying unit and the second conveying unit. A first pair of conveying members that folds the sheet, and from the second conveying path, Characterized in that it discharges the sheet that has been folded by the conveying member pairs.

According to one embodiment of the present invention, productivity reduction due to prestacking can be prevented without increasing the size of the apparatus. Problems, configurations, and effects other than those described above will become apparent from the following description of embodiments.

1 is a diagram illustrating a schematic configuration of an image forming system according to an embodiment of the present invention. It is a figure which shows schematic structure of the image forming system which concerns on other embodiment. It is a figure which shows the folding mechanism of the folding processing apparatus in FIG.1 and FIG.2. 2 is a block diagram showing a control configuration of the image forming system in the present embodiment. FIG. FIG. 9 is an operation explanatory diagram illustrating an operation of transferring a sheet received from upstream without performing folding processing to the downstream as it is, and illustrates an initial state before the sheet is conveyed from the image forming apparatus side. FIG. 6 is an operation explanatory diagram illustrating a state immediately after the first paper detection sensor detects the leading edge of the paper conveyed from the state of FIG. 5 from the image forming apparatus side. It is operation | movement explanatory drawing which shows the state currently conveyed by the 1st and 2nd conveyance member from the state of FIG. It is operation | movement explanatory drawing shown about the operation | movement of Z folding, and is operation | movement explanatory drawing which shows the state immediately after reversing the 2nd conveyance member. It is operation | movement explanatory drawing which shows a state when performing a 1st folding with the 2nd and 3rd conveyance roller from the state of FIG. It is operation | movement explanatory drawing which shows the state which is conveying the 2nd conveyance path W2 by the 3rd conveyance member from the state of FIG. FIG. 11 is an operation explanatory diagram showing a state when the third conveying member is reversed from the state of FIG. 10 and the second folding is performed by the second and fourth conveying rollers R3 and R5. FIG. 9 is an operation explanatory diagram illustrating an operation of prestack processing, and shows an initial state before a sheet is conveyed from the image forming apparatus side. FIG. 13 is an operation explanatory diagram illustrating a state immediately after the first sheet detection sensor detects the leading edge of the sheet conveyed from the state of FIG. 12 from the image forming apparatus side. It is operation | movement explanatory drawing which shows a state when it is conveyed by the 2nd conveyance path via the connection path | route from the state of FIG. 13, and goes to a circulation conveyance path. It is operation | movement explanatory drawing which shows the state conveyed by the 1st conveyance path via the circulation conveyance path from the state of FIG. 14, and abutted against the 1st conveyance member. FIG. 16 is an operation explanatory diagram illustrating a state in which the leading edge of the succeeding paper comes into contact with the first transport member from the state of FIG. FIG. 17 is an operation explanatory diagram illustrating a state in which the leading ends of the preceding paper and the succeeding paper are overlapped and transported through the first transport path from the state of FIG. 16. FIG. 9 is an operation explanatory diagram illustrating the operation of each unit when folding in half, showing an initial state before the sheet is conveyed from the image forming apparatus side. FIG. 19 is an operation explanatory diagram illustrating a state immediately after the first sheet detection sensor detects the leading edge of the sheet conveyed from the image forming apparatus side from the state of FIG. It is operation | movement explanatory drawing which shows the state currently conveyed by the 1st and 2nd conveyance member from the state of FIG. It is operation | movement explanatory drawing which shows the state immediately after reversing the 2nd conveyance member from the state of FIG. It is operation | movement explanatory drawing which shows a state when folding with the 2nd and 3rd conveyance roller from the state of FIG. It is operation | movement explanatory drawing which shows a state when it guides to the circulation conveyance path side by the 3rd conveyance member from the state of FIG. It is operation | movement explanatory drawing which shows a state when it sends to the 1st conveyance member of a 1st conveyance path through the circulation conveyance path by the 3rd conveyance member from the state of FIG. It is operation | movement explanatory drawing which shows the state conveyed in the 1st conveyance path to the downstream by the 1st and 2nd conveyance member from the state of FIG. It is explanatory drawing which shows the folding operation | movement of 3 inside. It is explanatory drawing which shows folding operation | movement of an outer three fold It is explanatory drawing which shows folding operation of 4 folds. It is a figure which shows the adjustment screen of the number of pre-stacks of the operation panel at the time of pre-stacking using a 2nd conveyance path and a circulation conveyance path. It is a flowchart which shows the process sequence of the pre-stack process at the time of no folding process. It is a flowchart which shows the process sequence of the pre-stack process at the time of folding process.

  The present invention is characterized in that the transport path used in the folding process is a recirculation path, and sheets are pre-stacked on the transport path.

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

  FIG. 1 is a diagram showing a schematic configuration of an image forming system according to an embodiment of the present invention. In FIG. 1, an image forming system 1 according to the present embodiment basically includes an image forming apparatus 200, a folding processing apparatus 100, and a post-processing apparatus 300. The folding processing apparatus 100 is provided between the front-stage image forming apparatus 200 and the rear-stage post-processing apparatus 300. A sheet on which an image is formed by the image forming apparatus 200 is conveyed to the folding processing apparatus 100, subjected to a predetermined folding process by the folding processing apparatus 100, and further sent to the post-processing apparatus 300. In the post-processing device 300, post-processing such as alignment processing, binding processing, or bookbinding processing is performed on the folded paper or the paper that is not pressed.

  FIG. 2 is a diagram illustrating a schematic configuration of an image forming system according to another embodiment. In FIG. 2, the folding processing apparatus 100 is a so-called in-body installation type provided in a paper discharge unit in the image forming apparatus 200. In the image forming system 1 shown in FIG. 2, the folding processing apparatus 100 is installed in the in-body sheet discharge unit 200 a of the image forming apparatus 200 and can be accommodated within the installation area of the image forming apparatus 200. Compared to the first embodiment, the size is greatly reduced.

  FIG. 3 is a diagram illustrating a folding mechanism of the folding processing apparatus 100 in FIGS. 1 and 2.

  The folding apparatus 100 includes two conveyance paths, a first conveyance path W1 and a second conveyance path W2, and the first to third plurality of conveyance members F1, F2 along the two conveyance paths W1, W2. , F3 are arranged. The second transport member F2 is disposed so as to sandwich the first transport path W1 and the second transport path W2, and has a function of folding and transferring the paper P from the first transport path W1 to the second transport path W2.

  The first conveying member F1 is composed of a first conveying roller pair R1. The second transport member F2 includes first to fourth transport rollers R2, R3, R4, and R5. The 3rd conveyance member F3 is comprised from 2nd conveyance roller pair R6. The first and second transport roller pairs R1 and R6 (first transport member F1 and third transport member F3) are driven by first and third drive motors M1 and M3, respectively, to apply a transport force to the paper P.

  The first conveying roller pair R1 is provided on the entrance side of the folding processing apparatus 100 in the first conveying path W1, receives paper from the preceding image forming apparatus 200, is driven by the first drive motor M1, and is downstream of the folding processing apparatus 100. The sheet P is conveyed to the side.

  Although not shown, the second transport path W2 is joined to the downstream side (sheet discharge side) end W2a in the paper transport direction in the downstream side of the first transport path W1 in the present embodiment, and the upstream end in the paper transport direction. The part W2b joins the upstream side of the first transport roller pair R1 via the circulation transport path W2d. And the 1st conveyance path W1 is connected with the 2nd conveyance path W2 by the communication path W2c in the installation location of the 2nd conveyance member F2 downstream of the 1st conveyance roller pair R1.

  In the second conveying member F2, the first and second conveying rollers R2, R3 are opposed to each other with the first conveying path W1 interposed therebetween, and a second nip N2 is formed therebetween. Further, the second and third transport rollers R3, R4 are arranged to face each other between the first transport path W1 and the second transport path W2, and a third nip N3 is formed between them. The path guided by the third nip N3 functions as a communication path W2c that guides the sheet from the first transport path W1 to the second transport path W2. Further, the second and fourth transport rollers R3 and R5 face each other with the second transport path W2 interposed therebetween, and a fourth nip N4 is formed between them.

  The first to fourth transport rollers R2 to R5 are driven by a second drive motor M2 that drives the second transport roller R3. That is, the second drive member F2 is driven by the second drive motor M2. The second drive motor M2 can rotate in both forward and reverse directions. By changing the direction of rotation, the second drive motor M2 conveys the paper P and performs a folding process. Note that the second transport member F2 may be formed of not only a pair of transport rollers but also an adhesive transport roller pair or a suction belt.

  In the second conveying member F2, the second conveying roller R3 is a driving conveying roller, and the first, third, and fourth conveying rollers R2, R4, and R5 are driven conveying rollers that rotate in contact with the second conveying roller R3, respectively. It is. The second conveying roller R3 and the third conveying roller R4 constitute a first folding means, and the second conveying roller R3 and the fourth conveying roller R5 constitute a second folding means.

  The first, third and fourth transport rollers R2, R4, R5 are respectively given elastic force toward the second transport roller R3 by first to third compression springs (elastic members) S2, S3, S4, respectively. Contact with the second transport roller R3 is maintained. Thereby, the driving force is obtained from the second transport roller R3, and the other three transport rollers R2, R4, R5 are driven.

  The first conveying roller pair R1 includes a driving conveying roller R1a and a driven conveying roller R1b, and a driving force is applied to the driving conveying roller R1a from the first driving motor M1. The driven transport roller R1b is given elastic force to the drive transport roller R1a side by the first compression spring S1, contacts at the first nip N1, and is driven in that state. The second conveying roller pair R6 includes a driving conveying roller R6a and a driven conveying roller R6b, and a driving force is applied to the driving conveying roller R6a from the third driving motor M3. The driven conveyance roller R6b is given an elastic force to the drive conveyance roller R6a side by the fifth compression spring S5, contacts at the fifth nip N5, and is driven in that state.

  The first sheet detection sensor SN1 is immediately before the first conveyance roller pair R1 in the first conveyance path W1, and the second sheet detection sensor SN2 is immediately after the first and second conveyance rollers R2 and R3 nips. A third sheet detection sensor SN3 is disposed in the immediate vicinity of the second conveyance roller pair R6 on the conveyance path W2 on the side away from the fourth conveyance roller R5. The first sheet detection sensor SN1 functions as an entrance sheet detection sensor, and the second sheet detection sensor SN2 functions as a discharged sheet detection sensor.

  Further, a branching claw B is disposed immediately before the second nip N2 of the second conveying member F2 in the first conveying path W1 in the sheet conveying direction. The branching claw B moves to the position retracted from the first conveyance path W1 when the paper P is guided to the second nip N2, and the folding guide position shown in FIG. 3 when the paper P is guided to the third nip N3. Move to each. The branch claw B can be moved to the two positions by a solenoid, for example. Note that a drive mechanism including a motor, a gear, a cam and the like can be used instead of the solenoid.

  FIG. 4 is a block diagram showing a control configuration of the image forming system in the present embodiment.

  In FIG. 4, the folding processing apparatus 100 includes a control circuit on which a microcomputer having a CPU 100a, an I / O interface 100b, and the like is mounted. Signals from the CPU of the image forming apparatus 200, each switch of the operation panel 201, and each sheet detection sensor (not shown) are input to the CPU 100a via the communication interface 100c. The CPU 100a executes predetermined control based on a signal input from the image forming apparatus 200 side. Further, the CPU 100a controls the drive of the solenoid and the motor via the driver and the motor driver, and acquires the paper detection sensor information in the apparatus from the interface. Further, for example, the motor driver is controlled by the motor driver via the I / O interface 100b for the control target, and the paper detection sensor information is acquired from the paper detection sensor. The control is executed based on the program defined by the program code while the CPU 100a reads the program code stored in the ROM (not shown), develops it in the RAM (not shown), and uses the RAM as a work area and a data buffer. Is done.

  In the present embodiment, the folding mechanism shown in FIG. 3 can be used to perform two-fold, Z-fold, inner three-fold, outer three-fold, and four-fold. Each folding operation is instructed and executed by the CPU 100a shown in FIG.

  Hereinafter, the operation of each unit according to the type of folding will be described with reference to the drawings.

  FIG. 5 to FIG. 7 are operation explanatory views showing the operation of transferring the sheet received from the upstream without performing the folding process to the downstream as it is.

  FIG. 5 shows an initial state before the sheet is conveyed from the image forming apparatus 200 side. When the leading end P01 of the sheet P conveyed from the image forming apparatus 200 side is detected by the first sheet detection sensor SN1 as shown in FIG. 6 from the state of FIG. 5, the first conveying roller pair R1 which is the first conveying member F1. Starts rotating. When the leading edge P01 of the paper P enters the first nip N1 of the first transport roller pair R1, the paper P is transported to the second transport member F2 side. At that time, the branching claw B is kept retracted from the first conveyance path W1.

  Then, the second drive motor M2 is driven at the time when the second drive motor M2 is transported to the point immediately before the second nip N2 between the second transport roller R3 and the third transport roller R4, and the first and second transport rollers R2 and R3 are moved to the arrows shown in FIG. Rotate in the direction. Then, the sheet P is transported to the downstream side as it is and delivered to the downstream machine.

  Note that whether or not the sheet has been conveyed just before the second nip N2 can be determined from, for example, the number of driving steps of the first drive motor M1 that drives the first conveying member F1. In order to perform such control, in the present embodiment, the first to third drive motors M1, M2, M3 are constituted by stepping motors. Each drive motor M1, M2, M3 can also be comprised by motors other than a stepping motor. In that case, a control method corresponding to the employed motor type is taken.

  8 to 11 are operation explanatory views showing the Z-folding operation.

  Z-folding is the folding that is the basis of the folding process. This Z-folding is the same as the operation shown in FIGS. 5 to 7 until the first and second transport path rollers R2 and R3 receive the paper on which the image is formed. Then, as shown in FIG. 7, after the first and second transport rollers R2 and R3 start to rotate in the direction of the arrows in the drawing, in order to set the folding position, the amount of protrusion from the position of the second paper detection sensor SN2 ( First projection amount) Δ1 is determined. In Z-folding, the sheet P is folded outward (first fold) from the front end P01 of the sheet P in the sheet conveyance direction at a quarter position of the entire length of the sheet, and is folded inward (second fold) at a position ½ of the total length. This position is set by the CPU 100a calculating the first protrusion amount Δ1 or referring to the ROM table.

  That is, the sheet P is transported from the position where the leading end P01 of the sheet P is detected by the second sheet detecting sensor SN2 until the leading end P01 of the sheet P reaches the first protrusion amount Δ1. The first protrusion amount Δ1 is determined from the sheet length and the folding method, and is determined by the rotation amount of the first transport roller R2. When the leading edge P01 of the sheet P reaches the protrusion amount Δ1, the second conveying member F2 (third conveying roller R3) is temporarily stopped. At that time, before the stop, control is performed so that the vehicle is decelerated in the same manner as in the case of folding in half and stopped accurately at the position of the first protrusion amount Δ1. Next, with the first transport member F1 rotated in the transport direction, the second transport member F2 (second transport roller R3) is rotated in the reverse direction with respect to the transport direction up to FIG. 7 (FIG. 8). The first protrusion amount Δ1 can also be determined based on the transport amount of the first transport member F1 from the position of the first paper detection sensor SN1.

  The sheet P is transported in the reverse direction by the reverse rotation of the second transport member F2 (second drive motor M2). On the other hand, since the first conveying member F1 rotates in the direction continued from FIG. 6 and conveys the paper P, bending is formed in the third nip N3 as in the case of folding in two (FIG. 8). This bending enters the third nip N3 and the first folding is performed. Thereby, the first fold line P03 is formed. The first folded paper P is transported to the second transport path W2 as shown in FIG.

  The sheet P is transported along the downward gradient of the second transport path W2, and is sandwiched and transported by the fifth nip N5 of the second transport roller pair R6 that has started rotating in the direction of the arrow as shown in FIG. Is done. Then, when the leading end (first fold line P03) of the paper P is detected by the third paper detection sensor SN3 and reaches a position protruding from the position by the second protrusion amount Δ2, as shown in FIG. The conveyance member F3 (second conveyance roller pair R6: third drive motor M3) stops and starts reverse rotation. Note that the second protrusion amount Δ2 can also be set as a protrusion amount from the fifth nip N5.

  Similar to the first protrusion amount Δ1, the second protrusion amount Δ2 is determined from the sheet length and folding method, and is determined by the rotation amount of the second transport roller pair R6 (the number of driving steps of the third drive motor M3). . Further, the reverse rotation of the third conveying member F3 (second conveying roller pair R6) is such that the second conveying member F2 (second and third conveying rollers R3, R4) maintains the rotation direction shown in FIGS. Executed in state. As a result, as shown in FIG. 11, the sheet P is bent by the communication path W2c on the downstream side of the third nip N3.

  When driving in the rotational direction of the second and third transport members F2 and F3 shown in FIG. 11 is continued, the deflection enters the fourth nip N4 formed by the second transport roller R3 and the fourth transport roller R5, The sheet P is transported in the direction of the end W2a on the paper discharge side of the second transport path W2. In the course of this conveyance, the second fold is applied, and a second fold P04 is formed on the paper P. The second folded paper P is further transported from the paper discharge side end W2a to the post-processing apparatus 300 in the subsequent stage through the first transport path W1. Alternatively, the paper is discharged to the paper discharge tray 400.

  In FIG. 11, the third paper detection sensor SN3 detects the passage of the rear end P02 of the paper P, and after passing through the fourth nip N4, the second and third transport members F2, F3 (second and second) The three drive motors M2, M3) stop rotating. Further, as shown in FIG. 11, the first drive motor M1 stops rotating at a timing after the first sheet detection sensor SN1 detects the trailing edge P02 of the sheet and then the trailing edge of the sheet leaves the first nip N1. . In this way, Z-folding is performed.

  12 to 17 are operation explanatory views showing the operation of the prestack processing according to the embodiment of the present invention.

  In the present embodiment, the sheets can be prestacked in addition to the folding process. The paper post-processing device 300 performs processing performed on the paper by the folding processing device 100, that is, processing other than folding processing, for example, punch processing and stapling processing.

  When stapling is performed, in most cases, a prestack mechanism is provided in the sheet post-processing apparatus 300 in order to prevent a decrease in productivity. However, the productivity is not necessarily 100 by providing the prestack mechanism as described above. % Is not kept. On the other hand, in the present embodiment, the post-processing time of the paper post-processing device 300 connected to the downstream machine is digested in the folding processing device 100 to prevent a decrease in productivity. Specifically, the circulation conveyance path W2d that connects the second conveyance path W2 and the first conveyance path W1 used during the folding process is caused to function as a recirculation path.

  When the leading end P11 of the preceding sheet (preceding sheet) P1 conveyed from the image forming apparatus 200 side is detected by the first sheet detection sensor SN1, the first conveying roller pair R1 that is the first conveying member F1 starts to rotate. . When the leading edge P11 of the preceding sheet P1 enters the first nip N1 of the first conveying roller pair R1, the preceding sheet P1 is conveyed to the second conveying member F2. At that time, the branching claw B is caused to enter the first conveyance path W1, and the preceding paper P1 is guided to the third nip N3 side.

  Then, the second driving motor M2 and the third driving motor M3 are driven at the time when the second driving motor M2 and the third driving motor M3 are transported to just before the branching claw B, and the second and third transporting rollers R3 and R4 and the second transporting roller pair 6 are moved to the arrows in FIG. Rotate in the direction. As a result, the preceding paper P1 is nipped by the third nip N3 and conveyed to the second conveying path W2. The preceding paper P1 is guided and conveyed to the circulation conveyance path W2d side along the inclination of the second conveyance path W2.

  When the leading edge P11 of the preceding paper P1 reaches the fifth nip N5 of the second conveyance roller pair 6, a conveyance force is also applied from the second conveyance roller pair 6, and as shown in FIG. Be transported. At this time, when the trailing edge P12 of the preceding paper P1 passes through the first nip N1 of the first conveying roller pair R1, the drive motor M1 is stopped. The preceding paper P1 conveyed by the second conveying roller pair R6 stops after the leading end P11 is abutted against the first nip N1 of the stopped first conveying roller pair R1. At this time, the skew correction is simultaneously performed on the preceding paper P1. This state is pre-stack completion.

  Then, as shown in FIG. 16, the leading end P21 of the next sheet (following sheet) P2 hits the first nip N1 of the first conveying roller pair R1, and the skew of the following sheet P2 is corrected, and then the first sheet P2 is corrected. The drive motor M1 starts the next drive. As a result, the leading edges P11 and P21 of the preceding sheet P1 and the next sheet P2 can be accurately superimposed. Thereafter, the prestacking process shown in FIGS. 13 to 16 is performed until the set number of prestacks is reached.

  The number of sheets to be prestacked is automatically determined by the post-processing means of the paper post-processing device 300 connected downstream. The user can also set in advance. Therefore, in the sheet post-processing apparatus 300, when the number of prestacks reaches a preset number, the branching claw B is retracted from the first transport path W1 after the leading edge is overlapped with the next sheet. This state is shown in FIG. As a result, the first transport path W1 is opened, and the prestacked sheet bundles P1 and P2 are transferred to the first and second transport rollers R2 and R3 on the downstream side, and transported to the downstream machine as they are. The

  It is also possible to stack a plurality of prestacked sheets and perform the folding process as described above. At the time of this folding, only the last process in the pre-stack mode is different. That is, the sheet is prestacked by the above-described prestacking method with “overlapping / folding set number−1” and conveyed while being overlapped with the set number of overlapping folding. Thereafter, the branching claw B is retracted from the first conveyance path W1 so that it can be delivered to the first and second conveyance rollers R2 and R3 downstream, and the folding process is performed in the same manner as a single folding process. .

  Further, the second conveyance path W2 and the circulation conveyance path w2d are used as the recirculation path, and are folded by the conveyance members F1 to F3 on the first and second conveyance paths W1 and W2 and the pressurizing means associated therewith. The sheet bundles P1 and P2 can be additionally folded.

  18 to 25 are operation explanatory views showing the operation of each part when folding in half.

  FIG. 18 shows an initial state before the sheet is conveyed from the image forming apparatus 200 side. As shown in FIG. 19 from the state of FIG. 18, the paper P is carried into the first transport path W1 from the image forming apparatus 200 side. When the first paper detection sensor (entrance paper detection sensor) SN1 detects the leading edge P01 of the paper P, the first drive motor M1 starts rotating (in the direction of arrow R1), and the paper P is the first of the first transport roller pair R1. When entering the nip N1, the paper P is transported to the second transport member F2 on the downstream side by the first transport roller pair R1. The sheet P having the leading end reached the first conveying member F2 is nipped by the second nip N2 between the first and second conveying rollers R2 and R3 and further conveyed downstream.

  When the leading edge P01 of the sheet P is detected by the second sheet detection sensor SN2, the third drive motor M3 decelerates and is conveyed to a preset third protrusion amount Δ3 corresponding to the folding in two (FIG. 20). ). When the position of the third protrusion amount Δ3, in other words, the central portion in the transport direction of the paper P reaches the position where it is folded at the third nip N3, it stops once. And the rotation of a reverse direction is started (FIG. 21). At that time, the first conveying roller pair R1 is also stopped in synchronization with the first and second conveying rollers R2 and R3, and then the sheet P is conveyed downstream in the conveying direction at the same speed as the first and second conveying rollers R2 and R3. Transport to.

  In this case, the control is not performed so that the second drive motor M2 is immediately stopped when the sheet P conveyed from the upstream side cuts the detection position of the second sheet detection sensor SN2. The second drive motor M2 is controlled so that the second drive motor M2 is stopped and reversely rotated after a time when the sheet P protrudes from the preset second sheet detection sensor SN2 by the amount of protrusion (movement amount) Δ3. Is done. The protrusion amount Δ3 is calculated by the CPU 100a, or the relationship between the paper size and the movement amount is previously tabulated and stored in the ROM, and is set according to the paper size. This setting is performed based on the data received from the image forming apparatus 200 by the CPU 100a from the image forming apparatus 200 before the job is started (before image formation on the paper P).

  When the second drive motor M2 rotates in the reverse direction, the sheet P swells to the third nip N3 side formed by the second and third transport rollers R3 and R4 in the communication path W2c (FIG. 21) and is folded at the third nip N3. Then, the process proceeds to the second transport path W2 side with the fold line P05 as the head (FIG. 22). The same control can be performed by continuing the rotation in the paper discharge direction without stopping the first transport roller pair R1.

  In the communication path 2Wc, the first transport path W1 is open on the side facing the third nip N3 and closed on the other side, so that the sheet P swells toward the third nip N3. However, to prevent jamming, the branch claw B is operated so that the direction in which the sheet P bends becomes the direction of the third nip N3 when the first and second transport rollers R2 and R3 are reversed. Yes.

  As shown in FIG. 22, the fold line P05 of the paper P folded at the third nip N3 is guided in the direction of the second transport roller pair R6 along the downward slope of the second transport path W2, and is shown in FIG. In this way, the fold is strengthened at the fifth nip N5 of the second conveying roller pair R6. Then, as shown in FIG. 24, the first transport roller pair from the upstream side of the first transport roller pair R1 in the first transport path W1 through the circulation transport path W2d connecting the second transport path W2 and the first transport path W1. It is fed into the first nip N1 of R1.

  The sheet P sent to the first nip N1 of the first transport roller pair R1 is transported in the direction of the second transport member F2 by the first transport roller pair R1. Then, as shown in FIG. 25, the sheet is transferred to the pair of first and second conveying rollers R2 and R3 of the second conveying member F2, and discharged to the subsequent stage by the first and second conveying rollers R2 and R3. At this time, the branching claw B is retracted from the first transport path W1 in order to transport the paper P in the direction of the second transport member F2.

  When the leading edge 05 of the folded paper P passes through the second nip N2 and the trailing edge P02 of the folded paper passes through the third paper detection sensor SN3, the second and third drive motors M2, M3 are turned off. Stop. When there is a next sheet, the operation from FIG. 18 is repeated, and the folded sheet is discharged to the rear stage, here, the post-processing apparatus 300 at the rear stage.

  In addition, multi-folding of two or more folds such as three folds can be realized with the same idea. For example, in the case of three folds, the amount of protrusion (movement amount) from the second paper detection sensor SN2 can be calculated based on the type of fold (two fold, three fold (inner fold, outside), four fold, etc.) and the paper size. To control. Alternatively, the relationship between the folding type and the paper size is calculated in advance and stored in the ROM table, and the CPU 100a of the folding apparatus 100 sets the protrusion amount with reference to the ROM table during folding processing, and folds the paper. Note that the type of folding and the paper size are transmitted from the image forming apparatus 200 before the folding process is started. Then, for each folding, one loop (the first conveyance path W1, the second conveyance path W2, and the circulation conveyance path W2d [the three loops correspond to the recirculation path] is performed one time at a time) Fold it in. One fold is used for one fold, and two folds are used for three and four folds.

  FIG. 26 is an explanatory view showing a procedure of three in-folds, FIG. 27 is an outer three-fold, and FIG. 28 is a four-fold.

  In the inner three-fold, as shown in FIG. 26, the first fold is performed such that a portion of 1/3 of the sheet length from the leading end P01 is folded at the third nip N3 as the first fold P03 (FIG. 26A). , (B)). After performing the first folding, the sheet returns to the first conveyance path W1 again through the second conveyance path W2 and the circulation conveyance path W2d. Then, the first and second transport rollers R2 and R3 of the second transport unit F2 feed the second fold line P04 from the third fold line P03 to a position that is 1/3 of the sheet length. Thereafter, the first and second transport rollers R2, R3 are reversed from the position so that the second fold line P04 is folded at the third nip N3 of the second and third transport rollers R3, R4.

  As a result, as shown in FIG. 26 (c), a second fold P04 is formed, with the second fold P04 as the head, through the second conveyance path W2, the circulation conveyance path W2d, and the first conveyance path W1, and on the downstream side. To the paper post-processing apparatus 300.

  In the outer three-fold, as shown in FIG. 27, the first fold is performed such that a portion of 2/3 of the sheet length from the leading end P01 is folded at the third nip N3 as the first fold P03 (FIG. 27A). , (B)). After performing the first folding, the sheet returns to the first conveyance path W1 again through the second conveyance path W2 and the circulation conveyance path W2d. Then, the first and second transport rollers R2 and R3 of the second transport unit F2 feed the second fold line P04 from the first fold line P03 to a position that is 1/3 of the sheet length. Thereafter, the first and second transport rollers R2, R3 are reversed from the position so that the second fold line P04 is folded at the third nip N3 of the second and third transport rollers R3, R4.

  As a result, a second fold P04 is formed as shown in FIG. 27 (c), and the second fold P04 and the sheet rear end P02 are set at the head, so that the second conveyance path W2, the circulation conveyance path W2d, and the first conveyance path are formed. The paper is conveyed to the downstream paper post-processing apparatus 300 through W1.

  In the fourth folding, as shown in FIG. 28, the first folding is performed so that the half of the sheet length from the leading end P01 is folded at the third nip N3 as the first folding line P06 (FIG. (B)). After performing the first folding, the sheet returns to the first conveyance path W1 again through the second conveyance path W2 and the circulation conveyance path W2d. Then, the first and second transport rollers R2 and R3 of the second transport unit F2 send the second fold line P07 from the first fold line P06 to a position that is a quarter of the sheet length (FIG. 28C). ). Thereafter, the first and second transport rollers R2, R3 are reversed from the position so that the second fold line P06 is folded at the third nip N3 of the second and third transport rollers R3, R4.

  As a result, a second fold P07 is formed as shown in FIG. 28 (d), with the second fold P07 being at the head, through the second conveyance path W2, the circulation conveyance path W2d, and the first conveyance path W1. To the paper post-processing apparatus 300.

  FIG. 29 is a diagram showing an adjustment screen for the number of pre-stacks on the operation panel when pre-stacking using the second conveyance path and the circulation conveyance path. In the present embodiment, when pre-stacking, an operation screen 201a as shown in FIG. As can be seen from FIG. 29, in this embodiment, the user can arbitrarily set the number of prestacks in the folding processing apparatus 100 from the operation panel 201.

  The adjustment of the number of prestacks is set for each size as shown in the prestack number adjustment screen 201b of FIG. Since the setting is set for each size, the adjustment value has an upper limit for each size of the paper P, and when the setting exceeds the upper limit setting, the setting value is set to the upper limit value.

  The adjustment of the number of pre-stacks is effective for pre-stacking when the folding process is not performed, and this adjustment value is not seen for the pre-stacking during the overlapping folding process. At the time of the overlap folding process, the number obtained by subtracting one from the number of overlap folding determined in advance by the system specifications is set as the maximum prestack number.

  FIG. 30 is a flowchart showing the processing procedure of the prestack processing when there is no folding processing. That is, FIG. 30 shows a processing procedure when pre-stacking with the operations shown in FIGS. When the folding processing is not performed in the folding processing apparatus 100, it is determined whether or not to perform the prestack depending on the presence or absence of the processing waiting time of the downstream machine (step S101). When there is no processing waiting time (step S101: YES), the sheet received from the upstream is directly transferred to the downstream machine (step S102).

  When there is a processing waiting time of the downstream machine (step S101: NO), the prestack adjustment value of the paper size of the conveyed paper P is compared with the current number of prestacks (step S103). Based on the comparison result, it is determined whether to perform prestack processing or to wait for paper conveyance from the image forming apparatus 200.

That is, in step S103,
If the current prestack number of the target size <the prestack upper limit value of the target size is determined, and the current prestack number of the target size has reached the prestack upper limit value of the target size (step S103: NO), image formation is performed. The apparatus 200 is caused to wait for the processing waiting time of the sheet post-processing apparatus 300 described later (step S104).

  On the other hand, if the current number of pre-stacks of the target size does not reach the pre-stack upper limit value of the target size in step S103, the pre-stack processing shown in FIGS. 12 to 17 is executed in the folding processing apparatus 100. . Note that after the prestack process is executed in step S105, it is determined whether or not the prestacked sheet is the final sheet of the copy (step S106). If the sheet is the final sheet, the process ends as it is. If it is not the final sheet, the processes of step S101 and step S103 are repeated until the pre-stack upper limit value of the target size is reached. When the processing waiting time of the downstream machine is exhausted, the process proceeds to step S102, or when the upper limit is reached, the process proceeds to step S104 and the process is finished.

  FIG. 31 is a flowchart showing a processing procedure of prestack processing when folding processing is performed.

  In the case of performing the folding process, the process changes depending on whether the sheet is folded or a plurality of sheets are overlapped. Therefore, it is first checked whether the sheet is folded (step S201). If the sheet is folded (step S201: YES), the designated folding process is executed for the one sheet (step S205). If overfolding (step S201: NO), prestack processing is performed until the final sheet arrives (steps S202, S203, S204), and the prestacked sheet bundle and the final sheet are overlapped to perform folding processing. This is performed (step S205).

  After the folding process, the current number of additional folds is compared with the number of additional folds by paper type and paper thickness (step S206). After the folding process, the paper folded according to the number of additional foldings set in advance for each paper type paper thickness is conveyed on the recirculation path (second conveyance path W2 → circulation conveyance path W2d → first conveyance path W1). To do. This one loop is incremented and counted as one folding, and the loop is performed for the set number of times (step S206: YES, step S208). When the loop is completed for the set number of times (step S206: NO), the folded sheet is transferred to the downstream machine (step S207), and the process is terminated.

  As described above, according to the present embodiment, the following effects can be obtained.

1) A first transport member F1 (first transport unit) that transports the paper P along the first transport path W1 (first transport path) and the paper P transported by the first transport member F1 are received. A folding device 100 (paper processing device) having a second transport member F2 (second transport means) transported to the subsequent stage, in which the paper P transported along the first transport path W1 is transported And a second transport path W2 (second transport path) for transporting the fed paper P to the subsequent stage (paper post-processing apparatus 300), and upstream of the second transport path W2 in the paper transport direction. The end W2b (on the opposite side) and the first conveyance path W1 upstream from the first conveyance member F1 are connected, and the sheet can be conveyed from the second conveyance path W2 to the first conveyance path W1 and circulated for conveyance. A recirculation path in the folding device 100. It is possible to perform the pre-stack Te. Thereby, it is possible to prevent a decrease in productivity due to the prestack without increasing the size of the apparatus.

2) In a state where the sheet is held by the first conveying member F1 (first conveying unit) and the second conveying member F2 (second conveying unit), the second conveying member F2 is rotated in the reverse direction to fold the sheet. Since the second and third transport rollers R3 and R4 (first transport member pair) are provided and the paper P folded by the second and third transport rollers R3 and R4 is discharged from the second transport path W2, it is easy. A folding process can be performed on a sheet with a simple configuration.

3) The preceding paper P1 passes through the circulation transport path W2d and hits the first transport member F1, the subsequent paper hits the first transport member F1, and the first transport member F1 is driven to drive the preceding and following papers. Since the sheet is conveyed with its leading edge overlapped, the pre-stacking process can be performed using the circulation conveyance path W2d.

4) Since the process of carrying by overlapping is executed a plurality of times, a plurality of pre-stacks can be performed. Thereby, it is possible to increase the waiting time until the process is completed in the subsequent stage.

5) Since the number of processes to be carried in an overlapping manner can be changed according to the subsequent process, the most efficient prestack process can be performed.

6) Since the operation screen 201a (setting unit) for setting the number of processes to be carried in an overlapping manner is provided from the operation panel 201 (operation display panel), the user can easily set the number of prestacks from the operation panel 201. Can do. As a result, it is possible for the user to perform arbitrary prestack processing other than automatically by the machine according to the paper type, paper size, and the like.

7) After carrying out the overlapping and carrying process a plurality of times, the paper is held by the first carrying member F1 and the second carrying member F2 in a state where the paper is piled up, and the second carrying member F2 is rotated in the reverse direction. Therefore, it is possible to perform a folding process in which a plurality of sheets are folded.

8) When the second conveying member F2 is rotated in the reverse direction, the protrusion amounts Δ1, 3 from the second sheet detection sensor SN2 (second conveying means) are set according to the sheet size and the sheet folding type. It is possible to cope with various folding processes.

9) Since the number of recirculations that circulate through the recirculation path including the second conveyance path W2, the circulation conveyance path W2d, and the first conveyance path W1 is set based on the paper type or the paper thickness, it is possible to enhance the folding. it can. As a result, the folding height can be reduced.

In the present embodiment, the sheet in the claims is P in the present embodiment, the first transport path is the first transport path W1, the first transport means is the first transport member F1, and the second transport means is the first transport path. 2 on the conveying member F2, the sheet processing apparatus on the folding apparatus 100, the latter stage on the sheet post-processing apparatus 300, the opposite side on the upstream side W2b in the sheet conveying direction, the circulation conveyance path on the reference sign W2d, and the recirculation path Is a path consisting of the second transport path W2 → circulation transport path W2d → first transport path W1, the first transport member pair is the second transport roller R3 and the third transport roller R4, and the operation display panel is the operation panel 201, the setting means is on the operation screen 201a, the protrusion amounts are Δ1 and Δ3, the image forming system is a system including the image forming apparatus 200, the folding apparatus 100, and the sheet post-processing apparatus 300.
Each corresponds.

  Furthermore, the present invention is not limited to the above-described embodiments, and various modifications can be made without departing from the spirit of the present invention, and all the technical matters included in the technical idea described in the claims are all included. The subject of the present invention. The above embodiment shows a preferable example, but those skilled in the art can realize various alternatives, modifications, variations, and improvements from the contents disclosed in this specification, These are included in the technical scope described in the appended claims.

DESCRIPTION OF SYMBOLS 100 Folding device 200 Image forming apparatus 201 Operation panel 201a Operation screen 300 Paper post-processing device F1 1st conveyance member F2 2nd conveyance member P Paper R3 2nd conveyance roller R4 3rd conveyance roller W1 1st conveyance path W2b Paper conveyance End on the upstream side in the direction W2d Circulation conveyance path Δ1, Δ3 Projection amount

JP-A-4-226263 JP 2004-10271 A

Claims (7)

First conveying means for conveying the paper along the first conveying path;
A second conveying means for receiving the paper conveyed by the first conveying means and conveying it to the subsequent stage ;
A second transport path for transporting the paper transported along the first transport path in a transport direction and transporting the fed paper to a subsequent stage;
The second conveyance path is connected to the opposite side of the second conveyance path and the first conveyance path upstream of the first conveyance means, and the sheet is conveyed from the second conveyance path to the first conveyance path. A circulating conveyance path that can be circulated and conveyed;
A paper processing apparatus having
A first conveying member pair configured to fold a sheet by rotating the second conveying unit in a reverse direction while holding the sheet by the first conveying unit and the second conveying unit;
A sheet processing apparatus that discharges a sheet folded by the first conveyance member pair from the second conveyance path . First conveying means for conveying the paper along the first conveying path;
A second conveying means for receiving the paper conveyed by the first conveying means and conveying it to the subsequent stage;
A second transport path for transporting the paper transported along the first transport path in a transport direction and transporting the fed paper to a subsequent stage;
The second conveyance path is connected to the opposite side of the second conveyance path and the first conveyance path upstream of the first conveyance means, and the sheet is conveyed from the second conveyance path to the first conveyance path. A circulating conveyance path that can be circulated and conveyed;
A paper processing apparatus having
The preceding sheet is abutted against the first conveying means through the circulation conveying path, the succeeding sheet is abutted against the first conveying means, and the first conveying means is driven to drive the preceding and succeeding sheets. The process of transporting the paper with the leading edge overlapped is executed multiple times,
After performing the overlapping and transporting process a plurality of times, the sheet is held by the first transport unit and the second transport unit in a state where the sheets are stacked, and the second transport unit is rotated in the reverse direction. A paper processing apparatus characterized in that the paper is folded . The sheet processing apparatus according to claim 2 ,
The sheet processing apparatus according to claim 1, wherein the number of times of the overlapping and transporting process is changed according to a subsequent process. The sheet processing apparatus according to claim 2 ,
A sheet processing apparatus, comprising: a setting unit configured to set the number of processes to be carried in a superimposed manner from an operation display panel . The sheet processing apparatus according to claim 1 or 2 ,
When the second transport unit is rotated in the reverse direction, a projection amount from the second transport unit is set according to a paper size and a folding type of the paper. The sheet processing apparatus according to claim 1 or 2 ,
The sheet processing apparatus , wherein the number of recirculations for circulating the recirculation path including the second transport path, the circulation transport path, and the first transport path is set based on a paper type or a paper thickness . An image forming system comprising the sheet processing apparatus according to claim 1 .