JP2020117406A - Sheet processing apparatus and image forming system - Google Patents

Abstract

To prevent a duplicate fold from arising in a second sheet folding process when the folding process is performed by a nip-reverse method.SOLUTION: A sheet processing apparatus includes: a first folding roller pair 2 that folds a sheet P; a forward-reverse roller pair 3 that conveys downstream the sheet P folded by the first folding roller pair 2; and a second folding roller pair 4 that further folds the sheet P folded by the first folding roller pair 2. The forward-reverse roller pair 3 is rotatable in a forward-reverse direction when driven for conveying, and when not driven, it is locked in one rotation direction but rotatable in the other rotation direction.SELECTED DRAWING: Figure 17

Description

The present invention relates to a sheet processing apparatus and an image forming system, and particularly to a sheet-shaped recording medium (referred to as “sheet” in the present specification) such as a sheet, a transfer sheet, a printing sheet, an OHP sheet, etc., which has been carried in. The present invention relates to a sheet processing apparatus that performs a folding process, and an image forming system including the sheet processing apparatus and an image forming apparatus such as a copying machine, a printer, a facsimile, and a digital multi-function peripheral.

As a sheet processing apparatus that performs a folding process on a sheet conveyed from an image forming apparatus, for example, a technique disclosed in Japanese Patent Laid-Open No. 2006-117383 (Patent Document 1) is known. In this technique, a first stop member that can move to a position provided in a second conveyance path to stop the leading edge of the paper, a first conveyance roller that forms a fold by sandwiching the bending of the paper in the first stop member, and a first conveyance roller A pair of transport rollers formed of two transport rollers, a second stop member capable of moving to a position provided on the first transport path to stop the sheet passing through the pair of transport rollers, and the second stop member. It has a pair of conveying rollers formed by a third conveying roller and a second conveying roller that sandwiches the bending of the sheet and forms a fold, and forms a fold by controlling the stop position of the second stop member 10. It is characterized by a sheet processing device.

This technique is provided with a dedicated path and a stopper branched from the conveyance path that conveys the paper conveyed from the upstream device to the downstream device to perform the folding process, and the so-called front end abutting and folding that abuts the leading end of the paper. The processing is performed. That is, in the folding process, the sheet is brought into contact with the stopper through this dedicated path to adjust the folding position and form the bend, and the formed bend is nipped in the folding portion to be folded.

On the other hand, the technology described in, for example, Japanese Patent Laid-Open No. 2007-277006 (Patent Document 2) is also known. This technique relates to a method of folding a medium with a folding device, including a rotatable folding cylinder, a first rotatable pressing member that engages with the folding cylinder to form a first folding pinch, A folding device including a second rotatable pressing member that engages with the stacking cylinder to form a second folding pinch, and a folding device that includes a medium feeding unit feeds the medium with the first pinch and the second pinch. The medium is directed toward the intermediate cylinder, and the medium is directed into the first pinch by rotating the cylinder in the first direction to form slack in the medium between the feeding means and the cylinder, and the cylinder is opposed to the first direction. It is characterized in that the slack is moved into the second pinch and folded by rotating in the second direction.

That is, in the related art, as a method of folding, when receiving a sheet on which an image is formed and performing folding processing such as tri-folding and Z-folding, the operation is performed according to the sheet size, as disclosed in Patent Document 1 above. A method of adjusting the folding position by abutting the leading edge of the sheet on a possible sheet abutting member (hereinafter referred to as a stopper method), and folding by only adjusting the transport amount by a transporting unit as disclosed in Patent Document 2. Two methods of position adjustment (hereinafter, referred to as a pinching and reversing method) are generally used.

In the stopper method described in Patent Document 1, the tip of the folded portion of the sheet is abutted against the stopper, and the sheet portion on the first folding side formed during the first folding processing during the second folding processing. (Peller part) is always stopped. For this reason, after the bending of the sheet that occurs during the second folding process is nipped by the second folding roller pair, the sheet portion (peller portion) on the first folding side starts to move after the bending is eliminated, and thus the box folding Pc hardly occurs. However, since it is necessary to have a mechanism for moving the sheet leading end abutting member according to the sheet length, and an installation space for this mechanism is essential, it is difficult to downsize the apparatus.

On the other hand, the pinching and reversing method described in Patent Document 2 adjusts the folding position only by adjusting the carry amount, and is therefore excellent in terms of downsizing. However, when performing the second sheet folding processing such as tri-folding or Z-folding in which the sheet folding processing is performed twice, the upstream side conveying means (hereinafter, referred to as a first folding roller pair) and the downstream side conveying means (hereinafter, the normal sheet conveying means). It is necessary to convey the reverse rotation roller pair) in opposite directions to form a bend in the sheet. In this case, the first folding roller pair conveys the sheet in the downstream direction, and the forward/reverse rotation roller pair conveys the sheet in the upstream direction. Then, the second folding process is performed on the bent sheet of the second folding roller pair located downstream of the forward/reverse rotation roller pair. At that time, there are cases where two folds are formed, which is called a box fold or a box fold.

28 to 31 are explanatory views showing the mechanism of occurrence of box breakage. At the time of the second paper folding processing such as tri-folding and Z-folding in which the paper folding processing is performed twice, the first folding roller pair 2 and the forward/reverse rotation roller pair 3 are in opposite directions (the first folding roller pair 2 is in the downstream direction). Further, the forward/reverse rotation roller pair 3 conveys the sheet P in the upstream direction, forms the bend Pt1 on the sheet P, and the second folding roller pair 4 performs the second folding process. Therefore, due to the conveyance of the forward/reverse rotation roller pair 3, the sheet portion (peller portion) P1a on the first folding side including the leading edge P1 of the sheet P formed during the first folding process does not have the bending Pt2 of the second folding portion. In addition, it may be drawn into the nip of the second folding roller pair 4 (FIG. 29). When the second folding process is performed in this state (FIG. 30), a so-called box fold Pc in which two folds Pc1 and Pc2 are formed occurs (FIG. 31).

In order to prevent the box fold Pc from occurring, when the leading end P1 of the sheet P formed during the first folding process is stopped before the nip of the second folding roller pair 4 (the forward/reverse rotation roller pair 3 is stopped). (FIG. 32 ), the second folding roller pair 4 and the forward/reverse rotation roller pair 3 pull the paper P at the moment when the bending Pt2 of the second folding portion disappears (FIG. 33 ). Therefore, the forward/reverse rotation roller pair 3 may be rotated at the moment when the bending Pt2 of the second folding portion disappears to cancel the pulling. However, due to the problem of inertia, it is not realistic in terms of dynamics and control to rotate the forward/reverse rotation roller pair 3 as described above so as to eliminate the tension, and the paper P in such a mechanism is not practical. It is difficult to eliminate the tension between them.

Therefore, the problem to be solved by the present invention is to prevent the box from being folded at the time of the second paper folding processing when the folding processing is performed by the sandwiching and inverting method.

In order to solve the above problems, the present invention relates to a first conveying member pair that folds a sheet, a second conveying member pair that conveys the sheet folded by the first conveying member pair downstream, A third conveying member pair that further folds the sheet folded by one conveying member pair, and the second conveying member pair is capable of forward and reverse rotation when conveying is driven, and one rotation when not being driven. It features a sheet handling device that is locked in one direction and rotatable in the other direction of rotation. The problems, configurations, and effects other than the above will be clarified in the following description of the embodiments.

According to the present invention, it is possible to prevent box breakage during the second sheet folding process when performing the folding process by the sandwich reversal method.

FIG. 1 is a diagram illustrating a schematic configuration of an image forming system according to a first exemplary embodiment of the present invention. 6 is a diagram showing a schematic configuration of another form of the image forming system in Embodiment 1. FIG. It is a figure which shows the folding mechanism of the folding processing apparatus in FIG. 1 and FIG. 3 is a block diagram illustrating a control configuration of the image forming system in Embodiment 1. FIG. FIG. 7 is an operation explanatory diagram illustrating an initial state before a sheet is conveyed from the image forming apparatus side. FIG. 6 is an operation explanatory diagram showing a state in which a sheet has been loaded into the first transport path from the state of FIG. 5. FIG. 7 is an operation explanatory diagram showing a state in which the leading edge of the sheet has been conveyed from the second sheet detection sensor to the first protrusion amount from the state of FIG. 6; It is operation explanatory drawing which shows the state at the time of making a crease by rotating the 2nd conveyance member pair in reverse rotation, rotating the 1st conveyance member in the conveyance direction from the state of FIG. FIG. 9 is an operation explanatory diagram showing a state in which the sheet on which the first folding is formed by the first folding roller pair is conveyed from the state of FIG. 8 to the second conveyance path. FIG. 10 is an operation explanatory diagram showing a state in which the sheet is conveyed from the state of FIG. 9 along a second conveying path, is sandwiched by a pair of forward/reverse rotation rollers, and is conveyed downstream. FIG. 11 is an operation explanatory diagram showing a state in which the forward/reverse rotation roller pair is reversed from the state of FIG. 10 and is conveyed to the second folding roller pair side. FIG. 12 is an operation explanatory view showing a state in which the second folding roller pair performs second folding from the state of FIG. 11 and the sheet is conveyed to the downstream side. 6 is a flowchart showing a control procedure of the operation of each unit at the time of Z-folding. It is a figure which shows notionally the structure of the drive part main body of the normal/reverse rotation roller pair which has a play (idling area|region). It is an explanatory view of an operation principle showing a state when a pair of forward and reverse rotation rollers starts to rotate when there is no play in the idling region. FIG. 16 is an explanatory diagram of an operation principle showing a state in which a predetermined amount of paper is conveyed from the state of FIG. 15 and the forward/reverse roller pair is reversely rotated. FIG. 9 is an explanatory diagram of an operation principle showing that it is easy for the drive member to idle and pull out the sheet when the leading edge of the sheet is sandwiched by the nip of the second folding roller pair and pulled. FIG. 7 is an operation explanatory diagram showing that the sheet bending portion is nipped by the second folding roller pair, excess bending on the downstream side is eliminated, and the sheet is conveyed while being folded without bending. FIG. 6 is an operation explanatory diagram showing a state in which the forward/reverse rotation roller pair is rotating before the sheet conveyed by the first folding roller pair enters the nip of the forward/reverse rotation roller pair. FIG. 20 is an operation explanatory diagram showing a state in which the pair of forward and reverse rollers holds the sheet and further conveys the sheet to a preset position from the state of FIG. 19. FIG. 21 is an operation explanatory diagram showing a state when the sheet stop position is determined based on the detection output of the third sheet detection sensor from the state of FIG. 20. FIG. 22 is an operation explanatory diagram showing a state in which the drive member is moving in the idling region and the drive member is idling after the forward/reverse roller pair is stopped at the position shown in FIG. 21. FIG. 23 is an operation explanatory view showing a state where the drive section main body is stopped from the state of FIG. 22. FIG. 7 is an operation explanatory diagram showing a state when the forward/reverse rotation roller pair is driven after a preset time before the play of the driving member is eliminated by pulling the paper by the second folding roller pair. 6 is a schematic configuration diagram showing a forward/reverse rotation roller pair according to Embodiment 2. FIG. FIG. 10 is a diagram showing a schematic configuration of operations of a forward/reverse rotation roller pair and a drive mechanism when a motor is rotating in a forward rotation direction in Embodiment 3. FIG. 11 is a diagram showing a schematic configuration of an operation of a forward/reverse rotation roller pair and a drive mechanism when a motor is rotating in a reverse rotation direction in Embodiment 3. In the conventional nipping determination method, the first folding roller pair and the forward/reverse rotation roller pair are conveyed in opposite directions, the sheet is bent, and the second folding roller pair performs the second folding process. It is operation|movement explanatory drawing shown. FIG. 29 is an operation explanatory diagram showing a state in which the sheet portion on the first folding side is pulled into the nip of the second folding roller pair before the bending of the second folding portion disappears from the state of FIG. 28. FIG. 30 is an operation explanatory diagram illustrating a state when the second folding process is performed from the state of FIG. 29. It is operation|movement explanatory drawing which shows the state when a 2nd folding process is performed in the state of FIG. 30, and box folding has generate|occur|produced. FIG. 11 is an operation explanatory diagram showing a state in which the leading end of the sheet formed during the first folding process is stopped before the nip of the second folding roller pair in order to prevent occurrence of box folding. FIG. 33 is an operation explanatory diagram illustrating a state in which the sheet is pulled between the second folding roller pair and the forward/reverse rotation roller pair from the state of FIG. 32.

According to the present invention, when the second folding is performed, the drive unit of the forward/reverse rotation roller pair is provided with a play in which it can be conveyed upstream and downstream if it continues to rotate and is free in the other direction (upstream direction). When the reverse rotation roller is stopped, it locks in the downstream direction so that it can be easily pulled out when pulled from the upstream side, and the forward and reverse rotation roller is rotated before the play disappears, preventing box breakage. And

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

FIG. 1 is a diagram illustrating a schematic configuration of an image forming system according to a first embodiment of the present invention. In FIG. 1, the 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 image forming apparatus 200 at the front stage and the post-processing apparatus 300 at the rear stage. The sheet on which the image is formed by the image forming apparatus 200 is conveyed to the folding processing apparatus 100, is subjected to a predetermined folding processing by the folding processing apparatus 100, and is 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 showing a schematic configuration of an image forming system according to another embodiment of this embodiment. In FIG. 2, the folding processing apparatus 100 is a so-called in-body installed type provided in a paper discharge section in the apparatus of the image forming apparatus 200. In the image forming system 1 shown in FIG. 2, the folding apparatus 100 is installed in the in-body discharge section 200a of the image forming apparatus 200, and the discharge tray 400 only protrudes from the installation area of the image forming apparatus 200. The system is significantly downsized compared to the configuration of FIG.

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

The folding apparatus 100 includes two transport paths, a first transport path W1 and a second transport path W2, and a plurality of first to third transport members F1, F2 along the two transport 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 delivering the paper P from the first transport path W1 to the second transport path W2.

The first transport member F1 is composed of a first transport roller pair R1. The second transport member F2 is composed of first to fourth transport rollers R2, R3, R4 and R5. The third transport member F3 is composed of a second transport roller pair R6. The first and second transport roller pairs R1 and R6 (the first transport member F1 and the third transport member F3) are driven by the first and third drive motors M1 and M3, respectively, and impart a transport force to the paper P.

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

Although not shown, the second conveyance path W2 has an end W2a on the downstream side (sheet discharge side) in the sheet conveyance direction that merges on the downstream side of the first conveyance path W1 and an end on the upstream side in the sheet conveyance direction in this embodiment. The portion W2b joins the upstream side of the first conveying roller pair R1 or is in the open state shown in FIG. Then, at the installation location of the second transport member F2 on the downstream side of the first transport roller pair R1 of the first transport path W1, it is connected to the second transport path W2 by the communication path W2c.

In the second transport member F2, the first and second transport rollers R2 and R3 face each other across the first transport path W1 and form a second nip N2 therebetween. Further, the second and third transport rollers R3 and 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, R5 face each other across the second transport path W2 and form a fourth nip N4 therebetween.

These 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, and the paper P is conveyed and folding processing is performed by changing the rotation direction. The second transport member F2 may be configured by not only the transport roller pair but also an adhesive transport roller pair or a suction belt.

In the second transport member F2, the second transport roller R3 is a drive transport roller, and the first, third, and fourth transport rollers R2, R4, and R5 are driven transport rollers that rotate in contact with the second transport roller R3, respectively. Is. Further, the second conveying roller R3 and the third conveying roller R4 form a first folding roller pair 2, and the second conveying roller R3 and the fourth conveying roller R5 form a second folding roller pair 4.

Elastic forces are applied to the first, third, and fourth conveying rollers R2, R4, R5 toward the second conveying roller R3 side by the first to third compression springs (elastic members) S2, S3, S4, respectively. The contact with the second transport roller R3 is maintained. As a result, the driving force is obtained from the second transport roller R3, and the other three transport rollers R2, R4, R5 are driven.

The first transport roller pair R1 includes a drive transport roller R1a and a driven transport roller R1b, and a driving force is applied to the drive transport roller R1a from the first drive motor M1. The driven conveyance roller R1b is given an elastic force on the drive conveyance roller R1a side by the first compression spring S1, contacts with the first nip N1, and is driven in that state. The second transport roller pair R6 is composed of a drive transport roller R6a and a driven transport roller R6b, and a driving force is applied to the drive transport roller R6a from the third drive motor M3 in a synchronized state by a gear mechanism. The driven conveyance roller R6b is elastically applied to the drive conveyance roller R6a side by the fifth compression spring S5, comes into contact with the fifth nip N5, and is driven in that state.

In addition, the first sheet detection sensor SN1 immediately before the first conveyance roller pair R1 on the first conveyance path W1, the second sheet detection sensor SN2 immediately after the first and second conveyance rollers R2 and R3 nip, the second sheet detection sensor SN2 The third sheet detection sensor SN3 is arranged in the immediate vicinity of the side of the second transport roller pair R6, which is away from the fourth transport roller R5, of the transport path W2. 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.

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

In FIG. 4, the folding processing apparatus 100 includes a control circuit equipped with a microcomputer having a CPU 100a, an I/O interface 100b, and the like. 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 to be controlled by the motor driver via the I/O interface 100b, and the sheet detection sensor information is acquired from the sheet detection sensor.

The control is executed based on the program defined by the program code while the program code stored in the ROM (not shown) is read by the CPU 100a and expanded in the RAM (not shown) and the RAM is used as a work area and a data buffer. To be done.

In the present embodiment, the folding mechanism shown in FIG. 3 can perform two-fold, Z-fold, three-fold inner, and three-fold outer. Each of these folding operations and the rotation drive control of the rollers and the like described later are instructed and executed by the CPU 100a shown in FIG.

5 to 12 are operation explanatory views showing the outline of the operation of each part when Z-folding. FIG. 13 is a flowchart showing the control procedure of the operation of each unit.

FIG. 5 shows an initial state before the sheet is conveyed from the image forming apparatus 200 side. As shown in FIG. 6, the paper P is carried into the first transport path W1 from the image forming apparatus 200 side from the state of FIG. When the first sheet detection sensor (entrance sheet detection sensor) SN1 detects the leading edge P1 of the sheet P (step S101), the first drive motor M1 which is the first transport member F1 starts rotating (arrow R1 direction). When the paper P enters the first nip N1 of the first transport roller pair R1, the paper P is transported to the downstream second transport member F2 side by the first transport roller pair R1 (step S102). The sheet P whose front end has reached the first transport member F2 is nipped in the second nip N2 between the first and second transport rollers R2 and R3, and further transported to the downstream side.

Then, at a time point immediately before the second nip N2 between the second transport roller R3 and the third transport roller R4 is transported (step S103), the second drive motor M2 is driven to move the second transport member F1 in the direction of the arrow in FIG. To rotate (step S104). Whether or not it has been conveyed to immediately before the second nip N2 is determined based on, for example, the rotation speed of the first drive motor M1 that drives the first conveyance member F1 (or the linear velocity of the first conveyance roller pair R1) and the conveyance time. I can judge.

After the second conveying member F1 starts rotating in the direction of the arrow in FIG. 7 in step S104, the protrusion amount (first protrusion amount) Δ1 from the position of the second sheet detection sensor SN2 is determined in order to set the folding position. (Step S105). In Z-folding, the outer fold (first fold) is performed at a position ¼ of the total length of the paper from the front end P1 of the paper P in the paper transport direction, and the inner fold (second fold) is performed at a position of ½ of the total length. The position in FIG. 8 is a position where the fold line P3 is formed at a position ¼ from the front end P1 of the paper P. The setting of this position is also performed by the CPU 100a or by referring to the ROM table.

That is, the sheet P is conveyed from the position where the leading edge P1 of the sheet P is detected by the second sheet detection sensor SN2 until the leading edge P1 of the sheet P reaches the first protrusion amount Δ1. The first protrusion amount Δ1 is determined from the paper length and folding method, and is determined by the rotation amount of the first transport roller R2. When the leading edge P1 of the paper P reaches the protrusion amount Δ1 (step S105: YES), the second transport member F2 (third transport roller R3) is temporarily stopped (step S106). At that time, when the front end P1 of the paper P is detected by the second paper detection sensor SN2, the second drive motor M2 is decelerated, and the paper P is conveyed to the first protrusion amount Δ1 and stopped at that position. .. This deceleration enables highly accurate stop position control.

To set the first movement amount Δ1, the CPU 100a receives the data of the length of the paper P in the transport direction from the image forming apparatus 200 before starting the job (before forming the image on the paper P), and the data is set. The movement amount is automatically calculated based on the above, and the calculation result is used. Instead of the calculation, the relationship between the paper size and the movement amount may be tabulated in advance and stored in the ROM, and the movement amount may be set according to the paper size.

Then, while the first transport member F1 is being rotated in the transport direction, the second transport member F2 (second transport roller R3) is rotated in the reverse rotation with respect to the transport direction up to FIG. 7 as shown in FIG. 8 ( Step S107). Note that the first protrusion amount Δ1 can also be determined by the amount of conveyance of the first conveying member F1 from the position of the first sheet detection sensor SN1.

The paper 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 transport member F1 rotates in the direction continuing from FIG. 6 and transports the sheet P, the bending is formed by the effort of the third nip N3 as in the case of folding in half (FIG. 8). This flexure enters the third nip N3 to perform the first folding. As a result, the first fold line P3 is formed. The sheet P that has undergone the first folding is conveyed to the second conveying path W2 as shown in FIG.

The sheet P is conveyed along the downward slope of the second conveyance path W2, and is nipped and conveyed by the fifth nip N5 of the second conveyance roller pair R6 that starts to rotate in the arrow direction as shown in FIG. (Step S107). Then, the leading edge (first fold P3) of the sheet P is detected by the third sheet detection sensor SN3 (step S108), and when the position reached by the second protrusion amount Δ2 from that position is reached, the third conveyance member is reached. F3 (second transport roller pair R6: third drive motor M3) is stopped (step S109). Then, as shown in FIG. 11, when the sheet P is conveyed in the direction of the arrow by the second pair of folding rollers 4 (the pair of second and fourth conveying rollers R3 and R5), the driving member 3a4 moves in the idling area 3a. , Idle until the drive member 3a4 has no play (step S110).

Then, the sheet P is pulled by the second folding roller pair 4, and after the elapse of a preset time before the play of the drive member 3a4 is eliminated, the reverse rotation of the forward/reverse rotation roller pair 3 (second transport roller pair R6) is started. Yes (step S111). The operation of steps S110 and S111 and the mechanism for performing this operation will be described later. The second protrusion amount Δ2 can be set as the protrusion amount from the fifth nip N5.

The second protrusion amount Δ2 is determined from the paper length and folding method, similarly to the first protrusion amount Δ1, and the rotation amount of the forward/reverse rotation roller pair 3 (second transport roller pair R6) (driving the third drive motor M3). The number of steps). In order to perform such control, in the present embodiment, the first to third drive motors M1, M2 and M3 are stepping motors. Each of the drive motors M1, M2, M3 can be configured by a motor other than the stepping motor, for example, a DC motor. In that case, a control method according to the type of the adopted motor is adopted. For example, when a DC motor is used, the protrusion amount or drive stop timing is controlled based on the count number of encoder pulses.

When the DC motor is used to drive the forward/reverse roller pair 3, it is preferable to use the DC motor and its driving device disclosed in, for example, Japanese Patent Laid-Open No. 2012-213308. If such a DC motor is used, forward and reverse operations can be performed quickly, and productivity can be improved. Moreover, unlike stepping motors, there is no step out with respect to load fluctuations. Further, by correcting the positional deviation due to the load fluctuation and the like by the feedback control, it is possible to always rotate at an accurate position. As a result, it is possible to fold at an accurate position, and high fold quality can be guaranteed.

Further, in the reverse rotation of the forward/reverse rotation roller pair 3 (second conveying roller pair R6), the first folding roller pair 2 (second and third conveying rollers R3, R4) maintains the rotation direction shown in FIGS. 9 and 10. It is executed in the state of As a result, as shown in FIG. 11, the sheet P is bent (Pt1 described later) in the communication path W2c on the downstream side of the third nip N3.

When the rotational driving of the second and third conveying members F2 and F3 shown in FIG. 11 is continued, the bending (Pt1 described later) causes the second folding roller pair 4 (the second conveying roller R3 and the fourth conveying roller R5). ), the sheet P is conveyed in the direction of the discharge side end W2a of the second conveying path W2. In the process of this conveyance, as shown in FIG. 12, the second folding is performed to form the second fold P4 on the paper P. The sheet P that has been subjected to the second folding is further conveyed from the end W2a on the sheet discharge side to the post-processing device 300 in the subsequent stage via the first conveyance path W1. Alternatively, the paper is discharged to the paper discharge tray 400.

In FIG. 12, the third sheet detection sensor SN3 detects the passage of the trailing edge of the sheet P (step S112), and after passing through the fourth nip N4, the second and third conveyance members F2, F3 (second The second and third drive motors M2, M3) stop rotating (step S113). Further, as shown in FIG. 19, the first drive motor M1 stops rotating at the timing after the trailing edge of the sheet is separated from the first nip N1 after the trailing edge of the sheet is detected by the first sheet detection sensor SN1.

The outline of the Z-folding in the present embodiment is as described above, but in the present embodiment, in order to avoid the above-mentioned box folding phenomenon, the rotation mechanism of the forward/reverse rotation roller pair 3 or this rotation mechanism is driven. The drive mechanism is provided with preset play (idling region), and is controlled as in steps S110 and S111.

That is, the forward/reverse rotation roller pair 3 can (a) convey the paper P upstream and downstream. (b) When the forward/reverse rotation roller pair 3 is stopped, the forward/reverse rotation roller pair 3 does not move due to the strain of the paper P (the position where the paper P stops). (C) It has three basic functions of idling when the forward/reverse rotation operation of the forward/reverse rotation roller pair 3 is performed.

The function (b) is for ensuring the folding position accuracy. The function of (c) is to enable easy pulling out when pulled from the second folding roller pair 4 in order to avoid the box bending phenomenon. Because of the function (c), in this embodiment, when the forward/reverse rotation of the forward/reverse rotation roller pair 3 is performed, a play (idle region) 3a that idles in any part of the drive mechanism is provided.

FIG. 14 is a diagram conceptually showing the structure of the drive unit main body 3a1 of the forward/reverse rotation roller pair 3 having this play (idling region) 3a. As shown in FIG. 14A, the forward/reverse rotation roller pair 3 includes a drive unit body 3a1, a drive shaft 3a2, and a drive member 3a4 that transmits the drive force of the drive shaft 3a2 to the driven unit 3a3 of the roller body 3a. The member 3a4 idles in the space 3a5 in the drive unit main body 3a1 and can transmit the driving force in one direction to the drive unit main body 3a1 side when it hits the driven unit 3a3. In the other direction, the drive unit body 3a1 is locked and the drive unit body 3a1 does not rotate.

For example, in the state of FIG. 14A, when the drive shaft 3a2 rotates in the clockwise direction (arrow CW direction) in the figure, the drive unit main body 3a1 rotates in the clockwise direction (arrow CW direction) as it is. On the other hand, when the drive shaft 3a2 rotates in the counterclockwise direction (arrow CCW direction) in the state of FIG. 14A, the drive shaft 3a2 and the drive member 3a4 idle to the position shown in FIG. 14B. Even if the driving member 3a4 pushes the driven portion 3a3 to transmit the driving force, the driving portion main body 3a1 is locked in this direction, and the driving portion main body 3a1 does not rotate. Conversely, while the drive member 3a4 is located in the space 3a5 without contacting the driven part 3a3, the drive part body 3a1 idles.

That is, the drive member 3a4 is positioned in the idling region 3a until the drive shaft 3a2 rotates in the clockwise direction (arrow CW direction) in the drawing from the state of FIG. 14B and the drive member 3a4 abuts the side surface of the driven portion 3a3. Therefore, the driving force is not transmitted and the drive unit main body 3a1 does not rotate (FIG. 14(c)). Then, when there is no play in the idling region 3a and the driving member 3a4 hits the driven portion 3a3, the driving force is transmitted to the driving portion main body 3a1 side, and the driving portion main body 3a1 starts rotating (FIG. 14(d)). ).

In FIG. 14, the mechanism including the idling area 3a is provided in the drive unit main body 3a1 that drives the forward/reverse rotation roller pair 3, but it may be provided in another drive mechanism, for example, on the gear side. Furthermore, it is also possible to provide in the drive force transmission path from the drive shaft of the motor that transmits the drive force to the gear to the gear. In any case, it can be provided in the drive force transmission path from the drive source to the forward/reverse rotation roller pair 3. The forward/reverse roller pair 3 rotates in synchronization with the rotation of the drive unit main body 3a1. Therefore, the rotation operation of the drive unit main body 3a1 is equivalent to the rotation operation of the forward/reverse rotation roller pair 3.

15 to 18 are explanatory views showing the principle of the conveying operation of the forward/reverse rotation roller pair 3 having the play shown in FIG. When the sheet P is conveyed from the first folding roller pair 2, the forward/reverse roller pair 3 is rotating in the direction of conveying the sheet P to the downstream side. If the forward/reverse rotation roller pair 3 continues to rotate, the play in the idling area 3a disappears, and the forward/reverse rotation roller pair 3 starts to rotate when the play disappears, so that the sheet P can be conveyed to the downstream side (see FIG. 15). The paper P is conveyed by a predetermined amount, the forward/reverse rotation roller pair 3 is reversed (FIG. 16), and the leading end P1 of the paper P is stopped before the fourth nip N4 of the second folding roller pair 4.

At this time, the forward/reverse roller pair 3 is stopped and locked in one (downstream direction) rotation direction. As a result, the forward/reverse rotation roller pair 3 does not move due to the strain of the sheet P, and the sheet P is in a state in which it cannot be fed downstream from the stopped position. Further, in the other (upstream direction), the play amount (idle region 3a) is free in the rotational direction, so that the leading edge P1 of the sheet P is pinched by the fourth nip N4 of the second folding roller pair 4 and pulled. It can be easily pulled out (Fig. 17).

Further, when the sheet bending portion Pt1 is nipped by the second folding roller pair 4, the excessive bending Pt2 on the downstream side is eliminated, and then the sheet P is driven by the driving force of the second folding roller pair 4 so that the sheet P is rotated forward and backward. Is pulled out from. At this time, since the forward/reverse rotation roller pair 3 can idle when the paper P moves in the upstream direction, it can be pulled out without a load (FIG. 18), and the paper P is folded while the second folding roller pair 3 is not bent. 4 is conveyed.

16 to 18, the leading end P1 of the sheet P and the sheet portion (peller portion) P1a on the first folding side are guided to the nip along the guide plate 4a extending to the nip of the second folding roller pair 4. , Nipped at the nip and pulled. Therefore, no paper jam or bending occurs between the front end P1 of the paper P and the second folding roller pair 4.

19 to 24 are operation explanatory views showing an example of the operation of the forward/reverse rotation roller pair 3 in the present embodiment. The operating principle is as described with reference to FIGS.

First, before the paper P conveyed by the first folding roller pair 2 enters the nip of the forward/reverse rotation roller pair 3, the forward/reverse rotation roller pair 3 rotates in the direction of the arrow shown in FIG. The paper P is further conveyed, and the forward/reverse rotation roller pair 3 holds the paper P and then conveys it to a preset position (FIG. 20). At this time, the third paper detection sensor SN3 is provided in the peripheral position of the forward/reverse rotation roller pair 3 as described above, and the paper stop position is determined based on the detection output of the third paper detection sensor SN3 (FIG. 21). .. Instead of such a sheet detection sensor SN3, the sheet stop position can be determined by pulse count control of the third drive motor M3, encoder pulse output of a DC motor, or the like.

After stopping the forward/reverse rotation roller pair 3 at the position shown in FIG. 21, the driving member 3a4 moves in the idling area 3a and idling the driving member 3a4 (driving unit main body 3a1) until there is no play (FIG. 22). , The drive unit main body 3a1 is stopped again (FIG. 23). The idling is in the opposite direction to the rotation direction until the forward/reverse rotation roller pair 3 is stopped. Also at this time, the third sheet detection sensor SN3 (which may be separately provided) is used as in the case of the stop during the downstream conveyance shown in FIG. 21, or the pulse count control of the third drive motor M3 and the encoder of the DC motor are used. The paper stop position is determined by the output.

In this state, since the forward/reverse rotation roller pair 3 locks the rotation of the paper P in the downstream direction, the forward/reverse rotation roller pair 3 does not move due to the strain of the paper P, and the paper P is located downstream from the stopped position. I can't send it. After that, the sheet P is pulled by the second folding roller pair 4 and the forward/reverse rotation roller pair 3 is driven after a preset time period before the play of the driving member 3a4 disappears (FIG. 24). At this time, the rotation speed of the forward/reverse rotation roller pair 3 is set equal to or higher than the rotation speed of the second folding roller pair 4. As a result, the sheet P is not pulled between the second folding roller pair 4 and the forward/reverse rotation roller pair 3.

Considering the efficiency of sheet processing, it is desirable that the idling area 3a is small because the operation time of play is short.

FIG. 25 is a diagram showing a schematic configuration of the forward/reverse rotation roller pair 3 according to Example 2 of the present embodiment.

The forward/reverse rotation roller pair 3 according to the second embodiment includes first and second driving rollers 3a and 3b forming a pair, and first and second driven gears 8a and 8b driving the respective driving rollers 3a and 3b. , The first and second transmission mechanisms 9a and 9b for transmitting the driving force of the first and second driven gears 8a and 8b to the first and second drive rollers 3a and 3b, and the first driven gear 8a. It is configured to include a drive gear 7 for driving and a drive motor (not shown) for driving the drive gear 7. The second driven gear 8b meshes with the first driven gear 8a and rotates in synchronization with the rotation of the drive gear 7, and the rotational driving force is transmitted to the first and second drive rollers 3a and 3b, respectively. In this embodiment, the drive gear 7 is provided with the play mechanism shown in FIG.

The other units are configured and function in the same manner as in the first embodiment.

In the configuration in which the drive portion main body 3a1 is provided with the play (idling region) 3a as in the present embodiment, if one of the forward/reverse rotation roller pair 3 is the driven roller, there is a concern that the paper P may be rotated against the strain of the paper P. Therefore, it is necessary to prevent the paper P from rotating (locking) even if the paper P is pushed by the scraper. Therefore, in this embodiment, both of the two rollers are drive rollers. The play of the drive unit main body 3a1 may be provided in the drive gear 7 or in the upstream gear thereof.

FIG. 26 and FIG. 27 are views showing the schematic configuration of the forward/reverse rotation roller pair 3 according to Example 3 of the present embodiment.

In this embodiment, in the drive configuration of the forward/reverse rotation roller pair 3, two one-way clutch 10 and electromagnetic clutch 11 are used, and the same effect as the configuration in which the play 3a is provided in the drive unit main body 3a1 in Examples 1 and 2 is obtained. It's something I got to get.

That is, in the third embodiment, the one-way clutch 10 and the electromagnetic clutch 11 are connected to the first driven gear 8a in the second embodiment, and the drive mechanism of the motor 12 is connected to the one-way clutch 10 and the electromagnetic clutch 11. Other configurations are similar to those of the second embodiment.

With this configuration, when the motor 12 is rotating in the normal rotation direction (clockwise direction in FIG. 26: arrow CW direction), the forward/reverse rotation roller pair 3 rotates in the direction in which the paper P is conveyed to the upstream side. .. At that time, the electromagnetic clutch 11 is in the OFF state. In the stopped state, since the one-way clutch 10 is provided, when the sheet P is pulled in the upstream direction, the sheet P is rotated and is locked when the sheet P is conveyed in the downstream direction.

Further, when the motor 12 is rotating in the reverse direction (counterclockwise direction in FIG. 27: arrow CCW direction), the electromagnetic clutch 11 is turned on. As a result, the forward/reverse rotation roller pair 3 rotates in the reverse direction (the direction in which the paper P is conveyed to the downstream side), and the one-way clutch 10 side gear does not rotate. Therefore, it is possible to surely obtain the functions (a) to (c) which are the basic functions of the forward/reverse rotation roller pair 3, and it is possible to avoid the box breaking phenomenon.

The other parts are configured and function in the same manner as in the first and second embodiments.

According to the present embodiment, an operation equivalent to that of the mechanism in which the drive portion is provided with the idling area (play) 3a can be realized by combining the existing one-way clutch 10 and the electromagnetic clutch 11.

As described above, according to this embodiment, the following effects are achieved.

1) A first folding roller pair 2 (a second transport roller R3 and a third transport roller pair 4 pair: a first transport member pair) that folds a sheet P, and the first folding roller pair 2 that is folded by the first folding roller pair 2. The forward/reverse rotation roller pair 3 (second transportation roller pair R6: second transportation member pair) that transports the sheet P downstream, and the first folding roller pair 2 (first transportation member pair) folded by the above A second folding roller pair 4 (a second transport roller R3 and a fourth transport roller R5 pair: a third transport member pair) that further folds the paper P. Since it is rotatable, locked in one rotation direction when not driven, and rotatable in the other rotation direction, the basic performances (a) to (c) can be exhibited. This makes it possible to prevent box folding during the second paper folding process when folding is performed by the sandwiched reversal method.

2) A first conveyance roller pair R1 (fourth conveyance member pair) that conveys the sheet P, a first conveyance roller R2 that receives the sheet P that is conveyed by the first conveyance roller pair R1, and conveys the sheet P to the subsequent stage and a first conveyance roller R2. In the state in which the paper P is held by the pair of two transport rollers R3 (fifth transport member pair), the pair of first transport rollers R1, the pair of first transport rollers R2 and the second transport roller R3, the first transport is performed. Since the roller R2 and the second transport roller R3 pair are rotated in the opposite directions, the portion corresponding to the fold of the sheet P can be reliably guided to the nip of the first folding roller pair 2.

3) Since the rotatable range is set in advance, it is possible to surely perform the next reverse transport operation after idling.

4) In the preset rotatable range, the forward/reverse rotation roller pair 3 (the second conveying member pair) is stopped, and the second folding roller pair 4 (the third conveying member pair) is the paper sheet. Deflection Pt2 of the sheet P caused between the forward/reverse rotation roller pair 3 (second conveying member pair) and the second folding roller pair 4 (third conveying member pair) when P is conveyed downstream. Since it is a rotation range that is sufficient to eliminate the problem, it is possible to guarantee idling as much as to eliminate the bending that occurs during the second folding process, and to reliably prevent the box folding phenomenon that occurs during the second folding process. It can be avoided.

5) When the sheet P is folded by the second folding roller pair 4 (third conveying member pair), the forward/reverse rotation roller pair 3 (second conveying member pair) is in a stopped state, so The sheet P can be reliably pulled in by the nip of the pair of 2-fold rollers 4.

6) The paper P is transported by the second folding roller pair 4 (third transport member pair), and the forward/reverse rotation roller pair 3 (second transport member pair) pulls on the paper P in association with this transport. The pair of forward/reverse rotation rollers 3 is driven after a preset time before the idle rotation is ended and the idle rotation is ended, so that the second folding roller pair 4 bends the sheet P while bending. The sheet P can be pulled out from the forward/reverse rotation roller pair 3 without load in the absence of the load.

7) The conveyance speed of the paper P when the forward/reverse rotation roller pair 3 (second conveyance member pair) is rotationally driven is the same as that of the second folding roller pair 4 (third conveyance member pair). Since the sheet P is set at a speed equal to or higher than the conveyance speed, the sheet P is not pulled between the forward/reverse rotation roller pair 3 and the second folding roller pair 4. This prevents the paper P from being damaged due to pulling.

8) The forward/reverse roller pair 3 (second conveying member pair) includes a drive member 3a4 that rotates concentrically with the drive shaft 3a2, a driven portion 3a3 driven by the drive member 3a4, and the drive member 3a4. Since the driving unit main body 3a1 (driving unit) including the idling region 3a that idles is provided, the functions (b) and (c) can be reliably exhibited.

9) Since the forward/reverse rotation roller pair 3 (second conveying member pair) is configured as a driving roller, respectively, there is no risk of losing the paper P by the strainer, and the function of the above (b) can be reliably exhibited. it can.

10) Each of the forward/reverse rotation roller pair 3 (second conveying member pair) is a drive roller, and the one-way clutch 10 is provided at the drive portion of one drive roller of the forward/reverse rotation roller pair 3 and the drive of the other drive roller. Since the electromagnetic clutch 11 is provided in the section, the functions (a) to (c), which are the basic functions of the forward/reverse rotation roller pair 3, can be reliably obtained.

11) The image forming system 1 includes the folding processing apparatus 100 (sheet processing apparatus) having any one of the configurations 1) to 10) and the image forming apparatus 200. It is possible to provide a system that achieves the above effect.

In the description of the effects of the above-described embodiment, the components of the present embodiment are shown in parentheses or the reference numerals are attached to the components of the present embodiment to clarify the corresponding relationship between them.

Furthermore, the present invention is not limited to the above-described embodiments, and various modifications can be made without departing from the gist of the present invention, and all the technical matters included in the technical idea described in the claims are included. It is the subject of the present invention. Although the above-mentioned embodiments show suitable examples, those skilled in the art can implement various alternatives, modifications, variations or improvements from the contents disclosed in the present specification, These are included in the technical scope described in the appended claims.

1 image forming system 2 first folding roller pair (first conveying member pair)
3 Forward/reverse roller pair (second conveying member pair)
3a idling area 3a1 drive unit main body 3a2 drive shaft 3a3 driven part 3a4 drive member 4 second folding roller pair (third conveying member pair)
10 One-Way Clutch 11 Electromagnetic Clutch 100 Folding Device 200 Image Forming Device P Paper Pt2 Deflection R1 First Transport Roller Pair (Fourth Transport Member Pair)
R2 first transport roller R3 second transport roller R4 third transport roller R5 fourth transport roller R6 second transport roller pair

JP, 2006-117383, A JP, 2007-277006, A

The present invention relates to a sheet processing apparatus and an image forming system, and particularly to a sheet-shaped recording medium (hereinafter referred to as “sheet”) such as a sheet, a transfer sheet, a printing sheet, and an OHP sheet that has been carried in. The present invention relates to a sheet processing apparatus that performs a folding process, and an image forming system including the sheet processing apparatus and an image forming apparatus such as a copying machine, a printer, a facsimile, and a digital multi-function peripheral.

In order to solve the above problems, the present invention relates to a sheet processing apparatus, and a first conveying member pair that folds a sheet and a second conveying member that conveys the sheet folded by the first conveying member pair to a downstream side. A pair, a third pair of conveying members that further folds a portion of the sheet that is folded by the first pair of conveying members, between the first pair of conveying members and the second pair of conveying members, and the second pair. A driving source for driving the pair of conveying members, the second conveying member pair has a driving roller, and a plurality of driving transmission paths for transmitting the driving force of the driving source to the driving roller are provided. Drive transmission member is provided, and at least one of the plurality of drive transmission members is a drive transmission member having an idle region . The problems, configurations, and effects other than the above will be clarified in the following description of the embodiments.

Claims (11)

A first pair of conveying members for folding the sheet,
A second conveying member pair that conveys the sheet folded by the first conveying member pair to the downstream side;
A third conveying member pair that further folds the sheet folded by the first conveying member pair,
The sheet processing apparatus is configured such that the second pair of conveying members can rotate in forward and reverse directions when being conveyed, and can be locked in one rotation direction and can rotate in the other rotation direction when not being driven. The sheet processing apparatus according to claim 1,
A fourth pair of conveying members for conveying the sheet,
And a fifth transport member pair that receives the sheet transported by the fourth transport member pair and transports the sheet to the subsequent stage,
A sheet processing apparatus, wherein the fifth conveyance member pair is rotated in a reverse direction while the sheet is held by the fourth conveyance member pair and the fifth conveyance member pair. The sheet processing apparatus according to claim 1 or 2,
The sheet processing apparatus, wherein the rotatable range is set in advance. The sheet processing apparatus according to claim 3,
The preset rotatable range is such that the second transport member pair stops and the third transport member pair and the third transport member pair transport the sheet downstream when the second transport member pair is stopped. 2. The sheet processing apparatus, wherein the rotation range is sufficient to eliminate the bending of the sheet generated between the pair of conveying members. The sheet processing apparatus according to claim 4,
The sheet processing apparatus, wherein when the sheet is folded by the third pair of conveying members, the second pair of conveying members is in a stopped state. The sheet processing apparatus according to claim 5,
The sheet is conveyed by the third pair of conveying members, the second pair of conveying members is pulled by the sheet with the conveyance, starts idling, and is set for a preset time before the idling ends. After the lapse of, the second pair of conveying members are rotationally driven in the pulled direction. The sheet processing apparatus according to claim 6,
The conveyance speed of the sheet when the second pair of conveyance members is rotationally driven is set to be equal to or higher than the conveyance speed of the sheet of the third conveyance member pair. Paper processing device. The sheet processing apparatus according to any one of claims 1 to 7,
The second pair of conveying members includes a drive unit that includes a drive member that rotates concentrically with the drive shaft, a driven unit that is driven by the drive member, and an idle region in which the drive member idles. A paper processing device characterized by the above. The sheet processing apparatus according to any one of claims 1 to 8,
The sheet processing apparatus, wherein each of the second pair of conveying members is a driving roller. The sheet processing apparatus according to any one of claims 1 to 8,
The second pair of conveying members are drive rollers,
A one-way clutch is provided in a drive unit of one drive roller of the second conveying member pair, and an electromagnetic clutch is provided in a drive unit of the other drive roller. An image forming system comprising the sheet processing apparatus according to any one of claims 1 to 10.