JP4695380B2 - Paper processing apparatus and image forming apparatus - Google Patents

Description

  The present invention is provided with an image forming apparatus and the like, and a sheet processing apparatus for sorting, binding, stacking, and the like of a sheet-like transfer medium discharged from the apparatus, for example, transfer paper (paper), and the sheet processing apparatus are integrated or separated. The present invention relates to an image forming apparatus provided on a body.

  As this type of technology, for example, the technology disclosed in Patent Document 1 is known. In this document, the branching claw 17 is arranged in the conveyance path D, and after the trailing edge of the paper passes through this, the conveyance roller is reversed so that the trailing edge of the paper is guided to the paper accommodating portion and the paper is retained. A paper processing apparatus configured to be able to overlap and transport paper is described. In this paper processing apparatus, it is also possible to transport two or more papers in a superimposed manner by repeating the above operation. It has become.

  Patent Document 2 discloses a conveying unit that conveys a sheet to a discharge port along a conveying path, a staying unit that temporarily retains the sheet on the conveying unit, and a sheet that is conveyed by the conveying unit. Sheet processing having determination means for determining whether or not the paper is special paper, and, when the sheet conveyed by the conveyance means is special paper, a staying number limiting means for limiting the number of sheets retained by the staying means An apparatus is described.

Further, Patent Document 3 discloses a paper discharge tray for directly stacking paper discharged from the image forming apparatus or stacking a post-processed paper bundle, a post-processing tray for post-processing the paper bundle, In the sheet post-processing apparatus including a first transport path from the entrance portion toward the paper discharge tray and a second transport path branched from the first transport path and toward the post-processing tray, A sheet post-processing apparatus, wherein a switching claw is provided on the conveyance path, and a staying conveyance path branched from the first conveyance path by the switching claw and joined to the second conveyance path is provided. Is described.
JP 2004-001998 A JP 2001-097631 A JP-A-11-199128

  By the way, in the paper processing apparatus described in Patent Document 1, when a paper is transported to a curved paper storage unit, it is transported by a single roller. Therefore, there is a possibility of slipping due to the strength of the waist when transporting cardboard.

  When a sheet, for example, a cover sheet is conveyed from an inserter that feeds a cover sheet or slip sheet, the information on the paper size is clearly known, but the information on the paper type is not clear. There is a possibility of slipping for a reason. The paper conveyed from the inserter is not limited to cardboard, but if the cardboard is transported and slips, the image surface may become dirty.

  The present invention has been made in view of the above points, and a first object of the invention is to prevent image smearing due to slipping in cardboard.

  Further, when a sheet is conveyed from the inserter, it is necessary to leave an interval between jobs in order to prevent contact between the sheet from the inserter and the sheet conveyed from the image forming apparatus. Therefore, there is a margin in the alignment time on the processing tray. On the other hand, if the amount of misalignment between the paper on the other transport path and the next paper is large, when the paper is discharged onto the processing tray, the leading edge of the paper passes through the discharge claw that is an alignment means. If the sheet passes, the alignment accuracy in the sheet conveyance direction is deteriorated, and in the worst case, binding is lost.

  The present invention has been made in view of such a point, and a second object of the invention is to prevent stitch-out and misalignment even when the interval between jobs becomes large.

In order to achieve the above object, according to the first aspect of the present invention, there is provided a first conveying path for guiding the sheet to the processing tray, and a second branching from the first conveying path to temporarily retract the sheet. A transport path, transport means for transporting the paper in the direction opposite to the processing tray side or the processing tray side, and the second transport of the paper when the paper is caused to flow backward by the transport means Switching means for guiding to the path, and a paper processing apparatus having a function of superimposing and transporting the preceding paper temporarily retracted to the second transport path on the following paper Is arranged closer to the processing tray than the switching means, and holds the preceding paper when the preceding paper is temporarily retracted to the second transport path, and If the paper is thick , The trailing edge of the sheet to the preceding present in the first transport path is a local portion definitive in the second transport path, the position along the approximately half of the rotation guide surfaces interlocked with the conveying means It is arranged, before reaching the curved portion formed by being separated by a dimension greater than the thickness of the paper with respect to and the rotating guide, and further comprising a means for stopping the reverse flow of the paper to the preceding To do.

According to a second aspect of the present invention , in the first aspect of the present invention , there is provided a means for changing a transport distance to flow backward to the second transport path.

According to a third aspect of the present invention , in the second aspect of the present invention , the transport distance for backflow is constant regardless of the size of the paper.

Invention of claim 4, in the invention of the invention or claim 3, wherein according to claim 2, wherein said sheet staying in the second conveying path is, n (n is a natural number) th the preceding paper which is characterized in that it is discharged to the processing tray ahead of the paper to the rear row of the (n + 1) th.

According to a fifth aspect of the present invention, the sheet processing apparatus according to any of the first to fourth aspects of the present invention is characterized in that the image forming apparatus is provided integrally or separately .

  In the embodiment described later, the processing tray is the staple tray 14, the first transport path is the lower transport path 2c, the second transport path is the pre-stack path 2d, and the transport means are transport rollers 5, 7 and In the rotation guide 6, the switching means is the switching claw 9, the stopping means and the means for changing the transport distance are in the CPU 360, the discharging means is the discharging belt 13 and the discharging claws 13a and 13b, the image forming apparatus is indicated by reference numeral 1, The processing devices correspond to reference numeral 2, respectively.

  According to the present invention, when the sheet is thick, the sheet is stopped in front of the curved portion of the second conveyance path, so that it is possible to prevent the image from being stained due to slip.

  In addition, since the standby position of the discharge claw is set above the leading edge of the paper, it is possible to prevent binding miss and misalignment.

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

  FIG. 1 is a diagram showing a system configuration of a sheet processing system that uses a sheet post-processing apparatus as a sheet processing apparatus according to an embodiment of the present invention in connection with an image forming apparatus. In FIG. 1, the sheet post-processing apparatus 2 is connected to the image forming apparatus 1, and an inserter 15 is disposed therebetween. The paper discharge port 1a of the image forming apparatus 1, the paper feed port 15a of the inserter 15 and the carry-in port 2a of the paper post-processing device 2 are arranged in a straight line, and the paper from the image forming device 1 passes through the paper feed port 15a of the inserter 15. Through the inlet 2a of the sheet post-processing apparatus 2.

  The sheet post-processing apparatus 2 includes an entrance conveyance path 2b, a lower conveyance path 2c, a prestack path 2d, conveyance rollers 5 and 7, a rotation guide 6, a tray discharge roller 8, a discharge belt 13, a staple tray 14, and an alignment fence 10. The rear end fence 11, the end face binding stapler 12, the discharge roller 21, the movable guide 22, the branch guide plate 23, the paper discharge roller 24, and the paper discharge tray 3 are mainly configured. The inserter 15 includes a cover 20 or a slip sheet mounting table 20, a pickup roller 16, a transport path 15b, and transport rollers 17, 18, and 19.

  The shift transport path 2b guides the paper or cover sheet (interleaf) carried into the carry-in entrance 2a as it is or shifts to the paper discharge tray 3, and the lower transport path 2c guides the paper to the staple tray 14. The paper is branched in the middle of the shift conveyance path 2b, and the paper branching direction is controlled by the branching claw 2e at the branching point. The lower transport path 2c is provided with a pre-stack path 2d. The pre-stack path 2d transports the paper in the reverse direction by reversing the rotation guide 6 and the transport roller 7, and temporarily stores the paper.

  The paper output from the image forming apparatus 1 enters the paper post-processing device 2 through the paper discharge port 1a, the paper supply port 15a, and the carry-in port 2a, detects the paper by the inlet sensor SN1, and illustrates the branching claw 2e by the inlet roller 4. By being rotated counterclockwise, it is guided to the lower conveyance path 2c. The sheet guided to the lower conveyance path 2c is rotated by the switching claw 9 in the counterclockwise direction in the figure by the movement force of the sheet, passes through the lower conveyance path 2c secured thereby, and is conveyed to the conveyance roller 7 and the tray. It is conveyed to the staple tray 14 by the roller 8. The conveyed sheet falls by its own weight in the direction of arrow B, and is knocked down by the tapping roller 14a, and the trailing end fence 13 aligns the trailing end in the conveying direction. Then, the trailing edge of the sheet is detected in advance by the sensor SN2, and the width direction is aligned by the alignment fence 10 after a time during which the sheet conveyance direction can be aligned. By repeating this operation, a large number of sheets are aligned one by one.

In the case of 1 part, the operation is as described above, but in the case of 2 parts or more, the operation is as follows.
The interval between sheets output from the image forming apparatus 1 is constant, and the interval between jobs is also constant. When the first copy is output from the image forming apparatus 1, signals such as the paper size, number of sheets, transport speed, and processing mode are sent. When the signal is received by the sheet post-processing device, the number of sheets to be stacked, the acceleration point, the acceleration linear velocity, the backflow point, and the stop point at the time of stacking are determined.

  The actual sheet processing operation is shown in FIGS. The leading sheet of the job output from the image forming apparatus 1 is conveyed by the entrance roller 4 and the conveyance roller 5 of the sheet post-processing apparatus 2, passes through the switching claw 9, and is conveyed to the position shown in FIG. At this time, when it is necessary to reverse the sheet by a signal from the image forming apparatus 1, the transport roller 7 and the rotation guide 6 are stopped once and reversely rotated in the direction of the arrow shown in FIG. Start. At that time, the switching claw 9 is operated, and the sheet is guided to the prestack path 2d and prestacked. The distance conveyed to the prestack path 2d is controlled by a pulse count from the entrance sensor SN1, a timer, or the like, and stops when the front end position is the same for any paper size. At this time, the sheet is stopped in a state where it is caught in the nip of the conveying roller 7.

  Next, as shown in FIG. 2C, the second sheet is conveyed by the conveying roller 5. Then, when the leading edge of the second sheet is conveyed upstream from the conveying roller 7 to a position of a predetermined distance, for example, 10 mm, based on the detection information of the entrance sensor SN1, the second conveying path as shown in FIG. As shown in FIG. 2D, the conveyance rollers 7 and the rotation guide 6 are rotated in the direction of the arrow (counterclockwise in the drawing), and the conveyance of the sheets stacked in 2c is started. Since the first sheet of the job is re-conveyed in a state of being nipped by the nip of the conveyance roller 7, two sheets are discharged onto the staple tray 14 simultaneously with the leading edge of the first sheet of the job preceding the leading edge of the second sheet. The

The discharged sheet bundle is rotated by a discharge belt 13 installed in parallel with the sheet conveyance direction at the center of the staple tray 14, and a pair of discharge claws 13 a and 13 b installed at symmetrical positions of the discharge belt 13. Moves in the direction of arrow B, strikes the leading edge of the paper with the back of one discharge claw (for example, 13a) , drops the paper to the trailing edge fence 11, and aligns the deviation in the transport direction. Thus, post-processing can be performed without reducing the productivity and binding quality of the main body. The discharge belt 13 is stretched between the discharge roller 21 and the driven roller 21a, and performs an alignment operation in the paper discharge operation.

  The above is the conveyance situation in the case of two sheets. When two sheets or three sheets are stacked according to the processing contents in the staple tray 14 and the time between jobs is increased, post-processing can be performed without dropping the CPM of the main body by repeating the above operation.

  In this embodiment, the timing of re-conveying the paper that has been waiting in the prestack path 2d is set at the position 10 mm upstream of the conveyance roller 7 as described above. The position does not need to be 10 mm, and is set as close to the transport roller 7 as possible on the premise that the leading edge of the (N + 1) th sheet does not enter the transport roller 7 during the slow-up of the transport roller 7.

  Further, in the above description, the rotation guide 6 and the transport rollers 7 and 8 are driven in the same way, but the same operation can be performed even in separate driving. It is also possible to configure the guide so that the guide is rotated by its own weight without driving the rotating guide 6, and by these configurations, post-processing can be performed without reducing the productivity of the main body of the image forming apparatus 1. It becomes possible.

The control when the cover is conveyed from the inserter 15 will be described below. The pre-stacking operation of the cover conveyed from the inserter 15 (operation waiting in the pre-stack path 2d) is basically the same as described above. Therefore, the sheet transport operation is as shown in FIGS. As shown in FIG. 5, when the different parts are conveyed backward and are constant regardless of the sheet size and the sheet is thick, the trailing edge of the preceding sheet existing in the lower conveyance path 2c is the prestack path 2d. large a local curved portion F (prestack path 2d of being located at a position along the substantially half of the surface of the rotation guide 6 interlocked with the conveying roller 7, than the thickness of the sheet and with respect to the rotation guide 6 It is a point of stopping before reaching ( denoted a place formed by dimensions ). The subsequent conveying operation to the staple tray 14 is the same as the operation described with reference to FIGS. 2C and 2D as shown in FIGS. When two or three sheets are pre-stacked, since the sheet is conveyed from the main body of the image forming apparatus 1, the same control as the above-described operation is performed.

For alignment with the staple tray, when the sheet is conveyed from the image forming apparatus main body, the amount of misalignment between the sheets at the time of pre-stacking is set to about 15 mm, but when conveying from the inserter,
Length of paper-(distance from conveyance roller 7 to separate conveyance path curved portion F)
Therefore, the amount of deviation changes depending on the paper size.

  Therefore, in the case of two-sheet binding, the sheets conveyed from the inserter 15 and stacked in the second conveyance path 2c are discharged onto the staple tray 14 with the leading edge shifted as shown in FIG. . At this time, the amount of deviation differs depending on the size of the paper as described above. Therefore, the standby position of the discharge claw 13a is changed based on the paper size information and the prestack number information, and waits about 10 mm above the length of the stacked paper in the transport direction (FIG. 8). At this time, the distance between the front end of the paper and the discharge claw 13a is constant regardless of the size of the paper. When the paper is discharged to the staple tray 14, as shown in FIG. 9, the leading edge of the paper is knocked down with the back of the discharge claw 13 a so as to abut against the rear end fence 11, and the conveyance direction is aligned. Then, as shown in FIG. 10, the sheet bundle is pushed up by the discharge claw 13 b and discharged to the discharge tray 3.

  In this way, by setting the standby position of the discharge claw 13 above the leading edge of the paper, when the paper is discharged to the staple tray 14, the discharge claw 13a is prevented from getting over. The sheet can be reliably abutted against the leading edge of the sheet without swinging and can be aligned in the sheet conveying direction.

  As described above, when the inserter 15 is used, it is possible to prevent slippage of cardboard conveyed as a cover sheet from the inserter 15 by changing the pre-stack operation, and the stapling process is performed without reducing productivity. Is possible. That is, when a cover is conveyed from the inserter 15, an interval is formed between the sheet conveyed from the main body of the image forming apparatus 1 and the cover from the inserter 15 to prevent the image forming apparatus 1 from colliding. Compared with the case where the sheet is conveyed only from one main body, there is a margin in the alignment time in the staple tray 14, and as a result, the shift amount can be changed.

  FIG. 11 is a block diagram showing a control device 350 for realizing these controls. The control device 350 includes a microcomputer having a CPU 360, an I / O interface 370, and the like. Signals from the sensors such as the sensor SN1 and the sensor SN2 are input to the CPU 360 via the I / O interface 370. 5 shows the punch unit 100, this punch unit is arranged on the downstream side of the entrance roller 4 in FIG.

  The CPU 360, based on the input signal, the rotation guide 6, the transport rollers 4, 5, 7, the tray discharge roller 8, the discharge motor that drives the discharge roller 21 (discharge belt 13), and the staple movement motor that moves the stapler 12. In addition, the driving of a stapling drive motor that performs a stapling operation, a discharge motor that drives the discharge roller 24, an alignment motor that drives the alignment fence 10, and the like is controlled. The sheet post-processing device 2 is controlled by the CPU 360 executing a program written in a ROM (not shown) while using a RAM (not shown) as a work area. In addition, the program data is downloaded from a server via a network or from a recording medium such as a CD-ROM or SD card to a storage medium such as a hard disk device (not shown) via a recording medium driving device instead of or in addition to the ROM. It can also be used after being rolled or upgraded.

1 is a diagram illustrating a system configuration of a sheet processing system according to an embodiment of the present invention. FIG. 6 is an explanatory diagram illustrating a sheet standby operation and a stacking operation. It is operation | movement explanatory drawing which shows operation | movement when a cover is carried in from an inserter. It is operation | movement explanatory drawing which shows operation | movement when a cover is carried in from an inserter. It is operation | movement explanatory drawing which shows operation | movement when a cover is carried in from an inserter. It is operation | movement explanatory drawing which shows operation | movement when a cover is carried in from an inserter. It is operation | movement explanatory drawing which shows operation | movement when a cover is carried in from an inserter. It is operation | movement explanatory drawing which shows the alignment operation | movement by a discharge claw. It is operation | movement explanatory drawing which shows the alignment operation | movement by a discharge claw. It is operation | movement explanatory drawing which shows the alignment operation | movement by a discharge claw. FIG. 3 is a block diagram illustrating a control configuration of the sheet processing system according to the embodiment of the present invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Image forming apparatus 2 Paper post-processing apparatus 2b Shift conveyance path 2c Lower conveyance path 2d Prestack path 5,7 Conveyance roller 6 Rotating guide 9 Switching claw 13 Release belt 13a, 13b Release claw 14 Stipple tray 360 CPU
F Curved part

Claims (5)

A first conveyance path that guides the sheet to the processing tray, a second conveyance path that branches from the first conveyance path and temporarily retracts the sheet, and the sheet is disposed on the processing tray side or the processing tray. Conveying means for conveying in the direction opposite to the side, and switching means for guiding the sheet to the second conveying path when the sheet is caused to flow backward by the conveying means,
In the paper processing apparatus having a function of superimposing and conveying the preceding paper temporarily retracted to the second conveyance path with the following paper,
The conveying means is disposed closer to the processing tray than the switching means, and holds the preceding sheet when the preceding sheet is temporarily retracted to the second conveying path. Yes,
Further, if the sheet is thick, wherein the preceding trailing edge of the sheet present in the first transport path is a local portion definitive in the second transport path, the surface of the rotation guide interlocked with the conveying means disposed in a position along the approximately half, and before reaching the curved portion formed by being separated by a dimension greater than the thickness of the paper with respect to the rotation guide, stopping the reverse flow of the paper to the preceding A sheet processing apparatus comprising means.   2. The sheet processing apparatus according to claim 1, further comprising means for changing a transport distance to flow back to the second transport path.   The paper processing apparatus according to claim 2, wherein the transport distance for the reverse flow is constant regardless of the size of the paper.   The paper staying in the second transport path is discharged to the processing tray by the preceding paper of n (n is a natural number) preceding the succeeding paper of n + 1. The sheet processing apparatus according to claim 2 or 3,   An image forming apparatus comprising the sheet processing apparatus according to claim 1 as a single unit or as a separate body.

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