JP4478595B2 - Paper punching device, paper post-processing device, and image forming apparatus having the same - Google Patents

Description

  The present invention relates to a sheet punching apparatus in a sheet post-processing apparatus including a sorter or finisher that performs punching, sorting, stacking, and the like of transfer paper discharged from an image forming apparatus, and a sheet post-processing apparatus including the sheet punching apparatus and the same The present invention relates to an image forming apparatus including

2. Description of the Related Art Paper post-processing devices that are disposed on the downstream side of image output devices such as copying machines and printers and that perform processing such as punching and binding on output transfer paper are widely known (see, for example, Patent Documents 1 to 3). .
In order to increase the punching hole accuracy of the irregular size paper by the paper post-processing device, it is generally necessary for the user to specify the paper size in the image forming apparatus and to notify the punching device of the size information. Therefore, it is necessary for the user to bother measuring the horizontal and vertical lengths of the size and inputting the values to the image forming apparatus.
In order to save such trouble, in Patent Document 1 or Patent Document 2 and the like, the size is generally measured when paper is fed in the image forming apparatus. However, since the length in the direction perpendicular to the paper transport direction is measured by the width of the jogger fence at the time of paper feeding, generally a value larger than the paper size is measured, and an accurate value cannot be measured. .
Further, in Patent Document 3, in the case of a standard size, the paper center is calculated from known information, the lateral deviation is detected by the paper edge detection sensor, the lateral deviation is eliminated, and the center of the paper is punched. In the case of the irregular size, the center of the sheet is calculated by detecting both ends of the sheet width, the lateral shift is detected by the sheet end detection sensor, the lateral shift is eliminated, and the center of the sheet is punched. That is, Patent Document 3 focuses on perforating around the center position of the paper.
JP 2003-146532 A JP-A-11-217152 JP 2003-128337 A

However, in the configuration of Patent Document 3, it takes time to detect the size in the case of an irregular size. In Patent Document 3, two edge detection means are prepared and the width is measured from both sides of the paper. However, the detection means and the movement means of the detection means are required, and the electromechanical configuration becomes complicated. It was.
In view of the above, the first object of the present invention is to provide a paper punching device that punches at the same position of each paper, not the center of the paper, and increases the accuracy of the paper punching holes. And a post-processing apparatus including the image forming apparatus.
The second object of the present invention is to improve the accuracy of the punched holes in the paper without requiring paper size information from the image forming apparatus, a plurality of sensors, a motor for moving these sensors, and other drive systems. An object of the present invention is to provide a sheet punching device to be enhanced, a post-processing device having the same, and an image forming apparatus having the same.
Another object of the present invention is to provide a paper punching device that anticipates the occurrence of paper jam, punching position misalignment, etc., and notifies the image forming apparatus of an error, a post-processing device including the same, and an image forming device including the same. It is to provide.

In order to solve the above problems, the invention according to claim 1, in the sheet punching device for drilling is equipped with a paper post-processing apparatus to the center reference conveyance in the sheet, a detecting means for detecting the sheet position, the paper Correction means for correcting lateral displacement of the position, and control means, the correction means has a punching means movable in the width direction of the paper, the control means for the first paper on the center reference controlled so as to pierce the reference position of the transfer, the two subsequent paper by detecting the lateral difference between the first sheet relative to the sheet position of the first sheet by said detection means, said by said difference The punching means is moved, and the punching control is performed so that the positions of the holes on the paper overlap regardless of the positional deviation of the paper itself .
According to a second aspect of the present invention, when the difference between the paper edge detection information of the previous paper and the paper edge detection information of the next paper is larger than a certain amount, an error is notified to the image forming apparatus. The paper punching device according to item 1 is characterized.
According to a third aspect of the present invention, there is provided a paper post-processing apparatus including the paper punching device according to the first or second aspect.
According to a fourth aspect of the present invention, there is provided an image forming apparatus including the paper post-processing apparatus according to the third aspect.

  According to the present invention, the punching position of the first sheet is determined based on the reference position of the center reference transport regardless of the size, and the punching positions of the second and subsequent sheets are determined as the punching positions of the first sheet. Since the lateral misalignment is corrected as a reference and punched at the same position as the punching position of the first sheet (a position determined based on the reference position in the center reference transport), a plurality of sensors and a moving mechanism related thereto are required. Therefore, it is possible to improve the accuracy of the punching holes of the paper, and to notify the image forming apparatus of an error in anticipation of a paper jam, punching position deviation, and the like.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 is an overall schematic diagram showing a sheet post-processing apparatus that includes a sheet punching device and can shift sheets. FIG. 2 is a schematic diagram showing a sheet punching device including a lateral registration detection unit A and a punching unit B.
FIG. 1 shows a sheet post-processing apparatus S that includes a punching device (punch unit) 21 for receiving and punching a sheet (not shown) conveyed from the image forming apparatus 20 and can shift the sheet. An overall view is shown. In FIG. 1, a punching device 21 is incorporated in the paper post-processing device S. As shown in FIG. 2, the punching device 21 includes a lateral registration (horizontal registration) detection unit A and a punching unit B.
A general method for punching regular-size paper will be described below, and details of the irregular-size paper will be described later. First, the leading edge of the sheet conveyed from the image forming apparatus 20 is abutted against the stopped skew correction roller pair (entrance roller) 1. After the sheet is abutted for a certain time and the sheet is bent by an appropriate amount, the skew correction roller pair 1 is rotated to resume the sheet conveyance.
The stop time and rotation start timing of the skew correction roller pair 1 are determined by the control unit using the paper leading edge detection performed by the entrance sensor 22 as a trigger, and rotation is started. The sheet whose skew has been corrected by the skew correction roller pair 1 then passes through detection means (here, a lateral registration detection unit A described later) for detecting position information of one side end parallel to the sheet conveyance direction.
The sheet passes through a conveyance path having a sheet post-processing means (in the embodiment, a punch unit as a sheet punching device) for performing post-processing on one sheet of paper, and a conveyance path that leads to the upper tray 23 upon request, a shift tray The branching claw 15 and the branching claw 16 distribute the sheet to the conveyance path leading to 24 and the conveyance path leading to the processing tray that performs alignment, stapling, and the like.
For example, sheets that have been aligned and stapled are configured to be distributed to a conveyance path that leads to the shift tray 24, a processing tray that performs folding, and the like by a branch guide plate 25 and a movable guide 26 that are deflection means. The sheet that is folded in the tray is guided to the lower tray 30 through the folding rollers 27 and 28 and the lower paper discharge roller 29.
Further, a branch claw 17 is disposed in the conveyance path D, and is held in a state shown in the figure by a low-load spring (not shown). After the trailing edge of the sheet passes through the conveyance rollers 9, 10 and staples It is configured such that at least the transport roller 9 of the paper discharge rollers 11 is reversely rotated to guide and stay at the rear end to the paper storage unit E, and can be superposed and transported on the next paper.

An inlet sensor 22 that detects a sheet received from the image forming apparatus 20 is provided in a common introduction conveyance path directly connected to a paper discharge port on the image forming apparatus 20 side, and an inlet roller 1, a punching device 21, and a conveyance roller 2 downstream thereof. The branch claw 15 and the branch claw 16 are sequentially arranged.
The branch claw 15 and the branch claw 16 are held in the state shown in FIG. 1 by a spring (not shown). By turning on a solenoid (not shown), the branch claw 15 is turned upward and the branch claw 16 is turned downward. By doing so, the paper is distributed to the transport roller 3, the transport roller 5, and the transport roller 7.
The paper stacking device included in the paper post-processing device according to the present invention includes a shift paper discharge roller 6, a return roller 13, a paper surface detection sensor 31, a shift tray 24, and the like. The sheets guided to the processing tray by the staple discharge roller 11 are sequentially stacked.
In this case, alignment in the vertical direction (paper conveyance direction) is performed with the tapping roller 12 for each sheet, and alignment in the horizontal direction (paper width direction orthogonal to the sheet conveyance direction) is performed with the jogger fence 32. The sheet bundle subjected to the binding process is immediately sent to the shift discharge roller 6 by the discharge belt 33 having the discharge claw 33a, and is discharged to the shift tray 24 set at the receiving position.
The discharge claw 33a is configured so that its home position is detected by a discharge belt HP (home position) sensor 34. The discharge belt HP sensor 34 is turned on / off by a discharge claw 33a provided on the discharge belt 33. .
The end surface binding stapler S1 is driven via a timing belt by a stapler moving motor (not shown) capable of rotating in the forward and reverse directions, and moves in the paper width direction in order to bind a predetermined position of the paper edge. The saddle stitching stapler S2 is arranged such that the distance from the rear end fence 35 to the staple position of the saddle stitching stapler S2 is equal to or longer than the distance corresponding to half the length in the conveyance direction of the maximum sheet size that can be saddle stitched. .

In the branch guide plate 25 and the movable guide 26 as the sheet bundle deflecting means, the branch guide plate 25 is provided so as to be rotatable in the vertical direction around a fulcrum, and has a pressure roller 36 that is rotatable on the downstream side thereof. ing. The branch guide plate 25 is pressed against the discharge roller 37 by a spring (not shown).
The transport roller 3 and the upper paper discharge roller 4 guide the discharge to the upper tray 23. The state of paper discharge is monitored by an upper paper discharge sensor 39 that is disposed in the vicinity of the upper paper discharge roller 4 and detects paper discharge. Further, the state of paper discharge is monitored by a shift paper discharge sensor 40 which is disposed in the vicinity of the shift paper discharge roller 6 and detects paper discharge.
The operation in sort and stack modes will be described below. The same sheet is conveyed and discharged as in the non-staple mode. At that time, the shift tray 24 swings in the direction orthogonal to the paper discharge direction every time the section is divided, and the discharged paper is sorted.
The operation in the staple mode will be described below. The paper sorted by the branch claw 15 and the branch claw 16 from the conveyance path is guided to the conveyance path D, and is discharged to the processing tray by the conveyance roller 7, the conveyance roller 9, the conveyance roller 10, and the staple discharge roller 11. In the processing tray, the sheets sequentially discharged by the staple discharge roller 11 are aligned, and when the predetermined number of sheets is reached, the end surface binding stapler S1 performs the binding process.
Thereafter, the bound sheet bundle is conveyed downstream by the discharge claw 33 a and discharged to the shift tray 24 by the shift discharge roller 6. The state of paper discharge is monitored by a shift paper discharge sensor 40 that is disposed in the vicinity of the shift paper discharge roller 6 and detects paper discharge. When the staple discharge sensor 41 is passed, the jogger fence 32 moves inward by 5 mm from the standby position and stops.
Then, after a predetermined pulse from the detection by the paper presence sensor 42 or the discharge belt HP sensor 34, the jogger fence 32 is retracted by 2 mm, and the restriction on the paper by the jogger fence 32 is released. This predetermined pulse is set between the time when the discharge claw 33a comes into contact with the rear end of the sheet and then passes through the tip of the jogger fence 32.

The operation in the saddle stitch binding mode will be described below. The paper sorted by the branch claw 15 and the branch claw 16 from the conveyance path is guided to the conveyance path D, and is discharged to the processing tray by the conveyance roller 7, the conveyance roller 9, the conveyance roller 10, and the staple discharge roller 11.
The sheet bundle is conveyed by the upper bundle conveyance roller 43 and the lower bundle conveyance roller 44 to the movable rear end fence 45 which has been moved from the home position to a position corresponding to the sheet size in advance and stopped to guide the lower end surface. The
The sheet bundle abutted against the movable rear end fence 45 is released from the pressurization of the lower bundle conveying roller 44. After that, the vicinity of the stitched needle part is pushed by the folding plate 38 in a substantially right angle direction and guided to the nip of the opposing folding rollers 27 and 28. The folding roller 27 that has been rotated in advance presses and conveys the sheet bundle, thereby folding the sheet bundle at the center.
The folded sheet bundle is strengthened by the second folding roller 28 and discharged to the lower tray 30 by the lower paper discharge roller 29. At this time, when the trailing edge of the sheet bundle is detected by the folding portion passage sensor 46, the folding plate 38 and the movable trailing edge fence 45 are returned to the home position, and the pressurization of the lower bundle conveying roller 44 is restored, and the next sheet is detected. Prepare for. If the next job has the same paper size and the same number of sheets, the movable rear end fence 45 may stand by at that position.
FIG. 1 further shows a punch waste hopper 47, a pre-stack sensor 48, a bundle arrival sensor 49, a movable rear end fence HP sensor 50, a lower bundle conveyance guide 51, and an upper bundle conveyance guide 52.

FIG. 3 is a schematic diagram showing the internal configuration of the lateral registration detection unit A of the paper punching device of FIG. 2 as viewed from the right side. FIG. 4 is a schematic diagram for explaining the relationship between the actual sheet passing position and the ideal sheet passing position. FIG. 5 is a schematic diagram showing a punching unit B of the paper punching device of FIG.
In the present invention, the position of the edge in the width direction of the irregular sheet conveyed by the lateral registration detection unit A is detected, and the punching unit B is moved based on the amount of deviation in the width direction determined based on the detection result. In this way, perforations are made at appropriate positions on the paper.
Here, the edge position detection sensor 61 of the lateral registration detection unit A (first moving means) is formed using the sheet size data from the image forming apparatus 20 together with the off signal (sheet trailing edge detection) of the entrance sensor 22. The width direction movement start timing is calculated.
When the movement start timing determined based on the paper detection of the entrance sensor 22 is reached, the lateral registration detection unit A starts to move in the width direction, and the end position detection sensor 61 (FIG. 3) formed of a photo interrupter or the like is used for the paper. Detect location information. Thereafter, the sheet passes through a punching means (perforation unit B) that can move in width and punches the conveyed paper.
In the case of the punching mode, the punching hole position is calculated from the position information on the paper side edge, and the punching unit B (second moving means) is moved to the hole position to punch. Thereafter, the paper is sorted by a paper moving means that can move the paper in a direction (width direction) orthogonal to the transport direction, and is discharged to the paper discharge tray 24. Details of correction at the time of drilling will be described below.
An edge position detection sensor 61 (horizontal registration detection sensor) that detects an edge position parallel to the conveyance direction of the sheet conveyed to the lateral registration detection unit A (detailed view is shown in FIG. 3) is orthogonal to the conveyance direction. It is configured to move forward and backward in the width direction (arrow direction in FIG. 3).

In FIG. 3, the end position detection sensor 61 is attached to a paper guide 71, and the paper guide 71 is attached to a holder 74. The holder 74 moves back and forth in the width direction while sliding on the shaft 73.
A timing belt 78 is engaged with the holder 74, and the timing belt 78 is operated by rotation of the stepping motor 76 with the timing belt 78 placed between the output pulley 76 and the pulley 80 of the stepping motor. As a result, the holder 74, the paper guide 71, and the end position detection sensor 61 move in the width direction.
The home position (standby position) of the end position detection sensor 61 is determined by detecting a part 74a of the shape of the holder 74 by a sensor 75 (fixedly arranged) made of a photo interrupter or the like. From the standby position (75 in FIG. 4) where the sensor 75 detects the holder 74, the end position detection sensor 61 slides on the shaft 73 through a series of components by driving the stepping motor 76, and the paper transport direction. Is moved in the width direction (left side in FIG. 3) in order to detect the end parallel to the line.
Here, a is the amount of movement of the end position detection sensor 61 per pulse of the stepping motor 76. At that time, for example, when the sheet has been transported to an ideal position with no lateral registration deviation, an end position detection sensor until the end (width direction end) parallel to the sheet transport direction is detected. The amount of movement w from the standby position 61 is 10a. This movement amount w is stored in the storage unit as a reference value.

Actually, when the amount of movement of the edge position detection sensor 61 until the edge parallel to the conveyance direction of the conveyed paper is detected becomes 11a, the lateral registration deviation Δd of a distance of 11a−10a = 1a. Will occur. (See Figure 4)
By operating the punching unit B in the width direction so as to correct the shift amount Δd corresponding to 1a, it is possible to always set the punched hole of the paper at a fixed position. This perforation unit B will be described. (See Figure 5)
The moving drive source of the drilling unit B is a stepping motor 69, from which it is transmitted to the gear / pulley 82 via the timing belt 70 and rotated. The gear of the gear / pulley 82 meshes with a rack 66 extending in the width direction. As the gear / pulley 82 rotates, the rack 66 moves in the width direction indicated by the arrow in FIG.
The rack 66 is mounted on the lower punch guide plate 68, and the punching unit B (punch blade 62, punch upper guide 67, shaft 63, cam 84, punch blade holder 83, clutch 64, motor 65) is all provided in the lower punch guide. The plate 68 is assembled. Therefore, as the rack 66 moves, the punching unit B moves forward and backward in the width direction as a whole.
Here, the moving amount of the punching unit B per pulse of the stepping motor 69 is assumed to be b. As described above, if the relationship between the movement amount a of the end position detection sensor 61 of one pulse of the stepping motor 76 of the lateral registration detection unit A and the movement amount b approximates to an integral multiple (for example, double), a = 2 × b (relational expression of movement amount).
As described above, when the lateral registration of the sheet is shifted by 1a, the movement distance of one pulse of the edge position detection sensor 61 is a, which means that one pulse of lateral registration is shifted. Therefore, the punching unit B needs to input a pulse for moving the distance of 1a to the stepping motor 69.
Since the relationship of the movement distance of one pulse is a = 2 × b, the number of pulses input to the stepping motor 69 is twice the number of pulses corresponding to the deviation amount calculated from the end position detection sensor 61.
That is, the edge position information from the edge position detection sensor 61 is recognized as a pulse, and the CPU (control unit) compares it with the sheet width size information to calculate the lateral registration deviation amount of the sheet. The calculation result is input to the stepping motor 69 as a pulse to move the drilling unit B.
At this time, the number of pulses input to the stepping motor 69 is obtained from a = 2 × b (movement amount relational expression), so that the error of moving with the pulse is reduced and the hole position accuracy is improved. Also, the number of pulses input to the stepping motor 69 that always moves the drilling unit B regardless of the amount of deviation is expressed by a = 2 × b (movement amount relational expression), so software control can be easily performed. .

According to the first embodiment of the present invention, the first irregular-size sheet conveyed from the image forming apparatus 20 is first skew-corrected by the skew correction roller pair 1 as described above. Thereafter, the lateral registration detection unit A is moved in order to detect the position of the end in the width direction of the paper.
However, since the sheet size information is not obtained in advance, the movement timing is calculated here assuming the minimum value of the sheet passing size. In this case, the conveyance center is not the sheet conveyance center, but the position of the conveyance center of the machine determined by the model for discharging from the image forming apparatus 20 (FIG. 1) to the post-processing apparatus S (FIG. 1) is set as a default value. Use.
The trigger for detection is an off signal (sheet trailing edge detection) of the entrance sensor 22. Here, since the punching position is the trailing edge of the paper, the trigger is the paper trailing edge detection. However, if the punching position is the leading edge of the paper, the leading edge of the paper is detected.
The paper edge position information measured by the lateral registration detection unit A is stored as DAT1. The transported first sheet is punched by moving the punching unit B to the transport center (the movement distance is Dcenter).
Similarly to the first sheet, the second sheet conveyed next measures sheet edge position information (referred to as DAT2) by the lateral registration detection unit A. Here, DAT1 and DAT2 are compared, and a difference in lateral registration deviation Δd (DAT1-DAT2) is calculated.
Thereafter, the punching unit B is moved in the width direction by Dcenter + Δd to perform punching, so that the positional deviation of the punching holes does not occur in the first and second sheets. Similarly, for the subsequent sheets (Xth sheet), a deviation amount Δd between the first DAT1 and the measured DATX is obtained, and if the perforation unit B moves the correction amount, the first and Xth sheets are displaced. Does not occur.

In the second embodiment, when the lateral registration deviation Δd is larger than a certain fixed amount _Dmax , there is a possibility that a paper jam, a punching position deviation, or the like may occur, so that an error is notified to the image forming apparatus. (Error handling). Here, the fixed amount D _max uses a movable range of the punching unit B or a sheet acceptance standard value of the image forming apparatus.
FIG. 6 is a flowchart showing the operation of the first and second embodiments. Control of each unit is performed by a control unit (not shown).
In FIG. 6, first, it is determined whether or not the entrance sensor 22 has detected the leading edge of the sheet (S1). Next, it is determined whether or not the trailing edge of the sheet has passed the entrance sensor 22 (S2). If it has passed, the timer is cleared (S3).
It is determined whether or not the timer has reached a certain time (S4). If the fixed time has elapsed, the movement of the lateral registration detection unit A (FIG. 3) is started (S5). Next, it is determined whether or not the lateral registration detection unit A has left the home position 75 (FIG. 4) (S6). If the home position 75 is passed, it is determined whether or not the lateral registration detection sensor 61 has detected the end face of the paper (S7).
If the end face of the paper is not detected, the moving distance measurement counter is incremented every pulse (S8). If the end face of the sheet is detected in step (S7), DATX is acquired (S9), and the lateral registration detection unit A is stopped (S10). Next, it is determined whether or not the sheet is the first sheet (S11).
If the sheet is the first sheet, movement of the punching unit B to the transport center is started (S12). If it is not the first one in step (S11), Δd = DAT1-DATX is calculated (S15), and then it is determined whether | Δd |> _Dmax (S16). If | Δd |> D _max , an error is notified to the image forming apparatus (S18).
If | Δd |> D _max does not exist, movement of the drilling unit B by D _max + Δd is started (S17). Next, it is determined whether or not the punching unit B has stopped and the sheet has stopped at the punching position (S13). If stopped at the drilling position, drilling is performed at that position (S14).

  As described above, the present invention mainly focuses on punching at the same position of each sheet, not at the center in the width direction of the sheet. In other words, the punching position for the first sheet is the transport center, which is the reference position in the center reference transport apparatus, regardless of the sheet size (regardless of the regular or irregular shape), and the punching position for the second and subsequent sheets is After correcting the lateral misalignment on the basis of the position of the first sheet, punching is performed at the same position as the punching position of the first sheet. As a result, it is possible to increase the speed by punching without detecting the size of the irregular shaped paper. In this case, the first sheet may be laterally displaced from the center reference position, but in this case, the first sheet is not punched at the center of the sheet. However, since the next sheet is controlled to be punched at the same position as the first sheet, the punching position does not differ between the sheets.

1 is an overall schematic diagram illustrating a sheet post-processing apparatus that includes a sheet punching device and can shift a sheet. FIG. 3 is a schematic view showing a perforation apparatus including a lateral registration detection unit A and a perforation unit B. FIG. 3 is a schematic diagram illustrating a lateral registration detection unit A of the paper punching device of FIG. 2. It is the schematic explaining the relationship between an actual paper passing position and an ideal paper passing position. FIG. 3 is a schematic diagram showing a punching unit B of the paper punching device of FIG. 2. It is a flowchart which shows operation | movement of 1st and 2nd embodiment.

Explanation of symbols

1 Paper transport means (entrance roller)
20 Image forming apparatus 21 Paper punching device (punch unit)
22 Paper detection means 61 Edge detection means (edge position detection sensor, lateral registration detection sensor)
A Side registration detection unit B Side shift correction means (perforation unit)
S Paper post-processing device

Claims (4)

In a paper punching device that is equipped in a post-processing device that transports paper in a center reference and punches paper,
Detection means for detecting the paper position;
Correction means for correcting lateral displacement of the paper position;
Control means,
The correction means has a punching means movable in the width direction of the paper,
The control means 1 as the first sheet of the sheet is controlled so as to pierce the reference position of the center reference conveyance, the two subsequent sheet based on the paper position of the first sheet by said detecting means The sheet punching is characterized by detecting a difference in lateral deviation from the sheet, moving the punching means by the difference, and controlling punching so that the positions of the holes on the sheet overlap regardless of the positional deviation of the sheet itself. apparatus.   2. The control unit according to claim 1, wherein when the difference between the sheet edge detection information of the preceding sheet and the sheet edge detection information of the next sheet is larger than a certain amount, the control unit processes the error. Paper punching device.   A paper post-processing apparatus comprising the paper punching device according to claim 1.   An image forming apparatus comprising the sheet post-processing apparatus according to claim 3.

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