JP4698363B2 - Sheet processing apparatus and image forming apparatus - Google Patents

Description

  The present invention relates to a sheet processing apparatus that accepts and punches sheets discharged from an image forming apparatus such as a copying machine, a printer, a facsimile machine, and a multifunction machine, and other office machines, and an image in which this sheet processing apparatus is incorporated / connected. More specifically, the present invention relates to a technique for positioning a punching position in the width direction of a conveyed sheet.

  Sheet processing that accepts sheets transported from image forming apparatuses such as copiers, printers, facsimiles, etc., and performs processing such as punching or alignment, sorting, stacking, staple binding, folding, bookbinding, and inspection including punching The device has been put into practical use. Also, in some models of image forming apparatuses, such a sheet processing apparatus is built in or connected as a purchase option (so-called option).

  The sheet processing apparatus disclosed in Japanese Patent Application Laid-Open No. 2004-228561 is disposed at the subsequent stage of the image forming apparatus, and is provided with a punch unit (perforating means) in the conveyance path of the sheet received from the image forming apparatus. The sheet processing apparatus includes a processing tray for performing stapling (needle binding) processing. The sheets punched by the punching device are continuously discharged and stacked on a sheet stacking member (stacking tray) or punched by a punch unit. Staple processing can be performed by stacking the stacked sheets.

  The punching device disclosed in Patent Document 1 can adjust the punching position of a sheet in the width direction by moving a pair of punching members (punch) in the width direction with respect to the sheet conveyed in the length direction.

  Then, it has a lateral registration detection sensor that moves in the width direction of the sheet and detects an edge in the width direction of the sheet being conveyed, and uses the detection result of the lateral registration detection sensor to detect the width of the pair of punching members. By adjusting the amount of movement in the direction, the sheet and the punching position are centered.

  This eliminates the effects of skew and lateral misalignment of the sheet discharged from the image forming apparatus and matches the punching position of each sheet with high accuracy and performs punching by aligning the sheets one by one in the width direction. Compared to the above, edge detection and punching position adjustment are completed in a short time, enabling high-speed punching processing of sheets, and maintaining high productivity of the image forming apparatus.

Japanese Patent Laid-Open No. 10-194557

  With the recent remarkable increase in speed in image processing apparatuses, there is a case where further speedup is required for sheet punching processing. On the other hand, there is also a demand to adjust the perforation position with high accuracy and cleanly align the edges of the sheet bundle that has been perforated even though the speed of perforation processing is sacrificed to some extent. In addition, the accuracy of the punching position varies if the skew or curl state of the sheet changes depending on the size and material of the sheet used, the state of the formed image, etc. There is also a demand for adjusting the accuracy of the drilling position according to the situation.

  However, in the drilling device disclosed in Patent Document 1, the speed of the drilling process and the accuracy of the drilling position are fixed as shipped, and there is no room for adjustment. In addition, changing the drilling speed and drilling position accuracy requires specification changes at the part level, so the drilling speed and drilling position accuracy are adjusted at the time of shipment according to the situation and convenience of the delivery destination. It is not easy to do.

  The present invention provides a sheet processing apparatus capable of easily switching and setting the balance between the accuracy of the punching position and the productivity without adding new parts or incurring a cost increase due to part change or processing program change, and An object of the present invention is to provide an image forming apparatus.

The sheet processing apparatus of the present invention is arranged to convey a sheet in a predetermined direction along a conveying path, and to be movable in an intersecting direction intersecting the predetermined direction, and perforates the sheet conveyed by the conveying unit and perforating means for perforating process in position, the side edge sensor for movably arranged sheet side edge detection to the the cross direction crossing the predetermined direction, on the inner side of the side edge sensor in the intersecting direction A leading edge / rear edge detecting sensor for detecting a leading edge and a trailing edge of a sheet which is arranged and conveyed by the conveying means; a moving means for moving the side edge detecting sensor and the punching means in the intersecting direction; and the conveying means In the state in which the conveyance unit is stopped, the moving unit is operated and the accuracy detection mode in which the side end detection sensor detects the side edge of the sheet, and the sheet is conveyed by the conveyance unit. A sheet productivity-oriented mode for detecting a side edge of the said side end detecting sensor in it which state is operated the moving means, a setting for switching means switches the,
Is stopped by moving the perforating means to the drilling position by said moving means and said side end detecting sensor after detecting the side edge of the sheet, then, by conveying the sheet into the puncture hole position location by the transport means in the sheet processing apparatus and a control means for executing the punching process by the punching means, the side edge sensor, the intersection that intersects the predetermined direction such that each is selected to correspond to different sheet sizes The plurality of side end detection sensors and the punching means are integrally moved in the intersecting direction, and are selected according to the sheet size. the side edge sensor, the perforation means by further moving the plurality of the side edge sensor and said perforating means after detecting the side edge of the sheet in the punching position Constant, and the control unit, when the precision priority mode is set by said switching means, temporarily stops the conveyance of the sheet by the conveying means in response to the leading edge detection of the sheet by the tip / rear end detecting sensor And moving the punching means and the plurality of side edge detection sensors in the intersecting direction by operating the moving means in a state where the conveyance of the sheet is stopped, and is selected according to the sheet size. After the side edge detection sensor detects the side edge of the sheet, the moving means further moves the remaining distance necessary for setting the punching position to the punching position, stops the sheet , and further conveys the sheet by the conveying means. was resumed, stops the sheet conveyance by the conveying means in response to the trailing edge detection of the sheet by the tip / rear end detecting sensor, then, before the said punching means When the productivity emphasis mode is set by the switching unit, the control unit performs the punching process, and after the sheet leading edge is detected by the leading edge / rear edge detecting sensor, The side edge detection sensor selected according to the sheet size by starting the operation of the moving means when the sheet is conveyed by a predetermined distance, and moving the punching means and the plurality of side edge detection sensors in the intersecting direction. After the side edge of the sheet is detected, the moving means is further moved by the remaining distance necessary for setting the punching position to the punching position, and is stopped by the conveying means by the leading edge / rear edge detection sensor. In response to detection of the trailing edge of the conveyed sheet, the conveyance of the sheet by the conveyance unit is stopped, and then the punching process by the punching unit is executed. .

  In the punching device of the present invention, the punching process is performed by changing the start timing of the detection operation of the sheet side edge position information in response to a setting operation (including a command) through a switch, a keyboard, an operation panel, communication, or the like. Since the speed and the accuracy of the drilling position can be adjusted in a trade-off manner, the optimum balance between productivity and accuracy can be selected according to the processing contents, necessity, and conditions of each processing.

  If the start timing of the detection operation of the sheet side edge position information is delayed, the distance between the detection position on the sheet and the punching position is shortened, the deviation in the width direction is reduced, and the sheet is not easily affected by skewing or curling. In addition, since the possibility that a deviation in the width direction occurs in the time from detection to drilling is reduced, the accuracy in the width direction of the drilling position is increased, while the time for the detection operation by the detection means and the adjustment operation by the adjustment means is ensured. Therefore, it is necessary to stop and wait for the sheet conveyance, or to temporarily decrease the conveyance speed, and the total time for the punching process increases.

  On the other hand, if the start timing of the detection operation of the sheet side edge position information is advanced, the position detection operation time by the moving means can be sufficiently secured, so that the conveyance of the sheet is temporarily stopped or the conveyance speed is temporarily reduced. The total time required for punching processing is shortened, while the distance between the detection position on the sheet and the punching position becomes longer and the deviation in the width direction becomes larger. In addition, since the possibility of causing a shift in the width direction during the time from detection to drilling increases, the accuracy in the width direction of the drilling position decreases.

  Therefore, it is possible to select a mode that places importance on the hole position accuracy of the punch hole depending on the usage and orientation of the delivery user and a mode that maintains the productivity of the hole position accuracy as it is, and it is necessary to provide a special mechanism. Therefore, it is possible to respond to each user according to orientation without increasing the cost.

  A sheet processing apparatus B according to an embodiment of the present invention and a copying machine E as an embodiment of an image forming apparatus including the sheet processing apparatus B will be described with reference to the drawings. However, the sheet processing apparatus of the present invention is not limited to the stapling process of the present embodiment, and may be configured to simply stack the punched sheets on the sheet stacking means, and may be configured to perform other processes such as alignment and inspection. Alternatively, a configuration in which only other processing is performed or another configuration in which the same processing is performed may be performed. The image forming apparatus of the present invention is not limited to the copying machine E of the present embodiment, and may be implemented by a facsimile, a printer, various printing machines, and the like.

  Further, the sheet processing apparatus B of the present embodiment may be connected to a printing apparatus or the like other than the apparatus main body A of the copying machine E shown in FIG. 1, and the sheet processing apparatus B of the present embodiment is separated from the apparatus main body A. It may be configured as a separate case, or may be incorporated in the case of the apparatus main body A so as not to be separated.

<Image forming apparatus>
FIG. 1 is a front view of an image forming apparatus to which a sheet processing apparatus according to this embodiment is connected. The image forming apparatus of the present embodiment includes, for example, an apparatus main body A that is an image forming unit and a sheet processing apparatus B that is a processing unit.

  As shown in FIG. 1, the copying machine E is configured by connecting a sheet processing apparatus B to an apparatus main body A. The apparatus main body A optically reads a document automatically fed from the document feeder 1 provided on the upper portion of the apparatus main body A by the optical unit 2, converts the read signal into a digital signal, and converts an image signal and image data into an image. The image is transmitted to the forming unit 3 and the original image is copied onto a sheet P such as plain paper or overhead projector (OHP) paper.

  A plurality of sheet cassettes 4 that store sheets P of various sizes are provided in the lower part of the apparatus main body A. The sheet P in the sheet cassette 4 is fed into the image forming unit 3 by the conveyance roller 5. At this time, a latent image is formed on the photosensitive drum 3b of the image forming unit 3 by irradiating a laser beam modulated based on image information read by the optical unit 2 from the light irradiation unit 3a.

  The latent image on the photosensitive drum 3 b is developed with toner to become a toner image, and the toner image on the photosensitive drum 3 b is transferred to the sheet P sent to the image forming unit 3. Thereafter, the sheet P is conveyed to the fixing device 6, and heat and pressure are applied by the fixing device 6 to fix the toner image on the sheet P.

  In the single-sided recording mode in which an image is formed on only one side of the sheet P, the sheet P that has passed through the fixing device 6 is immediately sent from the apparatus main body A to the sheet processing apparatus B. However, in the double-sided recording mode in which images are formed on both sides of the sheet P, the sheet P on which the image is recorded on one side by the above processing operation is switched back and returned to the retransmission path 7 to form an image again. The image is formed on the other surface by being conveyed to the section 3. The sheet P on which images are formed on both sides is finally sent from the apparatus main body A to the sheet processing apparatus B. The sheet P can be supplied not only from the sheet cassette 4 but also from the multi-tray 8.

<Sheet processing device>
FIG. 2 is an explanatory diagram of a configuration of the sheet processing apparatus, FIG. 3 is a schematic diagram of a conveyance system of the sheet processing apparatus, and FIG. 4 is a block diagram of a control system of the sheet processing apparatus. The sheet processing apparatus B of the present embodiment includes, for example, a punch unit 40 that is a punching device and an adjustment unit, a sensor unit 41 that is a detection unit, a CPU 200 that is a control unit, a stack tray 18 that is a sheet stacking member, and a discharge member. For example, a downstream discharge roller pair 17 is provided.

  As shown in FIG. 2, when discharging the sheet P to the stack tray 18, the sheet processing apparatus B responds to each mode such as the punch mode and the staple mode in addition to the normal mode in which the sheet P is simply stacked. Sheet processing can be selected.

  In the normal mode, the downstream discharge roller pair 17 is maintained in a contact state, and the sheet P discharged from the apparatus main body A to the sheet processing apparatus B passes through the upstream discharge roller pair 16 from the conveying roller pair 15 and the downstream discharge roller pair 17. To the stack tray 18a (18b, 18c is also possible) by the downstream discharge roller pair 17 and stacked.

  In the punch mode, the sheet P discharged to the sheet processing apparatus B is temporarily stopped by the punch unit 40, and the punch unit 40 is operated one by one to form a binding hole on the rear end side of the sheet.

  In the sort mode, the sheets P are stacked on the staple tray 12 for each number of copies with the downstream discharge roller pair 17 being separated, sorted, and discharged to the stack tray 18a (18b and 18c are also acceptable).

  In the staple mode, the rear end side of the sheet bundle stacked and aligned on the staple tray 12 is stapled by the stapler 13 and then discharged to the stack tray 18a (18b and 18c are also acceptable).

  In the two-sheet discharge mode, the sheet P discharged to the sheet processing apparatus B stays in the buffer path 14 and is discharged simultaneously with the next sheet P to be discharged. Further, the sheet P punched in the punch mode can be stacked and aligned on the staple tray 12 and stapled by the stapler 13.

  The downstream discharge roller pair 17 can contact / separate the swinging roller 17b pivotally supported by the swinging guide 20 with respect to the stationary roller 17a as the swinging guide 20 rotates. Above the swing guide 20, a distance measuring sensor 54 for detecting the uppermost surface of the sheets P stacked on the stack tray 18a is provided. The distance measuring sensor 54 includes a light emitting unit that irradiates the sheet bundle with light rays such as infrared rays, and a light receiving unit that receives the light rays irregularly reflected by the sheet bundle, and measures the angle of the reflected light to reach the stacking surface. The distance can be detected.

  The three-stage stack trays 18a, 18b, and 18c are attached to and integrated with the tray frame 57, and are moved up and down by operating the pinion gear 225 by the stacker motor 209. In the sheet processing designating the stack tray 18a, the stack tray 18a is positioned at the sheet receiving position below the downstream discharge roller pair 17, and in the sheet processing designating the stack tray 18b, the sheet processing designating the stack tray 18b and the stack tray 18c. Then, the tray frame 57 is moved up and down so that the stack tray 18c is at the sheet receiving position.

  In the sort mode, the stacking surfaces of the stack trays 18a, 18b, and 18c are sequentially moved to the sheet receiving position, whereby the sheets P can be discharged in a state of being sorted for each number of copies. In the staple mode, it is possible to discharge the stapled sheet bundle to the stack trays 18a, 18b, and 18c in a sorted state.

  On the back side of the staple tray 12, a rear end stopper 33 that abuts and aligns the rear end of the sheets discharged to the staple tray 12, and a stapler that staples the rear end side of the bundle of sheets stacked on the staple tray 12. 13 are arranged. A side guide 11 is provided on the upper surface of the staple tray 12 to reciprocate in the sheet width direction and align the side edges of the sheets discharged to the staple tray 12.

  The knurled belt 32 disposed in contact with the upper surface of the staple tray 12 circulates in the same direction as the upstream discharge roller pair 16, and the rear end of the sheet discharged to the staple tray 12 by the upstream discharge roller pair 16 is used as the staple tray 12. Then, the sheet is rubbed and pulled back, and the rear end of the sheet is brought into contact with the rear end stopper 33.

  The buffer roller 23 can sandwich a sheet between the buffer roller 24 and wrap the sheet around two or three sheets of the buffer roller 23 to make the buffer path 14 stand by. The sheets waiting on the buffer roller 23 are collectively sent to the upstream discharge roller pair 16 by rotating the buffer roller 23 once in a state where the flapper 25 is tilted to the buffer roller 23 side.

  The leading and trailing edges of the sheet flowing into the upstream discharge roller pair 16 are detected by the discharge sensor 29. A carry-in sensor 28 is disposed downstream of the first transport roller 10, an entry sensor 27 is disposed at the entrance of the buffer path 14, and a buffer sensor 26 is disposed on the outer periphery of the buffer roller 23.

  A punch unit 40 is disposed on the upstream side of the first conveying roller 10, and a punch waste container 39 for storing punch waste generated by the punch unit 40 is disposed below the punch unit 40. A sensor unit 41 that detects the side edge of the sheet supplied to the punch unit 40 is disposed upstream of the punch unit 40. A switch 90 that switches the operation mode of the punch unit 40 between the productivity-oriented mode and the hole position accuracy-oriented mode is disposed above the punch unit 40.

  As shown in FIG. 3, the first conveyance roller 10 has a conveyance motor 211 and the lower discharge roller pair 17 and a discharge motor 208 have respective dedicated drive sources. The second conveyance roller 15, the upper discharge roller pair 16, the buffalo The roller 23 is driven by a drive motor 205.

  In the above-described two-sheet discharge mode, the leading sheet P2 waiting in the buffer path 14 and the trailing sheet P3 discharged from the apparatus main body A (FIG. 1) are conveyed so that the amount of deviation is constant. For this purpose, the rotation of the buffer roller 23 is started when the succeeding sheet P3 passes the position of the approach sensor 27 or when a predetermined clock has elapsed after the succeeding sheet P3 passes the approach sensor 27. In addition, the amount of deviation between the leading ends of the preceding sheet P2 and the succeeding sheet P3 is made constant.

In other words, in a state in which the driving motor 205 for driving the buffer roller 23 is stopped, since the first conveying roller 10 passes the entry sensor 27 located to convey the trailing sheet P3, the first conveying roller 10, the buffer roller 23 It is driven by a dedicated transport motor 211 different from the above.

  Further, in the stapling mode, the productivity of the apparatus main body A (FIG. 1) is not lowered. Therefore, after the sheet P is discharged from the apparatus main body A, the conveyance speed of the sheet P is increased, and the gap between the sheet P and the succeeding sheet P is increased. However, if the driving source of the first conveying roller 10 is shared with the driving sources of the other rollers, the succeeding sheet P is moved to the second sheet P before increasing the conveying speed of the sheet P. The advantage of reaching the one conveying roller 10 and increasing the sheet P conveying speed is lost. Therefore, the first transport roller 10 is driven by a dedicated transport motor 211.

  As shown in FIG. 4, the sheet processing apparatus B is controlled by a CPU (Central Processing Unit) 200. The CPU 200 includes a ROM 100, a RAM 101, and the like. The ROM 100 is a read-only storage element in which various programs and data for performing sheet processing including the processing of the flowcharts of FIGS. 10 to 13 are written. The RAM 101 is a storage element that can be written and erased. The RAM 101 holds a program read from the ROM 100, and process data and calculation results generated in the course of sheet processing are written and erased as needed.

  The input port of the CPU 200 includes the carry-in sensor 28, the approach sensor 27, the buffer sensor 26, the discharge sensor 29, the distance sensor 54, the stack sensor 53, the transmission sensor unit 41, the slide HP sensor 43, the switch 90, and others. These sensors and operation means are connected.

  The output port of the CPU 200 includes the transport motor 211, the drive motor 205, the discharge motor 208, the stacker motor 209, the staple motor 210 that drives the stapler 13, the side guide motor 207 that drives the side guide 11, and the first flapper solenoid 202. The second flapper solenoid 203, the paddle solenoid 206, the lateral registration motor 42, the punch motor 40f, and other motors and actuators are connected.

  The communication driver 102 connected to the CPU 200 performs serial communication with the apparatus main body A (FIG. 1), and exchanges various signals and sheet information such as a sheet size for operating the apparatus main body A and the sheet processing apparatus B in cooperation with each other. I do. When the user selects each required sheet processing mode in order to use the copying machine E through a liquid crystal touch panel operation unit (not shown) provided in the apparatus main body A, the apparatus main body A displays the set processing information and sheet. Information is transmitted to the CPU 200.

  The CPU 200 reads a necessary program from the ROM 100 and holds it in the RAM 101, communicates with the apparatus main body 100 through the communication driver 102, reads the above-described various sensor inputs, performs necessary calculations and determinations, and performs calculation results and determinations. Based on the results, the above-described various motors and actuators are operated to cause the sheet processing apparatus B to execute sheet processing in cooperation with the discharge of the apparatus main body A.

  The CPU 200 detects the distance from the output of the distance measuring sensor 54 to the uppermost surface of the sheets P (or sheet bundle) stacked on the stack tray 18a (or 18b, 18c), that is, the stacking surface, and this distance becomes a predetermined value. In this manner, the stacker motor 209 is operated to position the stacking surface of the stack tray 18a (or 18b, 18c) at a height position convenient for sheet discharge and stacking. When a predetermined number of sheets P are discharged to the stack tray 18a (or 18b, 18c) or a sheet bundle is discharged, the stack tray 18a (or 18b, 18c) is lowered by the thickness of the discharged sheet P or sheet bundle. Thus, the height of the loading surface is kept the same as before discharging.

<Punch unit>
5 is an enlarged cross-sectional view of the punch unit as viewed from the front, FIG. 6 is a plan view of the punch unit and the transmission sensor unit, FIG. 7 is an explanatory diagram of the operation of detecting the sheet side edge, and FIG. FIG. 9 is an explanatory diagram of sheet side edge detection in the hole position accuracy emphasis mode, FIG. 10 is a punch control flowchart, FIG. 11 is a punch control flowchart in the productivity emphasis mode, and FIG. 12 is hole position accuracy. FIG. 13 is a flowchart of the lateral registration sensor selection control. The sheet processing apparatus B, for example, a sheet processing apparatus of the present invention includes, for example, a punch unit 40 that is a punching means and an adjustment means, a sensor unit 41 that is a detection means, and a CPU 200 that is a control means.

  As shown in FIG. 5, in the punch unit 40, the cam 40b fixed to the drive shaft 40a rotates and moves the sliding frame 40c in the vertical direction, so that the punch 40d penetrates the lower frame 40e, The sheet between the guide 40f and the lower frame 40e is punched.

  The guide 40f and the lower frame 40e are disposed across the sheet conveyance path. The sliding frame 40c to which the punch 40d is fixed can move up and down with respect to the lower frame 40e in which the through hole of the punch 40d is formed, and is biased upward by a spring (not shown).

  When the punch motor 40f (FIG. 4) rotates, the rotation is transmitted to the drive shaft 40a, and the cam 40b held by the sliding frame 40c rotates to lower the punch 40d against the spring bias and lower frame 40e. The punch 40d passes through the hole provided in the. As a result, the sheet is perforated (perforated).

  As shown in FIG. 6, the transmissive sensor unit 41 is fixed to the punch unit 40, and has a rear end detection sensor 41a and lateral registration sensors 41b, 41c, 41d, and 41e that detect optical transmission and light shielding. is doing. The lateral registration sensors 41b, 41c, 41d, and 41e in the present embodiment have light receiving elements arranged at the side edge positions of the sheets P of B5, A4, B5R, and A4R sizes, and a light source that is perpendicular to the paper surface. , The sheet P discharged from the apparatus main body A is passed, and the side edge of the sheet P is detected according to the sheet size. The trailing edge detection sensor 41a detects the trailing edge of the sheet inside the lateral registration sensor 41b, and outputs a signal for positioning the punching position by the punch unit 40 with respect to the trailing edge of the sheet.

  The punch unit 40 slides in the direction of arrow C in the figure by the rotation of the lateral registration motor 42 by engaging a rack portion 40g provided in the punch unit 40 and a pinion gear 42a attached to the output shaft of the lateral registration motor 42. To do. When the punch unit 40 is positioned at the home position in the upward direction on the paper, the flag 40h attached to the rack portion 40g shields the lateral registration home sensor 43 from light.

  Next, a lateral registration operation related to punch hole position accuracy and productivity and its start timing will be described.

  As shown in FIG. 7, the punch unit 40 and the sensor unit 41 are initially outside the lateral registration sensors 41b, 41c, 41d, and 41e that detect sheets of each size detect the side edges of the sheets P of each size. Therefore, when the A4R size sheet P is discharged from the apparatus main body A and conveyed under the sensor unit 41, the lateral registration sensor 41e for detecting the A4R size is positioned outside the side edge of the sheet P. ing.

  When the leading edge of the sheet P shields the trailing edge detection sensor 41a and the trailing edge detection sensor 41a is turned on, the sheet register P is conveyed in a conveying direction indicated by an arrow in the drawing, and then the lateral registration motor 42 is activated to start the punch unit 40. Is started to move in the direction of arrow C in the figure. The lateral registration sensor 41e gradually approaches the side end surface of the A4R size sheet P and is shielded from light. The punch unit 40 continues to move to a position where the centers of the two punch holes coincide with the center of the sheet P. The lateral register motor 42 stops after moving a predetermined distance. As described above, since the side edge is detected for each sheet P and the punch unit 40 is positioned at the center of the sheet P, the punch hole is formed at the center of the sheet P with high accuracy without aligning the sheets P. it can.

  Next, the lateral registration operation in the productivity emphasis mode and the hole position accuracy emphasis mode will be described by taking as an example a case where the sheet P discharged from the apparatus main body A is extremely skewed. Here, the sheet P shown in FIG. 8 and the sheet P shown in FIG. 9 have the same skew feed amount.

  As shown in FIG. 8, in the productivity-oriented mode, after the leading edge of the sheet P is detected by the trailing edge detection sensor 41a, the conveyance distance until the detection of the side edge of the sheet P is shortened, in other words, from the punching position. However, by detecting the side edge of the sheet P quite forward, a sufficient time is ensured from when the lateral registration sensor 41e detects the side edge of the sheet P until the trailing edge detection sensor 41a detects the trailing edge of the sheet P. Therefore, the positioning of the punch unit 40 has already been completed when the trailing edge of the sheet P is detected by the trailing edge detection sensor 41a. Therefore, the conveyance of the sheet P can be stopped for the time required for the operation of the punch unit 40, and the punching can be completed. However, the center of the sheet P and the center of the punch unit 40 are shifted by a shift width x by the conveyance from the time when the lateral registration sensor 41e detects the side edge of the sheet P to the time when the trailing edge detection sensor 41a detects the trailing edge of the sheet P. Therefore, the hole position accuracy cannot be ensured.

  On the other hand, as shown in FIG. 9, in the hole position accuracy emphasis mode, detection of the side edge of the sheet P is started at the conveyance position just behind the trailing edge of the sheet P, whereby the center of the sheet P and the center of the punch unit 40 are detected. The misalignment can be accommodated within a misalignment width y smaller than that in the productivity-oriented mode, but the lateral registration sensor 41e detects the side edge of the sheet P and positions the punch unit 40 in a state where the conveyance of the sheet P is stopped. The conveyance stop time of P becomes longer, and the efficiency of sheet processing decreases.

  In other words, in the productivity-oriented mode, the side edge of the sheet is detected at an early stage, but if the side end surface of the sheet P is detected at an early stage, the skew of the sheet P is skewed. Because of the influence, as shown in FIG. 8, the deviation width of the actual side end position with respect to the detected side end position becomes large at the rear end portion of the sheet P.

  Conversely, in the hole position accuracy emphasis mode, as shown in FIG. 9, the displacement width y is small with respect to the side edge of the rear end portion of the sheet P, but the time for positioning the punching position of the sheet P by the punch unit 40 in the width direction. Therefore, a waiting time for stopping the sheet P is required. That is, since the punch unit 40 cannot be positioned while the sheet P is moving in the transport direction, the time during which the sheet P is stopped is longer than that in the productivity-oriented mode, and the subsequent stapling process is delayed. Due to a delay in preparation for receiving the next sheet P, the productivity of the sheet processing apparatus decreases.

  As shown in FIG. 4, the ROM 100 of the CPU 200 stores a program for the processes shown in the flowcharts of FIGS. The switch 90 can be switched between a productivity-oriented mode and a hole position accuracy-oriented mode. The CPU 200 detects the output of the sensor unit 41 and operates the lateral registration motor 42, the conveyance motor 211, and the drive motor 205 to detect the side edge of the sheet P by the sensor unit 41, and the center positioning of the punch unit 40. Then, the punch motor 40f is operated to punch the sheet P. These punch control operations will be described with reference to the flowcharts of FIGS.

  As shown in FIG. 10, when punch control is started (S101), the CPU 200 confirms the state of the switch 90 (S102), and when it is off (NO in S102), control of the punch productivity priority mode is performed. (S103) is on (YES in S102), the control in the hole position accuracy emphasis mode is started (S104). When either control is finished, the punch control is finished (S105).

  In the productivity-oriented mode control in step S103, referring to FIG. 8, as shown in FIG. 11, when the productivity-oriented mode control is started (S111), the sheet P discharged from the apparatus main body A is controlled. Wait until the leading edge is detected by the trailing edge detection sensor 41a (S112). When the leading edge of the sheet P is detected, the distance of the conveyance distance L (= the length of the sheet P in the conveyance direction−182 mm) in order to delay the lateral registration operation start timing as much as possible without affecting the productivity. Is waited for (S113). When this conveyance waiting is canceled, it becomes the timing of the lateral registration operation start, and the lateral registration sensor 41e corresponding to the sheet size is selected from the lateral registration sensors 41b, 41c, 41d, and 41e by a lateral registration sensor selection process (described later) shown in FIG. Is selected (S114). When the sheet size is B5, A4, B5R, the lateral registration sensors 41b, 41c, 41d are selected, respectively.

  The CPU 200 starts the forward rotation operation of the lateral registration motor 42 (S115), moves the sensor unit 41 to the center side, waits for the lateral edge of the sheet P to be detected by the lateral registration sensor 41e (S116), and waits for the sheet P Is detected (YES in S116), the lateral registration motor 42 is stopped after continuing the rotation of the lateral registration motor 42 by the remaining distance required for centering the punch unit 40 (S117). Thereby, the punch hole position in the direction orthogonal to the conveyance direction of the sheet P is guaranteed.

  After the end of the lateral registration operation for positioning the punch unit 40, the process waits for the trailing edge of the sheet P being continuously conveyed to be detected by the trailing edge detection sensor 41a (S118), and when the trailing edge of the sheet P is detected. (YES in S118) In order to obtain the punch hole position accuracy in the conveyance direction of the sheet P, the conveyance motor 211 and the drive motor 205 are stopped after waiting for the sheet to be conveyed by the remaining distance movement (S119). When the transport motor 211 and the drive motor 205 are stopped (YES in S120) and the punch hole position of the sheet P is determined, the punch motor 40f is operated to start the punch hole drilling operation (S121), and the punch hole punch is performed. Is finished (YES in S122), the control in the productivity-oriented mode is finished (S123).

  In the control of the hole position accuracy emphasis mode in step S104 (FIG. 10), as shown in FIG. 12 with reference to FIG. 8, when the control of the hole position accuracy emphasis mode is started (S131), the CPU 200 performs the production. In the same manner as in the control in the importance-oriented mode, it waits for the leading edge of the sheet P discharged from the apparatus main body A to be detected by the trailing edge detection sensor 41a (S132), and when the leading edge of the sheet P is detected (YES in S132). ), The conveyance is continued until the trailing edge of the sheet P reaches the position 10 mm before the trailing edge detection sensor comes off, and the conveyance motor 211 and the drive motor 205 are stopped (S133).

  When the conveyance motor 211 and the drive motor 205 are stopped and conveyance of the sheet P is stopped (YES in S134), the lateral registration sensor 41e corresponding to the sheet size is selected (S135), and the lateral registration motor 42 starts to rotate (S136). ) Waits for the lateral registration sensor 41e to detect the side edge of the sheet P (S137). When the side edge is detected (YES in S137), the movement of the remaining distance is started (S138). Then, after waiting for the necessary remaining distance (S139), when the centering of the punch unit 40 is completed (YES in S139), the lateral registration motor 42 is stopped (S140). Then, the conveyance motor 211 and the drive motor 205 are activated again to start conveyance of the sheet P at a conveyance speed of 475 mm / sec (S141), and wait for the trailing edge detection sensor 41a to detect the trailing edge of the sheet P. (S142). When the trailing edge of the sheet P is detected (YES in S142), the remaining distance for conveying the punching position of the sheet P to the punch unit 40 is conveyed, and the conveying motor 211 and the drive motor 205 are stopped. (S143).

  When the conveyance motor 211 and the drive motor 205 are stopped (YES in S144), the punch motor 40f is operated to punch the sheet P (S145), and the completion of the punching process is waited (S146), and the punching process is completed. Then (YES in S146), the control of the hole position accuracy priority mode is terminated (S147).

  In step S114 of FIG. 11 and step S135 of FIG. 12, the lateral registration sensor is selected according to the sheet size, as shown in the flowchart of FIG. When the lateral registration sensor selection control is started (S161), the CPU 200 detects the sheet size from the sheet information transmitted from the apparatus main body A, and the sheet is selected from the four lateral registration sensors 41b, 41c, 41d, and 41e according to the sheet width. Select one according to size.

  When the sheet width is less than 200 mm (YES in S162), the light source of the lateral registration sensor 41b is turned on (S165), and the output of the light receiving unit of the lateral registration sensor 41b is selected (S169). When the sheet width is 200 mm or more and less than 220.9 mm (YES in S163), the light source of the lateral registration sensor 41c is turned on (S166), and the output of the light receiving unit of the lateral registration sensor 41c is selected (S170).

  When the sheet width is 220.9 mm or more and less than 268 mm (YES in S164), the light source of the lateral registration sensor 41d is turned on (S167), and the output of the light receiving unit of the lateral registration sensor 41d is selected (S171). Finally, when the sheet width is 268 mm or more, the light source of the lateral registration sensor 41e is turned on (S168), and the output of the light receiving unit of the lateral registration sensor 41e is selected (S172).

  In the control in the hole position accuracy emphasis mode in the present embodiment, the lateral registration operation is performed at a position near the rear end of the sheet P. Therefore, compared with the control in the productivity emphasis mode in which the horizontal registration operation is performed far before the rear end. Accordingly, the deviation of the punching position due to the skew of the sheet and the deviation of the conveyance becomes small, and the positional accuracy of the punching position is higher than the control in the productivity-oriented mode. However, since the lateral registration operation of S135 to S140 is performed in a state where the conveyance of the sheet P is stopped, S135 is performed for each sheet as compared with the productivity-oriented mode control in which the lateral registration operation is performed in parallel with the conveyance. The control waiting time of S140 is added, and the number of sheets processed per minute (productivity) of the sheet processing apparatus B and the copying machine E is reduced accordingly.

  In addition, the hole position accuracy emphasis mode and the productivity emphasis mode can be easily switched by turning on / off the switch 90 without changing the configuration and processing program of the sheet processing apparatus B. There is no increase in hardware development costs, and it is possible to change the setting just before shipment and to have only one model in stock. In addition, it is easy to switch between the hole position accuracy emphasis mode and the productivity emphasis mode according to the daily work or the type of sheet at the delivery destination.

  In the control in the hole position accuracy emphasis mode in the present embodiment, the conveyance of the sheet P is continued at a conveyance speed that is one step lower, instead of stopping at the position before the trailing edge of the sheet P passes through the trailing edge detection sensor 41a. Thus, the side edge detection by the lateral registration sensor 41e and the positioning of the punch unit 40 may be completed before the punching position of the sheet P reaches the punch unit 40.

  In the present embodiment, the switch 90 is provided to switch between the productivity-oriented mode and the hole position accuracy-oriented mode, but the mode may be switched by inputting a command with a detachable keyboard. The CPU 200 may be configured to perform switching setting via the apparatus main body A through a liquid crystal touch panel operation unit (not shown) provided in the main body A.

  In this embodiment, the CPU 200 that is an arithmetic control device independent of the arithmetic control device (not shown) that controls each part of the device main body A to form an image is provided. The processing program of the sheet processing apparatus B may be installed and controlled in common.

  In this embodiment, the two modes, the productivity-oriented mode and the hole position accuracy-oriented mode, can be switched and set. However, three or more modes having different specific gravity between the productivity and the hole position accuracy can be set. May be.

  In the sheet processing apparatus according to the present embodiment, in response to the setting operation through the switch 90, the time from the start of sheet position detection by the sensor unit 41 to the start of punching by the punch unit 40 changes, so that the processing speed-oriented mode And an accuracy-oriented mode can be selected and set, so that it is possible to easily change the balance between the optimum productivity and accuracy according to the processing contents and necessity of the delivery destination and the situation of each processing.

  Since these selections are made possible by a slight change in the processing program of the sheet processing apparatus B, there is no need to provide a special mechanism or replace parts for each setting. It is possible to respond to each user's orientation without increasing costs.

1 is a front view of an image forming apparatus to which a sheet processing apparatus according to an exemplary embodiment is connected. It is explanatory drawing of a structure of a sheet processing apparatus. It is a schematic diagram of the conveyance system of a sheet processing apparatus. It is a block diagram of a control system of the sheet processing apparatus. It is the expanded sectional view which looked at the punch unit from the front. It is a top view of a punch unit and a permeation | transmission sensor part. It is explanatory drawing of operation | movement of a sheet | seat side edge detection. It is explanatory drawing of sheet | seat side edge detection in productivity priority mode. It is explanatory drawing of the sheet | seat side edge detection in hole position accuracy emphasis mode. It is a flowchart of punch control. It is a flowchart of punch control in the productivity emphasis mode. It is a flowchart of punch control in hole position accuracy emphasis mode. It is a flowchart of lateral registration sensor selection control.

Explanation of symbols

A Image forming means (apparatus body)
B Sheet processing device E Image forming device (copier)
40 Punching means (punch unit)
40f punch motor 41 detection means (sensor unit)
42 Adjustment means (lateral registration motor)
90 switching means (switch)
205 Drive motor 211 Conveyance motor 200 Control means (CPU)

Claims (3)

Conveying means for conveying the sheet in a predetermined direction along the conveying path;
A punching unit arranged to be movable in a crossing direction intersecting with the predetermined direction and performing punching processing at a punching position on a sheet conveyed by the conveying unit;
A side edge sensor for movably arranged sheet side edge detection to the the cross direction crossing the predetermined direction,
A front end / rear end detection sensor that is disposed inside the side end detection sensor in the intersecting direction and detects a front end and a rear end of a sheet conveyed by the conveyance unit;
Moving means for moving the side edge detection sensor and the punching means in the crossing direction;
An accuracy emphasis mode in which the moving means is operated in a state where conveyance by the conveying means is stopped and the side edge detection sensor detects the side edge of the sheet, and the moving means in a state where the sheet is conveyed by the conveying means Switching means for switching and setting productivity-oriented mode in which the side edge detection sensor detects the side edge of the sheet by operating
Is stopped by moving the perforating means to the drilling position by said moving means and said side end detecting sensor after detecting the side edge of the sheet, then, by conveying the sheet into the puncture hole position location by the transport means Control means for executing the punching process by the punching means, and a sheet processing apparatus comprising:
The side edge sensor is movable in the direction crossing the predetermined direction such that each is selected to correspond to different sheet sizes are arrayed together,
The moving means integrally moves the plurality of side edge detection sensors and the punching means in the crossing direction, and detects the side edge of the sheet by the side edge detection sensor selected corresponding to the sheet size. It said piercing means is set to the drilling position by further moving the plurality of the side edge sensor and said perforating means,
The control means temporarily stops the conveyance of the sheet by the conveying means in response to the detection of the leading edge of the sheet by the leading edge / rear edge detection sensor when the accuracy emphasis mode is set by the switching means. The side edge detection selected according to the sheet size by moving the punching means and the plurality of side edge detection sensors in the intersecting direction by operating the moving means in a state where the conveyance of the sheet is stopped. After the sensor detects the side edge of the sheet, it is further stopped by moving the remaining distance necessary for setting the punching means to the punching position by the moving means, and the conveyance of the sheet by the conveying means is resumed. the tip / rear end detecting sensor to stop the sheet conveyance by the conveying means in response to the trailing edge detection of the sheet by, then said perforations punished by the perforating means Was executed,
Also,
When the productivity-oriented mode is set by the switching means, the control means detects the leading edge of the sheet by the leading edge / rear edge detection sensor and then conveys the sheet by a predetermined distance by the conveying means. The movement means is started, the punching means and the plurality of side edge detection sensors are moved in the intersecting direction, and the side edge detection sensor selected corresponding to the sheet size detects the side edge of the sheet. Further, the moving means stops the punching means by moving the remaining distance required for setting the punching position to the punching position, and detects the trailing edge of the sheet conveyed by the conveying means by the leading edge / rear edge detection sensor. Accordingly, the sheet processing apparatus is configured to stop the conveyance of the sheet by the conveying unit and then execute the punching process by the punching unit. The front end / rear end detection sensors are arranged on a line of a plurality of side end detection sensors arranged in the intersecting direction, and are moved in the intersecting direction integrally with the plurality of side end detection sensors and the punching means by the moving means. the sheet processing apparatus according to claim 1, characterized in that it is. Image forming means for forming an image on a sheet;
An image forming apparatus comprising the a sheet processing apparatus according to any one of claims 1 or 2, perforated sheets formed an image by the image forming means.

Images