JP6318692B2 - Finisher, image forming apparatus, finisher control method, and computer program - Google Patents

Description

  The present invention relates to post-processing of paper on which an image is printed.

  Conventionally, a technique has been proposed in which sheets (sheets) on which images are printed are successively stacked on a discharge tray.

  According to the technique described in Patent Document 1, processing is performed as follows so that all types of sheets can be stacked satisfactorily. A sheet is discharged by a pair of discharge rollers whose sheet discharge speed is variably driven by a discharge motor. At the same time, the sheet discharge motor is controlled so that the sheet discharge speed of the stacking tray is decelerated so that the sheet discharge speed corresponding to the type of the sheet is obtained when the leading edge of the sheet comes into contact with the stacked sheet on the stacking tray. .

JP 2010-159124 A

  In recent years, downsizing of image forming apparatuses has been attempted. One way is to make the finisher compact.

  Thus, it is conceivable to superimpose a sheet of another print document to be post-processed on a print document composed of one or a plurality of sheets whose post-processing has been advanced. That is, it can be considered that the same space is shared by two sets of printed documents in different phases.

  However, it is necessary to prevent the two sets of print documents from being mixed by holding the previous print document with a member such as a nail.

  However, if a sheet of a later print document is fed onto this member, the image printed on the sheet may be rubbed and soiled.

  SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and an object of the present invention is to reduce the contamination of a subsequent print document by a member that holds the previous print document in the finisher.

A finisher according to an aspect of the present invention is a finisher that performs a discrimination process so that N sets (N ≧ 2) of printed documents including one or a plurality of sheets on which an image is printed by a printing apparatus are not mixed with each other. A storage unit for storing a print document of a K-th group (where 1 ≦ K ≦ N) sent from the printing apparatus, and the storage unit from the first position at the first speed at the fastest speed. An elevating mechanism for raising to a second position or lowering from the second position to the first position; and when the enclosure is in the first position, the enclosure stored in the enclosure A distinction processing mechanism for performing the distinction process on the K-th set of printed documents, and the storage unit from the first position to the second position of the K-th set of print documents subjected to the distinction process. A holding member for holding when ascending to After the distinction process has been performed on the printed document of the eye, the enclosure rises at a second speed that is slower than the first speed or starts to rise when a certain time has elapsed. A controller that controls the elevating mechanism ; and a guide member that guides the first sheet of the (K + 1) -th set of printed documents sent out from the printing apparatus in the direction of the second position, The controller controls the elevating mechanism so that the housing finishes rising after the first sheet of the (K + 1) th set of printed documents has been guided by the guide member.

  Alternatively, the controller controls the elevating mechanism so that the container finishes raising when the first sheet of the (K + 1) -th set of printed documents has been guided by the guide member.

  Alternatively, when the N sets of printed documents are stored in the storage unit, the controller raises the storage unit immediately after the discrimination processing is performed on the N sets of printed documents. The lifting mechanism is controlled as follows.

  Or a discharge mechanism that discharges the K-th set of printed documents to a predetermined location after the container has been raised to the second position; After starting to be discharged to the predetermined place, the elevating mechanism is controlled so that the container is lowered to the first position.

  Alternatively, the discrimination processing mechanism performs a process of binding the K-th set of printed documents with staples as the discrimination process.

  According to the present invention, it is possible to reduce the contamination of the subsequent printed document by the member that holds the previous printed document in the finisher.

1 is a diagram illustrating an example of an appearance of an image forming apparatus. 2 is a block diagram illustrating an example of a hardware configuration of an image forming apparatus. FIG. FIG. 3 is a schematic diagram illustrating an example of a configuration of a print unit. It is a perspective view which shows the example of a structure of a post-processing apparatus. It is a block diagram which shows the example of a structure of a post-processing apparatus. It is a figure which shows the state before a raise of a post-processing apparatus. It is a figure which shows the state after the raise of a post-processing apparatus. It is a figure which shows the example of the default timing of operation | movement of a post-processing apparatus. It is a figure for demonstrating the principle in which the image printed on the paper gets dirty. It is a figure which shows the example of the timing of operation | movement of a post-processing apparatus at the time of reducing dirt. FIG. 10 is a diagram illustrating an example of a state of temporary storage (pre-stacking) of paper in a raised paper discharge tray. It is a flowchart explaining the example of the flow of the whole process in a post-processing apparatus. It is a flowchart explaining the example of the procedure of a process of a 2nd phase and a 3rd phase.

  FIG. 1 is a diagram illustrating an example of the appearance of the image forming apparatus 1. FIG. 2 is a block diagram illustrating an example of a hardware configuration of the image forming apparatus 1. FIG. 3 is a schematic diagram illustrating an example of the configuration of the print unit 2. FIG. 4 is a perspective view showing an example of the configuration of the post-processing device 3. FIG. 5 is a block diagram illustrating an example of the configuration of the post-processing device 3.

  An image forming apparatus 1 shown in FIG. 1 is an image processing apparatus generally called an MFP (Multi Function Peripherals) or a multifunction peripheral, and is an apparatus that integrates functions such as a copy, a network print, a fax, a scanner, and a document server. is there.

  As shown in FIG. 1 or 2, the image forming apparatus 1 includes a main CPU (Central Processing Unit) 10a, a RAM (Random Access Memory) 10b, a ROM (Read Only Memory) 10c, a mass storage device 10d, a NIC (Network Interface Card) 10e, modem 10f, touch panel display 10g, operation key panel 10h, scan unit 10i, print unit 2, and post-processing device 3.

  The ROM 10c or the large-capacity storage device 10d stores an operating system for controlling the entire image forming apparatus 1 and applications for realizing the above functions. Furthermore, software for transmitting data related to post-processing described later to the post-processing device 3 is also stored.

  Programs constituting these software are loaded into the RAM 10b as necessary and executed by the main CPU 10a. A hard disk drive, SSD (Solid State Drive), or the like is used as the mass storage device 10d.

  The NIC 10e communicates with other devices via a LAN (Local Area Network) or the Internet using a protocol such as TCP / IP (Transmission Control Protocol / Internet Protocol).

  The modem 10f communicates with other devices via a telephone line using a protocol such as G3.

  The touch panel display 10g displays a screen for giving a message to the user, a screen showing a result of processing, a screen for the user to input an instruction to the image processing apparatus 1, and the like. Further, the touched position is detected, and the position is notified to the CPU 10a.

  The operation key panel 10h includes keys for inputting commands such as a start key, a stop key, and a function key.

  The scan unit 10i includes an ADF (Auto Document Feeder), a scanner, platen glass, and the like. The ADF sends out the set original sheets one by one to the scanner. The scanner reads an image such as a document, a photograph, a picture, or a chart recorded on a sheet sent from the ADF, and generates image data of the document. The scanner can also read the image of the paper set on the platen glass and generate image data of the document.

  As shown in FIG. 3, the print unit 2 includes a paper feed tray 20, a delivery roller 21, a development unit 22, a print head unit 23, a toner cartridge 24, a primary transfer roller 25, a transfer belt 26, a timing roller 27, and a secondary transfer roller. 28, a fixing device 29, and a discharge roller 2A.

  Hereinafter, of the four side surfaces of the image forming apparatus 1, the surface on which the touch panel display 10g and the operation key panel 10h are provided is assumed to be the front surface, and the position or direction of each part is represented.

  The paper feed tray 20 stores a plurality of sheets on which nothing is printed, that is, blank sheets. The sending roller 21 sends the sheets from the sheet feeding unit 20 one by one to the timing roller 22.

  The developing unit 22 is provided for each of yellow, magenta, cyan, and black colors, and forms an image of each color. Hereinafter, the development units 22 for yellow, magenta, cyan, and black may be described separately as “development unit 22Y”, “development unit 22M”, “development unit 22C”, and “development unit 22K”.

  The developing unit 22 includes a charging charger 22a, a photoreceptor 22b, a developing device 22d, and the like. The charging charger 22a charges the surface of the photoreceptor 22b to a uniform potential.

  The print head unit 23 forms an electrostatic latent image by irradiating each photoconductor 22b whose surface is uniformly charged with light corresponding to the color image of each photoconductor 22b. For example, a yellow electrostatic latent image is formed by irradiating the photoconductor 22b of the developing unit 22Y with light corresponding to the yellow image.

  The developing device 22d electrostatically attracts toner to the portion of the photoreceptor 22b where the electrostatic latent image is formed.

  The toner cartridge 24 (24Y, 24M, 24C, 24K) is provided for each of yellow, magenta, cyan, and black colors, and supplies toner of each color to the developing device 22d. For example, the toner cartridge 24Y supplies yellow toner to the developing device 22d of the developing unit 22Y.

  The primary transfer rollers 25 (25Y, 25M, 25C, and 25K) are provided for each color of yellow, magenta, cyan, and black, and transfer the toner adsorbed to each photoreceptor 22b to the transfer belt 26 (primary transfer). )

  The timing roller 27 temporarily stops the paper conveyed from the delivery roller 21. Then, the toner transferred to the transfer belt 26 is sent out at a timing so that the secondary transfer roller 28 transfers the toner to a predetermined position on the sheet.

  The secondary transfer roller 28 transfers (secondary transfer) the toner transferred to the transfer belt 26 to the paper transported from the timing roller 27. Then, this sheet is sent to the fixing device 29.

  The fixing device 29 heats the sheet sent from the secondary transfer roller 28 to fix the toner on the sheet, and sends it to the discharge roller 2A.

  Then, the discharge roller 2 </ b> A sends the paper sent from the fixing device 29 to the post-processing device 3. Hereinafter, the paper on which the image is printed by the print unit 2 is referred to as “paper 4”. At this time, the lower surface of the paper 4 is the printing surface.

  As the print unit 2, a known tandem and electrophotographic printing apparatus is used.

  Returning to FIGS. 1 and 2, the post-processing device 3 does not staple a set of print documents 5 made up of a plurality of sheets 4 generated by the print unit 2, or mixes each set of print documents 5. Sort and discharge. That is, the post-processing device 3 is a finisher (FNS) that performs post-processing.

  As shown in FIG. 4 or FIG. 5, the post-processing apparatus 3 includes a front end alignment plate 301, a rear end alignment plate 302, a front alignment plate 303, a rear alignment plate 304, a push plate 305, a stapler 32, a paper discharge tray 33, a sheet A holding claw 34, a prestack plate 35, a paper tray 36, and the like are included. Further, in order to control these, the FNS CPU 30a, RAM 30b, ROM 30c, front end alignment plate drive unit 371, rear end alignment plate drive unit 372, front alignment plate drive unit 373, back alignment plate drive unit 374, push plate drive unit 375, a stapler driving unit 376, a paper discharge tray driving unit 377, a paper holding claw driving unit 378, a prestack driving unit 379, and the like.

  The ROM 30c stores a post-processing program 30P (see FIG. 12) for post-processing such as stapling and sorting described above.

  The post-processing program 30P is loaded into the RAM 30b and executed by the FNS CPU 30a.

  Hereinafter, the role of each part of the post-processing device 3 shown in FIG. 4 or FIG.

[Main functions of each part]
FIG. 6 is a diagram illustrating a state before the post-processing device 3 is raised. FIG. 7 is a diagram illustrating a state after the post-processing device 3 is lifted.

  In particular, FIGS. 6A and 7A are cross-sectional views of the post-processing device 3 taken along a plane parallel to the front, and FIGS. 6B and 7B show the post-processing device. It is a top view when 3 is seen from the top. Note that portions not related to the present invention are omitted.

  The paper discharge tray 33 stores the paper 4 discharged from the discharge roller 2A. In order to perform post-processing on a set of printed documents 5 composed of a plurality of sheets 4, these sheets 4 are stored.

  As shown in FIGS. 6A and 7A, an elevating member 3771 is provided under the paper discharge tray 33. The sheet discharge tray drive unit 377 moves the sheet discharge tray 33 up and down by moving the other end up and down around one end of the lifting member 3771.

  The leading edge alignment plate 301, the trailing edge alignment plate 302, the front alignment plate 303, and the back alignment plate 304 adjust the position of the paper 4 and move the paper 4.

  The leading end alignment plate drive unit 371, the rear end alignment plate drive unit 372, the front alignment plate drive unit 373, and the back alignment plate drive unit 374 respectively include a front end alignment plate 301, a rear end alignment plate 302, a front alignment plate 303, and The back alignment plate 304 is moved.

  The stapler 32 binds the print document 5 with staples. The stapler driving unit 376 drives the stapler 32.

  Two paper holding claws 34 are arranged in the rear direction from the front (front side), and support the printed document 5 from the upstream side so that the printed paper 5 does not slide down when the paper discharge tray 33 rises. Further, the paper holding claw 34 can move to the top of the print document 5 so that the paper 4 of other print documents 5 is not mixed. The paper holding claw driving unit 378 drives the paper holding claw 34.

  The extrusion plate 305 pushes the printed document 5 that has been post-processed to the paper tray 36. The extrusion plate driving unit 375 drives the extrusion plate 305.

  The prestack plate 35 moves up and down around the right end. The prestack driving unit 379 drives the prestack plate 35. In particular, the prestack plate 35 is raised when the discharge tray 33 is raised, and is lowered when the discharge tray 33 is lowered. Thereby, even before a set of print documents 5 is pushed out to the paper tray 36, the paper 4 of the next print document 5 can be stored in the paper discharge tray 33.

  For example, a motor is used as each driving unit of the leading end alignment plate driving unit 371 to the prestack driving unit 379. Some of the plurality of driving units may be realized by sharing one motor. For example, when the paper discharge tray 33 is lowered as shown in FIG. 6, the pusher plate 305 and the back aligning plate 304 may be connected, and the pusher plate driving unit 375 may operate the back aligning plate 304.

  The leading edge alignment plate driving unit 371 to the prestack driving unit 379 are controlled by the FNS CPU 30a based on the post-processing program 30P.

[When multiple sets of printed documents are post-processed without considering contamination reduction]
FIG. 8 is a diagram illustrating an example of the default timing of the operation of the post-processing device 3. FIG. 9 is a diagram for explaining the principle that an image printed on the paper 4 is stained.

  Next, the operation of each unit when post-processing a plurality of sets of printed documents 5 without decelerating will be described with reference to the timing chart of FIG.

  Post-processing mainly consists of the following three phases. The first phase is a phase in which the paper 4 of the set of print documents 5 is stored in the paper discharge tray 33. The second phase is a phase in which the sheet 4 of the set of printed documents 5 is stapled as necessary and moved to a position for sorting. The third phase is a phase in which the print document 5 is discharged to the paper tray 36.

  Hereinafter, a case where A4 size plain paper is used as the paper 4 will be described as an example. In FIG. 8, “conveying” means that the paper 4 is being conveyed by the discharge roller 2A. More specifically, during the time period in which the conveyance is on, the paper 4 is discharged by the discharging roller 2A. This is a time period from the start of discharging to the time when the sheet is placed in the discharge tray 33.

  The FNS CPU 30a receives post-processing target data 20D from the main CPU 10a. Further, the timing at which the paper 4 is discharged from the discharge roller 2A is notified from the main CPU 10a or the print unit 2. Then, the FNS CPU 30a controls the leading end alignment plate driving unit 371 to the prestack driving unit 379 based on the post-processing target data 20D, the notified timing, and the post-processing program 30P.

  Note that the post-processing target data 20D indicates information related to the print document 5 that is the target of post-processing. Specifically, the number of sheets 4, the size, and the paper quality of each set of print documents 5 are shown. In some cases, a mode (for example, gloss mode) or an image characteristic (for example, a photographic image) at the time of printing may be further indicated.

  Before the time when the first sheet 4 of the first set of printed documents 5 is discharged from the discharge roller 2A (time Pa in FIG. 8), the leading end alignment plate driving unit 371 to the prestack driving unit 379 Each part is arranged at a predetermined position as follows. Hereinafter, the nth sheet of the m-th printed document 5 is described as “sheet 4mn” in particular. Thus, for example, the second sheet 4 of the first set of print documents 5 is “sheet 412”.

  The leading end alignment plate drive unit 371, the rear end alignment plate drive unit 372, the front alignment plate drive unit 373, and the back alignment plate drive unit 374 respectively include a front end alignment plate 301, a rear end alignment plate 302, a front alignment plate 303, and The back alignment plate 304 is moved to each standby position corresponding to the size of the paper 411. The standby position is a position about 20 millimeters away from each end of the area where the paper 411 falls on the paper discharge tray 33.

  The extrusion plate driving unit 375, the stapler driving unit 376, the paper discharge tray driving unit 377, the paper holding claw driving unit 378, and the prestack driving unit 379 are respectively the extrusion plate 305, the stapler 32, the paper discharge tray 33, and the paper holding claw. If the 34 and the prestack plate 35 are not at the home position, they are moved to the home position.

  As shown in FIG. 6B, the home position of the push-out plate 305 is slightly further (for example, several millimeters) than the position before the printed document 5 is pushed out, that is, the back end of the paper discharge tray 33. The position of the direction.

  As shown in FIG. 6A, the home position of the stapler 32 is a standby posture and position for stapling, that is, a state where the mouth is opened. The home position of the paper discharge tray 33 is a position completely lowered. The home position of the paper holding claw 34 is a position where the tip is hidden below the upper surface of the paper discharge tray 33. The home position on the prestack plate 35 is a position completely lowered.

  When the paper 411 is discharged from the discharge roller 2A (time Pa in FIGS. 8A and 8B) and dropped onto the paper discharge tray 33 (time Pb), the leading edge aligning plate driving unit 371 and the leading edge aligning plate 301 are rearward. The leading end alignment plate 301 is moved upstream, that is, in the right direction so that the distance from the end alignment plate 302 is the length of the paper 411 in the traveling direction (main scanning direction during printing). Further, the front alignment plate driving unit 373 and the back alignment plate driving unit 374 are arranged so that the distance between the front alignment plate 303 and the rear alignment plate 304 is the length in the sub-scanning direction when printing the paper 411. 303 and the back alignment plate 304 are moved. As a result, the sheet 411 is arranged at a fixed position for forming a bundle with the other sheets 4. Hereinafter, arranging at this fixed position is referred to as “alignment”.

  Each unit of the post-processing device 3 aligns the second and subsequent sheets 4 in the same manner as the sheet 411. When the first set of printed documents 5 is composed of two sheets 4, the sheet 412 is also discharged from the discharge roller 2A (time Pc) and is aligned when dropped onto the sheet discharge tray 33 (time Pd). As a result, the ends of the sheets 411 and 412 are aligned.

  When the alignment of the last sheet 4 (the sheet 412 in the above example) of the print document 5 is completed, the following processing is performed depending on whether or not stapling is necessary.

  When binding the print document 5 with staples, the front end alignment plate driving unit 371 and the rear end alignment plate driving unit 372 move the front end alignment plate 301 and the rear end alignment plate 302 to the downstream side (to the left) to perform printing. The document 5 (paper 411, 412) is moved to the position of the stapler 32. The leading edge aligning plate 301 has a mechanism that can pinch the end of the print document 5, and when the print document 5 is moved downstream, it is pinched and moved.

  When the movement of the print document 5 is completed, the stapler driving unit 376 operates the stapler 32 so as to staple, and further retracts the stapler 32 in the back direction.

  When the staple binding is completed, the front end alignment plate driving unit 371 and the rear end alignment plate driving unit 372 move the front end alignment plate 301 and the rear end alignment plate 302 to the left by a predetermined distance. As a result, the print document 5 moves to the stapling sorting position. With the above process, the second phase is completed (time Pe).

  On the other hand, when the printed document 5 is not bound with staples, the leading end alignment plate driving unit 371 and the trailing end alignment plate driving unit 372 move the leading end alignment plate 301 and the trailing end alignment plate 302 to the left by a predetermined distance. Thus, the print document 5 is moved to the sorting position. For example, the odd-numbered set of printed documents 5 is moved by a distance La, and the even-numbered set of printed documents 5 is moved by a distance Lb. However, the distance La ≠ the distance Lb. As a result, it is possible to sort the two consecutive printed documents 5 so that they do not overlap exactly.

  With the above processing, the second phase is completed (time Pe ′). When the second phase is completed, a process (third phase) for conveying the print document 5 to the paper tray 36 is performed as follows.

  The paper holding claw driving unit 378 drives the paper holding claw 34 so that the front end is located above the printing document 5 while supporting the printing document 5 from the upstream side, and the paper discharge tray driving unit 377 shows the paper discharge tray 33. Raise like 7 (A). In parallel, the prestack driving unit 379 raises the prestack plate 35.

  When the ascent is completed (time Pf, Pf ′), the paper holding claw driving unit 378 drives the paper holding claw 34 so as to release the print document 5, and the extrusion plate driving unit 375 moves the extrusion plate 305 forward (front side). ) Operate at high speed in the direction. As a result, the print document 5 is pushed out to the paper tray 36.

  After the extrusion, for the next set of printed documents 5, the leading edge alignment plate driving unit 371 to the prestack driving unit 379 move each unit to the home position (HP). Then, the first sheet 4 of the next set of printed documents 5 is also lowered with the discharge tray 33. The leading end alignment plate 301 and the like are aligned by pinching and moving the sheet 4 as appropriate. Each unit then waits for the second sheet 4 to be sent.

  By the way, during the second phase of the printed document 5 of a certain group (in this example, the first group), the first sheet 4 of the printed document 5 of the next group (in this example, the second group). (In this example, the paper 421) may be discharged from the discharge roller 2A. Since the prestack plate 35 is in the raised state, a part of the downstream side (left direction) of the paper 421 is on the upstream side (right direction) of the first set of printed documents 5 stored in the raised paper discharge tray 33. May overlap part.

  In this case, as shown in FIG. 9A, the paper 421 may be sent out from the discharge roller 2A while the printing surface is in contact with the paper holding claw 34. The paper holding claw 34 is slightly sharpened. Therefore, the toner in the portion of the printed image that comes into contact with the paper holding claw 34 may be rubbed and stains such as streaks as shown in FIG. 9B may occur. Specifically, a portion that contacts the paper holding claw 34 after the time Pf or the time Pf ′ may be stained.

  Therefore, each part of the post-processing device 3 performs the following processing on the paper 4 and the print document 5 so as to reduce the contamination.

[When post-processing printed matter to reduce smudges]
FIG. 10 is a diagram illustrating an example of the timing of the operation of the post-processing device 3 when reducing dirt. FIG. 11 is a diagram illustrating an example of a state in which the paper 4 is temporarily stored (pre-stacked) in the raised paper discharge tray 33.

  The FNS CPU 30a controls each unit as follows at the timing shown in FIG. Each unit of the post-processing device 3 is controlled so that the first set of printed documents 5 is stapled as necessary and moved to a predetermined position. The timing of the process so far is the same as the timing shown in FIG.

  When the movement is completed (time Pt), the paper discharge tray driving unit 377 moves the first sheet 4 (the first set of print documents 5 of the next set) on the set of print documents 5 (the first set in this example). In this example, the discharge tray 33 starts to rise at a timing so that the rise of the discharge tray 33 is completed at the time Pv when the paper 421) stops. Hereinafter, this timing is referred to as “rise timing”.

  Incidentally, the sheet 4 is discharged from the discharge roller 2A at intervals of a predetermined time Ta. For example, A4 size plain paper is discharged every 1.50 seconds. When the paper discharge tray 33 is disposed at the home position as shown in FIG. 6A, after the paper is discharged from the discharge roller 2A, the paper is placed in the paper discharge tray 33 after a substantially fixed time has elapsed. Then, as soon as it is placed in the paper discharge tray 33, the alignment is started. Therefore, the time at which the alignment starts is a predetermined time after the paper 4 starts to be discharged (the time it takes for the paper 4 to be stored in the paper discharge tray 33 after being discharged from the discharge roller 2A. Hereinafter, “time Tb”. Is written).

  Further, the sheet 4 is disposed at a position where the sheet discharge tray 33 is raised as shown in FIG. 7A. After the sheet 4 begins to be discharged from the discharge roller 2A, a substantially constant time (hereinafter referred to as “time”). Is written in the paper discharge tray 33 as shown in FIG.

  Further, the time required for alignment of the paper 4, the time required for moving the printed document 5 to the stapler 32, and the time required for moving the printed document 5 to the sorting position are substantially constant. Therefore, the time required for the second phase is determined to be substantially constant according to the contents of the second phase.

  When stapling is required, time Td is the time required for the second phase, as shown in FIGS. 8A and 10A. In the case of the first set of printed documents 5, the time from time Pd to time Pe or time Pr to time Pt is time Td. The time required for the second phase of the other set of printed documents 5 is also approximately equal to the time Td.

  When stapling is not required, as shown in FIGS. 8B and 10B, the time Td ′ is the time required for the second phase. Time Pe ′ or time Pr to time Pt ′. When the time for movement varies depending on the sorting position, the time Td 'is determined for each sorting position.

  Further, the time required for raising the paper discharge tray 33 from the state shown in FIG. 6A to the state shown in FIG. 6B is also substantially constant. Hereinafter, this time is referred to as “time Te”.

  These times are obtained in advance by performing a post-processing test using A4 size plain paper as the paper 4, and collecting and analyzing data on the operation of each part of the post-processing device 3 and the position of each paper 4. be able to.

  Based on these times, the above-described rising timing is determined in advance. That is, as shown in FIG. 10 (A) or (B), after the second phase is started (that is, after the alignment of the last sheet 4 of the print document 5 is started), the time Ta-time Te has elapsed. This time is determined in advance as the rising timing.

  According to this rising timing, the sheet 4 (in this example, the sheet 421) does not hit the sheet holding claw 34 while it is moving, so that the contamination due to contact with the sheet holding claw 34 can be reduced more than before. Can do.

  When the ascent is completed (time Pf, Pf ′), the paper holding claw 34 releases the print document 5 and the pusher plate 305 moves at a high speed in the front (front) direction, as in the case where the reduction of dirt is not considered. As a result, the print document 5 is pushed out to the paper tray 36.

  In the example of FIG. 10, the rising timing is set so that the rising of the discharge tray 33 is completed when the first sheet 4 of the next set of print documents 5 is stored in the discharge tray 33. If it is slower than the default, it may be slightly different.

[When using other forms of paper 4]
The printing speed varies depending on the characteristics of the paper. Therefore, the discharge interval of the paper 4 from the discharge roller 2A also changes, and the rising timing changes accordingly. Hereinafter, two examples of changing the rising timing will be described.

(1) Letter-size plain paper When letter-size plain paper is used as the paper 4, the A4 size plain paper is used as the paper 4 for the time Ta (interval of discharging the paper 4 from the discharge roller 2A). Slightly shorter than the case. For example, if the time Ta is 1.5 seconds for A4 size plain paper, it becomes 1.42 seconds for letter size plain paper, and the time Tb is shortened. Therefore, the rising timing is slightly earlier than in the case of A4 size plain paper.

(2) A4 size thick paper When an A4 size thick paper is used as the paper 4, the time Ta is longer than when the A4 size plain paper is used as the paper 4, and the rising timing is delayed. For example, if the time Ta is doubled, the rising timing is delayed by a double time.

  It is preferable that the speed of raising the paper discharge tray 33 is slower as the speed of discharging the paper from the discharge roller 2A is slower. For example, if the discharge speed of A4 size thick paper is one half of the discharge speed of A4 size plain paper, the speed of raising the discharge tray 33 in the case of A4 size thick paper is set as follows. In the case of A4 size plain paper, the speed of raising of the discharge tray 33 is reduced to one half.

[If the printed image is easily scratched]
In the above example, even when the paper discharge tray 33 is raised to discharge the print document 5 to the paper tray 36, the first paper 4 of the next print document 5 is discharged by the prestack plate 35. It was stored in the tray 33.

  According to the above-described rising timing, the paper 4 can be prevented from being rubbed against the paper holding claw 34, but the paper 4 touches the paper holding claw 34. Then, depending on the printed image or the characteristics of the paper 4, the image may be damaged.

  Therefore, in the following case, the print unit 2 decreases the printing speed and lengthens the interval for discharging the paper 4 from the discharge roller 2A.

  Specifically, the interval is set so that the first sheet of the next print document 5 is discharged from the discharge roller 2A after the discharge tray 33 is raised and lowered to discharge the print document 5 to the paper tray 36. Determine. Since the printing speed is sufficiently slow (the interval is sufficiently long), the default timing for raising the discharge tray 33 may be used. In other words, it may be increased immediately after the second phase is completed.

  The following four are examples of forms in which printed images are easily damaged. The first form is a form in which a high-density image is printed in the vicinity of 140 millimeters (for example, in a range of 140 ± 10 millimeters) from the rear end (upstream side) of the paper 4.

  In the “high density image”, the total frequency of appearance per dot of the toner used for each color (yellow, magenta, cyan, and black) exceeds a threshold value. Since the toner of the high density image is difficult to dry, it is necessary to take a sufficient interval for discharging the paper 4. For example, when the frequency of appearance of yellow, magenta, cyan, and black in the vicinity is 20%, 30%, 40%, and 50% and the threshold is 100%, a high-density image is present in this vicinity. It is determined that it is printed. The threshold value may be changed according to room temperature and humidity. For example, when the room temperature is 30 ° C. or higher and the humidity is 60% or higher, the toner is easy to dissolve and difficult to dry because of high temperature and high humidity, so a higher value (for example, 130%) may be used as the threshold value. .

  The second form is a form in which a so-called photographic image is printed on the paper 4. As with the high-density image, the photographic image is difficult to dry the toner, so it is necessary to allow a sufficient interval for discharging the paper 4.

  The third form is a form in which paper 4 such as glossy paper or photographic paper, on which the fixed toner is difficult to dry, is used.

  In the fourth form, plain paper or thick paper is used as the paper 4 and printing is performed in the gloss mode. In the gloss mode, in order to increase the smoothness of the image surface, more toner is used than in the normal mode, and fixing is performed at a low temperature. Therefore, since the toner fixing property is lower than that in the normal mode, it is necessary to allow a sufficient interval for discharging the paper 4.

  FIG. 12 is a flowchart for explaining an example of the overall processing flow in the post-processing device 3. FIG. 13 is a flowchart for explaining an example of the processing procedure of the second phase and the third phase.

  Next, the overall processing flow for the paper 4 will be described with reference to the flowcharts of FIGS.

  The FNS CPU 30a executes the following process according to the post-processing program 30P. When the post-processing target data 20D is received from the main CPU 10a (# 11 in FIG. 12), each unit is operated as follows based on the post-processing target data 20D.

  Initialization processing such as retreating each part to the home position is performed (# 12). When the sheet 4 is sent from the discharge roller 2A (# 13 Yes), if this sheet 4 is not the last sheet of the print document 5 (No in # 14), the leading edge alignment plate 301, the trailing edge alignment plate 302, and the near edge alignment The sheet 4 is aligned by the plate 303 and the back alignment plate 304 (# 15, # 16). Then, the process returns to step # 13 and waits for the next sheet 4 to be sent.

  On the other hand, when the paper 4 sent from the discharge roller 2A is the last paper of the print document 5 (Yes in # 14), the processing of the second phase and the third phase shown in FIG. 13 is performed (#). 17).

  The sheet 4 is aligned by the leading edge alignment plate 301, the trailing edge alignment plate 302, the front alignment plate 303, and the back alignment plate 304 (# 701, # 702). The printed document 5 is moved to a predetermined position in the downstream direction by the leading edge alignment plate 301 and the trailing edge alignment plate 302 (# 703).

  If the staple mode is on (Yes in # 704), the printed document 5 is bound by the stapler 32 (# 705), and moved to a predetermined position by the leading edge alignment plate 301 and the trailing edge alignment plate 302 (# 706).

  If the next sheet 4 is sent from the discharge roller 2A (Yes in # 707), and the next sheet 4 is not in a form in which the image is easily damaged (No in # 708), the default The rising timing is determined so as to be later than the rising timing (# 709), and the discharge tray 33 is raised at this rising timing (# 712). Then, the printing document 5 is pushed out to the paper tray 36 by the push plate 305 (# 713), and the paper discharge tray 33 is lowered and returned to the home position (# 714).

  On the other hand, when the form of the next sheet 4 is a form in which the image is easily damaged (Yes in # 708), the rising timing is determined as the default timing for this form (# 710). Then, the paper discharge tray 33 is raised at this rising timing, the printed document 5 is pushed out to the paper tray 36 by the pusher plate 305, and the paper discharge tray 33 is returned to the home position (# 712 to # 714). According to this rising timing, the next sheet 4 is discharged from the discharge roller 2 </ b> A after the discharge tray 33 is lowered, so that it does not hit the sheet holding claw 34.

  If the next sheet 4 is not sent (No in # 707), the rising timing is determined as the timing when the reduction of the stain is not considered (see FIG. 8) (# 711). Then, the paper discharge tray 33 is raised at this rising timing, the printed document 5 is pushed out to the paper tray 36 by the pusher plate 305, and the paper discharge tray 33 is returned to the home position (# 712 to # 714).

  If there is a next print document 5 (Yes in # 18 of FIG. 12), the process returns to step # 13 and waits for the next paper 4 to be sent.

  According to the present embodiment, it is possible to reduce the contamination of the paper 4 of the subsequent print document by the paper holding claw 34 when the paper holding claw 34 holds the previous print document 5 as compared with the conventional case.

  In the present embodiment, as can be seen by comparing FIG. 8 and FIG. 10, when the first sheet 4 of the next set of printed documents 5 is stored in the discharge tray 33, the discharge tray 33 rises. To complete, the timing was adjusted by delaying the rising timing without changing the speed at which the paper discharge tray 33 was raised. However, the adjustment may be made by slowing the speed of raising the discharge tray 33 without changing the rising timing.

  In the present embodiment, as shown in FIG. 6A, the prestack plate 35 rises together with the discharge tray 33 because the end portion is below the end portion of the discharge tray 33 at the home position. However, the configuration may be such that the end portion of the prestack plate 35 is on the upper side and the prestack plate 35 is raised before the paper discharge tray 33.

  In addition, the entire image forming apparatus 1, print unit 2, post-processing apparatus 3, configuration of each unit, processing content, processing order, and the like can be changed as appropriate in accordance with the spirit of the present invention.

DESCRIPTION OF SYMBOLS 1 Image forming apparatus 2 Print unit (printing apparatus, printing mechanism)
3 Post-processing equipment (finisher)
4 Paper 5 Printed document 30a FNS CPU (controller)
301 Tip alignment plate (discrimination processing mechanism)
302 Rear end alignment plate (discrimination processing mechanism)
305 Extrusion plate (discharge mechanism)
32 Stapler (Difference processing mechanism)
33 Output tray (container)
34 Paper holding claws (holding members)
35 Pre-stack board (guide member)
371 Tip alignment plate drive (discriminating mechanism)
372 Rear end alignment plate driving unit (discrimination processing mechanism)
375 Extrusion plate drive (discharge mechanism)
377 Paper discharge tray drive (lifting mechanism)

Claims (11)

A finisher that performs distinction processing so that N sets (N ≧ 2) of print documents composed of one or a plurality of sheets on which images are printed by a printing apparatus are not mixed with each other,
A storage unit for storing printed documents of the K-th group (where 1 ≦ K ≦ N) sent out from the printing device;
An elevating mechanism that raises the storage device from the first position to the second position at the first speed at the fastest speed, or descends from the second position to the first position;
A distinction processing mechanism for performing the distinction processing on the K-th set of print documents stored in the storage when the storage is in the first position;
A holding member that holds the K-th set of printed documents subjected to the distinction process when the container is raised from the first position to the second position;
After the distinction process is performed on the K-th set of printed documents, the storage unit rises at a second speed slower than the first speed or starts to rise when a specific time has elapsed. A controller for controlling the elevating mechanism;
A guide member for guiding the first sheet of the (K + 1) set of print documents sent out from the printing apparatus in the direction of the second position;
The controller controls the elevating mechanism so that the housing finishes rising after the first sheet of the (K + 1) set of printed documents is guided by the guide member;
Finisher, wherein a call. The controller controls the elevating mechanism so that the container finishes moving up when the first sheet of the (K + 1) set of printed documents has been guided by the guide member;
The finisher according to claim 1. When the N sets of printed documents are stored in the storage unit, the controller causes the storage unit to rise immediately after the discrimination processing is performed on the N sets of printed documents. Controlling the lifting mechanism;
The finisher according to claim 1 or 2. A discharge mechanism that discharges the K-th set of printed documents to a predetermined location after the container has been raised to the second position;
The controller controls the elevating mechanism so that the storage unit is lowered to the first position after the K-th set of printed documents starts to be discharged to the predetermined location.
The finisher according to any one of claims 1 to 3. The discrimination processing mechanism performs a process of binding the K-th set of print documents with staples as the discrimination processing.
The finisher according to any one of claims 1 to 4. The discrimination processing mechanism performs, as the discrimination processing, a process of shifting the position of the K-th set of print documents so as not to be exactly overlapped with the (K + 1) -th set of print documents.
The finisher according to any one of claims 1 to 4. The second speed is determined according to the type of the paper.
The finisher according to any one of claims 1 to 6. The controller causes the storage to rise at the first speed when the (K + 1) -th set of printed documents is a dirty document and is sent out from the printing device later than the other documents. Controlling the lifting mechanism;
The finisher according to any one of claims 1 to 7. An image having a printing mechanism and a finisher that performs a distinction process so that N sets (N ≧ 2) of print documents made of one or a plurality of sheets on which images are printed by the printing mechanism are not mixed with each other. A forming device,
In the finisher,
A container for storing a K-th set of printed documents sent out from the printing mechanism;
An elevating mechanism that raises the storage device from the first position to the second position at the first speed at the fastest speed, or descends from the second position to the first position;
A distinction processing mechanism for performing the distinction processing on the K-th set of print documents stored in the storage when the storage is in the first position;
A holding member that holds the K-th set of printed documents subjected to the distinction process when the container is raised from the first position to the second position;
After the distinction process is performed on the K-th set of printed documents, the storage unit rises at a second speed slower than the first speed or starts to rise when a specific time has elapsed. A controller for controlling the elevating mechanism;
A guide member for guiding the first sheet of the (K + 1) -th set of printed documents sent out from the printing mechanism in the direction of the second position;
Is provided,
The controller controls the elevating mechanism so that the housing finishes rising after the first sheet of the (K + 1) set of printed documents is guided by the guide member;
An image forming apparatus. A finisher control method for performing a distinction process so that N sets (where N ≧ 2) of print documents including one or a plurality of sheets on which an image is printed by a printing apparatus are not mixed with each other,
The finisher includes
A storage for storing a K-th set of print documents sent out from the printing apparatus;
An elevating mechanism that raises the storage device from the first position to the second position at the first speed at the fastest speed, or descends from the second position to the first position;
A distinction processing mechanism for performing the distinction processing on the K-th set of print documents stored in the storage when the storage is in the first position;
A holding member that holds the K-th set of printed documents subjected to the distinction process when the container is raised from the first position to the second position;
A guide member for guiding the first sheet of the (K + 1) -th set of printed documents sent out from the printing apparatus in the direction of the second position;
Is provided,
After the distinction process is performed on the K-th set of printed documents, the storage unit rises at a second speed slower than the first speed or starts to rise when a specific time has elapsed. Control the elevating mechanism so that
Controlling the elevating mechanism so that the housing finishes rising after the first sheet of the (K + 1) set of printed documents has been guided by the guide member;
A finisher control method characterized by the above. A storage unit for storing one or a plurality of K sets of printed documents sent out from the printing apparatus, and the storage unit is raised from the first position to the second position at the first speed at the highest speed; Or an elevating mechanism for lowering from the second position to the first position, and the K-th set of printed documents stored in the storage when the storage is in the first position. A distinction processing mechanism for performing distinction processing for distinguishing from the (K + 1) th set of printed documents, and the storage unit stores the Kth set of printed documents subjected to the distinction processing from the first position. a holding member for holding at the time of rise to the second position, a guide member for guiding the first sheet paper of (K + 1) th group of printed document fed from the printing apparatus to the direction of the second position , A computer used to control a finisher having A-menu data program,
In the computer,
After the distinction process is performed on the K-th set of printed documents, the storage unit rises at a second speed slower than the first speed or starts to rise when a specific time has elapsed. So as to execute a first control process for controlling the lifting mechanism,
The (K + 1) th group of such first sheet Paper for printing documents wherein the storage unit finishes rising since when it has finished being guided by the guide member, a second control process for controlling the elevating mechanism To execute,
A computer program characterized by the above.

Images