JP4285359B2 - Image forming system and conveyance control method in image forming system - Google Patents

Description

  The present invention relates to an image forming system such as a copying machine, a printer, a facsimile machine, and a multi-function machine having these functions. In particular, a stapling process, a folding process, and a staple and a folding are combined for a sheet on which an image is formed. The present invention relates to an image forming system equipped with a post-processing device that performs post-processing such as processing to be performed and bookbinding processing.

  Paper conveyance control in an image forming system equipped with a post-processing device that performs post-processing such as stapling processing, folding processing, and bookbinding processing should satisfy both the conditions in the image forming device and the conditions in the post-processing device. To be done.

  The conditions in the main body of the image forming apparatus are mainly determined by the paper feeding capability of the paper feeding unit and the image forming capability of the image forming unit, and the sheet conveyance speed and the interval between the sheets are the paper feeding capability and the image forming capability. Is set by

  The condition in the post-processing apparatus is mainly the time required to form a plurality of sheet bundles. That is, in stapling, folding, bookbinding, and the like, sheets discharged one by one from the image forming apparatus main body are accumulated in an intermediate stacker, and post-processing is performed after the number of sheets in one processing unit is aligned. Since the first sheet of the subsequent processing unit cannot be carried into the post-processing apparatus until the sheet bundle of the previous processing unit is discharged from the intermediate stacker after the first sheet is carried into the post-processing apparatus, It is necessary to make the time from the carry-in of the last paper of the previous processing unit into the post-processing device to the post-processing device of the first paper of the subsequent processing unit longer than the time until the intermediate stacker becomes empty.

And have you in the image forming apparatus equipped with a post-processing apparatus, is then related to the transport control efficiently execute image formation, there are various devices conventionally.

  In Japanese Patent Laid-Open No. 2004-228688, there is provided means for recognizing the time required for post-processing, and based on the time recognized by the recognizing means, the leading paper of the subsequent processing unit from the transport start time of the final paper of the previous processing unit. It has been proposed to control the time until the conveyance start time.

  Japanese Patent Application Laid-Open No. 2005-228867 proposes that in a job for forming a plurality of images, the presence / absence of post-processing is determined for each copy, and the image formation timing is controlled based on the presence / absence of post-processing.

Japanese Patent Application Laid-Open No. 2004-228561 proposes that in the control of the transport start time when transporting a sheet to the image forming unit, a post-processing condition is added to other paper feed conditions, and the transport start time is set by ANDing various conditions. Has been.
JP-A-11-208979 JP 2001-215858 A Japanese Patent Laid-Open No. 2002-154685

  The conveyance control disclosed in Patent Documents 1 and 2 will be specifically described with reference to FIG.

  For example, as described in paragraph (0050) of Patent Document 1, in Patent Documents 1 and 2, the time used for post-processing in image formation in which an image is formed on a plurality of sheets and post-processing is performed. To set the interval between the last sheet of the first part (hereinafter referred to as the first copy) and the first sheet of the rear part (hereinafter referred to as the second copy). The processing allocation time is set.

  FIG. 1 (a) shows an example of creating two copies of three sheets.

  In FIG. 1, a black circle is a conveyance start time when paper feeding is performed, a white circle is a time corresponding to the conveyance time when paper feeding is not performed, t is a paper interval, T is a reference time, and U is a post-processing application time. The sheet interval t is the time from the leading edge (or trailing edge) of the preceding sheet to the leading edge (or trailing edge) of the succeeding sheet, and the reference time T is the front and The time used as a reference when setting the interval between the following subsequent parts, the post-processing application time U, is a time reserved for post-processing.

  As is well known, the sheet interval t is set by the sheet feeding speed of the sheet feeding unit, the image forming speed of the image forming unit, and the like, and is set as a basic specification of the image forming apparatus and is created by an interval timer.

  Since the post-processing in the present invention is performed in units of copies, the time from the conveyance of the final paper of the previous unit to the conveyance of the final paper of the subsequent unit is the post-processing application time U. The post-processing application time U is required to include the minimum time U0 necessary for the post-processing. If the post-processing application time U is shorter than the minimum time U0, the post-processing is impossible.

  Note that all the times in the figure are passing times in the registration rollers (secondary paper feeding unit), and these times are controlled by the registration rollers.

  In the conventional examples of Patent Documents 1 and 2, the reference time T is set as the time between the first sheet (first part) last paper s13 and the second part (rear part) leading paper s21. Then, transport control is performed to always ensure the reference time T. In the control of FIG. 1, the minimum time U0 required for post-processing is 10 seconds, and the reference time T is 10 seconds equal to the minimum time U0.

  In FIG. 1A, as a result of setting t = 1 sec, T = 10 sec, and T = 10 sec, U = 12 sec. The time V from the first sheet to the last sheet as a whole is 14 sec.

  FIG. 1B shows an example in which a first copy composed of three sheets and a second copy composed of five sheets are formed. In the example of FIG. 1B, as a result of setting the reference time T to 10 seconds, the post-processing application time U is 14 seconds. The time V from the first sheet to the last sheet as a whole is 16 sec.

  FIG. 1C shows an example in which a first set of five sheets and a second set of three sheets are formed. In the example of FIG. 1C, as a result of setting the reference time T to 10 seconds, the post-processing application time U is 12 seconds. The time V from the first sheet to the last sheet as a whole is 16 sec.

  Since the minimum time U0 required for the post-processing is 10 sec, the post-processing allocation time U in FIG. 1A is 12 sec. The post-processing allocation time U includes an extra time of 2 sec, and FIG. ) Includes an extra time of 4 seconds, and in FIG. 1C, an extra time of 2 seconds is included. Accordingly, the total image formation time becomes longer, and the efficiency becomes lower.

  As described above, in the conveyance control of Patent Documents 1 and 2, the post-processing application time U becomes unnecessarily long, and the efficiency decreases.

  Next, the conveyance control in Patent Document 3 will be specifically described with reference to FIG.

  In Patent Document 3, the time from the first copy of the first sheet to the second copy of the first sheet is set as the reference time T. Also in FIG. 2, the minimum time U0 required for post-processing is 10 seconds, and the reference time T is 10 seconds equal to the minimum time U0. In this conveyance control, in the case of image formation of three sheets for the first copy and three copies for the second copy, as shown in FIG. 2A, the post-processing application time U is 10 seconds equal to the minimum time U0. However, in the image formation of the first three copies and the second five copies, the post-processing application time U is 12 sec as shown in FIG. That is, in the conveyance control of Patent Document 3, in the example of FIG. 2A, the post-processing application time U is equal to the minimum time U0 and does not include an extra time, but in the example of FIG. The appropriation time U includes an extra time of 2 seconds, and the total image formation time is increased accordingly, and the efficiency is lowered. That is, in the example of FIG. 2A, V = 12 sec, and in FIG. 2B, V = 14 sec.

  Further, in the conveyance control of Patent Document 3, in the case of image formation of the first five sheets and the second three sheets, as shown in FIG. 2C, the post-processing application time U is 8 sec, which is necessary for the post-processing. It becomes shorter than the minimum time U0 (10 sec), and post-processing becomes impossible.

  As described above with reference to FIGS. 1 and 2, in the case of performing image formation with post-processing that forms a unit by bundling a plurality of sheets, the conventional conveyance control allows extra time and efficiency. There are problems such as low or low post-processing.

  SUMMARY OF THE INVENTION An object of the present invention is to solve such problems in conventional conveyance control, and to provide an image forming system that performs image formation with post-processing with high efficiency and a conveyance control method in the image forming system.

The object is achieved by the invention described in the following claims.
(Claim 1)
An image forming apparatus for forming an image on paper; and
A post-processing device that performs post-processing for collecting a plurality of sheets of paper on which an image has been formed is set, and a transfer start time is set in the image forming apparatus when the paper is transferred toward the image forming unit. In an image forming system provided with a paper feed control means for
The post-processing apparatus includes an intermediate stacker that stacks a plurality of sheets and a post-processing step unit that performs post-processing on a sheet bundle, and after stacking a plurality of sheets on the intermediate stacker, the stacked sheets The bundle is transported to the post-processing step part for post-processing,
When forming multiple paper bundles in succession,
The paper feed control means calculates the product of the paper interval, which is the interval between the front and rear papers, and the number of papers in one post-processing unit as the paper bundle after the start of discharging the previous paper bundle from the intermediate stacker. If the waiting time until loading is possible is less than or equal to the minimum time required for post-processing, the time from the start of transport of the last sheet of the previous sheet bundle to the start of transport of the last sheet of the subsequent sheet bundle The image forming system is characterized in that the final sheet conveyance start time of the subsequent sheet bundle is set so as to be equal to the shortest time required for post-processing .
(Claim 2)
The image forming system according to claim 1, wherein the sheet interval is generated by a timer that outputs an interval signal at a predetermined time interval.

According to the invention of claim 1 or 2, the time required for post-processing in an image forming system including a post-processing device that collects a plurality of sheets and creates a bundle of sheets, such as stapling, folding, and bookbinding. However, it is always ensured, there is no wasted time, a short image formation time is set, and highly efficient image formation is performed.

  Next, the overall configuration of the image forming system according to the embodiment of the present invention will be described with reference to FIG.

  FIG. 3 is an overall configuration diagram of an image forming system including the image forming apparatus A, the sheet post-processing apparatus FS, the sheet cutting apparatus B, and the glue binding apparatus C.

  The illustrated image forming apparatus A includes an image reading unit 1, an image processing unit 2, an image writing unit 3, an image forming unit 4, a storage unit 5, a paper feeding unit 6, a fixing device 7, a paper discharge unit 8, and a rear surface conveyance. Part 9 and the like.

  An automatic document feeder DF is mounted on the upper part of the image forming apparatus A. A sheet post-processing device FS including a sheet cutting device B and a gluing bookbinding device C is connected to the paper discharge unit 8 side on the left side of the image forming apparatus A shown in the drawing.

  The document d placed on the document table of the automatic document feeder DF is conveyed in the direction of the arrow, and an image on one or both sides of the document is formed by the optical system of the image reading unit 1 and read by the CCD image sensor 1A.

  The analog signal photoelectrically converted by the CCD image sensor 1A is subjected to analog processing, A / D conversion, shading correction, image compression processing, and the like in the image processing unit 2 and then sent to the image writing unit 3.

  In the image writing unit 3, output light from the semiconductor laser is irradiated onto the photosensitive drum 4 </ b> A of the image forming unit 4 to form a latent image. In the image forming unit 4, processes such as charging, exposure, development, transfer, separation, and cleaning are performed. The paper S carried out by the primary paper supply unit 6A from the storage unit 5 for storing the paper S is supplied to the image forming unit 4 by the secondary paper supply unit 6B made of registration rollers, and the image is transferred by the transfer means 4B. The sheet S carrying the image is fixed by the fixing device 7 and sent from the paper discharge unit 8 to the sheet post-processing device FS. Alternatively, the single-sided image-processed paper S sent to the back-side paper supply unit 9 by the transport path switching plate 8A is again discharged from the paper output unit 8 after double-sided image processing in the image forming unit 4, and the paper post-processing device FS. , The saddle stitching process and the half-folding process are performed, and then the sheet cutting apparatus B is sent.

  The paper post-processing device FS includes a shift processing device 21, an intermediate stacker 22, an additional paper feeding unit 23, a stapling processing device 24, a center folding device 25, a fixed paper discharge tray 26, and a lift paper discharge tray 27.

  The sheet S discharged from the image forming apparatus A is introduced from the introduction unit 20 to the sheet post-processing apparatus FS. The post-processed paper is discharged to the lifting / lowering tray 27 in the large-volume image forming motor and the post-processing mode, and is discharged to the fixed discharge tray 26 in the small-volume image forming mode.

  In the shift processing mode, shift processing is performed by the shift processing device 21 and the sheet is discharged onto the lifting / lowering tray 27. In the binding processing mode, the sheets S discharged from the image forming apparatus A one by one or fed from the additional sheet feeding unit 23 are stopped by the stopper 22A, and a set number of sheets are accumulated and accumulated on the intermediate stacker 22. The bundle of sheets S is stapled by the staple processing device 24 and then discharged to the lifting / discharging tray 27. From the additional paper feeding unit 23, the bundle of sheets S supplied from the image forming apparatus A is subjected to the shift process and the binding process in which the cover sheet and the insert sheet S are supplied, and the sheet is discharged to the lifting / discharging tray 27. Is done.

  In the bookbinding mode, the paper S supplied from the image forming apparatus A and the paper S supplied from the additional paper feeding unit 23 are stopped by the stopper 22B and accumulated on the intermediate stacker 22 by the set number. A bundle of the set number of sheets S is conveyed to the half-folding section 25, and after being folded with the central portion of the sheet S as a fold line, it is discharged and sent to the sheet cutting device B.

  The sheet cutting apparatus B includes a primary conveyance unit 30, a secondary conveyance unit 31, and a cutting machine 32. The cutting device 32 cuts the ends of the bundle of sheets S and aligns the ends.

  A bundle SA of sheets S introduced from the primary transport unit 30, cut by the cutting machine 32, transported by the secondary transport unit 31 and discharged from the paper cutting device B is introduced into the gluing bookbinding device C.

  The gluing bookbinding apparatus C includes a conveyance support unit 40, a gluing machine 41, and a pressure machine 42.

  The sheet bundle SA sent from the cutting device B to the gluing device C is conveyed by the conveyance support unit 40 and the end thereof is set below the gluing machine 41, and then the gluing by the gluing machine 41 is performed. The sheet bundle SA that has been pressed is pressed in a state where it is superimposed on the previous sheet bundle SA by the pressurizing machine 42 and coupled to the previous sheet bundle SA.

  In this way, after the booklet SB in which a plurality of sheet bundles SA are combined is formed, the booklet SB is discharged from the glue binding apparatus C.

  FIG. 4 is a block diagram of a control system of the image forming system shown in FIG.

  The image forming apparatus 100 is a control system of the image forming apparatus A in FIG. 3 and includes a printer control unit 101, a status management unit 102, an image processing unit 103, and a paper feeding unit 104. The printer control unit 101 performs control to form an image on a sheet, and includes a sheet feed control unit 101A and timers 101B and 101C. The timer 101B is an interval timer that generates the paper interval t in FIGS. 5 and 6 and outputs a signal having a continuous interval t. The sheet interval t is set according to the sheet feeding capability of the primary sheet feeding unit 6A, the image forming speed of the image forming unit 4, and the like.

  The image processing unit 103 processes the image data from the image reading apparatus 200 and creates image data for each page. The state management unit 102 transmits the image data for each page from the image processing unit 103 in synchronization with image formation in the printer control unit 101. The paper feeding unit 104 starts and stops the secondary paper feeding unit 6B in FIG. 3 based on a command from the printer control unit 101.

  The post-processing apparatus 300 is a control system for the post-processing FS, the sheet cutting apparatus B, and the glue binding apparatus C in FIG. 3, and includes a post-processing control unit 301, a stacker control unit 302, and a post-processing unit 303.

  The stacker control unit 302 controls the stacking of sheets in the intermediate stacker 22 of FIG. 3, and specifically controls the stoppers 22A and 22B to control the stacking of sheets and the discharge of the stacked sheets. The post-processing unit 303 controls the shift processing device 21, the staple processing device 24, the center folding device 25, the paper cutting device B, and the paper gluing device C.

  FIG. 5 is a time chart of paper conveyance in the image forming system shown in FIG.

  The sheet feeding control unit 104 that controls the secondary sheet feeding unit 6B provided upstream of the transfer unit 4B performs conveyance control for conveying the sheets S on which images are recorded one by one.

  Image formation is performed on the three sheets S11, S12, and S13 conveyed by the secondary sheet feeding unit 6B, and the sheets are collected on the intermediate stacker 22 to form a sheet bundle SA1. The sheet bundle SA1 is sent to the pressurizing unit 42 after undergoing each process of folding in the folding unit 25, cutting by the cutting machine 32, and gluing by the gluing machine 41.

  When the sheet bundle SA1 is discharged from the intermediate stacker 22 and the next sheet can be supplied to the intermediate stacker 22, the sheets S21 to S23 on which the next images are formed are supplied to the intermediate stacker 22 and the intermediate stacker 22 A sheet bundle SA2 is formed on the stacker 22. The sheet bundle SA2 is supplied to the pressurizing device 42 after undergoing each process of half-folding, cutting, and gluing. On the pressurizer 42, the sheet bundles SA1 and SA2 are combined to create a booklet SB.

  FIG. 6 is a diagram for explaining the conveyance control in the embodiment of the present invention.

  As described with reference to FIG. 1, also in FIG. 6, t is the sheet interval, T is the reference time, and U is the post-processing application time. Also, the time shown in FIG. 6 is the time when the paper S is started to be transported by the secondary paper feed unit 6B, and is the time controlled by the paper feed control means 104. The paper interval t is made by the timer 101B in FIG. 4, and the reference time T is made by the timer 101C in FIG. The sheet interval t has a value corresponding to the sheet size.

Also in the example illustrated in FIG. 6, t = 1 sec is a time when the black circle is the time when the secondary paper feeding unit 6B transports the paper, and a white circle is a time corresponding to the time when the paper is not transported, which is necessary for the post-processing. The minimum time U0 is 10 seconds.

  In the present invention, the reference time T is the time from the transport start time of the last sheet (first copy) to the transport start time of the last sheet (second copy).

In the example shown in the drawing, the reference time T is 10 seconds equal to the shortest time U0 required for post-processing. However, the reference time T may not equal to the shortest time U0, the reference time T is expressed by the following equation.
T = n × t + α
t is the sheet interval, n additional time, including the number of sheets per unit of processing in the post processing, alpha is 0,
In the example of FIG. 6, α = 3 .

  In the case of image formation of 3 sheets for the first copy and 3 copies for the second copy in FIG. 6A, the reference time T = 10 sec and the post-processing application time U = 10 sec. Not.

In FIG. 6A, the waiting time W 1 from the last sheet S13 of the first copy to the first sheet S21 of the second copy , that is, α is the second set of sheets after the first set of sheets are carried out from the intermediate stacker. This is a waiting time until S can be carried into the intermediate stacker. The waiting time W is a time that is generated when the conveyance speed of a sheet bundle composed of a plurality of sheets is lower than the conveyance speed for conveying one sheet, and it is necessary to take a value that is much larger than the sheet interval t. Absent.

  In the example of image formation for the first three copies and the second copy five images in FIG. 6B, the reference time T = 10 sec and the post-processing application time U = 10 sec. Not included.

  In the example of the image formation of the first five sheets and the second three sheets in FIG. 6C, the reference time T = 10 sec and the post-processing application time U = 10 sec. Not included.

  The total time V required for image formation is also V = 12 sec, 3 copies for the first copy, 5 copies for the second copy in the example of FIG. In the example of FIG. 6C with V = 12 sec, first copy 5 sheets and second copy 3 sheets, V = 14 sec.

  Table 1 summarizes the conveyance control in the present invention and the conveyance control in the conventional example.

  As can be seen from Table 1, in any case, the transport control of the present invention has a total time shorter than that of the conventional example, and the efficiency is improved. Moreover, it does not become uncontrollable.

  FIG. 7 is a flowchart of the conveyance control shown in FIG. The control shown in FIGS. 6 and 7 is performed by the paper feed control means 101A in FIG.

  In STEP1, when the paper interval time t set in the timer 101B is up, the process proceeds to STEP2. As shown in FIG. 6, the paper interval t is a time created by the timer 101B, which is an interval timer that outputs a signal at a constant time interval, and not only when paper is conveyed (black circle) but also when paper is not conveyed It is set by the interval signal that is also output to (white circle).

In STEP 2, it is detected whether or not it is the start of final paper conveyance for one copy, that is, one post-processing unit. If it is not the final sheet, it is detected in STEP 3 whether or not the reference time T is up. As described above, the reference time T is a time set based on the time required for the post-processing, and in the example of FIG. 6, is the time equal to the minimum post-processing time U0.
When the end of the set is detected in STEP 2 or when the reference time T has expired in STEP 3, the transport of the first sheet of the subsequent bundle is started, and a timer 101B that generates the sheet interval t and a timer 101C that generates the reference time T Set.

  The image forming system shown in FIG. 3 is an example in which a plurality of sheets are stacked on the intermediate stacker 22 and the staple processing device 24 performs the binding process on the intermediate stacker 22. In the present invention, a plurality of sheets are combined. Can be applied to various post-processing devices that perform post-processing, such as those that only perform stapling, those that perform only folding processing, those that perform stapling and folding processing, and those that perform gluing, etc. It can be applied to.

  FIG. 8 shows such a post-processing device or a unit used as part of such a post-processing device.

  In FIG. 8, the post-processing device FS has an intermediate stacker 22. A set number of sheets S discharged from the image forming apparatus are stacked on the intermediate stacker 22, and when the stacking is completed, the sheet bundle is conveyed to the next post-processing section, for example, a staple processing section or a folding section. Processing is performed.

It is a figure explaining the conveyance control in a prior art. It is a figure explaining the conveyance control in a prior art. 1 is an overall view of an image forming system according to an embodiment of the present invention. FIG. 4 is a block diagram of a control system of the image forming system shown in FIG. 3. 5 is a time chart of conveyance control in the image forming system shown in FIGS. It is a figure explaining conveyance control in the image forming system concerning an embodiment of the invention. It is a flowchart of the conveyance control shown in FIG. It is a figure which shows the other example of the post-processing apparatus in embodiment of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 101 Printer control part 101A Paper feed control means 102 Status management part 103 Image processing part 104 Paper feed part t Paper interval T Reference time

Claims (2)

An image forming apparatus for forming an image on paper; and
A post-processing device that performs post-processing for collecting a plurality of sheets of paper on which an image has been formed is set, and a transfer start time is set in the image forming apparatus when the paper is transferred toward the image forming unit. In an image forming system provided with a paper feed control means for
The post-processing apparatus includes an intermediate stacker that stacks a plurality of sheets and a post-processing process unit that performs post-processing on a sheet bundle, and stacks a plurality of sheets on the intermediate stacker and then stacks the sheets. The bundle is transported to the post-processing step part for post-processing,
When forming multiple paper bundles in succession,
The paper feed control means calculates the product of the paper interval, which is the interval between the front and rear papers, and the number of papers in one post-processing unit as the paper bundle after the start of discharging the previous paper bundle from the intermediate stacker. If the waiting time until loading is possible is less than or equal to the minimum time required for post-processing, the time from the start of transport of the last sheet of the previous sheet bundle to the start of transport of the last sheet of the subsequent sheet bundle The image forming system is characterized in that the final sheet conveyance start time of the subsequent sheet bundle is set so as to be equal to the shortest time required for post-processing . The image forming system according to claim 1, wherein the sheet interval is generated by a timer that outputs an interval signal at a predetermined time interval.

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