JP4218763B2 - Image forming apparatus, post-processing apparatus, and image forming system including these - Google Patents

Description

  The present invention relates to an image forming apparatus such as a printer, a copier, a facsimile machine, or a multi-function machine that conveys paper and forms an image on the paper, a post-processing apparatus having a staple processing function, and an image forming system including these. In particular, the present invention relates to an image forming apparatus, a post-processing apparatus, and an image forming system including these related to control when stapling is attempted beyond the upper limit number of staple processes.

  In a conventional post-processing apparatus, when a sheet exceeding the stapling number is carried in, it is discharged without being stapled as shown in FIG. For this reason, a jam occurs or the copy processing operation is interrupted.

Therefore, in Patent Document 1 below, as shown in FIG. 16, when the number of sheets carried into the stapling apparatus is counted and the counted value exceeds the number of sheets that can be stapled, for example, the number of sheets that can be stapled. When 30 sheets are set to 30 sheets, if 50 sheets are to be copied, the sheet bundle is discharged to the tray with 31 sheet bundles held in the stack unit 26. In order to discharge the remaining 19 sheets on the same tray, the 19 sheets are similarly stacked and discharged.
Japanese Patent No. 2723987

  However, when the number of sheets is the same, this jam is more likely to occur when the sheet bundle is not bound than when the staple process is performed. For this reason, in order to reduce the jam occurrence rate, the upper limit value of the number of sheets for stapling must be set less than the capacity of the stapling apparatus, and only a stapling apparatus having a low capacity can be used. .

  In view of such problems, the object of the present invention is to further reduce the jam occurrence rate when discharging a sheet bundle from the stack unit of the post-processing device to the tray, or to increase the upper limit number of staple processing. It is an object to provide a possible image forming apparatus, a post-processing apparatus, and an image forming system including these.

In the first aspect of the image forming system according to the present invention,
An image forming apparatus that processes image data in units of pages, forms an image on a sheet by an image forming unit based on the processed image data, and discharges the image;
A post-processing device that holds sheets discharged from the image forming apparatus in a stack unit, binds an end of a sheet bundle carried into the stack unit by a staple processing unit, and discharges the bound sheets to a tray;
In an image forming system comprising:
Storage means for storing the upper limit number of staple processes;
In the job for which the staple processing is selected, the number of pages for image data processing is counted, and if it is determined that the preceding count value, which is the count value, exceeds the upper limit number of staple processing, the stapling processing is not performed and Control means for discharging the held sheet bundle to the tray.

  Here, the “number of processed image data pages” is the number of pages of image data that is calculated or actually processed after being processed or processed, and is the number of original image data read pages + on the original tray. It may be the number of pages of original image data processing such as one page by paper detection, or the number of pages after aggregation processing or the like.

In a second aspect of the image forming system according to the present invention, in the first aspect,
The storage means further stores a set number of sheets less than the upper limit number of staple processing,
The control means further counts the number of sheets carried into the stack unit, and when it is determined that the preceding count value exceeds the staple processing upper limit number,
(A) If the post-stage count value, which is the stack section carry-in paper sheet count value, exceeds the set number of sheets, the sheet held in the stack section is discharged to the tray;
(B) If the subsequent-stage count value does not exceed the set number, the sheet held in the stack unit is discharged to the tray after the subsequent-stage count value reaches the set number.

  According to the configuration of the first aspect, the control means counts the number of image data processing pages in the job for which the staple processing is selected, and determines that the preceding count value which is the count value exceeds the upper limit number of staple processing. In this case, since the sheet bundle held in the stack unit without the staple process is discharged to the tray, the number of sheet bundles discharged from the stack part without the staple process becomes less than the upper limit number of staple processes, It is possible to reduce the jam occurrence rate when discharging a bundle of sheets from the stack unit to the tray, or to increase the upper limit number of staple processing than before.

  According to the configuration of the second aspect, when the control unit counts the number of sheets carried into the stack unit and determines that the preceding count value exceeds the staple processing upper limit sheet number, If the count value does not exceed the set number, the sheet held in the stack is discharged to the tray after the subsequent count value reaches the set number. The sheet bundle can be efficiently discharged to the tray.

  Other objects, configurations and effects of the present invention will become apparent from the following description.

  FIG. 1 is a schematic configuration diagram of an image forming system according to Embodiment 1 of the present invention.

  In this system, a post-processing device 20 is connected to the paper discharge side of the image forming apparatus 10.

  In the image forming apparatus 10, data set by operating the operation / display unit 11 is stored in the storage unit 13 via the image formation control unit 12. This setting includes paper size, type and feed direction, document density, frame erasing, binding margin, 4-in-1 aggregation processing, and the like, and it is necessary to perform image processing according to the setting. The time required for image processing depends on this setting. The image formation control unit 12 includes a processor, and a storage unit 13 coupled thereto stores a multi-function application program for performing multi-thread processing.

  When an original is placed on the tray 140 of the auto sheet feeder 14 and the start button of the operation / display unit 11 is pressed, if the paper sensor 141 detects the original paper, the auto sheet feeder 14 makes the original one by one. The original image is scanned by the scanner 142 and the read image data is stored in the storage unit 13 via the image formation control unit 12.

  The image formation control unit 12 performs preprocessing such as image noise removal on the data, performs the image processing, and supplies the data to the print engine 15 in units of pages. As a result, an electrostatic latent image is formed on the surface of the photosensitive drum of the print engine 15, and this is developed with toner.

  On the other hand, the paper taken out from the paper supply unit 16 is sent to the registration roller 17 and stopped once, and the paper is conveyed again by the registration roller 17 at the timing when the photosensitive drum of the print engine 15 reaches a predetermined rotation angle. The toner image is transferred to the paper. This sheet is heated and pressurized through the fixing unit 18, and thereby the toner image is fixed on the sheet. The sheet is further discharged through a discharge roller 19 and supplied to the post-processing device 20.

  In the post-processing device 20, when the staple processing is selected, the branching tool 21 fixed to one of the two angular states is set to a state indicated by a solid line, and otherwise, the state indicated by a two-dot chain line To be.

  When the stapling process is not selected, the sheet that has passed through the conveyance roller 221 is discharged onto the tray 230 through the discharge roller 222 without being influenced by the branching tool 21. A sheet sensor 24 that detects the trailing edge of the sheet is disposed between the conveyance rollers 220 and 221, and an output signal thereof is supplied to the post-processing control unit 25.

  When the stapling process is selected, the paper discharged from the paper discharge roller 19 is transported by the transport rollers 220 and 221, guided downward by the branching tool 21, and supplied to the stack unit 26. .

  The stack unit 26 includes a sheet bundle conveying device 260 in which a belt is stretched between two rollers, and a stopper 261 for holding the lower end portion of the sheet bundle is attached to the belt. The sheet bundle held in the stack unit 26 is bound by the staple processing device 27 at the lower end thereof.

  Here, the storage unit 28 stores in advance a staple processing upper limit number NS0 and a set number NS1 corresponding to the type and size of the paper. The set number NS1 is a value that is assumed to cause no jamming when the sheet bundle is discharged from the stack unit 26 to the tray 231 without performing the stapling process, and is smaller than the maximum staple processing number NS0. is there. For example, when the upper limit number NS0 of staple processing for plain paper B4 size is 30, the set number NS1 is 20, and when the upper limit number NS0 of staple processing for plain paper A4 size is 50, the set number NS1 is set. Is 30 sheets. The set number NS1 also depends on the angle and conveyance speed of the sheet bundle conveyance device 260.

  In this embodiment, the staple processing upper limit sheet number NS0 is used in the image forming control unit 12, but the value of the staple processing upper limit sheet number NS0 differs depending on the type of the post-processing apparatus 20 that can be combined with the image forming apparatus 10. The upper limit number NS0 of staple processes is stored in 28 nonvolatile storage areas (ROM, hard disk or the like). This staple processing upper limit number NS0 is volatilized in the storage unit 13 from the storage unit 28 via the post-processing control unit 25 and the image formation control unit 12 in the initialization process when the image forming apparatus 10 and the operation / display unit 11 are turned on. Stored in a random storage area (RAM).

  If there is one type of post-processing apparatus 20 that can be combined with the image forming apparatus 10 or if the type of post-processing apparatus 20 that can be combined with the image forming apparatus 10 is determined in advance, the storage unit 13. The non-volatile storage area may store the staple processing upper limit number NS0.

  The tray 231 is lowered by the tray lifting and lowering device 29 after discharging the sheet bundle according to the type and number of sheets, that is, according to the thickness of the sheet bundle.

  Next, a copy process performed by the image forming control unit 12 when the auto sheet feeder 14 is used and the staple process is selected will be described with reference to FIG. FIG. 2 is a flowchart showing this processing. This process is started by pressing the start button of the operation / display unit 11. In the following, the step identification codes in the figure are shown in parentheses.

  (S0) The initial value 0 is substituted into the document number counter N.

  (S1) If the paper sensor 141 detects a document, the process proceeds to step S2, and if not, the process proceeds to step S9.

  (S2) If the image forming number counter NX is equal to the staple processing upper limit number NS0, the process proceeds to step S3. Otherwise, the process proceeds to step S4. In a normal case, the image formation number counter NX is equal to the document number counter N. However, for example, in the 4-in-1 aggregation process, NX = [(N−1) / 4] +1. Here, [] is an operator that rounds down the decimal point to the result of the mathematical expression in it to make it an integer. In this embodiment, when NX = NS0, it is determined that there is a document in step S1, and therefore it is determined that NX> NS0.

  (S3) A sheet bundle discharge command is supplied to the post-processing control unit 25. However, when an image is being formed by the print engine 15 or a sheet on which an image is formed is being conveyed, a sheet bundle discharge command is supplied to the post-processing control unit 25 after the sheet is discharged from the image forming apparatus 10. The post-processing control unit 25 sets the paper discharge flag F in the storage unit 28 in response to the interrupt processing. Image formation by the print engine 15 is resumed after the sheet bundle discharge completion signal from the post-processing control unit 25 becomes active.

  The sheet bundle discharge command may be immediately supplied to the post-processing control unit 25, and the sheet bundle discharge command may be regarded as valid after a predetermined time has elapsed on the post-processing device 20 side.

  (S4) The auto sheet feeder 14 is driven to feed one document, and the scanner 142 scans the image. The image data from the scanner 142 is temporarily stored in the storage unit 28.

  If N = 1, in order to perform the processes in steps S6 and S7 in parallel with other processes, a thread for the processes in steps S6 and S7 is generated and activated.

  (S5) Increment N by 1 and return to step S1.

  (S6) The above-described image processing is performed on the image data stored in the storage unit 28 in step S4 in units of pages, and the processed image data is stored in the storage unit 13.

  When the image processing for the first page is completed, a thread for the processing in steps S8 and S9 is generated and activated in order to perform the processing in steps S8 and S9 in parallel with other processing.

  (S7) If there is unprocessed page data, the process returns to step S6; otherwise, the threads of steps S6 and S7 are terminated.

  (S8) One page of processed image data stored in the storage unit 13 is supplied to the print engine 15.

  (S9) If there is unsupplied page data, the process returns to step S8; otherwise, the threads of steps S8 and S9 are terminated.

  (SA) The value of the image formation number counter NX is supplied to the post-processing control unit 25. In response to the interrupt processing, the post-processing control unit 25 substitutes the value of NX for the total number of image formations Nm in the storage unit 28.

  When the staple processing is selected, the image formation control unit 12 supplies a start command to the post-processing control unit 25 when the processing of step S7 is completed for the first page. In response to this, the post-processing control unit 25 starts the processing shown in FIG.

  (S10) Since the total number Nm of image formations in one copy job is unknown, an arbitrary value Nmax, for example, 1000 that is equal to or greater than the number of image formations is substituted for the total number of image formations Nm. This total number Nm of formed images is later updated in step S9.

  (S11) The initial value 0 is substituted into the paper stack number counter i.

  (S12) Wait until the paper sensor 24 detects the trailing edge of the paper.

  (S13) Increment i by 1.

  (S14) If i = Nm, the process proceeds to step S19. Otherwise, the process proceeds to step S15.

  (S15) If i = NS1, the process proceeds to step S16; otherwise, the process returns to step S12.

  (S16) If the paper discharge flag F is set, the process proceeds to step S17, and if not, the process returns to step S12.

  (S17) After the set time elapses, the sheet bundle conveying device 260 is driven to raise the sheet bundle and eject it to the tray 231, and the tray lifting device 29 is further driven to lower the tray 231 according to the thickness. Here, the set time is a time sufficient for reliably holding the paper carried in from the image forming apparatus 10 in the stack unit 26.

  (S18) Substitute the remaining number (Nm-i) into Nm, and return to step S11.

  (S19) If the paper discharge flag F is set, the process proceeds to step S21; otherwise, the process proceeds to step S20.

  (S20) After the set time has elapsed, the sheet bundle held in the stack unit 26 is bound by the staple processing device 27. Here, the set time is a time sufficient for the sheets to be reliably held in the stack unit 26 after the sheet trailing edge is detected by the sheet sensor 24.

  (S21) The sheet bundle conveying device 260 is driven to raise the sheet bundle and discharge it to the tray 231. Further, the tray lifting device 29 is driven to lower the tray 231 according to the thickness.

  4A to 4D are explanatory diagrams of specific examples of the processing as described above when the staple processing is selected. 4 (A) and 4 (B) both show a case where Nm ≦ NS0 and the staple process is executed, and FIGS. 4 (C) and 4 (D) both show Nm> NS0, The case where the stapling process is not executed is shown.

  FIG. 4A shows a case where Nm <NS1, and processing is performed in the following sequence in FIG.

(1) Execute S10 and S11 (2) Execute S12 to S15 repeatedly (Nm-1) times (3) Execute S12 to S14 and S19 to S21 FIG. 4B shows a case where NS1 <Nm <NS0. In FIG. 3, processing is performed in the following sequence.

(1) Execute S10 and S11 (2) Repeat S12 to S15 (NS1-1) times (3) Execute S12 to S16 for i = NS1 to (Nm-1) (4) S12 to S14, S19 to FIG. 4C shows a case where NS0 <Nm <2NS1 and the image forming apparatus 10 determines that Nm> NS0 before stacking NS1 sheets in the stack unit 26. In FIG. It is processed in such a sequence.

(1) Execute S10 and S11 (2) Repeat S12 to S15 (NS1-1) times (3) Execute S12 to S18 for i = NS1: Eject NS1 sheet bundle without stapling (4) S12 To S15 are repeatedly executed (Nm-NS1) times (5) S12 to S14, S19, and S21 are executed for i = Nm: the remaining sheet bundle of NS1 or less is discharged without stapling. FIG. 5C shows NS0 <Nm <2NS1 and a case where Nm> NS0 is determined in the image forming apparatus 10 in a state where N0 sheets (NS1 <N0 <NS0) are stacked in the stack unit 26, and the following sequence is shown in FIG. Is processed.

(1) Execute S10 and S11 (2) Execute S12 to S15 repeatedly (NS1-1) times (3) Execute S12 to S16 for i = NS1 to (N0-1) (4) Execute S12 to S18 i = Execute for N0: discharge N0 sheet bundle without stapling (5) Execute S11 (6) Repeat S12 to S15 (Nm-N0) times (7) Execute S12 to S14, S19, S21 for i = Nm Execution: Ejecting the remaining NS1 or less sheet bundle without stapling As described above, according to the first embodiment, the image forming apparatus 10 reads the upper limit number NS0 of the staple processing, and the sheet sensor 141 reads the next. When the document has been detected, that is, when it is determined that the image data processing page number count value exceeds the staple processing upper limit number NS0, A sheet bundle discharge command is supplied from the image forming control unit 12 to the post-processing control unit 25. In response to this, the post-processing control unit 25 discharges the sheet bundle held in the stack unit 26 to the tray 231 without stapling. Therefore, the number of sheets in the sheet bundle is (NS0-1) or less. Therefore, it is possible to reduce the jam occurrence rate at the time of discharging the sheet bundle from the stack unit 26 to the tray, which contributes to improving the reliability of the image forming system. In addition, this effect makes it possible to increase the upper limit number of staple processing than before.

  Further, since the auto sheet feeder 14 can feed at a high speed or / and the image processing is short, the post-processing control unit 25 can supply a sheet bundle discharge command from the image forming control unit 12 to the post-processing control unit 25. If the counted number of carried-in sheets is less than the set number NS1, the sheet bundle held in the stack unit 26 is discharged to the tray 231 without stapling after the count value reaches the set number NS1. Thus, the sheet bundle can be efficiently discharged to the tray 231 with almost no jamming.

  The present invention includes various modifications in addition to the above.

  For example, in FIG. 2, the counting of the counter in step S5 and the determination position in step S2 are arbitrary, and these may be arranged in the loop of steps S6 and S7 or in the loop of steps S8 and S9. However, when counting the number N of pages after aggregation processing such as 4 in 1, N is used instead of the above-described NX.

  Further, since the image formation control unit 12 and the post-processing control unit 25 are coupled so as to be able to transmit information to each other, the staple processing upper limit number NS0 and the set number NS1 are stored in one of the storage unit 28 and the storage unit 13. Just do it. Further, the post-processing device 20 may be controlled by the image forming control unit 12 without including the post-processing control unit 25 and the storage unit 28. Furthermore, it goes without saying that the image forming apparatus 10 and the post-processing apparatus 20 may be integrally configured.

  Furthermore, although the case where the present invention is applied to the copy function of the image forming apparatus has been described in the above embodiment, the present invention can also be applied to a print or facsimile function.

  Further, “substantially” in claim 3 includes a case where the same result is obtained by repeating the same processing without clearing the count value to zero.

1 is a schematic configuration diagram of an image forming system according to Embodiment 1 of the present invention. 6 is a flowchart illustrating a copy process performed by an image formation control unit when an auto sheet feeder is used and staple processing is selected. It is a flowchart which shows the process by the post-processing control part started in response to the start command from an image formation control part. (A) to (D) are explanatory diagrams of specific examples of the processing in FIGS. 2 and 3, and (A) and (B) each show a case where stapling processing is executed, and (C) and (D) ) Indicates a case where the stapling process is not executed. It is explanatory drawing of the problem of a prior art.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Image forming apparatus 11 Operation / display part 12 Image formation control part 13, 28 Storage part 14 Auto sheet feeder 140, 230, 231 Tray 141, 24 Paper sensor 142 Scanner 15 Print engine 16 Paper feed part 17 Registration roller 18 Fixing device 19 , 222 Paper discharge roller 20 Post-processing device 21 Branch tool 220, 221 Conveying roller 25 Post-processing control unit 26 Stack unit 260 Sheet bundle conveying device 261 Stopper 27 Staple processing device 29 Tray lifting device NS0 Staple processing upper limit number NS1 Set number of sheets Nm Total Number of images formed

Claims (5)

An image forming apparatus that processes image data in units of pages, forms an image on a sheet by an image forming unit based on the processed image data, and discharges the image;
A post-processing device that holds sheets discharged from the image forming apparatus in a stack unit, binds an end of a sheet bundle carried into the stack unit by a staple processing unit, and discharges the bound sheets to a tray;
In an image forming system comprising:
Storage means for storing the upper limit number of staple processes;
In the job for which the staple processing is selected, the number of pages for image data processing is counted, and if it is determined that the preceding count value, which is the count value, exceeds the upper limit number of staple processing, the stapling processing is not performed and Control means for discharging the held sheet bundle to the tray;
The image forming system is characterized in that the number of sheet bundles discharged from the stack unit without the staple process is less than the upper limit number of staple processes. The storage means further stores a set number of sheets less than the upper limit number of staple processing,
The control means further counts the number of sheets carried into the stack unit, and when it is determined that the preceding count value exceeds the staple processing upper limit number,
(A) If the post-stage count value, which is the stack section carry-in paper sheet count value, exceeds the set number of sheets, the sheet held in the stack section is discharged to the tray;
(B) If the succeeding-stage count value does not exceed the set number of sheets, the process waits until the succeeding-stage count value reaches the set number of sheets, and discharges the paper held in the stack unit to the tray.
The image forming system according to claim 1. If there is a sheet to be carried into the stack section after the process (b), the control means
In effect, the count value is cleared to zero and the process of (b) is repeated zero or more times.
In the process of (b), when the paper carry-in to the stack unit is completed before the subsequent count value reaches the set number, the paper held in the stack unit is discharged to the tray.
The image forming system according to claim 2. In an image forming apparatus that processes image data on a page-by-page basis, and forms and discharges an image on a sheet by image forming means based on the processed image data.
When the number of pages for image data processing is counted for a job for which stapling processing is selected, and it is determined that the count exceeds the maximum number of staple processing sheets, the end of a plurality of sheet bundles held in the stack unit Control means for supplying a sheet bundle discharge command for discharging the sheet bundle from the stack unit to the tray without stapling processing to the post-processing device
The image forming apparatus is characterized in that the number of sheet bundles discharged from the stack unit without the stapling process is less than the upper limit number of stapling processes. Used in an image forming apparatus that processes image data page by page, and forms and discharges an image on a sheet by an image forming unit based on the processed image data. The sheet discharged from the image forming apparatus is held in a stack unit. In the post-processing apparatus for binding the end of the sheet bundle carried into the stack unit by the staple processing unit and discharging the bound sheet to the tray,
Storage means for storing the upper limit number of staple processes and a set number of sheets smaller than the upper limit number of staple processes;
Control means;
The control means counts the number of sheets carried into the stack unit, and responds to a sheet bundle discharge command from the image forming apparatus,
(A) If the post-stage count value, which is the stack section carry-in paper sheet count value, exceeds the set number of sheets, the sheet held in the stack section is discharged to the tray;
(B) If the succeeding-stage count value does not exceed the set number of sheets, the process waits for the succeeding-stage count value to reach the set number of sheets, and discharges the paper held in the stack unit to the tray.
The image forming apparatus receives the staple processing upper limit number from the storage unit, counts the number of image data processing pages in the job for which the staple processing is selected, and determines that the count value exceeds the staple processing upper limit number. In this case, the paper bundle discharge command is output.
A post-processing device.

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