JP6003159B2 - Image forming system - Google Patents

Description

  The present invention relates to an image forming system.

  Conventionally, in order to increase the productivity of double-sided printing, a plurality of image forming apparatuses are connected in series along the paper conveyance direction, the surface is printed by an upstream image forming apparatus (upstream machine), and downstream image formation is performed. An image forming system having a series tandem configuration in which a back surface is printed by an apparatus (downstream machine) is known.

  For example, if an abnormality occurs while recording images by connecting a plurality of copying apparatuses in series, the recording operation is immediately stopped for the downstream apparatus downstream from the apparatus where the abnormality has occurred. A technique has been proposed in which the process continues without being performed, and is stopped after the image recording of all the recording sheets carried in before the occurrence of the abnormality is completed (see Patent Document 1).

  In general, in the image forming apparatus, when a factor for stopping paper feeding (hereinafter, referred to as a “stopping factor”) occurs during printing, such as no paper or out of toner, the final paper of the paper managed at that timing is determined. Control is made to stop the printing operation after the paper is discharged.

JP 59-121066

  However, when a stop factor occurs in an image forming system with a serial tandem configuration, when each of the upstream machine and the downstream machine performs such control, the downstream machine manages only the paper in the downstream machine. When the final paper in the downstream machine is discharged when the stop factor is generated, the printing operation is stopped, and the paper discharged from the upstream machine enters the downstream machine, causing a problem of jamming.

  The present invention has been made in view of the above-described problems in the prior art, and in an image forming system having a series tandem configuration, a jam caused by a deviation in the determination of the stop timing of the upstream machine and the downstream machine when a stop factor occurs. It is an object to prevent the occurrence of this.

In order to solve the above-described problem, the invention described in claim 1 is an image forming system having a tandem configuration in which a plurality of image forming apparatuses are connected in series along a sheet conveyance direction, and among the plurality of image forming apparatuses. The upstream image forming apparatus in the paper transport direction determines a final sheet according to the stop factor when a stop factor occurs in the upstream image forming apparatus, and determines the final sheet as the upstream image. After discharging from the forming apparatus, the printing operation of the upstream image forming apparatus is stopped, and information indicating the stop factor and the final sheet is transmitted to the image forming apparatus downstream of the upstream image forming apparatus. It includes an upstream-side control unit, the image forming apparatus of the downstream is provided a downstream job control unit that manages the job, and a downstream-side printer control unit for controlling the image formation and conveyance of the sheet, and Serial downstream printer control unit, based on the information indicating the final paper received from the upstream controller, controls the timing of transmitting the stop factor received from the upstream control unit to the downstream job control unit The downstream job control unit determines a final sheet in the downstream image forming apparatus based on the stop factor received from the downstream printer control unit , information indicating the final sheet, and the downstream side A downstream stop instruction for stopping the printing operation of the image forming apparatus is transmitted to the downstream printer control unit, and the downstream printer control unit indicates information indicating the final sheet received from the downstream job control unit and based on said downstream stop instruction, stops the printing operation of the downstream side of the image forming apparatus the final paper after discharged from the image forming apparatus of the downstream To Ru.

According to a second aspect of the present invention, in the image forming system according to the first aspect, the upstream control unit includes an upstream job control unit that manages jobs, and an upstream printer that controls image formation and paper conveyance. and a control unit, and if the cause of termination has occurred in the image forming apparatus of the upstream side does not jam, the upstream printers control section transmits the stop factor to the upstream Gawaji job control unit , transmits the stop factor to the downstream printers control unit, the upstream Gawaji job control unit determines the final paper in response to the stop factor received from the upstream printers control unit, the final transmits upstream stop instruction for stopping the printing operation of the image forming apparatus information and the upstream shows the paper to the upstream printers control unit, the upstream printers control unit, the upstream Gawaji ® Based on the information and the upstream stop instruction indicating the final paper received from the control unit, to stop the printing operation of the upstream side of the image forming apparatus the final paper after discharged from the image forming apparatus of the upstream , and it transmits information indicating the last sheet to the downstream printers control unit, the downstream printers control unit, based on the information indicating the final paper received from the upstream printers control unit, the downstream transmitting the stop cause which the last sheet in the image forming apparatus side is at a timing sheet passing received from the upstream printers control unit to the downstream Gawaji job controller.

According to a third aspect of the present invention, in the image forming system according to the first aspect, the upstream control unit includes an upstream job control unit that manages jobs, and an upstream printer that controls image formation and paper conveyance. and a control unit, and when a jam occurs as the stop factor in the image forming apparatus of the upstream, the upstream printers control unit transmits the stop factor to the upstream Gawaji job control unit sends said stop cause the downstream printers control unit determines the final paper in response to the occurrence position of the jam, the upstream side of the image forming the final paper after discharged from the image forming apparatus of the upstream stops the printing operation of the apparatus, transmits the information indicating the last sheet to the downstream printers control unit, the downstream printers control unit received from the upstream printers controller the Based on the information indicating the final paper, the cause of termination is received from the upstream printers control unit in the final paper to the image forming apparatus of the downstream side is passing feed timing to the downstream Gawaji job control unit Send .

According to a fourth aspect of the present invention, in the image forming system having a tandem configuration in which a plurality of image forming apparatuses are connected in series along the sheet conveying direction, the downstream of the plurality of image forming apparatuses in the sheet conveying direction. The image forming apparatus includes a downstream job control unit that manages jobs, and a downstream printer control unit that controls image formation and paper conveyance, and the downstream printer control unit includes the downstream image forming apparatus. When a stop factor other than a jam occurs, the stop factor is transmitted to an image forming device upstream of the downstream image forming device, and the upstream image forming device transmits the downstream printer control unit. determining the final paper in response to the stop factor received from, stops the printing operation of the upstream side of the image forming apparatus the final paper after discharged from the image forming apparatus of the upstream Both provided upstream control unit that transmits information indicating the last sheet to the image forming apparatus of the downstream, the downstream printer control unit, based on the information indicating the final paper received from the upstream controller And controlling the timing of transmitting the stop factor to the downstream job control unit, and the downstream job control unit forms the downstream image formation based on the stop factor received from the downstream printer control unit. Determines the final sheet in the apparatus, transmits information indicating the final sheet and a downstream stop instruction for stopping the printing operation of the downstream image forming apparatus to the downstream printer control unit, and controls the downstream printer control parts, based on the information and the downstream stop instruction indicating the final paper received from the downstream job control unit, the final paper or the image forming apparatus of the downstream Wherein stopping the printing operation of the downstream side of the image forming apparatus after discharge.

The invention of claim 5 is the image forming system according to claim 4, before Symbol upstream controller, an upstream-side job control unit for managing jobs, upstream to control the image formation and conveyance of the sheet comprising a printer control unit, wherein the downstream printers control unit transmits the stop factor to the upstream printers control unit, the upstream printers control unit receives from the downstream printers controller transmitting the stop factor that the upstream Gawaji job control unit, the upstream Gawaji job control unit determines the final paper in response to the stop factor received from the upstream printers control unit, the transmits upstream stop instruction for stopping the printing operation of the image forming apparatus information and the upstream shows the last sheet to the upstream side printers control unit, the upstream printers control unit, the upstream Gawaji Job control Based on the information and the upstream stop instruction indicating the final paper received from, stops the printing operation of the upstream side of the image forming apparatus the final paper after discharged from the image forming apparatus of the upstream, the It transmits information indicating the last sheet to the downstream printers control unit, the downstream printers control unit, based on the information indicating the final paper received from the upstream printers control unit, of the downstream the final paper to the image forming apparatus transmits the stop factor at a timing sheet passing on the downstream Gawaji job controller.

  According to the present invention, in an image forming system having a serial tandem configuration, it is possible to prevent the occurrence of a jam due to a shift in the determination of the stop timing of the upstream machine and the downstream machine when a stop factor occurs.

1 is an external configuration diagram of an image forming system in an embodiment of the present invention. It is a block diagram which shows the structure of an upstream machine and a downstream machine. 1 is a schematic block diagram of an image forming system. FIG. 5 is a diagram for explaining a printing operation in the image forming system. 6 is a flowchart illustrating processing of a printer control unit of an upstream machine when a stop factor occurs in the upstream machine. 6 is a flowchart illustrating processing of a printer control unit of a downstream machine when a stop factor occurs in the upstream machine. 6 is a flowchart illustrating processing of a printer control unit of a downstream machine when a stop factor occurs in the downstream machine. 6 is a flowchart illustrating processing of a printer control unit of an upstream machine when a stop factor occurs in the downstream machine. It is a flowchart which shows the process of the job control part of an upstream machine, and the job control part of a downstream machine. FIG. 6 is a diagram illustrating a situation where no paper has occurred in an upstream machine during printing. FIG. 10 is a diagram for explaining a print stop control process when there is no paper in the upstream machine. FIG. 6 is a diagram illustrating a situation where toner has run out in a downstream machine during printing. FIG. 10 is a diagram for explaining a print stop control process when toner runs out in a downstream machine.

  Embodiments of an image forming system according to the present invention will be described below with reference to the drawings.

[Configuration of image forming system]
FIG. 1 is an external configuration diagram of an image forming system 100 in the present embodiment.
As shown in FIG. 1, an image forming system 100 includes a paper feeding unit 10, an upstream image forming apparatus (hereinafter referred to as an upstream machine) 20, and a downstream image forming apparatus (hereinafter referred to as an upstream apparatus) along the paper conveyance direction. This is a tandem configuration in which a downstream machine 30) and an FNS (post-processing unit) 40 are connected in series. The upstream machine 20 and the downstream machine 30 are developed as a single image forming apparatus, but the upstream machine 20 and the downstream machine 30 are connected, and each image forming apparatus forms an image on one side of a sheet. Thus, it is possible to perform double-sided printing at high speed. Note that the image forming system 100 may be configured not to include the paper feeding unit 10 and the FNS 40.

  The paper feed unit 10 is called a PFU (Paper Feed Unit), and includes a paper feed means including a plurality of paper feed trays, paper feed rollers, separation rollers, paper feed / separation rubbers, feed rollers, and the like. Prepare. Each paper feed tray stores paper for each paper type (paper type, basis weight, paper size, etc.), and the paper is transported from the top of the paper one by one to the upstream machine 20 by the paper feeding means. The

The upstream machine 20 forms an image on a sheet based on print data and print setting data (print job) in a page description language format such as a PDL (Page Description Language) format or a Tiff format received from an external device or the like. An image is formed on a sheet based on the image data read from.
The downstream machine 30 forms an image on a sheet in the same manner as the upstream machine 20.

  The FNS 40 includes various post-processing units such as a sorting unit, a stapling unit, a punching unit, and a folding unit, and a paper discharge tray. The FNS 40 performs various post-processing on the paper conveyed from the downstream machine 30 and performs post-processing. The discharged paper is discharged to the paper output tray.

FIG. 2 is a block diagram illustrating configurations of the upstream machine 20 and the downstream machine 30.
The upstream machine 20 includes a job control unit 21, a printer control unit 22, an image processing unit 23, an image forming unit 24, a paper transport unit 25, a paper feed tray control unit 26, an operation unit 51, a controller 52, and a DF (Document Feeder) control. Unit 53, scanner control unit 54, PFU (Paper Feed Unit) control unit 11 and the like.

The job control unit 21 receives the print job received by the controller 52 and manages image data and jobs (including job start and stop). The job control unit 21 includes a CPU (Central Processing Unit), a RAM (Random Access Memory), a ROM (Read Only Memory), and the like. The CPU performs various processes in cooperation with a job control program stored in the ROM. Execute.
The job control unit 21 and the printer control unit 22 are connected via a serial communication line so that data communication is possible.
The job control unit 21 of the upstream machine 20 and the job control unit 31 of the downstream machine 30 are connected to be able to perform data communication via a LAN (Local Area Network), and mainly transmit / receive image data.

The printer control unit 22 controls image formation and paper conveyance in the upstream machine 20. The printer control unit 22 includes a CPU, a RAM, a ROM, and the like, and the CPU executes various processes in cooperation with a printer control program stored in the ROM. Specifically, the printer control unit 22 includes an image forming unit 24, a fixing unit 28 (see FIG. 4), a paper transport unit 25, a paper feed tray control unit 26, a DF control unit 53, a scanner control unit 54, and a PFU control unit. 11 etc. are controlled.
The printer control unit 22 of the upstream machine 20 and the printer control unit 32 of the downstream machine 30 are connected via a serial communication line so that data communication is possible, and mainly transmits and receives control information (paper position, main body state, etc.).

  The image processing unit 23 performs image processing on image data that is an object of image formation in the upstream machine 20.

The image forming unit 24 includes a photosensitive drum, a charging unit that charges the photosensitive drum, an exposure unit that exposes and scans the surface of the photosensitive drum based on image data, a developing unit that attaches toner to the photosensitive drum, and a photosensitive drum The image forming apparatus includes a transfer unit that transfers the toner image formed on the paper to a sheet.
The paper transport unit 25 includes a transport roller, a registration unit 27 (see FIG. 4), a reversing unit 29 (see FIG. 4), and the like, and transports the paper.
The paper feed tray control unit 26 controls the supply of paper from the paper feed tray in the upstream machine 20 to the image forming unit 24.

The operation unit 51 includes an LCD (Liquid Crystal Display), a touch panel provided so as to cover the LCD, various switches and buttons, a numeric keypad, a group of operation keys, and the like. The operation unit 51 receives an instruction from the user, outputs an operation signal to the job control unit 21, and inputs various operation instructions and setting information according to a display signal input from the job control unit 21. Displays the setting screen and various processing results.
The controller 52 manages and controls data to be printed (print data and print setting data) received from the external device.

The DF control unit 53 controls document conveyance in the document feeding unit.
The scanner control unit 54 controls a document reading operation in the scanner unit.

  The PFU control unit 11 controls the supply of paper from the paper feed tray in the paper feed unit 10 to the image forming unit 24. The paper feed unit 10 is a unit managed by the upstream machine 20.

  The downstream machine 30 includes a job control unit 31, a printer control unit 32, an image processing unit 33, an image forming unit 34, a paper transport unit 35, a paper feed tray control unit 36, a post-processing control unit 41, and the like.

The job control unit 31 receives the print job transmitted from the job control unit 21 and manages image data and jobs (including job start and stop). The job control unit 31 includes a CPU, a RAM, a ROM, and the like, and the CPU executes various processes in cooperation with a job control program stored in the ROM.
The job control unit 31 and the printer control unit 32 are connected via a serial communication line so that data communication is possible.

  The printer control unit 32 controls image formation and paper conveyance in the downstream machine 30. The printer control unit 32 includes a CPU, a RAM, a ROM, and the like, and the CPU executes various processes in cooperation with a printer control program stored in the ROM. Specifically, the printer control unit 32 controls the image forming unit 34, the fixing unit 38 (see FIG. 4), the paper transport unit 35, the paper feed tray control unit 36, the post-processing control unit 41, and the like.

  The image processing unit 33 performs image processing on image data that is a target of image formation in the downstream device 30.

The image forming unit 34 includes a photosensitive drum, a charging unit that charges the photosensitive drum, an exposure unit that exposes and scans the surface of the photosensitive drum based on image data, a developing unit that attaches toner to the photosensitive drum, and a photosensitive drum The image forming apparatus includes a transfer unit that transfers the toner image formed on the paper to a sheet.
The paper transport unit 35 includes a transport roller, a registration unit 37 (see FIG. 4), a reversing unit 39 (see FIG. 4), and the like, and transports the paper.
The paper feed tray control unit 36 controls the supply of paper from the paper feed tray in the downstream machine 30 to the image forming unit 34. Note that when image formation is performed using paper supplied from a paper feed tray in the downstream machine 30, the functions of the image forming unit 24 and the paper transport unit 25 of the upstream machine 20 are stopped.

  The post-processing control unit 41 controls a post-processing operation in the FNS 40. The FNS 40 is a unit managed by the downstream machine 30.

  In the present embodiment, an event that causes image formation in the upstream machine 20 or the downstream machine 30 and conveyance of the paper in the image forming system 100 to be stopped is referred to as a stop factor. As the stop factors, for example, there is no paper, the toner runs out, the staple staple of the FNS 40 runs out, a jam, and the like.

  Each paper feed tray is provided with a paper detection sensor that detects the presence or absence of paper. The printer control unit 22 of the upstream machine 20 and the printer control unit 32 of the downstream machine 30 are based on the output signal of the paper detection sensor corresponding to the paper feed tray that is feeding in the own device or a unit managed by the own device. Detect occurrence of paper out. The occurrence of paper out may be detected by other methods.

  The upstream machine 20 and the downstream machine 30 are provided with density detection sensors that detect the density of images formed by the image forming units 24 and 34, respectively. The printer control unit 22 of the upstream machine 20 and the printer control unit 32 of the downstream machine 30 detect that the toner amount of the own apparatus has become a predetermined value or less based on the output signal of the density detection sensor. The occurrence of toner out may be detected by other methods.

  The staple unit of the FNS 40 is provided with a remaining amount detection sensor that detects the remaining amount of staples. Based on the output signal of the remaining amount detection sensor received via the post-processing control unit 41, the printer control unit 32 of the downstream machine 30 detects that the number of staples has become a predetermined number or less. A staple breakage in the FNS 40 is notified before the needle is completely lost.

A plurality of paper detection sensors that detect the presence or absence of paper are provided in the paper conveyance path of the image forming system 100. The printer control unit 22 of the upstream machine 20 and the printer control unit 32 of the downstream machine 30 generate the jam and the position of the jam based on the output signal of the paper detection sensor provided in the own device or a unit managed by the own device. Is detected.
Further, the printer control unit 22 of the upstream machine 20 and the printer control unit 32 of the downstream machine 30 indicate that the paper is discharged from the own apparatus based on the output signal of the paper detection sensor provided at the discharge port of the own apparatus. Is detected. Further, the printer control unit 32 of the downstream machine 30 detects that a sheet has been passed through the downstream machine 30 based on an output signal of a sheet detection sensor provided at the sheet inlet of the downstream machine 30.

When a stop factor occurs in the upstream machine 20, the job control unit 21 or the printer control unit 22 (upstream side control unit) of the upstream machine 20 determines the final sheet according to the stop factor, and uses the final sheet as the upstream machine 20. In addition to stopping the printing operation of the upstream machine 20 after discharging from the printer, information indicating the stop factor and the final paper (hereinafter referred to as final paper information) is transmitted to the downstream machine 30.
The job control unit 31 or the printer control unit 32 (downstream side control unit) of the downstream machine 30 discharges the final paper from the downstream machine 30 based on the stop factor and the final paper information received from the upstream machine 20, and then the downstream machine 30. Stop the printing operation.

Specifically, when a stop factor other than a jam occurs in the upstream machine 20, the printer control unit 22 of the upstream machine 20 transmits the stop factor to the job control unit 21 of the upstream machine 20, and the stop factor is transmitted to the downstream machine. To 30 printer control units 32.
The job control unit 21 of the upstream machine 20 determines the final sheet according to the stop factor received from the printer control unit 22 of the upstream machine 20, and determines the final sheet information and a stop instruction for stopping the printing operation of the upstream machine 20 ( (Upstream stop instruction) is transmitted to the printer control unit 22 of the upstream machine 20.
The printer control unit 22 of the upstream machine 20 stops the printing operation of the upstream machine 20 after discharging the final sheet from the upstream machine 20 based on the final paper information and the stop instruction received from the job control unit 21 of the upstream machine 20. At the same time, the final paper information is transmitted to the printer control unit 32 of the downstream machine 30.
Based on the final paper information received from the printer control unit 22 of the upstream machine 20, the printer control unit 32 of the downstream machine 30 receives the final paper from the printer control unit 22 of the upstream machine 20 at the timing when the final paper is passed through the downstream machine 30. The received stop factor is transmitted to the job control unit 31 of the downstream machine 30.
The job control unit 31 of the downstream machine 30 determines the final sheet according to the stop factor received from the printer control unit 32 of the downstream machine 30, and the stop instruction for stopping the printing operation of the final sheet information and the downstream machine 30 ( The downstream stop instruction) is transmitted to the printer control unit 32 of the downstream machine 30.
The printer control unit 32 of the downstream machine 30 stops the printing operation of the downstream machine 30 after discharging the final paper from the downstream machine 30 based on the final paper information and the stop instruction received from the job control unit 31 of the downstream machine 30. .

On the other hand, when a jam occurs as a stop factor in the upstream machine 20, the printer control unit 22 of the upstream machine 20 transmits the stop factor to the job control unit 21 of the upstream machine 20, and the stop factor is the printer control of the downstream machine 30. Is transmitted to the unit 32, the final paper is determined according to the jam occurrence position, the printing operation of the upstream machine 20 is stopped after the final paper is discharged from the upstream machine 20, and the final paper information is sent to the printer control of the downstream machine 30. It transmits to the part 32.
Based on the final paper information received from the printer control unit 22 of the upstream machine 20, the printer control unit 32 of the downstream machine 30 receives the final paper from the printer control unit 22 of the upstream machine 20 at the timing when the final paper is passed through the downstream machine 30. The received stop factor is transmitted to the job control unit 31 of the downstream machine 30.
The job control unit 31 of the downstream machine 30 determines the final paper according to the stop factor received from the printer control unit 32 of the downstream machine 30, and issues a stop instruction for stopping the final paper information and the printing operation of the downstream machine 30. The data is transmitted to the printer control unit 32 of the downstream machine 30.
The printer control unit 32 of the downstream machine 30 stops the printing operation of the downstream machine 30 after discharging the final paper from the downstream machine 30 based on the final paper information and the stop instruction received from the job control unit 31 of the downstream machine 30. .

When a stop factor other than a jam occurs in the downstream machine 30, the job control unit 31 or the printer control unit 32 (downstream control unit) of the downstream machine 30 transmits the stop factor to the upstream machine 20.
The job control unit 21 or the printer control unit 22 (upstream side control unit) of the upstream machine 20 determines the final paper according to the stop factor received from the downstream machine 30, and after discharging the final paper from the upstream machine 20, the upstream machine 20 print operation is stopped and final paper information is transmitted to the downstream machine 30.
The job control unit 31 or the printer control unit 32 of the downstream machine 30 stops the printing operation of the downstream machine 30 after discharging the final paper from the downstream machine 30 based on the final paper information received from the upstream machine 20.

Specifically, when a stop factor other than a jam occurs in the downstream machine 30, the printer control unit 32 of the downstream machine 30 transmits the stop factor to the printer control unit 22 of the upstream machine 20.
The printer control unit 22 of the upstream machine 20 transmits the stop factor received from the printer control unit 32 of the downstream machine 30 to the job control unit 21 of the upstream machine 20.
The job control unit 21 of the upstream machine 20 determines the final sheet according to the stop factor received from the printer control unit 22 of the upstream machine 20, and determines the final sheet information and a stop instruction for stopping the printing operation of the upstream machine 20 ( (Upstream stop instruction) is transmitted to the printer control unit 22 of the upstream machine 20.
The printer control unit 22 of the upstream machine 20 stops the printing operation of the upstream machine 20 after discharging the final sheet from the upstream machine 20 based on the final paper information and the stop instruction received from the job control unit 21 of the upstream machine 20. At the same time, the final paper information is transmitted to the printer control unit 32 of the downstream machine 30.
Based on the final paper information received from the printer control unit 22 of the upstream machine 20, the printer control unit 32 of the downstream machine 30 determines the stop factor at the timing when the final paper is passed to the downstream machine 30 and performs job control of the downstream machine 30. It transmits to the part 31.
The job control unit 31 of the downstream machine 30 determines the final sheet according to the stop factor received from the printer control unit 32 of the downstream machine 30, and the stop instruction for stopping the printing operation of the final sheet information and the downstream machine 30 ( The downstream stop instruction) is transmitted to the printer control unit 32 of the downstream machine 30.
The printer control unit 32 of the downstream machine 30 stops the printing operation of the downstream machine 30 after discharging the final paper from the downstream machine 30 based on the final paper information and the stop instruction received from the job control unit 31 of the downstream machine 30. Let

On the other hand, when a jam occurs as a stop factor in the downstream machine 30, the printer control unit 32 of the downstream machine 30 transmits the stop factor to the printer control unit 22 of the upstream machine 20, and finally determines according to the jam occurrence position. After determining the paper and discharging the final paper from the downstream machine 30, the printing operation of the downstream machine 30 is stopped.
The printer control unit 22 of the upstream machine 20 transmits the stop factor received from the printer control unit 32 of the downstream machine 30 to the job control unit 21 of the upstream machine 20 and stops the printing operation of the upstream machine 20.

  Note that the job control unit 21 of the upstream machine 20 and the job control unit 31 of the downstream machine 30 store a table (hereinafter referred to as stop timing setting information) in which stop factors are associated with final sheet determination methods. The final sheet according to the stop factor is determined with reference to this table. For example, in the apparatus, the most upstream sheet among the already fed sheets is determined to be the last sheet, or the sheet that becomes a break such as a job break or a set break is determined to be the last sheet.

  In addition, the printer control unit 22 of the upstream machine 20 and the printer control unit 32 of the downstream machine 30 exist on the downstream side of the jam occurrence position when the occurrence of the jam is detected in the own device or a unit managed by the own device. Among the sheets to be printed, the most upstream sheet is determined as the final sheet.

[Overview of print operation]
Next, an outline of the printing operation of the image forming system 100 will be described with reference to FIGS. 3 and 4.
FIG. 3 is a schematic block diagram of the image forming system 100.
FIG. 4 is a diagram for explaining a printing operation in the image forming system 100.

The job control unit 21 of the upstream machine 20 includes a job execution unit 21a and a job division unit 21b. The job control unit 31 of the downstream machine 30 includes a job execution unit 31a.
First, when the job control unit 21 of the upstream machine 20 receives a print job from the controller 52, the job dividing unit 21b divides the print job into an even page job and an odd page job, and executes the even page job as a job of its own device. The odd page job is transmitted to the job execution unit 31 a of the downstream machine 30.

Based on the even page job received from the job dividing unit 21b, the job execution unit 21a of the upstream machine 20 transmits information necessary for image formation to the printer control unit 22 and instructs the job start.
The job execution unit 31a of the downstream machine 30 transmits information necessary for image formation to the printer control unit 32 based on the odd page job received from the job dividing unit 21b, and instructs the start of the job.

  When receiving the job start instruction from the job control unit 21, the printer control unit 22 of the upstream machine 20 feeds paper from the paper feed unit 10 or the paper feed tray in the upstream machine 20, and the registration unit 27 bends the paper. Is corrected, the first image is printed by the image forming unit 24 of the upstream machine 20. Thereafter, the printer control unit 22 fixes the toner on the paper by the fixing unit 28, reverses the paper by the reversing unit 29, and sends the paper to the downstream machine 30.

  The printer control unit 32 of the downstream machine 30 corrects the bending of the paper sent to the downstream machine 30 by the registration unit 37, and then prints an image on the other side by the image forming unit 34 of the downstream machine 30. . Thereafter, the printer control unit 32 fixes the toner on the sheet by the fixing unit 38 and discharges the sheet to the FNS 40.

[Operation of the printer control section of the upstream machine when a stop factor occurs in the upstream machine]
FIG. 5 is a flowchart illustrating processing of the printer control unit 22 of the upstream machine 20 when a stop factor occurs in the upstream machine 20.

  First, after a print is started in the upstream machine 20 (step S1), if a stop factor occurs in the upstream machine 20 (step S2; YES), the printer control unit 22 performs a job control unit 21 of the upstream machine 20. A stop factor is transmitted to (step S3). Note that the absence of paper or jam in the paper supply unit 10 is determined as a stop factor that has occurred in the upstream machine 20.

  Next, the printer control unit 22 transmits a stop factor to the printer control unit 32 of the downstream machine 30 (step S4).

  If the stop factor is not a jam (step S5; NO), the printer control unit 22 performs the print operation after waiting for the final paper information and the stop instruction (final paper discharge) from the job control unit 21 of the upstream machine 20. When an instruction to stop is received (step S6; YES), the final paper information is transmitted to the printer control unit 32 of the downstream device 30 (step S8).

  In step S5, when the stop factor is a jam (step S5; YES), the printer control unit 22 determines the final sheet in the upstream machine 20 (step S7). Specifically, the printer control unit 22 determines that the most upstream sheet among the sheets existing downstream of the jam occurrence position is the final sheet. Then, the printer control unit 22 transmits final paper information to the printer control unit 32 of the downstream machine 30 (step S8).

  After step S8, after the final paper is discharged from the upstream machine 20 (step S9; YES), the printer control unit 22 controls the image forming unit 24, the paper transport unit 25, etc., and the printing operation of the upstream machine 20 is performed. Is stopped (step S10).

[Operation of the printer control section of the downstream machine when a stop factor occurs in the upstream machine]
FIG. 6 is a flowchart illustrating processing of the printer control unit 32 of the downstream machine 30 when a stop factor occurs in the upstream machine 20.

  First, after printing is started in the downstream machine 30 (step S11), when a stop factor and final paper information are received from the printer control unit 22 of the upstream machine 20 (step S12; YES, step S13; YES), Based on the final paper information, the printer control unit 32 determines whether or not the final paper has been passed through the downstream device 30 (step S14).

  When the final sheet is passed through the downstream machine 30 (step S14; YES), the printer control unit 32 transmits a stop factor to the job control unit 31 of the downstream machine 30 (step S15).

  Next, when the final paper information and the stop instruction are received from the job control unit 31 of the downstream machine 30 (step S16; YES), the printer control unit 32 discharges the final paper from the downstream machine 30 (step S17; YES). ), The image forming unit 34, the paper transport unit 35, and the like are controlled to stop the printing operation of the downstream machine 30 (step S18).

[Operation of the printer control unit of the downstream machine when a stop factor occurs in the downstream machine]
FIG. 7 is a flowchart illustrating processing of the printer control unit 32 of the downstream machine 30 when a stop factor occurs in the downstream machine 30.

  First, after printing is started in the downstream machine 30 (step S21), if a stop factor occurs in the downstream machine 30 (step S22; YES), the printer control unit 32 causes the printer control unit 22 of the upstream machine 20 to print. A stop factor is transmitted to (step S23). It should be noted that a shortage or jamming of staples used for post-processing in the FNS 40 is determined as a stop factor that has occurred in the downstream machine 30.

  Here, when the stop factor is not jam (step S24; NO), the printer control unit 32 receives the final paper information from the printer control unit 22 of the upstream machine 20 (step S25; YES), the final paper information. Based on this, it is determined whether or not the final sheet has been passed through the downstream machine 30 (step S26).

  When the final sheet is passed through the downstream machine 30 (step S26; YES), the printer control unit 32 transmits a stop factor to the job control unit 31 of the downstream machine 30 (step S27).

  Next, when the final paper information and the stop instruction are received from the job control unit 31 of the downstream machine 30 (step S28; YES), the printer control unit 32 discharges the final paper from the downstream machine 30 (step S31; YES). ), The image forming section 34, the paper transport section 35, etc. are controlled to stop the printing operation of the downstream machine 30 (step S32).

  In step S24, when the stop factor is a jam (step S24; YES), the printer control unit 32 transmits the stop factor to the job control unit 31 of the downstream machine 30 (step S29), and the printer 30 The final sheet is determined (step S30). Specifically, the printer control unit 32 determines that the most upstream sheet among the sheets existing downstream of the jam occurrence position is the final sheet. Then, after the final sheet is discharged from the downstream machine 30 (step S31; YES), the printer control unit 32 controls the image forming unit 34, the paper transport unit 35, and the like to stop the printing operation of the downstream machine 30. (Step S32).

[Operation of the printer control section of the upstream machine when a stoppage occurs in the downstream machine]
FIG. 8 is a flowchart illustrating processing of the printer control unit 22 of the upstream machine 20 when a stop factor occurs in the downstream machine 30.

  First, after printing is started in the upstream device 20 (step S41), when a stop factor is received from the printer control unit 32 of the downstream device 30 (step S42; YES), the printer control unit 22 determines that the upstream device 20 A stop factor is transmitted to the job control unit 21 (step S43).

  If the stop factor is not jam (step S44; NO), the printer control unit 22 receives the final paper information and the stop instruction from the job control unit 21 of the upstream machine 20 (step S45; YES), and downstream. The final paper information is transmitted to the printer control unit 32 of the machine 30 (step S46).

  Next, after the final paper is discharged from the upstream machine 20 (step S47; YES), the printer control unit 22 controls the image forming unit 24, the paper transport unit 25, and the like to stop the printing operation of the upstream machine 20. (Step S48).

  In step S44, when the stop factor is a jam (step S44; YES), the printer control unit 22 controls the image forming unit 24, the paper transport unit 25, and the like to stop the printing operation of the upstream machine 20. (Step S48).

[Operation of Job Control Unit]
FIG. 9 is a flowchart illustrating processing of the job control unit 21 of the upstream machine 20 and the job control unit 31 of the downstream machine 30. Hereinafter, the processing of the job control unit 21 of the upstream device 20 will be described, but the processing of the job control unit 31 of the downstream device 30 is the same.

First, when receiving a job (step S51), the job control unit 21 of the upstream machine 20 determines whether or not the upstream machine 20 is in a printable state (step S52).
If the upstream machine 20 is ready for printing (step S52; YES), the job control unit 21 of the upstream machine 20 transmits a print start instruction to the printer control unit 22 of the upstream machine 20 (step S53).

  Here, when a stop factor is received from the printer control unit 22 of the upstream machine 20 (step S54; YES), the job control unit 21 of the upstream machine 20 determines that the stop factor is the own device or downstream from the own device. It is determined whether or not it is a jam (step S55).

  When the stop factor is neither a jam in the own device nor a jam downstream from the own device (step S55; NO), the job control unit 21 of the upstream machine 20 discharges from the upstream machine 20 according to the stop factor. The final sheet to be processed is determined (step S56). Specifically, based on the stop timing setting information, the job control unit 21 determines that the most upstream sheet among the already fed sheets is the final sheet, or delimits such as a job delimiter or a delimiter The final sheet is determined according to the stop factor, such as determining the final sheet as the final sheet.

  Next, the job control unit 21 of the upstream machine 20 transmits final paper information and a stop instruction to the printer control unit 22 of the upstream machine 20 (step S57).

After step S57 or in step S55, if the stop factor is the own device or a jam downstream from the own device (step S55; YES), the job control unit 21 of the upstream machine 20 It is determined whether or not information indicating that the stop factor has been resolved is received from the printer control unit 22 (step S58).
If information indicating that the stop factor has been eliminated is received from the printer control unit 22 of the upstream machine 20 (step S58; YES), the process returns to step S53 and the process is repeated.

  In step S54, when the stop factor is not received from the printer control unit 22 of the upstream machine 20 (step S54; NO), the job control unit 21 of the upstream machine 20 completes printing from the printer control unit 22 of the upstream machine 20. It is determined whether or not information indicating that it has been received has been received (step S59). When the information indicating that the printing is completed is not received from the printer control unit 22 of the upstream machine 20 (step S59; NO), the process returns to step S54.

  In step S59, when information indicating that printing has been completed is received from the printer control unit 22 of the upstream machine 20 (step S59; YES), the processing in the job control unit 21 ends.

[Print stop control process when there is no paper in the upstream machine]
Next, with reference to FIGS. 10 and 11, a print stop control process in the case where no paper has occurred in the upstream machine 20 during printing will be described.

FIG. 10 shows a case where the upstream machine 20 runs out of paper when trying to feed the next sheet in a situation where the sheets P1 to P5 exist in the upstream machine 20 and the downstream machine 30 during printing. It is an example.
Here, the sheets managed by the job control unit 21 of the upstream machine 20 are the sheets P3 to P5, and the sheets managed by the job control unit 31 of the downstream machine 30 are the sheets P1 and P2.

  In this situation, when the upstream machine 20 runs out of paper, as shown in FIG. 11, the printer control unit 22 of the upstream machine 20 detects the absence of paper and sends it to the job control unit 21 of the upstream machine 20. The fact that no paper has occurred is transmitted (step T1), and the fact that no paper has occurred is transmitted to the printer control unit 32 of the downstream device 30 (step T2).

  When the job control unit 21 of the upstream machine 20 receives that the absence of paper has occurred from the printer control unit 22 of the upstream machine 20, the job control unit 21 in the upstream machine 20 The final paper (paper P5) discharged from the printer is determined, and the final paper information and stop instruction are transmitted to the printer control unit 22 of the upstream machine 20 (step T3). For example, when the stop factor is no paper, the most upstream paper among the already fed paper is the final paper.

When receiving the final paper information and the stop instruction from the job control unit 21 of the upstream machine 20, the printer control unit 22 of the upstream machine 20 transmits the final paper information to the printer control unit 32 of the downstream machine 30 (step T4).
The printer control unit 22 of the upstream machine 20 stops the printing operation of the upstream machine 20 after the final sheet (paper P5) is discharged from the upstream machine 20.

  The printer control unit 32 of the downstream machine 30 that has received the absence of paper from the printer control unit 22 of the upstream machine 20 and the final paper information waits for the final paper (paper P5) to pass through the downstream machine 30. Then, the absence of paper is transmitted to the job control unit 31 of the downstream machine 30 (step T5).

  When the job control unit 31 of the downstream machine 30 receives that there is no paper from the printer control unit 32 of the downstream machine 30, the job control unit 31 finally discharges from the downstream machine 30 based on the stop timing setting information when there is no paper. The paper (paper P5) is determined, and the final paper information and stop instruction are transmitted to the printer control unit 32 of the downstream machine 30 (step T6).

  The printer control unit 32 of the downstream machine 30 stops the printing operation of the downstream machine 30 after the final sheet (paper P5) is discharged from the downstream machine 30.

  If the printer control unit 32 of the downstream machine 30 transmits that the absence of paper has occurred from the upstream machine 20 and transmits that the absence of paper has occurred to the job control unit 31 of the downstream machine 30, the timing In this case, a stop instruction is transmitted from the job control unit 31 to the printer control unit 32 for the paper P2, which is the final paper managed by the job control unit 31 of the downstream machine 30, and the papers P3 to P5 are transferred. A jam occurs when the paper stops in the downstream machine 30 or at the paper inlet of the downstream machine 30.

  In the present embodiment, the printer control unit 32 of the downstream machine 30 waits for the final paper to pass from the upstream machine 20 and transmits to the job control unit 31 of the downstream machine 30 that there is no paper, It is possible to prevent jamming in the downstream machine 30 due to the paper discharged from the upstream machine 20.

  Even when the upstream machine 20 runs out of toner, the print stop control process is performed in the same sequence as when there is no paper. However, depending on the stop factor, the upstream machine 20 may continue feeding even after the stop factor has occurred, such as when stopping at a part break or job break. For this reason, the transmission of the final paper information from the printer control unit 22 of the upstream machine 20 to the printer control unit 32 of the downstream machine 30 is not always performed at the same timing as the transmission of the stop factor. It is done at the timing when it is recognized.

[Print stop control process when toner runs out in downstream machine]
Next, with reference to FIGS. 12 and 13, a print stop control process in the case where toner runs out in the downstream machine 30 during printing will be described.

FIG. 12 shows an example in which the downstream machine 30 runs out of toner in a situation where the sheets P11 to P16 exist in the upstream machine 20 and the downstream machine 30 during printing.
Here, the papers managed by the job control unit 21 of the upstream machine 20 are the papers P13 to P16, and the papers managed by the job control unit 31 of the downstream machine 30 are the papers P11 and P12.

  In this situation, when toner runs out in the downstream machine 30, as shown in FIG. 13, the printer control unit 32 of the downstream machine 30 detects the occurrence of toner out and sends it to the printer control unit 22 of the upstream machine 20. The fact that the toner has run out is transmitted (step T11).

  When the printer control unit 22 of the upstream device 20 receives the fact that the toner has run out from the printer control unit 32 of the downstream device 30, the printer control unit 22 of the downstream device 20 transmits the fact that the toner has run out in the downstream device 30 to the job control unit 21 of the upstream device 20. (Step T12).

  When the job control unit 21 of the upstream machine 20 receives the fact that the toner has run out in the downstream machine 30 from the printer control unit 22 of the upstream machine 20, the stop timing setting information (immediate stop, job break or part break) Etc.), the final paper discharged from the upstream machine 20 is judged, and the final paper information and the stop instruction are transmitted to the printer control unit 22 of the upstream machine 20 (step T13).

When receiving the final paper information and the stop instruction from the job control unit 21 of the upstream machine 20, the printer control unit 22 of the upstream machine 20 transmits the final paper information to the printer control unit 32 of the downstream machine 30 (step T14).
In addition, the printer control unit 22 of the upstream machine 20 stops the printing operation of the upstream machine 20 after the final sheet is discharged from the upstream machine 20.

  The printer control unit 32 of the downstream machine 30 that has received out of toner from the printer control unit 22 of the upstream machine 20 and the final paper information waits for the final paper to pass through the downstream machine 30 and runs out of toner. Is transmitted to the job control unit 31 of the downstream machine 30 (step T15).

  When the job control unit 31 of the downstream machine 30 receives the fact that the toner has run out from the printer control unit 32 of the downstream machine 30, the job control unit 31 finally discharges from the downstream machine 30 based on the stop timing setting information at the time of running out of toner. The paper is determined, and the final paper information and stop instruction are transmitted to the printer control unit 32 of the downstream machine 30 (step T16).

  The printer control unit 32 of the downstream machine 30 stops the printing operation of the downstream machine 30 after the final sheet is discharged from the downstream machine 30.

  If the downstream machine 30 runs out of toner and performs control to stop the printing operation at the end of a section (when the last sheet of the currently printed section is printed), There may also be a problem that the control units 21 and 31 transmit a stop instruction to the printer control units 22 and 32 at different sections. For example, if the downstream machine 30 has only the second copy sheet at the timing when the toner runs out, and the upstream machine 20 starts feeding the third copy, the job control unit 31 of the downstream machine 30 has two copies. Since the stop instruction is issued to the printer control unit 32 at the break of the eye, and the job control unit 21 of the upstream machine 20 issues the stop instruction to the printer control unit 22 at the break of the third copy, it is discharged from the upstream machine 20. The third sheet of paper enters the downstream machine 30 and a jam occurs.

  In the present embodiment, by transmitting the final paper information from the upstream machine 20 to the downstream machine 30, the downstream machine 30 waits for the final paper to pass from the upstream machine 20 and performs job control from the printer control unit 32. Since the fact that the toner has run out is transmitted to the unit 31, it is possible to prevent jamming due to the paper discharged from the upstream machine 20.

  Even when staple staple breakage or the like occurs in the FNS 40, the print stop control process is performed in the same sequence as the case of toner depletion.

  As described above, according to the image forming system 100 in the present embodiment, in the image forming system 100 with the serial tandem configuration, the determination of the stop timing of the upstream machine 20 and the downstream machine 30 when a stop factor has occurred. It is possible to prevent the occurrence of jamming.

  When a stop factor occurs in the upstream machine 20, the stop factor and the final paper information are transmitted from the upstream machine 20 to the downstream machine 30, and after the final paper is discharged from the downstream machine 30, the printing operation of the downstream machine 30 is stopped. Therefore, the occurrence of jam in the downstream machine 30 can be prevented.

  Specifically, when a stop factor occurs in the upstream machine 20, the printer control unit 32 of the downstream machine 30 sends a stop factor to the job control unit 31 at the timing when the stop factor is received from the printer control unit 22 of the upstream machine 20. Based on the final paper information received from the printer control unit 22 of the upstream machine 20 without transmission, the stop factor is transmitted to the job control unit 31 at the timing when the final paper is passed to the downstream machine 30. A job control program used when the image forming apparatus 31 alone uses the image forming apparatus 31 that determines the final sheet managed by the apparatus and issues a stop instruction to the printer control unit 32 can be used.

  Further, when a stop factor other than a jam occurs in the downstream machine 30, the stop factor is transmitted from the downstream machine 30 to the upstream machine 20, the final paper information is transmitted from the upstream machine 20 to the downstream machine 30, and the final paper is sent downstream. Since the printing operation of the downstream machine 30 is stopped after discharging from the machine 30, the occurrence of a jam in the downstream machine 30 can be prevented.

  Specifically, when a stop factor other than a jam occurs in the downstream machine 30, the printer control unit 32 of the downstream machine 30 does not transmit the stop factor to the job control unit 31 at the timing when the stop factor occurs, and the upstream machine Based on the final paper information received from the 20 printer control units 22, the stop factor is transmitted to the job control unit 31 at the timing when the final paper is passed to the downstream machine 30, so that the job control unit 31 manages it in its own device. It is possible to use a job control program when using the image forming apparatus alone, which determines the final sheet to be processed and issues a stop instruction to the printer control unit 32.

  As described above, in the development of an image forming system having a serial tandem configuration that is configured by connecting image forming apparatuses originally developed as a single image forming apparatus in series, the change from the job control program at the time of single use is made. It is possible to minimize the development man-hours and cost of an image forming system having a series tandem configuration.

  The description in the above embodiment is an example of the image forming system according to the present invention, and the present invention is not limited to this. The detailed configuration and detailed operation of each device constituting the system can be changed as appropriate without departing from the spirit of the present invention.

  For example, although the case where two image forming apparatuses are connected has been described in the above embodiment, three or more image forming apparatuses may be connected in series along the sheet conveyance direction.

  Further, a stop factor is generated in the downstream machine 30, and the stop factor is transmitted from the printer control unit 32 of the downstream machine 30 to the printer control unit 22 of the upstream machine 20, and the printer control unit 32 of the downstream machine 30 transmits the printer of the upstream machine 20. When the final paper information is received from the control unit 22, the printer control unit 32 of the downstream machine 30 does not need to receive the final paper information from the job control unit 31 because it has acquired the final paper information. From the viewpoint of diverting the job control program of the job control unit 31 at the time of use, it is desirable that the operation of the job control unit 31 is less changed from that at the time of single use.

DESCRIPTION OF SYMBOLS 10 Paper feed unit 20 Upstream machine 21 Job control part 22 Printer control part 23 Image processing part 24 Image formation part 25 Paper conveyance part 26 Paper feed tray control part 30 Downstream machine 31 Job control part 32 Printer control part 33 Image processing part 34 Image Forming unit 35 Paper transport unit 36 Paper feed tray control unit 40 FNS
51 Operation Unit 52 Controller 100 Image Forming System

Claims (5)

In an image forming system having a tandem configuration in which a plurality of image forming apparatuses are connected in series along a paper conveyance direction,
Among the plurality of image forming apparatuses, the upstream image forming apparatus in the sheet conveying direction determines a final sheet according to the stop factor when the stop factor is generated in the upstream image forming apparatus, and the After the final sheet is discharged from the upstream image forming apparatus, the printing operation of the upstream image forming apparatus is stopped, and information indicating the stop factor and the final sheet is displayed downstream of the upstream image forming apparatus. An upstream control unit for transmitting to the image forming apparatus on the side,
The downstream image forming apparatus includes a downstream job control unit that manages jobs, and a downstream printer control unit that controls image formation and sheet conveyance.
The downstream printer control unit, based on the information indicating the final paper received from the upstream controller, controls the timing of transmitting the stop factor received from the upstream control unit to the downstream job control unit And
The downstream job control unit determines a final sheet in the downstream image forming apparatus based on the stop factor received from the downstream printer control unit , and information indicating the final sheet and the downstream image A downstream stop instruction for stopping the printing operation of the forming apparatus is transmitted to the downstream printer control unit;
The downstream printer control unit discharges the final sheet from the downstream image forming apparatus on the basis of the information indicating the final sheet received from the downstream job control unit and the downstream stop instruction. images forming system Ru stops the printing operation on the side of the image forming apparatus. The upstream control unit includes an upstream job control unit that manages jobs, and an upstream printer control unit that controls image formation and paper conveyance,
When the stop factor generated in the upstream image forming apparatus is not a jam,
The upstream printers control unit transmits the stop cause transmits to said upstream Gawaji job control unit, the stop cause the downstream printers control unit,
Said upstream Gawaji job control unit determines the final paper in response to the stop factor received from the upstream printers control unit, the printing operation of the image forming apparatus information and the upstream shows the final paper transmits upstream stop instruction for stopping the upstream printers control unit,
The upstream printers control unit, on the basis of the upstream Gawaji job information indicating the final paper received from the control unit and the upstream stop instruction, and discharging the final paper from the image forming apparatus of the upstream the stops the print operation of the upstream side of the image forming apparatus transmits the information indicating the last sheet to the downstream printers controller after,
The downstream printers control unit, based on the information indicating the final paper received from the upstream printers control unit, the upstream in the final paper to the image forming apparatus of the downstream side is paper passing timing transmitting the stop factor received from printers control unit to the downstream Gawaji job control unit,
The image forming system according to claim 1. The upstream control unit includes an upstream job control unit that manages jobs, and an upstream printer control unit that controls image formation and paper conveyance,
When a jam occurs as the stop factor in the upstream image forming apparatus,
The upstream printers control unit transmits the stop factor to the upstream Gawaji job controller transmits the stop factor to the downstream printers control unit, the final paper in response to the occurrence position of the jam determined, and transmits the final paper stops the printing operation of the upstream side of the image forming apparatus after discharged from the image forming apparatus of the upstream, the information indicating the last sheet to the downstream printers controller ,
The downstream printers control unit, based on the information indicating the final paper received from the upstream printers control unit, the upstream in the final paper to the image forming apparatus of the downstream side is paper passing timing transmitting the stop factor received from printers control unit to the downstream Gawaji job control unit,
The image forming system according to claim 1. In an image forming system having a tandem configuration in which a plurality of image forming apparatuses are connected in series along a paper conveyance direction,
Among the plurality of image forming apparatuses, an image forming apparatus on the downstream side in the paper transport direction includes a downstream job control unit that manages jobs, and a downstream printer control unit that controls image formation and paper transport. ,
The downstream printer control unit, when a stop factor other than a jam occurs in the downstream image forming apparatus, transmits the stop factor to the image forming apparatus upstream of the downstream image forming apparatus ,
The image forming apparatus of the upstream, determines the final paper in response to the stop factor received from the downstream printer controller, the upstream side of the image after discharging the last sheet from the image forming apparatus of the upstream An upstream control unit that stops the printing operation of the forming apparatus and transmits information indicating the final sheet to the downstream image forming apparatus;
The downstream printer control unit, based on the information indicating the final paper received from the upstream controller to control the timing of transmitting the stop factor to the downstream job control unit,
The downstream job control unit determines a final sheet in the downstream image forming apparatus based on the stop factor received from the downstream printer control unit , and information indicating the final sheet and the downstream image A downstream stop instruction for stopping the printing operation of the forming apparatus is transmitted to the downstream printer control unit;
The downstream printer control unit discharges the final sheet from the downstream image forming apparatus on the basis of the information indicating the final sheet received from the downstream job control unit and the downstream stop instruction. An image forming system for stopping the printing operation of the image forming apparatus on the side. Before Symbol upstream control unit comprises an upstream job control unit for managing jobs, an upstream printer control unit for controlling the image formation and conveyance of the sheet, and
The downstream printers control unit transmits the stop factor to the upstream printers control unit,
The upstream printers control unit transmits the stop factor received from the downstream printers control unit to the upstream Gawaji job control unit,
Said upstream Gawaji job control unit determines the final paper in response to the stop factor received from the upstream printers control unit, the printing operation of the image forming apparatus information and the upstream shows the final paper transmits upstream stop instruction for stopping the upstream printers control unit,
The upstream printers control unit, on the basis of the upstream Gawaji job information indicating the final paper received from the control unit and the upstream stop instruction, and discharging the final paper from the image forming apparatus of the upstream the stops the print operation of the upstream side of the image forming apparatus transmits the information indicating the last sheet to the downstream printers controller after,
The downstream printers control unit, based on the information indicating the final paper received from the upstream printers control unit, the stop factor in the final paper to the image forming apparatus of the downstream side is paper passing timing and it transmits to the downstream Gawaji job control unit,
The image forming system according to claim 4.

Images