Patent Description:
Various technologies have been developed that detect a defect in an image formed by an image forming apparatus, based on a result of reading the image. For example, when a defect is detected, a technology is known that inserts a slip sheet (insertion sheet) between a bundle of printed materials so that a printed material in which the defect is detected is easily found from the bundle of printed materials stacked on a sheet ejection tray.

<CIT> discloses such an image forming apparatus that displays the position of an inserted slip sheet on a display unit.

However, since the appearance of a conveyance medium such as a slip sheet inserted into the bundle of printed materials is not identified, it may take time to find the conveyance medium. When it takes time to find the conveyance medium, it takes more time to find the printed material in which the defect is detected. For these reasons, the overall operation time may be affected due to additional work, for example, checking the defective printed material and replacing the defective printed material with a printed material without defects accordingly.

<CIT> discloses an image forming apparatus including a printing unit, a verification unit, an insertion unit, and a display unit. <CIT> discloses in a case where defects have occurred in four places within a printing data zone of a sheet P1, an interleaf sheet P2 is printed with four code images. <CIT> discloses an inspection system including an inspection apparatus configured to examine, for each print, whether a defect has occurred on at least one print side based on a read image of the at least one print side and an image that corresponds to a read image, and configured to notify a printer of sheet identification information about a sheet on which an original image of a certain page is printed. <CIT> discloses an image inspection device to enable a user to easily perform confirmation work as to whether a problem exists in the quality of an output image when an image failure is detected in the output image formed on a sheet. <CIT> discloses a method to support a search for a defective printed matter from among printed matters which are printed in large quantities.

An object of the present disclosure is to facilitate finding of a printed material having a defect corresponding to a conveyance medium by recognizing the appearance of the conveyance medium such as a slip sheet to be ejected when the defect is detected in an image on the conveyance medium.

Descriptions are given of an image forming system according to a first embodiment of the present disclosure, with reference to the drawings.

<FIG> is a diagram illustrating an overall configuration of an image forming system, according to embodiments of the present disclosure.

An image forming system <NUM> includes an image forming apparatus <NUM>, a user terminal <NUM>, a management server <NUM>, and a digital front end (DFE) <NUM>.

The image forming apparatus <NUM> is an apparatus that forms an image, and is, for example, a color production printer, a laser printer, or an inkjet printer. The image forming apparatus <NUM> receives image data from the DFE <NUM> and prints the image on a sheet based on the received image data. Note that "sheet" is an example of a conveyance medium on which an image is formed.

The user terminal <NUM> is a terminal that receives an operation from a user and instructs to print an image. Specifically, the user terminal <NUM> transmits job data including image data to the DFE <NUM> or the management server <NUM>. The user terminal <NUM> transmits information indicating a threshold in color stabilization processing to the DFE <NUM> in response to an operation of the user. In addition, the user terminal <NUM> receives display control by the DFE <NUM> and displays a screen indicating an execution status of the color stabilization processing.

The management server <NUM> adds the job data as a queue to a memory that stores the job data waiting for printing in response to the receipt of the job data from the user terminal <NUM>. The management server <NUM> extracts job data from the queue in the order in which the job data is added to the queue or in accordance with a priority set appropriately. Then, the management server <NUM> transmits the job data to the DFE <NUM>.

The DFE <NUM> is an apparatus that controls the image forming apparatus <NUM>, for example, a DFE. The DFE <NUM> is communicably connected to the image forming apparatus <NUM>, the user terminal <NUM>, and the management server <NUM>.

When the DFE <NUM> receives job data with a signal that instructs to print the image from the user terminal <NUM> or the management server <NUM>, the DFE <NUM> converts the job data into image data in a format that is processed by the image forming apparatus <NUM>, using a raster image processor (RIP) engine included in the image forming apparatus <NUM>. Then, the DFE <NUM> transmits the converted image data to the image forming apparatus <NUM>.

<FIG> is a diagram illustrating a hardware configuration of an image forming apparatus of the image forming system of <FIG>.

The image forming apparatus <NUM> includes a printer <NUM>, an inspection device <NUM>, a stacker <NUM>, and an insertion device <NUM>.

The printer <NUM> receives the job data including a print image (rasterized image) from an external apparatus such as the DFE <NUM>. Then, the printer <NUM> executes printing in response to an execution instruction based on the received job data or an execution instruction based on the job data stored in the printer <NUM> by a user's operation on an operation panel <NUM>.

The printer <NUM> has a configuration in which photoconductor drums <NUM>, <NUM>, <NUM>, and <NUM> are disposed along an intermediate transfer belt <NUM>. The photoconductor drums <NUM>, <NUM>, <NUM>, and <NUM> form yellow (Y), magenta (M), cyan (C), and black (K) toner images, respectively. The intermediate transfer belt <NUM> is a moving unit of an endless loop. Images of the respective colors are developed with toner on the respective surfaces of the photoconductor drums <NUM>, <NUM>, <NUM>, and <NUM> and are transferred and superimposed one after another onto the surface of the intermediate transfer belt <NUM> to form a full-color image.

The full-color image borne on the intermediate transfer belt <NUM> is transferred onto the sheet by a transfer roller <NUM>. The sheet is fed from a sheet feeding tray <NUM> and conveyed by a transfer roller <NUM>. Then, the sheet is further conveyed, and the toner is fixed to the sheet by a fixing roller <NUM>. Note that, when outputting a slip sheet without printing, another sheet feeding tray for the slip sheet may be provided separate from the sheet feeding tray <NUM>.

In the case of duplex printing, after the image is formed on the front side, the sheet is conveyed to a sheet reverse passage <NUM> in the sheet conveyance passage, then is reversed, and is conveyed again to the position of the transfer roller <NUM>.

The inspection device <NUM> is a device that inspects printed sheets by the printer <NUM>. Each of the printed sheets to be inspected is referred to as a first conveyance medium in the present disclosure. The inspection device <NUM> includes a first inline sensor <NUM>, a second inline sensor <NUM>, and an operation panel <NUM>. The inspection device <NUM> may not include the operation panel <NUM>. In this case, the inspection device <NUM> may be configured to receive an operation through the operation panel <NUM> of the printer <NUM> or a computer connected via a communication network.

The first inline sensor <NUM> and the second inline sensor <NUM> read the images fixed on both sides of the sheet by the fixing roller <NUM> and obtain read image data indicating the read images. The number of inline sensors is not limited to two and may be one or three or more as long as both sides of the sheet are read. An inline sensor includes a light source and a line image sensor. The light source irradiate light onto a sheet passing over a reading position. The line image sensor includes a plurality of imaging elements aligned one dimensionally in the width direction of a sheet. The plurality of imaging elements optically converts reflected light reflected on the sheet for each pixel to read the reflected light. The inline sensor reads an image printed on the sheet as a two-dimensional image by repeatedly performing an operation of reading the image for one line in the width direction of the sheet, in accordance with the sheet passing operation over the reading position. Further, the line image sensor captures read images of three colors of red, green, and blue (RGB). The inline sensor is an example of an image acquisition unit that acquires the image on the sheet. The image acquisition unit may acquire an image other than the read image data as long as the image is an image for detecting a defect, such as image data or a thumbnail image of image data.

The stacker <NUM> includes a sheet ejection tray <NUM> and stacks printed sheets ejected from the printer <NUM> via the inspection device <NUM> on the sheet ejection tray <NUM>. The stacker <NUM> and the sheet ejection tray <NUM> are configured to receive and stack the printed sheets and the slip sheets. The stacker <NUM> may have a plurality of sheet ejection trays <NUM>.

The insertion device <NUM> includes an insertion tray <NUM> and supplies slip sheets under the control of the printer <NUM>. Specifically, the printer <NUM> stores setting information for selecting a slip sheet feeding tray. In a case where the setting information indicates that the slip sheet feeding tray is the insertion tray <NUM>, the printer <NUM> causes the insertion device <NUM> to supply the slip sheet from the insertion tray <NUM> when a job for ejecting the slip sheet is executed.

The present embodiment is given providing that, for example, that the rasterized image is in the CMYK format (format in a subtractive color mode including cyan, magenta, yellow, and black) with <NUM>-bit colors and <NUM> dpi resolution, and the read image is in the RGB format with <NUM>-bit colors and <NUM> dpi resolution. However, embodiments of the present disclosure are not limited to the above-described data formats in image formation.

<FIG> is a diagram illustrating a hardware configuration of a printer of the image forming system of <FIG>.

The printer <NUM> includes a controller <NUM>, a short-range communication circuit <NUM>, an engine controller <NUM>, the operation panel <NUM>, and a network I/F <NUM>.

The controller <NUM> includes a central processing unit (CPU) <NUM> that is a main part of a computer, a system memory (MEM-P) <NUM>, a north bridge (NB) <NUM>, a south bridge (SB) <NUM>, an application specific integrated circuit (ASIC) <NUM>, a local memory (MEM-C) <NUM> that is a memory unit, a hard disk drive (HDD) controller <NUM>, and a hard disk (HD) <NUM> that is a memory.

The NB <NUM> and the ASIC <NUM> are connected by an accelerated graphics port (AGP) bus <NUM>.

The CPU <NUM> is a control device that performs overall control of the printer <NUM>. The NB <NUM> is a bridge configured to connect the CPU <NUM>, the MEM-P <NUM>, the SB <NUM>, and the AGP bus <NUM>. The NB <NUM> includes a memory controller that controls reading from and writing to the MEM-P <NUM>, a peripheral component interconnect (PCI) master, and an AGP target.

The MEM-P <NUM> includes a read only memory (ROM) 1102a and a random access memory (RAM) 1102b. The ROM 1102a is a memory to store programs and data for implementing various functions of the controller <NUM>. The RAM 1102b is a memory configured to deploy programs, data or to render print data for memory printing. The program stored in the RAM 1102b may be provided as a file in an installable format or an executable format that the program is recorded in a computer-readable storage medium such as a compact disc-read only memory (CD-ROM), a compact disc-recordable (CD-R), or a digital versatile disc (DVD).

The SB <NUM> is a bridge configured to connect the NB <NUM> to PCI devices and peripheral devices. The ASIC <NUM> is an integrated circuit (IC) for image process having a hardware element for image process and has a role of a bridge that connects the AGP bus <NUM>, the PCI bus <NUM>, the HDD controller <NUM>, and the MEM-C <NUM> to each other.

The ASIC <NUM> includes a PCI target, an AGP master, an arbiter (ARB) serving as a core of the ASIC <NUM>, a memory controller that controls the MEM-C <NUM>, a plurality of direct memory access controllers (DMAC) that rotates image data by hardware logic, and a PCI unit that transfers data between a scanner section <NUM> and a printer section <NUM> via the PCI bus <NUM>. A universal serial bus (USB) interface or an Institute of Electrical and Electronics Engineers <NUM> (IEEE <NUM>) interface may be connected to the ASIC <NUM>.

The MEM-C <NUM> is a local memory used as a copy image buffer and a code buffer. The HD <NUM> is a memory that stores image data, font data used in printing, and forms. The HD <NUM> controls reading or writing of data from or to the HD <NUM> under the control of the CPU <NUM>.

The AGP bus <NUM> is a bus interface for a graphics accelerator card that has been proposed to speed up graphics processing. The AGP bus <NUM> is a bus that directly access the MEM-P <NUM> at high throughput to speed up a graphics accelerator card.

The short-range communication circuit <NUM> includes a short-range communication antenna 1120a. The short-range communication circuit <NUM> is a communication circuit that communicates in compliance with the near field radio communication (NFC) or the Bluetooth®.

The engine controller <NUM> includes the scanner section <NUM> and the printer section <NUM>. The operation panel <NUM> includes a panel display 12a and a hard keys 12b. The panel display 12a is, e.g., a touch panel that displays current settings or a selection screen that receives the user input. The hard keys 12b includes, e.g., a numeric keypad and a start key. The numeric keypad receives setting values of image forming parameters such as an image density parameter. The start key receives an instruction to start copying.

The controller <NUM> controls the overall printer <NUM> and controls, for example, drawing, communication, and input from the operation panel <NUM>. The scanner section <NUM> reads the image formed on the conveyance medium such as a sheet and generates image data. The printer section <NUM> includes a transfer device that transfers the image using a color material such as a toner image onto the conveyance medium such as the sheet, a fixing device that fixes the image, a heating device, a drying device, and performs image formation on the sheet. Further, the scanner section <NUM> or the printer section <NUM> executes image process such as error diffusion and gamma conversion.

The network I/F <NUM> is an interface that performs communication of data through the communication network. The short-range communication circuit <NUM> and the network I/F <NUM> are electrically connected to the ASIC <NUM> via the PCI bus <NUM>.

<FIG> is a diagram illustrating a hardware configuration of an inspection device of the image forming apparatus of <FIG>.

The inspection device <NUM> includes the first inline sensor <NUM>, the second inline sensor <NUM>, the operation panel <NUM>, and a CPU <NUM>, a ROM <NUM>, a RAM <NUM>, an HDD/solid state drive (SSD) <NUM>, a network I/F <NUM>, and an external I/F <NUM>. The CPU <NUM>, the ROM <NUM>, the RAM <NUM>, and the HDD/SSD are configured by a computer.

The CPU <NUM> reads programs stored in the ROM <NUM> or the HDD/SSD <NUM> and stores the programs in the RAM <NUM>. Then, the CPU <NUM> executes various processes in accordance with the program stored in the RAM <NUM>. The processes are described below.

The ROM <NUM> is a non-volatility auxiliary memory device. The ROM <NUM> stores programs such as a basic input/output system (BIOS) that is programed basic operations of the inspection device <NUM>.

The RAM <NUM> is a volatile main memory device. The RAM <NUM> is used as a working area of the CPU <NUM>.

The HDD/SSD <NUM> is a large capacity non-volatility auxiliary memory device. The HDD/SSD <NUM> stores received image data, programs for various processes, and setting information. The processes are described below.

The network I/F <NUM> is, for example, a local area network (LAN) card, and is a relay unit for communicating with other devices via a communication network.

The external I/F <NUM> is a relay unit for communicating with the devices connected as external devices, such as the DFE <NUM>, the printer <NUM>, and the stacker <NUM>.

Note that the DFE <NUM> has the substantially same hardware configuration as the hardware configuration of the inspection device <NUM>, except that the DFE <NUM> has the first inline sensor <NUM>, the second inline sensor <NUM>, and the operation panel <NUM>.

<FIG> is a diagram illustrating functions of the DFE of the image forming system of <FIG>.

The DFE <NUM> includes a system control unit <NUM>, a job receiving unit <NUM>, a storage unit <NUM>, a job transmission unit <NUM>, and a display control unit <NUM>. Each of the units of the DFE <NUM> is achieved by a CPU included in the DFE <NUM> executing processing defined in programs stored in a ROM included in the DFE <NUM>.

The system control unit <NUM> includes a job information processing unit <NUM>, a rasterized image processing unit <NUM>, a control information storage unit <NUM>, and a gradation correcting unit <NUM>.

The job information processing unit <NUM> processes information about a job included in the job data.

The rasterized image processing unit <NUM> performs predetermined color conversion processing on the CMYK values or the RGB values of the input image data using a RIP engine and converts the CMYK values or the RGB values into image data in a CMYK format suitable for the image forming apparatus <NUM>.

The control information storage unit <NUM> stores control information controlled by the system control unit <NUM>.

The gradation correcting unit <NUM> corrects a gradation of the image data converted by the rasterized image processing unit <NUM>.

The job receiving unit <NUM> receives the job data from the user terminal <NUM> or the management server <NUM> via the communication network <NUM>.

The storage unit <NUM> stores the received job data.

The job transmission unit <NUM> transmits the job data to the image forming apparatus <NUM>. The job data is generated through processing by the system control unit <NUM>. The job data transmitted to the image forming apparatus <NUM> includes rasterized image data and job information indicating attributes of the job.

The display control unit <NUM> controls to display display information generated by the system control unit <NUM> on the display device <NUM>.

<FIG> is a diagram illustrating functions of the printer of the image forming apparatus of <FIG>.

The printer <NUM> includes a system control unit <NUM>, a display control unit <NUM>, a network I/F control unit <NUM>, an external I/F control unit <NUM>, a storage unit <NUM>, a mechanism control unit <NUM>, a job receiving unit <NUM>, an image processing control unit <NUM>, and a printing control unit <NUM>. Each of these units of the printer <NUM> is achieved by the CPU <NUM> or the ASIC <NUM> of the printer <NUM> executing a process defined in programs stored in the MEM-P <NUM> or the MEM-C <NUM>.

The system control unit <NUM> controls the overall operation of the printer <NUM>. The system control unit <NUM> includes a job information processing unit <NUM>, a rasterized image processing unit <NUM>, and a job information generation unit <NUM>.

The job information processing unit <NUM> processes job information included in the job transmitted from the DFE <NUM>. The rasterized image processing unit <NUM> processes the rasterized image data included in the job data transmitted from the DFE <NUM>. The job information generation unit <NUM> generates job information for inserting the slip sheet in response to receipt of information to be inserted the slip sheet (slip sheet insertion information) from the inspection device <NUM>. Note that an image may be printed on the slip sheet in advance, or handwritten text or image may be included. The image of the slip sheet may not be defined in advance.

Note that the slip sheet (insertion sheet) may be a sheet such as cut paper that is a conveyable medium by the printer <NUM>. The conveyance medium may be a colored sheet, a blank sheet, or a blank sheet having a size different from the size of the sheet of the job, a film sheet, a plastic sheet, as long as the conveyance medium has identification information of the slip sheet (conveyance medium) and is stacked in a sheet feeding tray provided for the printer <NUM>, to be conveyed and output according to an output instruction of the slip sheet. The slip sheet is referred to as a second conveyance medium while a printed sheet is referred to as a first conveyance medium as described above. The information printed on the slip sheet (second conveyance medium) may be printed by an image forming unit of the printer <NUM>. Alternatively, the information printed on the slip sheet may be applied to or printed on the slip sheet in advance. The image forming unit of the printer <NUM> controls the printer section <NUM> to form an image including the identification information of the second conveyance medium on the second conveyance medium. Accordingly, even when a plurality of defective printed sheets and a plurality of slip sheets corresponding to the defective printed sheets are ejected to an ejection device such as a sheet ejection tray, it is easy for a user to distinguish the slip sheets and confirm the defective printed sheets corresponding to each of the slip sheets.

The display control unit <NUM> controls to display various types of information including job information on the operation panel <NUM>. The network I/F control unit <NUM> controls the network I/F <NUM> and controls connection with a communication network. When another device is connected to the printer <NUM>, the external I/F control unit <NUM> controls connection with the connected device. The storage unit <NUM> stores various types of information including job information.

The mechanism control unit <NUM> controls operations of mechanisms included in the printer <NUM>, such as operations of a mechanism that performs sheet conveyance and operations of a mechanism that performs transfer process in the printer <NUM> including the printer section <NUM>. The job receiving unit <NUM> receives the job data from the DFE <NUM>. The image processing control unit <NUM> processes the print image transferred by the mechanism control unit <NUM>. The printing control unit <NUM> controls image formation on the conveyance medium. The mechanism control unit <NUM>, the image processing control unit <NUM>, and the printing control unit <NUM> cooperate with each other to function as the image forming unit that forms an image on the conveyance medium. Further, the image acquisition device such as the inline sensor may acquire an image after toner is fixed to the conveyance medium by the fixing roller <NUM> or the image before the conveyance medium enters the fixing roller <NUM> after the image is transferred by the transfer roller <NUM>.

<FIG> is a diagram illustrating functions of the inspection device of the image forming apparatus of <FIG>.

The inspection device <NUM> includes a system control unit <NUM>, a display control unit <NUM>, a network I/F control unit <NUM>, an external I/F control unit <NUM>, a storage unit <NUM>, a mechanism control unit <NUM>, a reading unit <NUM>, a master image generation unit <NUM>, and a difference image generation unit <NUM>. Each of these units is achieved by the CPU <NUM> or the ASIC <NUM> of the inspection device <NUM> executing processing defined in programs stored in the MEM-P <NUM> or the MEM-C <NUM> of the inspection device <NUM>.

The system control unit <NUM> controls the overall operation of inspection device <NUM>. The system control unit <NUM> includes a control information storage unit <NUM>, a job information processing unit <NUM>, a defect determination unit <NUM>, and an ejection control unit <NUM>.

The control information storage unit <NUM> stores control information controlled by the system control unit <NUM>. Further, the control information storage unit <NUM> temporarily stores received job information while the job information is an object to be controlled.

The job information processing unit <NUM> extracts information to be processed by a post-processing device (for example, a device that performs post-processing such as the stacker <NUM>) from job information and transmits the extracted information to the post-processing device via the external I/F control unit <NUM>. Further, the job information processing unit <NUM> transfers job information excluding information to be processed by the post-processing device, to the master image generation unit <NUM>, the defect determination unit <NUM>, the reading unit <NUM>, and the mechanism control unit <NUM>.

The display control unit <NUM> controls to display various types of information including an inspection result on the operation panel <NUM> or a different device. The different device includes a terminal device used by a user, such as a personal computer (PC) or a tablet PC, the DFE <NUM>, the printer <NUM>. The display control unit <NUM> performs process of returning information stored in the inspection device <NUM> in response to a request from software such as a web browser executing in the different device. Further, the display control unit <NUM> and software executing in the different device transmit information of the inspection device <NUM> to the different device using a bidirectional communication protocol such as WebSocket and display the information in real time. For example, when software executing in the different device displays a list of defective printed sheets by accessing the inspection device <NUM>, the list is automatically updated each time a defect occurs, and information of a defective printed sheet or information of the slip sheets is additionally displayed. The display control unit <NUM> may be included in the inspection device <NUM> as a web server or may be included in a cloud server that receives information of the inspection result from the inspection device <NUM>. The operation panel <NUM>, a display of the different device, and software such as the web browser are examples of a display unit on which the display control unit <NUM> of the present embodiment displays information.

The network I/F control unit <NUM> controls the network I/F <NUM>. The external I/F control unit <NUM> controls the external I/F <NUM>.

The storage unit <NUM> stores various types of information. Specifically, job execution history information related to the job that the control has been ended, and a difference image data indicating the difference between the read image data and the master image data are stored.

The mechanism control unit <NUM> controls an operation of a mechanism included in the inspection device <NUM> such as conveyance of the sheet.

The reading unit <NUM> controls the first inline sensor <NUM> and the second inline sensor <NUM> to read the image formed on a sheet by the printer <NUM>, and to generate read image data indicating the read image.

The master image generation unit <NUM> generates master image data based on the rasterized image data. Specifically, the master image generation unit <NUM> converts rasterized image data in the CMYK format into master image data in the RGB format.

Note that the master image data is data serving as a reference for comparison with the read image data and is used as the correct data when printed correctly. The master image data may be created by reading the sheet on which a reference image is printed with the scanner section <NUM>, the inline sensor, or a scanner of an external device.

The difference image generation unit <NUM> generates difference image data indicating a difference in density values (RGB values) for each pixel between the master image data and the read image data.

The defect determination unit <NUM> determines whether the printed image has a defect by comparing the difference image data with a predetermined threshold. The threshold is information (value) serving as a criterion for determining that the image has the defect. The defect determination unit <NUM> refers to the threshold and determines that the image has the defect if the difference image data has an area exceeding the threshold. The threshold is, for example, a value indicating that a difference (comparison result) between density values of each pixel included in the difference image data is equal to or greater than a predetermined density value, or a value indicating an area of a portion where pixels having a difference equal to or greater than the predetermined density value are continuous. The setting of the threshold is changed by the user so that the threshold is increased (the criterion is relaxed) or decreased (the criterion is tightened). A defect refers to a portion of image data determined to be different from an image desired by the user (for example, master image data) when a determination result determined by the defect determination unit <NUM> exceeds a threshold. The defect includes, for example, a spot, a streak, a positional deviation of the image, a difference in color, and a void in color.

Note that the defect determination method may be a determination method of determining whether the value of a printed image exceeds a set threshold (difference from ideal image data) based on a read image data obtained by reading ideal image data in advance of printing, other than the above-described method of comparing master image data and read image data. Further, before defect determination process is performed, correction processing may be performed to increase the accuracy of the determination processing. The correction processing is processing such as skew correction of read image data for correcting read image data of a medium conveyed in a skewed manner to a correct orientation or position, or flare correction for correcting a white light portion in read image data at the time of reading.

When the defect determination unit <NUM> determines that the image has a defect, the ejection control unit <NUM> controls to eject the slip sheet (second conveyance medium) indicating that the image has the defect. The slip sheet is a sheet to be inserted between printed sheets stacked as a bundle of printed sheets on the stacker <NUM>.

Specifically, when the defect determination unit <NUM> determines that the image has the defect, the ejection control unit <NUM> determines whether to insert the slip sheet based on a threshold of an insertion interval set in advance. When the ejection control unit <NUM> determines that the slip sheet is to be inserted, information for inserting the slip sheet (slip sheet insertion information) is generated and transmitted to the printer <NUM>. Note that the ejection control unit <NUM> may instruct the printer <NUM> to feed a predetermined slip sheet from the sheet feeding tray provided in the printer <NUM> and eject the slip sheet without printing. The predetermined slip sheet includes, for example, a colored sheet or a sheet having a size different from the size of a sheet used in a print job.

Descriptions are given of information that the image forming system <NUM> controls.

<FIG> is a diagram illustrating items of job information, according to embodiments of the present disclosure.

Job information <NUM> is information included in job data generated by the DFE <NUM> or the printer <NUM>. The job information <NUM> includes items "JOB GENERATION SOURCE", "GENERATION TIME", "PAGE ID", "PRINT FACE", "SHEET ID", "COPY ID", "JOB ID", "SHEET TYPE", "SHEET SIZE", "JOB TYPE", and "SLIP SHEET ID".

The value of the item "JOB GENERATION SOURCE" is a value indicating the generation source of the print job data and is either a "DFE JOB" or an "INTERNAL JOB". When the job information is included in the job data to be transmitted to the image forming apparatus <NUM> by the DFE <NUM>, the value of the item "JOB GENERATION SOURCE " is the "DFE JOB". When the job information generation unit <NUM> of the printer <NUM> generates the job data for the slip sheet, since the job data is generated inside the image forming apparatus <NUM>, the value of the item "JOB GENERATION SOURCE" is the "INTERNAL JOB".

The value of the item "GENERATION TIME" is a value indicating the time at which the generation source generated the job information.

The value of the item "PAGE ID" is a numerical value to identify the print image and is incremented by one for output of each page starting from activation of the power source. The numerical value is set in the item "PAGE ID" when printing is executed.

The value of the item "PRINT FACE" is a value to identify whether the print image is to be printed on one side in single-sided printing, on the front face in duplex printing (front in duplex), or on the back face in duplex printing (back in duplex).

The value of the item "SHEET ID" is a numerical value to identify a sheet. When the duplex printing is performed, two page IDs are given to the same sheet ID. The value of the item "SHEET ID" is incremented by one for process of each page starting from activation of the power source. A numerical value is set in the item "SHEET ID" when printing is executed.

The value of the item "COPY ID" is a numerical value to identify a unit of copy and is incremented by one for output of each copy starting from activation of the power source. A numerical value is set in the item "COPY ID" when printing is executed.

The value of the item "JOB ID" is a numerical value to identify the job unit and is incremented by one for output of each job starting from activation of the power source. A numerical value is set in the item "JOB ID" when printing is executed.

The value of the item "SHEET TYPE" is a value indicating the type of the sheet. The value of the item "SHEET SIZE" is a value indicating the size of the sheet. Note that a sheet used as a slip sheet is selectable based on the settings, either a sheet used in the print job in which the defect is detected, or a sheet stacked on a designated sheet feeding tray. When a sheet to be used as a slip sheet is a sheet stacked on the designated sheet feeding tray, an inexpensive sheet is used to be dedicated to the slip sheet, and the cost is reduced.

The value of the item "JOB TYPE" is a value indicating whether the job is a target of defect detection, a non-target of defect detection, or a slip sheet for defect detection identification. When the job information generation unit <NUM> of the printer <NUM> generates the job data for slip sheets, the value of the item "JOB TYPE" is a value indicating a slip sheet for defect detection identification. When the value of the item "JOB TYPE" is a value indicating a non-target of defect detection or a slip sheet for defect detection identification, the defect determination unit <NUM> does not execute processing.

The value of the item "SLIP SHEET ID" is an identifier to identify the slip sheet. The value of the item "SLIP SHEET ID" is notified from the inspection device <NUM> to the printer <NUM>. In a case of a job generated by the DFE <NUM> or a job generated by the printer <NUM> for other than a slip sheet, a slip sheet ID does not exist. For this reason, the value "-<NUM>" is set in the item "SLIP SHEET ID" as a value indicating that a slip sheet ID does not exist.

Next, descriptions are given of operations of the image forming system <NUM>.

<FIG> is a sequence diagram illustrating an example of print process without the slip sheet.

When the job receiving unit <NUM> of the DFE <NUM> receives print job data from the user terminal <NUM> or the management server <NUM>, the job information processing unit <NUM> generates job information for each page of the print job. Then, the job transmission unit <NUM> of the DFE <NUM> transmits job information (for example, page n) to the printer <NUM> (step S101).

When the job receiving unit <NUM> of the printer <NUM> receives the job information (page n), the job information processing unit <NUM> of the printer <NUM> performs processing such as addition of the numerical value indicating the page ID to update the received job information (page n) and transmits the updated job information to the inspection device <NUM> via the external I/F control unit <NUM> (step S102).

When the job receiving unit <NUM> of the DFE <NUM> receives the job data from the user terminal <NUM> or the management server <NUM>, the rasterized image processing unit <NUM> of the DFE <NUM> performs processing of converting each page into the rasterized image data. The job information processing unit <NUM> and the rasterized image processing unit <NUM> of the DFE <NUM> perform processing in parallel, and the job information that completes processing first is transmitted to the printer <NUM> first. For example, the DFE <NUM> generates and transmits job information for page n+<NUM> and page n+<NUM> before starting transmission of the rasterized image data (page n). Then, the printer <NUM> updates the received job information and transmits the updated job information to the inspection device <NUM> (steps S103 to S106).

Then, the rasterized image processing unit <NUM> of the DFE <NUM> generates rasterized image data (page n) corresponding to the job information (page n). The job transmission unit <NUM> transmits the rasterized image (page n) to the printer <NUM> (step S107). The rasterized image processing unit <NUM> of the printer <NUM> performs processing for the rasterized image data and transmits the processed rasterized image data to the inspection device <NUM> (step S108).

The master image generation unit <NUM> of the inspection device <NUM> generates master image data (page n) according to the job information (page n) and the rasterized image data (page n). Then, in accordance with the job information, the inspection device <NUM> associates the order of pages detected by the first inline sensor <NUM> and the second inline sensor <NUM> with the generated master image data and stores the association result in the storage unit <NUM>.

The image processing control unit <NUM>, the printing control unit <NUM>, and the mechanism control unit <NUM> of the printer <NUM> execute print process in accordance with the job information (page n) (step S109). The printed sheet (page n) is conveyed to the inspection device <NUM>.

In steps S110 to S115, the DFE <NUM> and the printer <NUM> perform processing on the rasterized image (pages n+<NUM> and n+<NUM>) in the same way. Then, the reading unit <NUM> of the inspection device <NUM> acquires read image data (pages n, n+<NUM>, n+<NUM>) read by the first inline sensor <NUM> and the second inline sensor <NUM> (steps S116 to S118).

Subsequently, the difference image generation unit <NUM> of the inspection device <NUM> generates difference image data indicating a difference between the master image data and the read image data for each page. The defect determination unit <NUM> determines whether the image includes any defect based on the generated difference image data and generates defect determination information. Then, the ejection control unit <NUM> executes inspection process including an inspection of whether to eject the slip sheet (second conveyance medium). Details of the inspection process are described below.

<FIG> is a sequence diagram illustrating an example of the print process with the slip sheet.

In the print process with slip sheet illustrated in <FIG>, step S201 and step S202 are the same as step S101 and step S102, respectively, of the print process without slip sheet illustrated in <FIG>.

In the case the print process with slip sheet, for example, in step S203, the defect determination unit <NUM> determines that the image includes a defect for the page n-<NUM> on which print output has already been performed, and the ejection control unit <NUM> determines that the slip sheet is to be inserted by the inspection process described below.

The ejection control unit <NUM> of the inspection device <NUM> replaces the "sheet count value of the previously inserted slip sheet" stored in the control information storage unit <NUM> with the "sheet count value" of the sheet currently determined that the sheet has a defect. The "sheet count value of the previously inserted slip sheet" is the number of pages serving as a reference for determining whether the slip sheet is inserted. The inspection device <NUM> transmits the slip sheet insertion information (page m) to the printer <NUM> (step S204).

Based on the received slip sheet insertion information (page m), the job information generation unit <NUM> of the printer <NUM> determines the timing of inserting the slip sheet and generates job information (page m). For example, the timing of inserting the slip sheet may be a timing at which the slip sheet is inserted between page n and page n+<NUM>. Then, the printer <NUM> transmits the generated job information (page m) to the inspection device <NUM> (step S205).

Step S206 and step S207 illustrated in <FIG> are the same as step S103 and step S104, respectively, of the print process without slip sheet illustrated in <FIG>.

Further, steps S208 to S210 illustrated in <FIG> are the same as steps S107 to S109 of the print process without a slip sheet as illustrated in <FIG>.

At the timing of inserting a slip sheet (for example, between page n and page n+<NUM>), the job information processing unit <NUM> of the printer <NUM> executes ejection processing of the slip sheet (insertion of the slip sheet) from the sheet feeding tray set in advance, according to the job information (page m) (step S211). The ejection processing of the slip sheet may include processing of causing the printer <NUM> to print the slip sheet. In a case where the printer <NUM> is instructed to print the slip sheet, since the print job to print the slip sheet is not a job generated by the DFE <NUM>, the rasterized image of the slip sheet is not transmitted from the DFE <NUM> to the printer <NUM>. In this case, for example, in step S204, the slip sheet print information <NUM> for printing the slip sheet is sent from the inspection device <NUM> to the printer <NUM>. Note that the slip sheet print information <NUM> may be transmitted from the inspection device <NUM> to the printer <NUM> via the DFE <NUM>.

Steps S212 to S214 and step S215 illustrated in <FIG> are the same as steps S110 to S112 and step S116, respectively, of the print process without a slip sheet illustrated in <FIG>.

The reading unit <NUM> of the inspection device <NUM> acquires the read image data (page m) read by the first inline sensor <NUM> and the second inline sensor <NUM> (step S216). In the case of the job for slip sheet, the master image generation unit <NUM> of the inspection device <NUM> does not generate the master image data. The inspection device <NUM> associates the order of pages detected by the first inline sensor <NUM> and the second inline sensor <NUM> with the generated master image data according to the job information of each page including the page m and stores the associated information in the storage unit <NUM>.

When the read image data is based on a slip sheet job (page m), the inspection device <NUM> controls to display the read image data without performing the inspection process.

<FIG> is a flowchart of an example of the inspection process.

When the inspection process starts, the ejection control unit <NUM> acquires the defect determination information (step S301). The defect determination information is information generated by the defect determination unit <NUM> and includes the information of defect determination result per printed page, the sheet count value, and the minimum value of a slip sheet insertion interval.

The sheet count value is set to zero (<NUM>) when the power of the image forming apparatus <NUM> is turned on. The sheet count value is incremented by one each time the print sheet or the slip sheet is ejected to the stacker <NUM>. The minimum value of the slip sheet insertion interval is set in advance in response to an operation performed by a user on the operation panel <NUM> of the inspection device <NUM>.

The ejection control unit <NUM> determines the presence or absence of the defect with reference to the defect determination result included in the defect determination information (step S302). When it is determined that there is no defect (NO in step S302), the ejection control unit <NUM> ends the inspection process.

In step S303, when it is determined that there is a defect (YES in step S302), the ejection control unit <NUM> determines whether the slip sheet is inserted. Specifically, when the following Equation <NUM> is satisfied, the ejection control unit <NUM> determines that the slip sheet is allowed to be inserted.

However, when the sheet count value of the previously inserted slip sheet is zero (<NUM>), the ejection control unit <NUM> determines that the slip sheet is allowed to be inserted regardless of whether Equation <NUM> is satisfied or not.

That is, when it is determined that there is a defect in the printed sheet, the ejection control unit <NUM> determines that the slip sheet is allowed to be inserted in the following two cases. The first case is when the sheet count value (the number of output pages of the defective sheet) of the current sheet determined to be defective is larger than the sheet count value of the slip sheet (the number of output pages of the slip sheet) at the previous insertion of the slip sheet and is greater than a predetermined insertion interval. The second case is when the slip sheet has not been inserted yet.

The determination method is not limited to the above-described method. The following method may be employed as an alternative method. When it is determined that there is a defect in the image of the first conveyance medium, in a case where the first conveyance medium determined to be defective is ejected after the second conveyance medium is ejected and where the value of the slip sheet insertion interval is equal to or smaller than the set interval, the ejection control unit <NUM> does not eject the second conveyance medium even if the image of the first conveyance medium has a defect. On the other hand, when the value of the slip sheet insertion interval is greater than the set interval, the second conveyance medium is ejected when the ejection control unit <NUM> has determined that the first conveyance medium is defective. At this time, the display control unit <NUM> displays information of the defective first conveyance medium ejected after the second conveyance medium previously ejected, in association with information of the second conveyance medium to be currently ejected.

The sheet count value of the previously inserted slip sheet is stored in the control information storage unit <NUM> and is set to zero (<NUM>) when the power of the image forming apparatus <NUM> is turned on.

When the ejection control unit <NUM> determines that the slip sheet is not allowed to be inserted (NO in step S303), the ejection control unit <NUM> ends the inspection process. When the ejection control unit <NUM> determines that the slip sheet is not allowed to be inserted (YES in step S303), the ejection control unit <NUM> replaces the "sheet count value of the previously inserted slip sheet" stored in the control information storage unit <NUM> with the "sheet count value" and transmits the slip sheet insertion information (step S304).

Alternatively, when the slip sheet is not allowed to be inserted, the ejection control unit <NUM> may wait until suitable timing for inserting the slip sheet and then insert the slip sheet again. That is, the timing at which the slip sheet is inserted is indicated by interrupting again the print job in which the slip sheet is not allowed to be inserted. Due to the above-described configuration, the slip sheet is allowed to be inserted each time the defect is found.

<FIG> is a diagram illustrating an example of a slip sheet.

A user freely determines a pattern, design, quality of the slip sheet. However, in a case where a plurality of slip sheets is ejected, it is desirable that text or image for identifying the respective slip sheets is printed so as to know the positions of the respective slip sheets, and it is desirable that colors or patterns of the slip sheets are different from each other. Executing a process described below displays an image obtained by reading the slip sheet. By so doing, the correspondence between each slip sheet and a page in which a defect has been detected is recognized.

<FIG> is a diagram illustrating an example of a defect display screen. The display screen illustrated in <FIG> and the subsequent drawings are screens displayed on a display unit by the display control unit <NUM> transmitting screen information in response to a request received from the display unit such as an operation panel of an apparatus or a web browser of another apparatus. The display control unit <NUM> may display screen information on the display unit by bidirectional communication or push transmission.

A defect display screen <NUM> is a screen displayed on the operation panel <NUM> of the inspection device <NUM> in order to display the detected defects. The defect display screen <NUM> includes a "JOB LIST" display area <NUM>, a "DEFECT DETECTION PAGE LIST" display area <NUM>, and a "DEFECT DETECTION IMAGE" display area <NUM>.

<FIG> is a diagram illustrating an example of a job list.

The job list displayed in the "JOB LIST" display area <NUM> includes items "INSPECTION PROCESS START TIME", "NUMBER OF COPIES OF JOB", "NUMBER OF PAGES OF JOB", and "NUMBER OF DEFECT-DETECTED PAGES OF JOB". The job list may include identification information to identify the job, such as job names or job IDs, with which a plurality of jobs is confirmed and identified.

The value of the item "INSPECTION PROCESS START TIME" is a value indicating the start time of the inspection process of the first page of the job.

The value of the item "NUMBER OF COPIES OF JOB" is a value indicating the number of copies output in the job.

The value of the item "NUMBER OF PAGES OF JOB" is a value indicating the number of pages included in the job.

The value of the item "NUMBER OF DEFECT-DETECTED PAGES OF JOB" is a value indicating the number of pages with defects detected in the job.

<FIG> is a diagram illustrating an example of a defect detection page list.

The defect detection page list displayed in the "DEFECT DETECTION PAGE LIST" display area <NUM> includes items "DEFECT DETECTION TIME", "NUMBER OF DEFECTIVE COPIES OCCURRED IN JOB", "NUMBER OF DEFECTIVE PAGES OCCURRED IN JOB", "IMAGE DATA WITH DETECTED DEFECT", "IMAGE OF NEARBY SLIP SHEET", and "RELATION OF POSITIONS OF DEFECT DETECTED.

PAGE AND SLIP SHEET". That is, the display control unit <NUM> is configured to display the image of the slip sheet (second conveyance medium) in association with the information indicating the first conveyance medium determined that the image has a defect. As the information indicating the first conveyance medium on which the defective image is formed, a page having the defective image, a defect detection time, the number of copies having the detected defect, identification information of the page having the defective image, and the number of pages having the defective image may be displayed. As an image of the nearby slip sheet, an image that is acquired by the image acquisition unit such as an inline sensor and printed on a slip sheet to be ejected may be displayed. Further, when the image is printed on the slip sheet, an image data for printing may also be displayed. The display control unit <NUM> may display the image that is acquired by the image acquisition unit and printed on the slip sheet (second conveyance medium) to be ejected, in association with the information indicating the first conveyance medium determined that the image has a defect.

The value of the item "DEFECT DETECTION TIME" is a value indicating the time at which the defect was detected for each page.

The value of the item "NUMBER OF DEFECTIVE COPIES OCCURRED IN JOB" is a value indicating the number of copies where the defect has occurred.

The value of the item "NUMBER OF DEFECTIVE PAGES OCCURRED IN JOB" is a value indicating the number of pages where the defect has occurred.

In the display field of the value of the item "IMAGE DATA WITH DETECTED DEFECT", the read image data of the page having the defective image is displayed.

In the display field of the value of the item "IMAGE OF NEARBY SLIP SHEET", read image data obtained by reading the slip sheet stacked near the page having the defective image is displayed.

The value of the item "RELATION OF POSITIONS OF DEFECT DETECTED PAGE AND SLIP SHEET" is a value indicating the relation between the position of the printed page on which the defect is detected and the position at which the slip sheet is stacked. The relation of positions of the defect detected page and the slip sheet indicates the number of sheets that are sandwiched between the slip sheets and the defect detection face of the defect detected page (upper face or lower face). The relation of positions is displayed in association with information indicating a printed sheet (first conveyance medium) determined that the image has a defect. Note that the "DEFECT DETECTION PAGE LIST" display area <NUM> displaying the defect detection page list may further display identification information of the defective sheet such as the page ID or the sheet ID, or information included in the job information of <FIG> such as the job ID, in association with each defect detection sheet.

Note that the display control unit <NUM> uses the slip sheet that has already been printed to indicate the defect to display the defect of subsequent printing. Specifically, the display control unit <NUM> displays the relation of the positions of the defect detected page and the slip sheet already ejected not only for a first defect (first entry in <FIG>) that triggered the ejection of the slip sheet but also for a second defect (second entry in <FIG>) detected after the detection of the first defect. The relation of positions of the defect detected page and the slip sheet already ejected is displayed even the ejection control unit <NUM> determines that the slip sheet is not to be inserted at the time of the detection of the second defect (NO in step S303 in <FIG>).

As a result, the same image of the slip sheet is included in a plurality of entries (for example, the first entry and the second entry in <FIG>) in the defect detection page list. In other words, the display control unit <NUM> controls display of an image of one slip sheet (second conveyance medium) associating with information indicating a plurality of printed sheets (a plurality of first conveyance media) determined that the images have defects.

When correspondence between the slip sheet and the defect detection page is one-to-many, it is to determine which slip sheet corresponds to each defect detection page is used to display the relation of positions of the defect detection page and the slip sheet. Then, the display control unit <NUM> specifies the slip sheet stacked closest to the defect detection page. Specifically, the display control unit <NUM> calculates the number of sheets between the slip sheet stacked on the stacker <NUM> and the defect detection page based on the job information for the printed slip sheet received from the printer <NUM>, and then specifies the slip sheet having the smallest calculated number of sheets as the closest slip sheet. The read image data of the slip sheet specified in this manner is displayed as the value of the item "IMAGE OF NEARBY SLIP SHEET" of the defect detection page list. The process of specifying the slip sheet stacked closest to the defect detection page may be executed by the job information processing unit <NUM> of the inspection device <NUM>, the ejection control unit <NUM> of the inspection device <NUM>, or the printer <NUM>. The inspection device <NUM> may store the information of the specified slip sheet, and then the display control unit <NUM> may perform display control with reference to the stored information by the inspection device <NUM>. Further, the image serving as the image of the slip sheet may be an image obtained by reading the slip sheet or a thumbnail image created based on print image data of the slip sheet.

Note that the display control unit <NUM> serving as a web server provided in the inspection device <NUM> displays information indicating the first conveyance medium determined that the image has a defect, on a display unit such as a web browser installed in another apparatus or device. Further, in a case where the display unit does not display an image of the second conveyance medium corresponding to the first conveyance medium, the image of the second conveyance medium is acquired while the display unit is being displayed. In other words, the display unit continue displaying the information indicating the first conveyance medium determined to be defective, on the display unit while the image on the second conveyance medium is not displayed. Then, display control is performed to further display the acquired image of the second conveyance medium in association with the information indicating the first conveyance medium. At this time, the web server (display control unit <NUM>) of the inspection device <NUM> sends and displays screen information that includes information indicating the first conveyance medium determined that the image has a defect. When the image of the second conveyance medium is acquired, display control is performed to further display the acquired image of the second conveyance medium in association with the information indicating the first conveyance medium while the acquired image of the second conveyance medium is displayed on the web browser.

<FIG> is a diagram illustrating an example of a defect detection image.

The "DEFECT DETECTION IMAGE" display area <NUM> in <FIG> displays read image data of a printed page designated in the defect detection page list illustrated in <FIG> to which a display <NUM> indicating the defect detection portion is added.

<FIG> is a diagram illustrating an example of a setting screen of the insertion interval of the slip sheet.

A setting screen <NUM> is a screen for setting the slip sheet insertion interval. The display control unit <NUM> of the inspection device <NUM> displays information on the setting screen <NUM>. The number of printed sheets to be output is input as the slip sheet insertion interval via the setting screen <NUM>. The storage unit <NUM> stores the information indicating the slip sheet insertion interval in response to receipt of the information. Since the setting is received, the printer <NUM> does not eject the slip sheet even if the defect is detected during the slip sheet insertion interval after the previous slip sheet is ejected. Note that the insertion interval of the slip sheet may be set based on the number of outputs (printed sheets), an output time (period), or the number of jobs.

<FIG> is a diagram illustrating an example of a setting screen of the slip sheet feeding tray.

A setting screen <NUM> for slip sheet insertion tray is a screen for selecting a tray from which a slip sheet is to be fed. A tray set in advance is selected. The initial value of the displayed option may be a tray included in the insertion device <NUM>. In response to receipt of the setting of a tray, the storage unit <NUM> stores information indicating the set tray. Then, the inspection device <NUM> transmits the slip sheet insertion information that includes the information indicating the set tray to the printer <NUM>.

Note that the setting screen <NUM> may be displayed, for example, on the operation panel <NUM> by the control of the printer <NUM>. In this case, the slip sheet insertion information does not include information indicating the slip sheet feeding tray. The printer <NUM> stores information indicating the tray set in the storage unit <NUM>. Then, when the printer <NUM> execute a job for inserting a slip sheet, the printer <NUM> selects a sheet feed source tray based on the information indicating the slip sheet feeding tray.

The image forming system <NUM> according to the present embodiment reads and displays an image of a slip sheet to be ejected. Due to this configuration, the appearance of the slip sheet is recognized. As a result, a user finds the slip sheet more easily. In addition, the image forming system <NUM> reads and displays an image each time a slip sheet is ejected. By so doing, even when there is a difference in the appearance of a plurality of slip sheets, the appearance of each slip sheet is easily recognizable. As a result, a user can easily find each slip sheet.

Further, since the relation of the positions of the defect detected page and the slip sheet is displayed on the operation panel as the value of the item "RELATION OF POSITIONS OF DEFECT DETECTED PAGE AND SLIP SHEET" of the defect detection page list, the user is prompted to find the defect detected sheet by counting the number of sheets from the slip sheet found by the user. Since the number of sheets between the slip sheet and the defective sheet is relatively small in general, it is not difficult to count the number of sheets.

As described above, the image forming system <NUM> of the present embodiment prompts the user to find respective slip sheet and also to find the defective first conveyance medium.

Next, descriptions are given of an image forming system <NUM> according to a second embodiment of the present disclosure, with reference to the drawings. The configuration of the image forming system <NUM> according to the second embodiment is basically similar to the configuration of the image forming system <NUM> according to the first embodiment. Different from the first embodiment, the configuration of the image forming system <NUM> according to the second embodiment includes a function to determine whether job information of a slip sheet or read image data of a slip sheet has been acquired. Thus, in the following description of the second embodiment, differences from the first embodiment are mainly described. The components of the second embodiment having the same functional configurations as the components of the first embodiment are denoted by the same reference numerals used in the description of the first embodiment, and descriptions of the components similar to the first embodiment are omitted in the second embodiment.

The display control unit <NUM> of the inspection device <NUM> determines whether the job information of the slip sheet and the read image data of the slip sheet are acquired, and then determines an item so that the value of the item is to be displayed in the defect detection page list according to the determination result.

The following descriptions are given of operations of the image forming system <NUM> according to the second embodiment of the present disclosure.

<FIG> is a flowchart of a display control process, according to the second embodiment of the present disclosure.

The display control process described in <FIG> is a control for determining contents to be displayed on the defect detection page list. Specifically, the inspection device <NUM> receives a selection from the job list on the defect display screen illustrated in <FIG> (step S401). The display control unit <NUM> determines whether the selected job includes a defective image (step S402).

When the display control unit <NUM> determines the selected job does not include a defective image (NO in step S402), the display control unit <NUM> ends the display control process. In this case, the value of the defect detection page list is not displayed.

When the display control unit <NUM> determines the selected job includes a defective image (YES in step S402), the display control unit <NUM> displays the defect detection time, the number of copies having the detected defect, the number of pages having the detected defect, and the read image data of the image having the detected defect (step S403).

When there is a plurality of detected defects, the display control unit <NUM> executes processing from step S403 to step S405 for each defect.

Next, the display control unit <NUM> determines whether job information of a slip sheet and read image data of the slip sheet have been acquired (step S404). In a case where the job information of the slip sheet is acquired, the display control unit <NUM> specifies a nearby slip sheet as the slip sheet to be displayed in association with each defect. Specifically, the display control unit <NUM> calculates the number of sheets between the slip sheet stacked on the stacker <NUM> and the defect detection page, and then specifies the slip sheet having the smallest calculated number of sheets as the closest slip sheet. Then, the display control unit <NUM> determines whether the read image data of the slip sheet specified as the nearby slip sheet has been acquired.

When the display control unit <NUM> determines that the job information of the slip sheet and the read image data of the slip sheet are acquired (YES in step S404), the display control unit <NUM> displays the read image information of the slip sheet (the item "IMAGE OF NEARBY SLIP SHEET") and the relation between the positions of the ejected slip sheet and the defective sheet is stacked (the item "RELATION OF POSITIONS OF DEFECT DETECTED PAGE AND SLIP SHEET") (step S405). In other words, the display control unit <NUM> is configured to display information indicating a relation of stacking positions between the first conveyance medium and the second conveyance medium that is ejected, in association with the information indicating the first conveyance medium.

When the display control unit <NUM> determines that either the job information of the slip sheet or the read image of the slip sheet has not been acquired (NO in step S404), the display control unit <NUM> skips the processing of step S405. When the processing of step S405 is skipped and the read image data of the slip sheet is acquired later, the slip sheet information including the read image data of the slip sheet and the information of relation position are collectively displayed in association with each skipped defect information (information of the first conveyance medium having a defect) by the processing of step S405.

The display control unit <NUM> determines whether another defective image is detected (step S406). When the display control unit <NUM> determines that another defective image is detected (YES in step S406), the display control unit <NUM> returns to the processing of step S403 and executes processing for the newly detected defective image.

When the display control unit <NUM> determines that another defective image is not detected (NO in step S406), the display control unit <NUM> ends the process.

<FIG> is a diagram illustrating a result of display control, according to the second embodiment of the present disclosure.

The defect detection page list 909a indicates a defect detection page list displayed immediately after it is determined that a page has a defect. Immediately after it is determined that a page has a defect, the inspection device <NUM> has not acquired job information of a slip sheet or read image data of a slip sheet. Therefore, in step S404 of the flowchart in <FIG>, the display control unit <NUM> determines that either the job information of the slip sheet or the read image data of the slip sheet has not been acquired. As a result, the display fields of the values of the items "IMAGE OF NEARBY SLIP SHEET" and "RELATION OF POSITIONS OF DEFECT DETECTED PAGE AND SLIP SHEET" become blank.

The defect detection page list 909b indicates a defect detection page list displayed after the inspection device <NUM> had acquired the job information of the slip sheet and the read image data of the slip sheet. In this case, in step S404 of the flowchart in <FIG>, the display control unit <NUM> determines that the job information of the slip sheet and the read image data of the slip sheet are acquired. Accordingly, the read image data of the slip sheet and the relation between the position of the ejected slip sheet and the position at which the sheet having a detected defect is stacked are displayed respectively in the display fields of the values of the items "IMAGE OF NEARBY SLIP SHEET" and "RELATION OF POSITIONS OF DEFECT DETECTED PAGE AND SLIP SHEET".

It is assumed that it takes time to complete the processing of reading the image of the slip sheet after it is determined that a page has a defect. When the defect detection page list is displayed after the value of each item to be displayed is determined, it takes time to display the presence or absence of a defect. On the other hand, according to the image forming system <NUM> of the present embodiment, the inspection device <NUM> determines the item for displaying the value according to the timing of acquiring the job information of the slip sheet and the read image data of the slip sheet. Therefore, the information indicating the presence of the defect is displayed immediate after the defect is detected.

Although <FIG> illustrates an example in which the defect detection page list is displayed so that rows are added downward in the order of detection, the defect detection page list may be displayed so that rows are added upward in the order of detection in accordance with images stacked on the stacker <NUM>.

The reading unit <NUM> may read characters on the slip sheet by character recognition using optical character recognition (OCR). In other words, read characters are text information acquired by character recognition. In this case, the display control unit <NUM> may control display by adding an item such as "NEARBY SLIP SHEET TEXT" to the defect detection page list illustrated in <FIG>. Text is acquired by performing character recognition processing on read image data obtained by reading a slip sheet stacked near a page in which a defect has been detected. The acquired text is then displayed in the value display field of the item "NEARBY SLIP SHEET TEXT" as illustrated in <FIG>. As a result, a user is prompted to distinguish respective slip sheets from each other more easily.

According to the image forming system <NUM> of the present embodiment, the slip sheet that has already been printed to indicate the defect is used to display the defect in subsequent printing. Due to the above-described configuration, a plurality of defective portions is displayed with one slip sheet, and even when the plurality of defects occurs, the number of slip sheets to be inserted is determined appropriately.

Each of the above-described embodiments describes the example in which an image is not printed on a slip sheet and the slip sheet is simply ejected. As a result, the print process of the slip sheet is omitted, and the toner is not consumed. On the other hand, an image may be printed on a slip sheet. As a result, generating a slip sheet with an outstanding color tone using inexpensive sheets is achieved, configuration changes such as changes in color patterns is flexibly achieved, and saving the effort of separately preparing sheets for the slip sheet.

In each of the above-described embodiments, the DFE <NUM>, the inspection device <NUM> and the printer <NUM> are configured to share the above-described processing steps in various combinations. Further, the elements of the DFE <NUM>, the inspection device <NUM> and the printer <NUM> may be integrated into one apparatus or may be separately disposed in a plurality of different apparatuses.

For example, the above-described embodiments describe the examples in which the inspection device <NUM> generates the slip sheet insertion information and the printer <NUM> generates job data for the slip sheet based on the slip sheet insertion information. As a result, the inspection device <NUM> reduces the load of processing other than inspection and avoids a delay in the speed of inspection. However, the inspection device <NUM> may generate job data for the slip sheet and transmit the job data to the printer <NUM>. Due to the above-described configuration, the printer <NUM> does not include a special mechanism for printing on a slip sheet, thus a system is easily introduced.

In an embodiment, the DFE <NUM> or the inspection device <NUM> may be configured as an information processing system including a plurality of computing devices such as a server cluster. The plurality of computing devices is configured to communicate with one another via any type of communication link, including a network or shared memory to implement the processing described in the present invention. For example, a web server function including a display control unit provided in a device such as the inspection device <NUM>, the DFE <NUM>, or the printer <NUM> may be provided in an information processing apparatus in the cloud. Then, device information including a defect inspection result collected from each device, an acquired image data of a slip sheet, or job information may be uploaded to the information processing apparatus in the cloud as appropriate. In addition, the uploaded information may be displayed as a list or automatically updated using bidirectional communication, by acquiring device information via the Internet using software such as a web browser of device or various devices.

Each of the functions of the described embodiments may be implemented by one or more processing circuits or circuitry. Processing circuitry includes a programmed processor, as a processor includes circuitry. A processing circuit also includes devices such as an application specific integrated circuit (ASIC), a digital signal processor (DSP), a field programmable gate array (FPGA), and conventional circuit components arranged to perform the recited functions.

In the above-described embodiments, the stacker <NUM> includes one sheet ejection tray <NUM>. However, in other embodiments, the stacker <NUM> may include the plurality of sheet ejection trays <NUM>. For example, the stackers <NUM> and the sheet ejection trays <NUM> illustrated in <FIG> are configured to receive and stack ejected printed sheets and ejected slip sheets and are examples of the ejection device according to the present disclosure. In the ejection and stacking method illustrated in <FIG>, printed sheets and slip sheets are collectively ejected onto one sheet ejection tray <NUM>. Thus, even in the ejection, a plurality of printed sheets having defects and the plurality of slip sheets are easily distinguished from each other.

Further, when the sheets are collectively ejected to one sheet ejection tray, the plurality of printed sheets having defects are included across the plurality of jobs or a plurality of copies of the same job which are continuously ejected. However, the user easily grasps the position of the defective sheet by ejecting the plurality of slip sheets that is distinguished from each other even if a relatively large number of sheets is ejected. Further, as illustrated in <FIG>, the slip sheets and the printed sheets may be separately ejected to the plurality of sheet ejection trays <NUM>. Further, for example, as illustrated in <FIG>, the slip sheet ejected to the upper sheet ejection tray <NUM> may indicate that the image that has the defect in the printed sheets of the lower sheet ejection tray <NUM>.

Further, in a case where sheets are ejected to the plurality of sheet ejection trays <NUM>, the sheets are ejected separately to the sheet ejection trays <NUM> for each print job. In this case, as illustrated in FIG. <NUM>, when the slip sheet is ejected to the uppermost position of the sheet ejection trays <NUM>, the slip sheet is not overlaid by the upper printed sheets, and the visibility of the slip sheet is enhanced, so that the slip sheet is more easily found. In this case, when the slip sheet is not ejected at the uppermost position (the lowermost sheet ejection tray <NUM> in <FIG>), the user finds that no defective sheet has been detected in the print job, thereby enhancing the workability.

In addition, as illustrated in <FIG>, in the case where sheets are separately ejected to the plurality of sheet ejection trays <NUM>, the display control unit <NUM> may display identification information (tray A, tray B) of the ejected sheet ejection tray <NUM> or the level of sheet ejection tray (the first tray from the top, the second tray from the top) for each cover of printed sheets with defects. This configuration indicates the sheet ejection tray <NUM> to which each of the defective sheet and the slip sheet is ejected.

The above-described embodiments are illustrative and do not limit the present invention. Thus, numerous additional modifications and variations are possible in light of the above teachings. For example, elements and/or features of different illustrative embodiments may be combined with each other and/or substituted for each other within the scope of the present invention.

Claim 1:
An inspection device (<NUM>) comprising:
an image acquisition unit (<NUM>, <NUM>, <NUM>) configured to acquire an image formed on a first conveyance medium;
a defect determination unit (<NUM>) configured to determine whether the image on the first conveyance medium is defective, based on the image acquired by the image acquisition unit (<NUM>, <NUM>, <NUM>);
an ejection control unit (<NUM>) configured to control to eject a second conveyance medium in a case where the image on the first conveyance medium is defective; and
a display control unit (<NUM>),
characterized in that the display control unit (<NUM>) is configured to control to display an image formed on the second conveyance medium in association with information indicating the first conveyance medium determined to be defective.