Printing system, inspection method and media

Abstract

Provided are a printing system, an inspection method, and a medium. The system comprises: a printing unit (101) for forming an image on a sheet conveyed along a conveying path; an inspection unit (106, 108) for inspecting the image formed on the sheet conveyed along the conveying path by comparing the image with a reference image, and for recording sequence information of inspected sheets and sequence information of correctly discharged sheets; and a control unit for controlling the inspection unit to restart inspection from the beginning sheet recorded as not inspected or not correctly discharged after printing is restarted, if a paper jam occurs in the conveying path of the sheet.

Description

Technical Field

[0001] The present invention relates to a printing system, an inspection method and a medium for inspecting the quality of printed articles. Background Art

[0002] An inspection device is known that reads a printed article printed by a printing device and inspects the quality of the printed article. The inspection device can detect image defects such as smudges and missing prints, text errors, and barcode quality, etc. Finished products for which such defects are detected are separated from non-defective printed articles by, for example, changing the discharge destination.

[0003] In the case where a sheet being conveyed is checked by an inspection unit provided in a sheet conveying path for conveying the sheet, a sheet jam may occur in the sheet conveying path downstream (hereinafter referred to as "downstream side") from the inspection unit in the sheet conveying direction. In this case, the sheet that is correctly inspected is determined by the inspection device to be the jammed paper. Since the image printed on the jammed paper is printed again through the jam recovery process, the inspection using the inspection device is also performed again. Depending on the position of the jam, a sheet with the same print content may be inspected twice, which results in the inspection being performed using a reference image in a misaligned state and a captured image, and the sheet is judged to be defective. There is a problem that, in the event of a jam, the user needs to confirm the removed jammed paper and the image on the last sheet on the discharge tray to determine whether it is necessary to set a re-inspection start page for the sheet inspection device, and this complicates the jam handling operation.

[0004] In order to avoid such a problem, it is conceivable to wait for an instruction from the user and start the paper jam recovery process based on the instruction from the user, rather than automatically starting the paper jam recovery process after the jammed paper is removed. For example, a technology has been disclosed in which a setting screen for rechecking the start page is displayed only when it is necessary to set the recheck start page, and printing is restarted in response to a restart instruction from the user (Japanese Patent Laid-Open No. 2018-31963). Summary of the invention

[0005] However, in this prior art, after removing the jammed paper, the user needs to manually identify and input the recheck start page. Therefore, there is a problem that restarting the check process in the event of a paper jam is troublesome.

[0006] The present invention enables the inspection device to identify the inspection recovery start page by considering not only the paper jam occurrence information but also the paper conveyance information in the judgment condition.

[0007] The present invention has the following structure.

[0008] The present invention provides a printing system in its first aspect, comprising: a printing component (101) configured to form an image on a sheet conveyed along a conveying path; an inspection component (106, 108) configured to inspect the image formed on the sheet conveyed along the conveying path by comparing the image with a reference image, and record sequence information of the inspected sheets and sequence information of the correctly discharged sheets; and a control component (216, 226) configured to control the inspection component (106, 108) to restart the inspection from the beginning sheet recorded as not yet inspected or not yet correctly discharged after printing is restarted in the event of a paper jam in the sheet conveying path.

[0009] The present invention, in its second aspect, provides an inspection method for inspecting an image formed on a sheet conveyed along a conveying path, the inspection method comprising: inspecting the image formed on the sheet conveyed along the conveying path by comparing the image with a reference image; recording sequence information of inspected sheets and sequence information of correctly discharged sheets; and in the event of a paper jam in the conveying path of the sheet, after printing is restarted, restarting the inspection from the beginning sheet recorded as not yet inspected or not yet correctly discharged.

[0010] The present invention, in its third aspect, provides a computer-readable medium storing a program which, when executed by a computer, causes the computer to execute a checking method for checking an image formed on a sheet conveyed along a conveying path, the checking method comprising: checking the image formed on the sheet conveyed along the conveying path by comparing the image with a reference image; recording sequence information of the sheets that have been checked and sequence information of the sheets that have been correctly discharged; and in the event of a paper jam in the conveying path of the sheet, after printing is restarted, restarting the checking from the beginning sheet that is recorded as not having been checked or not having been correctly discharged.

[0011] According to the present invention, the inspection device can identify the inspection recovery start page, and the user can restart printing without having to set the start page to be used when the inspection is restarted. This makes it possible to eliminate the problem that restarting the inspection process is troublesome in the event of a paper jam, and to improve the productivity of the printing operation.

[0012] Further features of the present invention will become apparent from the following description of embodiments with reference to the attached drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 is a schematic diagram showing the configuration of an information processing apparatus, an inspection apparatus, and a printing apparatus according to the embodiment.

[0014] Figure 2is a block diagram showing the configuration of an information processing apparatus, an inspection apparatus, and a printing apparatus according to the embodiment.

[0015] Figure 3 : is a diagram showing the internal structure of an information processing apparatus, an inspection unit, a printing apparatus, and a large-volume stacker according to the embodiment.

[0016] Figure 4 is a flowchart showing the basic operation of the inspection device according to the embodiment.

[0017] Figure 5 is a flowchart illustrating basic operations of a printing device and an inspection unit during inspection according to the embodiment.

[0018] Figure 6 is a flowchart showing the basic operation of the inspection device according to the first embodiment.

[0019] Figure 7 is a flowchart showing basic operations of the printing device and the inspection unit during inspection according to the first and second embodiments.

[0020] Figure 8 : is a diagram showing an example of a check restart page management table according to the first embodiment.

[0021] Fig.9A is a timing chart for the inspection apparatus and the inspection unit according to the first embodiment.

[0022] Fig. 9B is a timing chart for the inspection apparatus and the inspection unit according to the first embodiment.

[0023] Fig.10 is a flowchart showing the basic operation of the inspection device according to the second embodiment.

[0024] Fig.11 is a timing chart for the inspection apparatus and the inspection unit according to the second embodiment.

[0025] Fig.12 is a flowchart showing the basic operation of the inspection apparatus according to the third and fourth embodiments.

[0026] Fig.13 is a flowchart showing basic operations of the printing apparatus and the inspection unit during inspection according to the third embodiment.

[0027] Fig.14A is a timing chart for the inspection apparatus and the inspection unit according to the third embodiment.

[0028] Fig. 14B is a timing chart for the inspection apparatus and the inspection unit according to the third embodiment.

[0029] Fig.15 is a flowchart showing basic operations of the printing apparatus and the inspection unit during inspection according to the fourth embodiment.

[0030] Fig.16A is a timing chart for the inspection apparatus and the inspection unit according to the fourth embodiment.

[0031] Fig. 16B is a timing chart for the inspection apparatus and the inspection unit according to the fourth embodiment. DETAILED DESCRIPTION

[0032] Hereinafter, the embodiments will be described in detail with reference to the accompanying drawings. Note that the following embodiments are not intended to limit the scope of the claimed invention. A plurality of features are described in the embodiments, but are not limited to the invention requiring all of these features, and a plurality of such features may be appropriately combined. In addition, in the accompanying drawings, the same reference numerals are given to the same or similar structures, and redundant descriptions thereof are omitted.

[0033] It goes without saying that, unless otherwise specified, the present invention can be applied to an inspection device that is an independent device or is composed of a plurality of devices, as long as the functions according to the present invention are implemented. If the functions of the present invention are implemented, the present invention can also be applied to an inspection device that is connected to a network such as a LAN (local area network) or a WAN (wide area network) and processes through a network such as a LAN (local area network) or a WAN (wide area network). In other words, the system structure connecting the various types of terminals described in the following embodiments is only an example, and it goes without saying that various structural examples are possible depending on the application and purpose, etc. Before describing the various embodiments, the structure and sequence, etc. common to all embodiments will be described.

[0034] Equipment structure

[0035] Figure 1 1 is a schematic diagram showing an image forming system (also referred to as a printed article inspection system) composed of an information processing device, an inspection device, and a printing device according to the present embodiment. Although the printing device according to the present embodiment is described using an electrophotographic printing device, the printing device according to the present embodiment may be a printing device using a different image forming method such as an inkjet method or an offset printing method.

[0036] The printing apparatus 101 (printing means) is connected to the information processing apparatus 109 via a cable 111. The information processing apparatus 109 is connected to a client computer 110 and an inspection apparatus (inspection execution means) 108 via a network 112.

[0037] The printing device 101 includes a user interface (UI) panel 102, a paper feed stage 103, and a paper feed stage 104. An optional stage 105 consisting of three paper feed stages is also connected. The printing device 101 is, for example, an electrophotographic printing device. The UI panel 102 is a user interface including, for example, a capacitive touch panel.

[0038] The printing device 101 also includes an inspection unit (obtaining component) 106 and a large-capacity stacker 107. The inspection unit 106 is connected to the inspection device 108 via a cable 113, and the inspection unit 106 and the inspection device 108 together include an image inspection component. The large-capacity stacker 107 includes a main tray and a top tray, and the main tray is capable of holding a stack of several thousand sheets of paper at a time. Note that in this embodiment, the term "sheet" can be considered to have the same meaning as "paper". The inspection device 108 and the inspection unit 106 can also be collectively referred to as an "inspection device". In this example, the inspection unit 106 uses a scanner to obtain an image formed on a sheet. The inspection device 108 corresponds to an inspection execution unit that inspects an image based on the obtained image and a reference image.

[0039] A print job is generated by the client computer 110, sent to the information processing apparatus 109 via the network 112, and managed by the information processing apparatus 109. Then, the print job is sent from the information processing apparatus 109 to the printing apparatus 101 via the cable 111, and the printing apparatus 101 performs processing for printing onto paper.

[0040] Note that the client computer 110, the information processing apparatus 109, and the inspection apparatus 108 can be connected to the cable 111 and can communicate with the printing apparatus 101. In other words, the connection form of the printing apparatus 101, the information processing apparatus 109, and the client computer 110 described in the present embodiment is merely an example, and it goes without saying that various connection forms other than the connection form described in the present embodiment are possible.

[0041] Figure 2 1 is a block diagram showing a control structure of the printing apparatus 101 , the checking unit 106 , the checking apparatus 108 , the large-volume stacker 107 , the information processing apparatus 109 , and the client computer 110 according to the present embodiment.

[0042] In the printing apparatus 101, a CPU (Central Processing Unit) 201 controls each unit within the printing apparatus 101 and performs calculations via a system bus 212. The CPU 201 processes the execution of programs stored in a storage unit 205 and loaded into a RAM (Random Access Memory) 202. The RAM 202 is a typical type of volatile storage device that can be directly accessed by the CPU 201, and is used as a work area or other temporary data storage area for the CPU 201. The storage unit 205 is used as a temporary storage area and a work memory when the printing apparatus operates.

[0043] The engine I / F 209 communicates with the printer engine 210 and controls the printer engine 210. The paper supply deck I / F 204 communicates with the paper supply deck 211 and controls the paper supply deck 211. The "paper supply deck 211" is a general term for the paper supply decks 103 and 104 and the optional deck 105 as a hardware structure. The UI panel 203 is a hardware structure of the UI panel 102, and is a user interface for performing overall operations of the printing apparatus 101. This embodiment assumes that the UI panel 203 is a capacitive touch panel.

[0044] A network interface (hereinafter "NW I / F") 207 is connected to an NW I / F 238 of the information processing device 109 via a cable 213, and processes communication between the information processing device 109 and the printing device 101. Although this example describes the interfaces connected to the system buses 212 and 239 as being directly connected to each other, the information processing device 109 and the printing device 101 may be connected, for example, via a network, and the connection form is not limited. The video I / F 206 is connected to the video I / F 233 via a video cable 241, and processes image data communication between the information processing device 109 and the printing device 101.

[0045] Note that the connection interface in the information processing apparatus 109 with the printing apparatus 101 may be a form in which the functions of the NW I / F 238 and the video I / F 233 are integrated. Similarly, the connection interface in the printing apparatus 101 with the information processing apparatus 109 may be a form in which the functions of the NW I / F 207 and the video I / F 206 are integrated.

[0046] The accessory I / F 208 is connected to the accessory I / F 214 and the accessory I / F 220 through a cable 225. In other words, the printing apparatus 101 communicates with the checking unit 106 and the large-volume stacker 107 via the accessory I / Fs 208, 214, and 220.

[0047] In the inspection unit 106, the CPU 216 controls the various units within the inspection unit 106 and performs calculations via the system bus 219, and processes the execution of the program stored in the storage unit 247 and loaded into the RAM 217. The RAM 217 is a typical type of volatile storage device that can be directly accessed by the CPU 216, and is used as a work area or other temporary data storage area for the CPU 216. The storage unit 247 is used as a temporary storage area and working memory when the inspection device operates. The inspection device I / F 215 is connected to the inspection unit I / F 231 through the cable 248. In other words, the inspection unit 106 communicates with the inspection device 108 via the inspection device I / F 215 and the inspection unit I / F 231.

[0048] The imaging unit 218 has an imaging function using a contact image sensor (hereinafter referred to as "CIS"), for example, captures an image of paper passing through the inspection unit, and transmits the captured image to the inspection device 108 via the inspection device I / F 215. Note that the CIS is only one example of a sensor used for the imaging unit 218. Other types of sensors such as a CCD image sensor may be used, and the imaging method is not limited.

[0049] In the large-capacity stacker 107, the CPU 221 controls the various units within the large-capacity stacker 107 via the system bus 224 and performs calculations, and processes the execution of the programs stored in the storage unit 248 and loaded into the RAM 222. The RAM 222 is a typical type of volatile storage device that can be directly accessed by the CPU 221, and is used as a work area or other temporary data storage area for the CPU 221. The storage unit 248 is used as a temporary storage area and a working memory when the inspection device operates. The paper discharge unit 223 processes the operation for discharging paper to the main tray and the top tray, and the monitoring and control of the loading status of the main tray and the top tray, etc.

[0050] In the inspection device 108, the CPU 226 controls the various units within the inspection device 108 via the system bus 230 and performs calculations, and processes the execution of the programs stored in the storage unit 228 and loaded into the RAM 227. The RAM 227 is a typical type of volatile storage device that can be directly accessed by the CPU 226, and is used as a work area or other temporary data storage area for the CPU 226. The storage unit 228 is used as a temporary storage area and working memory when the inspection device operates. The PDL analysis unit 229 performs processing for reading and analyzing PDL data such as PDF, PostScript, or PCL received from, for example, the client computer 110 or the information processing device 109. The display unit 245 is, for example, a liquid crystal display connected to the inspection device, and accepts user input made to the inspection device, displays the status of the inspection device, and the like.

[0051] In the information processing device 109, the CPU 234 controls and calculates each unit within the information processing device 109 via the system bus 239, and processes the execution of the program stored in the storage unit 236 and loaded into the RAM 235. The RAM 235 is a typical type of volatile storage device that can be directly accessed by the CPU 234, and is used as a work area or other temporary data storage area for the CPU 234. The storage unit 236 is used as a temporary storage area and working memory when the information processing device operates. The network interface (hereinafter referred to as "NW I / F") 237 is connected to the NW I / F 240 through the network. The information processing device 109 communicates with the inspection device 108 via the NW I / F 237 and the NW I / F 232. In addition, the information processing device 109 is connected to the client computer 110 via the NWI / F 237 and the NW I / F 240.

[0052] In the client computer 110, the CPU 243 controls various units within the client computer 110 and performs calculations via the system bus 246, and processes the execution of programs stored in the storage unit 244 and loaded into the RAM 242. The RAM 242 is a typical type of volatile storage device that can be directly accessed by the CPU 243, and is used as a work area or other temporary data storage area for the CPU 243. The storage unit 244 is used as a temporary storage area and a working memory when the client computer operates.

[0053] Internal structure of the printing system

[0054] Figure 3101, the inspection unit 106, and the large-capacity stacker 107. The printing apparatus 101 accepts user input and displays printing and apparatus status, etc. through the UI panel 102. Various types of paper can be held in the paper feed tables 103 and 104. In each paper feed table, only the uppermost sheet of the held paper can be separated and conveyed to the paper conveying path 305.

[0055] The developing stations 301 to 304 form toner images using Y, M, C, and K color toners, respectively, so as to form a color image. The toner images formed here undergo primary transfer to the intermediate transfer belt 306. The intermediate transfer belt 306 is moved along the Figure 3 , and the toner image is transferred to the paper conveyed from the paper conveying path 305 at a secondary transfer position indicated by 307. The fixing unit 308 includes a pressure roller and a heating roller, and fixes the toner image to the paper by melting and compressing the toner when the paper passes between the rollers.

[0056] The paper leaving the fixing unit 308 is conveyed to 312 through a paper conveying path 309. If further melting and pressure are required for fixing due to the type of paper, the paper having passed through the fixing unit 308 is conveyed to a second fixing unit 310 using the above-mentioned paper conveying path; and after additional melting and pressure are applied, the paper is conveyed to 312 through a paper conveying path 311. If the image forming mode is duplex, the paper is conveyed to a paper reversing path 313, and after being reversed in the paper reversing path 313, the paper is conveyed to a duplex conveying path 314, where image transfer of the second side is performed at a secondary transfer position 307.

[0057] CIS 315 and 316 are provided opposite to each other in the inspection unit 106. CIS 315 is a sensor for reading the upper surface of paper, and CIS 316 is a sensor for reading the lower surface of paper. The inspection unit 106 scans the paper at the timing when the paper conveyed in the paper conveying path 317 reaches a predetermined position using CIS 315 and 316. The scanned image is sent to the inspection device 108 via the inspection device I / F 215 and the inspection unit I / F 231. The CPU 226 of the inspection device 108 determines whether there is a defect in the received image, and notifies the inspection unit 106 of the determination result again via the inspection unit I / F 231 and the inspection device I / F 215. The CPU 216 notifies the large-volume stacker 107 of the received determination result via the accessory I / Fs 214 and 220. The inspection device 108 holds a reference image corresponding to a sheet, and inspects the print quality by comparing the image captured by the inspection unit 106 with the reference image. At this time, for example, when a single document is printed in units of copies, the content printed on each sheet in each copy is different. Therefore, the checking device 108 changes the reference image as printing proceeds. If the job is a job that prints in page order (sheet order), the corresponding reference image is also switched.

[0058] The large-capacity stacker 107 is capable of holding a large amount of paper. The large-capacity stacker 107 includes a main tray 324 used as a tray for stacking paper. Paper that has passed the inspection unit 106 enters the large-capacity stacker 107 via a paper conveying path 319. Paper is stacked in the main tray 324 via a sheet conveying path 322 from the paper conveying path 319. The large-capacity stacker 107 also includes a top tray 320 used as a discharge tray. The CPU 221 controls the paper conveying path to discharge paper for which a defect is detected by the inspection device 108 to the top tray 320. When being output to the top tray 320, the paper is conveyed from the paper conveying path 319 to the top tray 320 through the paper conveying path 321. When paper is loaded on the main tray 324, a reversing unit 323 for reversing the sheet is used. In order to ensure that the paper feeding direction is the same as the direction of the paper when the paper is loaded, when the paper is loaded in the main tray 324, the paper is reversed once by the reversing unit 323. When the paper is conveyed to the top tray 320 , the sheet is discharged as it is during loading, ie, does not need to be turned over, and thus the reversing unit 323 does not perform a reversing operation.

[0059] Check the treatment performed by the device

[0060] Figure 4 is a flow chart showing the basic operations performed by the inspection device 108 during an inspection.

[0061] In step S401, the CPU 226 accepts an image reading start instruction from the user through the display unit 245. Then, the sequence moves to step S402, and in step S402, if there is a sheet to be inspected, the sequence moves to step S403. Step S402 indicates that the steps from S402 to S412 are repeated and the conditions for the repetition. In step S402, the condition is that there is an uninspected sheet to be inspected.

[0062] In step S403, the inspection unit I / F 231 receives the image scanned by the CIS 315 and the CIS 316 from the inspection device I / F 215. Then, in step S404, the CPU 226 compares the reference image stored in the RAM 227 with the scanned image to be inspected received in step S403. It is assumed that before the start of this process, the reference image is sent to the inspection unit I / F 231 from the inspection device I / F 215 by scanning the paper printed by the printing device 101 using the CIS 315 and 316, and is stored in the RAM 227. In this comparison operation, first, the image positions of the reference image and the scanned image to be inspected are aligned using the feature points of the image as reference points for alignment. Next, in the scanned image to be inspected, the four corners of the paper and the reference points for alignment of the scanned image are analyzed, and it is detected whether there is any misalignment of the image relative to the paper. Next, the density values ​​of the reference image and the scanned image to be inspected are compared in units of pixels. If no defect is detected as a result of the above-mentioned processing, the inspection result is "accepted".

[0063] Next, in step S405, if the inspection result is "OK", the sequence moves to step S406, in which the inspection unit I / F 231 indicates to the inspection device I / F 215 that the inspection result is "OK", that is, the sheet will be discharged to the main tray 324 of the large-capacity stacker 107. Then, the sequence moves to steps S408 to S412, and the processing of steps S402 to S412 is repeated until the inspection is completed for all sheets. Once the inspection is completed for all sheets, the sequence moves to step S413, in which the CPU 226 accepts an instruction from the user to end reading the image through the display unit 245.

[0064] If the check result is "failed" in step S405, the sequence moves to step S407. In step S407, the check unit I / F 231 notifies the check device I / F 215 that the check result is "failed", that is, the instruction paper is to be discharged to the top tray 320 of the large-capacity stacker 107. The sequence then moves to steps S408 to S412, and the processing can then be completed in the same manner as when the check result is "passed" described above. Note that the selection of the discharge tray of the large-capacity stacker 107 is made by selecting the paper conveying path 321 or the sheet conveying path 322 as the conveying path. For example, an instruction for selecting a conveying path can be made from the accessory I / F 214 of the check unit 106 to the large-capacity stacker 107 via the cable 225 and the accessory I / F 220 of the large-capacity stacker 107.

[0065] Steps S408 to S411 are processes performed when a paper jam occurs in the printing device 101. In step S408, the checking unit I / F 231 determines whether a paper jam has occurred. Specifically, if the checking unit I / F 231 receives the paper jam occurrence information of the printing processing device from the checking device I / F 215, it can be determined that a paper jam has occurred. If it is determined that a paper jam has occurred, the paper jam processing described in the embodiment is performed in step S409. As an overview, the paper jam processing includes checking suspension processing, waiting for the completion of conveyance of the remaining paper in the device, and calculation of the checking recovery start page.

[0066] In step S410, the checking unit I / F 231 waits for receiving a paper jam elimination notification of the print processing apparatus from the checking device I / F 215. When the checking unit I / F 231 receives a paper jam elimination notification of the print processing apparatus from the checking device I / F 215 in step S410, the sequence moves to step S411.

[0067] In step S411, the CPU 226 restarts checking from the restoration start page calculated in step S409. In step S412, the checking process is repeated until checking is completed for all sheets.

[0068] Restart the inspection synchronously with the restart of printing. In other words, when printing is suspended due to a paper jam, printing is restarted from the next page after the last page that was correctly ejected. In this embodiment, the inspection after the restart of printing is also synchronized with the printing, and the inspection is restarted from the page where printing is restarted.

[0069] Note that the example described here is merely an example, and for example, instead, the image reading start instruction from the user made through the display unit 245 may be automatically made in conjunction with an instruction to start printing made in the printing apparatus 101, the information processing apparatus 109, or the client computer 110, etc., and its form is not limited. In addition, the image reading end instruction made by the user through the display unit 245 may be automatically made in conjunction with the end of printing in the printing apparatus 101, and its form is not limited.

[0070] Processing performed by the inspection unit

[0071] Figure 5 2 is a flowchart showing the operation performed during inspection by the inspection unit 106. Note that since the inspection is performed in synchronization with printing, some operations performed by the printing apparatus 101 will also be described.

[0072] In step S501, the CPU 201 of the printing apparatus 101 receives a print job and starts printing. Then, the sequence moves to step S502, and if there is paper to be checked, the sequence moves to step S503. Step S502 indicates that the steps from S502 to S514 are repeated and the conditions for the repetition. In step S502, the condition is that there is an unchecked sheet to be checked.

[0073] In step S503, the printing device 101 prints the image on paper. Next, in step S504, the imaging unit 218 of the inspection unit 106 scans the image printed on the conveyed paper using the CIS 315 and the CIS 316. Then, the sequence moves to step S505, in which the inspection device I / F 215 of the inspection unit 106 sends the image scanned in step S504 to the inspection unit I / F 231 of the inspection device 108.

[0074] Then, the sequence moves to step S506. In step S506, if the CPU 201 of the printing apparatus 101 detects a paper jam, the sequence moves to step S507. At this time, a paper jam may occur anywhere in the printing apparatus 101, the inspection unit 106, and the large-capacity stacker 107, and the position of the paper jam is not limited. If a paper jam occurs in the inspection unit 106 or the large-capacity stacker 107, etc., the CPU 201 obtains corresponding paper jam information and paper jam position, etc. via the accessory I / Fs 214, 220, and 208. On the other hand, if a paper jam does not occur in step S506, the sequence moves to step S511.

[0075] Once the sequence moves to step S507, the CPU 201 of the printing apparatus 101 performs the paper jam processing described in the embodiment. As an overview, the paper jam processing includes notification of paper jam occurrence information and waiting until all jammed paper in the apparatus is processed. Once all jammed paper in the apparatus is processed, the paper jam processing screen is displayed. Note that this embodiment assumes that, for example, the conveyance of sheets upstream of the jammed paper is stopped and these sheets remain in the apparatus.

[0076] In step S508, the CPU 201 waits until the jammed paper is removed and the paper jam state is cleared. Once the paper jam state is cleared, the sequence moves to step S509.

[0077] In step S509, the CPU 201 of the printing apparatus 101 notifies the CPU 216 of the checking unit 106 and the CPU 221 of the large-volume stacker 107 that the jam has been cleared via the accessory I / Fs 208, 214, and 220. In addition, the CPU 201 notifies the CPU 234 of the information processing apparatus 109 that the jam has been cleared via the NWI / Fs 207 and 238.

[0078] Next, in step S510, the CPU 201 outputs a print restart instruction. The destination of the instruction is the printing device 101, and the inspection unit 106 and the large-volume stacker 107 downstream of the printing device 101. In addition, the inspection device I / F 215 of the inspection unit 106 outputs an inspection restart instruction to the inspection unit I / F 231 of the inspection device 108. In response to the instruction, reprinting of the print job after the jammed paper is started, and the sequence moves to step S511.

[0079] In step S511, if the inspection device I / F 215 of the inspection unit 106 has received the inspection result "failure" from the inspection unit I / F 231 of the inspection device 108, the sequence moves to step S512. In step S512, the CPU 216 of the inspection unit 106 instructs the accessory I / Fs 208, 214, and 220 to discharge all the paper that has been supplied from the paper feed tables 103 and 104 and exists in the paper conveyance path after the paper for which the inspection result is "failure" to the top tray 320.

[0080] If the inspection device I / F 215 does not receive the inspection result of "failure" in step S511, the sequence moves to step S513, in which the CPU 216 instructs the accessory I / Fs 214 and 220 to discharge the paper to the discharge destination specified in the print job. Then, the sequence moves to step S514, and the processing of steps S502 to S514 is repeated until the inspection is completed for all sheets. Once the inspection is completed for all sheets, printing is also completed, and thus the flow is also completed. Note that the top tray 320 is a tray for discharging printed sheets whose inspection results are judged to be unfavorable and subsequent sheets, and therefore cannot be specified as a discharge destination, or is preferably not specified as a discharge destination.

[0081] Next, a specific embodiment for automatically calculating the inspection recovery start page and restarting the inspection when a paper jam occurs will be described.

[0082] First embodiment

[0083] This embodiment will describe the use of the inspection device 108 Figure 8 The inspection status management table 800 shown in FIG. 8 is used to automatically calculate the inspection recovery start page in the event of a paper jam.

[0084] Paper jam handling by detection device

[0085] Figure 6 FIG. 1 is a flowchart showing the operation performed by the inspection device 108 in the event of a paper jam. Specifically, FIG. Figure 4 Details of the operation performed in step S409 of the flowchart.

[0086] In step S601 , the CPU 226 of the inspection device 108 issues an inspection suspension instruction to the inspection device I / F 215 via the inspection unit I / F 231 , and controls the inspection unit 106 and the inspection device 108 to stop inspection.

[0087] Next, in step S602, the CPU 226 waits until all jammed sheets in the printing apparatus 101 are processed (eg, removed) and the remaining paper in the apparatus is ejected to the outside of the apparatus. When all jammed sheets in the apparatus are processed, the sequence moves to step S603.

[0088] In step S603, the CPU 226 of the inspection device 108 executes steps S610 to S615 to calculate the inspection recovery start page. Figure 8 The inspection status management table 800 referred to when executing steps S610 to S615 is described.

[0089] Check Status Management Table

[0090] Figure 8 The inspection status management table 800 referenced in order to calculate the inspection recovery start page is shown. The inspection status management table 800 is composed of a management table index 801, an inspection page number 802, an inspection status 803, and a correct paper discharge status 804. The management table index 801 is an index used when referring to the inspection table. The inspection page number 802 is a page number that identifies the inspection page. Here, as an example, the number is a unique number assigned sequentially from the start of the inspection. The inspection status 803 indicates whether the inspection page number has been checked. Here, "True" indicates that the inspection has been performed, and "False" indicates that the inspection has not been performed. The correct paper discharge status 804 indicates whether the inspection page is correctly discharged. Here, "True" indicates that the page has been correctly discharged to the specified discharge destination, and "False" indicates that the page has not been discharged. Note that the "page number" mentioned here has nothing to do with the page number of the original document, and can be regarded as a value indicating the sheet order, that is, sequential information. For example, even in double-sided printing in which multiple pages of the original document are arranged on one side, it can be Figure 8 The check page number in is regarded as sequence information indicating the printing order for each sheet forming a plurality of document pages on both sides.

[0091] Next, refer to Fig.9A and 9B The timing diagram in describes the timing for updating the information in the inspection status management table 800.

[0092] Update check status management table

[0093] Fig.9A and 9B The flow of the process of updating the information in the inspection status management table 800 based on the situation that a paper jam occurs on the third page but the papers up to the second page have been correctly discharged to the outside of the apparatus is shown. Fig.9A and 9B is a single continuous graph that is split between the two graphs and will therefore be treated as a single graph in the following description.

[0094] In step S901, the inspection unit 106 transmits the scanned image of the inspection target (first page) to the inspection device 108 ( Figure 5 The inspection device 108 compares the received scanned image with the reference image and determines the inspection result. Figure 4 The scanned image is received in step S403, the received image is compared with the reference image in step S404, and the inspection result is judged. The object of the judgment is misalignment or color shift with the reference position (described previously), etc.

[0095] In step S902, the inspection device 108 notifies the inspection unit 106 of the inspection result of the first page. It is assumed here that the inspection result of the first page is “acceptable.” At this timing, the inspection device 108 executes steps S406 and S407 according to the inspection result.

[0096] In step S903 , in the inspection status management table 800 , the inspection device 108 writes “true” into the inspection status 803 corresponding to the inspection page number 802 .

[0097] In step S904 , the printing apparatus 101 correctly discharges the checked first sheet to the outside of the apparatus, and notifies the checking unit 106 of discharge information indicating that the first sheet has been discharged.

[0098] In step S905 , the inspection unit 106 notifies the inspection device 108 of the received discharge information.

[0099] In step S906 , the checking device 108 writes “true” to the correct paper discharge status 804 corresponding to the checking page number 802 in the checking status management table 800 .

[0100] In steps S907 to S912, in the same manner as in steps S901 to S903, the check status 803 is written for the second and third pages into the check status management table 800. At the time point of step S912, the check status 803 is "true" until the third page.

[0101] In step S913 , the printing apparatus 101 detects a jam while the third page is being conveyed, and notifies the checking unit 106 of the position where the jam has occurred and that the jam has occurred on the third page.

[0102] In step S914, the checking unit 106 executes Figure 5 Steps S506 and S507 of the present invention are executed, and the received paper jam information ( Figure 7 Step S701).

[0103] In step S915, the inspection device 108 executes Figure 4 Steps S408 and S409 of the above procedure are executed, and the inspection process is suspended ( Figure 6 Step S601).

[0104] In steps S916 to S918, the checked second sheet is correctly discharged to the outside of the apparatus, and in the check status management table 800, "true" is written to the correct paper discharge status 804 corresponding to the check page number 802 in the same manner as in steps S904 to S906. At the time point of step S918, the correct paper discharge status 804 is "true" until the second sheet.

[0105] In step S919 , when the paper remaining in the apparatus has been completely discharged, the printing apparatus 101 notifies the checking unit 106 of the completion of the conveyance in the apparatus.

[0106] In step S920, the inspection unit 106 notifies the inspection device 108 of the received notification of the completion of the transport in the device ( Figure 7 Step S706).

[0107] In step S921, the inspection device 108 obtains the information in the inspection status management table 800, and then calculates the inspection recovery page (steps S610 to S615) in step S922. The information obtained in step S921 is Figure 8 The above describes the process for updating the information in the inspection status management table 800. Through the above, the inspection device 108 can refer to Figure 8 The completion and discharge of the inspection are recorded in units of the pages described. It is also possible to find the page for restarting the inspection based on it. The inspection status management table 800 can be created, for example, in units of jobs. For example, when a print job is completed, the table can be deleted, and when a new print job is started, a new table can be started. In this case, the index 801 and the inspection page number 802 match, so only one of them needs to be recorded.

[0108] Determination of the inspection recovery page by the inspection device

[0109] Next, return to Figure 6 , will refer to the flowchart and Figure 8 The inspection status management table 800 shown illustrates an example of a process for calculating an inspection recovery page.

[0110] In step S610 , the CPU 226 initializes the index for reference information in the inspection status management table 800 to 1.

[0111] In step S611, the CPU 226 refers to the inspection status 803 of which the index 801 in the inspection status management table 800 is 1. If the referenced inspection status 803 indicates "inspected" ("true"), the sequence moves to step S612. If the referenced inspection status 803 indicates "uninspected" ("false"), the sequence moves to step S614. Here, when the index 801 in the inspection status management table 800 is 1, the inspection status 803 is "inspected" ("true"), so the sequence moves to step S612.

[0112] In step S612, the CPU 226 refers to the correct paper discharge status 804 of which the index 801 in the check status management table 800 is 1. If the referenced correct paper discharge status 804 indicates "correct discharge" ("true"), the sequence moves to step S613. If the referenced correct paper discharge status 804 indicates "not yet discharged" ("false"), the sequence moves to step S615. Here, when the index 801 in the check status management table 800 is 1, the correct paper discharge status 804 is "correct discharge" ("true"), so the sequence moves to step S613.

[0113] In step S613, the CPU 226 increments the index for the reference information in the inspection status management table 800 by 1 after the sequence moves to step S611. Here, the index is set to 2. Thereafter, steps S611 to S613 are repeated for "inspected" and "correctly discharged". Figure 8 In the example shown, steps S611 to S613 are repeated until the index reaches 3.

[0114] In step S611, the CPU 226 refers to the check status 803 whose value of the index 801 in the check status management table 800 is 3. Since the referenced check status 803 is "checked" ("true"), the sequence moves to step S612.

[0115] In step S612, the CPU 226 refers to the correct paper discharge status 804 of index 801 3 in the check status management table 800. The referenced correct paper discharge status 804 indicates "not discharged yet" ("false"), so the sequence moves to step S615.

[0116] In step S615, the CPU 226 sets the inspection page number 802 of which the index 801 in the inspection status management table 800 is 3 as the inspection resumption start page. In other words, in step S615, the sheet number of the sheet that has been inspected and not correctly ejected is set as the first sheet number (page number) for the inspection to be resumed, i.e., the inspection resumption start page. Here, for example, 3 is set as the inspection resumption start page. This indicates that the processing will be resumed with the inspection of the third page.

[0117] Note that step S614 is processing performed in the case where a paper jam occurs upstream of the inspection unit 106. For example, in the case where a paper jam occurs upstream of the inspection unit 106, the paper downstream of the page where the paper jam occurred may have been correctly inspected and discharged. In this case, the inspection recovery start page is calculated in step S614 by setting the uninspected inspection page as the inspection recovery start page.

[0118] As described so far, in the present embodiment, for example, a series of sheets printed in one print job until the last sheet that has been checked and correctly discharged is regarded as having been printed. Then, the inspection resumption start page is determined so that the inspection is resumed from the next unchecked page or the page that has not been correctly discharged. In other words, the inspection resumption start page is determined so that the inspection is resumed from the first unchecked page or the page that has not been correctly discharged indicated in the inspection status management table 800. Next, the operation performed on the inspection unit 106 side will be described.

[0119] Check unit for paper jam handling

[0120] Figure 7 1 is a flowchart showing the operation performed by the printing device 101 and the checking unit 106 when a paper jam occurs. Figure 5 Details of the operation performed in step S507 of the flowchart in FIG.

[0121] In step S701, the CPU 201 of the printing apparatus 101 notifies the CPU 216 of the inspection unit 106 and the CPU 221 of the large-capacity stacker 107 of the paper jam state via the accessory I / Fs 208, 214, and 220, respectively. The CPU 216 also notifies the inspection unit I / F 231 of the inspection apparatus 108 of the paper jam state via the inspection apparatus I / F 215. The paper jam state includes paper jam position information that can be determined by detecting paper by sensors (not shown) provided in the printing apparatus 101, the inspection unit 106, and the large-capacity stacker 107. In addition, since the CPU 201 can detect that paper has been printed and discharged to the outside of the apparatus, it can detect which paper is jammed, and the information of the paper is also included in the paper jam state. Then, the CPU 201 notifies the CPU 234 of the information processing apparatus 109 of the paper jam state via the NW I / Fs 207 and 238. This enables the information processing apparatus 109 to know how many sheets of paper used in the print job are jammed.

[0122] In step S702, the CPU 201 stops the conveyance of the remaining paper upstream of the paper causing the paper jam (referred to as "jammed paper"). By stopping new conveyance of the remaining paper upstream of the jammed paper, all the paper upstream of the jammed paper that has started to be conveyed becomes the jammed paper, such as the paper that the user needs to manually remove.

[0123] In step S703, the CPU 201 sets the most downstream jammed paper in the sheet conveying path as the leading jammed paper in the internal parameters. Then, the most downstream jammed paper becomes the page for restarting printing in the jam recovery process (described later). This enables recovery for the jammed paper.

[0124] In step S704 , the CPU 201 discharges the remaining paper further downstream of the leading jammed paper, after which the sequence moves to step S705 .

[0125] In step S705, the CPU 201 waits until the remaining paper has been completely discharged. Once the remaining paper is completely discharged, the sequence moves to step S706. This is because in reference Figure 6 In the calculation of the inspection recovery start page described above, it is necessary to update the inspection status management table 800 in a state where the remaining paper in the apparatus has been ejected.

[0126] In step S706, the CPU 201 notifies the CPU 216 of the inspection unit 106 via the accessory I / Fs 208 and 214 that the remaining paper in the apparatus has been completely discharged. In addition, the CPU 216 notifies the inspection unit I / F 231 of the inspection device 108 via the inspection device I / F 215 that the remaining paper in the apparatus has been completely discharged.

[0127] In step S707, the CPU 201 displays the paper jam handling screen in the UI panel 203. The sequence then moves to Figure 5 Step S508.

[0128] According to the present embodiment, through the above sequence, the inspection unit 106 and the inspection device 108 can automatically restart the inspection after the paper jam processing. Therefore, when a paper jam occurs, the inspection can be restarted without burdening the operator with inputting the restart position.

[0129] More specifically, when a paper jam occurs, the printing device 101 stops conveying the sheet upstream of the jammed sheet, and discharges the sheet downstream of the jammed sheet. The checking device 108 also records whether each sheet has been checked and discharged. When resuming printing, the printing device 101 restarts printing from the leading sheet where the paper jam occurred. The checking unit 106 and the checking device 108 also identify sheets that have been checked but not correctly discharged or sheets that have not been checked after the discharged sheets, and restart the inspection from the identified sheets. This makes it possible to avoid redundant inspections and misalignment between the target sheet and the reference image, so that correct inspection can continue regardless of where the paper jam occurs in the conveying path.

[0130] The present embodiment and other embodiments described below are not limited to paper jams, and can also be applied to a case where, after printing is paused, printing is then restarted from a sheet that has already been printed and checked.

[0131] Second embodiment

[0132] The first embodiment describes that the checking device 108 performs calculations using the checking state management table 800. As another embodiment, it is conceivable that the checking device 108 automatically calculates the checking recovery start page when a paper jam occurs without using the checking state management table 800. Figure 8 The inspection status management table 800 shown in FIG. 8 is shown in FIG. 8 . A specific embodiment will be described below. The processing on the inspection unit 106 side is the same as that described in the first embodiment. Figure 7 , so they will not be described here.

[0133] Fig.10 1 is a flowchart showing the operation performed by the inspection device 108 when a paper jam occurs. Figure 4 Details of the operation performed in step S409 of the flowchart.

[0134] Steps S1001 and S1002 are the same as steps S601 and S602 and thus are not described here.

[0135] In step S1003 , the CPU 226 calculates a check recovery start page from the checked pages and the ejected pages in the internal parameters.

[0136] Here, we will refer to Fig.11 The timing chart in describes the flow of processing for calculating the check recovery start page from the number of checked pages and the number of ejected pages in the internal parameters without using the check status management table 800.

[0137] Fig.11 The flow of processing for updating the information of checked pages and ejected pages in the internal parameters based on the fact that a paper jam occurs on the third page but the papers up to the second page have been correctly ejected to the outside of the apparatus is shown.

[0138] In step S1101, the inspection unit 106 transmits the scanned image of the inspection object (first page) to the inspection device 108 ( Figure 5 The inspection device 108 compares the received scanned image with the reference image and determines the inspection result. Figure 4 In step S403, a scanned image is received, and in step S404, the received image is compared with a reference image, and an inspection result is determined.

[0139] In step S1102, the inspection device 108 notifies the inspection unit 106 of the inspection result of the first page. It is assumed here that the inspection result of the first page is “acceptable.” At this timing, the inspection device 108 executes steps S406 and S407 according to the inspection result.

[0140] In step S1103, the checking device 108 writes the checked page number for the checked page in the internal parameter, where "1" is written.

[0141] In step S1104 , the printing apparatus 101 correctly discharges the checked first sheet to the outside of the apparatus, and notifies the checking unit 106 of discharge information indicating that the first sheet has been discharged.

[0142] In step S1105 , the inspection unit 106 notifies the inspection device 108 of the received discharge information.

[0143] In step S1106, the inspection device 108 writes the ejected page number for the ejected page in the internal parameter. Here, "1" is written.

[0144] In steps S1107 to S1112, in the same manner as in steps S1101 to S1103, for the second and third sheets, the checked page numbers are written for the checked pages in the internal parameters. At the time point of step S1112, the checked page in the internal parameters is "3".

[0145] In step S1113 , the printing apparatus 101 detects a paper jam while the third page is being conveyed, and notifies the checking unit 106 of the position where the paper jam has occurred and that the paper jam has occurred on the third page.

[0146] In step S1114, the checking unit 106 executes Figure 5 Steps S506 and S507 are performed, and the received paper jam information ( Figure 7 Step S701).

[0147] In step S1115, the inspection device 108 executes Figure 4 Steps S408 and S409 of the above procedure are executed, and the inspection process is suspended ( Fig.10 Step S1001).

[0148] In steps S1116 to S1118, in the same manner as in steps S1104 to S1106, the checked second sheet is correctly discharged to the outside of the apparatus, and the discharge page number is written for the discharged page in the internal parameter. Assume that "2" is written at the time point of step S1118.

[0149] In step S1119 , when the remaining paper in the apparatus has been completely discharged, the printing apparatus 101 notifies the checking unit 106 of the completion of the conveyance in the apparatus.

[0150] In step S1120, the inspection unit 106 notifies the inspection device 108 of the received notification of the completion of the transport in the device ( Figure 7 , or step S706 in the above procedure.

[0151] In step S1121, the inspection device 108 obtains the discharged page in the internal parameter and calculates the inspection recovery page. Since the next discharged page is the inspection recovery start page, the discharged page in the internal parameter is increased and set to the inspection recovery start page. Then the sequence moves to Figure 4 Step S410.

[0152] By the above sequence, the inspection resumption start page can be calculated without using the inspection status management table 800. Therefore, when a paper jam occurs, inspection can be resumed without burdening the operator with input of a resumption position in the same manner as the first embodiment.

[0153] In the method for determining the inspection recovery start page according to the present embodiment, the order information of the last inspected sheet and the order information of the last sheet ejected correctly are recorded. Therefore, since the inspection status management table 800 is not used, less storage space is required than the first embodiment.

[0154] Third embodiment

[0155] The first and second embodiments describe the checking unit 108 as automatically calculating the checking recovery start page when a paper jam occurs. As another embodiment, it is conceivable that the checking unit 106 automatically calculates the checking recovery start page when a paper jam occurs.

[0156] This embodiment will describe the use of the inspection unit 106 Figure 8 The inspection status management table 800 shown in FIG. 8 is used to automatically calculate the inspection recovery start page when a paper jam occurs. In this embodiment, the inspection unit 106 calculates the inspection recovery start page and notifies the inspection device 108 of the calculation result.

[0157] Check unit for paper jam handling

[0158] Fig.13 1 is a flowchart showing the operation performed by the printing device 101 and the checking unit 106 when a paper jam occurs. Figure 5 Details of the operation performed in step S507 of the flowchart in FIG.

[0159] Steps S1301 to S1306 are the same processing as steps S701 to S706 and thus will not be described here.

[0160] In step S1307, the CPU 216 obtains the information in the inspection status management table 800 and calculates the inspection recovery page. This process is similar to that according to the first embodiment. Figure 6 Steps S610 to S615 are the same as those of FIG. 1 , and thus will not be described here.

[0161] In step S1308 , the CPU 216 notifies the checking unit I / F 231 of the checking restoration start page through the checking device I / F 215 .

[0162] In step S1309, the CPU 201 displays the paper jam handling screen in the UI panel 203. The sequence then moves to Figure 5 Step S508.

[0163] Check the update of the status management table and the calculation of the recovery page

[0164] The following will refer to Fig.14A and 14B The timing diagram in describes the timing for updating the information in the inspection status management table 800. Fig.14A and 14B is a single continuous graph split between the two graphs, and will therefore be treated as a single graph in the following description.

[0165] Fig.14A and 14B The flow of processing for updating the information in the inspection status management table 800 based on the situation that a paper jam occurs on the third sheet of paper but until the second sheet of paper has been correctly discharged to the outside of the apparatus is shown.

[0166] In step S1401, the inspection unit 106 transmits the scanned image of the inspection object (first page) to the inspection device 108 ( Figure 5 The inspection device 108 compares the received scanned image with the reference image and determines the inspection result. Figure 4 In step S403, a scanned image is received, and in step S404, the received image is compared with a reference image, and an inspection result is determined.

[0167] In step S1402, the inspection device 108 notifies the inspection unit 106 of the inspection result of the first page. It is assumed here that the inspection result of the first page is “acceptable.” At this timing, the inspection device 108 executes steps S406 and S407 according to the inspection result.

[0168] In step S1403 , in the inspection status management table 800 , the inspection unit 106 writes “true” into the inspection status 803 corresponding to the inspection page number 802 upon receiving the inspection result.

[0169] In step S1404 , the printing apparatus 101 correctly discharges the checked first sheet to the outside of the apparatus, and notifies the checking unit 106 of discharge information indicating that the first sheet has been discharged.

[0170] In step S1405 , the checking unit 106 writes “true” into the correct paper discharge status 804 corresponding to the checking page number 802 in the checking status management table 800 .

[0171] In steps S1406 to S1411, the check status 803 is written to the check status management table 800 for the second and third pages in the same manner as in steps S1401 to S1403. At the time point of step S1411, the check status 803 is "true" until the third page.

[0172] In step S1412 , the printing apparatus 101 detects a jam while the third page is being conveyed, and notifies the checking unit 106 of the position where the jam occurred and that the jam occurred on the third page.

[0173] In step S1413, the checking unit 106 executes Figure 5 Steps S506 and S507 of the present invention are executed, and the received paper jam information ( Fig.13 Step S1301).

[0174] In step S1414, the inspection device 108 executes Figure 4 Steps S408 and S409 of the above procedure are executed, and the inspection process is suspended ( Fig.12 Step S1201).

[0175] In steps S1415 to S1416, the checked second sheet is correctly discharged to the outside of the apparatus, and in the check status management table 800, "true" is written to the correct paper discharge status 804 corresponding to the check page number 802 in the same manner as in steps S1404 to S1405. At the time point of step S1416, the correct paper discharge status 804 is "true" until the second sheet.

[0176] In step S1417 , when the remaining paper in the apparatus has been completely discharged, the printing apparatus 101 notifies the checking unit 106 of the completion of the conveyance in the apparatus.

[0177] In step S1418, the inspection unit 106 obtains the information in the inspection status management table 800, and then calculates the inspection recovery page (steps S610 to S615) in step S1419. The information obtained in step S1418 is Figure 8 The information indicated in the inspection status management table 800 in the above is described as the flow of the process for updating the information in the inspection status management table 800.

[0178] In step S1420, the checking unit 106 notifies the checking device 108 of the checking recovery start page ( Fig.13, or step S1306 in the above procedure.

[0179] In step S1421, upon receiving the inspection recovery start page, the inspection device 108 sets the received inspection recovery start page in the internal parameters.

[0180] Paper jam handling by detection device

[0181] Fig.12 1 is a flowchart showing the operation performed by the inspection device 108 when a paper jam occurs. Figure 4 Details of the operation performed in step S409 of the flowchart.

[0182] Steps S1201 and S1202 are the same as steps S601 and S602 and thus will not be described again here.

[0183] In step S1203, the CPU 226 waits until a check resumption start page is received from the check unit I / F 231. Upon receiving the check resumption start page, the sequence moves to step S1204.

[0184] In step S1204, the CPU 226 stores the received check recovery start page in the internal parameter and moves the sequence to Figure 4 Step S410 in .

[0185] Through the above sequence, the checking unit 106 can calculate the checking resumption start page using the checking state management table 800. Therefore, when a paper jam occurs, the checking can be resumed without burdening the operator with input of a resumption position in the same manner as the first and second embodiments.

[0186] Fourth embodiment

[0187] The third embodiment describes that the checking unit 106 performs calculations using the checking status management table 800. As another embodiment, it is conceivable that the checking unit 106 automatically calculates the checking recovery start page when a paper jam occurs without using Figure 8 The inspection status management table 800 shown in FIG. 1 is a flowchart showing the operation performed by the inspection device 108 when a paper jam occurs in the present embodiment. Fig.12 The same, so a description thereof will not be given.

[0188] Fig.15 1 is a flowchart showing the operation performed by the printing device 101 and the checking unit 106 when a paper jam occurs. Figure 5 Details of the operation performed in step S507 of the flowchart in FIG.

[0189] Steps S1501 to S1506 are the same processing as steps S1301 to S1306, and thus will not be described here.

[0190] In step S1507, the CPU 216 of the checking unit 106 calculates the check recovery start page based on the checked pages and the ejected pages in the internal parameters. Fig.16A and 16B The timing chart in describes a processing flow of calculating the inspection recovery start page from the number of inspected pages and the number of ejected pages in the internal parameters without using the inspection status management table 800. Fig.16A and 16B is a single continuous graph split between the two graphs, and will therefore be treated as a single graph in the following description.

[0191] Fig.16A and 16B The flow of processing for updating the information of checked pages and ejected pages in the internal parameters based on the situation that a paper jam occurs on the third sheet of paper but the second sheet of paper has been correctly ejected to the outside of the apparatus is shown.

[0192] In step S1601, the inspection unit 106 transmits the scanned image of the inspection object (first page) to the inspection device 108 ( Figure 5 The inspection device 108 compares the received scanned image with the reference image and determines the inspection result. Figure 4 In step S403, a scanned image is received, and in step S404, the received image is compared with a reference image, and an inspection result is determined.

[0193] In step S1602, the inspection device 108 notifies the inspection unit 106 of the inspection result of the first page. It is assumed here that the inspection result of the first page is “acceptable.” At this timing, the inspection device 108 executes steps S406 and S407 according to the inspection result.

[0194] In step S1603, the checking unit 106 writes the checked page number for the checked page in the internal parameter. Here, "1" is written.

[0195] In step S1604 , the printing apparatus 101 correctly discharges the checked first sheet to the outside of the apparatus, and notifies the checking unit 106 of discharge information indicating that the first sheet has been discharged.

[0196] In step S1605, the checking unit 106 writes the ejected page number for the ejected page in the internal parameter. Here, "1" is written.

[0197] In steps S1606 to S1611, in the same manner as in steps S1601 to S1603, for the second and third sheets, the checked page numbers are written for the checked pages in the internal parameters. At the time point of step S1611, the checked page in the internal parameters is "3".

[0198] In step S1612 , the printing apparatus 101 detects a paper jam while the third page is being conveyed, and notifies the checking unit 106 of the position where the paper jam has occurred and that the paper jam has occurred on the third page.

[0199] In step S1613, the checking unit 106 executes Figure 5 Steps S506 and S507 of the present invention are executed, and the received paper jam information ( Fig.15 .

[0200] In step S1614, the inspection device 108 executes Figure 4 Steps S408 and S409 of the above procedure are executed, and the inspection process is suspended ( Fig.12 .

[0201] In steps S1615 to S1616, in the same manner as in steps S1604 and S1605, the checked second sheet is correctly discharged to the outside of the apparatus, and the discharge page number is written for the discharged page in the internal parameter. Assume that "2" is written at the time point of step S1616.

[0202] In step S1617 , when the remaining paper in the apparatus has been completely discharged, the printing apparatus 101 notifies the checking unit 106 of the completion of the conveyance in the apparatus.

[0203] In steps S1618 and S1619 , the checking unit 106 obtains the checked page and the ejected page in the internal parameters.

[0204] In step S1620, the checking unit 106 calculates the checking recovery page from the obtained discharged page. Since the next discharged page is the checking recovery start page, the discharged page in the internal parameter is increased by 1 and is set as the checking recovery start page.

[0205] In step S1621, the checking unit 106 notifies the checking device 108 of the check recovery start page ( Fig.15 , or step S1506 in the above procedure.

[0206] In step S1622, upon receiving the inspection recovery start page, the inspection device 108 sets the received inspection recovery start page in the internal parameters. The sequence then moves to Figure 5 Step S508.

[0207] By the above sequence, the inspection resumption start page can be calculated without using the inspection status management table 800. Therefore, when a paper jam occurs, inspection can be resumed without burdening the operator with input of a resumption position in the same manner as the third embodiment.

[0208] Other embodiments

[0209] The embodiments of the present invention may also be implemented by providing software (program) for performing the functions of the above-described embodiments to a system or device via a network or various storage media, and a computer or a central processing unit (CPU) or a microprocessing unit (MPU) of the system or device reads and executes the program.

[0210] While the present invention has been described with reference to embodiments, it is to be understood that the invention is not limited to the disclosed embodiments but is instead to be determined by the scope of the following claims.

Claims

1. A printing system, comprising: a printing unit configured to form an image on a sheet conveyed along a conveying path; a receiving section configured to receive an image obtained by reading a sheet on which an image is formed on the conveying path; an inspection section configured to inspect the read image by comparing the read image with a reference image, and to record first information specifying whether the sheet has been inspected and second information specifying whether the sheet has been correctly discharged; as well as A control unit is configured to determine, based on the first information and the second information, a sheet from which the inspection is restarted by the inspection unit after printing is restarted, when the inspection is restarted due to a jam occurring in a conveyance path of the sheet.

2. The printing system according to claim 1, in, The inspection section is configured to associate and record the sequence information of the sheets to be inspected, the first information, and the second information, and The control section is configured to determine, based on the sequence information, the first information, and the second information, a sheet from which the inspection is to be restarted.

3. The printing system according to claim 1, in, The inspection section includes an acquisition section including an image reading unit configured to read an image of a sheet and an inspection execution section configured to compare the read image with the reference image.

4. The printing system according to claim 3, in, The inspection execution section stores information indicating that inspection of the sheet has been completed as the first information, and stores information indicating that the sheet has been correctly discharged as the second information.

5. The printing system according to claim 1, in, The checking section is configured to record, as the second information, information indicating that the sheet has been correctly discharged in response to the notification of discharge performed by the printing section.

6. The printing system according to any one of claims 1 to 5, in, The inspection section is configured to inspect a position and a color of an image formed on a sheet.

7. An inspection method for inspecting an image formed on a sheet conveyed along a conveying path, the inspection method comprising: receiving an image obtained by reading a sheet on which an image is formed on the conveying path; checking the read image by comparing the read image with a reference image; recording first information specifying whether a sheet has been checked and second information specifying whether the sheet has been correctly discharged; as well as When the inspection is restarted due to a jam occurring in a conveyance path of a sheet, a sheet from which the inspection is restarted after printing is restarted is determined based on the first information and the second information.

8. A computer-readable medium storing a program which, when executed by a computer, causes the computer to execute an inspection method for inspecting an image formed on a sheet conveyed along a conveying path, the inspection method comprising: receiving an image obtained by reading a sheet on which an image is formed on the conveying path; checking the read image by comparing the read image with a reference image; recording first information specifying whether a sheet has been checked and second information specifying whether the sheet has been correctly discharged; as well as When the inspection is restarted due to a jam occurring in a conveyance path of a sheet, a sheet from which the inspection is restarted after printing is restarted is determined based on the first information and the second information.

Images