JP2006082398A - Printer - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a printer capable of inspecting print contents of paper printed with the other printer in the printer having a function for inspecting printing results. <P>SOLUTION: Printed paper 58 printed with the other printer 18 is set to a paper feeding tray 24 of the printer 16 having the inspection function. Original manuscript image data 56 corresponding to the print contents of the set printed paper 58 are acquired via a network. The printed paper 58 is sent from the paper feeding tray to a reading part 42 by transferring it with the same transfer path 34 as the normal printing. On that occasion, it is controlled so as not to heat a fixing roller 38. Inspection image data 60 are acquired by reading an image printed on the printed paper 58 with the reading part 42. It is determined with a determination part 48 whether the printing is good or not by collating the original manuscript image data 56 with the inspection image data 60. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an electrophotographic printing apparatus, and more particularly to a printing apparatus that inspects a printed image.

  2. Description of the Related Art There is known a printing apparatus that prints image data obtained by reading an image on a two-dimensional medium such as paper, or image data based on a page description language, bitmap data, or the like on an electrophotographic method. In such a printing apparatus, there is a demand for inspecting whether a printed image is the same as the original image. Patent Document 1 below reads a printed image, acquires image data to be inspected (hereinafter referred to as inspection image data), and compares it with original image data (hereinafter referred to as original image data). An inspection device for collation is disclosed.

  Patent Document 2 discloses an inspection apparatus that inspects a defective product by comparing an image of the surface of a photographed article with a reference image stored in advance.

  In the present specification and claims, the paper is a flat print object such as a postcard, a thick paper, and a transparent resin sheet such as an OHP sheet, in addition to a paper such as a high-quality paper used in a copying machine. Used as an all-inclusive term.

Japanese Patent No. 2866339 JP-A-3-267744

  The apparatus described in Patent Document 1 discloses that an image printed by the own apparatus is inspected. However, there is a desire to inspect not only images printed by the own device but also images printed by other devices. The present invention provides a printing apparatus suitable for inspecting not only an image printed by itself but also an image printed by another machine.

  A printing apparatus according to the present invention prints a print image on a sheet based on original image data, reads the print image by a reading unit, and compares the acquired inspection image data with the original image data to inspect the print image. A printing device to be inspected by the means, and a preprinted paper storage unit for storing paper printed by a device other than the printing device, and original image data corresponding to the print contents of the stored paper, Document image data storing means for storing, and conveying means for conveying the accommodated sheet from the already printed sheet accommodating means to the reading means, wherein the reading means reads an image of the already printed sheet to be conveyed The inspection unit acquires inspection image data, and the inspection unit performs inspection by comparing the inspection image data with the stored document image data.

  Further, the printing apparatus according to the present invention does not heat the sheet by the fixing roller when inspecting the already printed image. For this reason, it is possible to prevent the fixing roller from being heated when inspecting an already printed image. In addition, the fixing roller can be retracted from the sheet conveyance path, and an additional roller pair can be provided to convey the sheet at this time.

  It is also preferable to print an identification code for specifying the print content in order to associate the print content of the already-printed paper to be inspected with the original document image data.

  In addition, the printing apparatus of the present invention is connected to a network and acquires document image data corresponding to the already-printed paper to be inspected, and the document image information from the printing apparatus that printed the document image data via the network.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a diagram illustrating a schematic configuration of a printing system 10 according to the present embodiment. The printing system 10 includes a print server 12 for instructing printing and a plurality of printing devices 16 and 18 connected to the print server 12 via a network 14. As will be described later, the printing device 16 has a function of inspecting whether a printed image is as the original image. On the other hand, the printing device 18 is a device that does not have this inspection function. In the embodiment, one printing device 16 is provided in the network 14, but a plurality of printing devices 16 may be provided. One or a plurality of printing apparatuses 18 having no inspection function are provided in the network 14.

  The printing devices 16 and 18 perform printing in response to an instruction from the print server. In response to a print request from itself or another terminal (not shown) connected to the network, the print server 12 converts the print content data represented by PDL (page description language) or bitmap data into raster data. The image data is converted to image data and the like and sent to the printing devices 16 and 18. Upon receiving the image data to be printed, the printing apparatus 16 generates document image data 20.

  The printing device 18 without the inspection function is the same as the conventional device, and the description thereof is omitted. Hereinafter, the printing device 16 with the inspection function will be described. The printing unit 22 performs printing on a sheet sent from the sheet feeding tray 24 based on the document image data 20. In the printing unit 22, a belt-shaped image carrier 26 is wound around a roller, and an electrostatic image based on the document image data 20 is formed on the image carrier 26 by an electrostatic image forming unit 28. Is done. The formed electrostatic image is sent to the developing unit 30 as the image carrier 26 moves, and the developing unit 30 applies toner to the electrostatic image to form a toner image. The toner image is further sent to the transfer unit 32 by the movement of the image carrier 26. In the transfer unit 32, the image carrier 26 faces the paper conveyed through the conveyance path 34, and the toner image on the image carrier 26 is transferred onto the paper. The sheet on which the toner image has been transferred is sent to the fixing unit 36 along the conveyance path 34. The fixing unit 36 is provided with a fixing roller 38 and a counter roller 40 opposite to the fixing roller 38, and a pair of the fixing roller 38 and the counter roller 40 pinches the sheet to apply pressure. The fixing roller 38 is heated, and the toner on the paper is heated and melted by this heat, and is fused to the paper together with the pressure.

  The paper on which the document image data is printed is further sent along the conveyance path 34 and sent to the reading unit 42. The reading unit 42 is provided with a line sensor 44 that reads an image on a sheet, and image information read by the line sensor 44 is sent out. The image read by the line sensor 44 is combined with inspection image data 46 for one sheet. The inspection image data 46 is compared with the original image data 20 by the determination unit 48, and it is determined whether the inspection image data 46 has been printed normally based on the degree of coincidence.

  The determination unit 48 instructs the transport switching unit 50 that switches the paper transport path based on whether the printed image is normal or abnormal, and switches the paper transport destination to the normal tray 52 or the abnormal tray 54. The conveyance switching unit 50 is provided with a switching guide 55, and its position is changed based on the normality / abnormality determination, and the paper destination is switched. The normally printed paper is conveyed to the normal tray 52, and the abnormal paper is conveyed to the abnormal tray 54.

  In the above description, the case where the printing apparatus 16 inspects the result printed by the own apparatus has been dealt with. Furthermore, it is possible to inspect printed matter printed by another printing apparatus 18 by using the inspection function of this apparatus. For example, a print instruction is issued from the print server 12 to the printing apparatus 18 having no inspection function, and printing is performed here. After printing is completed, the already printed paper (printed paper 58) is set in the paper feed tray 24 of the printing apparatus 16 that matches the paper size. On the other hand, the original image data 56 used for printing the set preprinted paper is acquired from the print server 12. In the printing apparatus 16, the document image data 56 is not used for printing, but is used as reference data for inspection. In this respect, it is the same as the original image data 20 when printing by the own machine.

  The preprinted paper 58 is transported on the paper transport path 34 during normal printing, and is sent to the reading unit 42 through the printing unit 22. Here, the printed image is read, and inspection image data 60 is acquired. The inspection image data 60 and the document image data 56 are collated by the determination unit 48 to determine whether printing is good or bad.

  When the preprinted paper 58 is inspected, the preprinted paper passes through the printing unit 22. At this time, as in normal printing, when the sheet is heated by the fixing roller 38, the sheet may contract. When the shrinkage occurs, the printed image is also deformed, and the consistency with the original image data 56 is reduced, so that there is a possibility that many of the images that are determined to be abnormal although normal at the time of printing are determined. . Therefore, when only the inspection is performed, the heating by the fixing roller 38 may reduce the inspection accuracy, and it is preferable not to perform this. For this reason, in the printing apparatus 16 of the present embodiment, a heating control unit 62 that controls the heater that heats the fixing roller 38 is provided. The heating control unit 62 controls the heater to be turned on so that the fixing roller 38 is heated when printing is performed by the own machine, that is, the printing device 16, and when only the inspection is performed, the heater is turned off and the fixing roller 38 is turned off. Control not to heat.

  FIG. 2 is a diagram illustrating another example of the printing apparatus, and the same components as those of the printing system 10 illustrated in FIG. 1 are denoted by the same reference numerals. In the printing apparatus 70, the configuration of the fixing unit 72 is different from that described above. The fixing roller 74 can be retracted from a position indicated by a broken line to a position indicated by a solid line by a driving unit such as an actuator. In the retracted position, the sheet does not contact the sheet conveyed on the conveyance path 34 and the sheet is not heated. Not done. When the fixing roller 74 is in the retracted position, the sheet is not subjected to a conveyance driving force by the fixing roller 74 and the opposing roller 40, so an additional roller pair 76 is provided adjacent to the roller pair 74 and 40. . When the fixing roller 74 is in the retracted position, the sheet is conveyed by the additional roller pair 76. Other configurations and operations thereof are the same as those of the printing device 16, and a description thereof will be omitted.

  FIG. 3 is a diagram showing an example in which an identification code 80 for specifying the print contents for each page is printed on the preprinted paper 58. When inspecting the already-printed paper 58, if the paper 58 is supplied to the reading unit 42 in the printed order, the correspondence between the document image data 56 and the inspection image data 60 can be taken. Alternatively, when the data is sent in a state where more than one overlaps, the correspondence between the two data can no longer be taken, and inconsistency, that is, abnormality determination is performed in the inspection. In order to solve this problem, an identification code 80 for specifying the content of the page can be printed for each page when printing is performed by another machine. As shown in FIG. 3, the identification code “0001” is printed on the first page 58-1 of the preprinted paper, and the identification code “0002” is printed on the second page 58-2. It is printed in the same way. The determination unit 50 reads this identification code, reads the document image data 56 specified by this code, and collates it with the inspection image data 60. As a result, even if the reading order changes from that at the time of printing, the document image data 56 and the inspection image data 60 can be associated with each other.

  FIG. 4 is a diagram illustrating an example in which an identification code 82 for specifying a group is attached to the printed paper 58 for each group. When inspecting sheets printed by a plurality of print jobs one after another, it may be unclear which print job printed the bundle 84 of preprinted sheets 58 to be inspected. For each print job, an identification code 82 for specifying the job is printed on the first page. The identification code 82 may be printed on the first page of the print content, or may be printed by inserting a new page before the first page. Based on the identification code 82, the determination unit 48 identifies the print job of the bundle 84, reads the corresponding document image data 56, and performs collation.

  The above-described identification codes 80 and 82 may be read by the reading unit 42, or a code reading sensor may be provided corresponding to the paper feed tray 24. Further, the identification codes 80 and 82 are not limited to letters and numbers, but may be barcodes or the like.

  In the above embodiment, the document image data 56 has been described as being acquired via the network 14, but it can also be acquired via a recording medium. In this case, it is necessary to provide a reading device for the target recording medium in the printing devices 16 and 70 with the inspection function.

1 is a diagram illustrating a schematic configuration of a printing system according to an embodiment. It is a figure which shows schematic structure of another printing system, especially the system containing the other structural example of the printing apparatus with an inspection function. It is a figure which shows the example of the identification code for specifying the printing content for every page. It is a figure which shows the example of the identification code for specifying a certain collection, such as a print job.

Explanation of symbols

  10 printing system, 12 print server, 14 network, 16, 70 printing device (with inspection function), 18 printing device (without inspection function), 20, 56 original image data, 22 printing section, 24 paper feed tray, 34 transport path 36, 72 Fixing unit, 38, 74 Fixing roller, 42 Reading unit, 46, 60 Inspection image data, 58 Preprinted paper, 62 Heating control unit, 76 Additional roller pair.

Claims (7)

Printing an image on paper based on the original image data, inspecting the printed image by comparing the inspection image data acquired by reading the printed image with the reading unit and the original image data, and printing A device,
Pre-printed paper storage means for storing pre-printed paper printed by an apparatus other than the printing apparatus;
Document image data storage means for acquiring and storing document image data corresponding to the print contents of the stored already-printed paper;
A transport unit configured to transport the stored paper from the pre-printed paper storage unit to the reading unit;
Have
The reading unit reads an image of a printed sheet to be conveyed, acquires inspection image data,
The inspection means performs inspection by comparing the inspection image data with the stored document image data.
Printing device. The printing apparatus according to claim 1,
The printed paper storage means is a paper feed tray for storing unprinted paper in normal printing of the printing apparatus,
The transport unit is a transport mechanism that sends unprinted paper to the reading unit via a printing unit in normal printing of the printing apparatus.
Printing device. The printing apparatus according to claim 2,
The printing unit of the printing apparatus transfers an image formed with toner onto a sheet, and fixes the toner on the sheet by heating and pressurizing with a fixing roller. The heating by the fixing roller is not performed.
Printing device.   The printing apparatus according to claim 3, wherein the fixing roller is not heated when inspecting the already-printed paper.   The printing apparatus according to claim 3, wherein when inspecting the printed paper, the fixing roller is retracted from the conveyance path, and the printing apparatus is disposed in the vicinity of the fixing roller, A printing apparatus having an additional roller pair for conveying a sheet in place of a fixing roller during inspection.   6. The printing apparatus according to claim 1, wherein an identification code for specifying the content printed on the paper is printed on the printed paper, and the inspection unit includes: A printing apparatus that identifies document image data corresponding to the print contents of the paper based on the identification code.   The printing apparatus according to claim 1, wherein the printing apparatus is connected to another printing apparatus that has performed printing on the already-printed paper to be inspected via a network. A printing apparatus in which document image data corresponding to the already-printed paper is acquired via the network.

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