JP6225631B2 - Image forming apparatus and program - Google Patents

Description

  The present invention relates to an image forming apparatus and a program.

  In Patent Document 1, an image forming apparatus including at least a sheet feeding unit that feeds a sheet, an image forming unit that forms an image on the fed sheet, and a control unit, an image is formed by the image forming unit. An image reading unit that reads the image from the paper on which the image is formed, and the control unit compares the image read from the paper using the image reading unit with an image to be formed on the paper, Based on the difference, it is determined whether or not there is a printing failure, and when the printing failure is detected, the paper feeding unit is controlled to interrupt the paper feeding operation, and for a predetermined number of fed paper sheets Continuously forming an image, reading an image, and detecting a printing defect, and when the number or the ratio of the defective sheets out of the predetermined number of sheets is equal to or less than a predetermined reference value, the paper feeding Control to restart the paper feeding operation Performed, it discloses the image forming apparatus characterized by.

  On the other hand, Patent Document 2 is a printing apparatus that executes a printing process on a print medium, and includes an input unit that inputs first image data to be printed on the print medium, and the first input by the input unit. Print processing means for executing print processing on the print medium based on the first image data; and a print processing means for reading the print medium on which the first image data has been printed by the print processing means and determining print defects. The reading means for acquiring the second image data, and when a predetermined post-processing is performed on the print medium on which the first image data has been printed, used to determine the printing failure, A determination process for specifying a determination area in the second image data, the determination area representing an image area that can be visually recognized on the print medium even after the predetermined post-processing; Picture The presence of the printing defect is determined by comparing the data and the second image data applied to the determination area, and the predetermined post-processing is performed on the print medium on which the first image data is printed. If not, the determining unit determines whether or not there is a printing defect by comparing the first image data and the second image data without executing the specific process. A printing apparatus is disclosed.

  Japanese Patent Application Laid-Open No. 2003-228688 discloses a print monitoring device in a printer that develops data to be printed into data for each sheet and prints on the sheet, a memory unit that stores the data related to printing, and prints on the sheet A sensor unit that reads the read data, and means for comparing the data read by the sensor unit with the data stored in the memory unit to determine whether the printing result is good or bad. A print monitoring apparatus is disclosed.

JP 2010-042601 A Japanese Patent No. 4562188 Japanese Patent Laid-Open No. 10-166697

  SUMMARY OF THE INVENTION An object of the present invention is to provide an image forming apparatus and a program that can suppress the frequency with which an image formed on a recording medium is determined to be image formation failure.

In order to achieve the above object, an image forming apparatus according to claim 1 includes a forming unit that forms an image on a recording medium, and a reading unit that reads a formed image that is an image formed on the recording medium by the forming unit. And a plurality of types of determination items used for determining the quality of the formed image at each of the required image quality levels and the required image quality level for each predetermined level. A request is made for each of the required image quality at the corresponding stage and a storage means that stores in advance a determination criterion required for the corresponding determination item, and a determination target image that is a formed image that is the determination target of the quality. together with accepting the request quality stage being, when a plurality of the determination target image is formed on one of said recording medium, said request quality, for each each of the plurality of judgment object image Wherein a receiving unit configured to apply only the criterion stored in the storage means in response to the stage of the request quality received by said receiving means, and the image information and the determination target image showing the determination target image The quality of the determination target image is determined based on a difference from the image information obtained by reading by the reading unit as a formed image, and the required image quality is determined for each of the plurality of determination target images by the receiving unit. And a determination unit that determines the quality of the determination target image by using the strictest determination criterion among the determination criteria corresponding to the required image quality .

Further, the invention according to claim 2 is required for a forming unit that forms an image on a recording medium, a reading unit that reads a formed image that is an image formed on the recording medium by the forming unit, and the formed image. The required image quality for each predetermined stage, the corresponding image quality for each of the required image quality stages, and each of the plurality of types of determination items used for determining the quality of the formed image. The required image quality and the required image quality at a stage required for a determination target image that is a formed image that is a determination target of pass / fail, and a storage unit that stores in advance a determination criterion required for the corresponding determination item. If the determination target image is formed on the plurality of said recording medium with accepted, the request image quality, a reception means for receiving for each each of the plurality of recording media, depending on the receiving unit The determination criteria stored in the storage unit corresponding to the received requested image quality level, image information indicating the determination target image, and the determination target image are obtained by reading the formed unit as the formed image by the reading unit. The quality of the determination target image is determined based on the difference from the received image information, and when the requested image quality is received for each of the plurality of recording media by the receiving unit, the requested image quality is supported. Determination means for determining the quality of the determination target image using the strictest determination criterion among the determination criteria .

The invention described in claim 3 is the invention described in claim 1 or 2 , further comprising display means for displaying a determination result by the determination means.
Note that the display by the display means includes a visible display by the display device, a permanent visible display by the image forming device, and an audible display by the sound generation device.

Furthermore, the invention according to claim 4 is the invention according to any one of claims 1 to 3 , wherein the accepting unit further accepts the determination criterion stored in the storage unit.

On the other hand, in order to achieve the above object, the program according to claim 5 includes: a forming unit that forms an image on a recording medium; and a reading unit that reads a formed image that is an image formed on the recording medium by the forming unit. And a plurality of types of determination items used for determining the quality of the formed image at each of the required image quality levels and the required image quality level for each predetermined level. A program for controlling an image forming apparatus, each having a storage unit that stores in advance a determination criterion required for the determination item corresponding to the required image quality at a corresponding stage, , together with accepting the request quality of the steps required for the determination target image is formed image to determine the subject of the quality, the plurality of the determination target image before the one When formed on the recording medium, the request image quality, a reception means for receiving for each each of the plurality of judgment object image, stored in said storage means in response to the stage of the request quality received by said receiving means And whether the determination target image is acceptable or not is determined based on a difference between the determination criterion and image information indicating the determination target image and image information obtained by reading the determination target image as the formed image by the reading unit. In addition, when the required image quality is received for each of the plurality of determination target images by the receiving unit, the determination is performed using the strictest determination criterion among the determination criteria corresponding to the required image quality. This is intended to function as a determination unit that determines the quality of the target image .

According to the first and fifth aspects of the present invention, compared with the case where the present invention is not applied, it is possible to suppress the frequency with which an image formed on a recording medium is judged as an image formation defect. The effect of is obtained. Moreover, as a result of reducing the amount of processing required for determination, an effect that determination processing can be performed at higher speed is obtained.

According to the second aspect of the present invention, compared to the case where the determination target image in each recording medium is determined with a uniform required image quality without using the required image quality corresponding to each of the plurality of recording media,
There is an effect that it is possible to more effectively suppress the frequency at which it is determined that the image formation is defective.

Further, according to the third aspect of the invention, an effect that the determination result can be easily grasped is obtained.

Furthermore, according to the fourth aspect of the present invention, the determination criteria can be stored and updated by the operator, and as a result, the convenience for the operator can be improved.

1 is a side cross-sectional view illustrating an example of a configuration of an image forming apparatus according to an embodiment. It is a bottom view which shows the structure of the inkjet recording head which concerns on embodiment. 1 is a block diagram illustrating a configuration of a main part of an electric system of an image forming apparatus according to an embodiment. 1 is a schematic diagram for explaining the overall configuration of an image forming apparatus according to an embodiment and the flow of image forming processing. It is a figure for demonstrating the detection method of the nozzle defect and color nonuniformity defect which concern on embodiment. It is a figure for demonstrating the detection method of the stain | pollution | contamination defect which concerns on embodiment. It is a figure which shows an example of the determination reference | standard table which shows the relationship between the printing image quality and loss paper determination reference | standard which concerns on embodiment. It is a flowchart which shows the flow of a process of the broken paper determination processing program which concerns on 1st Embodiment. It is a schematic diagram which shows an example of the screen of the selection menu of the printing image quality which concerns on 1st Embodiment. It is a schematic diagram which shows an example of the screen which designates a determination level according to the content of the printing defect which concerns on 3rd Embodiment. It is a figure for demonstrating the paper loss determination method of the imposition image which concerns on 4th Embodiment. It is a flowchart which shows the flow of a process of the waste paper determination processing program which concerns on 4th Embodiment.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

[First Embodiment]
FIG. 1 is a side sectional view showing a configuration of an image forming apparatus 10 according to the present embodiment. As shown in the figure, the image forming apparatus 10 is provided with a paper feeding / conveying section 12 that feeds and conveys recording paper P as a recording medium. On the downstream side in the conveyance direction of the recording paper P of the paper feeding / conveying section 12, a color material (pigment in this embodiment) reacts with the ink on the recording surface (front surface) of the recording paper P along the conveyance direction. A processing liquid application unit 14 that applies a processing liquid for aggregating and promoting separation of the colorant and the solvent, an image forming unit 16 that forms an image on the recording surface of the recording paper P, and an image formed on the recording surface A drying unit 18 for drying, an image fixing unit 20 for fixing the dried image on the recording paper P, and a discharge conveyance unit 24 for conveying the recording paper P on which the image is fixed to the discharge unit 22 are sequentially provided.

  The paper feeding / conveying unit 12 includes a storage unit 26 that stores the recording paper P. In addition, a motor 30 is provided in the accommodating portion 26. Further, the storage unit 26 is provided with a paper feeding device (not shown), and the recording paper P is sent from the storage unit 26 to the treatment liquid coating unit 14 by the paper feeding device.

The treatment liquid application unit 14 includes an intermediate conveyance drum 28 </ b> A and a treatment liquid application drum 36.
The intermediate conveyance drum 28A is rotatably disposed in a region sandwiched between the storage unit 26 and the treatment liquid coating drum 36, and a belt 32 is stretched between the rotation shaft of the intermediate conveyance drum 28A and the rotation shaft of the motor 30. Has been. Therefore, when the rotational driving force of the motor 30 is transmitted to the intermediate transport drum 28A via the belt 32, the intermediate transport drum 28A rotates in the direction of arrow A.

  The intermediate conveyance drum 28A is provided with a holding member 34 that holds the recording paper P with the leading end of the recording paper P interposed therebetween. Accordingly, the recording paper P sent out from the storage unit 26 to the treatment liquid application unit 14 is held on the outer peripheral surface of the intermediate conveyance drum 28A via the holding member 34, and is transferred to the treatment liquid application drum 36 by the rotation of the intermediate conveyance drum 28A. Be transported.

  Note that the intermediate conveyance drums 28B to 28E, the processing liquid coating drum 36, the image forming drum 44, the ink drying drum 56, the image fixing drum 62, and the discharge conveyance drum 68, which will be described later, also have a holding member 34 as in the intermediate conveyance drum 28A. Is provided. The holding member 34 transfers the recording paper P from the upstream drum to the downstream drum.

  The rotating shaft of the treatment liquid coating drum 36 is connected to the rotating shaft of the intermediate transport drum 28A by a gear (not shown), and rotates by receiving the rotational force of the intermediate transport drum 28A.

  The recording paper P transported by the intermediate transport drum 28 </ b> A is transferred to the processing liquid coating drum 36 via the holding member 34 of the processing liquid coating drum 36 and transported while being held on the outer peripheral surface of the processing liquid coating drum 36. Is done.

  A processing liquid application roller 38 is disposed in contact with the outer peripheral surface of the processing liquid application drum 36 above the processing liquid application drum 36, and the outer peripheral surface of the processing liquid application drum 36 is processed by the processing liquid application roller 38. A processing liquid is applied to the recording surface of the upper recording paper P.

  The recording paper P coated with the processing liquid by the processing liquid coating unit 14 is conveyed to the image forming unit 16 by the rotation of the processing liquid coating drum 36.

  The image forming unit 16 includes an intermediate conveyance drum 28 </ b> B and an image forming drum 44. The rotation shaft of the intermediate transport drum 28B is connected to the rotation shaft of the processing liquid coating drum 36 via a gear (not shown), and rotates by receiving the rotational force of the processing liquid coating drum 36.

  The recording paper P conveyed by the treatment liquid application drum 36 is transferred to the intermediate conveyance drum 28B via the holding member 34 of the intermediate conveyance drum 28B of the image forming unit 16, and is held on the outer peripheral surface of the intermediate conveyance drum 28B. It is conveyed in the state.

  The rotation shaft of the image forming drum 44 is connected to the rotation shaft of the intermediate conveyance drum 28B via a gear (not shown), and rotates by receiving the rotational force of the intermediate conveyance drum 28B.

  The recording paper P transported by the intermediate transport drum 28 </ b> B is transferred to the image forming drum 44 via the holding member 34 of the image forming drum 44 and transported while being held on the outer peripheral surface of the image forming drum 44.

Above the image forming drum 44, a head unit 46 is disposed adjacent to the outer peripheral surface of the image forming drum 44. The head unit 46 includes four inkjet recording heads 48 corresponding to four colors of yellow (Y), magenta (M), cyan (C), and black (K). These inkjet recording heads 48 are arranged along the circumferential direction of the image forming drum 44, and a clock signal of a CPU 100 described later so as to overlap the processing liquid layer formed on the recording surface of the recording paper P by the processing liquid application unit 14. In this manner, an image is formed by ejecting ink droplets from a nozzle 48a described later.
Note that the processing liquid may be ejected from the nozzles of the ink jet recording head 48 according to the present embodiment, but in the present embodiment, a case where ink droplets are ejected will be described as an example.

FIG. 2 shows the arrangement of the nozzles 48a in each inkjet recording head 48 in the present embodiment.
In the present embodiment, the number and arrangement of the nozzles 48a of each ink jet recording head 48 are not particularly limited, but as an example, N nozzles 48a-1, ..., 48a-N are arranged in one row. The inkjet recording head 48 is configured to be a long head in accordance with the width of the recording paper P. Therefore, the ink jet recording head 48 according to the present embodiment is a paper width printing type (so-called Full Width Array (FWA)) head that performs printing in one pass on the recording paper P that is continuously conveyed. Of course, the present invention is also applied to an image forming apparatus that performs image printing by so-called multi-pass that passes through the inkjet recording head 48 a plurality of times within the paper width.

  Here, the arrangement of the nozzles 48a in the inkjet recording head 48 is not limited to the above, and the nozzles 48a may be arranged in a plurality of rows, and the nozzles 48a in a plurality of rows may be alternately arranged two-dimensionally in a staggered manner. Also good. In addition, the inkjet recording head 48 is not limited to a single unit, and may be divided into a plurality of sections, or the plurality of inkjet recording heads 48 may be arranged in a staggered manner.

  The recording paper P on which the image is formed on the recording surface by the image forming unit 16 is conveyed to the drying unit 18 by the rotation of the image forming drum 44.

  The drying unit 18 includes an intermediate conveyance drum 28 </ b> C and an ink drying drum 56. The rotation shaft of the intermediate conveyance drum 28 </ b> C is connected to the rotation shaft of the image forming drum 44 through a gear (not shown), and rotates by receiving the rotational force of the image forming drum 44.

  The recording paper P conveyed by the image forming drum 44 is transferred to the intermediate conveyance drum 28C via the holding member 34 of the intermediate conveyance drum 28C, and conveyed while being held on the outer peripheral surface of the intermediate conveyance drum 28C.

  The rotation shaft of the ink drying drum 56 is connected to the rotation shaft of the intermediate conveyance drum 28C via a gear (not shown), and rotates by receiving the rotational force of the intermediate conveyance drum 28C.

  The recording paper P conveyed by the intermediate conveyance drum 28 </ b> C is transferred to the ink drying drum 56 via the holding member 34 of the ink drying drum 56 and conveyed while being held on the outer peripheral surface of the ink drying drum 56.

  Above the ink drying drum 56, a warm air heater 58 is disposed in the vicinity of the outer peripheral surface of the ink drying drum 56. Excess solvent in the image formed on the recording paper P is removed by the warm air from the warm air heater 58. The recording paper P on which the image on the recording surface has been dried by the drying unit 18 is conveyed to the image fixing unit 20 by the rotation of the ink drying drum 56.

  The image fixing unit 20 includes an intermediate conveyance drum 28D and an image fixing drum 62. The rotation shaft of the intermediate transport drum 28D is connected to the rotation shaft of the ink drying drum 56 via a gear (not shown), and rotates by receiving the rotational force of the ink drying drum 56.

  The recording paper P conveyed by the ink drying drum 56 is transferred to the intermediate conveyance drum 28D via the holding member 34 of the intermediate conveyance drum 28D, and conveyed while being held on the outer peripheral surface of the intermediate conveyance drum 28D.

  The rotation shaft of the image fixing drum 62 is connected to the rotation shaft of the intermediate conveyance drum 28D via a gear (not shown), and rotates by receiving the rotational force of the intermediate conveyance drum 28D.

  The recording paper P transported by the intermediate transport drum 28 </ b> D is delivered to the image fixing drum 62 via the holding member 34 of the image fixing drum 62 and transported while being held on the outer peripheral surface of the image fixing drum 62.

Above the image fixing drum 62, a fixing roller 64 having a heater inside is disposed in a state where the outer peripheral surface of the image fixing drum 62 can be pressed or separated. The recording paper P held on the outer peripheral surface of the image fixing drum 62 is sandwiched between the outer peripheral surface of the image fixing drum 62 and the outer peripheral surface of the fixing roller 64, and is in the state of being pressed against the outer peripheral surface of the fixing roller 64. As a result, the color material of the image formed on the recording surface of the recording paper P is fused to the recording paper P, and the image is fixed on the recording paper P. The recording paper P on which the image is fixed by the image fixing unit 20 is
The image fixing drum 62 is conveyed to the discharge conveyance unit 24 by the rotation.

  The discharge transport unit 24 includes an intermediate transport drum 28E and a discharge transport drum 68. The rotation shaft of the intermediate conveyance drum 28E is connected to the rotation shaft of the image fixing drum 62 through a gear (not shown), and rotates by receiving the rotational force of the image fixing drum 62.

  The recording paper P conveyed by the image fixing drum 62 is transferred to the intermediate conveyance drum 28E via the holding member 34 of the intermediate conveyance drum 28E, and conveyed while being held on the outer peripheral surface of the intermediate conveyance drum 28E.

  The rotation shaft of the discharge conveyance drum 68 is connected to the rotation shaft of the intermediate conveyance drum 28E via a gear (not shown), and rotates by receiving the rotational force of the intermediate conveyance drum 28E.

  The recording paper P conveyed by the intermediate conveyance drum 28E is delivered to the discharge conveyance drum 68 via the holding member 34 of the discharge conveyance drum 68, and is held on the outer peripheral surface of the discharge conveyance drum 68 to the discharge unit 22. Be transported.

In addition, the image forming apparatus 10 according to the present embodiment has an inline sensor as a reading unit for reading an image of a printed document or a printed image of a print defect detection pattern to be described later above the image fixing drum 62. 80.
The in-line sensor 80 according to the present embodiment reads an image printed on the recording paper P while the recording paper P is being conveyed to the discharge conveyance unit 24 while being held on the outer peripheral surface of the image fixing drum 62. Is arranged.

  The inline sensor 80 according to the present embodiment includes a light emitting unit and a light receiving unit (not shown), and light emitted from the light emitting unit is reflected by the recording paper P, and the reflected light is detected by the light receiving unit. Thus, the reflection optical density (so-called OD (Optical Density) value) of the printing area of the recording paper P is measured. The in-line sensor 80 is not limited to a reflective in-line sensor, and a transmissive in-line sensor may be used.

  Next, with reference to FIG. 3, the main configuration of the electrical system of the image forming apparatus 10 according to the present embodiment will be described.

  As shown in FIG. 1, an image forming apparatus 10 includes a CPU (Central Processing Unit) 100, a ROM (Read Only Memory) 102, a RAM (Random Access Memory) 104, an NVM (Non Volatile Memory) 106, a UI (user / user memory). An interface panel 108 and a communication interface 112 are included.

  The CPU 100 governs the overall operation of the image forming apparatus 10. The ROM 102 is a storage medium in which a control program for controlling the operation of the image forming apparatus 10, a loss paper determination processing program to be described later, various parameters, and the like are stored in advance. The RAM 104 is a storage medium used as a work area when executing various programs. The NVM 106 is a non-volatile storage medium that stores various types of information that must be retained even when the power switch of the apparatus is turned off.

The UI panel 108 includes a touch panel display or the like in which a transmissive touch panel is superimposed on a display, and various types of information are displayed on the display surface of the display. Also,
When the user touches the touch panel, desired information or an instruction, for example, an instruction for starting a waste paper determination processing program to be described later is input.

  The communication interface 112 is connected to a terminal device 114 such as a personal computer, receives various information (for example, image information indicating an image to be formed on the recording paper P) from the terminal device 114, and also receives various information (for example, image formation). Information for indicating the operating state of the device 10) to the terminal device 114.

  The CPU 100, the ROM 102, the RAM 104, the NVM 106, the UI panel 108, and the communication interface 112 are connected to each other via a bus BUS such as a system bus. Therefore, the CPU 100 accesses the ROM 102, the RAM 104, and the NVM 106, displays various information on the UI panel 108, grasps the contents of user operation instructions on the UI panel 108, and communicates via the communication interface 112 from the terminal device 114. The reception of various information and the transmission of various information to the terminal device 114 via the communication interface 112 are performed.

  Further, the image forming apparatus 10 includes a recording head controller 116 and a motor controller 118.

  The recording head controller 116 controls the operation of the ink jet recording head 48 in accordance with instructions from the CPU 100. The motor controller 118 controls the operation of the motor 30.

  The recording head controller 116 and the motor controller 118 are also connected to the bus BUS. Therefore, the CPU 100 controls the operation of the recording head controller 116 and the motor controller 118.

In the image forming apparatus 10 according to the present embodiment, a scanner unit 120 that reads a document or the like and generates image information, a storage unit 110 that stores later-described loss paper determination criterion information, and the like are identified. It has a stamp part 126 for imprinting a mark for this purpose. Scanner unit 120,
The storage unit 110 and the stamp unit 126 are also connected to the bus BUS and are controlled by the CPU 100.
Note that the inline sensor 80 described above is also connected to the bus BUS, and the CPU 100 can also access the inline sensor 80.

  Next, the overall configuration of the image forming apparatus 10 according to the present embodiment and the flow of image formation (hereinafter sometimes referred to as “printing”) processing will be described with reference to FIG.

  First, when an operator operates the scanner unit 120 to read an original of one unit of printing processing (job), image information of an original image (original image) is generated, and the image information of the original image is the CPU 100. Sent to. In addition, the operator operates the UI panel 108 and the like to specify the number of copies to be printed and instruct to print the original image.

The CPU 100 has a built-in program having functions as the image processing unit 100A and the waste paper determination unit 100B.
CPU 100 converts image information of a document image for which printing has been instructed into image information of a print image (image to be printed by image forming unit 16) in image processing unit 100A, and converts the image information of the print image to an image. Send to forming unit 16.

Paper (recording paper P) is supplied from the paper feeding / conveying unit 12, and the supplied paper reaches the discharging unit 22 via a paper conveying path (conveying path from the processing liquid coating unit 14 to the discharging / conveying unit 24 in FIG. 1). Be transported.
In the image forming unit 16 in the middle of the paper conveyance path, a print image is printed on a paper to obtain a printed matter. The printed matter is conveyed to the discharge unit 22 at the end of the sheet conveyance path and discharged.

  Next, functions of the inline sensor 80 according to the present embodiment will be described. The in-line sensor 80 according to the present embodiment is mainly an image reading apparatus for monitoring the printing state of a printed material in a printing process for a document or the like, or an image reading for reading a print defect detection pattern in a damaged paper determination process described later. It has a function as a device.

  Here, “scrap paper” refers to a printed matter that has been printed on the recording paper P for some reason and causes printing failure and cannot be used. “Scrap paper determination processing” is printed on the recording paper P. A process for determining whether a printed image has a printing defect. In the following, “good paper” may be used as a term corresponding to “waste paper”, and “good paper” refers to the recording paper P on which normal printing has been performed.

The inline sensor 80 reads the printed material being conveyed, generates image information of a printed material image (image of the printed material) (hereinafter, image information of the image read by the inline sensor 80 may be referred to as “read image information”), It is sent to the waste paper determination unit 100B.
The damaged paper determination unit 100B compares the image information of the print image and the image information of the printed material image, and determines whether the paper is defective or good based on the loss paper determination criterion.

Printing is continued as it is when it is determined to be good paper by the damaged paper determination unit 100B, but when it is determined to be damaged paper, the stamp 126 is stamped on the printed matter determined to be damaged paper. The UI panel 108 is notified of the occurrence of damaged paper, and the image forming apparatus 10 interrupts printing.
In the image forming apparatus 10 according to the present exemplary embodiment, when the operator operates the UI panel 108 to instruct printing, the waste paper determination criterion is specified. Details will be described later.

Here, in the above description, the case where the loss paper determination is performed based on the image information of the document image has been described as an example. However, in the loss paper determination according to the present embodiment, based on the image information of the print defect detection pattern described later. In some cases, the waste paper is determined.
In this case, the image information of the print defect detection pattern is stored in a storage unit such as the storage unit 110. In the case of performing the waste paper determination based on the print defect detection pattern, the image information of the print defect detection pattern is read from the storage unit such as the storage unit 110, and sent to the image forming unit 16 to be printed and printed. The image information of the printed material image obtained by reading the printed material by the in-line sensor 80 is sent to the damaged paper determination unit 100B, and the image information of the defective printing detection pattern is compared with the image information of the printed material image to determine the damaged paper. Is called.

  By the way, the image to be printed on the recording paper P includes an image that requires a high definition that causes a problem (such as a problem that it cannot be read by a barcode reader) even with a slight printing defect such as a barcode. Some images, such as structured documents, allow for some omission of images and some stains on the surface of printed matter. Hereinafter, the high quality of the image is referred to as “image quality”. For example, in the above example, the barcode image has high image quality, and the character image has low image quality.

  In the above-described loss paper determination, since the determination was made regardless of the image quality, when the operator visually determines the determined printed matter, it is considered that there is a slight print defect that does not have to be determined as waste paper. In some cases, what was supposed to be determined to be waste paper. On the other hand, in some cases, a printed matter that should be determined as waste paper may be determined as good paper according to the visual judgment of the operator.

If it is determined that the printed material that does not need to be treated as waste paper is waste paper, printing is interrupted or excessive maintenance (maintenance such as cleaning of the inkjet recording head 48) is performed to eliminate the occurrence of waste paper. Is required, and the operating rate of the image forming apparatus 10 is reduced.
In addition, when it is determined that the printed material to be broken paper is good paper, the broken paper is mixed in the printed material of other good paper, and the quality as the printed material is deteriorated. Furthermore, an operator's trouble for removing the slipped-in waste paper is also generated.

  On the other hand, when a large amount of printing processing is performed, a nozzle failure or the like may occur in the middle of printing, resulting in lost paper. In this case, in order to complete printing without causing a print failure according to the print image and without stopping halfway, it is necessary to determine the waste paper according to the image quality of the print image.

  Therefore, in the present embodiment, when the operator instructs the image forming apparatus 10 to execute printing, the paper loss criterion (scrap paper) selected from the stepwise level according to the print image of the printed matter. The criterion for determining whether or not is) is designated. Since the image forming apparatus 10 performs printing while performing loss paper determination based on the specified loss paper determination criterion, the loss determination is performed according to the required image quality according to the use of the image. Therefore, with respect to the image formed on the recording medium, the frequency at which it is determined that the image formation is defective (the frequency at which it is determined as damaged paper) is suppressed.

Next, the contents of printing failure (printing failure content) that is a cause of the occurrence of damaged paper in the image forming apparatus 10 according to the present embodiment and a method for detecting the occurrence of damaged paper will be described. In the image forming apparatus 10 according to the present embodiment, mainly, the nozzle 48a is defective (hereinafter sometimes referred to as “nozzle failure”), and the color unevenness in the printed image (hereinafter referred to as “color unevenness failure”). Is)
Damaged paper occurs due to dirt (hereinafter sometimes referred to as “dirt failure”) attached to the surface of the recording paper P.

  Nozzle defects include non-discharge failure where ink droplets (droplets) cannot be discharged due to clogging of the nozzle 48a, fine line failure where the amount of ink droplet discharge is reduced and the printed line becomes thin, near the discharge port of the nozzle 48a There is a landing position deviation defect in which the position of the ink droplet ejected by the foreign matter or the like formed on the surface is shifted (refer to FIG. 5C described later for details). Printing failure occurs due to these nozzle failures, and depending on the degree of the printing failure, the paper loss determination unit 100B determines that the paper is damaged.

Color unevenness occurs when color unevenness occurs in an image printed on the recording paper P due to variations in the size of ink droplets ejected from nozzles.
For example, the contamination defect causes a paper jam in the conveyance path of the recording paper P of the image forming apparatus 10, and ink droplets adhere to a drum such as the ink drying drum 56 or a roller such as the fixing roller 64, and the ink droplets are recorded. Occurs when attached to the paper P.

  In the image forming apparatus 10 according to the present embodiment, as described above, printing is performed while performing loss paper determination based on the loss paper determination criteria specified by the operator. The degree of printing failure is detected and monitored every time.

  With reference to FIG. 5, a method for detecting a nozzle defect and a color unevenness defect will be described. Detection of a nozzle defect and a color unevenness defect according to the present embodiment is performed using a print defect detection pattern for detecting each print defect.

FIG. 5A shows a print defect detection pattern 300 printed together with the image PG to be printed on the print surface of the recording paper P. The print defect detection pattern 300 includes the nozzle defect detection pattern 302 and the print defect detection pattern 302. The color unevenness detection pattern 304 is configured.
The print defect detection pattern 300 is normally printed outside the print area of the recording paper P, and after printing, the print defect detection pattern 300 is cut and discarded.

  FIG. 5B shows an example of the nozzle defect detection pattern 302. The nozzle defect detection pattern 302 shown in FIG. 5B is a so-called ladder pattern, and is a pattern printed on the recording paper P by the nozzle 48a as follows.

  That is, the nozzles 48a-1 to 48a-N of the ink jet recording head 48 shown in FIG. 2 are selected every predetermined number (three in the present embodiment) and simultaneously extend in the transport direction of the recording paper P. A straight line is printed (portion of position number 1 in FIG. 2). Next, the nozzle 48a is shifted by one and selected every predetermined number, and at the same time, a straight line extending in the conveyance direction of the recording paper P is printed (portion number 2 in FIG. 2). The nozzle 48a is again shifted by one and selected every predetermined number, and at the same time, a straight line extending in the conveyance direction of the recording paper P is printed (portion number 3 in FIG. 2). The pattern obtained as described above is a ladder pattern.

  [1] to [4] in FIG. 5C are partial enlarged views of the printing results of the nozzle failure detection pattern 302 corresponding to the mode of each nozzle failure.

  FIG. 5C [1] shows a case where the ejection of the nozzle 48a is normal. When some abnormality occurs in the nozzle 48a and normal printing cannot be performed, each line segment printed according to the abnormal state of the nozzle causes a deviation from the normal printing pattern.

FIG. 5 (c) [2] is an example of a case where ink droplets cannot be ejected from the nozzle 48a for some reason (undischarge failure), and the line at the position corresponding to the nozzle 48a where the failure has occurred. Minute print is missing.
FIG. 5 (c) [3] is an example of a case where the ejection amount of the ink droplets from the nozzle 48a is decreased for some reason (thin line defect), and printing is performed at a position corresponding to the nozzle 48a where the defect has occurred. The line segment is thin.
FIGS. 5C and 4 are examples of cases where the ink droplets ejected from the nozzles 48a are bent due to some cause (defect in landing position misalignment), and the positions corresponding to the nozzles 48a in which the defects have occurred. The line segment is inclined at.

  Note that a portion indicated by N in the nozzle failure detection pattern 302 in FIG. 5B shows a case where a discharge failure has occurred as an example of the failure detection.

  In the image forming apparatus 10 according to the present embodiment, the print defect detection pattern 300 printed on the recording paper P together with the image PG to be printed is read by the inline sensor 80 and sent to the damaged paper determination unit 100B as image information. The waste paper determination unit 100B compares the image information of the nozzle failure detection pattern 302 stored in advance in the storage unit 110 and the like with the image information (read image information) of the nozzle failure detection pattern 302 sent from the inline sensor 80. By doing this, the presence or absence of a nozzle failure and the degree of nozzle failure (failure level) are determined. The degree of nozzle failure may be, for example, the number of defective nozzles.

On the other hand, FIG. 5D shows an example of the color unevenness defect detection pattern 304.
FIG. 5D (1) shows an example of the color unevenness detection pattern 304 when the color unevenness defect does not occur and printing is performed normally. A color unevenness defect detection pattern 304 shown in the figure is a so-called solid pattern in which ink droplets having a uniform density are ejected from the nozzle 48a.

  FIG. 5D and [2] are print examples of the color unevenness defect detection pattern 304 when a color unevenness defect occurs, and a stepwise change (gradation) occurs in the color of the image that should be uniform. .

  In the image forming apparatus 10 according to the present embodiment, the detection of the color unevenness defect is performed in the same manner as the detection of the nozzle defect. That is, the color unevenness defect detection pattern 304 printed on the recording paper P together with the image PG to be printed is read by the in-line sensor 80 and sent as image information to the damaged paper determination unit 100B. The damaged paper determination unit 100B compares the image information of the color unevenness defect detection pattern 304 stored in advance in the storage unit 110 and the read image information of the color unevenness defect detection pattern 304 sent from the inline sensor 80. Thus, the presence / absence of color unevenness and the degree of color unevenness are determined. The degree of color unevenness may be, for example, a ratio of deviation from the reference when the initial value of the print density of each color (for example, a value at the time of factory shipment) is used as a reference.

  In addition, according to the color unevenness defect detection pattern 304 according to the present embodiment, an undischarge failure of the nozzle 48a may also be detected. When the color unevenness defect detection pattern 304 according to the present embodiment is printed in a state where a certain nozzle 48a does not discharge, the color unevenness defect detection pattern 304 is a solid pattern, and therefore, as shown in FIG. This is because a white streak S may be generated in a portion corresponding to the nozzle 48a in which the undischarge failure has occurred. Therefore, the color unevenness defect detection pattern 304 may be used as a pattern that complements the nozzle defect detection pattern 302.

  The detection of the color unevenness defect is not limited to the form using the color unevenness detection pattern 304, but instead, a color unevenness detection pattern in which the entire surface of the recording paper P is a solid pattern is used to print one job. It is also possible to print before starting the image, and to detect the defect level of the color unevenness defect from the result.

Next, with reference to FIG. 6, a method for detecting a contamination defect will be described.
For example, when the damaged paper determination unit 100B determines the difference between the image information of the color unevenness defect detection pattern 304 and the read image information on the basis of the difference between them, the stain defect determination unit 100B determines a determination criterion ( For example, it is also detected by using a difference area.
However, in order to detect dirt more reliably, the present embodiment employs a method of detecting using a document image.

  6A shows a recording sheet P (good paper) on which normal printing has been performed, and FIG. 6B shows a recording sheet P (damaged paper) in which a stain defect has occurred due to the stain YG. ). In the detection of a stain defect according to the present embodiment, a stain defect is detected using a difference between the image information of the good paper and the image information of the damaged paper.

  That is, the image information of the print image obtained by converting the image information of the original image sent from the scanner unit 120 by the image processing unit 100A is stored in the RAM 104, for example. On the other hand, the broken paper determination unit 100B that has received the read image information obtained by reading the printed matter printed by the image forming unit 16 using the image information of the print image by the in-line sensor 80 is the image of the print image stored in the RAM 104 or the like. The information is read and compared with the read image information, and a stain defect is detected from the difference. The degree of the stain defect may be, for example, a ratio of the stain area to the print area of the recording paper P.

  In the above-described embodiment, an example in which the nozzle defect and the color unevenness defect are detected using the print defect detection pattern 300 corresponding to the defect to be detected and the stain defect is detected using the document image is exemplified. However, the present invention is not limited to this. For each print defect content, a detection method using a print defect detection pattern 300 and a detection method using a document image may be combined. For example, all defects may be detected by a method using a document image.

Next, with reference to FIG. 7, the relationship between the image quality (print image quality) of the printed matter as the required image quality and the waste paper determination criterion will be described.
In the present embodiment, the waste paper determination criteria are, for example, the print image quality in the descending order of image quality, high image quality,
After classifying into bar code, photograph, map, character, and low image quality, each print image quality is provided as a degree of defect (defect level) classified according to the print defect content.
Note that high image quality is a category when higher image quality than a barcode is required, and low image quality is a category when lower image quality than a character image is allowed.

  FIG. 7A is an example of a determination criterion table showing a correspondence relationship between the print image quality and the waste paper determination criterion according to the present embodiment. The determination criterion table is stored in advance in a storage unit such as the ROM 102, for example. Yes. As an example, the defect level of each print defect content according to the present embodiment is classified into five levels of 1, 2, 3, 4, and 5 from the one with the poorer degree of defect.

In FIG. 7 (a), for example, the barcode is a damaged paper judgment criterion of level 5 for nozzle failure, level 5 for color unevenness failure, and level 4 for stain failure. In addition, for characters, the nozzle defect is level 2, the color unevenness defect is level 2, and the smudge defect is level 2, which is a damaged paper judgment criterion. The same applies to other print image quality (high image quality, photograph, map, low image quality).
In the determination criterion table shown in FIG. 7A, a print image quality of “not determined” is also provided in consideration of versatility when setting the print image quality.

  FIG. 7B shows a determination threshold value for each defect level corresponding to each print defect content. In the figure, as an example, the nozzle failure is the number of defective nozzles, the color unevenness failure is the percentage of deviation from the initial setting expressed as a percentage, and the stain failure is represented by the percentage of stain in the print area of the recording paper P. ing.

  In FIG. 7B, for nozzle defects, the defect level 5 is less than 10 (0 to 9), the defect level 4 is less than 50 (10 to 49), and the defect level 3 is less than 100. (50 to 99), defect level 2 is less than 150 (100 to 149), and defect level 1 is less than 200 (150 to 199). For color unevenness defects, the defect level 5 is less than 1% (0% ≦ color unevenness defect <1%), the defect level 4 is less than 5% (1% ≦ color unevenness defect <5%), and the defect level 3 is Less than 10% (5% ≦ color unevenness defect <10%), defect level 2 is less than 20% (10% ≦ color unevenness defect <20%), and defect level 1 is less than 30% (20% ≦ color unevenness defect < 30%). Further, regarding the stain defect, the defect level 5 is less than 0.1% (0% ≦ dirt defect <0.1%), and the defect level 4 is less than 0.5% (0.1% ≦ dirt defect <0.5). %), Defect level 3 is less than 1.0% (0.5% ≦ dirt defect <1.0%), defect level 2 is less than 1.5% (1.0% ≦ dirt defect <1.5%) The defect level 1 is less than 2.0% (1.5% ≦ dirt defect <2.0%).

  The determination threshold value for the defective level of nozzle failure is not limited to the method represented by the above number, and may be represented, for example, by the ratio of the number of defective nozzles to the total number of nozzles or by the number of defective nozzles per unit area. May be. In addition, the determination threshold value for contamination failure is not limited to the above, and may be expressed by the contamination area per unit area.

  According to the determination threshold value for each print image quality defined as shown in FIG. 7, for example, in the case of a barcode, the determination threshold value for nozzle failure is less than 10 defective nozzles, and the determination threshold value for color unevenness failure is initial. The variation is less than 1% of the value, and the contamination threshold is a stain having an area of less than 0.5% with respect to the area of the print region of the recording paper P. The view of FIG. 7 is the same for other print image quality.

7A is not limited to the above, and may be set in consideration of the degree of influence of each print defect content on each print image quality.
The setting of the determination threshold for each defect level shown in FIG. 7B is also an example, and may be set in consideration of the degree of influence of the defect level on the print image. For example, the setting of the determination threshold value is not limited to five steps as shown in FIG. 7B, and may be four steps or less or six steps or more.

  Next, with reference to FIG. 8, a description will be given of the waste paper determination process executed in the image forming apparatus 10 according to the present embodiment. FIG. 8 is a flowchart showing the flow of processing of the waste paper determination processing program executed by the CPU 100, and the program is stored in storage means such as a predetermined area in the ROM 102.

  Here, when executing the waste paper determination processing program, the program is not limited to a mode in which the program is preinstalled in a storage unit such as the ROM 102, but is provided in a state stored in a computer-readable storage medium. A form distributed via wired or wireless communication means may be applied.

  Further, the waste paper determination processing according to the present embodiment is realized by a software configuration using a computer by executing a program. However, the configuration is not limited to the software configuration, and may be realized by, for example, a hardware configuration employing ASIC (Application Specific Integrated Circuit) or a combination of the hardware configuration and the software configuration.

  In the waste paper determination processing according to the present embodiment, an operator places a document on a document table (not shown) of the scanner unit 120, designates the number of prints from the UI panel 108 or the like, and instructs to start printing. This is done by the CPU 100 reading and executing the waste paper determination processing program from the ROM 102 or the like. Here, it is assumed that the manuscript is placed on the manuscript table and an instruction to start printing is given.

  In FIG. 8, first, in step S100, the scanner unit 120 is controlled to read a document placed on a document table, and in the next step S101, a UI panel 108 is displayed so as to display a pull-down menu having a predetermined print quality. In step S102, input of print image quality is waited. FIG. 9 shows an example of the print quality pull-down menu. In the display of FIG. 9, a print quality pull-down menu is displayed together with a message “Please enter print quality”.

In the next step S104, the waste paper determination criterion corresponding to the print image quality input via the print image quality pull-down menu is read from the storage means such as the ROM 102.
In the next step S106, the image information of the print defect detection pattern 300 is read from a storage unit such as the storage unit 110.

  In the next step S110, the recording head controller 116, the motor controller 118, and the like are controlled so as to start printing a document image.

In the next step S112, the inline sensor 80 is controlled so as to read the print defect detection pattern 300 printed in step S110.
In the next step S114, the image information of the print defect detection pattern 300 read in step S106 is compared with the image information of the printed print defect detection pattern 300 obtained by reading by the inline sensor 80 in step S112. To extract.

As described above, in the present embodiment, in addition to determining the occurrence of damaged paper based on the image of the print defect detection pattern 300, the occurrence of damaged paper may be determined based on the printed image of the document. .
In this case, when starting printing in step S110, the image information of the printed image of the document read by the scanner unit 120 is stored in a storage unit such as the RAM 104. In steps S112 and S114, “printing defect detection pattern” is read as “printed image of document”. More specifically, in step S114, the image information of the printed image of the document stored in RAM 104 or the like in step S110 is compared with the read image information of the document read in step S112, and the difference is extracted. .

  In the next step S116, it is determined based on the difference extracted in step S114 and the loss paper determination criterion shown in FIG. 7 whether or not a loss paper has occurred (that is, whether or not a printing failure has occurred).

  More specifically, for example, when nozzle failure is taken as an example, the number of defective nozzles is obtained from the difference in image information of the print failure detection pattern 300 extracted in step S114. The number and the determination threshold value of the defective nozzle shown in FIG. 7B are compared, and the corresponding defective level is determined. The defect level is compared with the defect level of the nozzle defect corresponding to the print image quality input in step S102. If the former and the latter are the same defect level, or the former is more severe than the latter, the waste paper Has not occurred. On the other hand, if the latter is a stricter defect level than the former, paper loss has occurred.

If a negative determination is made in step S116, the process proceeds to step S118, where it is determined whether printing has been completed. If a negative determination is made, the process returns to step S110 to continue printing.
On the other hand, if the determination in step S118 is affirmative, the process proceeds to step S126 to stop printing, and then the present loss paper determination processing program is terminated.
The determination of the end of printing in step S118 may be made based on, for example, whether or not the number of printed recording sheets P has reached the number of printed sheets input at the start of printing by the operator.

  If the determination in step S116 is affirmative, the process proceeds to step S120, and the stamp unit 126 is controlled to press a stamp indicating that the paper is damaged on the recording paper P determined to be damaged. The stamp may be performed, for example, by attaching a red mark to the edge (outside) of the recording paper P.

In the next step S122, the UI panel 108 or the like is controlled so as to display that the waste paper has occurred, and in the next step S124, the printing is interrupted and the present waste paper determination processing program is terminated.
Note that, in the display of the UI panel 108 in step S122, for example, the contents of defective printing that is the cause of the loss paper, the page where the loss paper is generated, and the like may be displayed.

  As described above in detail, according to the image forming apparatus according to the present embodiment, the frequency with which an image formed on a recording medium is determined to be an image formation defect (damaged paper) is suppressed.

[Second Embodiment]
The broken paper determination processing according to the present embodiment is a mode that takes into account the case where the document is composed of a plurality of different pages in the first embodiment.

  In the waste paper determination processing according to the present embodiment, print image quality is input and specified for each of a plurality of pages of originals. Then, based on the defect level of each print defect content of the print image quality designated for each page, the presence / absence of the occurrence of damaged paper is determined for each page.

  Since the basic flow of the waste paper determination processing program according to the present embodiment is the same as that shown in FIG. 8, only different points will be described with reference to FIG.

In the waste paper determination processing program according to the present embodiment, steps S101 and S102 are performed.
Change to waiting for input of print quality for each page. The display on the UI panel 108 at this time is, for example, the same display as in FIG. 9 and may be changed so that the print image quality is input for each page.

In step S104, a change is made so that the broken paper judgment criterion corresponding to the print image quality input for each page is read.
There is no change in steps S106 to S110. In step S112 and the subsequent steps, the occurrence of lost paper is generated for each page based on the print defect detection pattern 300 read in step S106 and the loss judgment criteria for each page read in step S104. What is necessary is just to change so that the presence or absence may be judged.

As described above, the image forming apparatus according to the present embodiment also suppresses the frequency with which an image formed on a recording medium is determined as an image formation defect (damaged paper).
In the present embodiment, when the document is composed of a plurality of different pages, the loss paper determination process is performed in accordance with the print image quality of each page, and therefore the frequency at which it is determined as a loss paper is further suppressed.

  In the present embodiment, when the document is composed of a plurality of different pages, the print image quality is designated for each page and the loss paper determination process is performed for each page. Not limited. For example, the highest print image quality may be extracted from the print image quality for each designated page, and the loss paper determination process may be performed by applying a loss paper determination criterion corresponding to the extracted print image quality.

[Third Embodiment]
With reference to FIG. 10, the loss paper determination process of the image forming apparatus 10 according to the present exemplary embodiment will be described. The waste paper determination processing according to the present embodiment is not a method of setting the waste paper determination standard by selecting the print image quality in the loss paper determination processing in each of the above embodiments, but a defect level corresponding to each print defect content. A method is adopted that directly sets and sets the judgment criteria for waste paper.
Therefore, an example of the waste paper determination processing program according to the present embodiment is a waiting state in FIG. 8 that waits for the input of the direct paper loss determination criteria in steps S101 and S102.

  FIG. 10 shows an example of the display on the UI panel 108 in the waiting state. In FIG. 10, together with the message “Please enter the numerical value of the defect level of each defect.”, A defect level input window is displayed corresponding to each print defect content.

In the waste paper determination process according to the present embodiment, the operator displays the defect level for the nozzle defect, the defect level for the color unevenness defect, and the defect level for the stain defect in the window shown in FIG. Enter numerical values. Therefore, step S104 in FIG. 8 directly refers to the determination threshold value shown in FIG. 7B stored in the storage means such as the ROM 102 in advance, and sets the determination threshold value corresponding to the defect level of each input print defect content. Changed to read.
After that, based on the defect level corresponding to each print defect content set by the above input,
The waste paper determination process is executed while printing is being performed.

According to the above-described loss paper determination process, the defect level of each print defect content is directly specified without passing through the image quality of the print image, so that the setting of the loss paper determination criterion is made more finely. as a result,
The frequency with which an image formed on a recording medium is determined to be an image formation defect (damaged paper) is further suppressed.

[Fourth Embodiment]
With reference to FIG.11 and FIG.12, the paper loss determination process which concerns on this Embodiment is demonstrated.
The broken paper determination process according to the present embodiment is such that the broken paper determination process is performed even when a plurality of pages of documents with different print image quality are imprinted on a single recording paper P. is there.

  FIG. 11A shows an example in which a four-page document of Page 1 to Page 4 is imposed. The print image quality of each page is set such that Page 1 is high image quality, Page 2 is a photo, Page 3 is not determined, and Page 4 is a map.

  Note that the imposition and print image quality settings in FIG. 11 are merely examples, and the imposition page number setting and the print image quality setting for each page can be variously set according to the content of the document. Good.

In this case, the damaged paper judgment standard for each print defect content for each page of the document is as shown in FIG.
Therefore, in the present embodiment, among the paper loss judgment criteria for the print defect contents for each page of the original, the paper loss judgment criteria for the pages imposed with the strictest paper loss judgment criteria (hereinafter referred to as “total paper loss judgment criteria”). ").
As shown in FIG. 11B, the total waste paper determination criteria in this example are nozzle failure = 5, color unevenness failure = 5, and stain failure = 5.

FIG. 12 is a flowchart showing the flow of processing of the waste paper determination processing program according to the present embodiment.
First, in step S200, the scanner unit 120 is controlled to read a document placed on the document table, and in the next step 201, the UI panel 108 is controlled to display a pull-down menu of a predetermined print quality, In step S202, input of print image quality is waited. In step S203, it is determined that reading of each page has been completed. If the determination is negative, the process returns to step S200 to repeat reading of the original.

In the next step S204, the paper loss criterion corresponding to the print image quality of each page input via the print image quality pull-down menu is read from the storage means such as the ROM 102.
In the next step S206, a comprehensive loss judgment criterion is determined based on the loss judgment criterion for each page input in step S204. In the present embodiment, as described above, the most severe defect level is selected from the defect levels input for each print defect content, and the defect level of each print defect content is determined, which is used as a comprehensive loss judgment criterion. .

  The next steps S208 to S228 are the same as steps S106 to S126 in FIG.

  According to the damaged paper determination processing according to the present embodiment, even for a printed matter in which a plurality of pages are impositioned on a single recording paper P, an image formation defect (damaged paper) with respect to an image formed on a recording medium. It is suppressed the frequency that is determined.

  In each of the above embodiments, when the defect level of each print defect content is detected in job unit printing, the result is not particularly stored, but the detection result of the most recent defect level is lost. You may memorize | store in memory | storage means, such as the memory | storage part 110, before a determination processing program is complete | finished. In this case, for example, when the operator selects the print image quality prior to printing, the stored defect level does not satisfy the condition of the defect level corresponding to the selected print image quality, and the waste paper is If it is predicted that it will occur, printing may be started after performing maintenance.

  In each of the above-described embodiments, an example in which the operator inputs the print image quality prior to printing has been described as an example. However, the present invention is not limited to this. For example, the CPU 100 determines the print image quality based on the density of image information (or image information of the print image of the original read by the scanner unit 120) obtained by reading the printed product of the original print image with the inline sensor 80. You may do it.

DESCRIPTION OF SYMBOLS 10 Image forming apparatus 12 Paper feed conveyance part 14 Processing liquid application part 16 Image formation part 18 Drying part 20 Image fixing part 22 Discharge part 24 Discharge conveyance part 26 Accommodating part 28A thru | or 28E Intermediate conveyance drum 30 Motor 32 Belt 34 Holding member 36 Processing Liquid coating drum 38 Processing liquid coating roller 44 Image forming drum 46 Head unit 48 Inkjet recording head 48a Nozzle 56 Ink drying drum 58 Hot air heater 62 Image fixing drum 64 Fixing roller 68 Discharge transport drum 80 Inline sensor 100 CPU
100A Image processing unit 100B Broken paper determination unit 102 ROM
104 RAM
106 NVM
108 UI panel 110 Storage unit 112 Communication interface 114 Terminal device 116 Recording head controller 118 Motor controller 120 Scanner unit 300 Print defect detection pattern 302 Nozzle defect detection pattern 304 Color unevenness defect detection pattern BUS Bus P Recording paper PG Image S Line YG Dirt

Claims (5)

Forming means for forming an image on a recording medium;
Reading means for reading a formed image that is an image formed on the recording medium by the forming means;
The required image quality that indicates the height of image quality required for the formed image for each predetermined stage, and each of a plurality of types of determination items that are used for determining the quality of the formed image at each required image quality stage. Storage means for preliminarily storing determination criteria required for the determination items corresponding to the required image quality at the corresponding stage;
When the requested image quality at a stage required for a determination target image that is a formed image that is a determination target of the quality is accepted , and the plurality of determination target images are formed on one recording medium, the request A receiving unit that receives image quality for each of the plurality of determination target images, the determination criterion stored in the storage unit corresponding to the stage of the requested image quality received by the receiving unit, and the determination target based on image information and the determination target image showing an image to the difference between the image information obtained by reading by the reading means as said forming an image, along with determining the quality of the determination target image, the plurality by said receiving means When the required image quality is accepted for each of the determination target images, the most severe of the determination criteria corresponding to the required image quality Determination means for determining the quality of the determination target image using the determination criteria ;
An image forming apparatus. Forming means for forming an image on a recording medium;
Reading means for reading a formed image that is an image formed on the recording medium by the forming means;
The required image quality that indicates the height of image quality required for the formed image for each predetermined stage, and each of a plurality of types of determination items that are used for determining the quality of the formed image at each required image quality stage. Storage means for preliminarily storing determination criteria required for the determination items corresponding to the required image quality at the corresponding stage;
When the requested image quality at a stage required for a determination target image that is a formation image to be a quality determination target is received and the determination target image is formed on a plurality of the recording media, the required image quality is Receiving means for receiving each of a plurality of recording media ;
The determination unit stored in the storage unit corresponding to the stage of the requested image quality received by the reception unit, the image information indicating the determination target image, and the determination target image as the formed image as the forming unit If the determination unit determines whether the determination target image is acceptable based on the difference from the image information obtained by reading the image, and the reception unit receives the requested image quality for each of the plurality of recording media, the request A determination unit that determines the quality of the determination target image using the strictest determination criterion among the determination criteria corresponding to image quality;
An image forming apparatus. The image forming apparatus according to claim 1 or claim 2, further comprising display means for displaying a determination result by the determination unit. The receiving unit is an image forming apparatus according to any one of claims 1 to 3 further receives the determination criterion stored in the storage means. Forming means for forming an image on a recording medium;
Reading means for reading a formed image that is an image formed on the recording medium by the forming means;
The required image quality that indicates the height of image quality required for the formed image for each predetermined stage, and each of a plurality of types of determination items that are used for determining the quality of the formed image at each required image quality stage. Storage means for preliminarily storing determination criteria required for the determination items corresponding to the required image quality at the corresponding stage;
A program for controlling an image forming apparatus comprising:
Computer
When the requested image quality at a stage required for a determination target image that is a formed image that is a determination target of the quality is accepted , and the plurality of determination target images are formed on one recording medium, the request A receiving unit that receives image quality for each of the plurality of determination target images, the determination criterion stored in the storage unit corresponding to the stage of the requested image quality received by the receiving unit, and the determination target based on image information and the determination target image showing an image to the difference between the image information obtained by reading by the reading means as said forming an image, along with determining the quality of the determination target image, the plurality by said receiving means When the required image quality is accepted for each of the determination target images, the most severe of the determination criteria corresponding to the required image quality Determination means for determining the quality of the determination target image using the determination criteria ;
Program to function as.