JP2014066865A - Image forming apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an image forming apparatus capable of accurately recognizing time of replacement of units.SOLUTION: An intermediate transfer unit, developing unit, developer, secondary transfer unit, drum unit, and fixing unit comprise functions related to image formation and are configured to be removably attached to an image forming apparatus. An image pickup unit 60 is provided on a conveyance unit 420 where a sheet is conveyed on which an image is formed by an image forming unit 41, and reads the image on the sheet conveyed on the conveyance unit 420. A control unit 110 compares read image data obtained by reading the image by the image pickup unit 60 with original image data that is the original of the image formed by the image forming unit 41 to determine the phenomenon occurring to the image formed on the sheet. The control unit 110 determines whether the intermediate transfer unit, developing unit, developer, secondary transfer unit, drum unit, and fixing unit have reached the time of replacement on the basis of a determination result.

Description

  The present invention relates to an image forming apparatus.

  2. Description of the Related Art Conventionally, there has been known an image forming apparatus including a detachable unit in which a plurality of replaceable parts are grouped. In such an image forming apparatus, when a certain part reaches the end of its life or a failure occurs, a unit on which the corresponding part is mounted is pulled out of the image forming apparatus and replaced with a new one.

  In recent years, in order to suppress downtime, an image forming apparatus that can replace a unit by itself without waiting for a service person has been proposed.

  In order to inform the user of the unit replacement time, the operation counter is counted along with the operation of the image forming apparatus, and when the operation counter value reaches a certain value, the replacement time is notified. There is a thing (for example, patent document 1).

JP 2010-139768 A

  However, the operation counter in the technique described in Patent Document 1 is only a guide for unit replacement, and cannot accurately determine the unit replacement time. That is, the degree of deterioration of the unit may change depending on the installation conditions of the image forming apparatus, and the unit may not deteriorate at all even if the operation counter value becomes a constant value. In such a case, urging replacement of the unit leads to replacement of a unit that is still sufficiently usable, and there is a problem that the unit cannot be used up sufficiently and costs are increased.

  An object of the present invention is to provide an image forming apparatus that can accurately grasp the replacement time of a unit.

In order to solve the above problems, the invention according to claim 1 is an image forming apparatus comprising:
An image forming unit for forming an image on paper;
A detachable unit having functions relating to image formation;
A reading unit that is provided on a conveyance unit to which a sheet on which an image is formed by the image forming unit is conveyed, and that reads an image of the sheet conveyed on the conveyance unit;
A phenomenon that occurs in an image formed on the sheet by comparing read image data obtained by reading an image with the reading unit and original image data that is an original of an image formed by the image forming unit. A control unit that determines whether or not the unit is at a replacement time based on the determination result;
It is provided with.

According to a second aspect of the present invention, in the image forming apparatus according to the first aspect,
An image reading unit that reads the image and obtains the original image data;
The image forming unit forms an image on a sheet based on the original image data obtained by the image reading unit;
The control unit compares the original image data obtained by the image reading unit and the read image data to determine a phenomenon occurring in the image formed on the paper.

According to a third aspect of the present invention, in the image forming apparatus according to the first aspect,
The image forming unit forms an image on a sheet based on image data included in a print job input from the outside,
The control unit compares the original image data, which is image data included in the print job, with the read image data, and determines a phenomenon occurring in the image formed on the paper.

According to a fourth aspect of the present invention, in the image forming apparatus according to any one of the first to third aspects,
The reading unit reads an image by capturing an image formed on the paper.

According to a fifth aspect of the present invention, in the image forming apparatus according to any one of the first to fourth aspects,
A display unit for displaying predetermined information;
The control unit displays on the display unit that the unit is in a replacement time when it is determined that the unit is in a replacement time.

According to a sixth aspect of the present invention, in the image forming apparatus according to any one of the first to fifth aspects,
An informing unit for informing predetermined information;
When the unit that has not been determined to be the replacement time is removed, the control unit causes the notification unit to notify that the unit is not at the replacement time.

According to a seventh aspect of the present invention, in the image forming apparatus according to any one of the first to fifth aspects,
A unit lock for locking the attachment and detachment of the unit;
The control unit releases the lock of the unit by the unit lock unit when it is determined that it is time to replace the unit.

The invention according to claim 8 is the image forming apparatus according to any one of claims 1 to 7,
The reading unit is a first reading unit,
A second reading unit that reads an image of a sheet conveyed on the conveyance unit at a position different from the first reading unit on the conveyance unit;
The control unit compares the first read image data obtained by reading the image with the first reading unit and the second read image data obtained by reading the image with the second reading unit, thereby comparing the paper. It is characterized in that a phenomenon occurring in the image formed above is determined.

  According to the present invention, it is possible to accurately grasp the unit replacement time.

1 is a diagram illustrating an internal configuration of an image forming apparatus according to a first embodiment. It is a figure explaining the internal structure of an image formation part. 2 is a block diagram illustrating a functional configuration of the image forming apparatus. FIG. It is a flowchart explaining an image analysis process. It is a figure explaining a difference image. It is a figure explaining a cause coefficient table. It is a figure explaining an exchangeable threshold table. It is a figure explaining the ORU-M exchange display process which concerns on 1st Embodiment. It is a block diagram explaining the functional structure of a control part. FIG. 6 is a block diagram illustrating a functional configuration of an image forming apparatus according to a second embodiment. It is a flowchart explaining the ORU-M exchange process which concerns on 2nd Embodiment. It is a block diagram which shows the functional structure of the image forming apparatus which concerns on 3rd Embodiment. It is a flowchart explaining the ORU-M exchange process which concerns on 3rd Embodiment. It is a figure which shows the internal structure of the other example of an image forming apparatus. It is a figure which shows the internal structure of the other example of an image forming apparatus.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. The scope of the invention is not limited to the illustrated example.

(First embodiment)
The image forming apparatus 1 according to the first embodiment includes, for example, an image reading unit 20, an image forming unit 41, a paper feeding unit 50, and an image capturing unit 60, as shown in FIG.

  The image reading unit 20 includes an automatic document feeder (ADF: Auto Document Feeder), a platen glass, a CCD (Charge Coupled Device) 21, and a light source. Then, the image reading unit 20 forms an image by the CCD 21 and photoelectrically converts the reflected light of the light that has been illuminated and scanned with respect to the document supplied from the light source by the ADF or the document set at a predetermined position. The image is read as R, G, and B signals, and the read analog image signal is converted into R, G, and B image data and output.

  The output image data undergoes predetermined image processing, is converted into YMCK data, and is sent to the image forming unit 41.

  The image forming unit 41 includes a plurality of sets of image forming units 40Y, 40M, 40C, and 40K, an endless intermediate transfer belt 407, a transport unit 420 that transports the fed paper, and toner transferred to the paper. And a fixing unit 413 for fixing the image.

  The image forming unit 40Y for forming a yellow (Y) image includes a photosensitive drum 401Y as an image carrier, a developing unit 402Y, a charger 403Y disposed around the photosensitive drum 401Y, and a laser unit 404Y. And a cleaner 405Y and a primary transfer roller 406Y.

  Similarly, the image forming unit 40M that forms a magenta (M) color image includes a photosensitive drum 401M, a developing device 402M, a charger 403M, a laser unit 404M, a cleaner 405M, and a primary transfer roller 406M. I have.

  Similarly, the image forming unit 40C for forming a cyan (C) color image includes a photosensitive drum 401C, a developing unit 402C, a charger 403C, a laser unit 404C, a cleaner 405C, and a primary transfer roller 406C. I have.

  Similarly, the image forming unit 40K that forms a black (K) image includes a photosensitive drum 401K, a developing unit 402K, a charging unit 403K, a laser unit 404K, a cleaner 405K, and a primary transfer roller 406K. I have.

  Here, an image forming operation in the image forming unit 41 will be described. First, in the image forming unit 40Y, the photosensitive drum 401Y rotates, the surface thereof is charged by the charger 403Y, and the latent image of the Y data image is formed on the charged portion by the exposure of the laser light source output from the laser unit 404Y. It is formed. The latent image portion is developed by the developing device 402Y to form a yellow toner image. The toner image is primarily transferred to the intermediate transfer belt 407 by the pressure contact of the primary transfer roller 406Y. The toner image is a yellow image corresponding to the image data to be output. The toner that has not been primarily transferred is removed by the cleaner 405Y.

  Similarly, in the image forming units 40M, 40C, and 40K, magenta toner images, cyan toner images, and black toner images are formed and transferred, respectively. The image forming unit 41 further includes a roller 408, a secondary transfer roller 410, and an intermediate transfer belt by rotation of the roller 408, the secondary transfer roller 410, and the primary transfer rollers 406Y, 406M, 406C, 406K. 407 is circulated. As the intermediate transfer belt 407 is circulated, YMCK toner images are sequentially superimposed and transferred onto the intermediate transfer belt 407.

The paper feed unit 50 includes paper feed trays 500A, 500B, and 500C, and paper feed rollers 501A, 501B, and 501C for transporting paper set in the paper feed trays 500A to 500C to the transport unit 420.
When the image forming unit 41 forms an image on a sheet, the sheet is conveyed one by one from any of the sheet feeding trays 500A to 500C by rotation of any of the sheet feeding rollers 501A to 501C. It is conveyed to the secondary transfer roller 410 by the rotation of the registration roller 409.

  When the sheet passes through the pressure contact portion of the secondary transfer roller 410, the YMCK toner image on the intermediate transfer belt 407 is secondarily transferred to the sheet. The sheet on which the YMCK toner image is transferred passes through the fixing unit 413. By the pressurization and heating of the fixing unit 413, the YMCK toner image is fixed on the paper to form a color toner image. The paper on which the image is formed is discharged by a paper discharge roller 417.

  When forming an image on both sides, a sheet on which an image is formed on one side (front side) is sent to the duplex conveyance unit 415 by the conveyance path switching plate 414 and the surface is reversed by the duplex conveyance unit 415. Then, the sheet is conveyed to the secondary transfer roller 410 by the registration roller 409 so that the image is formed again on the surface where the image is not formed (back surface), and the image is formed. The paper on which images are formed on both sides and the toner is fixed is conveyed to a paper discharge tray 419 by a paper discharge roller 417. In the present embodiment, a flow path through which a sheet is conveyed by the registration roller 409, the secondary transfer roller 410, the duplex conveyance unit 415, the discharge roller 417, and the like is referred to as a conveyance unit 420.

  After the image formation on the paper, the toner remaining on the intermediate transfer belt 407 is removed by the belt cleaning 412. Further, a positive polarity current and a negative polarity current are alternately switched from a power source (not shown) to the secondary transfer roller 410 and flow for a predetermined time, so that the toner remaining on the secondary transfer roller 410 is transferred to the intermediate transfer belt 407. The transfer is performed again, and the secondary transfer roller 410 is cleaned.

  The image capturing unit 60 as a reading unit includes a CCD, and is provided above the transport unit 420. The image capturing unit 60 is configured to read an image formed on a sheet that passes through the fixing unit 413 and is fed in the direction of the sheet discharge roller 417 by the conveyance path switching plate 414. For example, the image capturing unit 60 extends in the main scanning direction orthogonal to the paper conveyance direction, and can read an image in the main scanning direction at a time. The image capturing unit 60 uses a CCD, but other image capturing devices such as a CMOS (Complementary Metal Oxide Semiconductor) image sensor may be employed. In addition to the imaging device as described above, a light receiving element such as an IDC (Image Density Control) sensor or a photodiode may be used.

  In the present embodiment, the image forming unit 41 includes a plurality of detachable units having functions relating to image formation, as shown in FIG. These units include, for example, an intermediate transfer unit 41a, a developing unit 41b, a secondary transfer unit 41c, a drum unit 41d, and a fixing unit 41e. The intermediate transfer unit 41a is a unit in which a plurality of components such as an intermediate transfer belt 407 and a roller 408 are unitized. The developing unit 41b is provided for each of a plurality of sets of image forming units 40Y, 40M, 40C, and 40K, and a plurality of parts such as the developing devices 402Y, 402M, 402C, and 402K are unitized. The secondary transfer unit 41c is a unit in which a plurality of components such as the secondary transfer roller 410 are unitized. The drum unit 41d is provided for each of a plurality of sets of image forming units 40Y, 40M, 40C, and 40K. The drum unit 41d is obtained by unitizing a plurality of components such as the photosensitive drums 401Y, 401M, 401C, and 401K. The fixing unit 41e is a unit in which a plurality of parts such as the fixing unit 413 are unitized. The intermediate transfer unit 41a, the developing unit 41b, the secondary transfer unit 41c, the drum unit 41d, and the fixing unit 41e can be replaced by a user using the image forming apparatus 1 (ORU-M: Operator Replaceable Unit-Management). Thus, downtime is reduced and service costs are reduced. In addition, the form of the unit employed in the present embodiment is not limited to the above-described form, and can be set as appropriate.

Next, the configuration of the control system of the image forming apparatus 1 will be described.
As shown in FIG. 3, the image forming apparatus 1 includes a main body 1a and a printer controller 1b. Further, the image forming apparatus 1 is connected to an external device (PC) 2 on the network 3 through a LANIF (Local Area Network InterFace) 14 of the printer controller 1b so as to be able to transmit and receive data to and from each other.

  The main body 1a includes an image reading unit 20, an operation display unit 30, a printing unit 40, an image capturing unit 60, and an image control board 100. In addition, the same code | symbol is attached | subjected to the structure same as each part demonstrated in FIG. 1, and the description is abbreviate | omitted.

  The image control board 100 includes a control unit 110, a nonvolatile memory 120, a RAM (Random Access Memory) 130, a reading processing unit 140, a compression IC 150, a DRAM (Dynamic Random Access Memory) control IC 160, an image memory 170, a decompression IC 180, and a writing process. The unit 190 is provided.

  The control unit 110 reads out various programs and various data stored in the nonvolatile memory 120 and develops them in the RAM 130, and centrally controls each part of the image forming apparatus 1 in cooperation with the program developed in the RAM 130.

The nonvolatile memory 120 includes, for example, a ROM that is a program memory, and stores various processing programs and data related to image formation. Specifically, the nonvolatile memory 120, for example, an image analysis program for analyzing an image formed on a sheet and determining the replacement time of the unit described above, or an ORU-M for displaying a replaceable unit. Various processing programs such as an exchange display program, and various data tables such as a later-described cause coefficient table and an exchangeable threshold table are stored.
The nonvolatile memory 120 includes, for example, an HDD (Hard Disk Drive), and stores data related to a reserved print job, various conditions for job execution, and the like.

  The RAM 130 functions as a work area that temporarily stores various programs executed by the control unit 110, various data related to these programs, print jobs, and the like.

  The reading processing unit 140 performs various processing such as analog processing, A / D conversion processing, shading processing, and the like on the analog image signal input from the CCD 21 of the image reading unit 20, and then generates digital image data. The generated image data is output to the compression IC 150.

  The compression IC 150 performs compression processing on the input digital image data and outputs it to the DRAM control IC 160.

  The DRAM control IC 160 controls the image data compression processing by the compression IC 150 and the decompression processing of the compressed image data by the decompression IC 180 in accordance with instructions from the control unit 110, and performs input / output control of image data to the image memory 170. For example, when an instruction to store the image signal read by the image reading unit 20 is given, the compression processing of the image data input from the reading processing unit 140 is executed by the compression IC 150, and the compressed image data is compressed in the image memory 170. It is stored in the memory 171.

  When printing of compressed image data stored in the compression memory 171 is instructed, the compressed image data is read from the compression memory 171, decompressed by the decompression IC 180, and stored in the page memory 172. Further, when an instruction to print out the image data stored in the page memory 172 is given, the composite image data is read from the page memory 172 and output to the writing processing unit 190.

The image memory 170 includes a compression memory 171 composed of DRAM and a page memory 172. The compression memory 171 is a memory for storing compressed image data, and the page memory 172 is a memory for temporarily storing image data for print output.
In the present embodiment, the page memory 172 can store image data of an image read by the image capturing unit 60, as will be described later.

  The decompression IC 180 performs decompression processing on the compressed image data.

  The writing processing unit 190 generates data for image formation based on the image data input from the DRAM control IC 160 and outputs the data to the printing unit 40.

  The image reading unit 20 includes a CCD 21, an image reading control unit 22, and the like. The image reading control unit 22 performs exposure scanning of the document surface and causes the CCD 21 to perform photoelectric conversion of reflected light to read an image. The read analog image signal is output to the reading processing unit 140.

The operation display unit 30 includes an LCD (Liquid Crystal Display) 31, an operation display control unit 32, and other operation key groups such as a numeric keypad.
The operation display control unit 32 causes the LCD 31 to display various screens for inputting various setting conditions, various processing results, and the like in accordance with a display signal input from the control unit 110. In addition, the operation display control unit 32 outputs operation signals input from various switches, buttons, numeric keys, operation key groups, and a touch panel to the control unit 110.

The print unit 40 includes various units related to print output, such as the image forming unit 41 shown in FIG.
The print control unit 42 controls the operation of each unit of the print unit 40 such as the image forming unit 41 according to an instruction from the control unit 110, and forms an image on a sheet based on the image data input from the writing processing unit 190. Make it.

  The image capturing unit 60 converts a signal obtained by reading an image into image data, and outputs the image data to the control unit 110. The control unit 110 stores the image data output from the image capturing unit 60 in the page memory 172 of the image memory 170.

Next, each part of the printer controller 1b will be described.
The printer controller 1b manages and controls print jobs input from the external device 2 connected to the network 3 to the image forming device 1 when the image forming device 1 is used as a network printer. The data to be printed is received from No. 2, and this data is transmitted as a print job to the main unit 1a.

  The printer controller 1b includes a controller control unit 11, a DRAM control IC 12, an image memory 13, and a LANIF 14.

  The controller control unit 11 comprehensively controls the operation of each unit of the printer controller 1b, and transmits data input from the external device 2 to the main body unit 1a via the LANIF 14 as a print job.

  The DRAM control IC 12 controls storage of data received by the LANIF 14 in the image memory 13 and reading of data from the image memory 13. The DRAM control IC 12 is connected to the DRAM control IC 160 of the image control board 100 via a PCI (Peripheral Components Interconnect) bus, and reads data to be printed from the image memory 13 in accordance with an instruction from the controller control unit 11. Output to the control IC 160.

  The image memory 13 is composed of a DRAM, and temporarily stores input output data.

  The LANIF 14 is a communication interface for connecting to a network 3 such as a network interface card (NIC) or a modem such as a modem, and receives data from the external device 2. The received data is output to the DRAM control IC 12.

  Next, image analysis processing executed by the control unit 110 in the image forming apparatus 1 configured as described above will be described with reference to FIG. This image analysis process can be realized by executing the above-described image analysis program. Also, this image analysis process is a process that is executed, for example, every time an image is formed on a sheet a predetermined number of times. The image analysis process may be executed every time an image is formed on a sheet.

  First, the control unit 110 forms an image on a sheet based on the image data of the image read by the image reading unit 20 or the image data included in the print job received from the external device 2 (step S101). The image formed above is read by the image pickup unit 60, and the image data of the read image is stored in the page memory 172 (step S102).

  The control unit 110 reads the image data (original image data) of the image formed on the paper and the image data (read image data) of the image read by the image capturing unit 60 from the page memory 172, and sets the image quality for each. Image quality correction for matching is performed (step S103). The image quality correction is, for example, adjustment of color temperature or hue. The control unit 110 extracts a difference image by obtaining a difference between the original image data subjected to image quality correction and the read image data (step S104). For example, the control unit 110 first performs image quality correction on the read image data shown in FIG. 5A to obtain image data as shown in FIG. 5B. Further, the control unit 110 performs image quality correction on the original image data shown in FIG. 5C to obtain image data as shown in D of FIG. The control unit 110 obtains the difference between the image data subjected to these image quality corrections, and extracts the difference image data indicated by E in FIG.

  The control unit 110 analyzes the extracted difference image data according to a predetermined algorithm (step S105). Specifically, the control unit 110 analyzes the difference image data and determines a phenomenon occurring in the image formed on the sheet. This phenomenon is an undesirable phenomenon such as a wrinkle generated on a sheet, vertical stripes, horizontal stripes, a color density defect that is an insufficient toner density, or a color shift in which the toner formation position is shifted. These phenomena can be determined by a technique such as pattern matching, for example. When such a phenomenon occurs, the above-described unit may be consumed and it is time to replace it. In the present embodiment, by analyzing the difference image data and determining such a phenomenon, it is possible to determine the unit that has reached the replacement time. Note that the types of phenomena to be determined are not limited to those described above, and can be set as appropriate. And the control part 110 gives a score for every phenomenon as a determination result of a phenomenon. The score is assigned in the range of 0 to 20, and the higher the correlation between the difference image and the phenomenon, the higher the score.

  After analyzing the differential image data as described above, the control unit 110 calculates an evaluation value indicating the evaluation for each unit based on the analysis result (step S106). Specifically, the control unit 110 refers to a cause coefficient table as shown in FIG. 6 stored in the nonvolatile memory 120. The control unit 110 multiplies the score for each phenomenon by the cause coefficient set for each phenomenon, and calculates the total for each unit. For example, when the score of the phenomenon is “wrinkle: 10, vertical stripe: 15, horizontal stripe: 5, color density defect: 0, color misregistration: 0”, the evaluation value of the intermediate transfer unit 41a is 10 × 0. 2 + 15 × 0.2 + 5 × 0.1 + 0 × 0.1 + 0 × 0.1 = 5.5. The evaluation value of the developing unit 41b is 10 × 0 + 15 × 0 + 5 × 0 + 0 × 0.3 + 0 × 0 = 0. The evaluation value of the developer (not shown) is 10 × 0 + 15 × 0 + 5 × 0 + 0 × 0.3 + 0 × 0 = 0. The evaluation value of the secondary transfer unit 41c is 10 × 0.2 + 15 × 0 + 5 × 0 + 0 × 0 + 0 × 0.3 = 2. The evaluation value of the drum unit 41d is 10 × 0.2 + 15 × 0.2 + 5 × 0.2 + 0 × 0.2 + 0 × 0.1 = 6. The evaluation value of the fixing unit 41e is 10 × 0.2 + 15 × 0.1 + 5 × 0.1 + 0 × 0.3 + 0 × 0 = 4. For this evaluation value, an average of the evaluation value calculated before the previous time is obtained and used, but the calculated value may be used each time. Alternatively, the sum of the values calculated before the previous time may be obtained and used.

  Next, as a result of calculating the evaluation value, the control unit 110 determines whether or not the evaluation value of the intermediate transfer unit 41a exceeds a replaceable threshold (step S107). Specifically, for example, the replaceable threshold value for each unit can be obtained by referring to the replaceable threshold table shown in FIG. 7 stored in the nonvolatile memory 120. When the control unit 110 determines that the evaluation value of the intermediate transfer unit 41a exceeds the replaceable threshold (step S107: Y), information indicating that the intermediate transfer unit 41a is a replaceable unit is stored in a predetermined amount of the RAM 130. Store in the storage area (step S108). On the other hand, when the control unit 110 does not determine that the evaluation value of the intermediate transfer unit 41a exceeds the replaceable threshold (step S107: N), the RAM 130 stores information indicating that the intermediate transfer unit 41a is a non-replaceable unit. Is stored in a predetermined storage area (step S109).

  Next, the control unit 110 determines whether or not the evaluation value of the developing unit 41b exceeds the replaceable threshold (step S110). When the control unit 110 determines that the evaluation value of the developing unit 41b exceeds the replaceable threshold (step S110: Y), information indicating that the developing unit 41b is a replaceable unit is stored in a predetermined storage area of the RAM 130. (Step S111). On the other hand, when the controller 110 does not determine that the evaluation value of the developing unit 41b exceeds the replaceable threshold (step S110: N), information indicating that the developing unit 41b is a non-replaceable unit is stored in the RAM 130. (Step S112).

  Next, the control unit 110 determines whether or not the developer evaluation value exceeds a replaceable threshold (step S113). When determining that the developer evaluation value exceeds the replaceable threshold (step S113: Y), the control unit 110 stores information indicating that the developer is a replaceable unit in a predetermined storage area of the RAM 130. (Step S114). On the other hand, when the controller 110 does not determine that the evaluation value of the developer exceeds the replaceable threshold (step S113: N), information indicating that the developer is a non-replaceable unit is stored in the RAM 130 in a predetermined manner. Store in the area (step S115).

  Next, the control unit 110 determines whether or not the secondary transfer unit 41c exceeds a replaceable threshold (step S116). When the controller 110 determines that the secondary transfer unit 41c exceeds the replaceable threshold (step S116: Y), information indicating that the secondary transfer unit 41c is replaceable is stored in a predetermined storage area of the RAM 130. (Step S117). On the other hand, when the control unit 110 does not determine that the evaluation value of the secondary transfer unit 41c exceeds the replaceable threshold (step S116: N), information indicating that the secondary transfer unit 41c is a non-replaceable unit. Is stored in a predetermined storage area of the RAM 130 (step S118).

  Next, the control unit 110 determines whether or not the drum unit 41d exceeds a replaceable threshold (step S119). When it is determined that the drum unit 41d exceeds the replaceable threshold (step S119: Y), the control unit 110 stores information indicating that the drum unit 41d is replaceable in a predetermined storage area of the RAM 130 (step S120). ). On the other hand, when the controller 110 does not determine that the evaluation value of the drum unit 41d exceeds the replaceable threshold (step S119: N), information indicating that the drum unit 41d is a non-replaceable unit is stored in the RAM 130 in a predetermined storage. Store in the area (step S121).

  Next, the control unit 110 determines whether or not the fixing unit 41e exceeds the replaceable threshold (step S122). When determining that the fixing unit 41e exceeds the replaceable threshold (step S122: Y), the control unit 110 stores information indicating that the fixing unit 41e is replaceable in a predetermined storage area of the RAM 130. (Step S123), the process ends. On the other hand, if the control unit 110 does not determine that the evaluation value of the fixing unit 41e exceeds the replaceable threshold (step S122: N), information indicating that the fixing unit 41e is a non-replaceable unit is stored in the RAM 130 in advance. (Step S124), and this process is terminated.

  Next, the ORU-M exchange display process executed by the control unit 110 will be described with reference to FIG. This ORU-M exchange display process is a process executed when, for example, an ORU-M exchange mode executed by a user operating a predetermined operation key of the operation display unit 30 is entered. Note that the control unit 110 performs control so that the user can replace the unit when the ORU-M replacement mode is set.

  First, the control unit 110 determines a replaceable unit with reference to the RAM 130 (step S201). Specifically, the control unit 110 refers to a predetermined storage area of the RAM 130 as described above, and the intermediate transfer unit 41a, the developing unit 41b, the developer, the secondary transfer unit 41c, the drum unit 41d, and the fixing unit 41e. For each of these, it is determined whether or not there is information indicating that the exchange is possible.

  The control unit 110 displays the determination result of the replaceable unit on the LCD 31 of the operation display unit 30 (step S202). For example, the control unit 110 displays the above-described list of units on the LCD 31 and, for a unit in which information indicating that the unit can be replaced is not stored in the RAM 130, that is, a unit that cannot be replaced, displays the unit display. Is grayed out to indicate that it cannot be replaced. By performing such display, it is possible to easily identify the unit that is the replacement time.

  Next, the control unit 110 determines whether or not the ORU-M exchange mode has ended (step S203). When it is not determined that the ORU-M exchange mode has ended (step S203: N), the controller 110 determines whether or not the unit has been replaced (step S204). On the other hand, when it is determined that the ORU-M exchange mode has ended (step S203: Y), the control unit 110 ends this process.

  When it is determined in step S204 that the unit has been replaced (step S204: Y), the control unit 110 resets the evaluation value of the replaced unit (step S205), and then executes the process of step S201. On the other hand, when it is not determined that the unit has been replaced (step S204: N), the control unit 110 executes the process of step S201 without executing the process of step S205.

  The process of determining the unit replacement time by the image forming apparatus 1 configured as described above is roughly as follows.

  That is, for example, as shown in FIG. 9, when image data is input from the external device 2 and an image is formed on a sheet based on the input image data, the image data from the external device 2 is Stored in the page memory 172.

  When an image is formed on a sheet based on the image data stored in the page memory 172, the image capturing unit 60 reads the image formed on the sheet conveyed on the conveyance unit 420. The image read by the image capturing unit 60 is converted into read image data and stored in the page memory 172.

  The control unit 110 includes image quality correction units 110a and 110b, a difference extraction unit 110c, a difference cause analysis unit 110d, an evaluation value calculation unit 110e, a threshold comparison unit 110f, and a replacement display determination unit 110g.

  The image quality correction unit 110a reads the original image data from the page memory 172, and corrects the image quality as described above. Further, the image quality correction unit 110b reads the read image data from the page memory 172, and corrects the image quality as described above.

  The difference extraction unit 110c obtains difference image data as described above from the original image data and the read image data that have been subjected to image quality correction. The difference cause analysis unit 110d analyzes the difference image data as described above and determines a phenomenon occurring in the image formed on the sheet.

  The evaluation value calculation unit 110e refers to the cause coefficient table stored in the nonvolatile memory 120, and calculates the evaluation value for each unit based on the analysis result of the difference image data as described above. Then, the evaluation value calculation unit 110e stores the calculated evaluation value for each unit in the RAM 130.

  The threshold value comparison unit 110f refers to the replaceable threshold value table stored in the nonvolatile memory 120, reads the evaluation value stored in the RAM 130, compares the evaluation value with the replaceable threshold value for each unit, and the evaluation value is exchanged. It is determined whether or not a possible threshold is exceeded. Then, the threshold value comparison unit 110f stores the determination result in the RAM 130.

  When the exchange display determination unit 110g enters the ORU-M exchange mode by the operation of the operation display unit 30, an exchange trigger is input from the operation display unit 30. When the replacement trigger is input, the replacement display determination unit 110g reads the evaluation value determination result for each unit from the RAM 130. The exchange display determination unit 110g outputs exchangeability information to the operation display unit 30 from the evaluation value determination result for each unit. Then, the operation display unit 30 displays the determination result of the replaceable unit on the LCD 31 as described above.

(Second Embodiment)
The image forming apparatus 1 according to the second embodiment is the same as the image forming apparatus 1 according to the first embodiment, except that, for example, as shown in FIG. Therefore, the same components as those of the image forming apparatus 1 according to the first embodiment are denoted by the same reference numerals, and the description thereof is omitted.

  When the unit that cannot be exchanged is removed, the notification unit 70 notifies the fact by voice. Thus, the user can easily recognize this when attempting to replace a unit that is not to be replaced. In addition, the alerting | reporting part 70 may alert | report by not only what performs alerting | reporting by an audio | voice but by display by a display apparatus and light-emitting bodies, such as LED.

  Next, the ORU-M exchange process executed by the control unit 110 in the image forming apparatus 1 configured as described above will be described with reference to FIG. This ORU-M exchange process is a process executed when the ORU-M exchange mode is executed, for example, when the user operates a predetermined operation key of the operation display unit 30. Note that the control unit 110 performs control so that the user can replace the unit when the ORU-M replacement mode is set.

  First, the control unit 110 determines whether it is detected that the unit has been removed (step S301). Whether or not the unit has been removed is determined by, for example, providing a switch for detecting that the unit has been removed and outputting a detection signal thereof. When the unit is removed, a signal is sent from the switch to the control unit 110. This can be done by inputting to. When it is determined that the unit has been removed (step S301: Y), the control unit 110 refers to the RAM 130 to determine a replaceable unit (step S302). Specifically, the control unit 110 determines whether there is information indicating that the removed unit is replaceable. On the other hand, when it is not determined that the unit has been removed (step S301: N), the control unit 110 ends this process.

  The control unit 110 determines whether or not the removed unit is a replaceable unit (step S303). When it is determined that the removed unit is a replaceable unit (step S303: Y), the control unit 110 determines whether the unit has been replaced (step S304).

  When it is determined that the unit has been replaced (step S304: Y), the control unit 110 resets the evaluation value of the replaced unit (step S305), and then executes the process of step S301. On the other hand, when it is not determined that the unit has been exchanged (step S304: N), the control unit 110 executes the process of step S301 without executing the process of step S305.

  Further, when the controller 110 does not determine in step S303 that the removed unit is a replaceable unit (step S303: N), after the warning sound is output by the notification unit 70 (step S306). Then, the process of step S301 is executed.

(Third embodiment)
The image forming apparatus 1 according to the third embodiment is the same as the image forming apparatus 1 according to the first embodiment, for example, except that a unit lock unit 71 is provided as shown in FIG. Therefore, the same components as those of the image forming apparatus 1 according to the first embodiment are denoted by the same reference numerals, and the description thereof is omitted.

  The unit lock portion 71 changes between a state in which removal of a detachable unit is prevented and a state in which it is allowed. Thereby, for example, since it is possible to prevent a user from replacing a unit that is not replaced, it is possible to prevent the unit from being erroneously replaced.

  Next, the ORU-M exchange process executed by the control unit 110 in the image forming apparatus 1 configured as described above will be described with reference to FIG. This ORU-M exchange process is a process executed when the ORU-M exchange mode is executed, for example, when the user operates a predetermined operation key of the operation display unit 30.

  First, the control unit 110 determines a replaceable unit with reference to the RAM 130 (step S401). Specifically, the control unit 110 refers to a predetermined storage area of the RAM 130 as described above, and the intermediate transfer unit 41a, the developing unit 41b, the developer, the secondary transfer unit 41c, the drum unit 41d, and the fixing unit 41e. For each of these, it is determined whether or not there is information indicating that the exchange is possible.

  Next, the control unit 110 controls the unit lock unit 71 to unlock the unit determined to be replaceable (step S402). That is, the unit that cannot be replaced is not unlocked, so that the unit can be prevented from being inadvertently replaced.

  The control unit 110 determines whether or not the ORU-M exchange mode has ended (step S403). When it is not determined that the ORU-M exchange mode has ended (step S403: N), the controller 110 determines whether or not the unit has been replaced (step S404).

  When determining that the unit has been replaced (step S404: Y), the control unit 110 resets the evaluation value of the replaced unit (step S405), and then executes the process of step S403. On the other hand, when it is not determined that the unit has been replaced (step S404: N), the control unit 110 executes the process of step S403 without executing the process of step S405.

  Further, when it is determined in step S403 that the ORU-M exchange mode has ended (step S403: Y), the control unit 110 locks the unit (step S406), and then ends this process.

  In the above-described embodiment, image data obtained from the image reading unit 20 or the external device 2 is used as original image data, and image data read by the image capturing unit 60 is compared as read image data. Although the unit that is the time is determined, the method for determining the unit that is the replacement time is not limited to this. For example, as illustrated in FIG. 14, the second image capturing unit 61 that reads an image formed on a sheet transported to the transport unit 420 at a position different from the image capturing unit 60 on the transport unit 420. You may make it provide. The second image capturing unit 61 is configured by an image capturing device such as a CCD, for example, and is disposed between the secondary transfer roller 410 and the fixing unit 413. Then, the read image data of the image read by the second image pickup unit 61 (second read image data) is compared with the read image data of the image read by the image pickup unit 60 (first read image data). Then, the unit that is the replacement time may be determined. Thereby, for example, it is possible to easily determine whether or not the unit between the image capturing unit 60 and the second image capturing unit 61 is in the replacement period.

  Further, for example, as shown in FIG. 15, in place of the second image capturing unit 61, a reading unit 62 including a light receiving element such as an IDC sensor or a photodiode is provided, and an image read signal and image capturing by the reading unit 62 are provided. The unit that is the replacement time may be determined by comparing the read image data of the image read by the unit 60.

  As described above, according to the first to third embodiments, the image forming unit 41 forms an image on a sheet. The intermediate transfer unit 41a, the developing unit 41b, the developer, the secondary transfer unit 41c, the drum unit 41d, and the fixing unit 41e are configured to be detachable with functions relating to image formation. The image capturing unit 60 is provided on the transport unit 420 to which the paper on which the image is formed by the image forming unit 41 is transported, and reads an image of the paper transported on the transport unit 420. The control unit 110 compares the read image data obtained by reading the image with the image capturing unit 60 with the original image data that is the basis of the image formed by the image forming unit 41, and is formed on the sheet. Determine the phenomenon that occurs. Based on the determination result, the control unit 110 determines whether or not the intermediate transfer unit 41a, the developing unit 41b, the developer, the secondary transfer unit 41c, the drum unit 41d, and the fixing unit 41e are replacement times. As a result, it becomes possible to accurately grasp the unit replacement time. Further, since an appropriate replacement time for the unit can be determined based on the image, the replacement time can be efficiently grasped, and the cost for determining the replacement time can be reduced.

  According to the first to third embodiments, the image reading unit 20 reads an image and obtains original image data. The image forming unit 41 forms an image on a sheet based on the original image data obtained by the image reading unit 20. The control unit 110 compares the original image data obtained by the image reading unit 20 with the read image data, and determines a phenomenon occurring in the image formed on the sheet. As a result, it is possible to easily grasp the unit replacement time.

  Further, according to the first to third embodiments, the image forming unit 41 forms an image on a sheet based on image data included in a print job input from the outside. The control unit 110 compares the original image data, which is image data included in the print job, with the read image data, and determines a phenomenon occurring in the image formed on the paper. As a result, it is possible to easily grasp the unit replacement time.

  Further, according to the first to third embodiments, the image capturing unit 60 reads an image by capturing an image formed on a sheet. As a result, it becomes possible to accurately grasp the unit replacement time.

  Further, according to the first to third embodiments, the control unit 110 causes the operation display unit 30 to display that the unit is in the replacement time when it is determined that the unit is in the replacement time. As a result, the user can easily recognize that it is time to replace the unit.

  Further, according to the second embodiment, when the unit that is not determined to be the replacement time is removed, the control unit 110 notifies the notification unit 70 that the unit is not the replacement time. As a result, it is possible for the user to recognize that the unit that has not been replaced has been removed, and thus it is possible to prevent the unit that has not been replaced from being replaced by mistake.

  Further, according to the third embodiment, the unit lock part 71 locks the attachment / detachment of the unit. The control unit 110 releases the unit lock by the unit lock unit 71 when it is determined that the unit is at the replacement time. As a result, it is possible to prevent a unit that has not been accidentally replaced from being removed.

  Further, according to the first to third embodiments, the second image capturing unit 61 (reading unit 62) is located on the transport unit 420 at a position different from the image capturing unit 60 on the transport unit 420. Read the image of the paper being transported. The control unit 110 includes first read image data obtained by reading an image by the image pickup unit 60, and second read image data obtained by reading an image by the second image pickup unit 61 (reading unit 62). Are compared to determine the phenomenon occurring in the image formed on the paper. As a result, it becomes possible to grasp the replacement time of the unit more accurately.

  The description in the embodiment of the present invention is an example of the image forming apparatus according to the present invention, and the present invention is not limited to this. The detailed configuration and detailed operation of each functional unit constituting the image forming apparatus can be appropriately changed.

  In this embodiment, a score is assigned to each phenomenon, and an evaluation value is obtained based on the score. When the evaluation value exceeds a replaceable threshold, it is determined that the unit is in the replacement period. When this phenomenon occurs, it may be determined that the unit is at the replacement time regardless of the evaluation value.

  In the present embodiment, an image is formed on a sheet based on image data of an image read by the image reading unit 20 or image data included in a print job transmitted from the external device 2, and the image is converted into an image. Although the unit replacement time is determined based on the image read and read by the imaging unit 60, a predetermined test pattern is formed on a sheet, and the test pattern is read by the image imaging unit 60 and read. The unit replacement time may be determined based on the pattern.

  In the first embodiment, a notification unit may be provided, or a unit lock unit may be provided.

  In the present embodiment, an example in which a hard disk, a semiconductor nonvolatile memory, or the like is used as a computer-readable medium for the program according to the present invention is disclosed, but the present invention is not limited to this example. As another computer-readable medium, a portable recording medium such as a CD-ROM can be applied. A carrier wave is also used as a medium for providing program data according to the present invention via a communication line.

DESCRIPTION OF SYMBOLS 1 Image forming apparatus 20 Image reading part 30 Operation display part 41 Image forming part 41a Intermediate transfer unit 41b Developing unit 41c Secondary transfer unit 41d Drum unit 41e Fixing unit 60 Image pick-up part (reading part)
61 Second image capturing unit (second reading unit)
62 Reading unit (second reading unit)
70 Notification part 71 Unit lock part 110 Control part

Claims (8)

An image forming unit for forming an image on paper;
A detachable unit having functions relating to image formation;
A reading unit that is provided on a conveyance unit to which a sheet on which an image is formed by the image forming unit is conveyed, and that reads an image of the sheet conveyed on the conveyance unit;
A phenomenon that occurs in an image formed on the sheet by comparing read image data obtained by reading an image with the reading unit and original image data that is an original of an image formed by the image forming unit. A control unit that determines whether or not the unit is at a replacement time based on the determination result;
An image forming apparatus comprising: An image reading unit that reads the image and obtains the original image data;
The image forming unit forms an image on a sheet based on the original image data obtained by the image reading unit;
The control unit compares the original image data obtained by the image reading unit with the read image data to determine a phenomenon occurring in an image formed on the paper. The image forming apparatus described in 1. The image forming unit forms an image on a sheet based on image data included in a print job input from the outside,
The control unit compares the original image data, which is image data included in the print job, with the read image data, and determines a phenomenon occurring in the image formed on the paper. Item 2. The image forming apparatus according to Item 1.   The image forming apparatus according to claim 1, wherein the reading unit reads an image by capturing an image formed on the sheet. A display unit for displaying predetermined information;
The said control part displays on the said display part that this unit is a replacement time, when it determines with the said unit being a replacement time, The display part as described in any one of Claims 1-4 characterized by the above-mentioned. Image forming apparatus. An informing unit for informing predetermined information;
The said control part makes the said alerting | reporting part notify that the said unit is not replacement time when the unit which is not determined to be replacement time is removed. The image forming apparatus described in the item. A unit lock for locking the attachment and detachment of the unit;
6. The image formation according to claim 1, wherein the control unit releases the lock of the unit by the unit lock unit when it is determined that the unit is in a replacement period. apparatus. The reading unit is a first reading unit,
A second reading unit that reads an image of a sheet conveyed on the conveyance unit at a position different from the first reading unit on the conveyance unit;
The control unit compares the first read image data obtained by reading the image with the first reading unit and the second read image data obtained by reading the image with the second reading unit, thereby comparing the paper. The image forming apparatus according to claim 1, wherein a phenomenon occurring in the image formed on the image is determined.

Images