JP2010175831A - Image forming apparatus, lifetime determination method, and lifetime determination control program - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To more precisely determine the lifetime of a cleaning unit, based on the pixel density of each block. <P>SOLUTION: The image forming apparatus forms an image, by forming an electrostatic latent image on a charged image carrier, developing the electrostatic latent image and transferring a toner image to paper, and prepares for next image formation by cleaning untransferred toner by the cleaning unit; and the image forming apparatus specifies the pixel-existing spot in a writable area to a small area of prescribed unit during image forming operation, to calculate the pixel density in the small area (S3 to S5), subjects the pixel density of each area to weighting (S6) on the basis of the calculated write-in pixel density in the small area, and integrates the pixel density subjected to weighting (S7), and compares the integrated value with a lifetime threshold to determine the lifetime of the cleaning unit (S8, S9 and S10). <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a copying machine, a printer, a facsimile, and an image forming apparatus such as a digital multifunction machine having these functions combined, a method for determining the life of image forming means of the image forming apparatus, and the life determination control by a computer. The present invention relates to a life determination control program for execution.

  As this type of technology, for example, an invention described in Patent Document 1 (Japanese Patent Laid-Open No. 2006-126753) is known. The present invention realizes effective removal of foreign matters such as toner, paper dust, trace additives, charged products and the like adhering to the surface of the photoreceptor at a low cost with a simple structure and an image capable of extending the life of the photoreceptor. In order to provide a forming apparatus, an image area detection means for detecting an image area ratio for each block in a main scanning direction set in advance by numerically processing an input image signal is provided. Based on the image area detection result for each block, control means is provided for controlling the predetermined amount of toner to adhere to the surface of the photoreceptor for each block.

  However, in the invention described in Patent Document 1, the toner adhesion amount is controlled based on the image area detection result for each block, but it is not used for life detection. This is a vacancy that the invention described in Patent Document 1 aims at removing foreign matter, and the life is extended if foreign matter can be removed.

  On the other hand, in the life determination, the life of the photosensitive drum and the life of the developer are generally problems. However, when the foreign matter is removed as described above, the life of the photosensitive drum is extended, but the life of the cleaning unit for collecting the foreign matter is shortened. As the amount of collected foreign matter increases, the amount of time decreases accordingly, and this time the replacement timing of the cleaning unit becomes a problem.

  Therefore, the problem to be solved by the present invention is to make it possible to more accurately determine the lifetime of the cleaning unit based on the pixel density for each block.

  In order to solve the above problems, the first means forms an electrostatic latent image on a charged image carrier, develops the electrostatic latent image, transfers the toner image onto a sheet, and forms an image. An image forming apparatus having an image forming unit that cleans untransferred toner by a cleaning unit and prepares for the next image formation, wherein the pixel location in the writable region is changed to a small unit of a predetermined unit during the image forming operation. Means for specifying, means for calculating the pixel density of the specified small area, and means for determining the lifetime of the cleaning means based on the calculated writing pixel density in each small area. Features.

  The second means is the first means, wherein the specifying means specifies a small region obtained by dividing the pixel location in a matrix in the sub-scanning direction and the main scanning direction, and the determining means is the matrix. Each of the small areas divided into a shape has a storage area, the writing pixel density calculated by the calculating means is integrated in the storage area, and the lifetime is determined based on the integration result. .

  The third means is characterized in that, in the first or second means, the cleaning means is a cleaning unit for the photosensitive member.

  A fourth means is characterized in that, in the first or second means, the cleaning means is a cleaning unit for an intermediate transfer member.

  The fifth means is any one of the first to fourth means, wherein the determining means determines one of paper type information, linear velocity information, resolution, and paper size when determining the life of the cleaning means. The pixel density of the small area is determined by weighting according to the above.

  A sixth means is any one of the first to fifth means, wherein the judging means judges according to a monochrome mode and a color mode.

  The seventh means forms an electrostatic latent image on a charged image carrier, develops the electrostatic latent image, transfers the toner image onto a sheet to form an image, and cleans untransferred toner. A lifetime determination method for determining the lifetime of the cleaning unit of an image forming apparatus having an image forming unit that is cleaned by a unit and preparing for the next image formation, wherein a pixel location in a writable area is predetermined during an image forming operation. Specifying a small area of a unit, calculating a pixel density of the specified small area, and determining a lifetime of the cleaning unit based on the calculated writing pixel density in each small area. And

  The eighth means forms an electrostatic latent image on the charged image carrier, develops the electrostatic latent image, transfers the toner image to a sheet to form an image, and cleans untransferred toner. A life-determination control program for executing life-determination control by a computer to determine the lifetime of the cleaning unit of an image forming apparatus having an image forming unit that is cleaned by a unit and is ready for the next image formation. In accordance with the procedure for specifying the pixel location in the writable area as a small area of a predetermined unit, the procedure for calculating the pixel density of the specified small area, and the calculated write pixel density in each small area And a procedure for determining the life of the cleaning means.

  In the embodiment described later, the image carrier is the photosensitive member 21 and the photosensitive belt 201, and the image forming unit is the sequence device group 13 (the photosensitive member 21, the charging charger 22, the developing unit 23, the transfer charger 24, and the cleaning unit 25). , Fixing unit 20, photosensitive belt 201, charging charger 204, developing units 206a, 206b, 206c, 206d, cleaning unit 215, bias roller 213, intermediate transfer belt 210, transfer roller 214, cleaning unit 216, fixing device 280, etc. ), The means for specifying the small area corresponds to the writing ASIC 12a of the writing unit 12, the means for calculating the pixel density and the means for determining the lifetime correspond to the engine CPU 7, and the storage area corresponds to the EEPROM.

  According to the present invention, the location of pixels in the writable area during the image forming operation is specified as a small area of a predetermined unit, the pixel density of the specified small area is calculated, and the write pixel in each calculated small area Since the lifetime of the cleaning unit is determined based on the integration result of the density or pixel density, the lifetime of the cleaning unit can be accurately determined.

1 is a diagram schematically illustrating a basic configuration of a laser printer according to an embodiment of the present invention. It is the figure which showed schematically the internal mechanical structure of the laser printer of FIG. FIG. 3 is an enlarged view of a fixing device (fixing unit) 30 in FIG. 2 showing details. FIG. 2 is a block diagram schematically showing a printer controller in FIG. 1. It is a figure which shows roughly the method of dividing a writing area | region and counting a pixel. It is a figure which shows schematic structure of the color printer of the indirect transfer system which concerns on other embodiment of this invention. It is a figure which shows the detail of the cleaning unit which cleans the photoreceptor belt of the color printer of FIG. It is a figure which shows the detail of the cleaning unit which performs belt cleaning of the intermediate transfer belt of the color printer of FIG. It is a flowchart which shows the control procedure of the lifetime determination of the cleaning unit in embodiment of this invention.

  The present invention is intended to more accurately determine the life of the cleaning unit. Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  FIG. 1 is a diagram schematically showing a basic configuration of a laser printer according to an embodiment of the present invention. The laser printer 1 includes a controller 2 that performs image processing, an engine 3 that performs image formation, an engine board 4 that controls the engine, and an operation panel 5. The input / output interface 6 of the engine board 4 transmits and receives data among the host computer 15, the controller 2, the operation panel 5, the engine board 4, and the engine 3.

  The CPU 7 controls the entire engine by a program in a memory (ROM) 9 in which an engine control program is stored, a mode instruction from the operation panel 5, and a command from the controller 2. The CPU 7 performs control using the RAM 8 and the EEPROM 10. A RAM 8 is a work memory of the CPU 7 and an input buffer for input data, and an EEPROM 10 is a non-volatile memory for storing an error history of the engine 3, a mode instruction content from the operation panel 5, an integrated value of pixel density which will be described later. is there. In addition, the input / output interface includes a DIP-SW 11 for setting the control mode of the engine 3, a laser writing unit 12 including an LD, a polygon motor, and the like, a sequence device group that manages an engine sequence of a fixing system, a developing system, and a driving system ( Image forming means) 13 and sensors 14 for checking the paper path and sequence state are connected, and data can be transmitted to and received from the controller 2 or the engine CPU 7 as required.

  As shown in FIG. 2, the writing unit 12 deflects laser light modulated in accordance with image data by a polygon mirror and performs optical writing on the photosensitive member 21. In this embodiment, the writing unit 12 includes a pixel in the control circuit of the writing unit 12. Pixel number measuring means for counting the number is set. The number of pixels to be written is extracted from the write image data sent via the controller 2 from a scanner or PC. At that time, as shown in FIG. 5 to be described later, the main scanning direction and the sub-scanning direction are divided into predetermined areas, and for each divided area, the number of pixels included in the area is counted by a counter and stored in the memory. Remember. The control of dividing the number of pixels into regions and counting is executed by the CPU of the control circuit of the writing unit 12.

  FIG. 2 is a diagram schematically showing the internal mechanism of the laser printer 1 according to the present embodiment. Reference numeral 20 in the figure denotes the apparatus main body. Inside the apparatus main body 20, a belt-like photoconductor 21 is provided substantially at the center, and a charging charger 22, a developing unit 23, and a transfer charger are sequentially arranged along the outer periphery of the photoconductor 21 in the driving direction indicated by the arrows in the drawing. 24, a cleaning unit 25 is provided. An optical writing unit 12 having a pixel number measuring unit is disposed on the upper side of the developing unit 23, and a sheet feeding cassette 27 containing sheets is detachably attached to the lower side of the apparatus main body 20 in the drawing. In addition, a sheet conveying system for paper supply / discharge is provided. A fixing unit 30 is provided at the final stage of the sheet conveying system, and fixes the image formed on the sheet.

  In the above configuration, when an image is formed, a motor (not shown) is driven to rotate the paper feed roller 28, and the sheet is sent out from the paper feed cassette 27 in the direction of the arrow in the drawing, and the image is held by the registration roller pair 29 at the timing. It is transported to the lower side of the photoconductor 21 as a body. The photoreceptor 21 rotates in the clockwise direction indicated by the arrow. At this time, the surface is uniformly charged by the charging charger 22, and thereafter, the laser beam emitted from the optical writing unit 26 is irradiated to form an electrostatic latent image on the photosensitive member 21. The latent image is visualized by toner when passing through the position of the developing unit 23, and the visible image is transferred by the transfer charger 24 onto the upper surface of the sheet conveyed to the lower side of the photoreceptor 21.

  The sheet after the image transfer is conveyed to the fixing unit 30 and the transferred image is fixed on the sheet. The sheet exiting the fixing unit 30 is transported into the face-down transport path 31 by the FD / FU switching solenoid claw 34, and face-down discharged in a face-down state with the recording surface down by the face-down discharge roller pair 32. The sheet is discharged onto the tray 33 or is directly discharged onto the face-up discharge tray 35 with the recording surface facing up. On the other hand, the residual toner is removed from the photoreceptor 21 after the image transfer by the cleaning unit 25, and then the charge is removed by a charge removal unit (not shown).

  FIG. 3 is an enlarged view showing details of the fixing device (fixing unit) 30 of FIG. As shown in FIG. 2, the fixing unit 30 includes upper and lower fixing rollers 45 and 46 with built-in heat source lamps 43 and 44. The thermistor 58 for detecting the surface temperature of the fixing roller 45 is in contact with the fixing roller 45 to obtain temperature information for controlling the surface temperature of the fixing rollers 45 and 46 to a necessary fixing temperature. Further, the fixing unit 30 is equipped with a memory 49 for storing information unique to the fixing unit 30.

  The memory 49 is a non-volatile memory that is backed up by an EEPROM or a battery, and is further readable and writable. When the fixing unit 30 is mounted on the apparatus main body 20, the memory 49 is used for operation control mounted on the apparatus main body 20. It is connected to the engine CPU 7 (FIG. 1). As a result, information unique to the fixing unit 30 stored in the memory 49 can be read by the engine CPU 7 on the apparatus main body 20 side, and control corresponding to this can be performed, and information can be stored in the memory 49 from the engine CPU 7 side. This can be used as needed. For example, the main body CPU 7 can determine whether or not the usage frequency of the fixing unit 30 stored in the memory 49 has reached a value corresponding to the life of the fixing unit 30, and can perform processing corresponding thereto. The operation relating to the lifetime is the same for the photosensitive member 21.

The memory 49 is mounted on the substrate 81 together with the thermistor 82, and is installed in a heat insulating chamber 85 separated from the fixing rollers 45 and 46 in the fixing unit 30 by a heat insulating wall 83. The influence is excluded. Further, when the ambient temperature of the substrate 81 becomes equal to or higher than a predetermined temperature, this is detected by the thermistor 82 and the cooling fan 84 is driven to guarantee the temperature of the memory 49.
FIG. 4 is a block diagram schematically showing the configuration of the printer controller 2 in the present embodiment. The printer controller 2 includes a CPU 101, an IC card 102, an NVRAM 103, a program ROM 104, a font ROM 105, a RAM 106, and various I / Fs 107, 109, 111, and 113.

  The CPU 101 controls the entire controller 2 by a program stored in the program ROM 104, a mode instruction from the operation panel 5, and a command from the host computer 15. The IC card 102 is a card that can be arbitrarily inserted and removed to supply font data and programs from the outside. The NVRAM 103 is a nonvolatile storage device that stores the contents of mode instructions from the panel device, and the program ROM 104 is a memory that stores a control program for the controller 2. A font ROM 105 stores font pattern data and the like, and a RAM 106 is a writable / readable memory used for a work memory of the CPU 101, an input buffer for input data, a page buffer for print data, a memory for downloaded fonts, and the like.

  The engine I / F 107 is an interface that communicates commands, statuses, and print data with the engine 3, and the engine 3 includes a writing unit 12 and a sequence device group 13 as shown in FIG. 1, and forms an image on a sheet. It has the function to do. The panel I / F 109 is an interface that communicates commands and status with the operation panel 5. The operation panel 5 is used to inform the user (user) of the current printer status and to give a mode instruction. The host I / F 111 is an interface that communicates with the host computer 15, and is typically a Centro I / F or RS232C. The disk I / F 113 is an interface for communicating with the disk device 114, and the disk device 114 is a storage device for storing various data such as font data, programs, print data, and the like, such as a floppy disk device or a hard disk. The device is used.

  FIG. 5 is a diagram for explaining a pixel counting method. The pixel count is performed by the pixel number coefficient means set in the control circuit (write ASIC) 12a of the writing unit 12. That is, a pixel number counting unit is realized as a function of the writing ASIC 12a. That is, the writing ASIC 12a has a function of forming a matrix in the sub-scanning direction (Y direction) and the main scanning direction (X direction), and specifying the location of the pixel in the lattice constituted by the matrix. A writable area (in the figure, the main scanning direction is X1-XM (M is an integer from 1 to 16 in the present embodiment), and the sub-scanning direction Y1-YN (N is a positive integer of 1 or more). ) Is divided into small areas by a lattice, and pixel information contained in the small areas is integrated for each small area R11, R12,..., R21, R22,. Get the accumulated information. At this time, if the number of scanning lines reaches N (LINE) (YN), the number of pixels is determined, and the determination is notified to the engine CPU 7 by interruption. The scanning line N can be set to a predetermined register from the outside and is variable.

  FIG. 6 is a diagram showing a schematic configuration of an indirect transfer type color printer. This type of color printer uses an intermediate transfer belt in addition to the photosensitive belt. In FIG. 6, a color printer 200 includes a photosensitive belt 201 carrying an electrostatic latent image formed by laser writing and a developed toner image, and a charging charger 204 for uniformly charging the surface of the photosensitive belt 201. A laser writing unit 205, color developing devices 206a, 206b, 206c, and 206d, an intermediate transfer belt 210 that forms an image on the photosensitive belt 201 on a transfer sheet via an intermediate transfer member, and an intermediate transfer belt 210. The image forming apparatus includes a transfer roller 214 that transfers the image, a fixing device 280, a pair of paper discharge rollers 281a and 281b, and a paper discharge stack unit 282.

  In this apparatus, the photosensitive member carrying the electrostatic latent image formed by laser writing and the developed toner image is a photosensitive belt 201 as a flexible belt-like image carrier. The photosensitive belt 201 is installed between the rotating rollers 202, 231, and 232, and is rotated (sub-scanned) in the direction of arrow A (clockwise) in the drawing by the rotational driving of the rotating roller 202, and the belt surface is imaged. It forms so that it may become a formation surface. As means for forming an electrostatic latent image and a toner image on the photosensitive belt 201, a charging charger 204 for uniformly charging the surface of the photosensitive belt 201, a laser writing unit 205, color developing devices 206a and 206b, 206c, 206d. The color developing devices 206a, 206b, 206c, and 206d include developing units for magenta, cyan, yellow, and black, which are color constituent colors. The developing unit used here performs development with a one-component developer (toner).

  In this embodiment, since the image on the photosensitive belt 201 is formed on the transfer paper via the intermediate transfer member, the intermediate transfer belt 210 is provided. The intermediate transfer belt 210 is installed between the rotation rollers 211 and 212, and rotates in the arrow B direction (counterclockwise direction) in the drawing by the rotation driving of the rotation roller 211. The photosensitive belt 201 and the intermediate transfer belt 210 are in contact with each other at a portion where the rotating roller 232 of the photosensitive belt 201 is provided. On the intermediate transfer belt 210 side of the contact portion, a conductive bias roller 213 is in contact with the back surface of the intermediate transfer belt 210 under a predetermined condition.

  Further, as components relating to the processing of the transfer paper, a paper feed unit (paper feed cassette) 217, paper feed rollers 218, transport roller pairs 219a and 219b, registration roller pairs 220a and 220b, and an intermediate transfer belt are provided. The image forming apparatus includes a transfer roller 214 that transfers an image from 210, a fixing device 280, a pair of paper discharge rollers 281a and 281b, and a paper discharge stack unit 282.

  In the color printer 200 configured as described above, the photosensitive belt 201 as a flexible belt-shaped image carrier is uniformly charged by the charging charger 204, and then based on the image information by the laser writing unit 205. In this way, an electrostatic latent image is formed on the surface by scanning exposure of a laser whose emission is controlled. Image information used in one step of forming an electrostatic latent image by scanning exposure while rotating the photosensitive belt 201 is monochromatic image information obtained by separating a desired full-color image into magenta, cyan, yellow, and black color information. Based on this information, the emission of the semiconductor laser is controlled. The generated laser beam is scanned and optical path adjusted by an optical device, and output as writing beam light L. The electrostatic latent image formed based on the single color image information is converted into magenta (M), cyan (C), yellow (Y), and black (Bk) toners by the color developing devices 206a, 206b, 206c, and 206d. Each color image is developed, and each color image is sequentially formed on the photosensitive belt 1. Each monochrome image of M, C, Y, and Bk formed on the photosensitive belt 201 rotating in the direction of arrow A in FIG. 6 rotates in the direction of arrow B in FIG. 6 in synchronization with the photosensitive belt 201. On the intermediate transfer belt 210, the images are successively transferred in an overlapping manner by the action of a predetermined transfer bias applied to the bias roller 213. The M, C, Y, and Bk images superimposed on the intermediate transfer belt 210 are fed from a paper feed table (paper feed cassette) 217 through a paper feed roller 218, a pair of conveyance rollers 219a and 219b, and a pair of registration rollers 220a and 220b. Then, the transfer roller 214 performs batch transfer onto the transfer paper 217a conveyed to the transfer unit. After the transfer is completed, the transfer sheet 217a is fixed by the fixing device 280, and is discharged as a full-color print image to the discharge stack unit 82 through the discharge roller pair 281a and 281b.

  In addition, it is necessary to clean the toner on the photosensitive belt 201 as the final step of image formation on the photosensitive belt 201. For this purpose, a cleaning unit 215 including a cleaning blade that is always in contact with the photosensitive belt 201 is provided. Similarly, the intermediate transfer belt 210 is also provided with a cleaning unit 216. The cleaning brush 251 of the cleaning unit 216 is held at a position separated from the surface of the intermediate transfer belt 210 during the image forming operation, and contacts the surface of the intermediate transfer belt 210 after the formed image is transferred onto the transfer paper 217a. Alternatively, the photosensitive belt 201, the charging charger 204, the intermediate transfer belt 210, the photosensitive belt cleaning unit 215, and the intermediate transfer belt cleaning unit 216 may be integrated so as to be removable from the main body as a process cartridge.

  FIG. 7 is a diagram showing details of the photosensitive belt cleaning unit 215 for cleaning the photosensitive belt 201 of the color printer 200 shown in FIG. Since the laser printer 1 shown in FIG. 2 is also the same, the cleaning unit CLU1 of the color printer 200 shown in FIG.

  In this figure, a fur brush 241 and a counter blade 242 arranged on the downstream side in the rotation direction of the photosensitive belt 201 of the fur brush 241 are slidably contacted with the photosensitive belt 201, and the fur brush 241 and the counter blade 242 make photosensitivity. Untransferred toner on the body belt 201 is cleaned. A Mars bar 243 is attached to the fur brush 241 so as to be in sliding contact, and zinc stearate is applied to the photoreceptor belt by the fur brush 241 to improve transfer and cleaning properties. Untransferred toner that has been swept by the fur brush 241 and scraped by the counter blade 242 falls to the toner receiving portion 244, and is transported to the toner recovery portion 246 by the transport auger 245 and recovered.

  FIG. 8 is a diagram showing details of the intermediate transfer belt cleaning unit 216 that performs belt cleaning of the intermediate transfer belt 210 of the color printer 200 shown in FIG. In this embodiment, a bias brush roller 251 is disposed opposite to the rotation roller 211, and the untransferred toner on the intermediate transfer belt 210 is adsorbed and removed by the bias brush roller 251, and further slidably contacted with the bias brush roller 251. The untransferred toner attracted to the bias brush roller 251 is collected by the bias roller 252 and the cleaning blade 253 that is in sliding contact with the bias roller 252. Further, a Mars bar 254 is attached to the bias brush roller 251 so as to be in sliding contact, and zinc stearate transferred to the bias brush roller 251 is applied onto the intermediate transfer belt 210 to improve transfer and cleaning properties. The untransferred toner scraped off by the cleaning blade 253 falls to the toner receiving portion 255 and is transported to the toner recovery portion 257 by the transport auger 256 and recovered.

  In this way, the cleaning units 215 and 216 collect the untransferred toner. However, if a portion where a lot of toner is attached is collected, the portion deteriorates faster than a portion where the toner is not attached, and the life is shortened. Therefore, it is necessary to determine the lifetime and replace the cleaning units 215 and 216 before the lifetime is exceeded. In this case, it is economically desirable to replace the battery immediately before the end of its life.

  FIG. 9 is a flowchart showing the control procedure of this life determination. In the figure, when a print request is received from the host computer 15 (step S1), image data is sent to the engine 3 via the printer controller 2 (step S2), and the engine 3 responds to the image data sent from the controller 2. Then, image processing is performed (step S3), the photosensitive unit 21 is irradiated with laser light from the writing unit 12 to form a latent image, and an image is created on the sheet by the sequence device group 13. Here, the pixel number counting means of the writing unit 12 specifies the pixels at the fixing side end of the small area divided as described above and counts the number of pixels (step S4).

  Next, the pixel density is calculated from the counted number of pixels (step S5), and depending on the paper type, linear velocity, resolution, printing surface, paper size, color mode (monochrome mode or color mode (full color mode)) The weighting is performed on the pixel density of the small area (step S6), the weighted pixel density is accumulated for each small area every time image formation is performed, and the accumulated value is stored in the EEPROM 10 for each small area. Store in the area (step S7). Then, the integrated value for each small area stored in the storage area is compared with a preset threshold value indicating a lifetime (step S8), and when the integrated value exceeds the threshold value (step S204-Y), the lifetime is reached. It is determined that it has reached (step S9), and it is determined that the lifetime has not yet been reached (step S10). When the service life is reached, for example, a message to that effect is displayed on the operation panel 5 to prompt replacement.

  Note that the weighting is performed, for example, by weighting the outermost pixel of the small area divided in a grid shape with the heaviest weight and decreasing the weight in the middle. In addition, specific weighting values are experimentally accumulated for each element together with the time element, and set based on the accumulated data.

  In this way, by dividing into small areas, specifying which area the writing position is, and adding up the pixel density for each image formation, which part of the unit was used more often It can be determined whether the usage amount of a certain part has reached the end of its life. This makes it possible to accurately determine the life of the unit.

As described above, according to the present embodiment,
1) Since the lifetime is determined based on the integrated value of the writing pixel density corresponding to the writing position, not the number of sheets to be passed, the lifetime can be determined more accurately.
2) Since the lifetime is determined for the cleaning units 25, 215, and 216, the lifetime of the cleaning units 25, 215, and 216 of the image forming apparatus can be accurately determined.
At that time, weighting is performed according to the paper type information, taking into consideration the variation factors of the life determination due to the difference in the paper type, and weighting according to the linear speed information, and fluctuations in the life determination due to the difference in the linear speed By adding factors, weighting is performed according to the resolution, and by adding a variable for determining the life due to the difference in resolution, weighting is performed according to the paper size, and the variable due to differences in the paper size In consideration of the above, it is possible to perform a more suitable life determination and maintain good fixing quality.
3) When performing the life determination, the state of the untransferred toner differs between the monochrome mode and the color mode depending on the difference in toner characteristics or the state of the superimposed toner. Therefore, the determination is made in consideration of the difference between these color modes. As a result, a more suitable lifespan determination can be performed, and good fixing quality can be maintained.
4) The writing ASIC 12a is divided into a matrix form in the sub-scanning direction and the main scanning direction, and a function that can specify the divided small areas is provided, and the pixel information of the small areas is integrated. Accumulated information on the correct writing position can be acquired.
5) Accumulated information on the writing position can be acquired more accurately, so that a more accurate lifespan can be determined.
There are effects such as.

  In addition, this invention is not limited to this embodiment, All the technical matters contained in the technical thought described in the claim are object.

  The present invention can be used to determine the life of an entire cleaning unit of an image forming apparatus that forms an image by transferring toner, regardless of a direct transfer method or an indirect transfer method.

DESCRIPTION OF SYMBOLS 1 Laser printer 2 Controller 3 Engine 4 Engine board 5 Operation panel 6 Input / output interface 7 (Engine) CPU
10 EEPROM
12 writing unit 12a writing ASIC
13 sequence device group 20 apparatus main body 21 photoconductor 201 photoconductor belt 210 intermediate transfer belt 25, 215, 216 cleaning unit

JP 2006-126753 A

Claims (8)

An electrostatic latent image is formed on the charged image carrier, the electrostatic latent image is developed, the toner image is transferred to a sheet to form an image, and untransferred toner is cleaned by a cleaning means next time. An image forming apparatus having image forming means for image formation of
Means for specifying a pixel-existing location in a writable area in a predetermined unit during an image forming operation;
Means for calculating a pixel density of the specified small region;
Means for determining the lifetime of the cleaning means based on the calculated writing pixel density in each small region;
An image forming apparatus comprising: The image forming apparatus according to claim 1,
The specifying means specifies a small area obtained by dividing the pixel location in a matrix in the sub-scanning direction and the main scanning direction,
The determination means has a storage area for each small area divided into the matrix, integrates the write pixel density calculated by the calculation means in the storage area, and based on the integration result, the lifetime Determining an image. The image forming apparatus according to claim 1, wherein:
An image forming apparatus, wherein the cleaning unit is a cleaning unit for a photoconductor. The image forming apparatus according to claim 1, wherein:
An image forming apparatus, wherein the cleaning unit is a cleaning unit for an intermediate transfer member. The image forming apparatus according to any one of claims 1 to 4, wherein
The determining means weights the pixel density of the small area according to any of paper type information, linear velocity information, resolution, and paper size when determining the life of the cleaning means. A featured image forming apparatus. An image forming apparatus according to any one of claims 1 to 5,
The image forming apparatus according to claim 1, wherein the determining unit determines according to a monochrome mode and a color mode. An electrostatic latent image is formed on the charged image carrier, the electrostatic latent image is developed, the toner image is transferred to a sheet to form an image, and untransferred toner is cleaned by a cleaning means next time. A lifetime determination method for determining the lifetime of the cleaning unit of an image forming apparatus having an image forming unit for image formation,
Specify the pixel location in the writable area during the image forming operation as a small area of a predetermined unit, calculate the pixel density of the specified small area,
A service life determination method comprising: determining the service life of the cleaning unit based on the calculated writing pixel density in each small region. An electrostatic latent image is formed on the charged image carrier, the electrostatic latent image is developed, the toner image is transferred to a sheet to form an image, and untransferred toner is cleaned by a cleaning means next time. A life determination control program for executing life determination control for determining the life of the cleaning unit of an image forming apparatus having an image forming unit for image formation by a computer,
A procedure for specifying the pixel location in the writable area during the image forming operation as a small area of a predetermined unit;
Calculating the pixel density of the identified small region;
A procedure for determining the lifetime of the cleaning means based on the calculated writing pixel density in each small region;
A life determination control program characterized by comprising:

Images