JP2015069184A - Image forming apparatus, image forming apparatus control method and program - Google Patents

Abstract

PROBLEM TO BE SOLVED: To accurately calculate the consumption amount of a printing agent such as toner, and to enable display of a remaining amount with a small deviation (error) between the detected remaining amount of the printing agent and the physical remaining amount. SOLUTION: A controller 302 performs run-length compression for each page in print data in line or block units, obtains a black pixel occupancy rate from a composition ratio of black pixels and white pixels (S104), and uses toner. Using the amount calculation table, the toner consumption corresponding to the occupancy rate and the paper size used for printing is obtained (S105), and the correction value corresponding to the degree of scattering of the black pixels is obtained by using the toner usage correction table. Obtained by reference, and the correction value is used to correct the toner consumption (S104, S105). [Selection diagram] FIG. 5

Description

  The present invention relates to an image forming apparatus having a function of detecting the remaining amount of a printing agent such as toner.

  Conventionally, there has been proposed an image forming apparatus that calculates the toner consumption and manages the remaining amount of toner in the apparatus. If the toner amount in the apparatus can be managed accurately, the user can know the remaining amount of toner in the apparatus, and a new cartridge can be prepared at the time of replacement, which is very convenient for the user. is there.

  Japanese Patent Application Laid-Open No. 2004-133867 proposes a technique for calculating a toner consumption amount using a dot counter, and the toner remaining amount can be managed using the toner consumption amount.

JP 2012-194379 A

  With the technique of calculating the toner consumption amount using a dot counter as in Patent Document 1, it is possible to calculate the toner consumption amount with high accuracy. However, the image forming apparatus that does not include a dot counter cannot use the technique of Patent Document 1. Therefore, more accurate remaining amount detection has been studied in an image forming apparatus that does not include a dot counter.

  The present invention has been made to solve the above problems. An object of the present invention is to provide a mechanism that can accurately calculate the amount of consumption of a printing agent such as toner and that can display a remaining amount with little deviation (error) between the detected remaining amount of the printing agent and the physical remaining amount. Is to provide.

  The present invention is an image forming apparatus, which performs run-length compression on a line or block basis for each page in print data, and calculates a black pixel occupancy ratio from the composition ratio of black pixels and white pixels; Using a table, a predicting means for obtaining a toner consumption amount corresponding to the occupation ratio obtained by the calculating means and a paper size used for printing, and a correction value corresponding to the degree of scattering of the black pixels are corrected. It has an acquisition means which acquires with reference to a table, and a correction means which corrects the amount of toner consumption which said prediction means calculated using the correction value which said acquisition means acquired.

  According to the present invention, the consumption amount of a printing agent such as toner can be accurately calculated. As a result, it is possible to display the remaining amount with a small difference (error) between the detected remaining amount of the printing agent and the physical remaining amount.

1 is a diagram illustrating a system configuration of an image forming apparatus according to an embodiment of the present invention. The figure which illustrates the structure of a controller. 2 is a diagram illustrating a configuration of a printer engine. FIG. 6 is a flowchart illustrating a process related to the remaining amount of toner according to the exemplary embodiment. 6 is a flowchart illustrating toner consumption calculation processing. 9 is a flowchart illustrating toner usage amount correction processing. The figure which illustrates a toner usage-amount calculation table. FIG. 6 is a diagram illustrating a toner usage correction table. The figure which illustrates a toner usage-amount correction value setting screen.

  Hereinafter, embodiments for carrying out the present invention will be described with reference to the drawings.

[Description of printer system configuration]
FIG. 1 is a diagram illustrating an example of a schematic system configuration of an image forming apparatus according to an embodiment of the present invention.
In FIG. 1, a data processing apparatus 101 is a computer, for example, and functions as a supply source of image information. The image forming apparatus 102 is, for example, an electrophotographic printer, and may have a scanner function or a FAX function. The image forming apparatus 102 includes a printer controller (hereinafter referred to as a controller) 302, a panel unit 301, a printer engine 303, and the like.

  The controller 302 generates raster data for each page based on image information (for example, page description language (hereinafter referred to as PDL)) supplied from the data processing apparatus 101 and sends the raster data to the printer engine 303. The panel unit 301 is used as a user interface. The controller 302 receives a desired operation instruction from the user via the panel unit 301. Further, the controller 302 notifies the user of the state of the image forming apparatus 102, a warning to the user, and the like via the panel unit 301. The state of the image forming apparatus 102 displayed on the panel unit 301 includes the remaining amount of toner acquired via the toner cartridge control unit 509. The printer engine 303 forms a latent image on the photosensitive drum based on the raster data supplied from the controller 302, and transfers the toner onto the recording medium and fixes the image on the recording medium (electrophotographic method). Record.

[Description of controller system configuration]
FIG. 2 is a block diagram illustrating an example of the configuration of the controller 302.
In FIG. 2, 401 is a panel I / F unit for performing data communication with the panel unit 301. The CPU 407 receives settings and instruction contents from the user via the panel unit 301 via the panel I / F unit 401.

  A host I / F unit 402 is for two-way communication connection with a data processing apparatus 101 such as a host computer via a network. A ROM 403 holds processing described in the present invention and other control program codes executed by the image forming apparatus 102. Reference numeral 404 denotes a RAM. The RAM 404 stores print data received via the host I / F unit 402, intermediate data generated by interpreting the print data, bitmaps generated by rendering the intermediate data, and temporary processing necessary for other processing. Various processing statuses and log information are stored. In addition, the program code executed by the CPU 407 is read from the ROM 403 or the like and expanded in the RAM 404.

  Reference numeral 405 denotes an engine I / F unit for communication connection with the printer engine 303. The CPU 407 recognizes the state of the printer engine 303 via the engine I / F unit 405. Reference numeral 406 denotes a DMA control unit. The CPU 407 transfers the bitmap data stored in the RAM 404 to the engine I / F unit 405 via the DMA control unit 406.

  A CPU 407 controls devices connected to the CPU bus 420 based on control program codes stored in the ROM 403. Reference numeral 408 denotes an EEPROM which is a non-volatile memory for holding setting information of the image forming apparatus 102. The EEPROM 408 is also a part that holds information of a toner usage amount calculation table 601 in FIG. 7 described later and a toner usage amount correction table 701 in FIG.

  Reference numeral 409 denotes a media I / F unit for reading and writing various data such as image data, program data, and device setting data from a removable medium 304 such as a USB memory.

  Reference numeral 410 denotes one module of a program group held in the ROM 403 called a job control unit. This program is expanded from the ROM 403 to the RAM 404 and executed by the CPU 407. The CPU 407 executes print processing after storing the data received from the data processing apparatus 101 in the RAM 404 as a print job by the execution of the job control unit 410. Further, the CPU 407 stores the data received from the data processing apparatus 101 in the RAM 404 as a print job or deletes the stored print job from the RAM 404 by executing the job control unit 410.

  Reference numeral 411 denotes an intermediate data creation unit that performs processing for converting a print job received from the data processing apparatus 101 via the host I / F unit 402 into intermediate data that is easy to handle inside the image forming apparatus 102. The intermediate data creation unit 411 is a program module stored in the ROM 403. The program is loaded from the ROM 403 to the RAM 404 and then executed by the CPU 407.

  Reference numeral 412 denotes a rendering unit that develops a bitmap image in accordance with the content of the intermediate data stored in the RAM 404 by the intermediate data creation unit 411. Reference numeral 412 denotes a module of a program stored in the ROM 403, which is a rendering unit, and is executed by the CPU 407 after being expanded from the ROM 403 to the RAM 404.

  Reference numeral 413 denotes a module of a program held in the ROM 403, which is a toner remaining amount calculation unit. The program module is expanded from the ROM 403 to the RAM 404 and then executed by the CPU 407.

  Reference numeral 414 denotes a toner usage amount calculation unit that calculates a toner usage amount by obtaining a ratio of the number of effective dots of a page to be printed. The toner usage calculation unit 414 is a program module stored in the ROM 403. The program is developed from the ROM 403 to the RAM 404 and then executed by the CPU 407. The CPU 407 calculates the toner remaining amount by executing the toner remaining amount calculating unit 413. The CPU 407 displays the calculated remaining toner amount as a remaining toner amount on the panel unit 301 via the panel I / F unit 401 or as a remaining toner amount on the data processing apparatus 101 via the host I / F unit 402. Or notify.

  A CPU bus 420 includes an address, data, and control bus. Each of the devices 401 to 409 can access all the devices connected to the CPU bus 420.

[Description of printer engine system configuration]
FIG. 3 is a block diagram illustrating an example of the configuration of the printer engine 303.
As shown in FIG. 3, the printer engine 303 includes at least devices 501 to 506 and a control unit.

  Reference numeral 502 denotes a ROM that holds control program codes executed by the printer engine 303. Reference numeral 503 denotes a RAM. The RAM 503 stores print data received via the controller I / F unit 507, status information indicating the state of the printer engine 303, and the like. In the RAM 503, program codes executed by the CPU 501 are read from the ROM 502 and developed.

  Reference numeral 504 denotes an environment sensor unit for measuring temperature and humidity. A drive control unit 505 drives various motors for performing predetermined image forming processing. Reference numeral 506 denotes an abnormality detection unit that detects an abnormality such as a cover of the image forming apparatus or a paper jam. Reference numeral 507 denotes a controller I / F unit for performing notification with the controller 302 based on a predetermined communication protocol.

  The CPU 501 controls devices connected to the CPU bus 510 based on the control program code stored in the ROM 502 or the like. The CPU 501 notifies the controller 302 of the state information changed by the units 504 to 506 via the controller I / F unit 507. In addition, the CPU 501 receives an instruction command from the controller 302 via the controller I / F unit 507, and transmits the instruction content to a related device.

  An image forming unit 508 performs predetermined image forming processing (for example, charging, exposure, development, transfer, and fixing in the electrophotographic technology) on the bitmap image information transmitted from the controller 302 via the controller I / F unit 507. A series of processing) is performed. A toner cartridge control unit 509 performs various controls on the toner cartridge mounted on the printer engine 303. A CPU bus 510 includes an address bus, a data bus, and a control bus. Each device can access all devices connected to the CPU bus 510.

  Hereinafter, processing of the image forming apparatus of the present invention will be described with reference to the flowcharts of FIGS. 4 to 6 is realized by the CPU 407 of the controller 302 executing a program stored in the ROM 403 or the like. 4 is realized by the CPU 501 of the printer engine 303 executing a program stored in the ROM 502 or the like.

[Description of Processing of Controller 302 and Printer Engine 303 Related to Remaining Toner]
FIG. 4 is a flowchart illustrating a processing procedure related to the remaining amount of toner in the controller 302 and the printer engine 303. In FIG. 4, S <b> 11 to S <b> 20 are processes executed by the CPU 407 of the controller 302. The CPU 407 executes communication processing with the printer engine 303 via the engine I / F unit 405. S31 to S35 are processes executed by the CPU 501 of the printer engine 303. Note that the CPU 501 executes communication processing with the controller 302 via the controller I / F unit 507.

  First, in S <b> 11, the CPU 407 of the controller 302 determines whether there is a possibility that the toner cartridge has been replaced via the toner cartridge control unit 509. For example, when there is a possibility that the toner cartridge has been replaced, the toner cartridge control unit 509 notifies the controller 302 to that effect. When the CPU 407 receives a notification from the toner cartridge control unit 509 that the toner cartridge may be replaced, the CPU 407 determines that the toner cartridge may be replaced. On the other hand, if the notification has not been received, the CPU 407 determines that there is no possibility that the toner cartridge has been replaced.

  If it is determined in S11 that there is no possibility that the toner cartridge has been replaced (No in S11), the CPU 407 repeats the determination in S11. On the other hand, if it is determined in S11 that the toner cartridge may be replaced (Yes in S11), the CPU 407 advances the process to S12.

  In step S <b> 12, the CPU 407 transmits a toner cartridge information acquisition command to the printer engine 303 via the engine I / F unit 405 in order to acquire toner cartridge information attached to the toner cartridge control unit 509.

  In step S <b> 31, the CPU 501 of the printer engine 303 receives the command transmitted from the controller 302 in step S <b> 12 via the controller I / F unit 507. Next, in S <b> 32, the CPU 501 interprets the command received in S <b> 31, and returns toner cartridge information held by the toner cartridge control unit 509 to the controller 302 via the controller I / F unit 507 in accordance with the interpretation. The information returned in S32 is toner cartridge information held by the toner cartridge control unit 509, and includes, for example, the remaining amount of toner processed in S14 and S19 described later. When there is a possibility that the toner cartridge has been replaced, the toner cartridge control unit 509 reads out toner cartridge information including the toner amount of the toner cartridge from a nonvolatile memory provided in the toner cartridge. It is assumed that toner cartridge information such as the amount of toner stored in the toner cartridge at the time of manufacture or the like is stored in the nonvolatile memory of the toner cartridge. Here, the configuration in which the toner cartridge is provided with a non-volatile memory and the amount of toner is stored in the non-volatile memory has been described. However, the present embodiment is not limited to this. For example, the toner cartridge control unit 509 may return toner cartridge information such as the amount of toner determined according to the type of toner cartridge to the controller 302.

In S <b> 13, the CPU 407 of the controller 302 receives the return status from the printer engine 303 in S <b> 32 via the engine I / F unit 405.
Next, in S <b> 14, the CPU 407 sets an initial value of the remaining amount of toner based on the information received from the printer engine 303, and holds it in the remaining toner calculation unit 413. The initial value of the remaining toner amount set here is displayed on the panel unit 301 via the panel I / F unit 401 or displayed on the data processing apparatus 101 via the host I / F unit 402. This is used to notify the remaining amount of toner.

  In step S <b> 15, the CPU 407 determines whether a print instruction has been issued from the data processing apparatus 101 via the host I / F unit 402. If it is determined that the print instruction has not been given (No in S15), the CPU 407 proceeds to S11. On the other hand, if it is determined that a print instruction has been issued (Yes in S15), the CPU 407 proceeds to S16.

  In S <b> 16, the CPU 407 calculates the toner usage amount (consumption amount) of the image image sent and printed from the data processing apparatus 101 via the host I / F unit 402 by the toner usage amount calculation unit 414. Control is performed (details of S16 are shown in FIG. 5 described later).

  In step S <b> 17, the CPU 407 instructs the printer engine 303 to print the image image instructed to print from the data processing apparatus 101 via the host I / F unit 402 via the engine I / F unit 405. Send print start command.

  In step S33, the CPU 501 of the printer engine 303 receives the command transmitted from the controller 302 in step S17 via the controller I / F unit 507. The image forming unit 508 performs a predetermined image forming process on the bitmap image information transmitted from the controller 302 via the controller I / F unit 507. The predetermined image forming process corresponds to a series of processes such as charging, exposure, development, transfer, and fixing in the electrophotographic technology.

  The CPU 501 waits for the image forming process of the image forming unit 508 to end, and returns a print end notification to the controller 302 via the controller I / F unit 507 in S34.

  In S <b> 18, the CPU 407 of the controller 302 receives the return status transmitted from the printer engine 303 in S <b> 34 via the engine I / F unit 405. Thereafter, based on the information received from the printer engine 303, the CPU 407 displays, for example, that printing has been completed on the panel unit 301 via the panel I / F unit 401.

  Next, in S <b> 19, the CPU 407 updates the value of the remaining toner amount held by the remaining toner amount calculation unit 413 based on the toner usage amount obtained by the toner usage amount calculation unit 414 in S <b> 16. Further, the CPU 407 transmits a command for updating the remaining toner amount of the toner cartridge control unit 509 via the engine I / F unit 405.

In step S <b> 35, the CPU 501 of the printer engine 303 receives the command transmitted from the controller 302 in step S <b> 19 via the controller I / F unit 507. Further, the CPU 501 updates the remaining amount of toner held by the toner cartridge control unit 509 with the value included in the received command. Further, the toner cartridge control unit 509 updates the toner amount stored in the nonvolatile memory provided in the toner cartridge, using the updated remaining toner amount. Here, the configuration in which the toner cartridge is provided with a non-volatile memory and the toner amount is stored in the non-volatile memory has been described, but the present embodiment is not limited to this.
When the process of S35 is completed, the CPU 501 repeats the process from S31.

  In S <b> 20, the CPU 407 of the controller 302 displays the remaining toner amount updated in S <b> 19 as the remaining toner amount on the panel unit 301 via the panel I / F unit 401. Thereafter, the CPU 407 repeats the processing from S11.

(Description of processing for calculating toner usage (consumption))
FIG. 5 is a flowchart showing the processing of the toner usage amount calculation unit 414 and showing the detailed procedure of the toner usage amount calculation processing performed in S16 of FIG. Note that the processing of this flowchart is executed by the CPU 407 of the controller 302.

  First, in step S <b> 101, the CPU 407 of the controller 302 derives a toner usage amount calculation table 601 corresponding to the own apparatus in FIG. 7 from the engine type of the printer engine 303. This table stores the measured amount of toner actually consumed from a test chart or the like so that the amount of usage with little deviation can be calculated.

  In step S <b> 102, the CPU 407 determines the sheet size 603 of the table obtained in step S <b> 101 from the image image size sent and printed from the data processing apparatus 101 via the host I / F unit 402.

  In step S <b> 103, the CPU 407 confirms the presence or absence of image data for which the toner usage amount has not been calculated in the image image that has been sent and printed by the data processing apparatus 101. If it is determined that there is image data for which the toner usage amount has not been calculated (Yes in S103), the CPU 407 advances the process to S104.

  In S <b> 104, the CPU 407 calculates the ratio of the number of effective dots in units of blocks in which one line or a plurality of lines in the main scanning direction are collected. In this embodiment, the line or block image data is run-length compressed by a one-dimensional encoding method (MH compression) or a two-dimensional compression method (MMR compression), and the white data (white run) obtained by the compression is effective. A method of obtaining the composition ratio from the pixel (black run) was adopted. That is, in this embodiment, run length compression is performed for each page in the print data in units of lines or blocks, and the occupation ratio of black pixels is obtained from the composition ratio of black pixels and white pixels.

  Next, in S105, the CPU 407 uses the line or block in the image image from the toner usage calculation table 601 obtained in S101, the paper size 603 obtained in S102, and the occupation rate 602 obtained in S104 ( The amount of use 604 predicted to be consumed) is derived.

  Next, in S106, the CPU 407 executes correction processing for the toner usage amount 604 obtained in S105. In the present embodiment, the dispersion of effective pixels in FIG. 8 (if the effective pixels are scattered, the compression ratio of run-length compression is reduced. In addition, the characteristic that the compression ratio of run-length compression increases for data with little dispersion) The correction method was adopted. Further, the correction value is a method that can be set by the user, but this method is not particular. For example, it is also possible to use a method of correcting according to the usage environment such as how the printing density is used, the type of paper to be used, and the humidity and temperature obtained from the environmental sensor 504.

  Next, in S107, the CPU 407 adds the toner usage corrected in S106 to the total value in order to accumulate in units of jobs, and then returns to S103 to process the next line or block. If it is determined in S103 that there is no image data for which the consumable usage amount has not been calculated, the CPU 407 ends this process.

(Description of processing for correcting toner usage (consumption))
FIG. 6 is a flowchart showing the processing for correcting the usage amount in the toner usage amount calculation unit 414 and showing the detailed procedure of the toner usage amount correction processing performed in S106 of FIG. This flowchart process is executed by the CPU 407 of the controller 302.

  First, in step S201, the CPU 407 in the controller 302 determines whether or not the dispersion of effective pixels is large for the data subjected to run length compression in step S104 in FIG. In the present embodiment, “large dispersion” is determined to correspond to the case where the size of the result of the run-length compression is larger than a certain threshold (that is, the compression rate of the run-length compression is low).

  In S201, when it is determined that the dispersion of effective pixels is large (that is, the compression ratio of the run length compression is low) (Yes in S201), the CPU 407 advances the process to S202. In S202, the CPU 407 acquires the corresponding correction value 702 from the toner usage amount correction table 701 in FIG. 8, and the process proceeds to S206.

  On the other hand, when it is determined in S201 that the dispersion of effective pixels is not large (No in S201), the CPU 407 advances the process to S203. In S203, the CPU 407 determines whether or not the dispersion of effective pixels is a normal value (normal) for the data subjected to the run length compression in S104 of FIG. In this embodiment, the configuration is such that the size of the result of the run length compression is determined to correspond to the normal value (that is, the run length compression rate is an appropriate amount).

  In S203, if it is determined that the dispersion of effective pixels is normal (that is, the compression ratio of run-length compression is moderate (medium)) (Yes in S203), the CPU 407 advances the process to S204. In S204, the CPU 407 acquires the corresponding correction value 703 from the toner usage correction table 701 in FIG. 8, and the process proceeds to S206.

  On the other hand, if it is determined in S201 that the dispersion of effective pixels is not normal (that is, the compression ratio of run-length compression is moderate (medium)) (No in S203), the CPU 407 advances the process to S205. In step S205, the CPU 407 acquires the corresponding correction value 704 from the toner usage amount correction table 701 in FIG. 8, and proceeds to step S206.

  Next, in S206, the CPU 407 stores data indicating the presence of correction in the correction values (correction values 702, 703, and 704 in FIG. 8) acquired in S202, S204, or S205 (valid data in the correction values). Whether or not there is).

  If it is determined that data indicating that there is correction is stored (the correction value includes valid data) (Yes in S206), the CPU 407 advances the process to S207. In S207, the CPU 407 performs a correction process using the value stored in the correction value 702, 703, or 704 in FIG. 8 for the usage amount 604 obtained in S105 in FIG. 5, and ends this process.

  On the other hand, if it is determined that data indicating that there is correction is not stored (“no correction” in which there is no valid data in the correction value) (No in S206), the CPU 407 advances the process to S208. In S208, the CPU 407 ends the present process without performing the correction process for the usage amount 604 obtained in S105 of FIG.

(Explanation of table for calculating toner usage)
FIG. 7 is a diagram illustrating an example of a toner usage amount calculation table according to the present exemplary embodiment. The toner usage calculation table is stored in, for example, the nonvolatile memory EEPROM 410 and can be accessed by the CPU 407 in the controller 302. In addition, the toner usage calculation table is configured to store a value obtained by actually measuring the toner usage actually consumed from a test chart or the like, and to calculate a usage with little deviation.

This toner usage amount calculation table 601 exists for each engine type, and is configured such that the toner usage amount 604 can be derived from the effective dot occupancy 602 and the paper size 603.
In this embodiment, the effective dot occupancy 602 is set to 0%, 25%, 50%, 75%, 100% and 25% increments, but this is not particular, and the unit is 10% or 5%. For example, the calculation may be performed in a finer range.

  Further, the toner usage amount 604 in this embodiment can be calculated in fine units by storing the usage amount in units of lines or blocks, and the usage amount with little deviation from the toner amount actually used is predicted ( Calculation).

(Description of table for correcting toner usage)
FIG. 8 is a toner use amount correction table of this embodiment. The toner usage correction table is stored in, for example, the nonvolatile memory EEPROM 410 and can be accessed by the CPU 407 of the controller 302. In addition, the toner usage amount correction table is configured so that the user can adjust the value on the screen shown in FIG. 9 so that the deviation from the actually used toner amount is reduced.

  In this embodiment, in order to correct the amount of toner used, the correction can be made according to the dispersion of effective pixels. Note that, as a condition for determining the degree of dispersion of effective pixels, the run-length compression rate decreases when the effective pixels are scattered. In addition, the characteristic that the compression rate of run length compression is increased is used for data with little dispersion.

  When the compression ratio of the run length compression is low, a correction value of 702 of “large scattering” is used. When the compression rate is appropriate, the value 703 is used for normal correction. Further, when the compression ratio of the run length compression is high, a correction value of 704 of “scattered small (dense)” is used. In this embodiment, the correction values 702, 703, and 704 can be updated and set on the toner use amount correction value setting screen 801.

(Explanation of mechanism for setting / updating values for correcting toner usage)
FIG. 9 is a toner use amount correction value setting screen of the present embodiment. The toner use amount correction value setting screen is displayed on the panel unit 301 via the panel I / F unit 401 under the control of the CPU 407 of the controller 302, and allows setting and updating of values from a user who is an operator. It should be noted that the values set on this screen are stored in the toner usage correction table 702, 703, 704 in FIG. 8 and held in the nonvolatile memory EEPROM 410.

  In FIG. 9, reference numeral 801 denotes a toner usage correction value setting screen, which is displayed on the panel unit 301 via the panel I / F unit 401 by the CPU 407 of the controller 302. Reference numeral 802 denotes a correction value when effective pixels are scattered (scattered “large”), and is stored and held in 702 of FIG. Reference numeral 803 denotes a correction value used by the effective pixels in a normal dispersion state (scattering “normal (medium)”), and is stored and held in 703 in FIG. 7. Reference numeral 804 denotes a correction value when effective pixels are dense (scattered “small”), and is stored and held in 704 in FIG. In this embodiment, 802 to 804 are configured to be able to increase / decrease the correction value in units of “no correction” or “0.05%”. However, the present invention is not limited to this configuration. Can be any number.

  A setting instruction button 805 is used to write a value set on this screen into the nonvolatile memory EEPROM 410. Reference numeral 806 denotes a return button for returning the display to the previous screen without writing the value set on this screen to the nonvolatile memory EEPROM 410.

In the above embodiment, the toner is used as an example of the printing agent. However, the present invention can be applied to printing agents other than toner. For example, the present invention can be applied even when ink is used as a printing agent.
In the above embodiment, the description has been given focusing on only one type of printing agent, but in the case of an image forming apparatus capable of forming an image using a plurality of printing agents, the processing shown in FIG. 4 is performed for each printing agent. The remaining amount of printing agent is obtained for each printing agent.

  In this case, for each printing agent, the controller 302 determines, for each page in the printing data, the occupation ratio of the pixels to be printed by the printing agent from the composition ratio of the pixels to be printed by the printing agent and other pixels in units of lines or blocks. Ask. In addition, the controller 302 obtains the printing agent consumption for each printing agent from the occupation ratio and the paper size used for printing. Further, the controller 302 corrects the calculated consumption amount of the printing agent for each printing agent by using a correction value corresponding to the degree of scattering of pixels printed by the printing agent. Further, the controller 302 obtains the remaining amount of the printing agent by using the corrected printing agent consumption for each printing agent.

  In the above-described embodiment, a configuration is shown in which the consumption amount of the printing agent corresponding to the effective dot occupancy rate and the paper size used for printing is obtained using the toner usage amount calculation table (FIG. 7). However, for each paper size, a calculation formula for calculating the toner usage from the effective dot occupancy rate is prepared, and the effective dot occupancy rate and printing are calculated using the calculation formula corresponding to the paper size used for printing. You may make it obtain | require the consumption of the printing agent corresponding to the paper size used for.

  With the above configuration, the consumption amount of the printing agent such as toner or ink can be accurately calculated. Then, the remaining amount of the printing agent in the printing agent container (for example, the remaining amount of toner in the toner container) is accurately obtained, and notification such as a remaining amount display with little deviation (error) from the physical remaining amount is given to the user or the like. Can do. According to the present invention, even in an image forming apparatus that does not include a dot counter, it is possible to accurately determine the amount of printing agent consumed, and to accurately determine the remaining amount of printing agent in the printing agent container. Can do.

It should be noted that the configuration and contents of the various data described above are not limited to this, and it goes without saying that the various data and configurations are configured according to the application and purpose.
Although one embodiment has been described above, the present invention can take an embodiment as, for example, a system, apparatus, method, program, or storage medium. Specifically, the present invention may be applied to a system composed of a plurality of devices, or may be applied to an apparatus composed of a single device.
Moreover, all the structures which combined said each Example are also contained in this invention.

(Other examples)
The present invention can also be realized by executing the following processing. That is, software (program) that realizes the functions of the above-described embodiments is supplied to a system or apparatus via a network or various storage media, and a computer (or CPU, MPU, or the like) of the system or apparatus reads the program. It is a process to be executed.
Further, the present invention may be applied to a system composed of a plurality of devices or an apparatus composed of a single device.
The present invention is not limited to the above embodiments, and various modifications (including organic combinations of the embodiments) are possible based on the spirit of the present invention, and these are excluded from the scope of the present invention. is not. That is, the present invention includes all the combinations of the above-described embodiments and modifications thereof.

Claims (6)

An image forming apparatus,
For each page in the print data, a calculation unit that performs run length compression in units of lines or blocks and obtains the black pixel occupancy ratio from the composition ratio of black pixels and white pixels;
Using a table, a predicting means for obtaining a consumption amount of toner corresponding to the occupation ratio obtained by the calculating means and a paper size used for printing;
Acquisition means for acquiring a correction value corresponding to the degree of dispersion of the black pixels with reference to a correction table;
Correction means for correcting the toner consumption determined by the prediction means using the correction value acquired by the acquisition means;
An image forming apparatus comprising:   The image forming apparatus according to claim 1, further comprising: a remaining amount calculating unit that obtains a remaining amount of toner of the image forming apparatus using the toner consumption corrected by the correcting unit.   The image forming apparatus according to claim 1, further comprising a setting unit configured to set a correction value for each degree of black pixel dispersion in the correction table.   The remaining amount calculating means reads out the amount of toner stored in the cartridge from a memory provided in the cartridge and sets it as the remaining amount of toner when the cartridge storing the toner is replaced. The image forming apparatus according to claim 2 or 3. An image forming apparatus control method comprising:
For each page in the print data, a calculation step of performing run-length compression in units of lines or blocks and obtaining an occupancy ratio of black pixels from a composition ratio of black pixels and white pixels;
Using a table, a prediction step for obtaining a toner consumption amount corresponding to the occupation ratio obtained in the calculation step and a paper size used for printing;
An acquisition step of acquiring a correction value corresponding to the degree of scattering of the black pixels with reference to a correction table;
A correction step of correcting the toner consumption determined in the prediction step using the correction value acquired in the acquisition step;
A control method for an image forming apparatus, comprising:   The program for functioning a computer as a means as described in any one of Claims 1 thru | or 4.

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