Image forming device, and information processing device

Abstract

To predict a residual amount of a developer with high accuracy.SOLUTION: An image forming apparatus includes an image formation part (20) forming an image based on image data on a transfer material by using a developer, a data processing part 406 for calculating a consumption amount of the developer on the basis of the image data, and a toner amount management part 405 for calculating a correction value α of a toner consumption amount per 1 dot by a total soft count value X showing an amount of the developer stored by a new image formation part (20) and a total soft count value Y obtained by integrating consumption amounts. The toner amount management part 405 calculates a prediction value of a use amount of the developer by the total soft count value X, the total soft count value Y, and the correction value α, and calculates a residual amount of the developer by the prediction value.SELECTED DRAWING: Figure 4

Description

[Technical Field]

[0001] The present invention relates to an image forming apparatus such as a printer, a copying machine, a facsimile machine, or a multifunction machine. [Background technology]

[0002] Some electrophotographic image forming apparatuses calculate the amount of developer consumed each time an image is formed and display the remaining amount of developer on a display unit. One method for detecting the remaining amount of developer is to use a sensor. When using a sensor, mechanical constraints arise due to the need to make the image forming apparatus smaller and more space-saving. In addition, costs are expected to increase due to the addition of parts and design changes. For this reason, methods have been proposed for estimating the amount of developer consumed from image data representing the image to be formed. Patent Documents 1 and 2 exemplify such estimation methods.

[0003] Patent Document 1 discloses a toner consumption calculation method that calculates the density value of each pixel from image data before halftone correction processing, and calculates the toner consumption for each pixel from the calculated density value. This toner consumption calculation method calculates the toner consumption for each page by integrating the toner consumption for each pixel for each page. The halftone correction process corrects the input signal value so that the relationship between the input signal value and image density in the gradation area becomes an ideal, constant state. This toner consumption calculation method calculates the toner consumption for the gradation area with high accuracy by calculating the toner consumption using image data before halftone correction processing.

[0004] Patent Document 2 discloses a method for calculating toner consumption that takes into account the phenomenon (edge ​​effect) in which print dots located at the edge of an image consume more toner than print dots in so-called solid areas. This toner consumption calculation method prepares a weighting factor for each pixel in advance depending on the continuity of the print pixels. The toner consumption per pixel is calculated by multiplying each pixel by the corresponding weighting factor, and this is then added up for all pixels included in the image to calculate the toner consumption for one page of image. This toner consumption calculation method can accurately calculate the toner consumption in text areas that are strongly affected by the edge effect. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Application Laid-Open No. 2007-114593 [Patent Document 2] Japanese Patent Application Laid-Open No. 2009-98185 Summary of the Invention [Problem to be solved by the invention]

[0006] The toner consumption calculation method of Patent Document 1 can accurately calculate toner consumption in gradation areas, but does not accurately calculate toner consumption in areas strongly affected by edge effects (e.g., text areas). Conversely, the toner consumption calculation method of Patent Document 2 can accurately calculate toner consumption in text areas, but does not accurately calculate toner consumption in gradation areas where on-off patterns are densely repeated and complex dot patterns are present. Furthermore, the amount of toner consumed by actual development is not necessarily constant due to variations in the environment and device characteristics. This results in errors between the estimated toner consumption and the actual toner consumption. Typically, toner is deposited on the photoconductor from the developing device. Errors in the estimated toner consumption reduce the accuracy of predicting the remaining toner amount in the developing device.

[0007] In view of the above-mentioned problems, an object of the present invention is to predict the remaining amount of developer with high accuracy. [Means for solving the problem]

[0008] The image forming apparatus of the present invention is characterized by comprising: an image forming means for forming an image based on image data on a transfer material using a developer; a data processing means for calculating the amount of developer consumed based on the image data; and a management means for calculating a correction value for the amount of toner consumed per dot based on a count value indicating the amount of developer contained in a new image forming means and an integrated value of the consumed amount, calculating a predicted value for the amount of developer used based on the count value, the integrated value, and the correction value, and calculating the remaining amount of developer based on the predicted value. [Effects of the Invention]

[0009] According to the present invention, the remaining amount of developer can be predicted with high accuracy. [Brief explanation of the drawings]

[0010] [Figure 1] FIG. 1 is a diagram illustrating the configuration of an image forming apparatus. [Figure 2] FIG. 2 is a diagram illustrating the configuration of a printer engine. [Figure 3] FIG. [Figure 4] FIG. 2 is an explanatory diagram of a video controller. [Figure 5] FIG. [Figure 6] FIG. 4 is an explanatory diagram of an image density correction processing unit. [Figure 7] FIG. 4 is an explanatory diagram of a first toner amount calculation unit. [Figure 8] FIG. 10 is an explanatory diagram of a first toner consumption amount. [Figure 9] FIG. 10 is a diagram illustrating a weighting coefficient table. [Figure 10] FIG. 4 is an explanatory diagram of a second toner amount calculation unit. [Figure 11] FIG. 10 is a diagram illustrating the relationship between the number of consecutive print dots and a correction coefficient. [Figure 12] 10 is a flowchart showing a remaining toner amount calculation process. [Figure 13] 10 is a flowchart showing a process of updating the remaining amount of toner. [Figure 14] 10 is a flowchart showing a process for obtaining a total soft count value X. [Figure 15] 10 is a flowchart showing a process for obtaining a total soft count value Y. [Figure 16] 10 is a flowchart showing a process of updating a correction value α of a toner consumption coefficient. [Figure 17] 10 is a flowchart showing a process for calculating a predicted value Z of a toner usage amount. [Figure 18] An explanatory diagram of the effect. [Figure 19] 10 is a flowchart showing a process of updating a correction value α of a toner consumption coefficient. [Figure 20] 10 is a flowchart showing a process of updating a correction value α of a toner consumption coefficient. DETAILED DESCRIPTION OF THE INVENTION

[0011] Preferred embodiments of the present invention will be described in detail below with reference to the drawings. However, unless otherwise specified, the relative positions and numerical values ​​of the components described in the embodiments are not intended to limit the scope of the present invention.

[0012] (Image forming device) FIG. 1 is a diagram illustrating the configuration of an image forming apparatus according to this embodiment. The image forming apparatus 102 according to this embodiment is a color image forming apparatus that forms images using four colors: yellow (Y), magenta (M), cyan (C), and black (K). The image forming apparatus 102 may be a monochrome image forming apparatus that uses clear toner, gold toner, or silver toner. In this embodiment, the image forming apparatus 102 is described as printing at a resolution of 600 dpi, but the resolution is not limited to this.

[0013] The image forming apparatus 102 includes a video controller 103 that performs various controls and data processing, and a printer engine 104 that forms a visualized image on a transfer material. The transfer material is also called a recording material, recording medium, sheet, or transfer paper. The image forming apparatus 102 is connected to a host computer 101 and the like via a network, a parallel interface, a serial interface, or the like. The host computer 101 instructs the image forming apparatus 102 to execute printing. The video controller 103 rasterizes print data sent from the host computer 101 together with the print execution instruction into image data, performs data processing (described below), and sends the data to the printer engine 104.

[0014] (printer engine) FIG. 2 is a configuration diagram of the printer engine 104. FIG. 3 is an explanatory diagram of a control unit that controls the operation of the printer engine 104. The printer engine 104 of this embodiment uses four colors of toner: yellow, magenta, cyan, and black, as developers. The printer engine 104 is a tandem type in which four image forming units 20Y, 20M, 20C, and 20K corresponding to the four colors, yellow, magenta, cyan, and black, are arranged along the intermediate transfer body 27. The four image forming units 20Y, 20M, 20C, and 20K have the same configuration. The four image forming units 20Y, 20M, 20C, and 20K and their respective components are designated by their reference numerals with Y, M, C, and K suffixed to their respective reference numerals to distinguish between the corresponding colors. However, when it is not necessary to describe each color separately, the Y, M, C, and K suffixes are omitted from the reference numerals.

[0015] The printer engine 104 includes an engine control unit 301 and an engine mechanism unit 302. The engine mechanism unit 302 operates in accordance with various instructions received from the engine control unit 301, thereby controlling image formation on the transfer material 11.

[0016] The engine mechanism unit 302 includes a laser scanner system 308, an image creation system 309, a paper feed and transport system 310, and a sensor system 311. An image is formed on the transfer material 11 by the laser scanner system 308 and the image creation system 309. The paper feed and transport system 310 transports the transfer material 11 during image formation. The sensor system 311 includes a plurality of sensors that monitor the operation of each part of the engine mechanism unit 302. The detection results by the sensor system 311 are sent to the engine control unit 301.

[0017] The image forming system 309 of the engine mechanism unit 302 has four image forming units 20, an intermediate transfer body 27, a transfer roller 28 that transfers a toner image to the transfer material 11, and a fixing unit 30. The image forming system 309 also has a high-voltage power supply that generates various bias voltages (high voltages) required for image formation. The laser scanner system 308 of the engine mechanism unit 302 has an exposure unit 24.

[0018] Each of the four image forming units 20 is configured as an integral unit of a photosensitive drum 22, a charger 23, and a developing unit 26, and is a cartridge that is detachable from the main body of the printer engine 104. Therefore, when replacing an image forming unit 20, the photosensitive drum 22, the charger 23, and the developing unit 26 are replaced all at once. Each of the four image forming units 20 has a nonvolatile memory device.

[0019] The photosensitive drum 22 is a drum-shaped photosensitive element having a photosensitive layer on its surface, and rotates around the drum axis. The charger 23 uniformly charges the surface of the rotating photosensitive drum 22. The charger 23 has a charging sleeve 23S, and charges the photosensitive drum 22 by applying a bias voltage to the charging sleeve 23S. The photosensitive drum 22, whose surface is uniformly charged, is exposed by an exposure device 24 (described below), and an electrostatic latent image corresponding to image data is formed. The developer 26 visualizes the electrostatic latent image formed on the photosensitive drum 22 by applying toner as a developer to the electrostatic latent image. The developer 26 contains toner as a developer and has a developing sleeve 26S. The developing sleeve 26S applies the toner to the electrostatic latent image. In this way, a toner image is formed on the photosensitive drum 22.

[0020] The exposure unit 24 has a laser light-emitting element, a laser driver, a scan motor, a rotary polygon mirror, and a scan driver. The exposure unit 24 causes the laser light-emitting element to emit laser light based on a laser drive signal, and exposes and scans the photosensitive drum 22 by reflecting the laser light off the rotary polygon mirror. The laser drive signal indicates an exposure time of the laser light, and is obtained from the video controller 103. An electrostatic latent image is formed on the surface of the photosensitive drum 22 by selectively exposing the surface of the photosensitive drum 22 to the laser light.

[0021] The toner images formed on the photosensitive drums 22Y, 22M, 22C, and 22K of the image forming units 20Y, 20M, 20C, and 20K are superimposed and transferred to the intermediate transfer body 27. A yellow toner image is formed on the photosensitive drum 22Y. A magenta toner image is formed on the photosensitive drum 22M. A cyan toner image is formed on the photosensitive drum 22C. A black toner image is formed on the photosensitive drum 22K. The toner images of each color transferred to the intermediate transfer body 27 are transferred together onto the transfer material 11 by the transfer roller 28. The transfer material 11 onto which the toner images have been transferred is fixed by the fixer 30.

[0022] The intermediate transfer body 27 is an endless belt that is wound around a plurality of rollers, including a drive roller 25. The intermediate transfer body 27 is driven to rotate by the drive roller 25, and toner images are transferred sequentially from the photosensitive drums 22Y, 22M, 22C, and 22K onto the intermediate transfer body 27. As the intermediate transfer body 27 rotates, it transports the transferred toner images to a transfer roller 28. The transfer material 11 is transported to the transfer roller 28 in accordance with the timing at which the toner images are transported by the intermediate transfer body 27. A cleaning unit 29 is provided downstream of the transfer roller 28 in the rotation direction of the intermediate transfer body 27.

[0023] The transfer roller 28 rotates with the transfer material 11 sandwiched between it and the intermediate transfer body 27, so that the transfer material 11 is sandwiched and transported between the intermediate transfer body 27 and the transfer roller 28. At this time, a transfer bias voltage is applied to the transfer roller 28, so that the four color toner images on the intermediate transfer body 27 are transferred all at once to the transfer material 11. The transfer roller 28 is biased toward the intermediate transfer body 27 to contact the transfer material 11 while the toner image is being transferred onto the transfer material 11, and then moves away from the intermediate transfer body 27 once the transfer is complete. The transfer material 11 onto which the toner image has been transferred is transported to a fixing device 30. A cleaning unit 29 removes any toner remaining on the intermediate transfer body 27 after each transfer.

[0024] The fixing unit 30 includes a fixing roller 31 that heats the transfer material 11, and a pressure roller 32 that presses the transfer material 11 against the fixing roller 31. The fixing roller 31 and the pressure roller 32 are hollow, and heaters 33 and 34 are provided inside them, respectively. The fixing unit 30 sandwiches and conveys the transfer material 11 between the fixing roller 31 and the pressure roller 32. At this time, the transfer material 11 is heated by the heaters 33 and 34, and the transfer material 11 is pressed by the fixing roller 31 and the pressure roller 32. As a result, the toner image is melted and fixed onto the transfer material 11. The transfer material 11 with the image fixed by the fixing unit 30 is discharged outside the image forming apparatus 102 as a printed matter.

[0025] The paper feed conveyance system 310 feeds and conveys the transfer material 11. The paper feed conveyance system 310 includes various conveyance motors, a paper feed unit (paper feed cassette 21a and paper feed tray 21b), and various conveyance rollers including a paper feed roller and a paper discharge roller. The paper feed conveyance system 310 feeds the transfer material 11 one sheet at a time from the paper feed cassette 21a or paper feed tray 21b to the transfer roller 28 in accordance with the operation of the image creation system 309.

[0026] The sensor system 311 is a group of sensors for collecting information necessary for controlling the laser scanner system 308, the image creation system 309, and the paper feed / transport system 310. The group of sensors includes a temperature sensor for detecting the fixing temperature of the fixing unit 30, an image density sensor 40 for detecting the image density of the toner image, a sensor for detecting color misregistration, a paper size sensor, a paper leading edge detection sensor, a paper transport detection sensor, etc. In this embodiment, the image density sensor 40 is provided downstream of the photosensitive drum 22K in the rotation direction of the intermediate transfer body 27 to detect the image density of the toner image formed on the intermediate transfer body 27. Note that the image density sensor 40 may also be provided in a position for detecting the image density of the toner image formed on the photosensitive drum 22 or the transfer material 11. The detection results obtained by the sensor system 311 are sent to the engine control unit 301.

[0027] The engine control unit 301 is an information processing device including a CPU (Central Processing Unit) 303, RAM (Random Access Memory) 305, and non-volatile memory 306. The engine control unit 301 also includes an ASIC (Application Specific Integrated Circuit) 304, which is a dedicated device for controlling the operation of the engine mechanism unit 302, and an engine I / F 307. The CPU 303 and ASIC 304 write and read various information to and from non-volatile memory devices provided in each of the four image forming units 20Y, 20M, 20C, and 20K. The various information includes the number of images formed, operating time, cartridge type, remaining amount of toner, remaining life, etc. The engine I / F 307 is a communication interface that controls communication between the engine control unit 301 and the video controller 103.

[0028] The CPU 303, ASIC 304, RAM 305, memory 306, and engine I / F 307 are connected to each other so as to be able to communicate with each other via a system bus 312. The components of the engine mechanism unit 302 are also connected to the system bus 312, and communication between the engine control unit 301 and the engine mechanism unit 302 is carried out via the system bus 312. The system bus 312 has an address bus and a data bus.

[0029] The CPU 303 uses the RAM 305 as a main memory and a work area, and executes various control programs stored in the memory 306 to control the operation of the engine mechanism unit 302. The CPU 303 acquires the detection results detected by the sensor system 311 and controls the print sequence.

[0030] When the CPU 303 receives a print execution instruction from the video controller 103 via the engine I / F 307, it first drives the image forming system 309 and charges the surface of the photosensitive drum 22 with the charger 23. The CPU 303 drives the laser scanner system 308 with a laser drive signal generated based on the image data, and forms an electrostatic latent image on the photosensitive drum 22 with the exposure unit 24.

[0031] Next, CPU 303 drives image creation system 309, causing developer 26 to develop the electrostatic latent image and form monochromatic toner images of the colors corresponding to each of photosensitive drums 22Y, 22M, 22C, and 22K. CPU 303 causes image creation system 309 to transfer these monochromatic toner images to intermediate transfer body 27 in a sequential, superimposed manner, thereby forming a multicolor toner image on intermediate transfer body 27. Simultaneously with driving image creation system 309, CPU 303 controls paper feed conveyance system 310, causing paper feed rollers to feed transfer material 11 from the paper feed unit. CPU 303 causes image creation system 309 to transfer the multicolor toner image to transfer material 11, and then controls fuser 30 to fuse the multicolor toner image on transfer material 11.

[0032] In response to instructions from the CPU 303, the ASIC 304 controls each motor and high-voltage power supplies such as developing bias, which are necessary for executing various printing sequences. The ASIC 304 controls the operation of the engine mechanism unit 302 by operating in cooperation with the CPU 303. Note that the ASIC 304 may have at least some of the functions of the CPU 303, and conversely, the CPU 303 may have at least some of the functions of the ASIC 304. Furthermore, at least some of the functions of the CPU 303 and the ASIC 304 may be realized by separate dedicated hardware.

[0033] (Video Controller) 4 is an explanatory diagram of the video controller 103. The video controller 103 is an information processing device including a CPU 401, a memory 402, and a RAM 403. The video controller 103 includes a host I / F 404, a toner amount management unit 405, an image density correction processing unit 411, a data processing unit 406, a DMA control unit 407, an operation display unit 408, and an engine I / F 409. The components of the video controller 103 are connected to each other so as to be able to communicate with each other via a system bus 410. The system bus 410 has an address bus and a data bus.

[0034] The CPU 401 controls the operation of the video controller 103 by executing computer programs stored in the memory 402. The memory 402 is nonvolatile and stores various control codes (computer programs) executed by the CPU 401 and data used for control. The memory 402 is configured, for example, with a ROM (Read Only Memory), an EEPROM (Electrically Erasable Programmable Read-Only Memory), a hard disk, etc. The RAM 403 functions as the main memory, work area, etc. of the CPU 401.

[0035] The host I / F 404 is a communication interface that acquires print execution instructions, print data, control data, etc. from the host computer 101. The print data received by the host I / F 404 is stored in the RAM 403. The print data is bitmap data that has undergone halftone processing by the host computer 101 or the like, or PDL (page description language) data. PDL data is data written in a page description language for creating image data. The print data usually includes image rendering commands for characters, graphics, images, etc.

[0036] In response to an instruction from the CPU 401, the DMA control unit 407 transfers data stored in the RAM 403 to the engine I / F 409 and the data processing unit 406. In response to an instruction from the CPU 401, the data processing unit 406 performs various types of data processing (e.g., estimating toner consumption) using image data acquired from the RAM 403. The detailed operation of the data processing unit 406 will be described later.

[0037] The operation display unit 408 is a user interface provided on the main body of the image forming apparatus 102. The operation display unit 408 accepts various settings and instructions input from the user via an input interface, and displays various information about the image forming apparatus 102 via an output interface. The engine I / F 409 is a communication interface with the printer engine 104. The engine I / F 409 transmits, for example, a laser drive signal output from the data processing unit 406 to the printer engine 104.

[0038] The toner amount management unit 405 updates and manages the remaining toner amounts in the developers 26Y, 26M, 26C, and 26K of the image forming units 20Y, 20M, 20C, 20K, and 20K based on the toner consumption amount for each page notified from the data processing unit 406. The updated remaining toner amounts are displayed on the operation display unit 408, thereby notifying the user of the remaining toner amounts. The toner amount management unit 405 may also notify the host computer 101 of the remaining toner amounts via the host I / F 404.

[0039] The image density correction processing unit 411 performs image density correction processing in response to an instruction from the CPU 401 or an instruction from the printer engine 104 via the engine I / F 409. The image density correction processing unit 411 generates a gradation correction table used during image density correction through the image density correction processing. The detailed operation of the image density correction processing unit 411 will be described later.

[0040] The functions of the data processing unit 406 may be realized as an ASIC or dedicated hardware, or at least a part of the functions may be realized by the CPU 401. Furthermore, at least a part of the functions of the video controller 103 may be realized by an external device such as the host computer 101.

[0041] (Data Processing Unit) 5 is an explanatory diagram of the data processing unit 406. The data processing unit 406 includes a RIP (Raster Image Processor) unit 501, a color conversion unit 502, an image density correction unit 503, a halftone unit 504, and a PWM (Pulse Width Modulation) unit 506. These components perform predetermined image processing on image data and are used to generate a laser drive signal, which is a PWM signal that controls the light emission of the exposure unit 24. The data processing unit 406 also includes a first toner amount calculation unit 510, a second toner amount calculation unit 505, and a printing rate calculation unit 511, which calculate the amount of toner to be consumed from the image data.

[0042] The RIP unit 501 analyzes image data written in PDL (PDL data) obtained from the RAM 403 to generate intermediate language data, and then rasterizes the intermediate language data to generate raster image data. The raster image data is saved in a predetermined area in the RAM 403 as image data for each color of R (red), G (green), and B (blue).

[0043] The color conversion unit 502 performs color matching processing to convert the image data for each color stored in the RAM 403 into a device RGB signal that matches the color reproduction gamut of the image forming device 102. Furthermore, the color conversion unit 502 converts the device RGB signal into a YMCK signal, which is the toner color of the image forming device 102. In this way, the color conversion unit 502 converts the image data for each color of RGB generated by the RIP unit 501 into image data for each color of Y, M, C, and K, in order, and stores the converted data in a predetermined area in the RAM 403.

[0044] The image density correction unit 503 performs halftone correction processing by converting the image data of each color of Y, M, C, and K stored in the RAM 403 using a gradation correction table. This processing is performed to establish a predetermined relationship between the gradation values ​​of the image data of each color of Y, M, C, and K and the density of the image output onto the transfer material 11 by the printer engine 104.

[0045] The halftone unit 504 performs halftone processing (ordered dithering, etc.) on the multi-value (here, 8 bits) image data for each of the colors Y, M, C, and K corrected by the image density correction unit 503. Through halftone processing, the image data for each of the colors Y, M, C, and K is quantized into 1-bit image data that can be reproduced by the printer engine 104. The 1-bit image data is stored in the image memory in the RAM 403. The PWM unit 506 converts the 1-bit image data after halftone processing, stored in the image memory, into a laser drive signal (laser exposure time) through PWM processing.

[0046] First toner amount calculation unit 510 calculates the amount of toner consumed per page for each color (first toner consumption amount) based on the image data for each color of Y, M, C, and K generated by color conversion unit 502 and stored in RAM 403. Printing rate calculation unit 511 calculates the printing rate for each color per page based on the toner consumption per page for each color calculated by first toner amount calculation unit 510. Second toner amount calculation unit 505 calculates the amount of toner consumed per page for each color (second toner consumption amount) based on the 1-bit image data for each color of Y, M, C, and K generated by halftone unit 504.

[0047] The first and second toner consumption amounts calculated by first toner amount calculation unit 510 and second toner amount calculation unit 505, and the printing rate calculated by printing rate calculation unit 511 are sent to toner amount management unit 405. Detailed operations of first toner amount calculation unit 510, printing rate calculation unit 511, second toner amount calculation unit 505, and toner amount management unit 405 will be described later.

[0048] (Image density correction processing unit) 6 is an explanatory diagram of the image density correction processing unit 411. The image density correction processing unit 411 has a gradation characteristic detection unit 601 and a correction table calculation unit 602. The image density correction processing unit 411 creates a gradation correction table used in processing by the image density correction unit 503 and stores it in the RAM 403.

[0049] The gradation characteristic detection unit 601 detects the gradation characteristic of the image forming apparatus 102 (gamma characteristic of the printer engine 104). The image forming apparatus 102 forms an image for detection on the intermediate transfer body 27. This image for detection is stored in advance in the memory 306 (FIG. 3) for each toner color. This image for detection is read by the image density sensor 40. The gradation characteristic detection unit 601 acquires data regarding the image density of the image for detection (density data) from the reading result of the image for detection read by the image density sensor 40. The gradation characteristic detection unit 601 generates gradation characteristics (gamma characteristic of the printer engine 104) that correspond to the density data and the gradation level of the image for detection for each color. The gradation characteristic detection unit 601 transmits the generated gradation characteristic to the correction table calculation unit 602.

[0050] The correction table calculation unit 602 generates a gradation correction table that converts image data so that the measured gradation characteristics of the printer engine 104 become ideal gradation characteristics, based on the gradation characteristics (gamma characteristics) acquired from the gradation characteristics detection unit 601. Here, the method of generating the gradation correction table from the gradation characteristics (gamma characteristics) acquired from the gradation characteristics detection unit 601 and the ideal gradation characteristics may be performed using a known technique. Therefore, a detailed description of the method of generating the gradation correction table will be omitted. The correction table calculation unit 602 records the newly generated gradation correction table in the memory 402 (FIG. 4).

[0051] Using the tone correction table thus generated, the image density correction unit 503 converts each tone value of the image data for each color of Y, M, C, and K. An image is then formed based on the converted image data. This maintains a predetermined ideal relationship between each tone value of the image data for each color of Y, M, C, and K and the density of the image formed on the transfer material 11, regardless of variations in the gamma characteristics of the image forming device 102 (printer engine 104) or changes over time.

[0052] (Video controller operation) The video controller 103 configured as above receives a print execution instruction from the host computer 101 and transmits data necessary for image formation to the printer engine 104. The flow of such processing will be described below.

[0053] The video controller 103 acquires a print execution instruction from the host computer 101 via the host I / F 404. When the CPU 401 of the video controller 103 acquires the print execution instruction, the CPU 401 acquires print data from the host computer 101 via the host I / F 404. The CPU 401 stores the acquired print data in the RAM 403.

[0054] The CPU 401 controls the RIP unit 501 of the data processing unit 406 to rasterize the image data stored in the RAM 403. The CPU 401 controls the color conversion unit 502 to perform color conversion processing on the rasterized image data. The CPU 401 controls the image density correction unit 503 to perform image density correction processing on the color-converted image data. The CPU 401 controls the halftone unit 504 to perform halftone processing on the image data after the image density correction processing. The CPU 401 controls the PWM unit 506 to perform PWM processing on the image data after the halftone processing.

[0055] CPU 401 transmits the laser drive signal generated by PWM processing to printer engine 104 via engine I / F 409. At the same time, CPU 401 controls first toner amount calculation unit 510 and second toner amount calculation unit 505 to calculate the toner consumption amount. CPU 401 controls printing rate calculation unit 511 to calculate the printing rate. CPU 401 causes first toner amount calculation unit 510, second toner amount calculation unit 505, and printing rate calculation unit 511 to notify toner amount management unit 405 of their respective calculation results.

[0056] (First toner amount calculation unit and printing rate calculation unit) The processing of the first toner amount calculation unit 510 and the printing rate calculation unit 511 will be described in detail. FIG. 7 is an explanatory diagram of the first toner amount calculation unit 510. Here, calculation of the first toner consumption amount for black (K) will be described, but the first toner consumption amounts for other chromatic colors (yellow, magenta, cyan) are calculated by similar processing. The first toner amount calculation unit 510 calculates the first toner consumption amount based on multi-value (8-bit) pixel values ​​obtained from the image data for black after color conversion processing stored in RAM 403. The image data for black after color conversion processing stored in RAM 403 is data before halftone correction processing by the image density correction unit 503. The first toner amount calculation unit 510 includes an image data correction unit 701, an accumulator 702, and a toner consumption calculation unit 703.

[0057] 8 is an explanatory diagram of the first toner consumption amount. The first toner consumption amount is correlated with the pixel value of the image data color converted by the color conversion unit 502. However, the inventors' studies have revealed that the first toner consumption amount does not have a proportional relationship with the pixel value of the image data color converted by the color conversion unit 502 as shown in graph L4, but has a nonlinear relationship as shown in graph L5. Therefore, the first toner amount calculation unit 510 uses the toner consumption amount required for a predetermined pixel value as a reference and calculates in advance a correction value weighted by a predetermined coefficient to eliminate the difference between the first toner consumption amount required for each pixel value and the reference toner consumption amount.

[0058] 9 is an example of a weighting coefficient table showing the correspondence between pixel values ​​(input pixel values) according to image data input to the first toner amount calculation unit 510 and weighted correction values ​​(corrected pixel values) corresponding to each pixel value. The weighting coefficient table allows the corrected pixel values ​​corresponding to the input pixel values ​​to be obtained.

[0059] The image data correction unit 701 acquires the color-converted image data (pixel values) from the RAM 403 and derives a corrected pixel value using the weighting coefficient table of Fig. 9. For example, when the pixel value of the image data after color conversion acquired from the RAM 403 is "31", the image data correction unit 701 acquires a corrected pixel value of "23" by referring to the weighting coefficient table. The image data correction unit 701 transmits the acquired corrected pixel value to the accumulator 702.

[0060] Accumulation unit 702 accumulates corrected pixel values ​​sequentially acquired from image data correction unit 701. Toner consumption calculation unit 703 calculates a first toner consumption amount using the accumulated value of the corrected pixel values ​​by accumulation unit 702 and a predetermined calculation formula. Toner consumption calculation unit 703 transmits the calculated first toner consumption amount to toner amount management unit 405.

[0061] The printing rate calculation unit 511 calculates the printing rate using the first toner consumption amount per page calculated by the toner consumption calculation unit 703, with the toner consumption amount when the image in the page is a full solid image as the reference. The printing rate calculation unit 511 sends the calculated printing rate to the toner amount management unit 405. The printing rate is, for example, a value obtained by dividing the first toner consumption amount per page calculated by the toner consumption calculation unit 703 by the reference toner consumption amount. For example, if the reference toner consumption amount when a full solid image is formed on an A4-sized transfer material 11 is 300 mg and the first toner consumption amount calculated by the toner consumption calculation unit 703 is 30 mg, the printing rate is 10%.

[0062] (Second toner amount calculation unit) FIG. 10 is an explanatory diagram of the second toner amount calculation unit 505. Here, the second toner consumption amount for black (K) will be described, but the second toner consumption amount for other chromatic colors (yellow, magenta, cyan) is calculated using a similar process. The second toner amount calculation unit 505 calculates the second toner consumption amount based on the line width and number of print pixels contained in the image data for black after halftone processing stored in the image memory of the RAM 403. This image data is data quantized to 1 bit by halftone processing. The second toner amount calculation unit 505 includes a pattern detection unit 1001, a dot counting unit 1002, a calculation unit 1003, and a toner consumption calculation unit 1004.

[0063] The pattern detection unit 1001 analyzes the binary data of the 1-bit image data after halftone processing and detects areas corresponding to predetermined pixel patterns with different line widths (number of consecutive print dots). Specifically, the pattern detection unit 1001 detects multiple pixel patterns in which the number of consecutive print dots is changed within a range of 1 to 8 from the dot arrangement of the target image.

[0064] The dot counting unit 1002 counts the number of image patterns with a predetermined number of consecutive print dots (here, 1 to 8). The number of pixels corresponding to a pixel pattern with a line width of 1 pixel is counted as "Count1." The number of pixels corresponding to a pixel pattern with a line width of 2 pixels is counted as "Count2." Similarly, the number of pixels corresponding to pixel patterns with line widths of 3 to 8 pixels is counted as "Count3" to "Count8." The number of pixels corresponding to a pixel pattern with a line width of 9 pixels or more is counted as "Count*_*."

[0065] In this embodiment, the pattern detection unit 1001 detects a corresponding area based on a predetermined line width in the scanning direction of the laser light in the exposure unit 24. The dot counting unit 1002 counts the number of pixels included in the area.

[0066] The calculation unit 1003 calculates an integrated value by multiplying the number of print pixels counted for each consecutive number of print dots by a correction coefficient corresponding to that classification. The correction coefficient is a numerical value that can be determined in advance based on the results of actual measurements. For example, it is preferable to set the amount of toner consumed per pixel of a solid image without edges to "1," measure the amount of toner consumed per pixel for each pixel pattern with different line widths, and determine the rate of change as the correction coefficient. Figure 11 is an example diagram showing the relationship between the number of consecutive print dots and the correction coefficient.

[0067] The toner consumption calculation unit 1004 calculates a second toner consumption amount based on the integrated value calculated by the calculation unit 1003 and the toner consumption amount per unit pixel. The toner consumption calculation unit 1004 transmits the calculated second toner consumption amount to the toner amount management unit 405.

[0068] If second toner amount calculation unit 505 can acquire data quantized to 1 bit by halftone processing, it may be configured to be provided outside data processing unit 406. For example, second toner amount calculation unit 505 may be provided in printer engine 104.

[0069] (Toner amount management unit) Based on the printing rate acquired from printing rate calculation unit 511, toner amount management unit 405 determines whether to use the first or second toner consumption amount acquired from first toner amount calculation unit 510 or second toner amount calculation unit 505 to calculate the toner consumption amount. Toner amount management unit 405 updates the remaining toner amounts in developing units 26Y, 26M, 26C, and 26K of image forming units 20Y, 20M, 20C, and 20K based on the toner consumption amount for each page. The updated remaining toner amounts are displayed on operation display unit 408 by CPU 401.

[0070] Generally, printed matter with mainly text images has a low print rate, while printed matter with mainly graphic images containing many gradation areas has a medium to high print rate. Therefore, in the case of a low print rate, the remaining toner amount is calculated based on the second toner consumption amount calculated by second toner amount calculation unit 505, which can accurately calculate the toner consumption amount for text areas. In the case of a medium to high print rate, the remaining toner amount is calculated based on the first toner consumption amount calculated by first toner amount calculation unit 510, which can accurately calculate the toner consumption amount for gradation areas.

[0071] 12 is a flowchart showing the remaining toner amount calculation process performed by toner amount management unit 405. Toner amount management unit 405 calculates the remaining toner amounts in developing units 26Y, 26M, 26C, and 26K of image forming units 20Y, 20M, 20C, and 20K each time printer engine 104 outputs an image. Toner amount management unit 405 performs this process under the control of CPU 401.

[0072] The toner amount management unit 405 acquires the in-plane printing rate for each page from the printing rate calculation unit 511 (S1201). The toner amount management unit 405 determines whether the acquired printing rate is equal to or less than a predetermined threshold (S1202). Here, the threshold is, for example, 10%. However, the threshold is not limited to this value and may be any value determined appropriately through experiments. If the printing rate is equal to or less than 10% (S1202: Y), the toner amount management unit 405 determines the toner consumption amount to be the second toner consumption amount acquired from the second toner amount calculation unit 505 (S1203). If the printing rate is greater than 10% (S1202: N), the toner amount management unit 405 determines the toner consumption amount to be the first toner consumption amount acquired from the first toner amount calculation unit 510 (S1204).

[0073] The toner amount management unit 405 stores the toner consumption amount determined in the process of S1203 or S1204 as a β value in the memory 306 of the engine control unit 301 (S1205). In this embodiment, the threshold value of the printing rate is set to 10% as a criterion for determining whether to use the toner consumption amount calculated by the first toner amount calculation unit 510 or the second toner amount calculation unit 505. The printing rate threshold may be set for each of the colors Y, M, C, and K. For example, chromatic colors (Y, M, C) are less frequently used in text images and are often used in graphic images containing many gradation areas. Therefore, the threshold value of the printing rate for black (K) may be set to 10%, and the threshold value of the printing rate for chromatic colors may be set to 5%, prioritizing the calculation accuracy of toner consumption amounts for gradation areas.

[0074] The toner amount management unit 405 updates the remaining toner amount by subtracting the toner consumption amount determined in the processing of S1203 or S1204 from the immediately preceding remaining toner amount (S1206). The toner amount management unit 405 notifies the operation and display unit 408 of the updated remaining toner amount and ends the processing (S1207). The operation and display unit 408 displays the updated remaining toner amount.

[0075] 13 is a flowchart showing the process of updating the remaining toner amount in S1206. The process of updating the remaining toner amount includes the following five steps. S2001: Acquisition process of the reference total soft count value X S2002: Acquisition process of the current total software count value Y of the image forming unit S2003: Update process of correction value α of toner consumption coefficient S2004: Calculation process of predicted value Z of toner usage S2005: Toner remaining amount update process

[0076] The processes of S2001 to S2004 will be described with reference to Figs. 14 to 17. Fig. 14 is a flowchart showing the process of acquiring the reference total soft count value X. Fig. 15 is a flowchart showing the process of acquiring the current total soft count value Y of the developing device 26. Fig. 16 is a flowchart showing the process of updating the correction value α of the toner consumption coefficient. Fig. 17 is a flowchart showing the process of calculating the predicted value Z of the toner usage amount.

[0077] The "processing for obtaining the reference total soft count value X" in step S2001 will be described with reference to Fig. 14. As described above, each of the four image forming units 20Y, 20M, 20C, and 20K of the imaging system 309 of the engine mechanism unit 302 has a nonvolatile memory device.

[0078] The engine control unit 301 starts communication with the memory device of each image forming unit 20Y, 20M, 20C, and 20K (S2101). The engine control unit 301 acquires, from each memory device, a total soft count value X, which serves as a reference and is preset for each type of image forming unit 20Y, 20M, 20C, and 20K (S2102). The total soft count value X is set for each cartridge type, for example, as follows: The cartridge type indicates the type (size, etc.) of the image forming unit 20 (developer 26).

[0079] Cartridge Type A: 500000000 Cartridge Type B: 400000000 Cartridge Type C: 3,000,000,000 Other: 0

[0080] Here, the reference total soft count value X will be described as "500000000." For example, in the case of cartridge type A, "500000000" is stored in memory 306 of engine control unit 301 as the reference total soft count value X. Note that the reference total soft count value X is a soft value converted from the amount of toner that can be used by image forming unit 20 from new until the end of its life, and is not limited to the example number. In other words, the reference total soft count value X is a value indicating the amount of toner (amount of developer) contained in a new image forming unit 20 (developer 26). The number and capacity of cartridge types can be set arbitrarily.

[0081] The "process for obtaining the total soft count value Y of the current image forming unit" in S2002 will be described with reference to Figure 15. The current total soft count value Y is the current integrated value of the toner consumption amount (first toner consumption amount, second toner consumption amount) calculated by the data processing unit 406, and is calculated for each image forming unit 20. The current total soft count value Y of each image forming unit 20 is stored in the memory 306 of the engine control unit 301, and its initial value is "0". The total soft count value Y is a value indicating the accumulated amount of toner consumed.

[0082] The toner amount management unit 405 acquires the β value stored in the memory 306 of the engine control unit 301 (S2201). As described above, the β value is the first toner consumption amount calculated by the first toner amount calculation unit 510 or the second toner consumption amount calculated by the second toner amount calculation unit 505. The toner amount management unit 405 calculates a new total soft count value Y by adding the β value to the current total soft count value Y of the image forming units 20Y, 20M, 20C, and 20K (S2202). The toner amount management unit 405 updates the current total soft count value Y stored in the memory 306 of the engine control unit 301 with the calculated new total soft count value Y (S2203).

[0083] By the processing of S2001 and S2002, the reference total soft count value X and the current total soft count value Y are stored for each image forming unit 20 (each color) in the memory 306 of the engine control unit 301. In other words, the initial value (initial amount) of the amount of toner in the developing unit 26 and the current amount of consumption are stored in the memory 306 of the engine control unit 301.

[0084] The "update process of the correction value α of the toner consumption coefficient" in S2003 will be described with reference to Figure 16. The initial value of the correction value α of the toner consumption coefficient is stored in advance in the memory 306 of the engine control unit 301. The initial value of the correction value α is "1.0". The toner consumption coefficient in this embodiment is the amount of toner consumed per dot. When the image forming unit 20 is replaced, the correction value α of the toner consumption coefficient indicates the toner consumption rate of the replaced image forming unit 20 (the ratio of the amount consumed to the initial amount). The correction value α of the toner consumption coefficient makes it possible to correct for individual differences between image forming units 20 and errors due to the usage environment.

[0085] The toner amount management unit 405 determines whether the image forming unit 20 has been replaced (S2301). If the image forming unit 20 has not been replaced (S2301: N), the toner amount management unit 405 ends the process without updating the correction value α of the toner consumption coefficient (S2306). If the image forming unit 20 has been replaced (S2301: Y), the toner amount management unit 405 acquires the total soft count value X of the replaced image forming unit 20, which serves as the reference value before replacement, from the memory 306 of the engine control unit 301 (S2302). Here, the case where the total soft count value X is "500000000". will be described.

[0086] The toner amount management unit 405 acquires the total soft count value Y at the time of replacement of the image forming unit 20 from the memory 306 of the engine control unit 301 (S2303). Here, a case where the total soft count value Y is "450000000" will be described.

[0087] The toner amount management unit 405 calculates a correction value α of the toner consumption coefficient (S2304). The correction value α is a value obtained by dividing the total soft count number X by the total soft count value Y. That is, the correction value α can be obtained by the following formula. α=X / Y=500000000 / 450000000=1.11

[0088] The toner amount management unit 405 updates the correction value α of the toner consumption coefficient stored in the memory 306 of the engine control unit 301 with the calculated correction value α of the toner consumption coefficient (S2305). Here, the correction value α of the toner consumption coefficient is updated from the initial value "1.0" to "1.11."

[0089] The toner amount management unit 405 may store the correction value α of the toner consumption coefficient without updating it each time the image forming unit 20 is replaced, and may use an average value of multiple correction values ​​α as the correction value α of the toner consumption coefficient. The averaging process is not limited to a simple average, and may use a moving average, exponential average, peak average, Olympic method, or the like. The averaging process makes it possible to converge the prediction error of the remaining toner amount over the long term. α=(α1+α2+α3+…+αn) / n

[0090] The "calculation process of predicted value Z of toner usage amount" in S2004 will be described with reference to Fig. 17. The initial value of predicted value Z of toner usage amount is stored in advance in memory 306 of engine control unit 301. The initial value of predicted value Z of toner usage amount is "0".

[0091] The toner amount management unit 405 acquires the reference total soft count value X, the current total soft count value Y of the cartridge, and the toner consumption coefficient correction value α (S2401, S2402, S2403) from the memory 306 of the engine control unit 301. The toner amount management unit 405 calculates the predicted value Z of the toner usage amount of the image forming unit 20 using the acquired total soft count values ​​X, Y, and correction value α using the following formula (S2404). Z=(Y×α) / X×100

[0092] The toner amount management unit 405 updates the predicted value stored in the memory 306 of the engine control unit 301 with the calculated predicted value Z (S2405). The toner amount management unit 405 updates (calculates) the remaining toner amount with the predicted value Z (S2005).

[0093] The remaining toner amount is updated in the above manner. Fig. 18 is an explanatory diagram of the effect of the above processing executed by the image forming apparatus 102 of this embodiment.

[0094] The horizontal axis is the predicted value of remaining toner. The vertical axis is the actual remaining toner amount [%]. The solid line and black circles show the relationship between the remaining toner amount at the reference value of "100%" predicted with a toner consumption coefficient of "1" and the predicted value. The dotted line and black triangles show the relationship between the remaining toner amount at "90%" when the image forming unit 20 is replaced and the predicted value. The dashed line and black squares show the relationship between the remaining toner amount at "110%" when the image forming unit 20 is replaced and the predicted value.

[0095] Disturbances such as the operating environment and purpose of use cause differences in toner consumption, resulting in a difference in the predicted result compared to the reference value "100%" predicted with a toner consumption coefficient of "1." In this embodiment, by correcting the toner consumption coefficient with the correction value α, it becomes possible to accurately calculate toner consumption regardless of disturbances such as the operating environment and purpose of use. In addition, by averaging the correction value of the toner consumption coefficient each time the image forming unit 20 is replaced, the prediction error in the remaining toner amount can be converged over the long term, making it possible to predict the remaining toner amount with high accuracy.

[0096] (Variation 1) There are variations of the "update process of the toner consumption coefficient correction value α" in S2003. Fig. 19 is a flowchart showing the update process of the toner consumption coefficient correction value α in Variation 1. Here, an upper limit and a lower limit are set for the toner consumption coefficient correction value α.

[0097] The processes of determining whether the image forming unit 20 has been replaced, obtaining the total soft count value Y, and calculating the toner consumption coefficient correction value α are the same as those of S2301 to S2304 in Fig. 16 (S2501 to S2504). Note that if the image forming unit 20 has not been replaced (S2501: N), the toner amount management unit 405 ends the process without updating the toner consumption coefficient correction value α (S2512).

[0098] The toner amount management unit 405 determines the upper limit of the correction value α of the toner consumption coefficient (S2505). Here, the upper limit of the correction value α is set to "1.3" to perform the upper limit determination. If the correction value α calculated in the process of S2504 is "1.3" or greater (S2505: Y), the toner amount management unit 405 sets the toner consumption coefficient correction value α to the upper limit of "1.3" (S2506). The toner amount management unit 405 updates the correction value α stored in the memory 306 of the engine control unit 301 with the set toner consumption coefficient correction value α (S2507). Here, the toner consumption coefficient correction value α is updated from the initial value "1.0" to the upper limit of "1.3".

[0099] If the correction value α calculated in the process of S2504 is less than "1.3" (S2505: N), the toner amount management unit 405 determines the lower limit of the correction value α of the toner consumption coefficient (S2508). Here, the lower limit determination is performed using "0.7" as the lower limit of the correction value α. If the correction value α calculated in the process of S2504 is "0.7" or less (S2508: Y), the toner amount management unit 405 sets the correction value α of the toner consumption coefficient to the lower limit of "0.7" (S2509). The toner amount management unit 405 updates the correction value α stored in the memory 306 of the engine control unit 301 with the set correction value α of the toner consumption coefficient (S2510). Here, the correction value α of the toner consumption coefficient is updated from the initial value "1.0" to the upper limit of "0.7".

[0100] If the correction value α calculated in the process of S2504 is greater than "0.7" (S2508: N), the toner amount management unit 405 sets the correction value α of the toner consumption coefficient to the value calculated in the process of S2504. The toner amount management unit 405 updates the correction value α stored in the memory 306 of the engine control unit 301 with the set correction value α of the toner consumption coefficient (S2511). Here, the correction value α of the toner consumption coefficient is updated to the value calculated in the process of S2504.

[0101] As described above, the correction value α of the toner consumption coefficient is set to the upper limit if it is equal to or greater than the upper limit, and is set to the lower limit if it is equal to or less than the lower limit. Therefore, the correction value α is equal to or less than the upper limit but equal to or greater than the lower limit. Note that the upper and lower limits are merely examples, and other values ​​may also be used. In this type of processing, by setting upper and lower limits for the correction value α of the toner consumption coefficient, the risk of excessive correction can be reduced regardless of disturbances such as the usage environment or usage purpose.

[0102] (Variation 2) As described above, the image forming unit 20 includes the photosensitive drum 22, the charger 23, and the developing unit 26. The image forming unit 20 is replaced not only when toner is consumed in the developing unit 26, but also when the photosensitive drum 22 or the charger 23 has reached the end of its product life. For this reason, if the correction value α is updated when the image forming unit 20 is replaced for reasons other than toner consumption, it may become more difficult to accurately grasp the amount of toner consumed. In Modification 2, this point is taken into consideration when the "update process of the correction value α of the toner consumption coefficient" is performed in S2003.

[0103] 20 is a flowchart showing the process of updating the correction value α of the toner consumption coefficient in Modification 2. Modification 2 is a process modified from Modification 1, in which an upper limit and a lower limit are set for the correction value α of the toner consumption coefficient. However, Modification 2 is also effective in a configuration in which no upper limit or lower limit is set.

[0104] The toner amount management unit 405 determines whether the image forming unit 20 has been replaced (S2601). If the image forming unit 20 has not been replaced (S2601: N), the toner amount management unit 405 ends the process without updating the correction value α of the toner consumption coefficient (S2613). If the image forming unit 20 has been replaced (S2601: Y), the toner amount management unit 405 determines whether the cause of the replacement is the toner end in the developing unit 26 (S2602).

[0105] The toner end determination is made based on the amount of remaining toner calculated in the previous toner remaining amount calculation process, for example. In this case, the toner amount management unit 405 determines that the toner end has occurred when the amount of remaining toner calculated in the previous toner remaining amount calculation process is equal to or less than a predetermined amount.

[0106] If the toner is not out (S2602: N), the toner amount management unit 405 ends the process without updating the toner consumption coefficient correction value α (S2613). If the toner is out (S2602: Y), the toner amount management unit 405 updates the toner consumption coefficient correction value α (S2603 to S2612) by the processes of S2502 to S2511 in FIG.

[0107] In this process, if the image forming unit 20 is replaced for reasons other than toner consumption, the correction value α of the toner correction coefficient is not updated. This is to prevent excessive prediction of the remaining toner amount if the image forming unit 20 is replaced while toner remains. This reduces the risk of excessive correction regardless of disturbances such as the usage environment or usage purpose.

[0108] In the above description, the toner is stored in the image forming unit 20 (developing device 26), and new toner is replenished by replacing the developing device 26. However, the toner may be stored in a storage container separate from the developing device 26, and the storage container may be detachable from the image forming apparatus 102. With this configuration, the toner can be replenished to the developing device 26 by replacing the storage container, and the cost incurred by replacing the developing device 26 can be reduced.

Claims

1. an image forming means for forming an image based on image data on a transfer material using a developer; a data processing means for calculating the amount of developer consumed based on the image data; a management unit that calculates a correction value of the toner consumption amount per dot based on a count value indicating the amount of developer contained in the new image forming unit and an integrated value of the consumption amount, calculates a predicted value of the amount of developer used based on the count value, the integrated value, and the correction value, and calculates the remaining amount of developer based on the predicted value, Image forming device.

2. When the image forming unit is replaced, the management unit calculates the correction value from the count value of the image forming unit before replacement and the integrated value at the time of replacement.

2. The image forming apparatus according to claim 1.

3. The management unit calculates the correction value by dividing the count value by the integrated value.

3. The image forming apparatus according to claim 2.

4. the management means, if the calculated correction value is equal to or greater than an upper limit value, calculates the predicted value using the upper limit value.

4. The image forming apparatus according to claim 3.

5. the management means, if the calculated correction value is equal to or less than a lower limit value, calculates the predicted value using the lower limit value.

4. The image forming apparatus according to claim 3.

6. the management means calculates the predicted value using the upper limit value if the calculated correction value is equal to or greater than an upper limit value, calculates the predicted value using the lower limit value if the calculated correction value is equal to or less than a lower limit value, and calculates the predicted value using the calculated correction value if the calculated correction value is a value between the upper limit value and the lower limit value.

4. The image forming apparatus according to claim 3.

7. the image forming means has components including a developing means for accommodating the developer, the management unit calculates the correction value when the remaining amount of the developer contained in the developing unit falls below a predetermined amount and the image forming unit is replaced.

3. The image forming apparatus according to claim 2.

8. The data processing means an image density correcting means for performing halftone correction processing on the image data and transmitting the image data to the image forming means; and a calculation unit that calculates the consumption amount of the developer based on the image data before the halftone correction process is performed by the image density correction unit.

2. The image forming apparatus according to claim 1.

9. The data processing means an image density correcting means for performing halftone correction processing on the image data and transmitting the image data to the image forming means; and a calculation unit that calculates the consumption amount of the developer based on the image data after the halftone correction process has been performed by the image density correction unit.

2. The image forming apparatus according to claim 1.

10. The data processing means an image density correcting means for performing halftone correction processing on the image data and transmitting the image data to the image forming means; a first calculation means for calculating a first consumption amount of the developer based on the image data before the halftone correction process is performed by the image density correction means; a printing rate calculation means for calculating a printing rate for one page based on the first consumption amount; a second calculation means for calculating a second consumption amount of the developer based on the image data after the halftone correction process has been performed by the image density correction means, the management means calculates the integrated value by setting the consumption amount of developer of the page to the first consumption amount when the printing rate is equal to or less than a threshold value, and by setting the consumption amount of developer of the page to the second consumption amount when the printing rate is greater than the threshold value.

2. The image forming apparatus according to claim 1.

11. An information processing apparatus communicably connected to a printer engine having an image forming means for forming an image based on image data on a transfer material using a developer, a data processing means for calculating the amount of developer consumed based on the image data; a management unit that calculates a correction value of the toner consumption amount per dot based on a count value indicating the amount of developer contained in the new image forming unit and an integrated value of the consumption amount, calculates a predicted value of the amount of developer used based on the count value, the integrated value, and the correction value, and calculates the remaining amount of developer based on the predicted value, Information processing device.

Images