JP2020115181A - Image forming apparatus, waste toner management method, and waste toner management program - Google Patents

Abstract

To accurately predict the time when a free space of a waste toner box is filled with toner regardless of an installation space.SOLUTION: An image forming apparatus comprises: a developing device that forms a toner image made of toner by developing an electrostatic latent image by using a developer consisting of toner and carrier; a photoreceptor drum and an intermediate transfer belt that are an image carrier carrying the toner image formed by the developing device; a drum cleaning blade and a belt cleaning blade that recover, as a waste toner, a toner remaining on the image carrier after the toner image carried by the image carriers is transferred; a waste toner box that stores the waste toner; a waste toner amount prediction unit 55 that predicts the weight of waste toner stored in the waste toner box; and a volume prediction unit 57 that predicts the volume of waste toner stored in the waste toner box based on the atmospheric pressure.SELECTED DRAWING: Figure 4

Description

The present invention relates to an image forming apparatus, a waste toner management method, and a waste toner management program, and more particularly, to an image forming apparatus that forms an image using toner, a waste toner management method executed by the image forming apparatus, and a computer. The present invention relates to a waste toner management program that executes a toner management method.

An image forming apparatus represented by an MFP (Multi Function Peripheral) forms a toner image on a photosensitive drum by agitating a developer including a toner and a carrier by a developing device and applying an electric charge to the toner particles. The toner image formed on the photosensitive drum is transferred to the secondary transfer belt, and further transferred from the secondary transfer belt to a recording medium such as paper. When the toner images formed on the photosensitive drum and the secondary transfer belt are transferred, part of the toner forming the toner image remains without being transferred. The toner remaining on the photosensitive drum or the secondary transfer belt is collected as waste toner and stored in the waste toner box. When the waste toner box is filled with the waste toner, the user replaces the waste toner box with an empty waste toner box. Therefore, it is necessary to notify the user of the replacement time of the waste toner box.

Japanese Unexamined Patent Application Publication No. 2002-214984 describes a technique for determining the replacement time of the waste toner box based on the number of prints, the remaining toner amount, and the like.

On the other hand, it is known that the bulk density of the toner changes depending on the change in atmospheric pressure. For this reason, in the image forming apparatus described in Japanese Patent Application Laid-Open No. 2002-214984, the replacement time is predicted from the amount of toner, and therefore the replacement time cannot be accurately determined depending on the atmospheric pressure of the place where the MFP is arranged. There are problems such as sometimes. For example, when the MFP is placed in a place with a low atmospheric pressure, the waste toner may overflow from the waste toner box, and when the MFP is placed in a place with a high atmospheric pressure, the waste toner box has a free space. Nevertheless, the replacement time may be notified.

JP, 2002-214984, A

One of the objects of the present invention is to provide an image forming apparatus capable of accurately predicting the time when the empty capacity of the waste toner box runs out regardless of the installation location.

Another object of the present invention is to provide a waste toner management method capable of accurately predicting when the empty space of the waste toner box will run out regardless of the installation location of the image forming apparatus.

Still another object of the present invention is to provide a waste toner management program capable of accurately predicting when the empty space of the waste toner box will run out regardless of the installation location of the image forming apparatus.

According to one aspect of the present invention, an image forming apparatus is formed by a developing device that forms a toner image made of toner by developing an electrostatic latent image by using a developer made of toner and a carrier. And an image carrier for carrying the toner image, a collecting means for collecting the toner remaining on the image carrier as a waste toner after the toner image carried by the image carrier is transferred, and a waste toner box for containing the waste toner. A waste toner amount predicting unit that predicts the weight of the waste toner accommodated in the waste toner box, and a volume predicting unit that predicts the volume of the waste toner accommodated in the waste toner box based on the atmospheric pressure.

According to this aspect, the weight of the waste toner stored in the waste toner box is predicted, and the volume of the waste toner stored in the waste toner box is predicted based on the atmospheric pressure. Therefore, it is possible to provide an image forming apparatus capable of accurately predicting when the empty space of the waste toner box will run out regardless of the installation location.

Preferably, it further comprises notifying means for notifying the replacement time of the waste toner box based on the volume predicted by the volume predicting means.

According to this aspect, the replacement time of the waste toner box is notified based on the estimated volume, so that the user can be notified before the waste toner box is filled with the waste toner.

Preferably, the volume prediction unit predicts the volume of the waste toner by using the relationship between the atmospheric pressure and the bulk density of the waste toner.

According to this aspect, the volume of the waste toner can be accurately predicted.

Preferably, the waste toner box further comprises volume detection means for detecting that the waste toner contained in the waste toner box has reached a predetermined volume, and the volume prediction means is configured to detect that the waste toner has reached a predetermined volume by the volume detection means. The volume of the waste toner stored in the waste toner box after the detection is detected is predicted.

According to this aspect, since the volume of the waste toner is predicted after it is detected that the waste toner has reached the predetermined volume, the processing load can be reduced.

Preferably, the volume predicting unit predicts the volume of the toner each time the atmospheric pressure changes.

Preferably, it is possible to cope with fluctuations in atmospheric pressure.

Preferably, a detection unit for detecting the atmospheric pressure is further provided.

Preferably, it further comprises atmospheric pressure information acquisition means for externally acquiring information indicating atmospheric pressure.

Preferably, the developing device discharges a part of the developer as a waste developer to the waste toner box, and the waste toner amount prediction unit predicts the amounts of the waste toner and the waste developer accommodated in the waste toner box, The volume predicting means predicts the volumes of the waste toner and the waste developer accommodated in the waste toner box based on the atmospheric pressure.

According to this aspect, even when the waste developer is stored in the waste toner box, the time when the empty capacity of the waste toner box is exhausted can be accurately predicted.

According to another aspect of the present invention, a waste toner management method is a waste toner management method executed in an image forming apparatus, wherein the image forming apparatus develops an electrostatic latent image to form a toner image including toner. A developing device that forms a toner image, an image carrier that carries the toner image formed by the developing device, and the toner remaining on the image carrier after the toner image carried by the image carrier is transferred is collected as waste toner. A waste toner amount prediction step of predicting the weight of the waste toner accommodated in the waste toner box based on the development by the developing device, and a waste toner box based on the atmospheric pressure. A volume prediction step of predicting the volume of the waste toner accommodated in the toner box.

According to this aspect, it is possible to provide the waste toner management method capable of accurately predicting when the empty space of the waste toner box will run out regardless of the installation location of the image forming apparatus.

According to still another aspect of the present invention, the waste toner management program is a waste toner management program executed by a computer that controls the image forming apparatus, wherein the image forming apparatus develops the electrostatic latent image. A developing device that forms a toner image composed of toner, an image carrier that carries the toner image formed by the developing device, and a toner that remains on the image carrier after the toner image carried by the image carrier are transferred. A waste toner amount predicting step for predicting the weight of the waste toner housed in the waste toner box based on the development by the developing device; and a collecting means for collecting the waste toner and a waste toner box containing the waste toner. The computer is caused to execute a volume prediction step of predicting the volume of the waste toner stored in the waste toner box based on the atmospheric pressure.

According to this aspect, it is possible to provide a waste toner management program capable of accurately predicting when the empty space of the waste toner box will run out regardless of the installation location of the image forming apparatus.

FIG. 3 is a perspective view showing an appearance of an MFP according to one of the embodiments of the present invention. FIG. 3 is a block diagram showing an outline of a hardware configuration of the MFP. FIG. 3 is a schematic cross-sectional view showing the internal configuration of the MFP. 3 is a block diagram illustrating an example of functions of a CPU included in the MFP. FIG. It is a figure which shows an example of a correction table. 6 is a flowchart illustrating an example of the flow of waste toner management processing. It is a figure which shows an example of a consumption rate correction table. FIG. 6 is a diagram showing a relationship between the number of times of image formation and the consumption rate of a waste toner box. FIG. 6 is a diagram showing a relationship between a toner consumption amount and a consumption rate of a waste toner box. It is a figure which shows the relationship between a dot count value and the consumption rate of a waste toner box. It is a block diagram showing an example of a function which a CPU with which a MFP in a 3rd modification has has. 13 is a flowchart showing an example of the flow of waste toner management processing in a third modification. FIG. 6 is a cross-sectional view of the periphery of the developing roller of the developing device as seen from a direction parallel to the central axis of a supply screw included in the developing device. It is the sectional view on the AA line of FIG.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the following description, the same parts are designated by the same reference numerals. Their names and functions are also the same. Therefore, detailed description thereof will not be repeated.

FIG. 1 is a perspective view showing the outer appearance of an MFP according to one of the embodiments of the present invention. FIG. 2 is a block diagram showing an outline of the hardware configuration of the MFP. With reference to FIGS. 1 and 2, an MFP (Multi Function Peripheral) 100 is an example of an image forming apparatus, and conveys a main circuit 110, a document reading unit 130 that reads a document, and a document to the document reading unit 130. It includes an automatic document feeder 120, an image forming section 140 that forms an image on a sheet based on image data, a sheet feeding section 150 that supplies the sheet to the image forming section 140, and an operation panel 160 as a user interface.

The automatic document feeder 120 automatically conveys a plurality of documents set on a document tray one by one to the document reading position of the document reading unit 130, and the document reading unit 130 reads an image formed on the document. The printed document is discharged onto the document output tray.

The image forming unit 140 forms an image on a sheet conveyed by the sheet feeding unit 150 by a known electrophotographic method. In the present embodiment, the image forming unit 140 forms an image on the sheet conveyed by the sheet feeding unit 150 under the image data and the image forming condition corresponding to the medium type of the sheet. The paper on which the image is formed is discharged to the paper discharge tray 159.

The main circuit 110 includes a CPU (central processing unit) 111 that controls the entire MFP 100, a communication interface (I/F) unit 112, a ROM (Read Only Memory) 113, and a RAM (Random Access Memory) 114. A hard disk drive (HDD) 115 as a large capacity storage device, a facsimile unit 116, an atmospheric pressure sensor 117, and an external storage device 118 are included. The CPU 111 is an example of a computer that executes a program. The CPU 111 is connected to the automatic document feeder 120, the document reading unit 130, the image forming unit 140, the paper feeding unit 150, and the operation panel 160 by executing the program, and controls the entire MFP 100.

The ROM 113 stores a program executed by the CPU 111, or data necessary for executing the program. The RAM 114 is used as a work area when the CPU 111 executes the program. Further, the RAM 114 temporarily stores the image data continuously sent from the document reading unit 130.

Operation panel 160 is provided on the top of MFP 100. The operation panel 160 includes a display unit 161 and an operation unit 163. The display unit 161 is, for example, a liquid crystal display device (LCD), and displays an instruction menu for the user, information regarding acquired image data, and the like. Instead of the LCD, an organic EL (electroluminescence) display can be used as long as it is an apparatus that displays an image.

The operation unit 163 includes a touch panel 165 and a hard key unit 167. The touch panel 165 is of a capacitance type. Note that the touch panel 165 is not limited to the electrostatic capacitance method, and other methods such as a resistance film method, a surface acoustic wave method, an infrared method, and an electromagnetic induction method can be used. The hard key unit 167 includes a plurality of hard keys. The hard key is, for example, a contact switch.

Communication I/F unit 112 is an interface for connecting MFP 100 to the network. The communication I/F unit 112 communicates with another computer or a data processing device connected to the network by a communication protocol such as TCP (Transmission Control Protocol) or FTP (File Transfer Protocol). The network to which the communication I/F unit 112 is connected is a local area network (LAN), and the connection form may be wired or wireless. Further, the network is not limited to the LAN, but may be a wide area network (WAN), public switched telephone network (PSTN), the Internet, or the like.

Facsimile unit 116 is connected to the public switched telephone network (PSTN) and transmits facsimile data to PSTN or receives facsimile data from PSTN. The facsimile unit 116 stores the received facsimile data in the HDD 115, converts it into print data that can be printed by the image forming unit 140, and outputs the print data to the image forming unit 140. As a result, the image forming unit 140 forms an image of the facsimile data received by the facsimile unit 116 on a sheet. Further, the facsimile unit 116 converts the data stored in the HDD 115 into facsimile data and transmits the facsimile data to a facsimile device connected to the PSTN.

The atmospheric pressure sensor 117 is arranged near the image forming unit 140. The atmospheric pressure sensor 117 measures the atmospheric pressure and outputs atmospheric pressure information indicating the measured atmospheric pressure to the CPU 111.

The external storage device 118 is controlled by the CPU 111, and a CD-ROM (Compact Disk Read Only Memory) 118A or a semiconductor memory is mounted. In the present embodiment, an example in which the CPU 111 executes a program stored in the ROM 113 will be described. However, the CPU 111 controls the external storage device 118 to read the program to be executed by the CPU 111 from the CD-ROM 118A. Alternatively, the read program may be stored in the RAM 114 and executed.

The CPU 111 controls the image forming unit 140 to form an image of image data on a recording medium such as paper. The image data output by the CPU 111 to the image forming unit 140 includes image data input from the document reading unit 130 and image data such as print data received from the outside.

The recording medium for storing the program to be executed by the CPU 111 is not limited to the CD-ROM 118A, and may be a flexible disk, a cassette tape, an optical disk (MO (Magnetic Optical Disc)/MD (Mini Disc)/DVD (Digital Versatile Disc). )), IC card, optical card, mask ROM, semiconductor memory such as EPROM (Erasable Programmable ROM). Further, the CPU 111 downloads the program from the computer connected to the network and stores the program in the HDD 115, or the computer connected to the network writes the program in the HDD 115 so that the program stored in the HDD 115 is loaded into the RAM 114. Then, it may be executed by the CPU 111. The program mentioned here includes not only a program directly executable by the CPU 111 but also a source program, a compressed program, an encrypted program, and the like.

FIG. 3 is a schematic cross-sectional view showing the internal configuration of the MFP. Referring to FIG. 3, automatic document feeder 120 separates one or more documents placed on a document tray and conveys them one by one to document reading unit 130. The document reading unit 130 exposes the image of the document set on the document glass 11 by the automatic document feeder 120 with the exposure lamp 13 attached to the slider 12 that moves under the document. Reflected light from the document is guided to the lens 16 by the mirror 14 and the two reflection mirrors 15 and 15A, and forms an image on a CCD (Charge Coupled Devices) sensor 18.

The reflected light imaged on the CCD sensor 18 is converted into image data as an electric signal in the CCD sensor 18. The image data is converted into printing data for cyan (C), magenta (M), yellow (Y), and black (K), and is output to the image forming unit 140.

The image forming unit 140 includes yellow, magenta, cyan, and black image forming units 20Y, 20M, 20C, and 20K. Here, “Y”, “M”, “C” and “K” represent yellow, magenta, cyan and black, respectively. An image is formed by driving at least one of the image forming units 20Y, 20M, 20C, and 20K. When all the image forming units 20Y, 20M, 20C and 20K are driven, a full color image is formed. To the image forming units 20Y, 20M, 20C and 20K, yellow, magenta, cyan and black printing data are input, respectively. The image forming units 20Y, 20M, 20C, and 20K differ only in the color of the toner they handle. Therefore, the image forming unit 20Y for forming a yellow image will be described here.

The image forming unit 20Y includes an exposure device 21Y to which yellow printing data is input, a photoconductor drum 23Y that is an image carrier, and a charging roller 22Y that uniformly charges the surface of the photoconductor drum 23Y. A developing device 24Y, a waste toner box 28Y, a primary transfer roller 25Y for transferring the toner image formed on the photosensitive drum 23Y onto an intermediate transfer belt 30 which is an image carrier by the action of an electric field force, A drum cleaning blade 27Y for removing transfer residual toner on the photoconductor drum 23Y, a toner bottle 41Y, and a toner hopper 42Y are provided.

The toner bottle 41Y contains yellow toner. The toner is a non-magnetic material. The toner bottle 41Y rotates using a toner bottle motor as a drive source and discharges toner to the outside. The toner discharged from the toner bottle 41Y is supplied to the toner hopper 42Y. The toner hopper 42Y supplies toner to the developing device 24Y when the remaining amount of the developer contained in the developing device 24Y becomes equal to or less than a predetermined lower limit value. The developer contains a toner and a magnetic carrier.

Around the photosensitive drum 23Y, a charging roller 22Y, an exposure device 21Y, a developing device 24Y, a primary transfer roller 25Y, and a drum cleaning blade 27Y are sequentially arranged along the rotation direction of the photosensitive drum 23Y.

After being charged by the charging roller 22Y, the photoconductor drum 23Y is irradiated with laser light emitted by the exposure device 21Y. The exposure device 21Y exposes an image corresponding portion on the surface of the photoconductor drum 23Y to form an electrostatic latent image. As a result, an electrostatic latent image is formed on the photoconductor drum 23Y. Subsequently, the developing device 24Y develops the electrostatic latent image formed on the photoconductor drum 23Y with charged toner. Specifically, a toner image is formed on the photoconductor drum 23Y by toner being placed on the electrostatic latent image formed on the photoconductor drum 23Y by the action of an electric field force. The toner image formed on the photoconductor drum 23Y is transferred onto the intermediate transfer belt 30 which is an image carrier by the action of an electric field force by the primary transfer roller 25Y. The toner remaining on the photosensitive drum 23Y without being transferred is removed from the photosensitive drum 23Y by the drum cleaning blade 27Y. The toner removed from the photoconductor drum 23Y by the drum cleaning blade 27Y is stored in the waste toner box 28Y as waste toner.

On the other hand, the intermediate transfer belt 30 is suspended by the driving roller 33 and the driven roller 34 so as not to loosen. When the drive roller 33 rotates counterclockwise in FIG. 3, the intermediate transfer belt 30 rotates counterclockwise in the figure at a predetermined speed. The driven roller 34 rotates counterclockwise as the intermediate transfer belt 30 rotates.

As a result, the image forming units 20Y, 20M, 20C, and 20K sequentially transfer the toner images onto the intermediate transfer belt 30. The timing at which each of the image forming units 20Y, 20M, 20C, and 20K transfers the toner image onto the intermediate transfer belt 30 is adjusted by detecting the reference mark attached to the intermediate transfer belt 30. As a result, the yellow, magenta, cyan, and black toner images are superimposed on the intermediate transfer belt 30.

The toner image formed on the intermediate transfer belt 30 is transferred onto the sheet by the action of the electric field force by the secondary transfer roller 26 which is a transfer member. The sheet is conveyed to the nip portion where the intermediate transfer belt 30 conveyed by the timing roller 31 and the secondary transfer roller 26 are in contact with each other. The sheet on which the toner image is transferred is conveyed to the fixing roller 32, and is heated and pressed by the fixing roller 32. As a result, the toner is melted and fixed on the paper. After that, the paper is discharged to the paper discharge tray 39.

A belt cleaning blade 29 is provided upstream of the image forming unit 20Y on the intermediate transfer belt 30. The belt cleaning blade 29 removes the toner remaining on the intermediate transfer belt 30 without being transferred to the sheet. The toner removed from the intermediate transfer belt 30 by the belt cleaning blade 29 is stored as waste toner in any of the waste toner boxes 28Y, 28M, 28C and 28K. In the MFP 100 according to the present embodiment, the waste toner removed from the intermediate transfer belt 30 by the belt cleaning blade 29 is stored in the waste toner box 28Y.

Papers of different sizes are set in the paper feed cassettes 35, 35A, 35B. The sheets accommodated in the paper feed cassettes 35, 35A, and 35B are supplied to the conveyance path by the take-out rollers 36, 36A, and 36B attached to the paper feed cassettes 35, 35A, and 35B, respectively, and are fed by the paper feed roller 37. It is sent to the timing roller 31.

The MFP 100 drives all the image forming units 20Y, 20M, 20C, 20K when forming a full-color image, but when forming a monochrome image, any one of the image forming units 20Y, 20M, 20C, 20K is formed. Drive one. Further, an image can be formed by combining two or more of the image forming units 20Y, 20M, 20C and 20K. Here, an example in which the MFP 100 adopts a tandem system that includes image forming units 20Y, 20M, 20C, and 20K that form toners of four colors on a sheet will be described. A 4-cycle method of sequentially transferring the toner of No. 1 to the paper may be adopted.

FIG. 4 is a block diagram illustrating an example of functions of the CPU included in the MFP. The functions shown in FIG. 4 are realized by the CPU 111 by the CPU 111 included in the MFP 100 executing the waste toner management program stored in the ROM 113, the HDD 115, or the CD-ROM 118A. With reference to FIG. 4, the CPU 111 controls the image forming unit 140, an image formation control unit 51, an atmospheric pressure information acquisition unit 53, a waste toner amount prediction unit 55, a volume prediction unit 57, and a notification unit 59. including.

The image forming control unit 51 controls the image forming unit 140 to form an image on a recording medium. The waste toner amount prediction unit 55 acquires the number of times an image is formed from the image formation control unit 51, and predicts the waste toner amount based on the acquired number of times. The amount of waste toner indicates the weight of waste toner accumulated in the waste toner box 28Y. For example, the amount of waste toner collected when an image is formed on one recording medium is set in advance. The waste toner amount prediction unit 55 obtains the number of times the image forming unit 140 has formed an image, and calculates the waste toner amount by multiplying the number of image formation times by the amount of waste toner per sheet. When a plurality of recording media of different sizes are used, the amount of waste toner is determined for each size of the recording media. Each time the image forming unit 140 forms an image, the amount of waste toner is calculated using the amount of waste toner determined for the size of the recording medium on which the image is formed. The waste toner amount prediction unit 55 stores the calculated waste toner amount and outputs the waste toner amount to the volume prediction unit 57. When the waste toner box 28Y is replaced, the waste toner amount prediction unit 55 resets the waste toner amount, and thereafter, the image forming unit 140 forms an image until the waste toner box 28Y is replaced. Then, the amount of waste toner is calculated.

The atmospheric pressure information acquisition unit 53 acquires atmospheric pressure information output by an atmospheric pressure sensor 117 that measures atmospheric pressure. The atmospheric pressure information is information indicating atmospheric pressure. The atmospheric pressure information acquisition unit 53 outputs the acquired atmospheric pressure information to the volume prediction unit 57. Although an example of acquiring the atmospheric pressure at the present time is shown here, the average atmospheric pressure in the predetermined period may be acquired using the atmospheric pressure information output by the atmospheric pressure sensor 117 in the predetermined period. Further, information indicating the atmospheric pressure in the area where the MFP 100 is installed may be acquired from an external server.

The volume prediction unit 57, based on the waste toner amount input from the waste toner amount prediction unit 55 and the atmospheric pressure information input from the atmospheric pressure information acquisition unit 53, the volume of the waste toner accommodated in the waste toner box 28Y. Predict. Specifically, the volume prediction unit 57 refers to the correction table that defines the relationship between the atmospheric pressure and the bulk density, and obtains the bulk density for the atmospheric pressure determined by the atmospheric pressure information acquired by the atmospheric pressure information acquisition unit 53. The volume predicting unit 57 calculates the volume of the waste toner stored in the waste toner box 28Y from the waste toner amount and the bulk density input from the waste toner amount predicting unit 55.

FIG. 5 is a diagram showing an example of the correction table. With reference to FIG. 5, the correction table defines the relationship between the atmospheric pressure and the correction coefficient. The correction coefficient determines the ratio of the bulk density for each atmospheric pressure to the bulk density determined for the standard atmospheric pressure. Here, the reference atmospheric pressure is 1001 hPa to 1050 hPa, and the correction coefficient for the atmospheric pressure is "1". For example, the correction coefficient is 0.74 when the atmospheric pressure is 800 hPa or less. If the bulk density for an atmospheric pressure of 1001 hPa to 1050 hPa is Db, the bulk density for an atmospheric pressure of 800 hPa or less is 0.74×Db.

Returning to FIG. 4, the volume predicting unit 57 further predicts the replacement time of the waste toner box 28Y. The volume prediction unit 57 calculates the consumption rate of the waste toner box 28Y from the volume of the waste toner stored in the waste toner box 28Y. The consumption rate of the waste toner box 28Y is the ratio of the volume of the waste toner stored in the waste toner box 28Y to the volume of the waste toner box 28Y that can store the waste toner. The volume prediction unit 57 determines the amount of waste toner having the same volume as the empty space of the waste toner box 28Y from the volume of the empty space of the waste toner box 28Y and the bulk density determined based on the atmospheric pressure. The volume of the empty space of the waste toner box 28Y is determined by the waste toner amount predicting unit 55 based on the waste toner amount predicted, and the volume of the waste toner accommodated in the waste toner box 28Y and the waste toner box 28Y are It is calculated from the volume that can accommodate the waste toner. The volume predicting unit 57 calculates the number of times the image forming unit 140 can form an image before the empty space of the waste toner box 28Y is exhausted, as the remaining number. Specifically, the volume prediction unit 57 uses the amount of waste toner having the same volume as the empty space of the waste toner box 28Y and the bulk density corresponding to the atmospheric pressure indicated by the atmospheric pressure information input from the atmospheric pressure information acquisition unit 53. To calculate. Then, the volume prediction unit 57 calculates the remaining number of times from the calculated amount of waste toner and the amount of waste toner generated by image formation per unit number of times by the image forming unit 140. The volume prediction unit 57 outputs a notification instruction to the notification unit 59 when the remaining number of times becomes equal to or less than a predetermined threshold value. The notification instruction includes the remaining number of times.

The notification unit 59 notifies the user of the replacement time of the waste toner box 28Y in response to the notification instruction input from the volume prediction unit 57. For example, the notification unit 59 displays the information for identifying the waste toner box 28Y and the remaining number of times on the display unit 161. Specifically, a message “It is time to replace the yellow waste toner box after XX times of image formation.” is displayed on the display unit 161. “XX” indicates the remaining number of times. Further, instead of the information for identifying the waste toner box 28Y, or separately from it, an illustration showing the position of the waste toner box 28Y may be displayed.

FIG. 6 is a flowchart showing an example of the flow of waste toner management processing. The waste toner management process is a process executed by the CPU 111 by the CPU 111 included in the MFP 100 executing the waste toner management program stored in the ROM 113, the HDD 115, or the CD-ROM 118A. When the MFP 100 forms an image, the CPU 111 manages the waste toner boxes 28Y, 28M, 28C, and 28K by executing the waste toner management process, but manages the waste toner boxes 28Y, 28M, 28C, and 28K. Are the same, so here, a case where the CPU 111 manages the waste toner box 28Y will be described as an example.

Referring to FIG. 6, CPU 111 acquires atmospheric pressure information (step S01) and advances the process to step S02. The atmospheric pressure information output by the atmospheric pressure sensor 117 that measures the atmospheric pressure is acquired. The atmospheric pressure information is information indicating atmospheric pressure. Note that, here, an example of acquiring the atmospheric pressure at the present time is shown, but an average atmospheric pressure in a predetermined period may be acquired. Further, information indicating the atmospheric pressure in the area where the MFP 100 is installed may be acquired from an external server.

In step S02, the correction coefficient of the bulk density is determined based on the atmospheric pressure information, and the process proceeds to step S03. Using the correction table shown in FIG. 5, the correction coefficient determined in the correction table is determined for the atmospheric pressure determined by the atmospheric pressure information acquired in step S01. In step S03, it is determined whether image formation has started. When the CPU 111 receives the image formation instruction, it determines that the image formation has started. CPU 111 waits until image formation starts (NO in step S03), and if image formation has started (YES in step S03), the process proceeds to step S04.

In step S04, the amount of waste toner is predicted, and the process proceeds to step S05. The CPU 111 predicts the amount of waste toner contained in the waste toner box 28Y. The cumulative total of the amount of waste toner after the waste toner box 28Y is replaced is stored in the HDD 115. The CPU 111 adds the amount of waste toner determined for one image formation to the total amount of waste toner stored in the HDD 115, and updates the total amount of waste toner stored in the HDD 115.

In step S05, the remaining number of times image formation is possible is predicted. The consumption rate of the waste toner box 28Y is calculated, and the remaining number is predicted from the consumption rate. Specifically, the CPU 111 determines the bulk density with respect to the atmospheric pressure indicated by the atmospheric pressure information acquired in step S01 by referring to the correction table, and determines the waste toner amount and the bulk density from the predicted waste toner amount and bulk density in step S04. The volume of the waste toner stored in the box 28Y is calculated. Since the volume of the waste toner box 28Y that can store the waste toner is predetermined, the CPU 111 determines that the volume of the waste toner that is stored in the waste toner box 28Y is the volume that can store the waste toner of the waste toner box 28Y. The rate of consumption is calculated as the consumption rate. Then, the CPU 111 obtains the volume of the empty space of the waste toner box 28Y from the consumption rate of the waste toner box 28Y, and discards it from the volume of the empty space and the bulk density corresponding to the atmospheric pressure indicated by the atmospheric pressure information acquired in step S01. The amount of waste toner having the same volume as the empty space of the toner box 28Y is calculated. Then, the CPU 111 calculates the remaining number from the calculated amount of waste toner and the amount of waste toner generated by image formation per unit number of times by the image forming unit 140.

In the next step S06, it is determined whether or not the remaining number of times is less than or equal to threshold value Th. If the remaining number of times is less than or equal to threshold Th, the process proceeds to step S07, but if not, the process returns to step S03.

In step S07, the replacement time of the waste toner box 28Y is notified, and the process ends. Specifically, the CPU 111 displays a message “It is time to replace the yellow waste toner box in XX times of image formation.” on the display unit 161. “XX” indicates the remaining number of times.

<First Modification>
In the above-described embodiment, MFP 100 corrects the bulk density according to the atmospheric pressure using the correction table indicating the relationship between the atmospheric pressure and the bulk density. The MFP 100 in the first modification corrects the consumption rate of the waste toner box 28Y according to the atmospheric pressure. The consumption rate of the waste toner box is the ratio of the waste toner stored in the waste toner box 28Y to the waste toner box 28Y. The consumption rate of the waste toner box 28Y is the ratio of the waste toner volume to the waste toner box 28Y, which is obtained from the amount and bulk density of the waste toner stored in the waste toner box 28Y. In this case, the MFP 100 according to the first modified example uses the consumption rate correction table showing the relationship between the atmospheric pressure and the consumption rate of the waste toner box 28Y. Therefore, it is not necessary to obtain the volume of the waste toner stored in the waste toner box 28Y, and the processing speed is increased.

FIG. 7 is a diagram showing an example of the consumption rate correction table. Referring to FIG. 7, the consumption rate correction table defines the relationship between the atmospheric pressure and the consumption rate correction coefficient. The consumption rate correction coefficient determines the ratio of the consumption rate of the waste toner box 28Y determined for each atmospheric pressure to the consumption rate of the waste toner box 28Y determined for the standard atmospheric pressure. Here, the reference atmospheric pressure is 1001 hPa to 1050 hPa, and the consumption rate correction coefficient for that atmospheric pressure is "1". For example, the consumption rate correction coefficient is 1.25 for an atmospheric pressure of 810 hPa. If the consumption rate for the atmospheric pressure of 1010 hPa is V%, the consumption rate for the atmospheric pressure of 810 hPa or less is 1.25×V%.

By an experiment, the relationship between the number of times of image formation at the standard atmospheric pressure and the consumption rate is obtained and stored in the MFP 100. For example, when the reference atmospheric pressure is 1010 hPa, the volume predicting unit 57 determines the consumption rate of the waste toner box 28Y from the number of image formations by using the relationship between the image formation number and the consumption rate at the reference atmospheric pressure of 1010 hPa. To do. Then, the volume predicting unit 57 determines the consumption rate correction coefficient for the current atmospheric pressure by using the consumption rate correction table, and corrects the consumption rate of the waste toner box 28Y with the consumption rate correction coefficient for the current atmospheric pressure. The consumption rate of the waste toner box 28Y with respect to the atmospheric pressure is predicted.

FIG. 8 is a diagram showing the relationship between the number of times of image formation and the consumption rate of the waste toner box 28Y. Referring to FIG. 8, a graph indicated by a solid line shows a relationship between the number of times of image formation at a standard atmospheric pressure of 1010 hPa and a consumption rate of the waste toner box 28Y, and a graph indicated by a chain line shows a number of times of image formation at a pressure of 820 hPa. The relationship with the consumption rate of the waste toner box 28Y is shown. At the standard atmospheric pressure of 1010 hPa, the consumption rate of the waste toner box 28Y becomes 100% after 40 K times of image formation (K indicates a unit of 1000), whereas at atmospheric pressure of 810 hPa, 32 K times of image formation. Therefore, the consumption rate of the waste toner box 28Y becomes 100%.

<Second Modification>
In the above-described embodiment and the first modification, the amount of waste toner is predicted based on the number of times of image formation, but the amount of waste toner may be predicted from the amount of toner consumption. The amount of toner consumed is the same as the amount of toner supplied to the developing device 24Y. Therefore, the toner consumption amount can be obtained by detecting the toner amount supplied to the developing device 24Y. The relationship between the toner consumption amount and the waste toner amount may be obtained in advance by experiments.

FIG. 9 is a diagram showing the relationship between the toner consumption amount and the consumption rate of the waste toner box 28Y. Referring to FIG. 8, a graph indicated by a solid line shows a relationship between the toner consumption amount at a standard atmospheric pressure of 1010 hPa and a consumption rate of the waste toner box 28Y, and a graph indicated by a dashed line indicates a toner consumption amount at an atmospheric pressure of 820 hPa. The relationship with the consumption rate of the waste toner box 28Y is shown. At a standard atmospheric pressure of 1010 hPa, the consumption amount of toner is 4.0 kg (k indicates a unit of 1000) and the consumption rate of the waste toner box 28Y is 100%. When the consumption amount is 3.2 kg, the consumption rate of the waste toner box 28Y becomes 100%.

Further, the toner consumption amount may be obtained from the image data that is the object of image formation. The number of pixels of the image data is counted, and the amount of toner used per pixel is predetermined. Therefore, the toner consumption amount can be calculated from the dot count value obtained by counting the number of pixels from the image data.

FIG. 10 is a diagram showing the relationship between the dot count value and the consumption rate of the waste toner box 28Y. With reference to FIG. 10, the solid line graph shows the relationship between the dot count value at the standard atmospheric pressure of 1010 hPa and the consumption rate of the waste toner box 28Y, and the dashed line graph shows the dot count value at the atmospheric pressure of 820 hPa. The relationship with the consumption rate of the waste toner box 28Y is shown. At the standard atmospheric pressure of 1010 hPa, the dot count value is 4.0E+13 and the consumption rate of the waste toner box 28Y is 100%, whereas at the atmospheric pressure of 810 hPa, the dot count value is 3.2E+13 and the waste toner box 28Y is Consumption rate of 100%.

<Third Modification>
The MFP 100 according to the third modified example is provided with an optical sensor that detects that a predetermined amount of waste toner is accumulated in the waste toner box 28Y. Specifically, the waste toner box 28Y has a window portion that transmits light on its side surface, and the window portion is provided with an optical sensor. The optical sensor includes a light emitting unit that emits light and a light receiving unit that receives the light. The window is provided at a predetermined height from the bottom surface of the waste toner box 28Y. When the waste toner is accumulated in the waste toner box 28Y up to the height of the window, the light emitted from the light emitting portion of the optical sensor is blocked by the waste toner and cannot be received by the light receiving portion.

FIG. 11 is a block diagram showing an example of functions of the CPU included in the MFP according to the third modification. The function shown in FIG. 11 is different from the function shown in FIG. 4 in that the volume predictor 57 is changed to a volume predictor 57A and a volume detector 61 is added. Since other functions are the same as those shown in FIG. 4, description thereof will not be repeated here.

The volume detection unit 61 detects that the waste toner accumulated in the waste toner box 28Y has a predetermined volume. The volume detection unit 61 determines that the waste toner has accumulated up to the window in the waste toner box 28Y when the light emitted from the light emitting unit of the optical sensor cannot be received by the light receiving unit. The volume detection unit 61 outputs a detection instruction to the volume prediction unit 57A when the light emitted from the light emitting unit of the optical sensor cannot be received by the light receiving unit.

The volume predicting unit 57A predicts the volume of the waste toner accommodated in the waste toner box 28Y after the detection instruction is input from the volume detecting unit 61. The volume predicting unit 57A sets the volume of the waste toner stored in the waste toner box 28Y to a predetermined value when the detection instruction is input from the volume detecting unit 61. The volume prediction unit 57A refers to the correction table that defines the relationship between the atmospheric pressure and the bulk density, and obtains the bulk density for the atmospheric pressure determined by the atmospheric pressure information acquired by the atmospheric pressure information acquisition unit 53. The volume predicting unit 57A uses the waste toner amount and bulk density input from the waste toner amount predicting unit 55 after the detection instruction is input from the volume detecting unit 61, and then discards the waste toner after the detection instruction is input from the volume detecting unit 61. The volume of the waste toner contained in the toner box 28Y is calculated. The volume prediction section 57A receives the detection instruction from the volume detection section 61, and then inputs the detection instruction from the volume detection section 61 to the waste toner box accommodated in the waste toner box 28Y. The volume of the waste toner accommodated in the waste toner box 28Y is determined by adding the volumes of the waste toner accommodated in 28Y.

The volume prediction section 57A further predicts the replacement time of the waste toner box 28Y. The volume prediction unit 57A calculates the consumption rate of the waste toner box 28Y from the volume of the waste toner stored in the waste toner box 28Y. The volume prediction unit 57A determines the amount of waste toner having the same volume as the empty space of the waste toner box 28Y from the volume of the empty space of the waste toner box 28Y and the bulk density determined based on the atmospheric pressure. Further, the volume prediction unit 57A calculates the amount of waste toner having the same volume as the empty space of the waste toner box 28Y using the bulk density corresponding to the atmospheric pressure indicated by the atmospheric pressure information input from the atmospheric pressure information acquisition unit 53. .. Then, the volume prediction unit 57A calculates the remaining number of times from the calculated amount of waste toner and the amount of waste toner generated by image formation per unit number of times by the image forming unit 140. The volume predicting unit 57A outputs a notification instruction to the notifying unit 59 when the remaining number of times is equal to or less than a predetermined threshold value.

FIG. 12 is a flowchart showing an example of the flow of waste toner management processing in the third modification. Referring to FIG. 12, the difference from the waste toner management processing shown in FIG. 6 is that step S01A is added before step S01. The other processing is the same as the processing shown in FIG. 6, and therefore the description will not be repeated here.

In step S01A, it is determined whether the optical sensor OFF is detected. Specifically, in the optical sensor provided on the side surface of the waste toner box 28Y, when the light receiving unit no longer receives the light emitted by the light emitting unit, the optical sensor is detected to be OFF. The process waits until the optical sensor OFF is detected (NO in step S01A), and if the optical sensor OFF is detected (YES in step S01A), the process proceeds to step S01.

<Fourth Modification>
The MFP 100 in the fourth modified example adopts a trickle method in which the developer accommodated in the developing device 24Y is gradually discarded and a new developer is replenished. Therefore, the toner bottle 41Y contains the yellow developer. The developer contains a non-magnetic toner and a magnetic carrier. The toner bottle 41Y rotates using a toner bottle motor as a drive source and discharges the developer to the outside. The developer discharged from the toner bottle 41Y is supplied to the toner hopper 42Y. The toner hopper 42Y supplies the developer to the developing device 24Y when the remaining amount of the developer contained in the developing device 24Y becomes equal to or lower than a predetermined lower limit value. The waste toner box 28Y stores, as waste toner, toner that remains on the photosensitive drum 23Y, which is an image carrier, and the intermediate transfer belt 30, and also stores the developer discharged from the developing device 24Y as waste developer.

FIG. 13 is a cross-sectional view of the periphery of the developing roller of the developing device as seen from a direction parallel to the central axis of the supply screw of the developing device. FIG. 14 is a cross-sectional view taken along the line AA of FIG. The developing device 24Y forms a toner image on the photoconductor drum 23Y using a developer including a carrier and toner. The developing device 24Y is supplied with the developer from the toner hopper 42Y and discharges the excess developer. The developing device 24Y includes a case 200Y, a second screw 203Y, a first screw 201Y, and a developing roller 221Y.

A sensor that detects the amount of the developer in the case 200Y is attached to the case 200Y. When the amount of the developer detected by the sensor is smaller than the predetermined value, the developer is supplied from the toner hopper 42Y to the case 200Y.

The case 200Y is a housing that houses the developer, the second screw 203Y, the first screw 201Y, and the developing roller 221Y. The developing roller 221Y, the first screw 201Y, and the second screw 203Y are provided in parallel in the case 200Y. In the following, the direction in which the developing roller 221Y, the first screw 201Y, and the second screw 203Y extend is defined as the X-axis direction. Further, a direction orthogonal to the X-axis direction and the vertical direction is defined as the Y-axis direction.

The case 200Y is a container extending in the X-axis direction and has two spaces, a first circulation tank Sp1 and a second circulation tank Sp2, which are separated by a partition wall 205 extending in the X-axis direction. An opening 207 is provided at the end of the partition wall 205 on the negative side in the X-axis direction, and an opening 209 is provided near the end on the positive side in the X-axis direction.

The developing roller 221Y is in the form of a sleeve having a built-in magnet having a plurality of magnetic poles, and is rotationally driven while maintaining a slight distance from the photosensitive drum 23Y. The developing roller 221Y is provided inside the first circulation tank Sp1 so as to face the first screw 201Y. Further, the developing roller 221Y is exposed from the case 200Y and faces the photoconductor drum 23Y. The developing roller 221Y has a built-in magnet, and attracts a magnetic carrier together with a non-magnetic toner by a magnetic force to carry the developer conveyed by the first screw 201Y.

The developing roller 221Y applies toner to the photoconductor drum 23Y to develop the electrostatic latent image. Specifically, a developing bias is applied to the developing roller 221Y. As a result, the potential of the peripheral surface of the developing roller 221Y is lower than the potential (approximately 0V) of the portion of the peripheral surface of the photoconductor drum 23Y where the laser beam is irradiated by the exposure device 21Y, and the peripheral potential of the photoconductor drum 23Y is small. It becomes higher than the potential of the portion of the surface not irradiated with the laser light. Since the toner in the developer carried by the developing roller 221Y is negatively charged, it adheres to the portion of the peripheral surface of the photosensitive drum 23Y irradiated with the laser light. As a result, a toner image is formed on the peripheral surface of the photoconductor drum 23Y by the negatively charged toner.

The first circulation tank Sp1 is a space for supplying the developer to the developing roller 221Y and collecting the remaining developer after the development. At the end of the first circulation tank Sp1 on the positive side in the X-axis direction, a discharge port 211Y for discharging the remaining developer after the development is arranged. The discharge port 211Y communicates with the waste toner box 28Y.

The second circulation tank Sp2 is a space adjacent to the first circulation tank Sp1 in parallel with the partition wall 205, and is a space for stirring and mixing the developer. The developer supplied from the toner hopper 42Y is replenished to the second circulation tank Sp2 from the replenishment port 206Y provided in the second circulation tank Sp2.

The first circulation tank Sp1 is provided with a first screw 201Y, and the second circulation tank Sp2 is provided with a second screw 203Y. Each of the first screw 201Y and the second screw 203Y has a shape in which a spiral blade is provided on the outer peripheral surface of a cylindrical rotating shaft extending in the X-axis direction, and conveys the developer by rotating. ..

The first screw 201Y is divided into three parts. The first screw 201Y is a portion from the end portion on the negative side in the X-axis direction to the end portion on the positive side, and from the midpoint c1 of the opening 209 in the X-axis direction to the negative side in the X-axis direction. 213a is provided with a first blade W1 for transporting the developer toward the positive side in the X-axis direction. Further, in the first screw 201Y, no blade is provided in the portion 213b near the opening 209 adjacent to the portion 213a provided with the first blade W1. Further, in the first screw 201Y, the second blade W2 is provided on the portion 213c on the positive side in the X-axis direction adjacent to the portion 213b. The second wing W2 is reversely wound with the first wing W1.

Here, the range of the opening 209 is from the position overlapping the end of the portion 213a provided with the first wing W1 on the positive side in the X-axis direction to the X-axis direction of the portion 213c provided with the second wing W2. Extends to the negative end of. In the first screw 201Y, the screw diameter of the portion 213a provided with the first blade W1 and the screw diameter of the portion 213c provided with the second blade W2 are the same, and the pitch P1 of the first blade W1 is It is larger than the pitch P2 of the wing W2. Further, the length of the portion 213b where the wing is not provided in the X-axis direction is smaller than the pitch P1 of the first wing W1 and larger than half the pitch P2 of the second wing W2.

The second screw 203Y is provided in the second circulation tank Sp2. Further, the second screw 203Y is provided with wings over the entire area thereof, and is provided with a developer in the second circulation tank Sp2 and a developer supplied from a supply port 206Y provided in the second circulation tank Sp2. Responsible for stirring and carrying. The second screw 203Y conveys the developer to the negative side in the X-axis direction.

In the developing device 24Y, the developer transported by the first screw 201Y to the positive side in the X-axis direction in the first circulation tank Sp1 enters the second circulation tank Sp2 through the opening 209. The developer that has entered the second circulation tank Sp2 is conveyed to the negative side in the X-axis direction by the second screw 203Y, and returns from the opening 207 to the first circulation tank Sp1. As described above, the developer circulates in the section from the opening 207 to the opening 209 in the first circulation tank Sp1 and the section from the opening 209 to the opening 207 in the second circulation tank Sp2.

When the pressure of the developer conveyed by the first wing W1 in the first circulation tank Sp1 exceeds a predetermined value, a part of the developer conveyed in the first circulation tank Sp1 is discharged from the opening 209. It does not enter the second circulation tank Sp2, but goes toward the end of the first circulation tank Sp1 on the positive side in the X-axis direction, beyond the second blade W2 of the first screw 201Y. Then, the developer directed to the end portion of the first circulation tank Sp1 on the positive side in the X-axis direction is discharged from the discharge port 211Y to the waste toner box 28Y. The portion of the first circulation tank Sp1 provided with the discharge port 211Y, that is, the region of the first circulation tank Sp1 on the positive side in the X-axis direction with respect to the second blade W2 of the first screw 201Y is the second circulation tank Sp2. Does not communicate with the Y-axis direction.

In the MFP 100 according to the fourth modification, the developer including the toner and the carrier is discharged from the developing device 24Y to the waste toner box 28Y as the waste developer. The CPU 111 included in the MFP 100 according to the fourth modified example has the same function as that shown in FIG. 4, but the waste toner amount prediction unit 55 predicts the weight of the waste toner and the weight of the waste developer. .. Further, the volume prediction unit 57 predicts the volume of the waste toner and the volume of the waste developer.

The MFP 100 in the fourth modified example may be combined with the second modified example and the third modified example. When the MFP 100 in the fourth modified example is combined with the third modified example, the CPU 111 included in the MFP 100 in the fourth modified example has the same function as that shown in FIG. In this case, the volume detector 61 detects that the waste toner and the waste developer accumulated in the waste toner box 28Y have a predetermined volume. The volume detecting unit 61 determines that the waste toner and the waste developer have accumulated in the waste toner box 28Y up to the window when the light emitted from the light emitting unit of the optical sensor cannot be received by the light receiving unit. The volume detection unit 61 outputs a detection instruction to the volume prediction unit 57A when the light emitted from the light emitting unit of the optical sensor cannot be received by the light receiving unit.

As described above, the MFP 100 according to the present embodiment functions as an image forming apparatus, predicts the weight of the waste toner stored in the waste toner box 28Y, and determines the weight of the waste toner stored in the waste toner box based on the atmospheric pressure. Predict volume. Therefore, it is possible to accurately predict the time when the empty capacity of the waste toner box will run out regardless of the place where the MFP 100 is installed. In particular, when the MFP 100 is set in a region where the atmospheric pressure is lower than the standard atmospheric pressure of 1010 hPa, the waste toner overflows from the waste toner box 28Y, or the waste toner box 28Y cannot store the waste toner and the MFP 100 does not operate. Can be prevented. On the contrary, when the MFP 100 is set in an area where the atmospheric pressure is lower than the standard atmospheric pressure of 1010 hPa, the user is notified of the replacement time or the MFP 100 does not operate even though the waste toner box 28Y has a free space. Can be prevented.

Further, since the MFP 100 notifies the user of the replacement time of the waste toner box 28Y based on the predicted volume, the user can be notified before the waste toner box 28 is filled with the waste toner and the free space is exhausted.

Further, since the MFP 100 predicts the volume of the waste toner by using the correction table that defines the relationship between the atmospheric pressure and the bulk density of the waste toner, it is possible to accurately predict the volume of the waste toner.

Further, the MFP 100 predicts the volume of the waste toner stored in the waste toner box after it is detected that the waste toner stored in the waste toner box 28Y has reached a predetermined volume. Therefore, the load of the processing executed by MFP 100 can be reduced.

The MFP 100 according to the fourth modification adopts a trickle system in which the developer stored in the developing device 24Y is gradually discarded and a new developer is replenished, and the waste toner and the waste developer stored in the waste toner box 28Y are removed. The amount is predicted, and the volumes of the waste toner and the waste developer accommodated in the waste toner box 28Y are predicted based on the atmospheric pressure. Therefore, even when the trickle method is adopted, it is possible to accurately predict when the waste toner box will run out of free space.

The MFP 100 according to the present embodiment includes waste toner boxes 28Y, 28M, 28C, and 28K corresponding to the developing devices 24Y, 24M, 24C, and 24K, respectively. One waste toner box may be provided.

The embodiments disclosed this time are to be considered as illustrative in all points and not restrictive. The scope of the present invention is shown not by the above description but by the claims, and is intended to include meanings equivalent to the claims and all modifications within the scope.

<Appendix>
(1) The image forming apparatus according to claim 2, wherein the relationship between the atmospheric pressure and the bulk density of the waste toner is such that the lower the atmospheric pressure, the lower the bulk density.
(2) The image forming apparatus according to claim 5, wherein the volume predicting unit predicts the volume of the toner by using an average of atmospheric pressure detected by the detecting unit in a predetermined period.

100 MFP, 111 CPU, 51 image formation control unit, 53 atmospheric pressure information acquisition unit, 55 waste toner amount prediction unit, 57 volume prediction unit, 57A volume prediction unit, 59 notification unit, 61 volume detection unit, 20Y, 20M, 20C, 20K image forming unit, 21Y, 21M, 21C, 21K exposure device, 22Y, 22M, 22C, 22K charging roller, 23Y, 23M, 23C, 23K photosensitive drum, 24Y, 24M, 24C, 24K developing device, 25Y, 25M, 25C, 25K Primary transfer roller, 26 Secondary transfer roller, 27Y, 27M, 27C, 27K Drum cleaning blade, 28Y, 28M, 28C, 28K Waste toner box, 29 Belt cleaning blade, 30 Intermediate transfer belt, 31 Timing roller, 32 fixing roller, 33 driving roller, 34 driven roller, 35, 35A, 35B paper feeding cassette, 37 paper feeding roller, 39 paper ejection tray, 41Y, 41M, 41C, 41K toner bottle, 42Y, 42M, 42C, 42K toner hopper , 200Y case, Sp1 first circulation tank, Sp2 second circulation tank, 201Y first screw, 203Y second screw, W1 and W2 blades, 205 partition wall, 206Y supply port, 207,209 opening, 211Y discharge port, 221Y development roller.

Claims (10)

A developing device for forming a toner image composed of toner by developing an electrostatic latent image using a developer composed of toner and carrier;
An image carrier for carrying the toner image formed by the developing device;
Collection means for collecting, as waste toner, the toner remaining on the image carrier after the toner image carried by the image carrier is transferred,
A waste toner box containing the waste toner;
Waste toner amount predicting means for predicting the weight of the waste toner stored in the waste toner box,
An image forming apparatus including: a volume prediction unit that predicts a volume of the waste toner stored in the waste toner box based on atmospheric pressure. The image forming apparatus according to claim 1, further comprising notifying means for notifying a replacement time of the waste toner box based on the volume predicted by the volume predicting means. The image forming apparatus according to claim 1, wherein the volume prediction unit predicts the volume of the waste toner by using a relationship between atmospheric pressure and the bulk density of the waste toner. Further comprising volume detection means for detecting that the waste toner contained in the waste toner box has reached a predetermined volume,
4. The volume predicting means predicts the volume of the waste toner stored in the waste toner box after the volume detecting means detects that the waste toner has reached a predetermined volume. The image forming apparatus according to any one of claims. The image forming apparatus according to claim 1, wherein the volume predicting unit predicts the volume of the toner each time the atmospheric pressure changes. The image forming apparatus according to claim 1, further comprising a detection unit that detects atmospheric pressure. The image forming apparatus according to claim 1, further comprising atmospheric pressure information acquisition means for externally acquiring information indicating atmospheric pressure. The developing device discharges a part of the developer to the waste toner box as a waste developer,
The waste toner amount prediction means predicts the amounts of the waste toner and the waste developer accommodated in the waste toner box,
The image forming apparatus according to claim 1, wherein the volume prediction unit predicts the volumes of the waste toner and the waste developer accommodated in the waste toner box based on the atmospheric pressure. A waste toner management method executed by an image forming apparatus, comprising:
The image forming apparatus includes a developing device that forms a toner image made of toner by developing an electrostatic latent image,
An image carrier for carrying the toner image formed by the developing device;
Collection means for collecting, as waste toner, the toner remaining on the image carrier after the toner image carried by the image carrier is transferred,
A waste toner box for storing the waste toner;
A waste toner amount predicting step of predicting the weight of the waste toner accommodated in the waste toner box based on the development by the developing device;
And a volume prediction step of predicting a volume of the waste toner accommodated in the waste toner box based on atmospheric pressure. A waste toner management program executed by a computer that controls an image forming apparatus,
The image forming apparatus includes a developing device that forms a toner image made of toner by developing an electrostatic latent image,
An image carrier for carrying the toner image formed by the developing device;
Collection means for collecting, as waste toner, the toner remaining on the image carrier after the toner image carried by the image carrier is transferred,
A waste toner box for storing the waste toner;
A waste toner amount predicting step of predicting the weight of the waste toner accommodated in the waste toner box based on the development by the developing device;
A waste toner management program for causing the computer to perform a volume prediction step of predicting a volume of the waste toner stored in the waste toner box based on atmospheric pressure.

Images