Image forming system

Abstract

To correctly notify a user of a consumable item to be replaced when the user desires to replace a cartridge, to prevent the user from replacing a cartridge that does not need to be replaced, and thereby improve usability during replacement.SOLUTION: When a torque detection unit 208 does not detect an abnormality in a first period until an acquisition value reaches a threshold, a control unit 61 does not permit switching from a regulation state to a non-regulation state, when the torque detection unit 208 detects an abnormality in a cartridge 12, permits the switching from the regulation state to the non-regulation state, and in a second period after the acquisition value reaches the threshold, permits the switching from the regulation state to the non-regulation state (S201-S205).SELECTED DRAWING: Figure 7

Description

[Technical Field]

[0001] The present invention , painting The present invention relates to an image forming system, for example, an electrophotographic or electrostatic image forming apparatus such as a copying machine or a printer. [Background technology]

[0002] Conventional color image forming apparatuses use multiple optical devices to independently scan multiple photosensitive drums with light beams, forming toner images of different colors using multiple developing devices. The toner images of different colors formed on the photosensitive drums are then superimposed on an intermediate transfer belt and finally transferred to paper, or the toner images of different colors are superimposed and transferred to a transfer material on the belt. Conventionally, color images are formed using this tandem system. In some tandem-type color image forming apparatuses, the photosensitive drums and toner image forming devices, such as developing devices, in each image forming unit are integrated into a cartridge to form a process cartridge. The cartridge-type process cartridges are detachably arranged in a row in the image forming apparatus main body. In image forming apparatuses equipped with such process cartridges, for example, when the developer runs out, the user may replace the process cartridge themselves, without the need for a service technician. This allows for image formation to resume and also allows for the simultaneous replacement of other consumables, such as the photosensitive drums, improving maintainability.

[0003] Meanwhile, various environmentally friendly technologies have been proposed for image forming apparatuses to ensure that process cartridges, including toner containers, are used to the fullest extent possible. For example, Patent Document 1 discloses a system in which a stopper of a process cartridge is disabled (released) only when it is detected that the process cartridge needs to be replaced, allowing the process cartridge to be attached and detached. Patent Document 2 also discloses a system in which a locking device for locking a toner container cover and a device for detecting whether the toner container is out of toner are used. With this configuration, when the toner container is out of toner, the toner container cover is unlocked by a user's operation, allowing the toner container to be replaced. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2005-091462 [Patent Document 2] Japanese Patent Application Laid-Open No. 2011-008142 Summary of the Invention [Problem to be solved by the invention]

[0005] In this way, in consideration of the environment, a locking mechanism is provided to prohibit cartridge replacement until the toner in the cartridge is used up, and the locking mechanism is locked so that the user cannot easily release it. However, with this configuration, the following problems may occur.

[0006] Depending on the user's environment and conditions, it is possible that an image defect caused by a cartridge may occur before the cartridge can be replaced. In such a case, even if the user wishes to replace the cartridge, the cartridge cannot be replaced until the cartridge replacement timing determined by the device. Furthermore, even if the user is able to replace the cartridge when an image defect occurs, there is a risk that the user may mistakenly replace a cartridge that is not causing the image defect, resulting in an unnecessary replacement.

[0007] The present invention has been made under such circumstances, and aims to improve usability at the time of replacement by correctly notifying a user of consumables to be replaced when the user desires to replace a cartridge, thereby preventing the user from accidentally replacing a cartridge that does not need to be replaced. [Means for solving the problem]

[0008] In order to solve the above-mentioned problems, the present invention has the following configuration.

[0009] (1) A plurality of cartridges, each having a rotatable roller for carrying toner and a container for containing toner to be supplied to the roller; Multiple An image forming system including an image forming apparatus having an apparatus main body into which a cartridge can be attached and detached in the direction of the rotation axis of the roller, a server connected to the image forming apparatus via a network, and an information processing apparatus connected to the server via the network, wherein the apparatus main body has a switching mechanism capable of switching between a restricted state in which removal of the cartridge from the apparatus main body is restricted and a non-restricted state in which removal is not restricted, a detection unit that detects an abnormality in the cartridge, and a control unit that controls the switching mechanism; an image forming unit that forms a test image, the test image including a first region and a second region, the first region being a region where a reference image in which a plurality of reference color images are formed on a recording material is formed, and the second region being a region where a determination image in which a plurality of color images are superimposed on the recording material is formed; and a reading unit that reads the reference image and the determination image formed on the recording material by the image forming unit;the control unit controls the switching mechanism to switch the cartridge into the regulated state when the amount of toner in the storage unit is greater than a predetermined amount, and into the non-regulated state when the amount of toner in the storage unit is less than the predetermined amount, and controls the switching mechanism to switch the cartridge into the non-regulated state when the server determines that the detection result of the detection unit is abnormal even when the amount of toner in the storage unit is greater than the predetermined amount, The server detects an abnormality in the cartridge based on the detection result of the detection unit when an amount of change in density between the reference image and the determination image based on information read by the reading unit from both the reference image and the determination image is greater than a first threshold value, The image forming system is characterized in that the result of the determination by the server is transmitted to the information processing device and the control unit. [Effects of the Invention]

[0012] According to the present invention, when a user desires to replace a cartridge, the user is correctly notified of the consumables that need to be replaced, preventing the user from accidentally replacing a cartridge that does not need to be replaced, thereby improving usability during replacement. [Brief explanation of the drawings]

[0013] [Figure 1] Schematic cross-sectional view of an image forming apparatus according to a first embodiment [Figure 2] 1 is a perspective view of a door according to a first embodiment of the present invention; [Figure 3] FIG. 1 is a diagram showing a locking mechanism of the cartridge according to the first embodiment. [Figure 4] Block diagram of the control configuration of the first embodiment [Figure 5] 1 is a flowchart showing control when the unlocking criteria is reached in the first embodiment. [Figure 6] FIG. 10 is a diagram showing a drive torque determination in the first embodiment. [Figure 7] Flowchart showing drive torque determination in the first embodiment [Figure 8] FIG. 10 is a perspective view of an image forming apparatus showing a lock mechanism having another configuration according to the first embodiment; [Figure 9] Block diagram of the control configuration of the second embodiment [Figure 10] Schematic cross-sectional view of an image forming apparatus according to a second embodiment of the present invention. [Figure 11] Flowchart showing the process of the second embodiment [Figure 12]Flowchart showing image diagnosis in Example 2 [Figure 13] 10A and 10B show diagnostic images and detection images of Example 2. [Figure 14] FIG. 10 shows a network configuration of a third embodiment. [Figure 15] Block diagram of the control configuration of the third embodiment [Figure 16] Flowchart showing the process of the third embodiment [Figure 17] Flowchart for explaining permission and prohibition of switching in the first to third embodiments DETAILED DESCRIPTION OF THE INVENTION

[0014] The image forming apparatus and image forming system according to the present invention will be described in more detail below with reference to the drawings. Note that the following examples do not limit the scope of the invention. While the examples describe multiple features, not all of these features are necessarily essential to the invention, and multiple features may be combined in any desired manner. Furthermore, in the accompanying drawings, identical or similar components are designated by the same reference numerals, and redundant explanations will be omitted. [Example]

[0015] [Image forming equipment] FIG. 1 is a diagram showing the overall configuration of a tandem color image forming apparatus 1 according to a first embodiment. The tandem color image forming apparatus 1 is configured to output full-color images by overlaying toner, which is a developer, of four colors: yellow (Y), magenta (M), cyan (C), and black (K). The subscripts Y, M, C, and K in the reference numerals represent the respective colors. Note that the subscripts Y, M, C, and K are omitted except when describing a specific color. To form images of each color, a laser scanner 11 serving as an exposure means and a cartridge 12 are provided. The cartridge 12 is composed of a photosensitive drum 13 that rotates in the direction indicated by the arrow in the figure, a drum cleaner 14 provided in contact with the photosensitive drum 13, a charging roller 15, a developing roller 16 (a rotating body), and a toner container 6 (a container) that contains toner to be supplied to the developing roller 16. An intermediate transfer belt 17 is provided in contact with the photosensitive drum 13 of each color, and a primary transfer roller 18 is provided facing the intermediate transfer belt 17. Furthermore, paper 21, which is a recording material, is stored in a cassette 22. A paper feed roller 25, a transport roller 26, and a registration roller (hereinafter referred to as a registration roller) 27 are provided on the transport path of the paper 21. A registration sensor (hereinafter referred to as a registration sensor) 28 is provided near the downstream side of the registration roller 27 in the transport direction of the paper 21. A secondary transfer roller 29 is provided in contact with the intermediate transfer belt 17, and a fuser 30 and a discharge roller 59 are provided downstream of the secondary transfer roller 29 in the transport direction. A discharge section paper presence sensor 53 is provided near the discharge roller 59. A cleaning unit 20 including a cleaning blade 19 is arranged on the intermediate transfer belt 17.

[0016] Next, the electrophotographic process will be described. First, the surface of the photosensitive drum 13 is uniformly charged by the charging roller 15. Next, the laser scanner 11 irradiates the surface of the photosensitive drum 13 with laser light modulated according to image data, and the charged charge is removed from the area irradiated with the laser light. This forms an electrostatic latent image on the surface of the photosensitive drum 13. The developing roller 16 attaches charged toner to the electrostatic latent image, forming a toner image of each color on the surface of the photosensitive drum 13. The toner images formed on the surface of each photosensitive drum 13 are then transferred by the primary transfer roller 18 to the intermediate transfer belt 17 so that they are sequentially superimposed on top of each other (primary transfer).

[0017] Meanwhile, paper 21 in cassette 22 is transported by paper feed rollers 25, and transport rollers 26 transport the paper 21 to registration rollers 27. Next, the toner image on intermediate transfer belt 17 is transferred by secondary transfer rollers 29 onto paper 21 transported by registration rollers 27 (secondary transfer). The unfixed toner image on paper 21 is fixed by fuser 30, and then paper 21 is discharged outside image forming apparatus 1 by discharge rollers 59. A discharge section paper presence / absence sensor 53 is provided near discharge rollers 59 to detect the presence or absence of paper 21 discharged from discharge rollers 59. After transfer, intermediate transfer belt 17 is cleaned by cleaning blade 19.

[0018] The image forming apparatus 1 also includes a control board 60, a toner remaining amount detection unit 62, and a display unit 50. The display unit 50 is, for example, an operation panel, and is a display device for notifying the user of information from the image forming apparatus 1. It can also display and input information. The control board 60 is equipped with a control unit 61, which is a control unit for controlling the image forming apparatus 1. The control unit 61 collectively controls the operation of the image forming apparatus 1, including control of the drive source related to the transport of the paper 21 and control related to image formation. The control unit 61 includes a memory unit (not shown), and model information is stored in the memory unit beforehand, for example, at the time of shipment from the factory. The toner remaining amount detection units 62Y, 62M, 62C, and 62K are units for detecting the amount of toner remaining in the toner containers 6Y, 6M, 6C, and 6K. The image forming unit includes components that contribute to the formation of an image on the paper 21.

[0019] [Cartridge installation configuration] Next, the installation configuration of the cartridge 12 of the first embodiment will be described with reference to FIGS. 2 and 3. FIGS. 2 and 3 are schematic perspective views of a printer serving as an image forming apparatus in which the cartridge 12 can be detachably attached to the image forming apparatus 1. As shown in FIGS. 2 and 3, the side where a door 40 (described later) is provided is the front side, and the opposite side is the back side. The cartridge 12 (toner container 6) is an example of a unit that can be replaced by being detached from the image forming apparatus 1. A new unit is attached to the image forming apparatus 1 and used until it reaches the replacement time (hereinafter referred to as "lifespan"). The replacement time refers to the time when a predetermined image quality, etc. can no longer be maintained when forming images using that unit. FIG. 2 illustrates a first door 40 (hereinafter referred to as "door 40") (opening / closing member) provided in the image forming apparatus 1 for cartridge replacement. The first door 40 is a movable member for opening and closing an opening through which the cartridge 12 passes. The door 40 is a door for accessing the cartridge 12 in order to remove the cartridge 12 from the image forming apparatus 1. The operating member 41 is a member that allows the user to operate and open / close the door 40. The second door 42 (hereinafter referred to as the door 42) is a door for accessing the conveying path in order to perform jam processing to remove the stuck paper 21 when the paper 21 becomes jammed during conveyance.

[0020] (Cartridge locking mechanism) FIG. 3A shows the door 40 in a position (open position) that opens the opening. In the state shown in FIG. 2, the door 40 is opened by operating the operating member 41 to move the door 40 in the direction of the arrow in FIG. 3A. The locking mechanism (switching mechanism) will be described below. The locking members 43Y, 43M, 43C, and 43K are members for locking the removal of the cartridges 12Y, 12M, 12C, and 12K, respectively. The locking pins 44Y, 44M, 44C, and 44K are pins for regulating the positions of the locking members 43Y, 43M, 43C, and 43K, respectively. The locking pin 44 can be switched between a convex state and a concave state by a solenoid (not shown). The convex state refers to a state in which the locking pin 44 protrudes toward the image forming apparatus 1 beyond the locking member 43, and the concave state refers to a state in which the locking pin 44 does not protrude toward the locking member 43. When the lock pin 44 is in the convex state, the lock member 43 is fixed to a first state (hereinafter referred to as a locked state) in which the cartridge 12 is locked so that it cannot be removed (removal prohibited), thereby preventing the user from removing the cartridge 12.

[0021] FIG. 3(b) shows the lock pin 44Y in a recessed state. In this state, the lock member 43Y can rotate and move to a position (hereinafter referred to as the "removable position") where the cartridge 12 can be removed (removable). FIG. 3(b) shows a second state (hereinafter referred to as the "unlocked state") in which the yellow cartridge 12Y is unlocked. A user can remove the cartridge 12Y from the image forming apparatus 1 by pulling it out in the direction of the dark arrow (toward the user) in FIG. 3(b). As shown in FIG. 3(a), with this configuration, the cartridge 12 cannot be removed from the image forming apparatus 1 simply by the door 40 being in the open state. As shown in FIG. 3(b), when the door 40 is open and the lock pin 44 is in the recessed state, the cartridge 12 can be removed in the direction of the arrow (toward the user) of the front of the image forming apparatus 1.

[0022] The lock pin 44 is controlled by the control unit 61, which is configured to switch between a state in which removal of the cartridge 12 is permitted (hereinafter referred to as removal permitted) and a state in which removal is prohibited (hereinafter referred to as removal prohibited).

[0023] As described above, the image forming apparatus 1 in FIG. 3 includes a plurality of cartridges 12 (toner containers 6) and one door 40 that can be placed in an open or closed position. A locking mechanism is provided for each cartridge 12, and is placed in a released state (unlocked state) so that the cartridge 12 can be removed when the cartridge 12 is replaced. On the other hand, the locking mechanism is placed in a locked state so that the cartridge 12 cannot be removed when the cartridge 12 is not replaced. Here, the locking mechanism includes a locking member 43 and a locking pin 44. The locking mechanism is a switching mechanism that can switch between a restricted state that restricts removal of the cartridge 12 from the device main body and an unrestricted state that does not restrict removal. The control unit 61 controls the locked state and the released state of the locking mechanism.

[0024] [Control configuration] FIG. 4 is a block diagram of the control configuration. The control unit 61 is composed of a CPU and other components, and is responsible for managing information about the cartridge 12, managing the cartridge's lifespan, and switching between locking and unlocking. The management control unit 202 has a one-chip microcomputer (not shown) with built-in memories such as ROM and RAM, and controls the operation of each component of the printer engine. The paper transport control unit 203 drives the paper feed roller 25 for feeding the paper 21 and rotates and stops the transport roller 26 for transporting the paper 21, according to instructions from the management control unit 202. The high-voltage control unit 204 controls the output of high voltages for charging, developing, and transferring, according to instructions from the management control unit 202. The optical system control unit 205 drives and stops the scanner motor (not shown) of the laser scanner 11 and turns on and off the laser, according to instructions from the management control unit 202. The sensor input control unit 206 outputs information (detection results) detected by the register sensor 28 and the paper presence / absence sensor 53 in the ejection section to the management control unit 202. The fixing temperature control unit 207 controls the temperature of the fixing unit 30 to a temperature specified by the management control unit 202. The power control unit 209 supplies or stops the power supply required by each control unit when the power is turned on or off, when switching to or returning from the power saving mode. The power saving mode is a mode in which, when no image is being formed on the paper 21, the device operates with less power than is consumed during image formation.

[0025] The lock control unit 210 manages information about the cartridge 12 and manages the lifespan of the cartridge 12. The lock control unit 210 further has a lock condition determination control unit 230 and an unlock condition determination control unit 220. The lock condition determination control unit 230 determines whether the conditions for implementing locking are met and implements locking of consumables. The unlock condition determination control unit 220 determines whether the conditions for releasing locking are met and releases the lock. The lock control unit 210, which has the lock condition determination control unit 230 and the unlock condition determination control unit 220, functions as a determination means for determining whether to implement locking or whether to release the lock.

[0026] The cartridge 12 has a subordinate information storage unit 70 that stores consumable subordinate information, and a lifespan information storage unit 71 that stores consumable lifespan information. The consumable subordinate information is, for example, information indicating a serial number uniquely determined for each cartridge 12. The consumable lifespan information is, for example, information indicating the lifespan of each cartridge 12. The subordinate information storage unit 70 and the lifespan information storage unit 71 are each connected to the lock control unit 210 of the control unit 61 when the cartridge 12 is attached to the image forming apparatus 1.

[0027] The consumables information storage unit 72, which is a first storage unit, is disposed in the image forming apparatus 1 and is a non-volatile storage unit for storing the contents of the subordinate information storage unit 70 and the lifespan information storage unit 71. The consumables information storage unit 72 is used to detect that the cartridge 12 has been replaced.

[0028] The display unit 50 is used to notify the user of the printer status (for example, whether it is ready to print or that the cartridge 12 has reached the end of its life) and the operation of replacing the cartridge 12. The control unit 61 functions as a notification unit that notifies the user of first information related to the life or replacement of the cartridge 12, and second information related to an abnormality in the cartridge 12. The display unit 50 also has a function such as a touch panel, and the user can input or set predetermined information by touching a predetermined part of the screen displayed on the display unit 50.

[0029] [Consumables dependent information and consumables life information] Table 1 shows the contents stored in the subordinate information storage unit 70Y, which is the second storage means. Table 2 shows the contents stored in the lifespan information storage unit 71Y. Tables 1 and 2 are tables in which the first column stores each item and the second column stores the corresponding value. The contents stored in the subordinate information storage unit 70Y are a serial number (hereinafter referred to as the serial number) unique to each cartridge 12, model information of the image forming apparatus 1 in which the cartridge 12 is used, and cartridge color information indicating the color of the cartridge 12. This stored content is not updated by the control unit 61 (more specifically, the lock control unit 210). For example, the subordinate information storage unit 70Y for yellow stores the serial number "12345," model information "LBPXXXX," and cartridge color information "Y."

[0030] [Table 1]

[0031] The life information storage unit 71Y stores the life judgment rotation time of the photosensitive drum 13Y and the accumulated rotation time of the photosensitive drum 13Y. The accumulated rotation time of the photosensitive drum 13Y is accumulated while the photosensitive drum 13Y is rotating during operation of the image forming apparatus 1 and is updated as needed. The control unit 61 uses the values ​​of the life judgment rotation time and the accumulated rotation time to calculate the remaining life of the photosensitive drum 13Y, which is related to the rotation time. For example, Table 2 stores the life judgment rotation time of the photosensitive drum 13Y as 10,000 seconds and the accumulated rotation time as 6,000 seconds. Therefore, the usage amount can be expressed as 6,000 / 10,000×100=60%, and the remaining life of the photosensitive drum 13Y (hereinafter referred to as the remaining life) is 40% (=100%−60%).

[0032] [Table 2]

[0033] The life information storage unit 71Y stores the life judgment rotation distance of the photosensitive drum 13Y and the accumulated rotation distance of the photosensitive drum 13Y. The accumulated rotation distance of the photosensitive drum 13Y is accumulated while the photosensitive drum 13Y is rotating during operation of the image forming apparatus 1 and is updated as needed. The control unit 61 calculates the remaining life related to the rotation distance of the photosensitive drum 13Y using the values ​​of the life judgment rotation distance and the accumulated rotation distance. For example, Table 2 stores that the life judgment rotation distance of the photosensitive drum 13Y is 5000 m (meters) and the accumulated rotation distance is 3500 m. Therefore, the usage amount expressed as a percentage is 3500 / 5000×100=70%, and the remaining life of the photosensitive drum 13Y is 30% (=100%−70%).

[0034] The remaining amount of toner container 6Y in Table 2 is the amount of toner remaining in toner container 6Y detected by toner remaining amount detection unit 62Y and is stored as needed. Generally, the remaining amount of toner is calculated by accumulating the number of pixels in an image formed by laser scanners 11Y, 11M, 11C, and 11K. Note that the remaining amount of toner may also be calculated by other methods. In Table 2, the smallest value among the three remaining amounts (remaining life)—the remaining life calculated using the cumulative rotation time, the remaining life calculated using the cumulative rotation distance, and the remaining toner amount—is the remaining amount of cartridge 12Y. Note that the information with the smallest value among the three remaining life values ​​is hereinafter referred to as minimum life information (an acquired value related to the amount of cartridge usage).

[0035] In the example of Table 2, the remaining life is determined to be 40% from the cumulative rotation time, 30% from the cumulative rotation distance, and 25% for the remaining toner. Based on this, the control unit 61 considers the remaining life of cartridge 12Y to be the minimum life information, and sets the minimum life information to 25%. In this manner, the control unit 61 functions as an acquisition unit that acquires minimum life information from multiple remaining lifes determined by different means and stored in the life information storage unit 71 of cartridge 12, and determines the acquired minimum life information as the life of cartridge 12. In the first embodiment, the life of cartridge 12 is determined based on multiple pieces of information, specifically, the cumulative rotation time, the cumulative rotation distance, and the remaining toner amount. However, the life of cartridge 12 may also be determined based on one piece of information, specifically, any one of the cumulative rotation time, the cumulative rotation distance, and the remaining toner amount. Furthermore, other information correlated with the life of cartridge 12 may also be used.

[0036] The remaining unlock amount of the cartridge 12Y in Table 2 is a preset remaining amount setting value (hereinafter referred to as the remaining amount setting value) for unlocking the locking mechanism when the remaining amount of the cartridge 12Y falls below this value. When the remaining life of the cartridge 12Y falls below the remaining unlock amount, the control unit 61 unlocks the locking mechanism. The control unit 61 functions as a first determination unit that determines that it is time to replace the toner when the amount of toner contained in the toner container 6 falls below the preset remaining amount setting value. In the example of Table 2, the control unit 61 unlocks the locking mechanism when the minimum life information falls below 5%. Note that the same applies to other colors, so a description will be omitted. The case where the control unit 61 determines that it is time to replace the cartridge 12 based on the minimum life information and the remaining unlock amount and releases the locking mechanism is hereinafter referred to as "locking mechanism release." In this way, the control unit 61 obtains the life (usage) of the cartridge 12 based on at least one of the rotation time of the photosensitive drum 13, the rotation distance of the photosensitive drum 13, and the number of pixels of the image data.

[0037] [Consumables information storage section] Table 3 shows the information stored in the consumables information storage unit 72. The consumables information storage unit 72 stores information selected from the information stored in each storage unit (70, 71) of each color cartridge 12. Here, serial numbers for comparison, the locking status of each locking mechanism, and minimum lifespan information are stored.

[0038] [Table 3]

[0039] Table 3 is a table in which the first column stores each color, the second column stores each item for each color, and the third column stores the value corresponding to each item. For example, for yellow (Y), the serial number is stored as "12345" read from the subordinate information storage unit 70Y. The lock status is stored as information when the control unit 61 controls the lock mechanism ("locked" or "unlocked"), and the lock status is stored as "locked." The minimum life information is stored as "25%" read from the life information storage unit 71Y.

[0040] [Control of locking mechanism activation and deactivation during image formation] Here, the method of processing the lock mechanism by the control unit 61 will be described with reference to the flowchart in Fig. 5. The flowchart in Fig. 5 shows the flow of the lock mechanism release process for releasing the lock mechanism when the remaining life of the cartridge 12 falls below the unlock remaining amount (below a predetermined value) during image formation.

[0041] When the control unit 61 receives an instruction to form an image, it starts the processing from step (hereinafter referred to as S) 101 onwards. In S101, the control unit 61 performs image formation. In S102, during or after image formation, the control unit 61 determines whether the remaining life of at least one cartridge 12 has reached the criterion for releasing the lock mechanism by referring to the information in Table 2 stored in the life information storage unit 71 via the lock control unit 210. Here, the remaining life of a cartridge 12 having reached the criterion for releasing the lock mechanism means that the cartridge 12 has reached the end of its life. If the lock control unit 210 determines in S102 that the remaining life has reached the criterion, the control unit 61 advances the processing to S103. If the lock control unit 210 determines in S102 that the remaining life has not reached the criterion, the control unit 61 advances the processing to S106. For example, the control unit 61 determines that the remaining life of the yellow cartridge 12Y is 25% based on the minimum life information in Table 3, and determines that the standard is 5% based on the unlock remaining amount in Table 2. The lock control unit 210 compares these and determines that the yellow cartridge 12Y has not reached the standard.

[0042] In S103, the control unit 61 releases the lock by recessing the lock pin 44 of the cartridge 12 whose remaining life has been determined by the lock control unit 210 to have reached the criterion for releasing the lock mechanism. For example, if the remaining life of the yellow cartridge 12Y is 5% or less before unlocking, the lock control unit 210 releases the yellow lock pin 44Y.

[0043] In S104, the control unit 61 causes the lock control unit 210 to store information indicating that the cartridge 12 determined to have reached the end of its life as an unlocked state (for example, "unlocked") in Table 3 of the consumables information storage unit 72. In S105, the control unit 61 causes the display unit 50 to display the following information: the control unit 61 notifies the user that the cartridge 12 has reached the end of its life, and displays a display (such as a replacement instruction) urging the user to replace the cartridge 12 that has reached the end of its life with a new cartridge (hereinafter referred to as a new cartridge), and proceeds to S106. In S106, the control unit 61 determines whether or not there is still an image formation instruction, and if it determines that there is an image formation instruction, the process returns to S101, and if it determines that there is no image formation instruction, the process ends.

[0044] In this way, when the cartridge 12 reaches or falls below a predetermined lifespan, the lock on the cartridge 12 is released. This prevents unnecessary costs from being incurred due to the cartridge 12 being accidentally replaced with another cartridge, for example, a new cartridge, when the cartridge 12 still has lifespan remaining.

[0045] [Detects cartridge abnormalities to determine which unit needs replacement and releases the lock mechanism] In the first embodiment, a case where the driving torque of the cartridge 12 is detected as a detection method for detecting an abnormality in the cartridge 12 (toner container 6) will be described. As described above, the cartridge 12 is usually unlocked when the cartridge 12 reaches or falls below a predetermined lifespan. However, depending on the usage environment and conditions, an abnormality may occur in the cartridge 12 due to factors other than the cumulative rotation distance, cumulative rotation time, and remaining toner amount described above, resulting in poor image quality and a request for replacement by the user. That is, this is a case where the user requests replacement of the cartridge 12 even though, based on the above three pieces of information, none of the numerical values ​​indicate that the cartridge 12 needs to be replaced. In the first embodiment, an abnormality in the driving torque is detected as one of the abnormalities of the cartridge 12. When the user requests replacement, the cartridge in which the abnormality occurred is identified, and the lock of the cartridge 12 to be replaced is released even before the end of the lifespan due to conventional factors.

[0046] Specifically, during image formation, the maximum and average drive torque values ​​of the cartridge 12 during startup and other operations, and the average torque value during normal printing, are periodically monitored to detect whether an abnormality has occurred. Details are described below. The torque detection unit 208, which is the detection unit (torque detection unit) (current detection unit) in FIG. 4, detects the torque of the drive motor (motor) (not shown) of the cartridge 12. Specifically, an ammeter (not shown) connected to the drive motor of the cartridge 12 is used. Under the control of the management control unit 202, the torque detection unit 208 detects the torque of the drive motor by measuring the current (detected value, current value) flowing through the drive motor. The detection results are output to the control unit 61 and sequentially stored in ROM. In the first embodiment, the Y, M, C, and K cartridges 12Y, 12M, 12C, and 12K are each driven by a drive motor (not shown), and the torque of each drive motor (not shown) is detected independently. The control unit 61 predicts (determines) whether an abnormality has occurred in the cartridge 12 based on the torque value of the drive motor detected by the torque detection unit 208.

[0047] [torque] FIG. 6 shows the relationship between the change in torque (detection current) over time and the threshold current (I_th) for determining an abnormality, showing the detection current versus page count. The graph in FIG. 6 plots page count on the horizontal axis and detection current (mA) on the vertical axis. It also shows the threshold current I_th for determining an abnormality and the end of life. The page count is an example of information indicating the progress of use of the cartridge 12. The solid line plot shows the change in torque under normal conditions when no abnormalities occur, and the torque remains below the threshold current I_th within the conventional lifespan. The solid line plot indicates a state in which no torque abnormalities occur and good image formation is possible.

[0048] On the other hand, the dashed line plot shows an example of a case where torque increases as the cartridge 12 is used, and in this case, the torque increases rapidly in the latter half of the period leading up to the end of its life. The torque increase that occurs as use progresses does not itself immediately cause device failure and usually has no impact. However, depending on the cause of the torque increase, even within the life (before the end of its life), it is possible that it may be accompanied by phenomena such as streaked images due to poor cleaning, development streaks due to reduced developability, or image defects due to reduced charging. Here, causes of torque increase include, for example, blade wear, roller sliding resistance, and dirt on various rollers.

[0049] Here, a case will be described in which an abnormality determination for the cartridge 12 is performed when a user recognizes some image defect within the cartridge's life and requests replacement of the cartridge 12. Specifically, the control unit 61 compares the currently detected current I with a threshold current I_th1 for determining abnormality of the cartridge 12, which is pre-stored in the ROM, to determine whether the cartridge 12 is in an abnormal state. In the first embodiment, the currently detected current I is a value calculated from a moving average of data for the most recent 100 jobs. The control unit 61 compares the detected current I with the threshold current I_th1, and determines that the cartridge 12 is in a replaceable state if the current torque value is equal to or greater than the threshold for determining an abnormal value. When a replacement request is received from the user, the control unit 61 determines whether or not there is an abnormality in the cartridge 12 based on the detection result by the torque detection unit 208, and if there is an abnormality, identifies the cartridge 12 that has the abnormality. Specifically, the control unit 61 determines that there is an abnormality (abnormality detection) if the current detected by the torque detection unit 208 is equal to or greater than a preset threshold current. The method for calculating the detected current I is not limited to this, and the number of data used for calculation and the calculation method may be determined by other methods. For example, they may be set appropriately depending on the print volume of the image forming apparatus 1, etc.

[0050] The torque measurement method is not limited to the above-described methods. For example, methods using strain gauges, magnetic sensors, acceleration sensors, optical methods, torsion springs, piezoelectric elements, and the like may be used. In the strain gauge method, a strain gauge is attached to the rotating part, and torque is measured based on the amount of deformation caused by torque application. In the magnetic sensor method, a magnetic sensor is attached to the rotating part, and torque is measured based on changes in the magnetic field. In the optical method, torque is measured by attaching a reflector to the rotating part and detecting light reflected from a light source with a photodetector. In the acceleration sensor method, an acceleration sensor is attached to the rotating part, and torque is measured based on changes in acceleration caused by rotation. In the torsion spring method, torsion springs are placed on the rotating body and the detection unit, and when the rotating body rotates, deformation occurring in the torsion springs is detected to measure torque. In the piezoelectric element method, torque is measured by detecting the voltage generated by stress applied to the piezoelectric element when torque is applied to the rotating body. The method to be used for measuring torque may be determined depending on the shape, size, rotation speed, measurement accuracy, etc. of the rotating part to be detected.

[0051] [Replacement diagnosis process when a user requests a cartridge replacement] 7 shows the flow of abnormality detection (replacement diagnosis) of the cartridge 12 when the user requests replacement of the cartridge 12. When the user executes replacement diagnosis of the cartridge 12 by operating the display unit 50 (operation panel), the control unit 61 starts the processing from S201 onwards.

[0052] In S201, the control unit 61 receives a replacement diagnosis of the cartridge 12 and starts the replacement diagnosis. In S202, the control unit 61 refers to the detection result of the torque detection unit 208, specifically the current detection result (current detection data). In S203, the control unit 61 compares the detected current I with a threshold current I_th1. The control unit 61 determines whether the detected current I is equal to or greater than the threshold current I_th1. Here, the control unit 61 compares the detected current I with the threshold current I_th1 for each of the Y, M, C, and K cartridges 12, and determines whether the detected current I is equal to or greater than the threshold current I_th1 for each of the Y, M, C, and K cartridges 12.

[0053] If the control unit 61 determines in S203 that there is at least one cartridge 12 whose detected current I is equal to or greater than the threshold current I_th1, the process proceeds to S204. On the other hand, if the control unit 61 determines in S203 that there is no cartridge 12 whose detected current I is equal to or greater than the threshold current I_th1, the process proceeds to S208.

[0054] In S204, the control unit 61 determines the replaceable cartridge 12 (corresponding cartridge). In S205, the control unit 61 displays the replaceable (replacement target) cartridge 12 on the display unit 50 (operation panel) and displays instructions for the operation when performing the replacement (operation instructions). In S206, the control unit 61 releases the lock pin 44 of the corresponding cartridge 12. The user unlocks the door sequentially according to the operation and performs the replacement work for the corresponding cartridge 12. In S207, the control unit 61 displays on the display unit 50 (operation panel) a message requesting the user to perform an operation to notify that the replacement of the cartridge 12 has been completed. In response to the user's input indicating that the replacement has been completed, the control unit 61 locks the lock pin 44 and performs an end process, thereby ending the series of replacement flows.

[0055] In S208, the control unit 61 displays a message on the display unit 50 (operation panel) to reconfirm whether or not an image defect has occurred (reconfirmation instruction). In S209, the control unit 61 waits for input from the user and determines whether or not the user has input that there is an image defect on the display unit 50. If the control unit 61 determines in S209 that the user has input that there is an image defect, the process proceeds to S210. In S210, the control unit 61 displays a message on the display unit 50 prompting the user to request a service technician to take action (service technician action instruction), and ends the series of processes. If the control unit 61 determines in S209 that the user has input that there is no image defect, the occurrence of the image defect is likely to be temporary and the phenomenon has disappeared, and therefore ends the series of processes.

[0056] In this way, when the user requests replacement of the cartridge 12 even though the cartridge has not yet reached the end of its life, the control unit 61 performs an abnormality diagnosis (replacement diagnosis) of the cartridge 12. The control unit 61 then determines whether or not there is an abnormality in the cartridge 12 and determines which cartridge 12 is to be replaced, and releases the lock pin 44 only for the cartridge 12 to be replaced. This makes it possible to prevent unnecessary replacement and replacement of the wrong cartridge 12.

[0057] In the first embodiment, the locking mechanism of a color image forming apparatus having a plurality of cartridges has been described, but similar control is also possible in a monochrome image forming apparatus having only one cartridge. As described above, according to the first embodiment, it is possible to improve the usability of the locking mechanism of the replaceable unit.

[0058] [Variation 1] Although the first embodiment has been described using the configurations shown in FIGS. 2 and 3, similar control can be performed with the door and door lock configuration shown in FIG. 8. The configuration shown in FIG. 8(a) illustrates a case in which a plurality of doors 45, which are opening / closing members, are provided corresponding to the cartridges 12. Specifically, the image forming apparatus 1 is provided with doors 45Y, 45M, 45C, and 45K and lock pins 47Y, 47M, 47C, and 47K. Each door 45 is locked when the lock pin 47 is moved downward in the figure (locked state), and unlocked when the lock pin 47 is moved upward in the figure (unlocked state). The control unit 61 controls the opening and closing of each door 45 by switching the state of each lock pin 47. In S205 of the replacement diagnosis process shown in FIG. 7, the control unit 61 sets the lock pin 47 corresponding to the corresponding cartridge 12 to the unlocked state and sets the door 45 to the open position. The image forming apparatus 1 having the configuration shown in FIG. 8(a) may further include locking members 43Y, 43M, 43C, and 43K, and locking pins 44Y, 44M, 44C, and 44K.

[0059] As described above, the image forming apparatus 1 in FIG. 8(a) includes a plurality of cartridges 12 and doors 45Y, 45M, 45C, and 45K that are provided for each cartridge 12 and can be in an open or closed position. A locking mechanism is provided for each door 45, and is released to place the door 45 in the open position so that the cartridge 12 can be removed when the cartridge 12 is replaced. On the other hand, the locking mechanism is released to place the door 45 in the closed position so that the cartridge 12 cannot be removed when the cartridge 12 is not replaced. The locking mechanism includes a lock pin 47. The control unit 61 functions as a switching mechanism that switches the locking mechanism between the released state and the locked state.

[0060] [Variation 2] FIG. 8(b) shows a case where the image forming apparatus 1 is provided with one door 52 for four cartridges 12Y, 12M, 12C, and 12K. The door 52 is locked when the lock pin 47 is moved downward in the figure (locked state), and is unlocked when the lock pin 47 is moved upward in the figure (unlocked state). The control unit 61 controls the opening and closing of the door 52 by switching the state of the lock pin 47. In S205 of the replacement diagnosis processing in FIG. 7, the control unit 61 sets the lock pin 47 to the unlocked state and the door 52 to the open position. Note that the image forming apparatus 1 configured as shown in FIG. 8(b) may further include lock members 43Y, 43M, 43C, and 43K and lock pins 44Y, 44M, 44C, and 44K.

[0061] As described above, the image forming apparatus 1 in FIG. 8(b) includes a plurality of cartridges 12 and one door 52 that can be placed in an open or closed position. The locking mechanism is provided on the door 52, and is released when the cartridge 12 is to be replaced, so that the door 52 can be placed in the open position to allow the cartridge 12 to be removed. On the other hand, when the cartridge 12 is not to be replaced, the locking mechanism is placed in a locked state, so that the door 52 can be placed in the closed position to prevent the cartridge 12 from being removed. The locking mechanism includes a locking pin 47. The control unit 61 functions as a switching mechanism that switches the locking mechanism between the released state and the locked state.

[0062] FIG. 17 is a flowchart for explaining permission and prohibition of switching from the regulated state to the non-regulated state. In S601, the control unit 61 obtains an acquired value related to the use of the cartridge 12. In S602, the control unit 61 determines whether the acquired value is greater than a threshold value. If the control unit 61 determines that the acquired value is greater than the threshold value in S602, the process proceeds to S603. If the control unit 61 determines that the acquired value is equal to or less than the threshold value, the process proceeds to S604. In S603, the control unit 61 permits switching from the regulated state to the non-regulated state and ends the process. In S604, the control unit 61 determines whether an abnormality exists using the method described above. If the control unit 61 determines that an abnormality exists in S604, the process proceeds to S603. If the control unit 61 determines that no abnormality exists, the process proceeds to S605. In S605, the control unit 61 prohibits switching from the regulated state to the non-regulated state and ends the process. In this way, if the torque detection unit 208 does not detect an abnormality during the first period until the acquired value reaches the threshold value, the control unit 61 controls the locking mechanism so as not to allow switching from the regulated state to the non-regulated state. On the other hand, if the detection unit 208 detects an abnormality in the cartridge, the control unit 61 controls the locking mechanism so as to allow switching from the regulated state to the non-regulated state. During the second period after the acquired value reaches the threshold value, the control unit 61 controls the locking mechanism so as to allow switching from the regulated state to the non-regulated state.

[0063] As described above, according to the first embodiment, when a user desires to replace a cartridge, the user is correctly notified of the consumables that need to be replaced, preventing the user from accidentally replacing a cartridge that does not need to be replaced, thereby improving usability during replacement. [Example]

[0064] [Identifying the unit to be replaced through diagnostic imaging and unlocking the locking mechanism] In Example 2, an image forming apparatus having a reading device that reads an image formed on paper 21 is described, in which image diagnosis is performed and, based on the diagnosis results, a decision is made as to whether to replace cartridge 12 and door lock control for cartridge 12 is performed.

[0065] [Control configuration] FIG. 9 is a control block diagram of the second embodiment; differences from FIG. 4 will be described and other explanations will be omitted. In the second embodiment, when a user finds an image defect before the end of the original cartridge 12's life and requests replacement, an image diagnosis is performed to identify the cartridge 12 in which an abnormality has occurred, and the lock of the cartridge 12 to be replaced is released. In the second embodiment, the image diagnosis control unit 211, which will be described later, functions as a detection unit that detects an abnormality in the cartridge 12 (toner container 6). Furthermore, when a replacement request is received from the user, the control unit 61 determines whether or not there is an abnormality in the cartridge 12 based on the diagnosis result by the image diagnosis control unit 211, and, if it is determined that there is an abnormality, functions as a second determination unit that identifies the cartridge 12 in which there is an abnormality.

[0066] When the user performs a replacement diagnosis of the cartridge 12 from the display unit 50, the control unit 61 receives image data for the image diagnosis and temporarily stores the received image data in a memory in the management control unit 202. Then, the management control unit 202 controls the image forming device based on the image data stored in the memory to form an image on the paper 21. When a request to perform image diagnosis is made, the image diagnosis control unit 211 controls the reading unit in accordance with instructions from the management control unit 202, reads the formed image with the reading unit, and determines whether there is an image defect and identifies the unit causing the defect.

[0067] [Reading device] FIG. 10 is a schematic cross-sectional view of an image forming apparatus 2 having a document reading unit 300, which is a reading section used in the second embodiment. A document G is placed on a tray 301 of the document reading unit 300. A feed roller 302 feeds the document G on the tray 301 to a conveying path 304. At this time, a separation roller 303 prevents double feeding of documents G. A reading section 305 has a contact image sensor, optically reads an image of the surface of the document G conveyed along the conveying path 304, and outputs image data representing the read result to a control section 61. The image data is, for example, information representing red (R), green (G), and blue (B) for each pixel using 8 bits (0 to 255). Thereafter, the document G is discharged to a tray 307 by a discharge roller 306. The configuration of the image forming apparatus 2 is the same as that of the image forming apparatus 1 in FIG. 1, and the same reference numerals are used, and a description thereof will be omitted. Although not shown in FIG. 10, the image forming apparatus 1 also includes a display unit 50.

[0068] [Image diagnosis processing when a user requests cartridge replacement] 11 is a flowchart showing the determination of a unit to be replaced by image diagnosis and the release of the lock mechanism in the second embodiment. When the user executes the replacement diagnosis of the cartridge 12 by operating the display unit 50, the control unit 61 starts the processing from S301 onwards. In S301, the control unit 61 receives a request from the user to replace the cartridge 12 and starts the replacement diagnosis. In S302, the control unit 61 starts the image diagnosis. The detailed processing of the image diagnosis will be described later with reference to FIG. 12.

[0069] In S303, the control unit 61 determines whether or not there is an image defect. Specifically, the control unit 61 determines whether or not there is a defect in the image. The control unit 61 functions as an image defect detection unit that detects image defects in the test image based on image data read by the document reading unit 300. If the control unit 61 determines in S303 that there is an image defect, it proceeds to S304. If the control unit 61 determines in S303 that there is no image defect, it ends the series of processes. Note that if the diagnosis shows that there is no image defect, the display unit 50 may display, in response to a replacement request from the user, that no abnormality has occurred as a result of the diagnosis and that there is no need to replace the cartridge 12.

[0070] In S304, the control unit 61 determines whether the image defect is caused by the cartridge 12. If the control unit 61 determines in S304 that the image defect is caused by the cartridge 12, the process proceeds to S305. Whether the image defect is caused by the cartridge 12 will also be described with reference to FIG. 12. If the control unit 61 determines in S304 that the image defect is not caused by the cartridge 12, the process proceeds to S309. In S305, the control unit 61 unlocks the cartridge 12 that is causing the image defect. In S306, the control unit 61 displays the cartridge 12 to be replaced on the display unit 50, and displays operating instructions to the user.

[0071] In S307, the control unit 61 waits for the door 40 to be opened and closed, and for the user to perform and complete the replacement work. In S308, the control unit 61 displays a message on the display unit 50 requesting the user to perform an operation to complete the replacement. In S308, after the user has completed the operation, the control unit 61 locks the cartridge 12 and ends the series of processes. In S309, the control unit 61 displays a message for a service technician on the display unit 50 and ends the series of processes.

[0072] (Image diagnosis processing) Fig. 12 is a flowchart showing an example of the image diagnosis processing performed by the control unit 61 in S302 of Fig. 11. Fig. 13(a) shows a test image of Example 2. Note that the Y direction in Fig. 13(a) is the transport direction of the paper 21 and is also called the sub-scanning direction. The X direction is the direction perpendicular to the Y direction within the plane of the paper 21 and is also called the main scanning direction.

[0073] The test image has a plurality of reference images formed in each of a plurality of reference colors in region A. In Example 2, the plurality of reference colors are yellow, magenta, cyan, and black, and reference images PY, PM, PC, and PK are formed in region A. The test image also has a determination image Pb in region B, in which yellow, magenta, cyan, and black, each with a density of 10%, are superimposed. Note that the density of each color is not limited to 10%. The determination image Pb is formed as large as possible.

[0074] In S401, the control unit 61 forms a test image. In S402, the control unit 61 causes the user to set the document G on which the test image has been formed in the tray 301 of the document reading unit 300, and causes the document reading unit 300 to read the paper 21 on which the test image has been formed. The document reading unit 300 outputs the read image data (read image data) to the control unit 61.

[0075] As shown in Table 4(A), the control unit 61 determines the color values ​​in the RGB color space of the reference images PY, PM, PC, and PK and the area where the reference images PY, PM, PC, and PK and the determination image Pb are not formed (hereinafter referred to as the background area), and stores the determined values ​​in memory. The color values ​​of the reference images PY, PM, PC, and PK can be the average color values ​​of a specific pixel or all pixels in the reference image. The color value of the background area can be the average color value of a specific pixel or all pixels in the background area. For example, the control unit 61 obtains values ​​(R, G, B) = (255, 212, 0) as a result of reading the reference image PY. The control unit 61 obtains values ​​(R, G, B) = (239, 236, 237) as a result of reading the background area.

[0076] [Table 4]

[0077] In S403, the control unit 61 converts the color values ​​in the RGB color space of the reference images PY, PM, PC, and PK obtained in S402 and the background region into color values ​​in the L*a*b* color space using a known method. Table 4(B) shows the color values ​​shown in Table 4(A) converted into color values ​​in the L*a*b* color space. Hereinafter, unless otherwise specified, "color space" refers to the L*a*b* color space, and "color values" refers to color values ​​in the L*a*b* color space. For example, the control unit 61 obtains the following values ​​as a result of color conversion for the reference image PY: (L*, a*, b*) = (87.7, -6.3, 99.7). Similarly, the control unit 61 obtains the following values ​​as a result of color conversion for the background region: (L*, a*, b*) = (91, -0.2, 4.2).

[0078] In S404, the control unit 61 normalizes the color values. First, the control unit 61 subtracts the color values ​​of the background region from the color values ​​of the reference images PY, PM, PC, and PK shown in Table 4(B). This process corresponds to setting the color values ​​of the background region as the origin in the color space. Table 4(C) shows the values ​​obtained by subtracting the color values ​​of the background region from the color values ​​of the reference images PY, PM, PC, and PK shown in Table 4(B). For example, the control unit 61 obtains the values ​​(L*, a*, b*) = (-3.3, -6.2, 95.6) for yellow.

[0079] The control unit 61 then normalizes the color values ​​shown in Table 4(C) to vectors of length 1 in color space. Table 4(D) shows the results of normalizing the color values ​​in Table 4(C). For example, the control unit 61 obtains a normalized value for yellow of (L*, a*, b*) = (-0.034, -0.064, 0.997). This process corresponds to determining the unit vectors for each vector in Table 4(D). Hereinafter, the color values ​​of the reference images PY, PM, PC, and PK shown in Table 4(D) will be referred to as the reference vectors for Y, M, C, and K, respectively.

[0080] Similarly, the control unit 61 converts the color values ​​in the RGB space of each pixel of the determination image Pb read by the document reading unit 300 into color values ​​in the L*a*b* color space, subtracts the color values ​​of the background region, and then converts the converted values ​​into unit vectors. Hereinafter, this unit vector of the pixel of the determination image Pb will be referred to as a determination vector.

[0081] In S405, the control unit 61 determines the amount of change. Here, the control unit 61 determines the pixel with the highest density and the pixel with the lowest density in the determination image Pb, which are determined from the image data read from the determination image Pb, based on the color value of each pixel. Then, the control unit 61 calculates the inner product of the determination vector of the pixel with the highest density and the reference vectors of Y, M, C, and K, and the inner product of the determination vector of the pixel with the lowest density and the reference vectors of Y, M, C, and K.

[0082] For example, Table 5(A) shows the judgment vectors of the highest and lowest density pixels in the judgment image Pb when the test image is formed as shown in Figure 13(b). The test image shown on the far right of Figure 13(b) is formed by superimposing the four colors shown on the left. In Figure 13(b), density unevenness occurs in magenta in the sub-scanning direction, resulting in a high-density region (or normal-density region) F2 and a low-density region F3 in the judgment image Pb. Pb(high density) in Table 5(A) is the color value of the high-density region F2, and Pb(low density) is the color value of the low-density region F3.

[0083] [Table 5]

[0084] Table 5(B) shows the dot products of the determination vectors shown in Table 5(A) and the reference vectors for Y, M, C, and K. In S405, the control unit 61 calculates the difference (absolute value) between the dot product with the pixel of maximum density and the dot product with the pixel of minimum density for each reference color as the amount of change, as shown in Table 5(B). Because the reference vector and the determination vector are both unit vectors, the dot product of the reference vector and the determination vector has a value that corresponds to the angle between the reference vector and the determination vector. Therefore, the amount of change shown in Table 5(B) corresponds to the maximum amount of change in the angle of the determination vector for each of the multiple pixels in the determination image Pb relative to the reference vector.

[0085] In S406, the control unit 61 determines whether all of the amounts of change calculated in S405 are greater than a first threshold value. The first threshold value can be the same regardless of color, or can be different for each color. If the control unit 61 determines that the amounts of change for all colors are equal to or less than the first threshold value, it determines that there are no image defects, in other words, that there are no image defects caused by the cartridge 12, and ends the image diagnosis process.

[0086] On the other hand, if the control unit 61 determines in S406 that a color exists whose change amount is greater than the first threshold, the process proceeds to S407. In S407, the control unit 61 determines that an image defect has occurred. This is because the amount of change in the angle of the judgment vector with respect to the reference vector of a certain reference color increases as the change in that reference color in the judgment image Pb increases. In this case, the cartridge 12 causing the image defect corresponds to a color whose change amount is greater than the first threshold. The control unit 61 determines the occurrence of the image defect and the cartridge 12 causing the image defect, and then ends the image diagnosis process.

[0087] 10, the case where an image is read and diagnosed using the document reading unit 300 has been described above, but the diagnosis may also be implemented in a configuration where a reading device is incorporated, for example, in a transport path after fixing or in a double-sided transport path, rather than in a configuration having the document reading unit 300. In this case, instead of forming an image once and then having the user perform the reading operation, image formation and image reading become possible automatically after the diagnosis starts, making it possible to perform the diagnosis with simpler operations.

[0088] As described above, according to the second embodiment, when a user desires to replace a cartridge, the user is correctly notified of the consumables that need to be replaced, preventing the user from accidentally replacing a cartridge that does not need to be replaced, thereby improving usability during replacement. [Example]

[0089] In the above-described examples, the determination by torque detection in Example 1 and the determination by image diagnosis in Example 2 are both controlled by the control unit 61 in the engine. In Example 3, however, a configuration will be described in which these determinations are performed by calculation processing on an external server via an external network.

[0090] [Network configuration of image forming device] FIG. 14 shows an example of a network configuration of an image forming system according to a third embodiment, in which a plurality of image forming apparatuses 1 and 2 are connected. The image forming apparatuses 1 and 2 are installed in a user environment E1 where a user exists and connected to a local network NW1, which may be, for example, a local area network (LAN). The management server 400 is installed in a remote environment E2. The remote environment E2 is connected to the local network NW1 via an external network NW2. The external network NW2 may be, for example, the Internet or a virtual private network (VPN). Each of the local network NW1 and the external network NW2 may include any number of network devices of any type, such as routers, switches, gateways, wireless access points, and base stations.

[0091] In user environment E1, a user uses image forming apparatus 1 or image forming apparatus 2. As described above, image forming apparatuses 1 and 2 print an arbitrary image through an image formation process. During this image formation, the detection results detected by torque detection unit 208 of embodiment 1 are acquired, stored in memory, and sent to management server 400. The server determines the state of cartridge 12 from the sent data through averaging processing, regression processing, and the like. That is, the determination of S102 in FIG. 5, which was previously performed by control unit 61, is now performed by management server 400. The determination results thus obtained by management server 400 are reported via external network NW2 and local network NW1 to, for example, display units 50 installed in image forming apparatuses 1 and 2. Alternatively, the results may be reported on a monitoring tool 500, which will be described below in FIG. 15.

[0092] Furthermore, the management server 400 used here may be implemented as, for example, an application server, database server, or cloud server using a high-performance general-purpose computer. When analysis is performed using external storage and computing means connected via a network, statistical processing such as averaging and regression can be performed using a large amount of data without being limited by the performance and capacity of the CPU built into the image forming apparatus. This improves the accuracy of torque abnormality detection and cartridge identification. The functions of the management server 400 may be provided by a single device, or by multiple physically separate devices working together to function as the management server 400 as a whole.

[0093] [Control configuration] Fig. 15 is a block diagram of the control configuration of the third embodiment. As shown in Fig. 15, the control configuration of the third embodiment is configured by an image forming apparatus 1, a management server 400, and a monitoring tool 500. Note that, in the image forming apparatus 1 of Fig. 15, the same components as those in Fig. 4 are denoted by the same reference numerals, and the description thereof will be omitted.

[0094] The image forming apparatus 1 transmits print data and print instructions sent from a host computer (not shown) to the printer engine. The management server 400 has a management server control unit 410 including a calculation unit 412 and a storage device 414, and is connected to the image forming apparatus 1 and the monitoring tool 500 via a network that allows bidirectional access. The calculation unit 412 executes programs stored in the storage device 414 and reads and writes various data. The calculation unit 412 may be, for example, a CPU or GPU, and the storage device 414 may be directly allocated RAM, HDD, SSD, etc., or may be allocated a virtual environment such as a virtual machine. The management server control unit 410 is connected to a control unit 61 in the image forming apparatus 1, thereby enabling the exchange of information with the control unit 61.

[0095] The monitoring tool 500 is a tool used by a dealer when managing each image forming apparatus, and includes a monitoring tool control unit 510 for receiving information from the management server control unit 410 and an operation display unit 520 for displaying the received information. Here, the operation display unit 520 of the monitoring tool 500 includes a display, keyboard, mouse, etc. (none of which are shown). The form of the monitoring tool 500 is not limited to a personal computer or a server, but may also be a virtual environment such as a virtual machine or a tablet terminal. In FIG. 15, the image forming apparatus 1 can be replaced with the image forming apparatus 2 of FIG. 9.

[0096] [Treatment of Example 3] The operations of the control unit 61, the management server control unit 410, and the monitoring tool 500 in the third embodiment will be described with reference to the flowchart of Fig. 16. The flowchart of Fig. 16 starts when the user requests a diagnosis from the display unit 50 and the control unit 61 receives a diagnosis instruction.

[0097] 16, the processes of S501 and S504 to S511 are the same as the processes of S201 and S203 to S210 in FIG. 7 described in the first embodiment, and detailed description of the processes will be omitted. The process of FIG. 16 is mainly performed by the management server control unit 410. When the replacement diagnosis is started in S501, the control unit 61 of the image forming apparatus 1 performs torque detection, specifically current detection, using the torque detection unit 208 to obtain the detection result. In the third embodiment, the control unit 61 does not perform the processes from S202 onward in FIG. 7, but transmits the detection result to the management server 400 via the network. Then, the management server control unit 410 of the management server 400 performs the processes from S502 onward.

[0098] In the first embodiment, the result of the replacement diagnosis, i.e., information on whether or not a torque abnormality has occurred, and if so, which cartridge 12 the torque abnormality has occurred in, is displayed on the display unit 50 of the image forming apparatus 1. The user then operates the display unit 50 to notify the control unit 61 that replacement of the cartridge 12 has been completed, etc. In the third embodiment, information may be displayed and input not only by the display unit 50 but also by the operation display unit 520 of the monitoring tool 500.

[0099] In S502, the management server control unit 410 starts calculation processing using the detection results sent from the control unit 61 via the calculation device 412 and the storage device 414 (start server data calculation). In S503, the management server control unit 410 performs calculations similar to those performed by the control unit 61 in the first embodiment and acquires the processed current detection results (acquire calculation results). Note that the calculation processing by the management server control unit 410 may be any calculation processing. For example, it may be possible to average all recent data, or to extract the maximum value per day from the most recent month's worth of data and acquire a moving average from the maximum value data for one month to obtain the most recent current output result. Furthermore, the current detection results may be corrected according to the printing conditions. In this way, performing calculation processing on the management server 400 side enables calculations that would be complex and difficult to perform on the control unit 61 side of the image forming apparatus 1. Here, moving average data of the maximum value for one month was used.

[0100] The same applies when the image forming apparatus 1 is replaced with the image forming apparatus 2. For example, the control unit 61 may transmit to the management server 400, for example, the results of reading the test image in S402 among the processes in Fig. 12 performed by the image diagnosis control unit 211. The management server 400 may then perform the processes from S403 to S407 in Fig. 12 using the results of reading the test image transmitted from the image forming apparatus 2. The management server 400 may transmit to the image forming apparatus 2 the results of whether or not an image defect has occurred and, if an image defect has occurred, the results of identifying which cartridge 12 the image defect has occurred in.

[0101] That is, when a user of the image forming apparatus 2 requests replacement, the image forming apparatus 2 and the management server 400 cooperate to perform processing in accordance with the flowchart of FIG. 11 described in the second embodiment. For example, the image forming apparatus 2 performs processing at S302 of FIG. 11 and S410 and S402 of FIG. 12, i.e., forming a test image and reading the test image, and transmits the results to the management server 400. The management server 400 performs processing equivalent to S502 and S503 of FIG. 16, e.g., processing from S403 onward in FIG. 12 and processing from S303 onward in FIG. 11. The diagnosis results, i.e., whether or not there is an image defect and the result of identifying the cartridge 12 if an image defect occurs, may be displayed on the display unit 50 of the image forming apparatus 2 or the operation display unit 520 of the monitoring tool 500. Information indicating the completion of replacement of the cartridge 12 may then be obtained from the display unit 50 or the operation display unit 520. In the third embodiment, the management server control unit 410 or the monitoring tool control unit 510 functions as all or part of the notification unit, the first determination unit, the second determination unit, and the image defect detection unit.

[0102] In this way, when a user requests a replacement diagnosis, a cartridge abnormality diagnosis (replacement diagnosis) is performed to determine whether there is an abnormality and which cartridge is to be replaced, and the lock mechanism of only the cartridge to be replaced is released. This makes it possible to prevent unnecessary replacement and replacement of the wrong cartridge even in the configuration of Example 3.

[0103] Here, an example has been described in which calculations are performed based on detection results stored in the management server 400 when a user issues a replacement request, and a determination is made. However, this is not limiting. For example, the most recent current detection results calculated on the management server 400 may be periodically notified to the memory of the control unit 61 at a predetermined timing, and the determination may be made using the updated detection results. For example, the current detection results calculated by the management server 400 may be updated and stored in the memory of the control unit 61 every day, and the stored results may be referenced. In this case, even if a replacement request is made, the most recent current detection results are already stored in memory, so the image forming apparatus 1 only needs to reference the current detection results, thereby reducing processing time. As in the third embodiment, calculations and regression analyses can be performed on a large amount of data on an external server, making it possible to accurately notify the actual lifespan under conditions suited to the user's usage status.

[0104] As described above, according to the third embodiment, when a user desires to replace a cartridge, the user is correctly notified of the consumables that need to be replaced, preventing the user from accidentally replacing a cartridge that does not need to be replaced, thereby improving usability during replacement. [Explanation of symbols]

[0105] 1. Image forming device 6 Toner container 12 cartridges 61 Control Unit 208 Torque detection unit

Claims

1. an image forming apparatus including: a plurality of cartridges, each having a rotatable roller that carries toner and a storage portion that stores toner to be supplied to the roller; and an apparatus main body to which the plurality of cartridges can be attached and detached in the direction of the rotation axis of the roller; a server connected to the image forming apparatus via a network; an information processing device connected to the server via the network; An image forming system comprising: The device body includes: a switching mechanism capable of switching between a restricting state in which removal of the cartridge from the apparatus main body is restricted and a non-restricting state in which removal is not restricted; a detection unit that detects an abnormality in the cartridge; a control unit that controls the switching mechanism; An image forming unit that forms an image for inspection, the test image includes a first region and a second region; the first region is a region where a reference image is formed, in which a plurality of reference color images are formed on a recording material; the second area is an image forming section where a determination image is formed on a recording material by superimposing a plurality of color images; a reading unit that reads the reference image and the determination image formed on the recording material by the image forming unit; and The control unit controlling the switching mechanism to switch the toner amount in the storage section to the regulated state when the amount of toner in the storage section is greater than a predetermined amount, and to switch the toner amount in the non-regulated state when the amount of toner in the storage section is less than the predetermined amount; Even if the amount of toner in the storage section is greater than a predetermined amount, when the server determines that the detection result from the detection section is abnormal, the server controls the switching mechanism to switch the cartridge determined to be abnormal to the non-regulated state, The server detects an abnormality in the cartridge based on the detection result of the detection unit when an amount of change in density between the reference image and the determination image based on information read from both the reference image and the determination image by the reading unit is greater than a first threshold value, The result of the determination by the server is transmitted to the information processing device and the control unit. An image forming system comprising:

2. the cartridge further includes a photosensitive drum that carries an image developed with the toner supplied from the roller; 2. The image forming system according to claim 1.

3. the device body includes a motor for driving the roller and a current detection unit for detecting a current flowing through the motor; the server has the detection unit, the detection unit detects the abnormality based on the current detected by the current detection unit.

3. The image forming system according to claim 2.

4. The server has the detection unit, the detection unit detects an abnormality in the cartridge based on information read from the test image by the reading unit.

3. The image forming system according to claim 2.

5. The image forming apparatus includes an exposure unit that forms an electrostatic latent image on the photosensitive drum based on input image data, an acquisition unit that acquires an acquired value regarding the amount of toner used in the container, and and the acquiring unit acquires the usage amount of the cartridge based on at least one of a rotation time of the photosensitive drum, a rotation distance of the photosensitive drum, and a pixel count of the image data.

3. The image forming system according to claim 2.

6. The device body includes: an opening through which the cartridge passes when the cartridge is attached to or detached from the apparatus main body; an opening / closing member that is movable between a closed position that closes the opening and an open position that opens the opening; a locking mechanism that can switch between a locked state in which the opening / closing member is locked so as not to move from the closed position to the open position and an unlocked state in which the opening / closing member is allowed to move from the closed position to the open position; and the switching mechanism is the locking mechanism, the locked state is the restricted state, and the unlocked state is the non-restricted state; 3. The image forming system according to claim 2.

7. A plurality of the cartridges is provided, The device body includes: an opening through which the cartridge passes when the cartridge is attached to or detached from the apparatus main body; an opening / closing member that is movable between a closed position that closes the opening and an open position that opens the opening; a locking mechanism that can switch between a locked state in which the opening / closing member is locked so as not to move from the closed position to the open position and an unlocked state in which the opening / closing member is allowed to move from the closed position to the open position; and the switching mechanism is the locking mechanism, the locked state is the restricted state, and the unlocked state is the non-restricted state; 3. The image forming system according to claim 2.

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