JP7347080B2 - Image forming device - Google Patents

Description

The present disclosure relates to an image forming apparatus.

2. Description of the Related Art Conventionally, electrophotographic image forming apparatuses such as LED printers are known. This type of image forming apparatus includes an apparatus main body and a drum cartridge that is removably attached to the apparatus main body. A conventional image forming apparatus including an apparatus main body and a drum cartridge is described in, for example, Patent Document 1.

The image forming apparatus described in Patent Document 1 includes a control section within the apparatus main body. The control section includes a drum counter and a lifespan determining means. The drum counter counts the number of rotations of the photosensitive drum. The life determining means determines that the photosensitive drum has reached the end of its life when the number of rotations of the photosensitive drum counted by the drum counter reaches a photosensitive drum life value. In the image forming apparatus described in Patent Document 1, the life of the drum cartridge (photosensitive drum) is thus managed by the control section provided in the apparatus main body.

Japanese Patent Application Publication No. 2013-50601

However, in the image forming apparatus as described in Patent Document 1, when the drum cartridge includes a charger, the presence or absence of abnormal discharge of the charger is not taken into consideration. For this reason, when a drum cartridge in which abnormal discharge has occurred is used by being attached to the main body of another image forming apparatus, the drum cartridge cannot be properly managed.

The present disclosure makes it possible to appropriately manage a drum cartridge even if a drum cartridge that has been used while being attached to the apparatus main body of another image forming apparatus and in which abnormal discharge has occurred is attached to the apparatus main body of the image forming apparatus. The purpose is to provide technology.

According to a first aspect of the present application, an image forming apparatus including a drum cartridge and a control section is provided. The drum cartridge includes a photosensitive drum, a charger, and a drum memory. The charger charges the surface of the photoreceptor drum. The drum memory stores life count information regarding the life of the drum cartridge and discharge history information regarding abnormal discharge of the charger that occurred in the past. The control unit is capable of executing print processing and stopping print processing. The control unit includes a voltage application circuit that applies a voltage to the charger, and an abnormal discharge detection circuit that detects occurrence of abnormal discharge based on a current value of the voltage application circuit. When the abnormal discharge detection circuit detects the occurrence of the abnormal discharge, the control unit determines that the life count information read from the drum memory is equal to or greater than a first reference value, and that the discharge detected from the drum memory is If the number of abnormal discharges included in the history information is equal to or greater than a predetermined threshold, the printing process is stopped. Further, the control unit may be configured such that the life count information read from the drum memory is equal to or greater than the first reference value, and the number of abnormal discharges included in the discharge history information read from the drum memory is the predetermined number. If the value is not equal to or greater than the threshold value, print processing is executed.

According to a second aspect of the present application, in the image forming apparatus according to the first aspect, the drum memory includes information that abnormal discharge has occurred in the past, and the life count information of the drum cartridge at the time when the abnormal discharge occurred; is stored as the discharge history information.

According to a third aspect of the present application, the image forming apparatus according to the second aspect further includes a display. The control unit can execute a discharge interval determination process and a cleaning request display process. In the discharge interval determination process, when the abnormal discharge detection circuit detects the occurrence of the abnormal discharge, the life count information read from the drum memory and the previous abnormality included in the discharge history information read from the drum memory are determined. It is determined whether the difference between the life count information and the life count information when discharge occurs is smaller than a predetermined value. In the cleaning request display process, when it is determined that the difference is smaller than a predetermined value, a message prompting cleaning of the charger is displayed on the display.

According to a fourth aspect of the present application, in the image forming apparatus according to the third aspect, the control unit can execute a discharge history information update process. In the discharge history information update process, when it is determined that the difference is greater than or equal to a predetermined value, the fact that an abnormal discharge has occurred and the life count information at the time when the abnormal discharge occurred is set as the discharge history information. The data is stored in the drum memory.

In a fifth aspect of the present application, in the image forming apparatus according to the fourth aspect, the control unit is capable of executing a first determination process and a printing stop process when the discharge history information update process is executed. be. In the first determination process, the abnormal discharge occurs after the control unit determines that the life count information read from the drum memory has become larger than a second reference value that is larger than the first reference value. It is determined whether the number of times detected by the abnormal discharge detection circuit is equal to or greater than a first threshold value. In the printing stop process, the abnormal discharge detection circuit determines that an abnormal discharge has occurred after the control unit has determined that the life count information has become larger than the second reference value as a result of the first determination process. When the control unit determines that the number of detected times is equal to or greater than a first threshold, printing processing using the drum cartridge is stopped.

According to a sixth aspect of the present application, in the image forming apparatus according to the fifth aspect, the control section can execute a second determination process and a print stop process. In the second determination process, abnormal discharge occurs after the control unit determines that the life count information has become larger than a second reference value, which is larger than the first reference value, as a result of the first judgment process. When it is determined that the number of times that the abnormal discharge detection circuit detects that the abnormal discharge has occurred is not equal to or greater than the first threshold value, the control unit determines that the life count information has become larger than the first reference value. It is then determined whether the number of times the abnormal discharge detection circuit detects that abnormal discharge has occurred is equal to or greater than a second threshold. In the printing stop process, the second threshold is the number of times that abnormal discharge has occurred since the control unit determined that the life count information became larger than the first reference value as a result of the second determination process. When the control unit determines that the above is the case, printing processing using the drum cartridge is stopped.

According to a seventh aspect of the present application, in the image forming apparatus according to the sixth aspect, the second reference value is larger than the first reference value.

In an eighth aspect of the present application, in the image forming apparatus according to the sixth aspect or the seventh aspect, the control unit determines that the life count information is lower than the first reference value as a result of the second determination process. If the control unit determines that the number of abnormal discharges that have occurred since the control unit determined that the discharge has increased is not equal to or greater than the second threshold, the cleaning request display process is executed.

In a ninth aspect of the present application, in the image forming apparatus according to any one of the first to eighth aspects, the life count information includes: the cumulative number of rotations of the photoconductor drum; or the cumulative number of dots output using the photosensitive drum.

According to the first to ninth aspects of the present application, even if a drum cartridge that has been installed in the main body of another image forming apparatus and has caused abnormal discharge, is installed in the main body of the image forming apparatus. , drum cartridges can be managed appropriately.

According to the first aspect of the present application, even if the drum cartridge reaches the end of its life, it is possible to continue printing as long as the discharge history information does not satisfy a predetermined condition. Further, the control unit reads life count information and discharge history information stored in the drum memory, and stops printing processing using the drum cartridge accordingly. As a result, even if a drum cartridge used in another image forming apparatus is installed, the drum cartridge can be appropriately managed.

According to the third aspect of the present application, if the difference between the life count information when abnormal discharge occurred this time and the life count information when abnormal discharge occurred last time is smaller than a predetermined value, cleaning of the charger is performed. It is highly likely that this has not been done, or even if it has been done, it was not sufficient. In such a case, the user can be prompted to clean the charger.

According to the fourth aspect of the present application, if the difference between the life count information when abnormal discharge occurred this time and the life count information when abnormal discharge occurred last time is a predetermined value or more, cleaning by the user is not performed. It is highly likely that the power was not turned on or the cover was opened or closed for a long time, but that this is a new abnormal discharge. In such a case, the drum cartridge can be appropriately managed by storing information regarding this abnormal discharge in the drum memory as discharge history information.

According to the fifth aspect of the present application, in a situation where the drum cartridge is still being used even though the life count information of the drum cartridge has become larger than the second reference value which is larger than the first reference value, abnormal discharge may occur. If this occurs a number of times equal to or more than one threshold value, printing processing using the drum cartridge can be stopped. Therefore, the drum cartridge can be appropriately managed.

According to the sixth aspect of the present application, in a situation where the drum cartridge is still being used even if the life count information of the drum cartridge becomes larger than the first reference value, abnormal discharge occurs a number of times equal to or more than the second threshold value. In this case, the printing process using the drum cartridge can be stopped. Therefore, the drum cartridge can be appropriately managed.

According to the seventh aspect of the present application, if the drum cartridge is still being used even if the life count information of the drum cartridge becomes significantly larger than the first reference value, a smaller number of abnormal discharges occur. Sometimes the printing process can be stopped.

1 is a schematic diagram of an image forming apparatus. FIG. 1 is a block diagram showing the electrical configuration of an image forming apparatus. 12 is a flowchart showing the flow of processing executed by the control unit when the cover is opened and closed while the power is on. 7 is a flowchart showing the flow of information latch processing in the drum memory executed by the control section. 7 is a flowchart showing the flow of processing executed by the control unit when an error occurs. 6 is a flowchart showing a continuation of the process of FIG. 5. FIG.

Embodiments of the present disclosure will be described below with reference to the accompanying drawings.

<1. Embodiment>
<1-1. About the configuration of the image forming device>
FIG. 1 is a schematic diagram of an image forming apparatus 100. Image forming apparatus 100 is an electrophotographic printer. Examples of the image forming apparatus 100 include a laser printer or an LED printer. As shown in FIG. 1, the image forming apparatus 100 includes a casing 10, four toner cartridges 20, a drum cartridge 30, a control section 80, and a display 90.

The casing 10 has a box-shaped main body frame 11 and a cover 12. The four toner cartridges 20 , the drum cartridge 30 , and the control section 80 are housed in the internal space of the main body frame 11 of the casing 10 . Further, the display 90 is located on the outer surface of the main body frame 11. The main body frame 11 has an opening. The cover 12 is rotatable between a closed position shown by a two-dot chain line in FIG. 1 and an open position shown by a solid line. When the cover 12 is placed in the closed position, the opening of the main body frame 11 is covered by the cover 12. When the cover 12 is placed in the open position, the opening of the main body frame 11 is opened.

The toner cartridge 20 is removably attachable to the drum cartridge 30. The toner cartridge 20 has a housing that can accommodate toner, which is a developer. The four toner cartridges 20 contain toners of different colors (for example, cyan, magenta, yellow, and black). Further, the toner cartridge 20 of this embodiment includes a developing roller 21. The developing roller 21 is a cylindrical member extending along the developing axis. The developing roller 21 is rotatable about the developing shaft. Further, the toner cartridge 20 includes a toner memory 22. The toner memory 22 is a storage medium from which information can be read and written. The toner memory 22 is, for example, a flash ROM or an EEPROM. The toner memory 22 stores, for example, toner identification information that allows identification of each toner cartridge 20 and toner life information that indicates the lifespan of the toner cartridge 20.

The drum cartridge 30 is removably attachable to the main body frame 11. The drum cartridge 30 has four slots 34 corresponding to the four toner cartridges 20. One of the four toner cartridges 20 is inserted into each slot 34.

The drum cartridge 30 includes four photosensitive drums 31, four chargers 32, and a drum memory 33.

A photosensitive drum 31 is provided for each slot 34. The photosensitive drum 31 transfers toner supplied from the toner cartridge 20 onto printing paper. The photosensitive drum 31 has a cylindrical shape extending along the drum axis. The photosensitive drum 31 is rotatable about the drum axis. When the toner cartridge 20 is installed in the drum cartridge 30 , the outer circumferential surface of the photosensitive drum 31 comes into contact with the outer circumferential surface of the developing roller 21 .

A charger 32 is provided for each slot 34. The charger 32 is a device that charges the outer peripheral surface of the photoreceptor drum 31. The charger 32 of this embodiment is a strocolon type charger having a wire and a grid. Note that the "applied voltage" described below is the voltage applied to the wire and the grid. The "detection voltage" described below is a voltage detected from a wire by applying an applied voltage to the wire and the grid. However, instead of the strocolon type charger, the charger 32 may be a charger of another type, such as a charging roller.

The drum memory 33 stores information regarding the drum cartridge 30. Specifically, the drum memory 33 stores drum identification information that can identify each drum cartridge 30, life count information regarding the life of the drum cartridge 30, and discharge history information regarding abnormal discharge of the charger 32 that occurred in the past. , at least remember. The drum identification information is, for example, a serial number. The drum life information is at least one of the cumulative number of rotations of the photosensitive drum 31, the cumulative number of printed sheets using the photosensitive drum 31, and the cumulative number of output dots using the photosensitive drum 31. In this embodiment, these three pieces of information are stored in the drum memory 33 as life count information.

Note that the cumulative number of rotations of the photosensitive drum 31 is the number of rotations calculated by incrementing or decrementing each time printing is performed in one drum cartridge 30 specified by the drum identification information. Further, the cumulative number of printed sheets using the photosensitive drum 31 is the number of printed sheets calculated by incrementing or decrementing each time printing is performed in one drum cartridge 30 specified by the drum identification information. Further, the cumulative number of output dots using the photosensitive drum 31 is the number of output dots calculated by incrementing or decrementing each time printing is performed in one drum cartridge 30 specified by the drum identification information.

The discharge history information is information stored in the drum memory 33 when the occurrence of abnormal discharge is detected by the abnormal discharge detection circuit 84 described later. The discharge history information stores the occurrence of an abnormal discharge and the life count information of the drum cartridge 30 at the time of the occurrence of the abnormal discharge in association with each other.

The control unit 80 includes a processor 81 such as a CPU, a main body memory 82, a voltage application circuit 83, and an abnormal discharge detection circuit 84. The main body memory 82 is a storage medium from which information can be read and written. The main body memory 82 is, for example, a flash ROM or an EEPROM. Note that the main body memory 82 may be located on the control section 80 or outside the control section 80.

The main body memory 82 stores a computer program for controlling the operation of the image forming apparatus 100. The processor 81 executes various processes according to computer programs stored in the main body memory 82. The processor 81 is capable of executing a latch process, a discharge interval determination process, a discharge history information update process, a first determination process, a second determination process, a cleaning request display process, a drum replacement request display process, and a print stop process, which will be described later. .

The voltage application circuit 83 applies an applied voltage to the wire and grid of the charger 32. The abnormal discharge detection circuit 84 detects the occurrence of abnormal discharge based on the current value flowing through the transformer of the voltage application circuit 83. Specifically, the abnormal discharge detection circuit 84 detects that an abnormal discharge has occurred when an overcurrent with a current value equal to or higher than a threshold flows through the transformer of the voltage application circuit 83 that applies voltage to the wire and the grid. . Here, the abnormal discharge is an abnormal discharge such as a spark discharge, which is different from a corona discharge which is a normal discharge.

The display 90 displays information regarding the operation of the image forming apparatus 100, errors (warnings), etc. based on display data received from the control unit 80. Display 90 is electrically connected to control section 80 .

FIG. 2 shows the electrical connections between the control unit 80, the drum memory 33, and the toner memory 22 when the drum cartridge 30 with the toner cartridge 20 attached thereto is attached to the main body frame 11. FIG. 2 also shows the connection between the control unit 80 and the display 90. When the drum cartridge 30 with the toner cartridge 20 attached thereto is attached to the main body frame 11, the drum memory 33 is electrically connected to the control unit 80 via a connector and wiring (not shown). This allows the processor 81 to read information from the drum memory 33 and write information to the drum memory 33. Further, when the drum cartridge 30 with the toner cartridge 20 attached thereto is attached to the main body frame 11, the toner memory 22 is also electrically connected to the control section 80. This allows the processor 81 to read information from the toner memory 22 and write information to the toner memory 22.

The control unit 80 drives a motor (not shown) when executing the printing process. The photosensitive drum 31 and the developing roller 21 are rotated by the driving force of this motor. Further, the control unit 80 applies a voltage to the charger 32. As a result, the surface of the photoreceptor drum 31 is charged. Further, the control unit 80 causes a light source of a light source unit (not shown) to emit light. The light from the light source is irradiated onto the outer peripheral surface of the photoreceptor drum 31 . As a result, an electrostatic latent image of the image to be printed is formed on the outer peripheral surface of the photoreceptor drum 31. The toner in the toner cartridge 20 is supplied onto the electrostatic latent image on the photoreceptor drum 31 via the developing roller 21 . As a result, a toner image is formed on the outer peripheral surface of the photoreceptor drum 31. Thereafter, the printing paper is conveyed between the photosensitive drum 31 and a transfer belt (not shown). As a result, the toner image is transferred from the outer peripheral surface of the photoreceptor drum 31 to the printing paper. With the toner image transferred to the printing paper, the printing paper is conveyed to a fixing unit in the image forming apparatus 100. As a result, the toner image transferred to the printing paper is thermally fixed onto the printing paper. As a result, the image is printed on the printing paper.

<1-2. Regarding processing when turning on the power and opening/closing the cover>
Next, a process executed by the control unit 80 when the cover 12 is opened or closed while the image forming apparatus 100 is powered on will be described with reference to FIGS. 3 and 4.

FIG. 3 is a flowchart showing the process of starting the printing process executed by the control unit 80. As shown in FIG. 3, the control unit 80 determines whether or not the image forming apparatus 100 is powered on (step S1), and determines whether or not the cover 12 of the casing 10 is opened/closed (step S1). Perform S2).

Then, the control unit 80 determines that the cover 12 of the casing 10 has been rotated from the open position to the closed position (step S2: yes) when the image forming apparatus 100 is powered on (step S1: yes). If so, the process moves to the next process, a process of latching information in the drum memory 33 (step S3). In the latch process, the control unit 80 sequentially reads out information stored in the drum memory 33. After the control unit 80 completes the latching process for the information in the drum memory 33 (step S3), the control unit 80 subsequently determines whether a usage prohibition flag, which will be described later, is ON (step S4). Note that the use prohibition flag is information stored in the drum memory 33 in step S49 or S52, which will be described later.

As a result of the control unit 80 determining whether or not the use prohibition flag is ON (step S4), if it is determined that the use prohibition flag is ON (step S4: yes), the control unit 80 performs image formation. The apparatus 100 is placed in a "not Ready" state (print processing is stopped). That is, the control unit 80 puts the image forming apparatus 100 into a state where it does not accept print requests (jobs).

On the other hand, as a result of the control unit 80 determining whether or not the use prohibition flag is ON (step S4), if it is determined that the use prohibition flag is OFF (step S4: no), the control unit 80 The image forming apparatus 100 is placed in a "Ready" state (waiting for an operation request). That is, the control unit 80 puts the image forming apparatus 100 in a state of waiting for a print request, and makes the image forming apparatus 100 standby.

<1-3. About latch processing of information in drum memory>
Next, the latching process (step S3) of information in the drum memory 33 executed by the control section 80 will be described in more detail with reference to FIG. 4. FIG. 4 is a flowchart showing the latching process of information in the drum memory 33 executed by the control section 80.

As shown in FIG. 4, when the latching process of the information in the drum memory 33 is started, the control unit 80 first reads out the cumulative number of prints using the photosensitive drum 31 from the drum memory 33 ( Step S31). Subsequently, the control unit 80 reads the cumulative number of rotations (drum rotation number) of the photosensitive drum 31 from the drum memory 33 (step S32). Subsequently, the control unit 80 reads discharge history information of the charger 32 from the drum memory 33 (step S33). After that, the control unit 80 reads out information regarding whether the use prohibition flag is ON or OFF from the drum memory 33 (step S34).

In the image forming apparatus 100 of the present embodiment, as described above, the control unit 80 controls the printing process based on the information regarding whether the usage prohibition flag read from the drum memory 33 is ON or OFF. It is possible to switch between running and stopping.

<1-4. Regarding processing when an error occurs>
Next, the flow of processing executed when the control unit 80 detects that an error has occurred will be described in detail with reference to FIGS. 5 and 6. FIGS. 5 and 6 are flowcharts showing the processing that the control unit 80 executes when it detects that an error has occurred.

When the control unit 80 detects that an error of some kind has occurred based on a signal from a sensor or the like electrically connected to the control unit 80, the control unit 80 stops the above-mentioned motor and restarts the image forming apparatus. 100 is stopped (step S41).

When the printing process is stopped, the control unit 80 determines whether the error that has occurred is an abnormal discharge based on the detection result of the abnormal discharge detection circuit 84 (step S42). Specifically, the abnormal discharge detection circuit 84 detects the occurrence of abnormal discharge when the current value flowing through the transformer of the voltage application circuit 83 exceeds a threshold value. If the abnormal discharge detection circuit 84 detects abnormal discharge, the control unit 80 determines that the error that has occurred is abnormal discharge. If the abnormal discharge detection circuit 84 does not detect abnormal discharge, the control unit 80 determines that the error that has occurred is an error other than abnormal discharge.

The control unit 80 determines whether the error that has occurred is an abnormal discharge based on the detection result of the abnormal discharge detection circuit 84, and if it is determined that the error that has occurred is an error other than abnormal discharge (step S42). :no), the process moves to step S43. That is, the control unit 80 displays a message on the display 90 according to the type of error that has occurred (step S43).

The control unit 80 determines whether or not the error that has occurred is an abnormal discharge based on the detection result of the abnormal discharge detection circuit 84, and if it is determined that the error that has occurred is an abnormal discharge (step S42: yes). Then, the control unit 80 reads discharge history information from the drum memory 33 (step S44). Further, the control unit 80 reads out the life count information from the drum memory 33 when the current error occurs. Specifically, the control unit 80 controls the cumulative number of rotations of the photoreceptor drum 31, the cumulative number of sheets printed using the photoreceptor drum 31, or the cumulative number of prints using the photoreceptor drum 31 when the current error occurs. The number of output dots is read from the drum memory 33.

After reading the discharge history information from the drum memory 33, the control unit 80 reads the life count information at the time when the current error occurred from the drum memory 33. The control unit 80 compares the life count information at the time when the previous abnormal discharge occurred, which is included in the discharge history information, with the life count information at the time when the current error occurred, read from the drum memory 33. Then, the control unit 80 determines whether the difference between each count value of the cumulative number of rotations, the cumulative number of printed sheets, and the cumulative number of output dots from the previous count value is greater than or equal to a predetermined value determined for each count value. (Step S45: Discharge interval determination process).

As a result of the determination in the discharge interval determination process, the control unit 80 determines that the difference between each count value and the previous count value is smaller than a predetermined value in any of the cumulative number of rotations, the cumulative number of printed sheets, and the cumulative number of output dots. If determined (step S45: no), the process moves to the next step S46 without adding information regarding the current abnormal discharge to the discharge history information stored in the drum memory 33 (step S46: cleaning request display). In this case, since the time interval at which the abnormal discharge occurred is short, it is highly likely that the charger 32 has not been cleaned by the user or has been insufficiently cleaned. Therefore, the control unit 80 does not treat the current abnormal discharge as a newly occurring error.

In the cleaning request display process, the control unit 80 displays a message on the display 90 urging the user to clean the charger 32 (specifically, the wire of the charger 32) (step S46). Further, the control unit 80 may cause the display 90 to display, for example, an illustration showing a method of cleaning the wire.

On the other hand, as a result of the determination in the discharge interval determination process, the control unit 80 determines that the difference between each count value and the previous count value is equal to or greater than a predetermined value in at least one of the cumulative number of rotations, the cumulative number of printed sheets, and the cumulative number of output dots. If it is determined that it is (step S45: yes), the process moves to the next step S47 (step S47: discharge history information update process). In this case, since the time interval at which the abnormal discharge occurred is not short, it is not because the user turned on the power to the image forming apparatus 100 or opened/closed the cover 12 without performing sufficient cleaning, but because the abnormal discharge newly occurred this time. There is a high possibility that there is. Therefore, the control unit 80 causes the drum memory 33 to store information regarding the current abnormal discharge as discharge history information.

In the discharge history information update process, the control unit 80 writes the occurrence of the current abnormal discharge and the life count information at the time of the occurrence of the current abnormal discharge into the drum memory 33 in association with each other (step S47: historical information update processing).

After executing the discharge history information update process, the control unit 80 moves to the first determination process (step S48: first determination process). In the first determination process, the control unit 80 determines that abnormal discharge has occurred after the control unit 80 determines that the life count information read from the drum memory 33 has reached a second reference value that is larger than the first reference value. It is determined whether the number of times detected by the abnormal discharge detection circuit 84 is greater than or equal to a first threshold value. Here, the "first reference value" is a count value corresponding to, for example, the time to replace the drum cartridge 30. The "second reference value" is, for example, a count value that corresponds to twice the replacement time of the drum cartridge 30. Further, the "first threshold" is, for example, once. That is, in the first determination process, even if the life count information of the drum cartridge 30 becomes larger than the second reference value (for example, twice the life), which is larger than the first reference value (for example, the life), the drum cartridge 30 is still detected. The control unit 80 determines whether or not abnormal discharge has occurred a number of times equal to or greater than a first threshold value (for example, once) under a situation where the battery 30 is being used.

As a result of executing the first determination process, abnormal discharge occurs after the control unit 80 determines that the life count information read from the drum memory 33 has reached the second reference value, which is larger than the first reference value. If it is determined that the number of times the abnormal discharge detection circuit 84 detects that the abnormal discharge has occurred is greater than or equal to the first threshold value (step S48: yes), the control unit 80 turns on the use disallowance flag (step S49). That is, in step S49, even if the life count information of the drum cartridge 30 becomes larger than the second reference value (for example, twice the life), which is larger than the first reference value (for example, the life), the drum cartridge is still used. If abnormal discharge occurs for a number of times equal to or more than a first threshold value (for example, once) under a situation where Turn on. Specifically, the control unit 80 writes in the drum memory 33 that the usage prohibition flag is ON.

After executing the process of step S49, the control unit 80 executes a drum replacement request display process. Specifically, the control unit 80 displays on the display 90 a message prompting the user to replace the drum cartridge 30 (step S50: drum replacement request display process). Further, the control unit 80 may cause the display 90 to display, for example, an illustration showing how to replace the drum cartridge 30.

As a result of executing the first determination process, abnormal discharge occurs after the control unit 80 determines that the life count information read from the drum memory 33 has reached the second reference value, which is larger than the first reference value. If it is determined that the number of times the abnormal discharge detection circuit 84 has detected that the abnormal discharge has occurred is smaller than the first threshold value (step S48: no), the control unit 80 subsequently moves to the second determination process.

In the second determination process, the control unit 80 determines that an abnormal discharge has occurred after the control unit 80 determines that the life count information read from the drum memory 33 has become larger than the first reference value. It is determined whether the number of times of detection is equal to or greater than a second threshold (step S48: second determination process). Here, the "first reference value" is, for example, a count value corresponding to the replacement time (life span) of the drum cartridge 30. The "second threshold" is a value larger than the first threshold, and is, for example, twice. That is, in the second determination process, in a situation where the drum cartridge 30 is still being used even if the life count information of the drum cartridge 30 becomes larger than the first reference value (for example, life), the discharge abnormality is determined to be the second one. The control unit 80 determines whether or not this has occurred a number of times equal to or greater than a threshold value (for example, twice).

As a result of executing the second determination process, the abnormal discharge detection circuit determines that an abnormal discharge has occurred after the control unit 80 has determined that the life count information read from the drum memory 33 has reached the first reference value. When it is determined that the number of times detected by 84 is equal to or greater than the second threshold (step S51: yes), the control unit 80 turns on the usage prohibition flag (step S52). That is, in step S52, in a situation where the drum cartridge 30 is still being used even though the life count information of the drum cartridge 30 has become larger than the first reference value (for example, life), abnormal discharge has reached the second threshold (for example, life). If this occurs more than once (for example, twice), the control unit 80 turns on the usage disallowance flag in order to disallow execution of subsequent print processing. Specifically, the control unit 80 writes in the drum memory 33 that the usage prohibition flag is ON.

After executing the process of step S52, the control unit 80 executes a drum replacement request display process. Specifically, the control unit 80 displays on the display 90 a message prompting the user to replace the drum cartridge 30 (step S53: drum replacement request display process). Further, the control unit 80 may cause the display 90 to display, for example, an illustration showing how to replace the drum cartridge 30.

<1-5. Summary＞
As described above, the image forming apparatus 100 of this embodiment includes the drum cartridge 30 and the control section 80. The control unit 80 includes an abnormal discharge detection circuit 84. When the abnormal discharge detection circuit 84 detects the occurrence of abnormal discharge, the control unit determines whether the life count information read from the drum memory 33 is equal to or greater than the first reference value and is included in the discharge history information read from the drum memory 33. If the number of abnormal discharges caused is equal to or greater than a predetermined threshold (step S51: yes), the printing process is stopped. On the other hand, the control unit 80 determines that the life count information read from the drum memory 33 is greater than or equal to the first reference value, and that the number of abnormal discharges included in the discharge history information read from the drum memory 33 is equal to or greater than the predetermined threshold. If it is not the above (step S51: no), print processing is executed. Thereby, even if the drum cartridge 30 reaches the end of its lifespan, it is possible to continue printing as long as the discharge history information does not satisfy a predetermined condition. Further, the control unit 80 reads life count information and discharge history information stored in the drum memory 33 from the drum memory 33, and stops printing processing using the drum cartridge 30 accordingly. As a result, even if a drum cartridge 30 used in another image forming apparatus 100 is installed, the drum cartridge 30 can be appropriately managed.

Further, the image forming apparatus 100 of this embodiment further includes a display 90. When the abnormal discharge detection circuit 84 detects the occurrence of abnormal discharge, the control unit 80 determines the life count information read from the drum memory 33 and the previous time when abnormal discharge occurred included in the discharge history information read from the drum memory 33. A discharge interval determination process is executed to determine whether the difference between the life count information and the life count information is smaller than a predetermined value (step S45). Further, when the difference is determined to be smaller than a predetermined value, the control unit 80 executes a cleaning request display process to display a message prompting cleaning of the charger 32 on the display 90 (step S46). If the difference between the life count information when abnormal discharge occurred this time and the life count information when abnormal discharge occurred last time is smaller than a predetermined value, the charger 32 has not been cleaned or has been cleaned. However, it is likely that it was not enough. In such a case, the user can be prompted to clean the charger 32.

Furthermore, in the image forming apparatus 100 of the present embodiment, the control unit 80 uses the life count information read from the drum memory 33 and the previous abnormal discharge included in the discharge history information read from the drum memory 33 in the discharge interval determination process. If it is determined that the difference between the life count information at the time when the abnormal discharge occurred and the difference is greater than a predetermined value, the fact that an abnormal discharge has occurred and the life count information at the time the abnormal discharge occurred are set as discharge history information. The discharge history information update process stored in the drum memory 33 can be executed (step S47). Here, if the difference between the lifespan count information when abnormal discharge occurred this time and the lifespan count information when abnormal discharge occurred last time is more than a predetermined value, the user may turn on the power or cover the battery with insufficient cleaning. There is a high possibility that the opening/closing operation of No. 12 was not performed, but that this is a new abnormal discharge. In such a case, the drum cartridge 30 can be appropriately managed by storing information regarding this abnormal discharge in the drum memory 33 as discharge history information.

Furthermore, in the image forming apparatus 100 of the present embodiment, the control unit 80 determines that when the discharge history information update process (step S47) is executed, the life count information read from the drum memory 33 is greater than the first reference value. A first determination process for determining whether the number of times the abnormal discharge detection circuit 84 detects that an abnormal discharge has occurred after the controller 80 determines that the discharge has become larger than a second larger reference value is equal to or greater than a first threshold. It is executable (step S48). Further, the control unit 80 detects that an abnormal discharge has occurred after the control unit 80 determines that the life count information has become larger than the second reference value as a result of the determination in the first determination process (step S48). If the control unit 80 determines that the number of times detected by the circuit 84 is equal to or greater than the first threshold, it is possible to execute a print stop process that stops the print process using the drum cartridge 30 (steps S49, S6). . As a result, even if the life count information of the drum cartridge 30 becomes larger than the second reference value (for example, twice the life), which is larger than the first reference value (for example, the life), the drum cartridge is still being used. Below, if abnormal discharge occurs a number of times equal to or greater than a first threshold value (eg, once), the printing process using the drum cartridge 30 can be stopped. Therefore, the drum cartridge 30 can be managed appropriately.

In the image forming apparatus 100 of the present embodiment, the control unit 80 determines that the life count information is larger than the second reference value, which is larger than the first reference value, as a result of the judgment in the first judgment process (step S48). If it is determined that the number of abnormal discharges detected by the abnormal discharge detection circuit 84 after the control unit 80 determined that the abnormal discharge has occurred is not equal to or greater than the first threshold value, the life count information is greater than the first reference value. A second determination process can be executed to determine whether the number of times the abnormal discharge detection circuit 84 has detected that an abnormal discharge has occurred after the control unit 80 determines that the abnormal discharge has occurred is equal to or greater than a second threshold (step S51). The control unit 80 also determines the number of times that abnormal discharge has occurred since the control unit 80 determined that the life count information became larger than the first reference value as a result of the second determination process (step S51). When the control unit 80 determines that the second threshold value is greater than or equal to the second threshold, a print stop process for stopping the print process using the drum cartridge 30 can be executed (steps S52 and S6). As a result, in a situation where the drum cartridge is still being used even if the life count information of the drum cartridge 30 becomes larger than the first reference value (for example, life), abnormal discharge exceeds the second threshold (for example, twice). If this occurs a number of times, the printing process using the drum cartridge 30 can be stopped. Therefore, the drum cartridge 30 can be appropriately managed.

Furthermore, in the image forming apparatus 100 of this embodiment, the second reference value is larger than the first reference value. As a result, if the drum cartridge is still being used even if the life count information of the drum cartridge becomes significantly larger than the first reference value (e.g. lifespan), when a smaller number of abnormal discharges occur, Print processing can be stopped.

<2. Modified example>
Although the exemplary embodiments of the present disclosure have been described above, the present disclosure is not limited to the above embodiments.

In the above embodiment, four toner cartridges 20 are mounted on a common drum cartridge 30. However, instead of the above, a plurality of drum cartridges each having one toner cartridge mounted therein may be mounted in the casing. In this case, the drum cartridge with one toner cartridge installed has one photosensitive drum and one charger.

The discharge history information may accumulate information about all abnormal discharges that occurred in the past, or may sequentially delete old discharge history information.

In the above embodiment, the "second reference value" is, for example, a count value that corresponds to twice the replacement time of the drum cartridge 30. However, the present invention is not limited to this, and the "second reference value" may be a count value that is equal to or more than one time the replacement time of the drum cartridge.

Note that a toner cartridge without a developing roller may be used. In this case, the developing roller may be included in the drum cartridge.

Furthermore, the elements appearing in the above-described embodiments and modified examples may be combined as appropriate to the extent that no contradiction occurs.

10 Casing 11 Body frame 12 Cover 20 Toner cartridge 21 Developing roller 22 Toner memory 30 Drum cartridge 31 Photosensitive drum 32 Charger 33 Drum memory 80 Control section 81 Processor 82 Body memory 83 Voltage application circuit 84 Abnormal discharge detection circuit 90 Display 100 Image forming device

Claims (9)

An image forming apparatus,
a photoreceptor drum;
a charger that charges the surface of the photoreceptor drum;
a drum memory that stores life count information regarding the life of the drum cartridge and discharge history information regarding abnormal discharge of the charger that occurred in the past;
a drum cartridge having;
a control unit capable of executing print processing and stopping print processing;
Equipped with
The control unit includes:
a voltage application circuit that applies voltage to the charger;
an abnormal discharge detection circuit that detects occurrence of abnormal discharge based on the current value of the voltage application circuit;
When the abnormal discharge detection circuit detects the occurrence of the abnormal discharge, the control unit:
If the life count information read from the drum memory is equal to or greater than a first reference value, and the number of abnormal discharges included in the discharge history information read from the drum memory is equal to or greater than a predetermined threshold, stop the printing process,
If the life count information read from the drum memory is equal to or greater than the first reference value, and the number of abnormal discharges included in the discharge history information read from the drum memory is not equal to or greater than the predetermined threshold; An image forming apparatus characterized in that it executes printing processing. The image forming apparatus according to claim 1,
The image forming apparatus is characterized in that the drum memory stores, as the discharge history information, information that abnormal discharge has occurred in the past and the life count information of the drum cartridge at the time when the abnormal discharge occurred. The image forming apparatus according to claim 2 includes:
Equipped with an additional display,
The control unit includes:
When the abnormal discharge detection circuit detects the occurrence of the abnormal discharge, the life count information read from the drum memory and the life count information at the time of the previous abnormal discharge included in the discharge history information read from the drum memory. a discharge interval determination process that determines whether the difference between the life count information and the is smaller than a predetermined value;
cleaning request display processing for displaying a message prompting cleaning of the charger on the display when the difference is determined to be smaller than a predetermined value;
An image forming apparatus characterized in that it is capable of executing. The image forming apparatus according to claim 3,
The control unit includes:
a discharge history in which, when it is determined that the difference is greater than or equal to a predetermined value, the fact that an abnormal discharge has occurred and the life count information at the time when the abnormal discharge occurs are stored in the drum memory as the discharge history information; An image forming apparatus characterized in that it is capable of executing information update processing. The image forming apparatus according to claim 4,
The control unit includes:
When the discharge history information update process is executed,
The abnormal discharge detection circuit detects that an abnormal discharge has occurred after the control unit determines that the life count information read from the drum memory has become larger than a second reference value that is larger than the first reference value. a first determination process that determines whether the number of times that the
As a result of the first determination process, the number of times the abnormal discharge detection circuit detects that an abnormal discharge has occurred after the control unit has determined that the life count information has become larger than the second reference value is determined. a print stop process that stops print processing using the drum cartridge when the control unit determines that the value is equal to or higher than a first threshold;
An image forming apparatus characterized in that it is capable of executing. The image forming apparatus according to claim 5,
The control unit includes:
As a result of the determination in the first determination process, the abnormal discharge is detected when the control unit determines that the life count information has become larger than a second reference value that is larger than the first reference value. If it is determined that the number of times detected by the circuit is not equal to or greater than the first threshold value, it is determined that abnormal discharge has occurred after the controller determines that the life count information has become larger than the first reference value. a second determination process for determining whether the number of times the abnormal discharge has been detected by the abnormal discharge detection circuit is equal to or greater than a second threshold;
As a result of the determination in the second determination process, the control unit determines that the number of abnormal discharges that have occurred since the control unit has determined that the life count information has become larger than the first reference value is equal to or greater than the second threshold value. printing stop processing that stops printing processing using the drum cartridge when it is determined by the department;
An image forming apparatus characterized by being capable of executing. The image forming apparatus according to claim 6,
The image forming apparatus is characterized in that the second reference value is larger than the first reference value. The image forming apparatus according to claim 6 or 7,
The control unit includes:
As a result of the determination in the second determination process, the control unit determines that the number of abnormal discharges that have occurred since the control unit determined that the life count information became larger than the first reference value is not equal to or greater than a second threshold value. An image forming apparatus characterized in that the cleaning request display process is executed when the cleaning request display process is determined. The image forming apparatus according to any one of claims 1 to 8,
The life count information is at least one of the cumulative number of rotations of the photosensitive drum, the cumulative number of printed sheets using the photosensitive drum, and the cumulative number of output dots using the photosensitive drum. image forming apparatus.

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