JP2022157969A - Drum unit and image forming apparatus - Google Patents

Abstract

To optimize the life of a drum unit in accordance with its state of use.SOLUTION: A drum unit 50 comprises: a first photoreceptor drum 51K; a first developing unit 60K; second photoreceptor drums 51Y, 51M, 51C; and second developing units 60Y, 60M, 60C. The first developing unit 60K has a first magnetic roller 61K that supplies a toner in a specific color, a first developer container 62K, and a first conveying member 63K that can convey the toner and carrier toward the first magnetic roller 61K. The second developing units 60Y, 60M, 60C have second magnetic rollers 61Y, 61M, 61C that supply toner other than the specific color, second developer containers 62Y, 62M, 62C, and second conveying members 63Y, 63M, 63C that can convey the toner and carrier toward the second magnetic rollers 61Y, 61M, 61C. The life of the first developing unit 60K is longer than the lives of the second developing units 60Y, 60M, 60C.SELECTED DRAWING: Figure 2

Description

The present disclosure relates to a drum unit and an image forming apparatus to which the drum unit is attached.

2. Description of the Related Art Conventionally, an image forming apparatus is known that includes an apparatus main body, a drum unit, and a toner cartridge (see Patent Document 1). The toner cartridge is detachable from the apparatus main body. The drum unit is detachable from the apparatus main body separately from the toner cartridge. The drum unit has a developer container containing a carrier. The apparatus body includes a toner replenishing device that replenishes the toner in the toner cartridge to the developing container.

JP 2006-171105 A

A drum unit that integrates a plurality of photoreceptor drums and developing units is conceivable in order to eliminate the trouble of separately replacing a plurality of photoreceptor drums and developing units.
However, in a drum unit in which a plurality of photosensitive drums and developing units are integrated, a user who frequently prints in a specific color must replace the drum unit when the developing unit for the specific color reaches the end of its life. For example, a user who frequently uses black-and-white printing must replace the drum unit when the black developing unit reaches the end of its life. In such a case, the drum unit is replaced while the developing units other than the developing unit for the specific color are not so deteriorated.

Therefore, it is an object of the present invention to optimize the life of the drum unit according to the usage conditions by making the life of the developing unit for the specific color different from that of the developing unit for the other colors.

A drum unit for solving the above problems includes a first photoreceptor drum, a first developing unit, a second photoreceptor drum, and a second developing unit.
The first developing unit includes a first magnetic roller that supplies toner of a specific color to the first photosensitive drum, a first developer container that stores a carrier, and a first conveying member positioned inside the first developer container. and a first transport member capable of transporting the toner and carrier toward the first magnetic roller.
The second developing unit includes a second magnetic roller that supplies toner of a color other than a specific color to the second photosensitive drum, a second developer container that stores a carrier, and a second conveying member that is positioned in the second developer container. a second transport member capable of transporting the toner and carrier toward the second magnetic roller;
The life of the first developer unit is longer than the life of the second developer unit.

According to such a configuration, since the life of the first developing unit is longer than that of the second developing unit, the first developing unit corresponding to the toner of the specific color is replaced with the second developing unit corresponding to the toner other than the specific color. It is possible to prevent the drum unit from being replaced in a state where the second developing unit is not so deteriorated even if it is used more. Therefore, the life of the drum unit can be optimized.

Further, in the drum unit described above, the carrier in the first developing container may have a larger filling amount than the carrier in the second developing container.

According to this, the carrier in the first developer container is larger than the carrier in the second developer container, so that the deterioration of the carrier in the first developer container is slower than the deterioration of the carrier in the second developer container. Therefore, the life of the first developing unit can be made longer than the life of the second developing unit.

In the drum unit described above, the carrier in the first developing container may have a thicker coat layer on the surface than the carrier in the second developing container.

According to this, the life of the first developing unit can be made longer than the life of the second developing unit.

Further, in the drum unit described above, the carrier in the first developing container may have a harder coat layer on the surface than the carrier in the second developing container.

According to this, the life of the first developing unit can be made longer than the life of the second developing unit.

Further, in the drum unit described above, the toner of the specific color may have a structure in which the carrier is less abraded than the toner of the other color.

According to this, the life of the first developing unit can be made longer than the life of the second developing unit.

In the drum unit described above, the drum unit includes a first storage area for storing first development life information regarding the life of the first development unit and a second storage area for storing second development life information regarding the life of the second development unit. a first toner sensor capable of outputting a signal corresponding to the toner concentration in the first developing container; a second toner sensor capable of outputting a signal corresponding to the toner concentration in the second developing container; wherein the drum memory includes first control voltage information for generating a control voltage, which is a voltage for controlling the measurement signal of the first toner sensor, and voltage for controlling the measurement signal of the second toner sensor. and the second control voltage information for generating the control voltage that is stored.

According to this, an appropriate voltage can be supplied to the first toner sensor and the second toner sensor.

In the drum unit described above, the first development life information includes the number of rotations of the first magnetic roller, the number of prints printed using the first development unit, and the dot count printed using the first development unit. wherein the second development life information includes the number of rotations of the second magnetic roller, the number of prints printed using the second development unit, and the dot count printed using the second development unit; may be configured to include at least one of

Further, in the drum unit described above, the drum unit may be configured to be attachable to or detachable from the image forming apparatus.

Further, in the drum unit described above, the specific color may be black.

An image forming apparatus for solving the above-described problem is mountable with the above-described drum unit and includes a control section. The control unit executes a reading process, a determination process, and a first process.
The reading process is a process of reading first development life information regarding the life of the first development unit and second development life information regarding the life of the second development unit.
The determination process is a process of determining whether each of the first development unit and the second development unit can be used based on the information read out in the readout process.
In the first processing, when it is determined in the determination processing that either one of the first development unit and the second development unit is not usable, one of the first development unit and the second development unit is not used. , and the other developing unit to form an image.

According to this, when it is determined that one of the first development unit and the second development unit is not usable, image formation is performed using the usable development unit. It is possible to prevent the drum unit from being replaced in a state where the drum unit has not deteriorated so much. Further, even if one of the first developing unit and the second developing unit cannot be used, image formation can be performed without replacing the drum unit, thus reducing the troublesomeness of the user who replaces the drum unit.

Further, in the image forming apparatus described above, when it is determined in the determination process that the second developing unit cannot be used, the control section does not use the second developing unit but uses the first developing unit in the first process. It is also possible to form an image by

According to this, even if the second developing unit corresponding to the toner other than the specific color cannot be used, the image is formed using the first developing unit corresponding to the toner of the specific color without exchanging the drum unit. be able to.

Further, in the image forming apparatus described above, when it is determined in the determination process that the first developing unit cannot be used, the control section does not use the first developing unit but uses the second developing unit in the first process. It is also possible to form an image by

According to this, even if the first developing unit corresponding to the toner of the specific color cannot be used, the image is formed using the second developing unit corresponding to the toner other than the specific color without exchanging the drum unit. be able to.

In addition, the image forming apparatus includes a plurality of second developing units, the plurality of second developing units corresponding to different colors, and the control section controlling the second developing unit instead of the first developing unit in the first process. When using the units to form an image of a specific color, the toner of a plurality of second developing units may be mixed.

According to this, by mixing the toners of the plurality of second developing units, an image of a specific color or a color close to the specific color can be formed instead of the first developing unit without exchanging the drum unit.

Further, the control section may be configured to form an image of a specific color by mixing toners of a plurality of second developing units.

In the image forming apparatus described above, the drum unit includes a first storage area for storing first development life information regarding the life of the first development unit and a second storage area for storing second development life information regarding the life of the second development unit. A drum memory having a storage area may be further provided.

Further, in the image forming apparatus described above, the control section calculates the degree of progress of life of the first developing unit from the first development life information stored in the first storage area, and if the calculated degree of progress of life is equal to or greater than the first threshold, In the case where there is no prohibition of image formation using the first developing unit, notification is made that the drum unit should be replaced, and the calculated degree of progress of life is greater than or equal to the second threshold in which the degree of progress of life has advanced from the first threshold. , the image formation using the first developing unit may be prohibited.

Further, in the image forming apparatus described above, the control unit calculates a life progression degree indicating a progression degree of the life of the first developing unit from the first development life information stored in the first storage area, and calculates the calculated life progression degree. is greater than or equal to the first threshold, not prohibiting image formation using the first developing unit and notifying that the drum unit should be replaced; In this case, an extension acceptance process for accepting an input of an instruction to extend the use of the first developing unit is executed, and in the extension acceptance process, if an instruction to extend the use of the first developing unit is not input, image formation using the first developing unit is performed. is prohibited, and when an instruction to extend the use of the first developing unit is input in the extension acceptance process, the extended use is permitted until the progress of the life of the first developing unit reaches a third threshold larger than the second threshold. may be

Further, in the image forming apparatus described above, the control unit calculates the degree of progress of life of the second developing unit from the second development life information, and if the calculated degree of progress of life is equal to or greater than the fourth threshold value, the second developing unit If the image formation using the second developing unit is not prohibited, and the fact that the drum unit should be replaced is notified, and the calculated life progression is equal to or greater than the fifth threshold, which is larger than the fourth threshold, image formation using the second developing unit is started. It is good also as a structure which prohibits.

Further, in the image forming apparatus described above, the control unit calculates the degree of progress of life of the second developing unit from the second development life information, and if the calculated degree of progress of life is equal to or greater than the fourth threshold value, the second developing unit If the used image formation is not prohibited and the drum unit should be replaced, and the calculated life progress is equal to or greater than the fifth threshold, which is larger than the fourth threshold, it is determined whether to extend the use of the second developing unit. An extension acceptance process for accepting input of an instruction is executed, and if an instruction to extend use of the second developing unit is not input in the extension acceptance process, image formation using the second development unit is prohibited, and in the extension acceptance process, the When an instruction to extend the use of the second developing unit is input, the extended use may be permitted until the progress of the life of the second developing unit reaches a sixth threshold larger than the fifth threshold.

Further, in the image forming apparatus described above, the drum unit further includes a first toner sensor capable of measuring the amount of toner in the first developing container and a second toner sensor capable of measuring the amount of toner in the second developing container. Alternatively, the control section may prohibit image formation using the first developing unit when the amount of toner in the first developing container measured by the first toner sensor is greater than a predetermined value.

According to the present disclosure, it is possible to optimize the life of the drum unit according to the usage conditions by making the life of the developing unit for a specific color different from that of the developing unit for colors other than the specific color.

1 is a sectional view showing a color printer of this embodiment; FIG. FIG. 3 is a cross-sectional view showing a drum unit to which a toner cartridge is attached; FIG. 4 is a cross-sectional view showing a state in which the drum unit is positioned at the pulled-out position; 3A and 3B are perspective views of a developing unit; FIG. 4 is a cross-sectional view of the developing unit; FIG. Conceptual diagram (a) of carrier and toner in the first developing unit, and conceptual diagram (b) of carrier and toner in the second developing unit. 3 is a perspective view of a drum unit; FIG. 3 is a diagram showing electrical connections among a control unit, memories, a temperature/humidity sensor, and a toner sensor; FIG. FIG. 3 is a diagram showing information stored in each storage area of a drum memory and information stored in a toner memory; 6 is a flow chart showing an example of read processing and determination processing executed by a control unit in the first embodiment; 6 is a flowchart showing an example of processing executed by a control unit after a print job is input in the first embodiment; 10 is a flowchart showing an example of read processing and determination processing executed by a control unit in the second embodiment;

Next, the first embodiment of the present disclosure will be described in detail with reference to the drawings as appropriate.
As shown in FIG. 1, a color printer 1 as an example of an image forming apparatus includes an apparatus main body 10, a sheet feeding section 20, an image forming section 30, a discharge section 90, a control section 100, and a temperature/humidity sensor 130. and an operation panel PA.

The device main body 10 has an opening 10A, a front cover 11 and a main body connector 12 . The front cover 11 can move between an open position (see FIG. 3) that opens the opening 10A and a closed position (see FIG. 1) that closes the opening 10A. Specifically, the front cover 11 is rotatable between an open position and a closed position. The body connector 12 is located inside the device body 10 . The body connector 12 is electrically connected to the controller 100 .

The sheet supply section 20 includes a supply tray 21 and a sheet transport mechanism 22 . The supply tray 21 accommodates the sheets S. As shown in FIG. The sheet conveying mechanism 22 conveys the sheet S from the supply tray 21 to the image forming section 30 .

The image forming section 30 includes a scanner unit 40 , a drum unit 50 , a transfer member 70 and a fixing device 80 .

The scanner unit 40 includes a laser emitting section, a polygon mirror, a lens, a reflecting mirror, and the like (not shown). The scanner unit 40 emits a laser beam to the photosensitive drum 51 .

The drum unit 50 is movable in the first direction with respect to the apparatus main body 10 through the opening 10A. Specifically, the drum unit 50 is movable in the first direction with respect to the apparatus main body 10 between an accommodation position where the drum unit 50 is located inside the apparatus main body 10 and a drawn position where the drum unit 50 is pulled out from the apparatus main body 10 . there is That is, the drum unit 50 can be attached to or detached from the color printer 1 .

As shown in FIG. 2, the drum unit 50 includes a plurality of photosensitive drums 51, a plurality of scorotron chargers 52, a plurality of cleaning rollers 53, a sheet guide 54, a connector 55, a plurality of developing units 60, and a drum memory DM.
Further, as shown in FIG. 3, the drum unit 50 can be mounted with or removed from a plurality of toner cartridges TC. Specifically, the toner cartridge TC is attachable or detachable in a direction crossing the axial direction of the photosensitive drum 51 (simply referred to as “axial direction” in the following description). Preferably, the toner cartridge TC is attachable or detachable in a direction perpendicular to the axial direction of the photosensitive drum 51 .

Each photoreceptor drum 51 is rotatable about a first axis X1 extending in the axial direction. The axial direction is a direction intersecting with the first direction. Specifically, the axial direction is a direction perpendicular to the first direction. The four photosensitive drums 51 are arranged in the first direction.

Each scorotron charger 52 is a charger that charges each photosensitive drum 51 . A charging roller may be used instead of the scorotron charger 52 . Each cleaning roller 53 is a roller for cleaning each photosensitive drum 51 . A cleaning blade may be used instead of the cleaning roller 53 .

The sheet guide 54 is a guide that guides the sheet S toward the photosensitive drum 51 . The sheet guide 54 is aligned with the photoreceptor drum 51 in the first direction. The sheet guide 54 is positioned upstream of the four photosensitive drums 51 in the sheet S conveying direction.

A connector 55 is located on the outer surface of the drum unit 50 . Specifically, the connector 55 is located on the outer surface of the frame that supports the developer unit 60 .

In this embodiment, the drum unit 50 includes a first photosensitive drum 51K corresponding to black (K) toner TN as an example of a specific color, and toners other than black (K), namely yellow (Y) and magenta (M). - It has three second photosensitive drums 51Y, 51M, and 51C corresponding to the cyan (C) toner TN. Further, the drum unit 50 is compatible with the first developing unit 60K for black (K) toner and toner TN other than black (K), that is, toner TN for yellow (Y), magenta (M), and cyan (C). and three second developing units 60Y, 60M and 60C.

Each developing unit 60 is arranged in the first direction. Each developing unit 60 is positioned between the corresponding toner cartridge TC and the photosensitive drum 51 . Each developing unit 60 includes a magnetic roller 61 , a developing container 62 , a conveying member 63 and a layer thickness regulating member 65 .

Each magnetic roller 61 is a roller that supplies toner TN to each photosensitive drum 51 . As shown in FIG. 2, each magnetic roller 61 has a magnetic shaft member 611 and a magnetic sleeve 612 . The magnetic shaft member 611 has different magnetic poles arranged in a predetermined pattern in the circumferential direction. The magnetic shaft member 611 is, for example, a cylindrical member in which a plurality of permanent magnets are embedded. The magnetic shaft member 611 is fixed to the developer container 62 .

The magnetic sleeve 612 is made of, for example, a cylindrical member mainly made of non-magnetic metal material. The magnetic sleeve 612 is rotatable around the magnetic shaft member 611 . The magnetic sleeve 612 holds the carrier CR by the magnetic force of the magnetic shaft member 611 . The toner TN and the carrier CR are triboelectrically charged by being agitated in the developing container 62, and the toner TN is electrostatically held by the carrier CR on the magnetic roller 61 (see FIG. 6A).

Each magnetic roller 61 is positioned between each corresponding toner cartridge TC and each photosensitive drum 51 . The magnetic sleeve 612 is rotatable about a second axially extending axis X2. That is, the magnetic roller 61 is rotatable about the axially extending second axis X2. Each magnetic roller 61 faces the surface of each corresponding photosensitive drum 51 . Each magnetic roller 61 is separated from the surface of each corresponding photosensitive drum 51 .

Each developer container 62 is a container that accommodates a magnetic carrier CR. Carrier CR is, for example, iron powder. Each developer container 62 has a supply port 620 . The supply port 620 allows the toner TN to be supplied from the toner cartridge TC. The supply port 620 is located on the side opposite to the magnetic roller 61 with respect to the conveying member 63 .

The supply port 620 is positioned above the conveying member 63 . The second axis X2 is positioned below the conveying member 63 . When the toner cartridge TC is attached to the developing container 62 , the toner TN can be supplied to the developing container 62 from the supply port 620 .

As shown in FIGS. 4A and 4B, the supply port 620 is located at one end of the developer container 62 in the axial direction.

As shown in FIG. 2, the conveying member 63 is positioned inside the developer container 62 . As shown in FIG. 5, the conveying member 63 includes an upstream auger 631 that conveys the carrier CR and the toner TN in the developing container 62 from one end of the developing container 62 in the axial direction toward the other end, and and a downstream auger 632 conveying toward one end. The upstream auger 631 is rotatable about a third axis X3 extending in the second direction. The downstream auger 632 is rotatable about a fourth axis X4 extending in the second direction. Upstream auger 631 is aligned with downstream auger 632 in a first direction. The upstream auger 631 is positioned closer to the replenishment port 620 than the downstream auger 632 .

Each layer thickness regulating member 65 is a member that regulates the thickness of the layer of toner TN on the corresponding magnetic roller 61 . The layer thickness regulating member 65 is out of contact with the magnetic roller 61 . The layer thickness regulating member 65 is positioned below the conveying member 63 .

Each layer thickness regulating member 65 is aligned with the corresponding magnetic roller 61 in the first direction. The second axis X2 is positioned between the layer thickness regulating member 65 and the first axis X1 in the first direction.

The first developing unit 60K includes a first magnetic roller 61K, a first developing container 62K, a first conveying member 63K, a first layer thickness regulating member 65K, and a first toner sensor 66K (see FIG. 4). have.

The first magnetic roller 61K supplies black (K) toner TN to the first photosensitive drum 51K. The first developer container 62K accommodates the carrier CR. The first conveying member 63K is positioned inside the first developer container 62K. The first conveying member 63K can convey the toner TN and the carrier CR toward the first magnetic roller 61K. The first toner sensor 66K can measure the amount of toner in the first developer container 62K (see FIG. 4).

The second developing units 60Y, 60M, 60C include second magnetic rollers 61Y, 61M, 61C, second developing containers 62Y, 62M, 62C, second conveying members 63Y, 63M, 63C, and second layer thickness regulating members. 65Y, 65M, 65C and second toner sensors 66Y, 66M, 66C (see FIG. 4).

The second magnetic rollers 61Y, 61M, and 61C supply toner TN other than black (K), that is, toner TN of yellow (Y), magenta (M), and cyan (C) to the second photosensitive drums 51Y, 51M, and 51C. do. That is, the plurality of second developing units 60Y, 60M, 60C correspond to different colors. The second developer containers 62Y, 62M, 62C accommodate carriers CR. The second conveying members 63Y, 63M, 63C are positioned inside the second developer containers 62Y, 62M, 62C. The second conveying members 63Y, 63M, 63C can convey the toner TN and the carrier CR toward the second magnetic rollers 61Y, 61M, 61C. The second toner sensors 66Y, 66M, 66C are capable of outputting signals corresponding to toner densities in the second developing containers 62Y, 62M, 62C (see FIG. 4).

In this embodiment, the life of the first developing unit 60K is longer than the life of the second developing units 60Y, 60M, 60C. In this embodiment, the carrier CR in the first developer container 62K shown in FIG. 6A has a larger filling amount than the carrier CR in the second developer containers 62Y, 62M, and 62C shown in FIG. 6B.

As shown in FIGS. 4A and 4B, each developing unit 60 has a toner sensor 66, respectively. The toner sensor 66 includes a first toner sensor 66K capable of outputting a signal corresponding to the toner concentration in the first developing container 62K and capable of outputting a signal corresponding to the toner concentration in the second developing containers 62Y, 62M and 62C. It includes three second toner sensors 66Y, 66M, 66C (see FIG. 8).

The toner sensor 66 is located on the opposite side of the supply port 620 in the axial direction. Specifically, the toner sensor 66 is positioned at the other end of the developing container 62 in the axial direction. The other end is the end opposite to the one end of the developer container 62 where the supply port 620 is located in the axial direction.

The toner sensor 66 can output a signal corresponding to the toner density in the developer container 62 . In this embodiment, the toner sensor 66 is a magnetic sensor capable of measuring magnetic permeability. Each toner sensor 66 has a body portion 661 and a measurement portion 662 . As shown in FIG. 5, the body portion 661 is positioned outside the developer container 62 . The measuring portion 662 enters a hole of the developer container 62 and contacts the toner TN and carrier CR in the developer container 62 . The measurement part 662 has a disk shape. The measurement unit 662 measures magnetic permeability. A signal measured by the toner sensor 66 is sent to the controller 100 . Thereby, the controller 100 can determine the amount of toner in the developer container 62 from the signal sent from the toner sensor 66 . In this embodiment, the signal measured by the toner sensor 66 is a voltage value, and when the amount of toner in the developing container 62 changes, the voltage value output from the toner sensor 66 changes.

The developer container 62 has a first storage chamber 621 , a second storage chamber 622 , a partition wall 623 , a supply opening 624 and a recovery opening 625 . The first accommodation chamber 621 is a space that accommodates the upstream auger 631 . The second housing chamber 622 is a space that houses the downstream auger 632 . Toner TN and carrier CR are contained in the first storage chamber 621 and the second storage chamber 622 .

The partition wall 623 is a wall that partitions the first storage chamber 621 and the second storage chamber 622 . The supply opening 624 is located at one end of the partition wall 623 in the axial direction. The supply opening 624 is connected to the first storage chamber 621 and the second storage chamber 622 . The supply opening 624 allows movement of the toner TN and the carrier CR from the first accommodation chamber 621 to the second accommodation chamber 622 .

The recovery opening 625 is located at the other axial end of the partition wall 623 . The collection opening 625 is connected to the first storage chamber 621 and the second storage chamber 622 . The recovery opening 625 allows movement of the toner TN and the carrier CR from the second accommodation chamber 622 to the first accommodation chamber 621 .

The supply port 620 is connected to the first storage chamber 621 . The distance from supply port 620 to supply opening 624 is greater than the distance from supply port 620 to recovery opening 625 .

The upstream auger 631 conveys the toner TN and the carrier CR from one end 601 to the other end 602 of the developing container 62 in the axial direction. Specifically, the upstream auger 631 conveys the toner TN supplied from the supply port 620 to the first storage chamber 621 to the supply opening 624 together with the carrier CR.

The downstream auger 632 conveys the toner TN and the carrier CR from the other end 602 of the developing container 62 in the axial direction toward the one end 601 . Specifically, the downstream auger 632 conveys the toner TN supplied from the supply opening 624 to the second storage chamber 622 toward the other end in the axial direction together with the carrier CR. The toner TN conveyed in the axial direction by the downstream auger 632 adheres to the surface of the magnetic roller 61 due to the magnetic force of the magnetic roller 61 . The toner TN and carrier CR transported to the other end of the developer container 62 by the downstream auger 632 move to the first storage chamber 621 through the recovery opening 625 .

Thus, the upstream auger 631 and the downstream auger 632 can convey the toner TN and the carrier CR from the supply port 620 toward the magnetic roller 61 . Also, the upstream auger 631 and the downstream auger 632 circulate the carrier CR and toner TN in the developing container 62 .

As shown in FIG. 7, the drum unit 50 has a third side plate W3, a fourth side plate W4, a front plate W5, and a rear plate W6. The third side plate W3, the fourth side plate W4, the front plate W5, and the rear plate W6 are an example of a frame that supports the photosensitive drum 51 and the developing unit 60. As shown in FIG. The third side plate W3, the fourth side plate W4, the front plate W5 and the rear plate W6 are made of resin, for example.

Each developing unit 60 is positioned between the third side plate W3 and the fourth side plate W4 in the axial direction. The front plate W5 is positioned at one end of the third side plate W3 and the fourth side plate W4 in the first direction. The rear plate W6 is positioned at the other end in the first direction of the third side plate W3 and the fourth side plate W4.

As shown in FIG. 9, the drum memory DM has a first memory area DM1, a second memory area DM2, a third memory area DM3, a fourth memory area DM4, and a fifth memory area DM5.

The first storage area DM1 stores first development life information regarding the life of the first development unit 60K. The first development life information is at least one of the number of rotations of the first magnetic roller 61K, the number of prints printed using the first development unit 60K, and the dot count printed using the first development unit 60K. including. In this embodiment, the first development life information includes the number of rotations of the first magnetic roller 61K, the number of printed sheets printed using the first developing unit 60K, and the dot count printed using the first developing unit 60K. , is.

The second storage area DM2 stores second development life information regarding the life of the second development units 60Y, 60M, and 60C. The second development life information includes the number of rotations of the second magnetic rollers 61Y, 61M, and 61C, the number of prints printed using the second development units 60Y, 60M, and 60C, and the number of times the second development units 60Y, 60M, and 60C are used. dot count printed using In this embodiment, the first development life information includes the number of rotations of the second magnetic rollers 61Y, 61M, and 61C, the number of prints printed using the second development units 60Y, 60M, and 60C, and the number of prints printed using the second development units 60Y, 60M, and 60C. , 60M, and 60C.

The third storage area DM3 stores first drum life information, which is information about the life of the first photosensitive drum 51K. The first drum life information includes at least the number of rotations of the first photoreceptor drum 51K, the number of prints printed using the first photoreceptor drum 51K, and the dot count printed using the first photoreceptor drum 51K. including one. In this embodiment, the first drum life information includes the number of rotations of the first photoreceptor drum 51K, the number of prints printed using the first photoreceptor drum 51K, and the number of prints printed using the first photoreceptor drum 51K. dot count.

The fourth memory area DM4 stores second drum life information, which is information about the life of the second photosensitive drums 51Y, 51M, and 51C. The second drum life information includes the number of rotations of the second photoreceptor drums 51Y, 51M, 51C, the number of prints printed using the second photoreceptor drums 51Y, 51M, 51C, and the 51C printed dot count. In this embodiment, the first drum life information includes the number of rotations of the second photoreceptor drums 51Y, 51M, and 51C, the number of prints printed using the second photoreceptor drums 51Y, 51M, and 51C, and the number of times the second photoreceptor drums Dot count printed using drums 51Y, 51M, and 51C.

The fifth memory area DM5 stores the serial number, the history of the number of days used, the history of the temperature and humidity sensor, the drum component information (each color) of the photosensitive drum 51, the carrier CR component information, and the voltage for controlling the measurement signal of the first toner sensor 66K. and a second control voltage for generating the control voltage for controlling the measurement signals of the second toner sensors 66Y, 66M, and 66C. Information (Y, M, C) and job information are stored.

As shown in FIG. 3, the toner cartridge TC contains toner TN, which is a non-magnetic material. In this embodiment, the toner cartridges TC include a first toner cartridge TCK corresponding to black (K) toner TN, and three toner cartridges TCK corresponding to yellow (Y), magenta (M), and cyan (C) toner TN. 2 toner cartridges TCY, TCM, TCC.

Each toner cartridge TC has a toner memory TM. In this embodiment, the toner memory TM includes a first toner memory TMK corresponding to the first toner cartridge TCK, and second toner memories TMY, TMM, and TMC corresponding to the three second toner cartridges TCY, TCM, and TCC. .

As shown in FIG. 9, the first toner memory TMK stores first toner life information, which is information regarding the life of the first toner cartridge TCK. The first toner life information includes replenishment time during which the black toner TN is replenished from the first toner cartridge TCK to the first developer container 62K. In this embodiment, the first toner memory TMK stores a serial number, color information (K), toner supply time, and job information.

The second toner memories TMY, TMM, TMC store second toner life information, which is information about the life of the second toner cartridges TCY, TCY, TCM, TCC. The second toner life information includes replenishment times during which toner TN of corresponding colors is replenished from the second toner cartridges TCY, TCM, and TCC to the second developer containers 62Y, 62M, and 62C. In this embodiment, the second toner memories TMY, TMM, and TMC store serial numbers, color information (Y), (M), and (C), toner supply time, and job information.

As shown in FIG. 1, the transfer member 70 is a member that transfers the toner image on the photosensitive drum 51 onto the sheet S. As shown in FIG. The transfer member 70 is positioned between the sheet supply section 20 and the drum unit 50 . The transfer member 70 includes a driving roller 71 , a driven roller 72 , a conveying belt 73 and a transfer roller 74 .

The driving roller 71 and the driven roller 72 are spaced apart in the first direction. The driving roller 71 and the driven roller 72 support a conveying belt 73 that is an endless belt. The transfer roller 74 is positioned inside the transport belt 73 . The transfer roller 74 sandwiches the conveying belt 73 with the photosensitive drum 51 .

The fixing device 80 has a heating roller 81 and a pressure roller 82 . The pressure roller 82 sandwiches the sheet S with the heat roller 81 .

In the image forming section 30 , the scorotron charger 52 charges the surface of the photosensitive drum 51 . After that, the scanner unit 40 exposes the surface of the photosensitive drum 51 . Thereby, an electrostatic latent image is formed on the photosensitive drum 51 .

The toner cartridge TC replenishes the developer container 62 with toner TN. The upstream auger 631 conveys the toner TN and carrier CR in the developing container 62 to the downstream auger 632 . The downstream auger 632 supplies toner TN to the electrostatic latent image on the photoreceptor drum 51 . Thereby, a toner image is formed on the photosensitive drum 51 .

The conveying belt 73 conveys the sheet S. As shown in FIG. The sheet S passes between the photosensitive drum 51 and the transfer roller 74 . At this time, the toner image on the photosensitive drum 51 is transferred to the sheet S. As shown in FIG. After that, the sheet S passes between the heating roller 81 and the pressure roller 82 . At this time, the toner image on the sheet S is thermally fixed.

The discharge section 90 includes a plurality of conveying rollers 91 . A conveying roller 91 discharges the sheet S to the outside of the apparatus main body 10 .

The control unit 100 includes, for example, a CPU (Central Processing Unit), a RAM (Random Access Memory), a ROM (Read only Memory), and an input/output circuit, and receives information on the mounted cartridge and programs or programs stored in the ROM. The color printer 1 is controlled by performing arithmetic processing based on data.

As shown in FIG. 8 , when the drum unit 50 is attached to the apparatus main body 10 , the control section 100 communicates with each member of the drum unit 50 to control each member of the drum unit 50 .

The color printer 1 includes a main body memory 110 and a control voltage generator 120 in addition to the controller 100 described above. Control unit 100, main memory 110 and control voltage generator 120 are located on a main substrate (not shown).

A plurality of control voltage generators 120 are provided corresponding to the plurality of toner sensors 66K, 66Y, 66M, and 66C. Control voltage generator 120 transforms the input voltage to generate a control voltage for controlling the measurement signal of toner sensor 66 . In this embodiment, the control voltage generator 120 is controlled by the controller 100, transforms the input voltage of 24V, and generates voltages suitable for the toner sensors 66K, 66Y, 66M, and 66C. In this embodiment, the voltage suitable for each of the toner sensors 66K, 66Y, 66M, and 66C is the voltage at which the amount of change in the voltage value output from the toner sensor 66 increases when the amount of toner changes. For example, the control voltage generation unit 120 is a switching regulator, which converts an input DC voltage into a pulse voltage by PWM control and smoothes the pulse voltage to convert it into a predetermined DC voltage.

The control voltage information is information for generating a control voltage, and in this embodiment, is a voltage value for controlling the measurement signal of the toner sensor 66 as an example. The toner sensor 66 has a different appropriate control voltage for each type of toner TN to be measured, for example, each toner TN having a different color. In addition, the appropriate control voltage varies depending on product variations of the toner sensor 66 . The toner sensor 66 may be able to measure the amount of toner in the developing container 62 even if the control voltage is not appropriate. In this embodiment, the control voltage information is measured when the drum unit 50 is manufactured and stored in advance in the drum memory DM.

The control section 100 reads the control voltage information from the drum memory DM and causes the control voltage generation section 120 to generate the control voltage based on the read control voltage information. The controller 100 supplies the generated control voltages to the toner sensors 66K, 66Y, 66M and 66C.
Control unit 100 receives measurement signals measured by toner sensors 66K, 66Y, 66M, and 66C, and calculates toner amounts in developing containers 62K, 62Y, 62M, and 62C from the measurement signals.

The operation panel PA is located on the outer surface of the device body 10 . Operation panel PA is electrically connected to control unit 100 . The operation panel PA displays various messages and confirmation screens based on commands from the control unit 100, and receives instructions from the user. The temperature/humidity sensor 130 can measure temperature and humidity. Data measured by the temperature/humidity sensor 130 is sent to the control unit 100 .

Next, processing executed by the controller 100 after the drum unit 50 is attached to the color printer 1 will be described.

Every time the drum unit 50 is used to form an image, the control section 100 updates the first development life information and the second development life information and writes them in the drum memory DM.
Further, the control unit 100 updates the first drum life information and the second drum life information and writes them in the drum memory DM every time image formation is performed using the drum unit 50 .
Further, the control unit 100 updates the first toner life information and the second toner life information and writes them to the toner memory TM every time image formation is performed using the toner cartridge TC.

After the drum unit 50 is attached to the color printer 1, the controller 100 repeatedly executes the reading process, the determination process, and the first process.

The reading process is a process of reading first development life information regarding the life of the first development unit 60K and second development life information regarding the life of the second development units 60Y, 60M and 60C.

The determination process is a process of determining whether the first development unit 60K and the second development units 60Y, 60M, 60C are usable based on the information read out in the readout process.

First, the determination processing of the first developing unit 60K will be described.
The control section 100 calculates the progress of the life of the first developing unit 60K from the first development life information stored in the first storage area DM1. The progress of life increases as the photoreceptor drum 81 is used, and indicates the progress of the life of the photoreceptor drum 81 . In this embodiment, the control section 100 calculates the progress of life of the first developing unit 60K from the number of rotations of the first magnetic roller 61K.

When the calculated life progress of the first developing unit 60K is equal to or greater than the first threshold, the control unit 100 does not prohibit image formation using the first developing unit 60K and notifies that the drum unit 50 should be replaced. . In this case, the controller 100 can continue image formation using the first developing unit 60K.

When the calculated degree of life progression is equal to or greater than the second threshold, which is larger than the first threshold, the control unit 100 executes extension acceptance processing for accepting input of an instruction to extend the use of the first developing unit 60K. Specifically, the control section 100 displays a message asking the user whether the extended use of the first developing unit 60K is permitted. Based on the message, the user inputs an instruction as to whether or not to extend the use. The control unit 100 accepts an instruction as to whether or not to extend use.

Control section 100 prohibits image formation using first developing unit 60K when an instruction to extend use of first developing unit 60K is not input in the extension acceptance process.
When an instruction to extend the use of the first developing unit 60K is input in the extension acceptance process, the control unit 100 continues the extended use until the degree of progress of the life of the first developing unit 60K reaches a third threshold larger than the second threshold. To give permission.

The controller 100 prohibits image formation using the first developing unit 60K when the calculated degree of progress of life is greater than or equal to a third threshold that is larger than the second threshold.

First, the determination processing of the second developing units 60Y, 60M, 60C will be described.
The control section 100 calculates the progress of life of the second developing units 60Y, 60M, and 60C from the second development life information. In this embodiment, the control section 100 calculates the progress of life of the second developing units 60Y, 60M, 60C from the number of rotations of the second magnetic rollers 61Y, 61M, 61C.

When the calculated life progress of the second developing units 60Y, 60M, and 60C is equal to or greater than the fourth threshold value, the controller 100 does not prohibit image formation using the second developing units 60Y, 60M, and 60C. should be replaced. In this case, the control section 100 can continue image formation using the second developing units 60Y, 60M, and 60C according to the user's instruction.

When the calculated degree of life progression is equal to or greater than a fifth threshold, which is larger than the fourth threshold, the control section 100 executes an extension acceptance process for accepting input of an instruction to extend the use of the second developing units 60Y, 60M, and 60C. . Specifically, the control section 100 displays a message asking the user whether the extended use of the second developing units 60Y, 60M, and 60C is allowed. Based on the message, the user inputs an instruction as to whether or not to extend the use. The control unit 100 accepts an instruction as to whether or not to extend use.

Control section 100 prohibits image formation using second developing units 60Y, 60M, and 60C when an instruction to extend use of second developing units 60Y, 60M, and 60C is not input in the extension acceptance process.
In the extension acceptance process, when an instruction to extend the use of the second developing units 60Y, 60M, 60C is input, the controller 100 determines that the degree of life progress of the second developing units 60Y, 60M, 60C is greater than the fifth threshold. 6 Allow extended use until threshold is reached.

If the calculated degree of progress of life is equal to or greater than a sixth threshold, which is greater than the fifth threshold, the controller 100 prohibits image formation using the second developing units 60Y, 60M, and 60C.

Next, processing executed by the control unit 100 based on the determination processing will be described. When a print job is input, the control unit 100 determines whether image formation can be executed based on determination processing.

When the control section 100 determines in the determination process that both the first developing unit 60K and the second developing units 60Y, 60M, 60C can be used, normal image formation is performed.

When the control section 100 determines in the determination process that both the first developing unit 60K and the second developing units 60Y, 60M, and 60C are unusable, it notifies that the drum unit 50 should be replaced. In this case, the control unit 100 does not perform image formation.

If the control section 100 determines in the determination process that one of the first developing unit 60K and the second developing units 60Y, 60M, 60C is not usable, it executes the first process. In the first process, when it is determined in the determination process that one of the first developing unit 60K and the second developing units 60Y, 60M, 60C is not usable, the first developing unit 60K and the second developing units 60Y, 60M , 60C without using one developing unit 60 and using the other developing unit 60 to form an image.

Specifically, when the controller 100 determines in the determination process that the second developing units 60Y, 60M, and 60C cannot be used, in the first process, the second developing units 60Y, 60M, and 60C are not used, and the second developing units 60Y, 60M, and 60C are not used. An image is formed using one developer unit 60K.
In this case, if the input job is monochrome printing, the control unit 100 executes monochrome printing. However, if the input job is color printing, color printing cannot be performed. display a message asking if it is okay to print in black-and-white printing. Then, when the user inputs an instruction that monochrome printing may be performed, the control unit 100 executes monochrome printing.

On the other hand, when the control section 100 determines in the determination process that the first developing unit 60K cannot be used, in the first process, the first developing unit 60K is not used, and the second developing units 60Y, 60M, and 60C are used. to form an image.
In this case, in the first process, when the second developing units 60Y, 60M, and 60C are used instead of the first developing unit 60K to form a black image, the control section 100 controls the plurality of second developing units 60Y, 60M, and 60C. Toners TN of 60M and 60C are mixed. The control unit 100 uses yellow (Y), magenta (M), and cyan (C) toner TN in a mixed color instead of black toner TN. Show executable. Then, when an instruction to execute YMC mixed gray printing is input, the control unit 100 executes image formation.
When expressing black by mixing toner TN of yellow (Y), magenta (M), and cyan (C), although it is close to black, it may not be completely black. calling.

The controller 100 prohibits image formation using the first developing unit 60K when the amount of toner in the first developing container 62K measured by the first toner sensor 66K is greater than a predetermined value.
If the amount of toner in the second developing containers 62Y, 62M, 62C measured by the second toner sensors 66Y, 66M, 66C is larger than a predetermined value, the control section 100 controls the image processing using the second developing units 60Y, 60M, 60C. Prohibit formation.

Next, an example of read processing and determination processing executed by the control unit 100 in the first embodiment will be described with reference to the flowchart of FIG. In the reading process and determination process, the process for the first developing unit 60K and the process for the second developing units 60Y, 60M, and 60C are almost the same. A description of the processing for the developing units 60Y, 60M, and 60C is omitted. Regarding the processing for the second developing units 60Y, 60M, and 60C, the first threshold in step S3 is the fourth threshold, the second threshold in step S5 is the fifth threshold, and the third threshold in step S6 is the sixth threshold. Just do it.

As shown in FIG. 10, the control unit 100 reads the first development life information from the drum memory DM as a read process (S1).

After step S1, the control section 100 calculates the progress of life of the first developing unit 60K (S2).

After step S2, the controller 100 determines whether or not the life progress of the first developing unit 60K is greater than or equal to the first threshold (S3).

In step S3, if the controller 100 does not determine that the life progress of the first developing unit 60K is equal to or greater than the first threshold value (S3, No), the first developing unit 60K can be used. exit.

In step S3, when the controller 100 determines that the progress of life of the first developing unit 60K is greater than or equal to the first threshold value (S3, Yes), it notifies that the drum unit 50 should be replaced (S4). It is determined whether or not the degree of progress of the life of one developing unit 60K is equal to or greater than the second threshold (S5).

In step S5, if the controller 100 does not determine that the life progress of the first developing unit 60K is equal to or greater than the second threshold value (S5, No), the first developing unit 60K can be used, so the processing is performed. exit.

In step S5, when the controller 100 determines that the degree of progress of life of the first developing unit 60K is equal to or greater than the second threshold (S5, Yes), the degree of progress of life of the first developing unit 60K is equal to or greater than the third threshold. It is determined whether there is (S6).

In step S6, when the controller 100 determines that the life progress of the first developing unit 60K is equal to or greater than the third threshold value (S6, Yes), the first developing unit 60K cannot be used. A flag is set to prohibit image formation using 60K (S10), and the process ends. The control section 100 causes the drum memory DM or the body memory 110 to store a flag for prohibiting image formation using the first developing unit 60K.

In step S6, if the controller 100 does not determine that the life progress of the first developing unit 60K is equal to or greater than the third threshold value (S6, No), it confirms whether to extend the use of the operation panel PA. A confirmation screen is displayed (S7). In this case, the extended use may cause the color printer 1 to be in a situation that would not occur in normal use. is available, but would you like to extend it?" is displayed.

After step S7, the control unit 100 determines whether the user has confirmed the extended use (S8).

In step S8, if the control section 100 does not determine that the user has confirmed the extension of use (S8, No), the control section 100 raises a flag prohibiting image formation using the first developing unit 60K. (S10), the process ends. The control section 100 causes the drum memory DM or the body memory 110 to store a flag for prohibiting image formation using the first developing unit 60K.

In step S8, if the control unit 100 determines that the user has confirmed the extended use (S8, Yes), it sets a flag indicating extended use (S9), and ends the process.

Next, an example of processing executed by the control unit 100 after a print job is input will be described with reference to the flowchart of FIG. 11 .

As shown in FIG. 11, the control unit 100 determines whether there is a print job (S21). If the control unit 100 does not determine that there is a print job (S21, No), it waits until a print job is input.

In step S21, when the control section 100 determines that there is a print job (S21, Yes), it determines whether the first developing unit 60K is usable (S22). The control section 100 determines that the first developing unit 60K can be used when the flag for prohibiting image formation using the first developing unit 60K is not set in the drum memory DM or the main body memory 110 . On the other hand, if a flag prohibiting image formation using the first developing unit 60K is set in the drum memory DM or the main body memory 110, the control section 100 does not determine that the first developing unit 60K can be used.

In step S22, when the control section 100 determines that the first developing unit 60K can be used (S22, Yes), it determines whether the input print job is monochrome printing (S23).

In step S23, when the control unit 100 determines that the input print job is monochrome printing (S23, Yes), normal printing is performed (S28).

In step S23, if the control unit 100 does not determine that the input print job is for monochrome printing (S23, No), that is, if the print job is for color printing, the second developing units 60Y and 60M , 60C are available (S24). If a flag prohibiting image formation using the second developing units 60Y, 60M, and 60C is not set in the drum memory DM or the main body memory 110, the controller 100 does not allow the second developing units 60Y, 60M, and 60C to be used. Determine that it is possible. On the other hand, if a flag prohibiting image formation using the second developing units 60Y, 60M, and 60C is set in the drum memory DM or the main body memory 110, the controller 100 controls the second developing units 60Y, 60M, and 60C. is not considered usable.

In step S24, when the control section 100 determines that all of the second developing units 60Y, 60M, and 60C can be used (S24, Yes), normal printing is executed (S28).

In step S24, if the controller 100 does not determine that the second developing units 60Y, 60M, and 60C are all usable (S24, No), the drum unit 50 should be replaced on the operation panel PA. It is displayed that only printing can be executed (S25).

After step S25, the control unit 100 determines whether the user has consented to executing monochrome printing (S26).

In step S26, when the control section 100 determines that the user has consented to the monochrome printing (S26, Yes), the monochrome printing is performed using the first developing unit 60K (S27).

In step S26, if the control unit 100 does not determine that the user has consented to executing monochrome printing (S26, No), the process ends without executing printing.

In step S22, if the control section 100 does not determine that the first developing unit 60K is usable (S22, No), it determines whether all of the second developing units 60Y, 60M, and 60C are usable (S31 ).

In step S31, if the control section 100 does not determine that the second developing units 60Y, 60M, 60C are all usable (S31, No), the first developing unit 60K and the second developing units 60Y, 60M, 60C cannot be used, a message indicating that the drum unit 50 should be replaced is displayed on the operation panel PA (S35), and the process ends.

In step S31, when the controller 100 determines that the second developing units 60Y, 60M, and 60C are all usable (S31, Yes), the control panel PA instructs the operation panel PA to replace the drum unit 50, is displayed (S32). Note that YMC mixed gray here means monochrome printing by YMC mixed colors when the print job is monochrome, and means color printing in which the black part is represented by YMC mixed colors when the print job is color.

After step S32, the control unit 100 determines whether or not the user has consented to printing in YMC mixed gray (S33).

In step S33, when the control unit 100 determines that the user approves the execution of YMC-mixed gray printing (S33, Yes), it executes YMC-mixed gray printing (S34).

In step S33, if the control unit 100 does not determine that the user has consented to printing in YMC mixed gray (S33, No), the process ends without printing.

According to this embodiment described above, the following effects can be obtained.
In a drum unit in which a developing unit for a specific color and a developing unit for a color other than the specific color are integrated, a user who frequently uses monochrome printing has to replace the drum unit when the developing unit for the specific color reaches the end of its life. In such a case, the drum unit is replaced even if the developing units other than the developing unit for the specific color are not so deteriorated.
However, according to the drum unit 50 of the present disclosure, the life of the first developing unit 60K is longer than the life of the second developing units 60Y, 60M, and 60C. Even if the unit 60K is used more than the second developing units 60Y, 60M, and 60C corresponding to the toner TN other than black, the drum unit 50 is replaced in a state where the second developing units 60Y, 60M, and 60C are not so deteriorated. It is possible to suppress As described above, according to the drum unit 50 of the present disclosure, the life of the developing unit for the specific color and the developing unit for the colors other than the specific color are made different, so that the life of the drum unit can be optimized according to the usage conditions. .

Also, the carrier CR in the first developer container 62K has a larger filling amount than the carrier CR in the second developer containers 62Y, 62M, and 62C. Therefore, even if the same amount of toner TN is supplied, the deterioration of the carrier CR in the first developing container 62K is slower than the deterioration of the carrier CR in the second developing containers 62Y, 62M and 62C. As a result, the life of the first developing unit 60K can be longer than the life of the second developing units 60Y, 60M, 60C.
The life of the developing unit 60 is not determined only by the deterioration of the carrier CR. Since it progresses faster than the members, deterioration of the carrier CR often determines the life of the developing unit 60 .

Also, the drum memory DM stores first control voltage information and second control voltage information. Therefore, the controller 100 can supply appropriate voltages to the first toner sensor 66K and the second toner sensors 66Y, 66M, 66C based on the stored first control voltage information and second control voltage information.

Further, when the control section 100 of the color printer 1 determines that one of the first developing unit 60K and the second developing units 60Y, 60M, and 60C is not usable, the usable developing unit 60 is used for image processing. Carry out formation. Therefore, it is possible to prevent the drum unit 50 from being replaced when one of the plurality of developing units 60 is not so deteriorated. As a result, it is possible to optimize the life of the drum unit according to the conditions of use.

Further, when the second developing units 60Y, 60M, and 60C corresponding to toner TN other than black as an example of a specific color cannot be used, the control unit 100 of the color printer 1 controls the first developing unit corresponding to black toner TN. Since an image is formed using the 60K, it is possible to prevent the drum unit 50 from being replaced when the first developing unit 60K is not so deteriorated. As a result, it is possible to optimize the life of the drum unit according to the conditions of use.

Further, when the first developing unit 60K corresponding to black toner TN as an example of a specific color cannot be used, an image is formed using the second developing units 60Y, 60M, 60C corresponding to toner TN other than black. Therefore, it is possible to prevent the drum unit 50 from being replaced when the second developing units 60Y, 60M, and 60C are not so deteriorated. As a result, it is possible to optimize the life of the drum unit according to the conditions of use.

Further, in the first process, when the second developing units 60Y, 60M, 60C are used instead of the first developing unit 60K to form a black image, the control section 100 controls the plurality of second developing units 60Y, 60M. , 60C of toner TN. Therefore, instead of the first developing unit 60K, a plurality of second developing units 60Y, 60M, and 60C can form a black or near-black image.

In a drum unit that integrates a developing unit for black and a developing unit for colors other than black, users who frequently use monochrome printing must replace the drum unit when the black developing unit reaches the end of its life. In such a case, the drum unit is replaced even if the developing unit for colors other than black is not so deteriorated.
However, according to the drum unit 50 of the present disclosure, the life of the first developing unit 60K is longer than the life of the second developing units 60Y, 60M, and 60C. Even if the second developing units 60Y, 60M, 60C corresponding to the toner TN are used more than the second developing units 60Y, 60M, 60C, it is possible to prevent the drum unit 50 from being replaced in a state where the second developing units 60Y, 60M, 60C are not so deteriorated. .

Also, the carrier CR in the first developer container 62K has a larger filling amount than the carrier CR in the second developer containers 62Y, 62M, and 62C. Therefore, even if the same amount of toner TN is supplied, the deterioration of the carrier CR in the first developing container 62K is slower than the deterioration of the carrier CR in the second developing containers 62Y, 62M and 62C. As a result, the life of the first developing unit 60K can be longer than the life of the second developing units 60Y, 60M, 60C.
The life of the developing unit 60 is not determined only by the deterioration of the carrier CR. Since it progresses faster than the members, deterioration of the carrier CR often determines the life of the developing unit 60 .

Also, the drum memory DM stores first control voltage information and second control voltage information. Therefore, the controller 100 can supply appropriate voltages to the first toner sensor 66K and the second toner sensors 66Y, 66M, 66C based on the stored first control voltage information and second control voltage information.

Further, when the control section 100 of the color printer 1 determines that one of the first developing unit 60K and the second developing units 60Y, 60M, and 60C is not usable, the usable developing unit 60 is used for image processing. Carry out formation. Therefore, it is possible to prevent the drum unit 50 from being replaced when one of the plurality of developing units 60 is not so deteriorated. In addition, even if one of the first developing unit 60K and the second developing units 60Y, 60M, and 60C cannot be used, image formation can be performed without replacing the drum unit 50. can reduce the annoyance of

Further, when the second developing units 60Y, 60M, and 60C, which are compatible with toner TN other than black, cannot be used, the control unit 100 of the color printer 1 uses the first developing unit 60K, which is compatible with black toner TN, to print an image. is formed, it is possible to prevent the drum unit 50 from being replaced when the first developing unit 60K has not deteriorated so much. Further, even when the second developing units 60Y, 60M, 60C cannot be used, monochrome image formation can be performed without replacing the drum unit 50, so the user's trouble of replacing the drum unit 50 can be reduced.

Further, when the first developing unit 60K corresponding to black toner TN cannot be used, the second developing units 60Y, 60M, and 60C corresponding to non-black toner TN are used to form images. It is possible to prevent the drum unit 50 from being replaced when 60Y, 60M, and 60C are not so deteriorated. In addition, even when the first developing unit 60K is not usable, image formation can be performed without replacing the drum unit 50, so that the user's trouble of replacing the drum unit 50 can be reduced.

The drum unit 50 of the present disclosure includes multiple photoreceptor drums 51 and multiple developing units 60 .
For example, in a conventional drum unit, if the drum unit is removed from the image forming apparatus before the end of its life, and then another drum unit is used and then the image forming apparatus is mounted again, the life of the drum unit should be properly managed. could not go to
However, according to the drum unit 50 of the present disclosure, the drum memory DM of the drum unit 50 includes the first storage area DM1 for storing the first development life information, which is information regarding the life of the first development unit 60K, and the second development unit 60Y. , 60M, and 60C, and a second memory area DM2 for storing second development life information, which is information about the life of 60M and 60C. Therefore, even when the drum unit 50 is replaced with another drum unit, the life of the drum unit 50 can be properly managed based on the information stored in the drum memory DM.
The drum memory DM includes a third storage area DM3 for storing first drum life information, which is information about the life of the first photosensitive drum 51K, and information about the life of the second photosensitive drums 51Y, 51M, and 51C. and a fourth memory area DM4 for storing second drum life information. Therefore, even when the drum unit 50 is replaced with another drum unit, the life of the drum unit 50 can be properly managed based on the information stored in the drum memory DM.

The drum memory DM also has a fifth storage area DM5 in which the first control voltage information and the second control voltage information are stored. Therefore, the controller 100 can supply appropriate voltages to the first toner sensor 66K and the second toner sensors 66Y, 66M, 66C based on the stored first control voltage information and second control voltage information.

Further, the first toner cartridge TCK capable of supplying toner to the first developing container 62K has a first toner memory TMK in which first toner life information is stored. The second toner cartridges TCY, TCM, TCC capable of supplying toner to the second developer containers 62Y, 62M, 62C have second toner memories TMY, TMM, TMC in which second toner life information is stored. Therefore, even if the toner cartridge is replaced with another toner cartridge, the life of the toner cartridge TC can be properly managed.

Next, a second embodiment will be described.

In the first embodiment described above, in the determination process, if the calculated degree of progression of the life of the first developing unit 60K is equal to or greater than the second threshold, the controller 100 inputs an instruction to extend the use of the first developing unit 60K. In the second embodiment, when the calculated life progress of the first developing unit 60K is equal to or greater than the second threshold value, the extension acceptance process is not executed. Prohibit image formation using the developing unit 60K.

Specifically, in the determination processing of the first developing unit 60K in the second embodiment, the control unit 100 first determines the degree of progress of the life of the first developing unit 60K from the first development life information stored in the first storage area DM1. Calculate
When the calculated degree of progress of life is equal to or greater than the first threshold, it is notified that the drum unit 50 should be replaced without prohibiting image formation using the first developing unit 60K.
If the calculated degree of progress of life is greater than or equal to the second threshold, i.e., the degree of progress of life is greater than the first threshold, image formation using the first developing unit 50K is prohibited.

Similarly, in the determination processing of the second developing units 60Y, 60M, 60C in the second embodiment, the control section 100 calculates the degree of progress of the life of the second developing units 60Y, 60M, 60C from the second development life information.
When the calculated degree of progress of life is equal to or greater than the fourth threshold, image formation using the second developing units 60Y, 60M, and 60C is not prohibited, and it is notified that the drum unit 50 should be replaced.
If the calculated life progress is equal to or greater than the fifth threshold, which is greater than the fourth threshold, image formation using the second developing units 60Y, 60M, and 60C is prohibited.

Next, an example of read processing and determination processing executed by the control unit 100 in the second embodiment will be described with reference to the flowchart of FIG. 12 . Here, only parts different from the first embodiment will be described, and descriptions of common parts will be omitted.

In the second embodiment, in step S5, when the controller 100 determines that the life progress of the first developing unit 60K is equal to or greater than the second threshold value (S5, Yes), the image using the first developing unit 50K is A flag is set to prohibit the formation (S10), and the process ends.

Also in the second embodiment described above, the same effect as in the first embodiment can be obtained.

Although the embodiments of the present disclosure have been described above, the present disclosure is not limited to the above embodiments. The specific configuration can be changed as appropriate without departing from the gist of the present disclosure.

In the above-described embodiment, in order to make the life of the first developing unit 50K longer than the life of the second developing units 50Y, 50M, 50C, the carrier CR in the first developing container 62K is reduced to the second developing containers 62Y, 62M, 62C. Although the amount of filling of the carrier CR is larger than that of the carrier CR inside, another method may be used to make the life of the first developing unit 60K longer than the lives of the second developing units 60Y, 60M, and 60C.

For example, the carrier CR in the first developing container 62K has a thicker coat layer on the surface than the carrier CR in the second developing containers 62Y, 62M, and 62C. It may be longer than the life of the units 60Y, 60M, 60C.

For example, by making the carrier CR in the first developing container 62K harder than the carrier CR in the second developing containers 62Y, 62M, and 62C in the surface coat layer, the life of the first developing unit 60K can be extended to the second developing container 62K. It may be longer than the life of the units 60Y, 60M, 60C.

For example, by making the toner TN in the first developing container 62K more resistant to abrasion of the carrier CR than the toner TN in the second developing containers 62Y, 62M, and 62C, the life of the first developing unit 60K can be shortened by the second developing. It may be longer than the life of the units 60Y, 60M, 60C. In order to make the toner TN less likely to be worn, for example, the toner TN or the additive for the toner TN may be made nearly spherical in particle shape.

In the above-described embodiment, black was exemplified as an example of the specific color, but the specific color may be other than black.

In the above-described embodiments, the toner sensor is a magnetic sensor capable of measuring magnetic permeability, but it may be a physical sensor that measures the amount of toner or stirring torque, and measures transmitted light or reflectance of toner. It may be an optical sensor.

In the above-described embodiment, the drum memory has the first to fifth storage areas, but other storage areas may be provided. Also, the order of the storage areas may be changed.

In the above-described embodiment, the control voltage information is measured when the drum unit 50 is manufactured and stored in advance in the drum memory DM, but the present invention is not limited to this.
For example, when a new drum unit 50 containing a predetermined amount of toner TN in the developer container 62 is attached to the color printer 1, the controller 100 measures the amount of toner with the toner sensor 66 and measures the toner amount with the toner sensor 66. The control voltage information may be determined such that the measurement signal indicates a predetermined amount, and the determined control voltage information may be written in the drum memory DM.
According to this configuration, since the control voltage information is determined at the place where the color printer 1 is actually used, the control voltage information can be acquired according to the environment of the place where the color printer 1 is used, and the accuracy of the toner sensor 66 is improved.

In the embodiment described above, the signal measured by the toner sensor 66 was a voltage value, but the measurement signal measured by the toner sensor 66 may be a current value.

In the above-described embodiment, the voltage value is stored in the drum memory DM as the control voltage information.

In the above-described embodiment, a plurality of control voltage generators are provided corresponding to a plurality of toner sensors, but one control voltage generator may be provided for a plurality of toner sensors. In this case, the control voltage generator sequentially generates control voltages for the plurality of toner sensors according to instructions from the controller.

In the above-described embodiments, the smoothing circuit generates the control voltage, but the configuration is not limited to this. For example, the control voltage may be generated by transforming the input voltage using a resistance voltage division method, a switching regulator method, or the like.

In the above-described embodiment, the present disclosure is applied to the color printer 1, but the present disclosure is not limited to this, and may be applied to other image forming apparatuses such as copiers and multifunction machines.

Each element described in the above-described embodiment and modified examples may be combined arbitrarily and implemented.

1 color printer 10 apparatus body 50 drum unit 50K first developing unit 50Y second developing unit 51 photoreceptor drum 51K first photoreceptor drum 51Y, 51M, 51C second photoreceptor drum 60 developing unit 60K first developing unit 60Y, 60M, 60C second developing unit 61 magnetic roller 61K first magnetic roller 61Y, 61M, 61C second magnetic roller 62 developing container 62K first developing container 62Y, 62M, 62C second developing container 66 toner sensor 66K first toner sensor 66Y, 66M , 66C Second toner sensor 100 Control unit 110 Main body memory CR Carrier DM Drum memory DM1 First storage area DM2 Second storage area DM3 Third storage area DM4 Fourth storage area DM5 Fifth storage area TC Toner cartridge TCK First toner cartridge TCY, TCM, TCC Second toner cartridge TM Toner memory TMK First toner memory TMY, TMM, TMC Second toner memory TN Toner

Claims (20)

a first photoreceptor drum;
A first development unit,
a first magnetic roller that supplies toner of a specific color to the first photosensitive drum;
a first developer container containing a carrier;
a first conveying member positioned in the first developer container, the first conveying member being capable of conveying toner and carrier toward the first magnetic roller;
a first developer unit having
a second photoreceptor drum;
a second development unit,
a second magnetic roller that supplies toner of a color other than a specific color to the second photoreceptor drum;
a second developer container containing a carrier;
a second conveying member positioned in the second developer container, the second conveying member being capable of conveying toner and carrier toward the second magnetic roller;
a second developer unit having
with
The drum unit, wherein the life of the first developing unit is longer than the life of the second developing unit. 2. The drum unit according to claim 1, wherein the carrier in the first developer container has a larger filling amount than the carrier in the second developer container. 3. The drum unit according to claim 1, wherein the carrier in the first developer container has a thicker surface coat layer than the carrier in the second developer container. 4. The drum unit according to claim 1, wherein the carrier in the first developer container has a harder surface coat layer than the carrier in the second developer container. 5. The drum unit according to claim 1, wherein the toner of the specific color wears the carrier less easily than the toner of the color other than the specific color. The drum unit
a drum memory having a first storage area for storing first development life information regarding the life of the first development unit and a second storage area for storing second development life information regarding the life of the second development unit;
a first toner sensor capable of outputting a signal corresponding to the toner concentration in the first developer container;
a second toner sensor capable of outputting a signal corresponding to the toner concentration in the second developer container;
The drum memory is
first control voltage information for generating a control voltage, which is a voltage for controlling the measurement signal of the first toner sensor;
and second control voltage information for generating a control voltage that is a voltage for controlling the measurement signal of the second toner sensor. 2. The drum unit according to item 1. The first development life information is at least one of the number of rotations of the first magnetic roller, the number of prints printed using the first development unit, and the dot count printed using the first development unit. including
The second development life information is at least one of the number of rotations of the second magnetic roller, the number of prints printed using the second development unit, and the dot count printed using the second development unit. 7. The drum unit of claim 6, comprising: 8. The drum unit according to any one of claims 1 to 7, wherein the drum unit is attachable to or detachable from the image forming apparatus. 8. A drum unit according to any one of claims 1 to 7, wherein said specific color is black. An image forming apparatus to which the drum unit according to any one of claims 1 to 9 can be attached, comprising a control section,
The control unit
a reading process for reading first development life information regarding the life of the first development unit and second development life information regarding the life of the second development unit;
a determination process for determining whether the first development unit and the second development unit are usable based on the information read in the read process;
In the determination processing, when it is determined that either one of the first development unit and the second development unit is not usable, the one development unit out of the first development unit and the second development unit is used. and a first process of forming an image using the other developing unit. When the controller determines in the determination process that the second development unit cannot be used, in the first process, the image is developed using the first development unit without using the second development unit. 11. The image forming apparatus according to claim 10, wherein the image forming apparatus When the controller determines in the determination process that the first development unit cannot be used, in the first process, the image is developed using the second development unit without using the first development unit. 12. The image forming apparatus according to claim 10, wherein the image forming apparatus forms an image. The image forming apparatus includes a plurality of the second developing units,
the plurality of second developing units corresponding to different colors,
In the first process, the controller mixes toners of a plurality of the second developing units when forming an image of a specific color by using the second developing unit instead of the first developing unit. 13. The image forming apparatus according to claim 12, characterized by: 14. The image forming apparatus according to claim 13, wherein the controller mixes the toners of the plurality of second developing units to form an image of a specific color. The drum unit
a first storage area for storing first development life information relating to the life of the first development unit;
15. The image according to any one of claims 10 to 14, further comprising a drum memory having a second storage area for storing second development life information relating to the life of the second development unit. forming device. The control unit
calculating a life progression degree indicating a progress degree of the life of the first developing unit from the first development life information stored in the first storage area;
notifying that the drum unit should be replaced without prohibiting image formation using the first developing unit when the calculated degree of progress of life is equal to or greater than a first threshold;
16. The method according to claim 15, wherein image formation using the first developing unit is prohibited when the calculated degree of progress of life is greater than or equal to a second threshold in which the degree of progress of life is greater than the first threshold. image forming device. The control unit
calculating the progress of the life of the first developing unit from the first development life information stored in the first storage area;
notifying that the drum unit should be replaced without prohibiting image formation using the first developing unit when the calculated degree of progress of life is equal to or greater than a first threshold;
executing extension reception processing for receiving input of an instruction to extend the use of the first developing unit when the calculated degree of progress of life is greater than or equal to a second threshold, which is larger than the first threshold;
prohibiting image formation using the first developing unit when an instruction to extend the use of the first developing unit is not input in the extension accepting process;
In the extension accepting process, when an instruction to extend the use of the first developing unit is input, the extended use is permitted until the degree of progress of the life of the first developing unit reaches a third threshold larger than the second threshold. 17. The image forming apparatus according to claim 16, characterized by: The control unit
calculating the degree of progress of the life of the second developing unit from the second development life information;
not prohibiting image formation using the second developing unit and notifying that the drum unit should be replaced when the calculated degree of progress of life is equal to or greater than a fourth threshold;
18. Image formation using the second developing unit is prohibited when the calculated degree of progress of life is equal to or greater than a fifth threshold that is greater than the fourth threshold. 10. The image forming apparatus according to claim 1. The control unit
calculating the degree of progress of the life of the second developing unit from the second development life information;
not prohibiting image formation using the second developing unit and notifying that the drum unit should be replaced when the calculated degree of progress of life is equal to or greater than a fourth threshold;
if the calculated degree of progress of life is greater than or equal to a fifth threshold that is greater than the fourth threshold, executing extension acceptance processing for accepting input of an instruction to extend the use of the second developing unit;
prohibiting image formation using the second developing unit when an instruction to extend the use of the second developing unit is not input in the extension accepting process;
In the extension accepting process, when an instruction to extend the use of the second developing unit is input, the extended use is permitted until the degree of progress of the life of the second developing unit reaches a sixth threshold larger than the fifth threshold. 18. The image forming apparatus according to any one of claims 15 to 17, characterized by: The drum unit
a first toner sensor capable of measuring the amount of toner in the first developer container;
a second toner sensor capable of measuring the amount of toner in the second developer container;
The control unit
20. Image formation using the first developing unit is prohibited when the amount of toner in the first developing container measured by the first toner sensor is larger than a predetermined value. The image forming apparatus according to any one of items 1 to 3.

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