JP2001109357A - Image forming device, process cartridge and developing cartridge - Google Patents

Abstract

PROBLEM TO BE SOLVED: To read information on optimum image formation and life at any necessary time. SOLUTION: RAM23 and RAM24 are loaded on a developing cartridge 1 stored in a rotary drum 11 and a process cartridge respectively. Information on an image forming condition and life are summarized in RAM24 on a process cartridge 4-side so as to process it.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to an image forming apparatus, a process cartridge and a developing cartridge.

[0002] In the present invention, as an image forming apparatus,
For example, an electrophotographic copying machine, an electrophotographic printer (eg, LE
D printer, laser beam printer, etc.), electrophotographic facsimile, and electrophotographic word processor.

[0003]

2. Description of the Related Art FIG. 4 shows an example of a conventional multicolor image forming apparatus.

The multicolor image forming apparatus shown in FIG. 1 is an electrophotographic recording apparatus used as a copying machine or a page printer engine.

This multicolor image forming apparatus includes developing process units (hereinafter referred to as "developing units") 101y, 101m, 101c, and 101k, which are four-color developing units, and a photosensitive drum 105 that is an electrophotographic photosensitive member. And a latent image processing unit (hereinafter simply referred to as “process unit”) 104. Further, the image forming apparatus includes a rotary drum 111 as a rotating body, a laser exposure device 112, an intermediate transfer belt 113 as an intermediate transfer body,
A secondary transfer roller 114 and a fixing device 116 are provided. The image forming apparatus according to the present embodiment employs a method of forming a full-color image by superimposing four color toner images on the intermediate transfer belt 113.

The process unit 104 includes the photosensitive drum 1
05, a charging roller 106, and a cleaning blade 107 and a waste toner box 108 constituting a cleaning means are integrated.

Hereinafter, an image forming process of the multi-color image forming apparatus having the above configuration will be described.

A charging bias is applied between the charging roller 106 and the photosensitive drum 105 by a charging bias power supply (not shown), and the surface of the photosensitive drum 105 is charged substantially uniformly. The charged surface of the photosensitive drum 105 is scanned and exposed by infrared laser light output from the laser exposure device 112. This laser light corresponds to a pixel signal based on image information decomposed into four colors of yellow y, magenta m, cyan c, and black k, and an electrostatic latent image is formed on the surface of the photosensitive drum 105 in this order. You.

The formed electrostatic latent image is developed at the developing position by the developing units 101y, 101m, 101c and 101k. Prior to the development, the developing unit 101y of the color (first yellow) corresponding to the color separation image is transported to the developing position by rotating the rotary drum 111. When the electrostatic latent image on the photosensitive drum 105 passes through the developing position, a developing bias is applied to the developing unit 101y from a developing bias power supply (not shown) to develop the electrostatic latent image.

A yellow toner image obtained by developing the yellow color separation image is transferred onto the intermediate transfer belt 113 (primary transfer). The intermediate transfer belt 113 is a photosensitive drum 1
05 is pressed against the photosensitive drum 105 with a predetermined pressing force, and is rotationally driven at the same peripheral speed in the same direction at the portion facing the photosensitive drum 105. A primary transfer bias is applied between the photosensitive drum 105 and the intermediate transfer belt 113 via a primary transfer roller 115 from a primary transfer bias power supply (not shown), and the yellow toner image is transferred onto the intermediate transfer belt 113 by the primary transfer bias. You.

Similarly, a magenta toner image is formed on the photosensitive drum 105 through the charging, exposing, and developing steps, and the magenta toner image has no color shift on the yellow toner image already formed on the intermediate transfer belt 113. Are transferred in a superimposed manner. Similarly, the cyan toner image and the black toner image are sequentially superimposed and transferred on the intermediate transfer belt 113, whereby a full-color image in which four color toner images are superimposed on the intermediate transfer belt 113 is formed. The transfer residual toner remaining on the photosensitive drum 105 due to the transfer is removed from the photosensitive drum 105 by the cleaning blade 107.

The full-color image on the intermediate transfer belt 113 is taken out one by one from a paper feed cassette 118 by a secondary transfer roller 114 by a pickup roller 119, and is conveyed to a registration roller 121 by a conveyance roller 120. The secondary transfer is performed on the transfer material 102 that has been taken and fed to the secondary transfer roller 114.
The secondary transfer roller 114 is separated from the intermediate transfer belt 113 until a full-color image is formed, and is brought into contact immediately before the full-color image is formed and reaches the secondary transfer position. Transfer material 102 conveyed simultaneously with this contact
, A secondary transfer bias is applied to the intermediate transfer belt 113 by a secondary transfer bias power supply (not shown), and a full-color image is transferred onto the transfer material P. The transfer material P to which the full-color image has been transferred is conveyed to the fixing device 116, where it is fixed by heat and pressure to become a recorded image.

The above is a series of full-color image forming steps.
When a plurality of images are created, the above series of steps is repeated. Of course, when an image of only black and white is created, only the black developing unit 101k is used from the beginning, and the step of overlapping other colors is omitted.

In such an image forming apparatus, in order to facilitate maintenance of the apparatus, some process elements may be combined or a single process element may be used as a process unit. In the example,
As described above, the photosensitive drum 105 and the charging roller 106
The cleaning unit 107 is integrated with the process unit 104, and the developing device is changed to the developing units 101y and 101y.
m, 101c, and 101k.

In the image forming apparatus provided with the process unit and the developing unit, a nominal life which is a standard for guaranteeing the quality of each process unit and the developing unit is determined. It is often urged to replace the developing unit. In many cases, the nominal life of the process unit and the developing unit is indicated by a simple value such as the maximum number of sheets that can be passed.
A method was used to warn the user of the replacement time.

However, with the development of functions of the image forming apparatus, the printing mode, that is, the image forming mode has become complicated (for example, image forming of both A3 paper and A4 paper, or replacement of a plurality of developing units). The maximum number of sheets passing through the developing unit and the process unit is greatly changed depending on the use condition.

For this reason, the life of each unit is not defined by the conventional nominal life, but a storage element is provided as storage means for storing life detection parameters such as the total number of printed sheets, drive time, and energization time. There has been proposed a method for detecting the life.

The constituent elements of each of the above units have slight variations in physical characteristics and characteristic changes due to use.
For this reason, a storage element for storing the physical characteristics of each component is provided in the process unit and the developing unit itself,
There has been proposed a method of correcting image forming conditions in an image forming apparatus main body. Also in this case, the history of the driving time, the energizing time, the integrated current value, and the like may be stored in the storage element, and the fine image forming conditions may be corrected.

The process unit and the developing unit can be configured as a process cartridge and a developing cartridge which are detachable from the apparatus main body so that the user can easily replace the process unit and the developing unit. According to the process cartridge and the developing cartridge system, the maintenance of the apparatus can be performed by the user himself without depending on the service person, so that the operability can be remarkably improved.

[0020]

In a color laser beam printer, a process unit and a developing unit are often separated from each other. In particular, in a case where a rotary system is employed as in this embodiment, when forming an image, Since a plurality of developing units rotate, when reading information from the storage element of each developing unit, there are few reading opportunities and the control is complicated.

For example, if information is forcibly read / written from / to the memory element of the developing unit during image formation, the stored content of the memory element may be deteriorated due to poor contact of the terminal connecting the developing unit and the apparatus main body. Is crazy,
In the worst case, the developing unit itself may become unusable.

Also, if the user wants to know the life of the process unit and the developing unit at any time,
During image formation, it is necessary to wait for or stop the operation, which is inconvenient.

Accordingly, an object of the present invention is to provide a simple configuration,
An object of the present invention is to provide an image forming apparatus capable of reading information on optimal image formation and life at any time when necessary, and a process cartridge and a developing cartridge which are detachable from the image forming apparatus.

[0024]

The above object is achieved by an image forming apparatus, a process cartridge and a developing cartridge according to the present invention. In summary, the present invention relates to an image forming apparatus having a process cartridge and a developing cartridge detachably mounted thereon, each of which includes a non-volatile storage unit for storing a use state, and stores information on the developing cartridge in a non-volatile manner. An image forming apparatus characterized in that the information is collectively stored in a storage unit.

The information stored in the non-volatile storage means of the process cartridge is used to determine optimum image forming conditions,
It is preferable to refer to this and life detection. Preferably, the plurality of developing cartridges are housed in a rotating body.

According to another aspect of the present invention, in an image forming apparatus having a process unit and a developing unit each equipped with a non-volatile storage unit for storing a use state, information of the developing unit is stored in the non-volatile memory of the process unit. An image forming apparatus is provided, wherein the image forming apparatus is collectively stored in sex storage means.

According to another aspect of the present invention, there is provided a process cartridge which is detachably mounted on a main body of an image forming apparatus and has a non-volatile storage means for storing a use state. A process cartridge is provided, wherein information on a developing cartridge which is freely mounted and has a non-volatile storage means for storing a use state is collectively stored in the non-volatile storage means of the process cartridge.

Further, according to another aspect of the present invention,
In a developing cartridge which is detachably attached to the image forming apparatus main body and has a nonvolatile storage means for storing a use state, information of the developing cartridge is stored in a process cartridge detachably attached to the image forming apparatus main body. The developing cartridge is characterized in that it is collectively stored in a non-volatile storage means for storing a use state.

[0029]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an image forming apparatus, a process cartridge and a developing cartridge according to the present invention will be described in more detail with reference to the drawings.

FIG. 1 shows an embodiment of an image forming apparatus to which a process cartridge and a developing cartridge according to the present invention can be removably mounted. The image forming apparatus according to the present embodiment is a color laser beam printer (hereinafter, simply referred to as “printer”).

The printer of this embodiment includes four color developing cartridges 1y, 1m, 1c and 1k, and a process cartridge 4 including a photosensitive drum 5 as an electrophotographic photosensitive member. Further, the printer includes a rotary drum 11,
The apparatus includes a laser exposure device 12, an intermediate transfer belt 13, which is an intermediate transfer member, a secondary transfer roller 14, a fixing device 16, and the like. The printer employs a method of forming a full-color image by superimposing four color toner images on the intermediate transfer belt 13.

The process cartridge 4 integrates a photosensitive drum 5, a charging roller 6, a cleaning blade 7 constituting a cleaning means, and a waste toner box 8, and is formed into an external appearance as shown in FIG. On the other hand, it is detachable via the mounting guide means 22.

In this embodiment, four developing cartridges 1
y, 1m, 1c, 1k, rotary drum 1
1 is provided with a toner remaining amount detecting mechanism 3y, 3m, 3c, 3k and an integrated driving time detecting mechanism (not shown). The developing cartridges 1y, 1m, 1c, and 1k have RAMs 23y, 23m, 23m as nonvolatile storage means, respectively.
c and 23k, and stores information such as the toner remaining amount, the integrated driving time, and the physical characteristics of the toner that are different for each color. As shown in FIG. It is connected to an internal arithmetic unit 27 so that data can be read / written.

In the following description, each developing cartridge 1y, 1m, 1c, 1k and each RAM 23
In the case of contents common to y, 23m, 23c, and 23k, their reference numbers are simply described as 1,23.

The shapes of the four developing cartridges 1 are the same irrespective of the color of the toner, and can be easily attached to and detached from the printer main body 10 by sliding in the longitudinal direction with respect to the rotary drum 11 on which the developing cartridges are mounted. It has a configuration. Each developing cartridge 1 includes a rotary drum 1
By one rotation, the photosensitive drum 5 is sequentially transported to a developing position facing the photosensitive drum 5.

The photosensitive drum 5 is formed by applying a plurality of photosensitive layers to a cylindrical aluminum cylinder. The charging roller 6 has a volume resistivity of 10 ⁸ to ¹⁰ 10 around the cored bar.
It has a conductive elastic layer of about Ωcm, and comes into contact with the photosensitive drum 5 and rotates with the rotation of the photosensitive drum 5.

The cleaning blade 7 is made of a urethane rubber elastic body, and is constantly pressed against the photosensitive drum 5 with a predetermined pressure to mechanically scrape off the transfer residual toner remaining on the photosensitive drum 5. The scraped waste toner is transferred to the transport mechanism 1 inside the cleaning blade 4.
7, the paper is sent to the waste toner box 8 by the transport mechanism 17 inside the process cartridge 4.

The waste toner box 8 occupies most of the volume of the process cartridge 4. A waste toner amount detection mechanism 9 is provided in the waste toner box 8, and controls the printer main body 10 so as not to start a new image forming operation when the waste toner box 8 is almost full. A RAM 24 is mounted on the waste toner box 8 as a non-volatile storage unit. When the RAM 24 is mounted on the printer main body 10, as shown in FIG. ) 27 so that data can be read / written.

The arithmetic unit 27 is connected to a control unit (control circuit) 28 of the printer body 10, and exchanges data with the RAMs 23 and 24 of each developing cartridge 1 and the process cartridge 4 based on a command from the control unit 28. Perform

Next, an image forming process of the multi-color image forming apparatus having the above configuration will be described.

A charging bias is applied between the charging roller 6 and the photosensitive drum 5 by a charging bias power supply (not shown), whereby the surface of the photosensitive drum 5 is charged substantially uniformly. The charged surface of the photosensitive drum 5 is scanned and exposed by infrared laser light output from the laser exposure device 12. This laser beam corresponds to a pixel signal based on image information decomposed into four colors of yellow y, magenta m, cyan c, and black k, and an electrostatic latent image is formed on the surface of the photosensitive drum 5 in this order. You.

The formed electrostatic latent image is developed by the developing cartridge 1 at the developing position. Prior to this development, a developing process unit 1y of a color (first yellow) corresponding to the color separation image is transported to the developing position by rotating the rotary drum 11. When the electrostatic latent image on the photosensitive drum 5 passes through the developing position, a latent image is developed by applying a developing bias to the developing cartridge 1y from a developing bias power supply (not shown).

The yellow toner image obtained by developing the yellow color separation is transferred onto the intermediate transfer belt 13 (primary transfer). The intermediate transfer belt 13 is pressed against the photosensitive drum 5 with a predetermined pressing force, and is rotationally driven in the same direction and at the same peripheral speed at a portion facing the photosensitive drum 5. A primary transfer bias is applied between the photosensitive drum 5 and the intermediate transfer belt 13 via a primary transfer roller 15 from a primary transfer bias power source (not shown), and the yellow toner image is transferred onto the intermediate transfer belt 13 by the primary transfer bias. You.

Similarly, a magenta toner image is formed on the photosensitive drum 5 through the charging, exposing and developing steps, and the magenta toner image has no color shift on the yellow toner image already formed on the intermediate transfer belt 13. Are transferred in a superimposed manner. Similarly, a cyan toner image and a black toner image are sequentially superimposed and transferred on the intermediate transfer belt 13, thereby forming a full-color image in which four toner images are superimposed on the intermediate transfer belt 13. The transfer residual toner remaining on the photosensitive drum 5 due to the transfer is removed from the photosensitive drum 5 by the cleaning blade 7.

The full-color image on the intermediate transfer belt 13 is fed by a secondary transfer roller 14 to a sheet feeding cassette 18.
The sheet is taken out one by one by a pickup roller 19, conveyed to a registration roller 21 by a conveyance roller 20, and secondarily transferred onto the transfer material 2 fed to the secondary transfer roller 14 with a timing. Secondary transfer roller 14
Is the intermediate transfer belt 1 until a full-color image is formed.
3 and is brought into contact immediately before the full-color image is formed and reaches the secondary transfer position. A secondary transfer bias is applied by a secondary transfer bias power supply (not shown) between the intermediate transfer belt 13 and the transfer material 19 conveyed at the same time as the contact, and a full-color image is transferred onto the transfer material P. You. Transfer material P on which full-color image has been transferred
Is transported to a fixing device 16 where it is fixed by heat and pressure to form a recorded image.

The above is a series of full-color image forming steps.
When a plurality of images are created, the above series of steps is repeated. Of course, when an image of only black and white is created, only the black developing unit 1k is used from the beginning, and the step of overlapping other colors is omitted.

In the printer capable of forming both a multi-color image and a single-color image as in this embodiment, the degree of wear of the photosensitive layer of the photosensitive drum 5 depends on whether a single full-color or single-color image is formed. It depends on the case. In addition, when the driving time of the photosensitive drum 5 is changed and the image is formed continuously or intermittently, the dirt on the photosensitive drum 5 and the intermediate transfer belt 3 is removed before and after the image formation. Since there is a cleaning sequence to remove,
As a result, the degree of wear per image formation for one sheet differs. In addition, since the components of each developing cartridge and the process cartridge have a slight variation in physical characteristics and a change in characteristics due to use, fine adjustment to image forming conditions is performed in consideration of the usage of each process cartridge. There must be.

Hereinafter, an operation related to reading / writing of the RAMs 23 and 24 for storing information of the developing cartridge 1 and the process cartridge 4 will be described.

The information of each developing cartridge 1 and the process cartridge 4 is read by utilizing the heating operation or the returning operation time of the fixing device 16 when the power is turned on.

First, the control unit 28 puts the arithmetic unit 27 in the receiving state, and stores the identification data of the developing cartridge 1 and the process cartridge 4 stored in the RAMs 24 and 23, the integrated driving time data, the integrated energizing time, the integrated charging time, and the like. , Are read through connectors 25 and 26, respectively. At this time, information is read from the four RAMs 23 mounted on each developing cartridge 1 by the rotary drum 11 so that the connector 26 is reliably connected.
The developing cartridges 1 are sequentially conveyed and the rotary drum 11
Is performed after confirming that the rotation of has stopped. Next, the information obtained from each RAM 23 is stored in the RAM 24.

When data relating to each of the developing cartridge 1 and the process cartridge 4 is required to correct the image forming conditions during image formation or to judge the life, the control device 28 controls the arithmetic device 27. To R
The data stored in the AM 24 is read and used.

The control device 28 transmits the data regarding the developing cartridge 1 and the process cartridge 4 calculated by the arithmetic unit 27 in the process of forming an image through the connector 25 every time a predetermined image forming operation is completed.
It is controlled to write to AM24.

When the print signal is not input for a certain period of time after the completion of the image formation, the control device 28 confirms that the rotation of the rotary drum 11 has stopped, and at that time,
Data such as the integrated driving time and the integrated energizing time of the developing cartridge 1 located opposite the photosensitive drum 5 are sequentially written to the RAM 23 of the developing cartridge 1 from the arithmetic unit 27 through the connector 26. Similarly, RAM2
4, the data of both the process cartridge 4 and the developing cartridge 1 is written via the connector 25.

Next, the life detection will be described.

Based on the information on the waste toner amount detection mechanism 9 of the process cartridge 4, the integrated driving time, and the integrated energizing time read into the arithmetic unit 27, the waste toner amount is full in the waste toner box 8 or integrated. When it is determined that the energization time and the integrated drive time have exceeded the predetermined values, the control device 2
8 causes the display device 20 to display on the display device 20 that the process cartridge 4 is “unusable”.
The control is performed so that the “unusable information” of No. 4 is set to “ON”.
If the "unusable information" is "ON" when the process cartridge 4 is taken out of the apparatus, "unusable" is immediately displayed.

Similarly, from the information on the remaining toner amount detecting mechanism 3 of the developing cartridge 1 and the integrated charging time and the integrated energizing time,
If it is determined that the remaining amount of toner is small or the accumulated driving time exceeds the specified value, a “replacement warning” is displayed for the developing cartridge 1 of that color, and the “unusable information” of the RAM 23 is displayed. Set to “ON”.

As described above, when some of the developing cartridge 1 and the process cartridge 4 cannot be used,
The printer main body 10 is controlled so as not to enter a new image forming operation.
Is controlled.

If it is detected that the developing cartridge 1 or the process cartridge 4 has been replaced while the power is on, the replaced cartridge is determined from the cartridge identification data stored in the RAMs 24 and 23 in the same manner as when the power is turned on. The information is rewritten only for the cartridge.

As described above, the data in the RAM 23 of the developing cartridge 1 is read into the RAM 24 of the process cartridge 4 using the standby time of the main body of the image forming apparatus, so that it is necessary to correct the image forming conditions. At some point, even during image formation, stop image formation or read the conditions required for correction without stopping, and perform life detection and correction of image formation conditions while improving the accuracy. Can be.

The gist of the present invention is that the information of the storage element for detecting the life of the components of the developing cartridge or the storage element storing the image forming conditions of the developing cartridge is stored in the process cartridge when the rotary drum is stopped. Since the information can be read even during image formation, the correction to the image forming conditions can be promptly performed. Further, the user can arbitrarily check the remaining amount of toner and know the life, so that the operability by the user himself can be improved.

In the present embodiment, the correction of the image forming conditions of the process cartridge and the developing cartridge and the detection of the service life have been described. However, the present invention is not limited to this. To the purpose. Of course, the storage element is not limited to the RAM, but may be any storage element whose data can be appropriately rewritten.

In the present embodiment, the case where the present invention is applied to a process cartridge and a developing cartridge which can be attached to and detached from the image forming apparatus main body has been described.
The same applies to the process unit and the developing unit incorporated in the conventional image forming apparatus main body described with reference to FIG.

[0063]

As is apparent from the above description, according to the present invention, there is provided an image forming apparatus in which a process cartridge and a developing cartridge, each of which is provided with a nonvolatile storage means for storing a use state, are detachably mounted. By collectively storing the information of the developing cartridge in the non-volatile storage means of the process cartridge, the information on the optimal image formation and the life can be read whenever necessary, which contributes to the improvement of operability. be able to.

Further, in an image forming apparatus in which a non-volatile storage means for storing a use state is mounted, and an image forming apparatus in which a developing unit is detachably mounted, information on the developing unit is stored in a non-volatile storage means of the process unit. By storing them together, the same effect as described above can be obtained.

Further, in a process cartridge which is detachably mounted on the main body of the image forming apparatus and has a non-volatile storage means for storing a use state, the process cartridge is detachably mounted on the main body of the image forming apparatus and stores the use state. The same effect as described above can be obtained by collectively storing the information of the developing cartridge having the nonvolatile storage means in the nonvolatile storage means of the process cartridge.

According to another aspect of the present invention, in a developing cartridge which is detachably mounted on the image forming apparatus main body and has a nonvolatile storage means for storing a use state, information on the developing cartridge is stored in the developing cartridge. The same effect as described above can be obtained by storing the process cartridges detachably mounted in the image forming apparatus main body in a non-volatile storage unit for storing the use status.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram showing an embodiment of an image forming apparatus having a process cartridge and a developing cartridge according to the present invention.

FIG. 2 is an external view of the process cartridge of FIG.

FIG. 3 is an explanatory diagram showing a connection state between the apparatus main body, a process cartridge and a developing cartridge.

FIG. 4 is a configuration diagram illustrating an example of a conventional multicolor image forming apparatus.

[Explanation of symbols]

1 (1y, 1m, 1c, 1k) Developing cartridge 4 Process cartridge 10 Printer main body (image forming apparatus main body) 11 Rotary drum (rotary body) 23 (23y, 23m, 23c, 23k) RAM (non-volatile storage means) 24 RAM (non-volatile storage means)

Continued on the front page F-term (reference) 2H027 DA39 DD02 DD03 DE10 EC10 ED02 ED03 ED08 ED24 ED27 ED28 EE02 EE08 EE10 EF01 EF15 EJ05 EK03 FA28 GA30 GA47 GA54 GB05 GB10 HB02 HB05 HB13 HB15 HB18 DA13 DA13 DAB DA DA DA EA18 2H077 BA09 DA15 DA35 DB10 DB14 DB25 GA04 GA13

Claims (6)

[Claims] 1. An image forming apparatus in which a process cartridge and a developing cartridge each having a non-volatile storage unit for storing a use state are detachably mounted, wherein information on the developing cartridge is stored in a non-volatile storage unit of the process cartridge. An image forming apparatus, wherein the image forming apparatus collectively stores the information. 2. The image forming apparatus according to claim 1, wherein information stored in a non-volatile storage unit of the process cartridge is referred to for determining an optimum image forming condition and detecting a life. 3. The image forming apparatus according to claim 1, wherein a plurality of the developing cartridges are housed in a rotating body. 4. An image forming apparatus having a process unit and a developing unit each including a non-volatile storage unit for storing a use state, wherein information on the developing unit is collectively stored in the non-volatile storage unit of the process unit. An image forming apparatus. 5. A process cartridge which is detachably mounted on an image forming apparatus main body and has a non-volatile storage means for storing a use state, wherein said process cartridge is detachably mounted on said image forming apparatus main body and stores a use state. A process cartridge, wherein information of a developing cartridge having a nonvolatile storage unit is collectively stored in the nonvolatile storage unit of the process cartridge. 6. A developing cartridge which is detachably mounted on a main body of an image forming apparatus and has a non-volatile storage means for storing a use state, wherein information on the developing cartridge is removably mounted on the main body of the image forming apparatus. A developing cartridge, wherein the developing cartridge is collectively stored in a non-volatile storage unit for storing a use state of the process cartridge.