JP2001034125A - Using amount storing and judging method of process unit, image forming device and process unit - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a using amount storing and judging method of a process unit by which the using amount of the process unit can be stored in the process unit itself and judged in an image forming device main body. SOLUTION: In this using amount storing and judging method, the using amount of the process unit 16 is stored in the unit 16 itself as the position of a dielectric body 35 by moving the dielectric body 35 as much as prescribed amount by a main body moving means 37 according to the using amount of the unit 16 detected by a unit using amount detection means when the unit 16 is attached to the image forming device main body and used. Besides, when the unit 16 is attached to the image forming device main body, electrostatic capacity between two electrodes 31 and 32 individually coming into contact with two main-body electric contact points 31b and 32b is measured as a value for discriminating the using amount of the using 16 by a main body measurement means 39.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of determining the storage amount of a process unit used in an electrophotographic image forming apparatus, an image forming apparatus using the same, and a process cartridge.

[0002]

2. Description of the Related Art Conventionally, in an electrophotographic image forming apparatus, information on the amount of use of a process unit detachable from a main body of the image forming apparatus is presented to a user to urge replacement of the process unit at an appropriate time. The following has been done:

Conventional Example 1: Method of Directly Detecting Consumption of Consumable Member The amount of developer in a developing cartridge, the thickness of a photosensitive drum of a photosensitive drum cartridge (process cartridge), etc.
This is an example in which a change in the amount of consumption (use) is directly measured, and the change prompts replacement of a process unit such as the developing cartridge or the photosensitive drum cartridge at an appropriate time.

In this method, since the amount of actual consumption (used) is directly measured, it is possible to warn of replacement of the process unit at a necessary time. 3) It is not possible to use a device which does not directly change in quantity, such as a charging member, a transfer member, a fixing member, or the like and whose life is determined by deterioration, such as the necessity of providing an amount detecting means.

[0005] The developer use amount detecting means includes an antenna detection system for detecting the remaining amount of the developer by a change in the capacitance between the developer carrier and the capacitance detection member (antenna).
A piezo element is arranged below the side surface of the developer hopper, a piezo detection method for detecting a decrease in the amount of the developer in the hopper, and an optical path for transmitting an LED or laser light to the developer hopper or the developing chamber is provided. There is an optical detection method for detecting the presence or absence of a developer based on the presence or absence. As a means for detecting the amount of consumed film thickness of the photosensitive drum, there is a surface potential detecting method in which a constant voltage is applied to a charging member to measure a change in charged surface potential and convert the measured value into a photosensitive drum film thickness. These are methods to detect several points just before the life of the process unit, mainly through the life of the process unit.
It is not suitable for applications such as displaying the usage amount as a percentage. Further, as a means for detecting the thickness consumption of the photosensitive drum, there is a current value detection method in which a constant voltage is applied to the charging member to measure a flowing current, convert the current into a photosensitive drum film thickness, and sequentially display the used amount as a percentage. There is a tendency that the measurement current value varies in a temperature and humidity environment and the detection accuracy is lowered.

Conventional Example 2: Counting the number of times of image formation, etc., and integrating it into the memory of the image forming apparatus main body or the process unit.
Storing Method Counts parameters relating to the consumption of the process unit such as the photosensitive drum rotation time, the number of formed images, the number of image forming dots, and the bias application time, and further stores the counted information in a memory (EEPR) of the image forming apparatus main body or the process unit.
This is an example in which usage information is presented to the user based on the integrated information, and the replacement of the process unit is prompted at an appropriate time.

This type of process unit, such as a charging cartridge, a transfer cartridge, or a fixing cartridge, which is unlikely to be removed from the main body of the image forming apparatus until the end of its life, accumulates and stores usage information in a memory of the main body of the image forming apparatus. , It works satisfactorily by resetting the memory when replacing the process unit.However, like the photosensitive drum cartridge, developing cartridge, cleaning cartridge, etc., the process unit can be removed from the main body of the image forming apparatus even in the middle of its life and can be mounted again. In some cases, when the unit is replaced, the accumulated usage value up to that point is reset, and the next time the unit is remounted, the life warning cannot be accurately given. In such a case, the process unit itself is provided with a memory, and the accumulated usage information of the process unit is stored.
Even if re-attachment is performed, usage amount display, life warning, etc. can be accurately performed.

[0008]

In recent years, with the spread of electrophotographic image forming apparatuses such as laser printers and copiers,
When several identical printers are lined up in offices, etc., exchange of process units between identical printers,
The use of a high-definition image unit and a highly durable specification unit is being replaced. In addition, interest in improving usability has been increasing, and it has been demanded that the user can sequentially announce how much of the process unit is used and how much printing can be performed at any stage regarding the display of the use amount of each process unit.

In response to these needs, as in Conventional Example 2,
By providing a memory in the process unit itself and accumulating and storing the process unit usage, a function of sequentially announcing the process unit usage is realized.

The present invention is a further development of the above-mentioned prior art, and the main purpose of the present invention is to store the usage of a process unit in the process unit itself, with or without replacement of the process unit. It is an object of the present invention to provide a method of storing the amount of use of a process unit in which the amount of use of the process unit can be determined in the image forming apparatus main body.

Another main purpose is to be able to store the amount of use of the process unit in the process unit itself and to determine the amount of use of the process unit in the image forming apparatus main body irrespective of whether the process unit is replaced or not. To provide an image forming apparatus capable of performing the following.

Another main purpose is to store the used amount of the process unit in the process unit itself, regardless of whether or not the image forming apparatus main body is replaced and used. It is an object of the present invention to provide a process unit that can be identified.

Another object of the present invention is to provide a process unit capable of storing the amount of use of the process unit in the process unit itself, regardless of whether the process unit is used for replacement.

[0014]

According to the present invention, there is provided a method for determining a storage amount of a process unit according to the present invention. The method is configured to be detachable from a main body of an image forming apparatus and can be sequentially replaced according to the usage amount. In a method for determining the storage amount of a process unit used in an image forming apparatus for forming an image on a recording medium having a process unit, the process unit includes two main body electrical contacts of the main body of the image forming apparatus When the process unit is mounted on the image forming apparatus main body and used when the process unit is mounted on the main body of the image forming apparatus. The dielectric is applied to the image forming apparatus main body in accordance with the usage of the process unit detected by the unit usage detecting means of the image forming apparatus main body. The amount of use of the process unit is stored in the process unit itself as the position of the dielectric by moving the process unit by a predetermined amount by the main body moving means of the image forming apparatus. The capacitance between the two electrodes that are individually in contact with the two main body electrical contacts is measured as a value for determining the amount of use of the process unit by a main body measuring unit included in the image forming apparatus main body. This is a method for determining the usage storage of the process unit.

According to another aspect of the present invention, there is provided a method of storing the amount of use of a process unit according to the present invention. The method includes a process unit that is detachably attached to an image forming apparatus main body and that can be sequentially replaced according to the amount of use. Then, in the method for determining the amount of use of a process cartridge used in an image forming apparatus for forming an image on a recording medium, the process unit includes a guide member and a moving piece that moves along the guide member. The image forming apparatus main body has a unit usage detecting unit for detecting the usage of the process unit, a main body moving unit for moving the moving frame of the process unit, and two electrodes, A dielectric material movable between the two electrodes and having a predetermined dielectric constant, and a position between the moving piece of the process unit and The image forming apparatus includes: a dielectric moving unit for moving the dielectric; and a main body measuring unit for measuring a capacitance between the two electrodes. Then, the moving frame is moved by a predetermined amount by the main body moving unit in accordance with the used amount of the process unit detected by the unit used amount detecting unit, thereby reducing the used amount of the process unit to the position of the moving frame. When the process unit is mounted on the main body of the image forming apparatus, the dielectric is moved to the position of the moving frame by the dielectric moving means, and the process is performed by the main body measuring means. Measuring the capacitance between the two electrodes as a value for determining the amount of use of the process unit. Scan a density storing discrimination method of the unit.

An image forming apparatus according to the present invention for achieving the above object is configured so as to be detachable from a main body of the image forming apparatus, has a process unit which can be sequentially replaced according to the usage amount, and stores an image on a recording medium. In the image forming apparatus for forming an image forming apparatus, two main body electrical contacts, two electrodes individually contacting the two power supply contacts, and a dielectric having a predetermined permittivity movable between the two electrodes. Mounting means for detachably mounting a process unit having a body, and unit usage detecting means for detecting the usage of the process unit when the process unit is mounted on the image forming apparatus body and used Main body moving means for moving the dielectric of the process unit; and the process unit individually contacting the two main body electrical contacts. Main body measuring means for measuring the capacitance between the two electrodes of the main body, and the main body moving means comprises a main body measuring means for measuring the capacitance of the process unit detected by the unit usage detecting means. By moving the dielectric by a predetermined amount, the amount of use of the process unit is stored in the process unit itself as the position of the dielectric, and the main body measuring means is used when the process unit is mounted on the image forming apparatus main body. Measuring the capacitance between the two electrodes of the process unit that individually contact the two main body electrical contacts as a value for determining the amount of use of the process unit. is there.

According to another aspect of the present invention, there is provided an image forming apparatus configured to be detachable from a main body of the image forming apparatus, and having a process unit that can be sequentially replaced according to a used amount of the image forming apparatus. Mounting means for detachably mounting a process unit having a guide member, and a moving piece moving along the guide member, and an image forming apparatus for forming an image on the image forming apparatus. A unit usage amount detection unit for detecting the usage amount of the process unit when used by being mounted on the apparatus main body, a main body moving unit for moving the moving frame of the process unit, and two electrodes, A dielectric that is movable between the two electrodes and has a predetermined dielectric constant, and a position of the moving piece of the process unit. Dielectric moving means for moving the dielectric, and a main body measuring means for measuring the capacitance between the two electrodes, wherein the main body moving means, the unit usage detecting means By moving the moving frame by a predetermined amount in accordance with the used amount of the process unit to be detected, the used amount of the process unit is stored in the process unit itself as the position of the moving frame, and the dielectric moving unit includes: When the process unit is mounted on the image forming apparatus main body, the dielectric is moved to the position of the moving frame, and the main body measuring unit is configured to move the two dielectric members in a state where the dielectric is moved to the position of the moving frame. An image forming apparatus, wherein an electrostatic capacity between electrodes is measured as a value for determining a usage amount of the process unit.

A process unit according to the present invention for achieving the above object is detachably attached to the image forming apparatus main body, and is a process unit that can be sequentially replaced according to the amount of use. Two electrodes individually contacting the two main body electrical contacts, and a dielectric material movable between the two electrodes and having a predetermined dielectric constant, wherein the dielectric material displays the process unit with the image. When the process unit is mounted on the main body of the image forming apparatus and is used, the unit is moved by a predetermined amount by the main body moving unit of the main body of the image forming apparatus according to the usage amount of the process unit detected by the unit usage amount detecting unit of the main body of the image forming apparatus. Thus, the amount of use of the process unit is stored in the process unit itself as the position of the dielectric, and the two power sources are stored. When the process unit is mounted on the image forming apparatus main body, the capacitance between the two electrodes is individually contacted with the two main body electrical contacts, and the capacitance between the two electrodes is measured by the main body measuring unit of the image forming apparatus main body. The process unit is measured as a value for determining the usage amount of the process unit.

According to another aspect of the present invention, there is provided a process unit configured to be detachable from a main body of an image forming apparatus, the process unit being capable of being sequentially exchanged according to the amount of use thereof. A moving frame that moves along a member, wherein when the process unit is mounted on the image forming apparatus main body and used, the unit usage amount detecting means of the image forming apparatus main body is used. Is moved by a predetermined amount by the main body moving means included in the image forming apparatus main body in accordance with the usage amount of the process unit detected by the processing unit. A process unit characterized by storing.

(Operation) In the above method of determining the storage of the used amount of the process unit, when the process unit is mounted on the image forming apparatus main body and used, the unit used amount detecting means detects the used amount of the process unit. By moving the dielectric by a predetermined amount by the main body moving means, the used amount of the process unit is stored in the process unit itself as the position of the dielectric, and when the process unit is mounted on the image forming apparatus main body, The capacitance between the two main body electrical contacts and the two electrodes that are individually in contact with each other is measured as a value by which the main body measuring means determines the amount of use of the process unit.

Further, in the above method of storing the used amount of a process unit, when the process unit is mounted on the image forming apparatus main body and used, the unit used amount detecting means detects the used amount of the process unit. By moving the moving frame by a predetermined amount by the main body moving means, the amount of use of the process unit is stored in the process unit itself as the position of the moving frame, and when the process unit is mounted on the image forming apparatus main body, a dielectric The body is moved to the position of the moving frame by the dielectric moving means, and the capacitance between the two electrodes is measured by the main body measuring means as a value for determining the used amount of the process unit.

In the above image forming apparatus, when the process unit is mounted on the image forming apparatus main body and used,
The amount of use of the process unit is stored in the process unit itself as the position of the dielectric by moving the dielectric by a predetermined amount by the main body moving unit according to the amount of use of the process unit detected by the unit use amount detection unit. Is done. Further, when the process unit is mounted on the image forming apparatus main body, the capacitance between the two main body electrical contacts and the two electrodes that are individually in contact with the main body measuring means is used for the main body measuring unit to determine the usage amount of the process unit. Measure as a value.

In the above image forming apparatus, when the process unit is mounted on the image forming apparatus main body and used, the moving frame is moved in accordance with the used amount of the process unit detected by the unit used amount detecting means. By moving the process unit by a predetermined amount, the used amount of the process unit is stored in the process unit itself as the position of the moving frame. Further, when the process unit is mounted on the image forming apparatus main body, the dielectric is moved to the position of the moving frame by dielectric moving means,
The capacitance between the two electrodes is measured as a value for determining the amount of use of the process unit by the main body measuring means.

In the above process unit, when the process unit is mounted on the main body of the image forming apparatus and used, the dielectric is moved by the main body moving means in accordance with the used amount of the process unit detected by the unit used amount detecting means. By performing the quantitative movement, the usage amount of the process unit is stored in the process unit itself as the position of the dielectric. Further, when the process unit is mounted on the image forming apparatus main body, the capacitance between the two electrodes that individually contact the two main body electrical contacts is used to determine the amount of use of the process unit by the main body measuring unit. It is measured as a value.

In the above process unit,
When the process unit is mounted on the image forming apparatus main body and used, the moving frame is moved by a predetermined amount by the main body moving unit according to the usage amount of the process unit detected by the unit usage amount detecting unit, so that the process The amount of use of the unit is stored in the process unit itself as the position of the moving frame.

[0026]

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

First Embodiment First, an overall configuration and an image forming process of an electrophotographic image forming apparatus (full color laser beam printer) according to this embodiment will be described with reference to FIG. FIG. 1 is a schematic configuration diagram of an electrophotographic image forming apparatus (full-color laser beam printer) of the present embodiment.

(Overall Configuration of Image Forming Apparatus and Image Forming Process) The electrophotographic image forming apparatus 20 shown in this embodiment is connected to a host such as a personal computer or a workstation. In response to a print request from the host 19, image data is received via the video interface. This image data is separated into four colors of yellow, magenta, cyan, and black.

In FIG. 1, reference numeral 1 denotes a drum-shaped electrophotographic photosensitive member (hereinafter referred to as a "photosensitive drum"), and an OPC (organic photoconductor) is used as the photosensitive member. The yellow, magenta, cyan, and black developing cartridges 4 (4a, 4b, 4c, 4d) are formed on a toner storage section (developer storage section) for storing toner (developer) and the photosensitive drum 1, respectively. Developing sleeves 5a and 5 for developing an electrostatic image (electrostatic latent image) to be developed with toner
The cartridges b, 5c and 5d (developing means) are integrated into a cartridge.

A yellow toner image is formed for the first color. The photosensitive drum 1 is uniformly charged by a charging roller 2 as a charging unit. Next, exposure is performed by the laser scanner 3 in accordance with the image signal. The laser scanner 3 scans the blinking of the semiconductor laser with a polygon scanner (not shown) and forms an image on the photosensitive drum 1 by an optical system. Thereby, an electrostatic image (electrostatic latent image) is formed on the photosensitive drum 1. This electrostatic image is developed and visualized by a yellow developing cartridge 4 a arranged in the rotary 6. At this time, a jumping development is performed by applying a developing bias in which a DC voltage and an AC voltage are superimposed on the developing sleeve 5a.

The visualized toner image is pressed against the photosensitive drum 1 with a predetermined pressing force, and is transferred (primary transfer) onto the surface of the intermediate transfer body 7 rotating at a constant speed at the process speed.
At this time, a transfer voltage having a polarity opposite to the charge polarity of the toner is applied.

The toner remaining on the photosensitive drum 1 without being primary-transferred is scraped off by a cleaning blade 8 as a cleaning means and collected in a cleaner container 9.

The above process is repeated for the remaining three colors (magenta, cyan,
Black) is repeated in the same manner, and each time, the toner images of the toners contained in the developing cartridges 4b, 4c, and 4d of each color are sequentially transferred to the surface of the intermediate transfer body 7,
A full-color toner image is formed.

The transfer voltage of the full-color toner image on the intermediate transfer member 7 is opposite to the transfer voltage of the toner.
, The recording paper fed from a multi-feeder (not shown), an OHP,
Batch transfer (secondary transfer) is performed on a medium 12 as a recording medium such as a sheet or cloth.

The intermediate transfer member 7 is not transferred at the time of the secondary transfer.
The toner remaining on the upper surface is charged by the cleaning roller 10 to a polarity opposite to the charging polarity of the toner. Next, the toner image is re-transferred onto the photosensitive drum 1 as the intermediate transfer member 7 rotates, and is collected in the cleaner container 9 by the cleaning blade 8.

The full-color toner image transferred to the medium 12 is permanently fixed by applying heat and pressure by a fixing roller (fixing means) 11, and the discharge roller 1
It is discharged out of the machine by 5a, 15b and 15c. Therefore, a desired print image is obtained.

The image forming apparatus 20 of this embodiment is a process unit that integrates the photosensitive drum 1, the charging roller 2, the cleaning blade 8, and the cleaner container 9 as a process unit that can be attached to and detached from the image forming apparatus main body 20a. A photosensitive drum cartridge 16 as a cartridge, rotary yellow, magenta, and cyan color developing cartridges 4a, 4b, and 4c containing non-magnetic toner (developer) disposed in the rotary 6 and a magnetic toner (developer) ) Containing a fixed black developing cartridge 4
d, an intermediate transfer member cartridge 17 integrally including the intermediate transfer member 7, and a fixing cartridge 18 integrally including the fixing roller 12. Here, the photosensitive drum cartridge 16 is detachably mounted on a cartridge mounting guide (not shown) as mounting means provided on the image forming apparatus main body 20 a above the intermediate transfer body 7. The developing cartridges 4a, 4b, and 4c are rotatably mounted on the image forming apparatus main body 20a and removably mounted on a cartridge mounting guide (not shown) provided on the rotary 6 as mounting means. The developing cartridge 4d is removably mounted above the rotary 6 on a cartridge mounting guide (not shown) as mounting means provided on the image forming apparatus main body 20a. The intermediate transfer cartridge 18 is located below the photosensitive drum cartridge 16 in the image forming apparatus main body 2.
It is removably mounted on a cartridge mounting guide (not shown) as mounting means provided in Oa. Then, the fixing cartridge 18 is attached to the intermediate transfer unit 18.
In the conveyance path of the medium 12 conveyed from the side, it is detachably mounted to a cartridge mounting guide (not shown) as mounting means provided in the image forming apparatus main body 20a.

(Explanation of Configuration for Storing Usage of Process Unit) Next, the configuration for determining the storage of usage of the process unit will be described with reference to FIGS. 2 and 3. FIG. In the present embodiment, a case will be described in which the usage amount storage determination configuration of the process unit is applied to a photosensitive drum cartridge.

In the photosensitive drum cartridge usage detecting method for detecting the usage of the photosensitive drum cartridge 16 according to the present embodiment, the photosensitive drum rotation time and the time during which an AC bias is applied to the charging roller are determined in advance. The method of converting into the amount of use by the conversion formula is used.

More specifically, as shown in FIG. 2, the rotation operation of the photosensitive drum 1 is controlled by a photosensitive member rotation instructing unit 24, and the charging roller 2 serving as a contact charging member is appropriately supplied from a bias applying power source 23. The AC bias and the DC bias are independently controlled and applied by the AC bias output instruction unit 21 and the DC bias output instruction unit 22, respectively.

The AC bias output instructing section 21 and the photosensitive drum rotation instructing section 24 are connected to a photosensitive drum use amount detecting section 25 as a unit use amount detecting means. The photosensitive drum rotation time Tdr is detected. Then, it is converted into photoconductor usage amount information D by a predetermined conversion formula D = k1 × Tac + k2 × Tdr.

As shown in FIG. 3, the photosensitive drum cartridge 16 has two electrodes inside a hole 9a1 (see FIG. 4) provided in the side surface 9a of the cleaner container 9 on the side of the image forming apparatus main body 20a. Conductor plates 31, 32 are arranged in parallel. The hole 9a has a depth at least about twice as long as the length (hereinafter referred to as "vertical") 10 of the conductive plates 31 and 32 in the longitudinal direction (axial direction of the photosensitive drum). Length in the width direction (hereinafter referred to as "horizontal")
It is formed so as to be a rectangular parallelepiped space having substantially the same width dimension as m0 (see FIG. 4). The conductor plates 31 and 32 are provided outside the cleaner container 9 with electrical contacts 31a and 32, respectively.
a and can be contacted with electrical contacts 31b and 32b on the image forming apparatus main body 20a side described later.

Inside the hole 9a, both the conductor plates 31, 32 are provided.
A dielectric 35 having a predetermined dielectric constant .epsilon. The dielectric 35 is formed by a vertical length l0 and a horizontal length m0 of the conductive plates 31 and 32.
It is formed in the shape of a rectangular parallelepiped having the same dimensions as the above, and at least the surface facing the window 34 described later is colored. Dielectric 3
5, a screw hole 35a extending in parallel with the conductor plates 31 and 32 is provided at the center. The screw hole 35a has a screw portion on the outer periphery and is rotatably supported by the cleaner container 9 so as to be rotatable. Are screwed into each other. As a result, the rotation of the rotating shaft 36 in the dielectric 35 is prevented by the rotation of the rotating shaft 36 on the wall surfaces of the conductor plates 31 and 32 and the hole 9a. It can be moved only in the direction parallel to.

The cleaner container 9 is provided with a transparent acrylic window 34 on the outer wall surface 9b adjacent to the side surface 9a on which the conductor plates 31, 32 and the dielectric 35 are provided. The window 34 has the same length as the vertical length l0 of the dielectric 35 from the edge on the side surface 9a side of the outer wall surface 9b. This allows the user to check the movable width (range) of the colored dielectric 35 and the current position of the dielectric 35.

The conductive plate 3 is attached to the image forming apparatus main body 20a.
Electrical contacts (main body electrical contacts) 31b and 32b capable of contacting the 1 and 32 electrical contacts 31a and 32a are provided. The capacitance between the conductive plates 31 and 32 is determined by the image forming apparatus main body 20a.
A constant voltage from an AC power supply 38 provided at the
It can be obtained by measuring the current value when applied between 1b and 32b by the detector (main body measuring means) 39.

The image forming apparatus main body 20a is provided with a rotating shaft driving means 37 for rotating the rotating shaft 36 on the photosensitive drum cartridge 16 side. The rotating shaft driving means 37 controls the number of steps of a stepping motor (not shown) in accordance with the usage information D of the photosensitive drum cartridge 16 provided by the photosensitive drum usage detecting unit 25, and adjusts the center of the dielectric 35. The penetrating rotating shaft 36 is rotated.

In this case, the life of the photosensitive drum cartridge 16 is 50,000 images in terms of A4 size paper. This value is determined by the thickness of the photosensitive drum and the amount of abrasion of the drum per image, and is not limited thereto. Subsequent photosensitive drum cartridge 16
Is a cause of a defective image and is incompatible with usability.

When the photosensitive drum cartridge 16 is inserted into the image forming apparatus main body 20a to a predetermined mounting position, the electrical contacts 31a and 32a of the conductive plates 31 and 32 and the electrical contacts 31b and 32b of the image forming apparatus main body always maintain conduction. At the same time, the rotating shaft 36 penetrating the center of the dielectric 35 and the rotating shaft driving means 37 provided in the image forming apparatus main body 20a are fitted.

FIG. 4 shows the positional relationship between the conductor plates 31, 32 and the dielectric 35 in a new photosensitive drum cartridge 16.
(A).

The conductor plates 31 and 32 face each other in parallel while maintaining the interval d0, and have an area S0 with a length l0 and a width m0. The surface of the dielectric 35 having a dielectric constant .epsilon.1 facing each of the conductor plates 31 and 32 also has an area S0 of length l0 and width m0.
At this time, the capacitance CNEW between the conductor plates 31 and 32 is determined when a constant voltage from an AC power supply 38 provided in the image forming apparatus main body 20a is applied between the electric contacts 31b and 32b.
The current value can be obtained by measuring the current value with the detector 39, and is represented by the following equation.

CNEW = ε1 × S0 / d0 FIG. 4 shows the positional relationship between the conductor plates 31, 32 and the dielectric 35 in the photosensitive drum cartridge 16 when an X image is formed in the image forming apparatus 20 of this embodiment. (B) of FIG.

By this time, the rotating shaft driving means 37 has
Based on the usage information D of the photosensitive drum cartridge 16 calculated from the photosensitive drum rotation time and the time when the AC bias is applied to the charging roller 2, the stepping motor is rotated by X steps corresponding to the X image. Therefore,
The rotation of the rotating shaft 36 passing through the center of the dielectric 35 fitted to the rotating shaft driving means 37 also causes the dielectric 35 to move a distance lX in the direction of arrow A in parallel with the conductor plates 31 and 32.

The capacitance CX between the conductor plates 31 and 32 at this time is expressed as the sum of the capacitances of the range (1) where the dielectric 35 having the dielectric constant ε1 exists and the range (2) where the dielectric 35 does not exist. When the dielectric constant of air is ε0, S1 = (10−1X) × m0 C1 = ε1 × S1 / d0 S2 = 1 ×× m0 C2 = ε0 × S1 / d0 CX = C1 + C2

FIG. 4C shows the positional relationship between the conductor plates 31, 32 and the dielectric 35 at the time when an image of 50,000 images, which is the life, is formed.

50,000 equivalent to 50,000 images
By rotating the stepping motor by the amount of the step, the dielectric 35 moves a distance l0 in the direction of arrow A in parallel with the conductor plates 31 and 32. Therefore, the dielectric 35 does not exist between the conductor plates 31 and 32. The capacitance CEND at this time is expressed by the following equation.

CEND = ε0 × S0 / d0 FIG. 7 shows a change in the capacitance between the conductor plates 31 and 32 according to the amount of use of the photosensitive drum cartridge 16 from the beginning to the end of its life. Each time an image is formed, the rotating shaft driving means 3
Since the stepping motor 7 rotates by a predetermined amount and the dielectric 35 also moves by a predetermined amount, the change in capacitance becomes a linear function of the number of times of image formation, that is, the usage amount of the photosensitive drum cartridge. That is, for the usage amount X of the photosensitive drum cartridge 16, the capacitance is always the predetermined value CX.

A transparent acrylic window 34 is provided on the outer wall surface 9b of the cleaner container 9 of the photosensitive drum cartridge 16.
Is provided so that the position of the colored dielectric 35 can be visually checked. Therefore, when the user removes the photosensitive drum cartridge 16 from the image forming apparatus main body 20a, the user can easily check the usage amount of the photosensitive drum cartridge 16 from the beginning to the end of its life by visually checking the position of the dielectric 35 through the window 34. Can be.

When the user again inserts the photosensitive drum cartridge 16 into the image forming apparatus main body 20a to a predetermined mounting position, the photosensitive drum cartridge 1
Since the electrical contacts 31a and 32a of the sixth conductive plates 31 and 32 contact the electrical contacts 31b and 32b of the image forming apparatus main body 20a, a constant voltage can be applied between the conductive plates 31 and 32 from the AC power supply 38. Becomes Then, the current value between the electric contacts 31b and 32b when the AC power supply 38 applies a constant voltage between the conductive plates 31 and 32, that is, the capacitance between the conductive plates 31 and 32 is measured by the detector 39. Then, the used amount of the photosensitive drum cartridge 16 at the time when the photosensitive drum cartridge 16 is removed from the image forming apparatus main body 20a is detected, and a control unit (CPU) (not shown) of the image forming apparatus main body 20a based on the detected amount.
Captures as usage information D for determining the usage of the photosensitive drum cartridge 16. This is also effective when a user uses a plurality of photosensitive drum cartridges 16.

At this time, when it is detected that the electrostatic capacity is within the range of a predetermined value CY% to CEND after Y% of 50,000 images, which is the life of the photosensitive drum cartridge 16, a warning prompting replacement is issued. The control unit outputs the data to a display unit (not shown) provided in the image forming apparatus main body 20a.

As described above, the usage amount of the photosensitive drum cartridge 16 at the time when the photosensitive drum cartridge 16 is removed from the image forming apparatus main body 20a is detected, and the usage amount information D of the photosensitive drum cartridge 16 is detected.
When the photosensitive drum cartridge 16 is removed from the image forming apparatus main body 20a and when a plurality of photosensitive drum cartridges 16 are used, it is possible to reliably output a warning prompting replacement and detect the cartridge life. Become.

As described above, the embodiment in which the used amount of the photosensitive drum cartridge 16 is stored and discriminated is described as the parallel plate electrodes 31 and 3.
Although the description has been given of the rectangular parallelepiped dielectric body 35 sandwiched between the two, the shapes of the electrodes 31 and 32 and the dielectric body 35 are not limited to this. The photosensitive drum cartridge usage amount detection method includes the photosensitive drum rotation time and charging roller 2
Although the method of converting the time during which the C bias is applied into the amount of use by a predetermined conversion formula is used, the present invention is not limited to this. Further, the usage amount storage determination configuration of the present embodiment can be widely applied to storage determination of the usage amount of a developing cartridge, an intermediate transfer cartridge, a fixing cartridge, and the like as a process unit. It is possible to select the most appropriate method.

As described above, in the present embodiment, the two main unit electrical contacts (the photosensitive drum cartridge 16) of the image forming apparatus main body 20a are attached to the process unit (photosensitive drum cartridge 16) that is detachable from the image forming apparatus main body 20a. Two electrodes (conductive plates 31, 32) that individually contact the electrical contacts 31b, 32b), and are movable between the two electrodes;
In addition, since the dielectric 35 having a predetermined dielectric constant is provided, the dielectric is determined according to the amount of use of the process unit detected by the unit usage detecting means (photosensitive drum usage detecting unit 25) of the image forming apparatus main body 20a. By moving the body 35 by a predetermined amount by the main body moving means (rotary axis driving means 37), the used amount of the process unit can be stored in the process unit itself as the position of the dielectric 35.
Further, when the process unit is mounted on the image forming apparatus main body 20a, the capacitance between the two electrodes that individually make contact with the two main body electrical contacts is measured by the main body measuring means (detector 39) of the image forming apparatus main body 20a. It can be measured as a value for determining the usage of the process unit.
Thus, the use amount of the process unit can be stored in the process unit itself irrespective of whether the process unit is replaced and used, and the use amount of the process unit can be determined in the image forming apparatus main body 20a.

Further, since the movable width of the dielectric 35 and the position of the dielectric 35 within the movable width can be confirmed, the user can easily use the cartridge when removing the process unit. You can check.

[Second Embodiment] Next, a configuration for determining the storage of used amount of a process unit according to this embodiment will be described with reference to FIGS. 5 and 6. FIG.

(Explanation of Structure of Discriminating Use Amount of Process Unit) In the present embodiment, a case where the structure of discriminating the use amount of a process unit is applied to a photosensitive drum cartridge will be described. In the present embodiment, the electrodes and dielectrics provided on the photosensitive drum cartridge in the image forming apparatus of Embodiment 1 described above are provided on the image forming apparatus main body side,
The photosensitive drum cartridge is characterized in that only moving frames that move in accordance with the amount of cartridge used are provided.

FIG. 5 is a schematic diagram of a configuration for determining the usage amount storage of the photosensitive drum cartridge according to the present embodiment. Note that the same parts as those described in the first embodiment are denoted by the same reference numerals, and description thereof will be omitted.

At a predetermined position of the photosensitive drum cartridge 16, a moving frame 40 is provided. Moving piece 40
Is moved along the rotation shaft 36 by rotating the rotation shaft (guide member) 36. The position of the moving piece 40 can be confirmed from a transparent acrylic window 34 provided on the outer wall surface 9b of the cleaner container 9.

The image forming apparatus main body 20a has a conductive plate 4
1, 42 are disposed in parallel, and the two conductive plates 41, 4
Between them, a dielectric 43 is arranged. The dielectric 43 is formed in a rectangular parallelepiped shape having the same dimensions as the length l0 and width m0 of the conductive plates 41 and 42 (see FIG. 6). The dielectric 43 has a through hole 43a at the center, which extends in parallel with the conductor plates 41 and 42 and through which a rotating shaft driving means 37 to be described later penetrates.

The rotary shaft driving means 37 is fitted to the rotary shaft 36 by inserting the photosensitive drum cartridge 16 into the image forming apparatus main body 20a to a predetermined mounting position. Rotating shaft 36
Since the radius of the rotating shaft driving unit 37 is smaller than the radius of the through hole 43 a of the dielectric 43, the rotation of the rotating shaft 36 and the rotating shaft driving unit 37 is not transmitted to the dielectric 43.

A spring (dielectric moving means) 44 is disposed at the end of the dielectric 43 on the image forming apparatus main body 20a side. The spring 44 is fitted on the rotating shaft driving means 37 and constantly biases the dielectric 43 toward the photosensitive drum cartridge 16. Accordingly, as shown in FIG. 6A, the dielectric 43 comes into contact with the moving piece 40 in a state where the photosensitive drum cartridge 16 is mounted at a predetermined mounting position, so that a load from the photosensitive drum cartridge 16 is reduced. In addition, it is pushed into the image forming apparatus main body 16 side. Photosensitive drum cartridge 16
When no is inserted, no load is applied.
The dielectric 43 protrudes from the image forming apparatus main body 20a.

The capacitance between the conductive plates 41 and 42 can be obtained by measuring a current value when a constant voltage is applied from the AC power supply 38.

FIG. 6A shows the positional relationship among the conductive plates 41 and 42, the moving piece 40, and the dielectric 43 when a new photosensitive drum cartridge is inserted into the image forming apparatus main body 20a to a predetermined mounting position. .

This positional relationship is equal to the positions of the conductive plates 31 and 32 and the dielectric 35 in the new photosensitive drum cartridge 16 of the first embodiment. Therefore, the conductive plates 41, 4
The capacitance CNEW between the two is represented by the following equation.

CNEW = ε1 × S0 / d0 FIG. 5 shows the positional relationship between the conductive plates 41 and 42 and the dielectric 43 in the photosensitive drum cartridge 16 when an X image is formed in the image forming apparatus 20 of this embodiment. 5B and FIG. 5C shows the positional relationship between the conductive plates 41 and 42 and the dielectric 43 at the time when an image of 50,000 images, which is the life, is formed.

In this case, the positional relationship between the conductive plates 31, 32 and the dielectric 35 of the respective image forming sheets in the first embodiment is the same. Therefore, the capacitances C1,
C2 is represented by the following equation.

S1 = (10-1X) × m0 C1 = ε1 × S1 / d0 S2 = 1X × m0 C2 = ε1 × S1 / d0 CX = C1 + C2 CEND = ε0 × S0 / d0 Life of the photosensitive drum cartridge 16 from the beginning The change in the capacitance between the conductor plates 41 and 42 according to the used amount up to this point is also the same as the graph of FIG. 7 shown in the first embodiment, and the description thereof is omitted.

Also, in the present embodiment, a transparent acrylic window 34 is provided on the outer wall surface 9b of the cleaner container 9 of the photosensitive drum cartridge 16 in the same manner as in the first embodiment. The position can be seen visually. Therefore, when the user removes the photosensitive drum cartridge 16 from the image forming apparatus main body 20a, the user can easily check the usage amount of the photosensitive drum cartridge 16 from the beginning to the end of its life by visually checking the position of the moving frame 40 through the window 34. Can be.

When the user again inserts the photosensitive drum cartridge 16 into the image forming apparatus main body 20a to a predetermined mounting position, the AC power supply 38
The current value when a constant voltage is applied between the photosensitive drums 1 and 42, that is, the capacitance between the conductive plates 41 and 42 is measured by the detector 39, and the photosensitive drum at the time when the photosensitive drum is removed from the image forming apparatus main body 20a is measured. Detects the amount of cartridge 16 used,
Based on the value, a control unit (CPU) (not shown) of the image forming apparatus main body 20a takes in the usage information D for determining the usage of the photosensitive drum cartridge 16. This is also effective when a user uses a plurality of photosensitive drum cartridges 16.

At this time, at Y% or later of 50,000 images, which is the life of the photosensitive drum cartridge,
When the capacitance is detected to be in the range of the predetermined value CY% to CEND, the control unit outputs a warning prompting replacement to a display unit (not shown) provided in the image forming apparatus main body 20a.

As described above, the usage amount of the photosensitive drum cartridge 16 at the time when the photosensitive drum cartridge 16 is removed from the image forming apparatus main body 20a is detected, and the usage amount information D of the photosensitive drum cartridge 16 is detected.
When the photosensitive drum cartridge 16 is removed from the image forming apparatus main body 20a and when a plurality of photosensitive drum cartridges 16 are used, it is possible to reliably output a warning prompting replacement and detect the cartridge life. Become.

As described above, the embodiment in which the used amount of the photosensitive drum cartridge 16 is stored and discriminated is described as the parallel plate electrodes 41 and 4.
Although the description has been given of the rectangular parallelepiped dielectric 43 sandwiched between the two, the shapes of the electrodes 41 and 42 and the dielectric 43 are not limited thereto. The photosensitive drum cartridge usage amount detection method includes the photosensitive drum rotation time and charging roller 2
Although the method of converting the time during which the C bias is applied into the amount of use by a predetermined conversion formula is used, the present invention is not limited to this. Further, the usage amount storage determination configuration of the present embodiment can be widely applied to storage determination of the usage amount of a developing cartridge, an intermediate transfer cartridge, a fixing cartridge, and the like as a process unit. It is possible to select the most appropriate method.

As described above, in this embodiment, the process unit (photosensitive drum cartridge 16) detachable from the image forming apparatus main body 20a, the guide member (rotary shaft 36), and the guide member Since the moving frame 40 is provided along with the moving frame 40, the moving frame 40 is moved according to the amount of use of the process unit detected by the unit usage detecting means (photosensitive drum usage detecting section 25) of the image forming apparatus main body 20a. The amount of use of the process unit can be stored in the process unit itself as the position of the moving piece 40 by moving the process unit by a predetermined amount by the main body moving unit (rotation axis driving unit 37). The image forming apparatus main body 20a includes a unit usage detecting unit (photosensitive drum usage detecting unit 25) for detecting the usage of the process unit, and a moving frame 40 of the process unit.
Body moving means (rotation axis driving means 3) for moving
7), two electrodes (conductive plates 41 and 42), a dielectric 43 movable between the two electrodes and having a predetermined dielectric constant, and the dielectric 43 to the position of the moving piece 42 of the process unit. Since a dielectric moving means (spring 44) for moving the body 43 and a main body measuring means (detector 39) for measuring the capacitance between the two electrodes are provided, the process unit can be imaged. When attached to the forming apparatus main body 20a, the dielectric 43 of the image forming apparatus main body 20a is moved to the position of the moving frame 40 by the dielectric moving means, and the electrostatic capacity between the two electrodes is reduced by the main body measuring means. It can be measured as a value for determining the usage of the process unit. Thus, the usage amount of the process unit can be stored in the process unit itself irrespective of whether the process unit is replaced or used, and the usage amount of the process unit is stored in the image forming apparatus main body 20a.
Can be determined.

Further, since the movable width of the dielectric 35 and the position of the dielectric 35 within the movable width can be confirmed, the user can easily use the cartridge when removing the process unit. You can check.

The moving unit 40 is provided in the process unit.
And the electrodes and the dielectric 43 are attached to the image forming apparatus main body 2.
By arranging the process unit on the 0a side, usability such as making the process unit less expensive and not touching the electrodes can be achieved.

In both the first and second embodiments, it is not necessary to attach a storage element such as an EEPROM and a connector for accumulating and storing the amount of use of the process unit to each process unit, and the storage information due to noise or the like is not required. No electrostatic noise countermeasures are required around the image forming apparatus main body and the storage element of the process unit to prevent the destruction of the process unit, and a mechanism that prevents the process unit from being taken out when writing information is also unnecessary. This has the effect of simplifying the configuration for storage usage determination.

In the first and second embodiments, the photosensitive drum cartridge as a process cartridge, which is an example of the process unit, has a charging unit, a cleaning unit, and an electrophotographic photosensitive member integrally formed as a cartridge. One of the charging unit and the cleaning unit and the electrophotographic photosensitive member may be integrally formed into a cartridge, and the cartridge may be configured to be detachable from the image forming apparatus main body.

[0087]

As described above, according to the method for determining the amount of use of a process unit according to the present invention, the amount of use of a process unit can be stored in the process unit itself irrespective of whether the process unit is replaced or not. The used amount of the process unit can be determined in the image forming apparatus main body.

Further, according to the image forming apparatus of the present invention, the usage amount of the process unit can be stored in the process unit itself irrespective of whether the process unit is replaced or not.
The used amount of the process unit can be determined in the image forming apparatus main body.

Further, the process unit of the present invention can store the used amount of the process unit in the process unit itself, regardless of whether the process unit is used for replacement or not. Can be determined. To provide a unit.

Further, the process unit of the present invention can store the used amount of the process unit in the process unit itself irrespective of whether the process unit is replaced with the image forming apparatus main body.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram of a main part of an image forming apparatus according to a first embodiment of the present invention.

FIG. 2 is an explanatory diagram of a usage amount storage determination configuration of a process unit according to the first embodiment.

FIG. 3 is an explanatory diagram of a usage amount storage determination configuration of a process unit according to the first embodiment.

4A is an explanatory diagram of a dielectric position of a new photosensitive drum cartridge, FIG. 4B is an explanatory diagram of a dielectric position of a photosensitive drum cartridge on which an X image image is formed, FIG.
(C) is an explanatory diagram of the dielectric position of the photosensitive drum cartridge at the end of its life.

FIG. 5 is an explanatory diagram of a usage amount storage determination configuration of a process unit according to a second embodiment.

6A is an explanatory diagram of a dielectric position of a new photosensitive drum cartridge, FIG. 6B is an explanatory diagram of a dielectric position of a photosensitive drum cartridge on which an X image image has been formed, FIG.
(C) is an explanatory diagram of the dielectric position of the photosensitive drum cartridge at the end of its life.

FIG. 7 is an explanatory diagram showing the relationship between the capacitance and the usage amount of the photosensitive drum cartridge.

[Explanation of symbols]

 1 photosensitive drum 2 charging roller 4 developing cartridge 5 developing sleeve 7 intermediate transfer member 8 cleaning blade 11 fixing roller 12 media 16 photosensitive drum cartridge 17 intermediate Transfer Cartridge 18 Fixing Cartridge 20 Image Forming Apparatus 20a Image Forming Apparatus Main Body 25 Photosensitive Drum Usage Amount Detector 31 Conductor Plate 32 Conductor Plate 31b Electrical Contact 32b Electrical Contact 35 {Dielectric 36} Rotating axis 37} Rotating axis driving means 40} Moving piece 41} Conductor plate 42} Conductor plate 43} Dielectric

Continued on the front page F-term (reference) 2H027 DA44 DE02 DE04 ED01 ED03 ED08 ED24 ED25 ED27 GA05 GB01 HB02 HB14 HB15 2H071 BA13 BA14 BA19 BA20 BA33

Claims (17)

[Claims] A process unit configured to be detachable from a main body of the image forming apparatus, the process unit having a process unit that can be sequentially replaced according to a usage amount, and used in an image forming apparatus for forming an image on a recording medium. In the usage amount storage determination method, the process unit includes two electrodes that individually contact two main body electrical contacts of the image forming apparatus main body,
A dielectric member movable between the two electrodes and having a predetermined dielectric constant; and a unit included in the image forming apparatus main body when the process unit is mounted on the image forming apparatus main body and used. By moving the dielectric by a predetermined amount by a main body moving unit of the image forming apparatus main body in accordance with the used amount of the process unit detected by the amount detecting unit,
The amount of use of the process unit is stored in the process unit itself as the position of the dielectric, and the two electrodes individually contact the two main body electrical contacts when the process unit is mounted on the image forming apparatus main body. A method of storing the amount of use of the process unit, wherein the capacitance between the process units is measured by a main body measuring unit of the main body of the image forming apparatus as a value for determining the amount of use of the process unit. 2. A process cartridge which is configured to be detachable from an image forming apparatus main body and has a process unit which can be sequentially replaced according to the amount of use thereof, and which is used in an image forming apparatus for forming an image on a recording medium. Wherein the process unit has a guide member and a moving piece that moves along the guide member, wherein the image forming apparatus main body is configured to detect a use amount of the process unit. A unit use amount detecting unit, a main body moving unit for moving the moving frame of the process unit, two electrodes, a dielectric body movable between the two electrodes, and having a predetermined dielectric constant; Dielectric moving means for moving the dielectric to the position of the moving frame of the process unit, and measuring capacitance between the two electrodes A main body measuring unit for mounting the process unit on the main body of the image forming apparatus, and the moving frame according to the used amount of the process unit detected by the unit used amount detecting unit. Is moved by a predetermined amount by the main body moving means, so that the used amount of the process unit is stored in the process unit itself as the position of the moving frame. When the process unit is mounted on the image forming apparatus main body, the dielectric Moving the body to the position of the moving frame by the dielectric moving means, and measuring the capacitance between the two electrodes as a value for determining the amount of use of the process unit by the main body measuring means. A method for determining the amount of usage of a process unit. 3. An image forming apparatus for forming an image on a recording medium having a process unit which is detachably attached to a main body of the image forming apparatus and which can be sequentially replaced according to the amount of use of the main body. A contact; two electrodes individually contacting the two power supply contacts; and a mounting for detachably mounting a process unit having a dielectric movable between the two electrodes and having a predetermined dielectric constant. Means for detecting the amount of use of the process unit when the process unit is mounted on the image forming apparatus main body and used, and for moving the dielectric of the process unit. A main body moving means for measuring a capacitance between the two electrodes of the process unit individually contacting the two main electric contacts; And a main body measuring unit, wherein the main body moving unit moves the dielectric by a predetermined amount according to the usage amount of the process unit detected by the unit usage amount detecting unit, so that the usage amount of the process unit is Is stored in the process unit itself as the position of the dielectric, and the main body measuring unit is configured to detect the position of the process unit that individually contacts the two main body electrical contacts when the process unit is mounted on the image forming apparatus main body. An image forming apparatus, wherein an electrostatic capacity between the two electrodes is measured as a value for determining a usage amount of the process unit. 4. An image forming apparatus for forming an image on a recording medium, comprising: a process unit which is detachably attached to an image forming apparatus main body and has a process unit which can be sequentially replaced according to the amount of use of the guide unit; Mounting means for removably mounting a process unit having a movable frame moving along the guide member; and an amount of use of the process unit when the process unit is mounted on the image forming apparatus main body and used. Unit use amount detecting means for detecting the position, body moving means for moving the moving frame of the process unit, two electrodes, movable between the two electrodes, and having a predetermined permittivity. A dielectric moving means for moving the dielectric to a position of the moving frame of the process unit; And a main body measuring means for measuring the capacitance between the electrodes, wherein the main body moving means determines the moving frame in accordance with the used amount of the process unit detected by the unit used amount detecting means. By moving the process unit, the amount of use of the process unit is stored in the process unit itself as the position of the moving frame, and the dielectric moving unit is configured to mount the process unit on the image forming apparatus main body when the process unit is mounted on the image forming apparatus main body. The body is moved to the position of the moving piece, and the main body measuring unit determines the capacitance between the two electrodes in a state where the dielectric has moved to the position of the moving piece, and determines the amount of use of the process unit. An image forming apparatus characterized in that it is measured as a value for the image forming apparatus. 5. The process unit according to claim 1, wherein the electrophotographic photosensitive member and a process unit acting on the electrophotographic photosensitive member are integrally formed into a cartridge, and the cartridge is detachably mountable to the image forming apparatus main body. 5. The cartridge according to claim 3, wherein the cartridge is a cartridge.
An image forming apparatus according to claim 1. 6. The process cartridge, wherein at least one of a charging unit for charging the electrophotographic photosensitive member and a cleaning unit for removing a developer remaining on the electrophotographic photosensitive member, as the processing unit. One and the electrophotographic photoreceptor are integrally made into a cartridge,
The image forming apparatus according to claim 5, wherein the cartridge is detachable from the image forming apparatus main body. 7. The process unit includes: a developer accommodating section for accommodating a developer used for developing an electrostatic latent image formed on the electrophotographic photosensitive member; and a developer accommodating portion formed on the electrophotographic photosensitive member. 4. A developing cartridge in which a developing unit for developing an electrostatic latent image with a developer is integrally formed as a cartridge, and the cartridge is detachably mountable to the image forming apparatus main body. Alternatively, the image forming apparatus according to claim 4. 8. The process unit is formed as a unit having an intermediate transfer member onto which a developer image obtained by developing an electrostatic latent image formed on an electrophotographic photosensitive member with a developer is transferred. The image forming apparatus according to claim 3, wherein the image forming apparatus is an intermediate transfer unit that is detachable from a main body of the image forming apparatus. 9. A fixing means for fixing the developer image to the recording medium on which a developer image obtained by developing an electrostatic latent image formed on an electrophotographic photosensitive member with a developer is transferred. The image forming apparatus according to claim 3, wherein the image forming apparatus is a fixing unit that is unitized to include a unit, and that is detachable from the image forming apparatus main body. 10. A process unit that is detachably attached to an image forming apparatus main body and that can be sequentially replaced according to the amount of use thereof, comprising: two electrodes that individually contact two main body electrical contacts of the image forming apparatus main body; A dielectric that is movable between the two electrodes and has a predetermined dielectric constant, wherein the dielectric forms the image when the process unit is mounted on the image forming apparatus main body. The amount of use of the process unit is moved by a predetermined amount by a main body moving unit of the image forming apparatus main body in accordance with the amount of use of the process unit detected by the unit usage amount detection unit of the apparatus main body. The two electrodes store the process unit in the main body of the image forming apparatus. And the capacitance between the two electrodes is measured as a value for determining the amount of use of the process unit by the main body measuring means of the main body of the image forming apparatus. Process unit characterized by being performed. 11. A process unit configured to be detachable from the image forming apparatus main body and replaceable sequentially according to the amount of use thereof, comprising: a guide member; and a moving piece moving along the guide member. When the process unit is mounted on the image forming apparatus main body and used, the moving frame is used for the image forming in accordance with the used amount of the process unit detected by the unit usage detecting means of the image forming apparatus main body. A process unit wherein the used amount of the process unit is stored in the process unit itself as the position of the moving frame by being moved by a predetermined amount by the main body moving means of the apparatus main body. 12. The movable member according to claim 1, wherein a movable range of the movable member and a position of the movable member within the movable range of the movable member are visible from outside.
A process unit according to claim 11 or claim 12. 13. The process unit according to claim 1, wherein the electrophotographic photosensitive member and a process unit acting on the electrophotographic photosensitive member are integrally formed into a cartridge, and the cartridge is detachable from the image forming apparatus main body. The process unit according to claim 10, wherein the process unit is a cartridge. 14. The process cartridge, wherein the process unit is at least one of a charging unit for charging the electrophotographic photosensitive member and a cleaning unit for removing a developer remaining on the electrophotographic photosensitive member. 14. The process unit according to claim 13, wherein one of the electrophotographic photosensitive members is integrally formed as a cartridge, and the cartridge is detachably mountable to the image forming apparatus main body. 15. The electrophotographic photosensitive member according to claim 15, wherein the process unit includes a developer accommodating portion for accommodating a developer used for developing an electrostatic latent image formed on the electrophotographic photosensitive member. 11. A developing cartridge in which a developing unit for developing an electrostatic latent image with a developer is integrally formed as a cartridge, and the cartridge is detachably mountable to the image forming apparatus main body. Alternatively, the process unit according to claim 11. 16. The process unit is formed as a unit having an intermediate transfer member on which a developer image obtained by developing an electrostatic latent image formed on an electrophotographic photosensitive member with a developer is transferred.
12. The process unit according to claim 10, wherein the unit is an intermediate transfer unit that is detachable from the image forming apparatus main body. 17. A fixing unit for fixing the developer image to the recording medium on which a developer image obtained by developing an electrostatic latent image formed on an electrophotographic photosensitive member with a developer is transferred. The process unit according to claim 10, wherein the process unit is a fixing unit that is unitized to include a unit, and is detachable from the image forming apparatus main body.