JP2002328519A - Image forming device, electrophotographic image forming device and process cartridge - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an image forming device, an electrophotographic image forming device and a process cartridge improved in terms of developer amount detecting accuracy. SOLUTION: This image forming device is provided with a developer storage part 23d in which developer is stored, a 1st developer amount detecting means consisting of a plurality of electrodes 23a and 41 arranged in the storage part 23d, a 1st electrostatic capacity detecting means 61 for detecting electrostatic capacity between the plurality of electrodes of the 1st developer amount detecting means, and a 1st developer amount conversion means 50 for converting the detected result by the detecting means 61 into developer amount, and is constituted so that the developer amount in the storage part 23d is detected by correcting the converted result by the conversion means 50 in accordance with the detected result by the detecting means 61 in specified timing.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image forming apparatus provided with a developer amount detecting device capable of detecting a developer amount,
The present invention relates to an electrophotographic image forming apparatus and a process cartridge.

Here, as an electrophotographic image forming apparatus,
For example, an electrophotographic copying machine, an electrophotographic printer (for example,
LED printers, laser beam printers, etc.), and electrophotographic facsimile machines.

A process cartridge is a cartridge in which at least one of a charging unit, a developing unit, and a cleaning unit and an electrophotographic photosensitive member are integrally formed into a cartridge, and this cartridge is detachably mountable to an electrophotographic image forming apparatus main body. Or at least the developing means and the electrophotographic photosensitive member are integrally formed into a cartridge, and this cartridge is made detachable from the main body of the electrophotographic image forming apparatus.

[0004]

2. Description of the Related Art Conventionally, for example, in an electrophotographic image forming apparatus, an electrophotographic photosensitive member as an image carrier and a charging unit, a developing unit, and a cleaning unit as process units acting on the electrophotographic photosensitive member are provided. A structure in which a process cartridge is integrally formed and the process cartridge is detachably attached to the image forming apparatus main body is widely used.

In such an electrophotographic image forming apparatus of the process cartridge type, since the user has to replace the cartridge by himself / herself, a means for notifying the user when the developer is consumed, that is, a developer amount detecting device is used. Required.

Conventionally, as a developer amount detecting device, two electrodes are provided as a developer amount detecting means in a developer container integrally provided with a process cartridge, and a capacitance between the two electrodes is measured. There is a configuration that detects a change. That is, since the dielectric constant of the material constituting the toner generally used as the developer is different from the dielectric constant of air, the capacitance between the electrodes changes according to the amount of the toner distributed between the electrodes. This allows a voltage (eg, an AC voltage) between the electrodes
Is applied, the capacitance can be detected, and the capacitance can be sequentially converted to the amount of developer in the developer container by comparing with a predetermined level. Then, the result can be displayed on, for example, a display unit of the image forming apparatus, and the user can be sequentially notified of the developer amount.

[0007]

However, in the above-described conventional developer amount detecting device, there is a possibility that the developer amount cannot be accurately detected in the following cases. (1) When the position of the electrode is shifted from the predetermined position, the capacitance between the electrodes changes. (2) When the voltage value of the voltage (for example, AC voltage) applied to the electrode changes, the capacitance value is erroneously detected.

Further, there is provided a developer amount detecting device having a plurality of developer amount detecting means for detecting regions having different amounts of developer, and detecting the amount of developer in a wide area by selecting one of the detection results. In the image forming apparatus provided with the above, when the detection result of the developer amount is selected according to the detection result of any one of the developer amount detecting means, the detection accuracy is further deteriorated due to the problems (1) and (2). There was a risk of doing so.

Accordingly, it is an object of the present invention to provide an image forming apparatus, an electrophotographic image forming apparatus, and a process cartridge in which the detection accuracy of the developer amount is generally improved.

[0010] Another object of the present invention is to provide a method for detecting an amount of developer provided in a capacitance measuring type developer amount detecting means even when the position of an electrode and / or the voltage applied to the electrode deviates from a predetermined value. An object of the present invention is to provide an image forming apparatus, an electrophotographic image forming apparatus, and a process cartridge capable of detecting the amount of developer well.

Another object of the present invention is to provide a plurality of developer amount detecting means for detecting regions having different amounts of developer, and to detect the amount of developer in a wide region by selecting one of the detection results. In the configuration, even when the position of the electrode provided in the developer amount detection unit and / or the voltage applied to the electrode deviates from a predetermined value, the detection results of the plurality of developer amount detection units are accurately switched. It is an object of the present invention to provide an image forming apparatus, an electrophotographic image forming apparatus, and a process cartridge that can perform the above-described operations.

[0012]

The above object is achieved by an image forming apparatus, an electrophotographic image forming apparatus and a process cartridge according to the present invention. In summary, a first main aspect of the present invention is a developer accommodating section for accommodating a developer, a first developer amount detecting means including a plurality of electrodes arranged in the developer accommodating section, A first capacitance detecting means for detecting a capacitance between a plurality of electrodes of the first developer amount detecting means; and a detection result of the first capacitance detecting means being converted into a developer amount. A first developer amount conversion unit, and correcting the conversion result by the first developer amount conversion unit in accordance with a detection result of the first capacitance detection unit at a predetermined timing, An image forming apparatus is characterized in that a developer amount in the developer accommodating section is detected.

According to a second main aspect of the present invention, there is provided an electrophotographic image forming apparatus for detachably attaching a process cartridge and forming an image on a recording medium, comprising: (a) an electrophotographic photosensitive member; A developer accommodating section for accommodating a developer used for developing the electrostatic latent image formed on the body,
A first developer amount detection unit including: a developing unit for developing an electrostatic latent image formed on the electrophotographic photosensitive member; and an electrode member for measuring a capacitance between the developing unit and the developing unit. Mounting means for detachably mounting a process cartridge having means and storage means; and (b) the developing means of the first developer amount detecting means in a state where the process cartridge is mounted. First capacitance detection means for detecting capacitance between the electrode and
(C) comparing the detection result of the first capacitance detection means with a first correlation table representing a relationship between the capacitance value and the developer amount, thereby obtaining the first capacitance; And a first developer amount conversion means for converting a detection result of the detection means into a developer amount, wherein data corresponding to a detection result of the first capacitance detection means at a predetermined timing is stored in the process cartridge. A second correlation indicating a relationship between the data stored in the storage unit, the first correlation table, and a capacitance value different from the first correlation table and a developer amount; The correction width is determined in accordance with the table, and the correction width is added to the conversion result of the first developer amount conversion means, so that the conversion result by the first developer amount conversion means is converted to the predetermined value. Detection of the first capacitance detecting means at the timing. By correcting in accordance with the result,
An electrophotographic image forming apparatus is provided, wherein an amount of the developer in the developer accommodating section is detected.

According to a third main aspect of the present invention, in a process cartridge detachable from an electrophotographic image forming apparatus, (a) an electrophotographic photosensitive member, and (b) an electrostatic photosensitive member formed on the electrophotographic photosensitive member. A developer accommodating portion accommodating a developer used for developing the latent image; (c) a developing device for developing an electrostatic latent image formed on the electrophotographic photosensitive member; and a pair of the developing device. None, an electrode member for measuring a capacitance between the developing unit and the developing unit, a first developer amount detecting unit including: (d) a storage unit; and the storage unit, In the main body of the electrophotographic image forming apparatus, data corresponding to a result of detection of a capacitance between the developing means forming the first developer amount detecting means and the electrode member at a predetermined timing is stored. The process cartridge provided That.

[0015]

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

Embodiment 1 An embodiment of an image forming apparatus according to the present invention will be described with reference to FIG. FIG. 1 illustrates an image forming apparatus 1 according to the present embodiment.
00 shows a schematic configuration. The image forming apparatus 100 according to the present embodiment uses an electrophotographic recording material according to image information transmitted from an external device such as a personal computer communicably connected to the image forming apparatus main body 1. For example, a laser beam printer that forms an image on a recording sheet, an OHP sheet, or the like is used. Further, the image forming apparatus 100 of the present embodiment employs a process cartridge system in which an electrophotographic photosensitive member and process means acting on the electrophotographic photosensitive member are integrally formed as a cartridge and can be attached to and detached from the apparatus main body. are doing.

The image forming apparatus 100 has a cylindrical electrophotographic photosensitive member, that is, a photosensitive drum 21, which is driven to rotate in the direction of an arrow in FIG. The surface of the photosensitive drum 21 is uniformly charged by a charging roller 22 which is a roller-shaped charging means that rotates in contact with and rotates with the photosensitive drum 21. The charged surface of the photosensitive drum 21 is scanned and exposed by a laser beam radiated from a laser scanner unit 3 as an exposing means and according to image information. Thus, an electrostatic latent image of the target image information is formed on the photosensitive drum 21. This electrostatic latent image is then developed by the developing device 23.

That is, in this embodiment, the developing device 23 stores a magnetic one-component toner (toner) as a developer in a toner container (developer container) 23d made of a resin such as polystyrene as a developer accommodating portion. Accommodating. Developing device 23
A portion facing the photosensitive drum 21 is opened along the longitudinal direction of the photosensitive drum 21, and a developer carrier (developing roller) 23a, which is rotatable in a direction indicated by an arrow in FIG. Are arranged. The developing roller 23a
Fixed magnet roll 23b as a magnetic field generating means inside
have. In this embodiment, the toner container 23d is provided with three stirring members 23e, 23f, and 23g. Each stirring member has a rotating shaft 201 and a rotating shaft 2
It has a wing 202 fixed to 01, and rotates in the direction of the arrow in the figure to convey the toner in the toner container 23d toward the developing roller 23a while stirring. Then, the magnetic toner is supplied onto the developing roller 23a by the magnetic field of the magnet roll 23b.

Further, an elastic blade 23c as a developer layer thickness regulating member is in surface contact with the developing roller 23a with a predetermined pressing force, and the toner supplied to the developing roller 23a is With the rotation in the direction of the arrow, the elastic blade 23c and the developing roller 23a rub against each other to apply a triboelectric charge and regulate the thickness to a predetermined layer thickness. The toner on the developing roller 23a is
Is conveyed to a portion (developing portion) facing the photosensitive drum 21. Then, by applying a predetermined developing bias to the developing roller 23a, the developing roller 23a is transferred to the photosensitive drum 21 according to the electrostatic latent image formed on the photosensitive drum 21,
Visualize as a toner image. In this embodiment, a developing bias in which a DC voltage is superimposed on an AC voltage is applied to the developing roller 23a.

On the other hand, in the image forming apparatus 100, only one recording sheet S as a recording material set on the recording paper tray 4 which is a recording material accommodating section is sent out from the recording paper tray 4 by driving the pickup roller 5a. Then, the sheet is conveyed to the registration roller pair 5c by the sheet feeding roller pair 5b. Further, the recording paper P is conveyed to the transfer section where the photosensitive drum 21 and the transfer roller 6 as transfer means face each other at a predetermined timing by driving the registration roller pair 5c.

In the transfer section, the toner image on the photosensitive drum 21 is transferred to the recording paper S by applying a transfer electric field to the transfer roller 6. Further, the recording paper S on which the toner image has been transferred
Is sent to the fixing unit 7 by the conveying unit 8d. The fixing unit 7 fixes the unfixed toner image on the recording paper S by heat and pressure.

The recording paper S on which the image has been formed in this way is discharged by a discharge roller 8e or the like to a discharge tray 11 provided outside the apparatus main body 1.

The surface of the photosensitive drum 21 after the transfer of the toner image onto the recording paper S is cleaned by a cleaner 24. That is, the cleaner 24 is provided with the cleaning blade 2 as a cleaning unit that comes into contact with the photosensitive drum 21.
4a, the toner remaining on the photosensitive drum 21 is removed and collected in the cleaning container 24b.

FIG. 2 shows a schematic cross section of a process cartridge 2 which is detachable from the apparatus main body 1 in this embodiment.
That is, in the present embodiment, the process cartridge 2
A cleaning device including a drum-shaped electrophotographic photosensitive member (photosensitive drum) 21, a developing roller 23a as a developing unit opposed to the photosensitive drum 1, a toner container 23d connected to the developing roller 23a, and a cleaning unit 24a. The container 23b is integrally formed. The process cartridge 2 is removably mounted on the apparatus main body 1 via mounting means 9 provided on the apparatus main body 1.

According to this embodiment, the process cartridge 2 is provided with a memory unit as a storage means. As shown in FIG. 3, the memory unit 30 is mounted on the side surface of the process cartridge 2 in the present embodiment, although not limited thereto.

Next, the system configuration of the image forming apparatus of the present embodiment will be described with reference to the system block diagram of FIG.

Engine controller 50 as control means
Performs system control of the entire image forming apparatus 100. A central processing unit (CPU) (not shown) is provided inside the engine controller 50. Image forming apparatus 10
A series of system processing of 0 is performed according to a program stored in advance in the central processing unit. The high-voltage power supply 52 is a charging bias in which an AC voltage is superimposed on a DC voltage supplied to the charging unit 22, a developing bias in which an AC voltage is superimposed on a DC voltage supplied to the developing roller 23 a, and a DC voltage supplied to the transfer unit 6. A transfer bias and a fixing bias which is a DC voltage supplied to the fixing unit 7 are generated. Also, a driving unit 53 including a motor, a solenoid, and the like provided in the apparatus, a sensor group 8 provided at a predetermined position inside the apparatus, a display unit 10 for displaying a state of the apparatus, and a detection of a developer amount in the process cartridge 2 A capacitance detection device 61 for detecting capacitance based on the detection result of the member, and a memory control circuit 51 for controlling the memory unit 30 mounted on the process cartridge 2 are connected to the engine controller 50, respectively.

Here, the memory unit 30 will be described. The memory unit 30 has a built-in nonvolatile storage element, and can perform data writing and data reading by performing data communication with the image forming apparatus main body 1.

All data communication controls are performed by the memory control circuit 5
1 is performed. Data communication is performed in a non-contact manner by magnetic coupling between an antenna provided in the memory unit 30 and an antenna (not shown) provided in the image forming apparatus main body 1. When the process cartridge 2 is mounted on the main body 1 of the image forming apparatus, the antenna section of the memory unit 30 and the antenna provided on the main body 1 of the image forming apparatus come close to each other, so that communication becomes possible. A power supply circuit is provided inside the memory unit 30, and all the DC power used inside is supplied from this power supply circuit. In this power supply circuit, a DC voltage is generated by rectifying a current generated in an antenna by magnetic coupling of two antennas.

The memory unit 30 stores information on the process cartridge 2 and the like. In particular, in the present embodiment, the memory unit 30 stores a correction coefficient γ described later.

Next, a description will be given of a developer amount detecting device of the image forming apparatus 100 according to the present embodiment. The developer amount detection device provided in the image forming apparatus 100 according to the present embodiment can sequentially detect the amount of toner in the toner container 23d, which is a developer container. This is performed by detecting the capacitance between the developing roller 23a of the developing device 23 provided in the process cartridge 2 and the antenna electrode 41 which is a developer amount detecting member. The developing roller 23a functioning as an electrode and the antenna electrode 41 constitute a developer amount detecting unit.

The antenna electrode 41 can be formed of a metal such as SUS as a conductive member. In the present embodiment, the antenna electrode 41 is fixed in the entire longitudinal direction (the direction orthogonal to the conveying direction of the recording material S) along the bottom surface of the toner container 23d. In this embodiment, the antenna electrode 41 is disposed on the bottom surface of the position where the stirring member 23e closest to the developing roller 23a is provided among the three stirring members 23e, 23f, and 23g provided in the toner container 23d. You.

The toner is distributed between the antenna electrode 41 and the developing roller 23a. The dielectric constant of the material forming the toner is larger than that of air, and the capacitance between the developing roller 23a and the antenna electrode 41 changes according to the amount of the distributed toner. The detection of the capacitance is performed by the capacitance detection device 61 provided in the image forming apparatus main body 1.

FIG. 5 shows an internal circuit configuration of a capacitance detecting device 61 as a capacitance detecting means used in this embodiment.
In the present embodiment, the capacitance detecting device 61 detects the capacitance as a voltage value. The terminal 601 is connected to the antenna electrode 41 via an electric contact (not shown).
When the developing AC bias generated by the high-voltage power supply 52 is applied to the developing roller 23a, an AC current I1 flows to the terminal 601 due to the capacitance Cs between the antenna electrode 41 and the developing roller 23a. Here, the magnitude of the current I1 is
The value corresponds to the capacitance value Cs between the developing roller 23a and the antenna electrode 41. The current I1 is supplied to the diode 608 and the diode 606 provided at the input of the terminal 601.
Rectified by Then, the rectified current I2 is input to the integration circuit including the operational amplifier 611, the resistor 613, and the capacitor 614. Here, this current I
2 is a half-wave current of the current I2. On the other hand, the terminal 602
Is connected to a developing bias output section (not shown) inside the high voltage power supply 52. That is, the same developing AC bias as that of the developing roller 23a is applied to the terminal 602.

A capacitor 605 having a capacitance Ck is connected to an input portion of the terminal 602. When a developing AC bias is applied, an AC current I3 having a magnitude corresponding to the capacitance Ck flows. The capacitor 605 is a reference capacitor serving as a measurement reference, and the capacitance value Ck is set to a capacitance value between the antenna electrode 41 and the developing roller 23a when there is no toner in the toner container 23d. I have.
The current I3 is rectified by the diodes 609 and 607 set in the opposite direction to the input of the terminal 602, and the current I4 is input to the integration circuit. The current I4 is
The half-wave current has a polarity opposite to that of the current I2. The currents I2 and I4 input to the integration circuit are integrated, and a DC voltage Vdd corresponding to the average value of the total current of I2 and I4 is generated across the resistor 613. The frequency of the developing AC bias is fd,
Assuming that the amplitude is Vp and the resistance value of the resistor 613 is Rs2, V
dd can be represented by the following equation.

Vdd = K1 × Rs2 × fd × Vp × (Cs−Ck) (Equation 1) Here, K1 is a predetermined constant.

On the other hand, a predetermined reference voltage Vt2 is input to the positive input of the operational amplifier 611, and the operational amplifier 611
Has the following characteristics.

Vs2 = Vt2-K1 × Rs2 × fd × Vp × (Cs-Ck) (Equation 2)

As shown in the above equation 2, the operational amplifier 61
The output voltage Vs2 of 1 is a voltage value corresponding to the difference between the capacitance between the antenna electrode 41 and the developing roller 23a and the capacitance between the reference capacitor 605, that is, the amount of toner in the toner container 23d. The output Vs2 of the operational amplifier 611 is output from the output terminal 617 of the capacitance detecting device 61.

FIG. 6 shows the relationship between the remaining amount of toner in the toner container 23d and the output Vs2 of the capacitance detecting device 61. Here, the remaining amount of toner is a toner amount (%) in the toner container 23d when a predetermined amount of toner filled in the toner container 23d of the new process cartridge 2 is set to 100%. As shown in FIG. 6, in the configuration of the present embodiment, the output Vs2 of the capacitance detection device 61 does not change when the remaining amount of toner is 100% to 20%, but changes in the range of 20% to 0%. That is, the developer amount detection device of the present embodiment can detect an area where the amount of remaining toner is 20% to 0%.

Thus, detecting the developer amount sequentially is not limited to sequentially detecting the developer amount over the entire region from 100% to 0%. Here, the remaining amount of the developer of 0% does not only mean that the developer has completely disappeared. For example, when the remaining amount of the developer is 0%, even if the developer remains in the container,
This also includes the fact that the remaining amount of the developer is reduced to such an extent that a predetermined image quality (development quality) cannot be obtained.

In this embodiment, the capacitance detecting device 61
According to the circuit configuration of (1), when the toner amount decreases and the detected capacitance decreases, the output voltage value Vs2 increases. However, in the present invention, the increase / decrease relation of the data is changed to the relation of the present embodiment. It is not limited at all.

The terminal 617 is input to an analog / digital conversion terminal of the central processing unit in the engine controller 50. As a result, the voltage level Vs2 corresponding to the remaining toner amount is converted into digital data, and a calculation process of the toner amount value is performed.

Next, a process of converting the output level of the capacitance detecting device 61 converted into digital data into a toner amount will be described in detail. The conversion to the toner amount is performed using a conversion table stored in the central processing unit in the engine controller 50 in advance. In the present embodiment, the engine controller 50 has a function of a conversion unit that converts a detection result of the capacitance into a detected amount of the developer. Table 1
Exemplarily shows a part of the data configuration of the conversion table used in the present embodiment.

[0045]

[Table 1]

In this embodiment, the conversion table is DAT
The four data of A1, DATA2, DATA3, and DATA4 are configured as one set. DATA1 is data corresponding to the output Vs2 of the capacitance detecting device 61. On the other hand, DATA2 to DATA4 are data Tr indicating the remaining amount of toner corresponding to DATA1 in percentage.

Here, DATA2 is the antenna electrode 41
Is a predetermined center position, and is data representing characteristics when the voltage value of the developing AC bias is the predetermined center value. On the other hand, DATA3 and DATA4 are data representing characteristics when the position of the antenna electrode 41 and the voltage value of the developing AC bias deviate from a predetermined center value.

That is, in the present embodiment, as the conversion table, the correlation table (the first correlation table) between the capacitance and the developer amount when the position of the antenna electrode 41 and the voltage value of the developing AC bias are at the predetermined center value. : DATA1 vs. DATA
2) and a correlation table between the capacitance and the developer amount when the position of the antenna electrode 41 and the voltage value of the developing AC bias deviate from the predetermined center value (second correlation table: DATA)
1 to DATA3, DATA1 to DATA4)
The conversion from the capacitance to the remaining toner value is performed.

In this embodiment, DATA2, DATA3,
DATA4 shows the characteristics under the following conditions.

DATA2: The position of the antenna electrode 41 is at a predetermined center position, and the developing AC bias is 2000 Vpp. DATA3: The position of the antenna electrode 41 is 1 mm from the center position of DATA2 in the direction approaching the developing roller 23a.
Deviation position, development AC bias is 2100 Vpp DATA4: The position of antenna electrode 41 is 1 mm from the center position of DATA2 in the direction away from development roller 23a.
Deviation position, development AC bias is 1900 Vpp

For example, when Vs2 = 3.07V, D
ATA2 10.5%, DATA3 7.3%, DAT
A4 is 12.9%. FIG. 7 is a graph showing the conversion table used in the present embodiment. Table 1 shows a part of the conversion table by way of example. In the present embodiment, DATA1 is provided in the range of 0 V to 5 V as the conversion table. FIG. 7 shows DATA1 for DATA1.
2, the relationship between DATA3 and DATA4 is shown.

As can be seen from FIG. 7, the antenna electrode 41
The characteristics of the detection voltage and the remaining amount of toner change due to the deviation between the position and the voltage value of the developing AC bias.

Next, referring to the flowchart of FIG.
A series of conversion processes in the present embodiment will be described.

First, the detected capacitance value Vs2 is read (step 101), and the remaining toner data DATA2 corresponding to Vs2 is calculated using the conversion table (step 102).

Subsequently, the process proceeds to the process of correcting the detected value. This correction process corrects the deviation between the antenna position and the developing AC bias value with respect to the remaining toner data DATA2 when the installation position of the antenna electrode 41 and the developing AC bias are the center value. That is, DATA3 and DATA4 are read (step 103), and the correction coefficient γ stored in the memory unit 30 mounted on the process cartridge 2 is read (step 104).

Here, the correction coefficient γ is a value representing the amount of deviation of the antenna position and the developing AC bias value from the center value. The correction coefficient γ will be described with reference to FIG. FIG. 9 shows DA over the entire area where the remaining amount of toner is 100% to 0%.
9 shows characteristic curves of TA2, DATA3, and DATA4. In any of the characteristics, the characteristic curve is saturated in a region where the remaining amount of toner is around 20% to 100%, and the detection voltage Vs2 does not change with the change of the remaining amount of toner.

For each saturation voltage value, DAT
A2 is V01, DATA4 is a value higher by α than the saturation voltage V01 of DATA2, and DATA3 is D
It is a value lower by α than the saturation voltage value V01 of ATA2.

Therefore, in the present embodiment, the correction coefficient γ is determined in a region where the detection voltage value Vs2 is in a saturated state, that is, when the capacitance detecting device 61 detects a change in the amount of toner in the toner container 23d. It can be determined by the following calculation from the sample value Vs2 (0) in the developer amount region where the result does not change and the saturation voltage value of each data.

Γ = (Vs2 (0) −V01) ÷ α (Equation 3)

In the case of the image forming apparatus 100 of the present embodiment, the print amount executed by using the process cartridge 2 mounted on the apparatus main body 1 is stored in the memory unit 30 provided in the process cartridge 2. Therefore, in the present embodiment, the detection voltage value Vs2 is set as the predetermined timing for calculating the correction coefficient when the print amount reaches the predetermined value.
Is determined to be a saturation region. Then, in the present embodiment, the correction coefficient γ is calculated and determined based on the above equation 3 which is preset in the central processing unit in the engine controller 50. Further, the correction coefficient γ is stored in the memory unit 30.
Write to. As a result, when the remaining toner amount reaches the detection area, the correction coefficient γ stored in the memory unit 30 can be used thereafter.

At the above timing, the memory unit 3
As a data to be stored in 0, not a correction coefficient γ but data corresponding to a detection result of the capacitance detection device 61 at such timing is stored, and a correction coefficient is calculated when performing a correction operation described later. It can also be.

Referring to the flowchart of FIG. 8 again, a description will be given of the subsequent conversion processing procedure. After the correction coefficient γ is read in step 104, the corrected toner remaining amount Tr
2 ′ is calculated (step 105). In this embodiment, the corrected remaining toner amount Tr2 'is determined by the following calculation, depending on whether the value of the correction coefficient γ read in step 104 is positive or negative.

Tr2 ′ = DATA2− (DATA3−DATA2) × γ (when γ <0) (Equation 4-1) Tr2 ′ = DATA2 + (DATA4−DATA2) × γ (when γ> 0) .. (Equation 4-2)

The corrected toner amount T calculated by the above method
r2 ′ is the final toner remaining amount detection result. Then, a signal for displaying the detection result is transmitted to the apparatus main body 1.
Is transmitted to and displayed on the display unit 10 provided to the user (step 106).

A signal for displaying the detection result of the remaining amount of toner is transmitted to an external device (not shown) such as a personal computer communicably connected to the apparatus main body 1.
The user may be notified on a display unit such as a display panel provided in the external device.

As described above, in the developer amount detecting device of the image forming apparatus according to the present embodiment, the conversion table in the case where the antenna electrode position and the voltage value of the developing AC bias are the predetermined center values, the antenna electrode position and the The conversion from the capacitance to the remaining toner value is performed by using a conversion table when the voltage value of the developing AC bias deviates from the predetermined center value. Thereby, even when the antenna electrode position and the voltage value of the developing AC bias deviate from the predetermined center value, it is possible to accurately detect.

Embodiment 2 Next, another embodiment of the present invention will be described. The basic configuration of the image forming apparatus of this embodiment is the same as that of the first embodiment, and only the configuration of the developer amount detecting device is different. Therefore, components having the same functions and configurations as those of the image forming apparatus of the first embodiment are denoted by the same reference numerals, and detailed description thereof will be omitted.

In the first embodiment, the capacitance between a pair of electrodes, that is, the developing roller 23a constituting the first developer amount detecting means and the antenna electrode 41 is detected, and the remaining amount of toner is 2%.
The detection of the area of 0 to 0% was performed. On the other hand, in the developer amount detection device of the present embodiment, in addition to the antenna electrode 41 serving as the first developer amount detection member, the second developer amount detection device detects an area where the remaining amount of toner is 100 to 20%. As a means, a second developer amount detecting member 42 is provided, and a capacitance value based on a detection result of each developer amount detecting member is detected. As a result, the remaining amount is sequentially detected in the entire region from 100% to 0%.

FIG. 10 shows a schematic cross section of a process cartridge 2 ′ mounted in the image forming apparatus of this embodiment. FIG. 11 is a block diagram of a system configuration of the image forming apparatus according to the present embodiment. This embodiment is different from the first embodiment in that two capacitance detection devices, that is, a first capacitance detection device 61 and a second capacitance detection device 62 are provided.

As in the first embodiment, the first developer amount detecting means includes an antenna electrode 41 serving as a first developer amount detecting member.
And the developing roller 23a functioning as an electrode. The detection of the capacitance is performed by the first capacitance detection device 61. The method of detecting the capacitance by the first capacitance detecting device 61 and the method of converting the capacitance to the remaining amount of toner are the same as those described in the first embodiment with reference to FIG. The antenna electrode 41 has a toner remaining amount of 20.
The purpose is to detect an area around 0% to 0%. On the other hand, the second developer amount detecting member 42 has a toner remaining amount of 100% to 100%.
The purpose is to detect an area around 20%.

Next, the operation principle of the second developer amount detecting member 42 will be described. FIG. 13 shows the second developer amount detecting member 4.
2 is shown. FIG. 13A shows the second developer amount detecting member 4.
FIG. 13B shows a state in which the second line is expanded.
7 shows a state in which the developer amount detecting member 42 is disposed on the side surface of the toner container 23d.

As shown in FIG. 13, in the present embodiment,
The second developer amount detecting member 42 includes a measurement electrode 42A and a reference electrode 42B. First, the measurement electrode 42A will be described. The measurement electrode 42A has an input side and an output side which are formed on the same plane in parallel at a predetermined interval.
It has a pair of electrodes 42a and 42b. In this embodiment,
The electrode 42b is an output-side electrode, and the electrode 42a is an input-side electrode. Measuring electrode 42 provided with a pair of electrodes 42a, 42b
A is the toner container 2 such as the inner side surface of the toner container 23d.
It is arranged at a position where it touches the toner in 3d. Then, by measuring the capacitance between the paired electrodes 42a and 42b, a change in the area of the toner touching the surface of the second developer amount detecting member 42 is detected, and the toner container 23d is detected.
Can be known. That is, since the toner has a larger dielectric constant than air, if the area of the surface of the second developer amount detecting member 42 which is in contact with the toner changes, the capacitance between the paired electrodes 42a and 42b changes. I do.

Next, the reference electrode 42B of the second developer amount detecting member 42 will be described. In this embodiment, the input electrode of the reference electrode 42B is shared with the measurement electrode 42.
An output electrode 42c is formed on the same plane in parallel with the common input electrode 42a at a predetermined interval.

The reference electrode 42B is arranged in a position where it does not come into contact with the toner, although it is in the toner container 23d, and is designed such that the capacitance change when the environmental conditions are changed is the same as that of the measurement electrode 42A. Is done. In this embodiment, the electrode patterns of the measurement electrode 42A and the reference electrode 42B have the same shape. Therefore, by subtracting the value of the capacitance of the reference electrode 42B from the value of the capacitance of the measurement electrode 42A, it can be regarded that there is no change in the capacitance due to environmental conditions, and the detection accuracy can be improved. Becomes possible.

As shown in FIG. 13 (a), the second developer amount detecting member 42 is preferably provided on one surface of a single bendable substrate such as a flexible printed circuit board.
2A and a reference electrode 42B are provided, and are folded and disposed in the toner container 23d. The second developer amount detecting member 42 uses an adhesive such as a double-sided tape, and fixes the edge or the entire back surface so that the toner does not enter the back side of the measurement electrode A.

As shown in FIG. 10, in this embodiment, three stirring members 23e, 23f and 23g are provided in the toner container 23d.
Is provided. The second developer amount detecting member 42 is arranged around the second developer amount detecting member 42 with respect to the rotation shaft 201 of the stirring member 23f closest to the developing roller 23a.
Is disposed on the side wall on the drive side of the stirring member 23f in the toner container 23d. By arranging at this position, the area of the second developer amount detecting member 42 can be reduced while realizing the sequential detection, so that the component cost can be reduced. Further, the influence of the developing bias can be reduced by separating the developing roller from the developing roller 23a.

Since the second developer amount detecting member 42 has a very high sensitivity in the vicinity of the surface of the detecting member, it is effective to provide a surface wiping member to increase the detecting accuracy. At this time, it is preferable to provide a wiping member on the stirring member 23f for simplifying the configuration. In other words, as the wiping member, at the end of the stirring member 23f on the side where the second developer amount detecting member 42 is provided, the wing portion 202 which is usually a resin sheet member is long in the longitudinal direction, The second developer amount detection member 42 can be brought into contact with (penetrate into) the surface of the measurement electrode 42A. Alternatively, separately from the wing portion 202, a resin sheet member that penetrates into the surface of the measurement electrode 42 </ b> A of the second developer amount detection member 42 and wipes the shaft portion 201 is formed.
Can be fixed. At this time, the second developer amount detecting member 42 is arranged within a range in which the wiping member functions, corresponding to the toner stirring area of the stirring member 23f.

Next, the capacitance detecting means of the second developer amount detecting member 42 will be described in detail.

As shown in FIG. 11, the second developer amount detecting member 42 is connected to a second electrostatic capacitance detecting device 62 as a second electrostatic capacitance detecting means. The capacitance of the developer amount detecting member 42 is detected.

FIG. 12 is an internal circuit configuration diagram of the second capacitance detecting device 62. The terminal 716 is connected to the electrode 42a of the second developer amount detecting member via an electric contact (not shown), and outputs a detection clock CLK1. The clock CLK1 is generated by a resistor 717, a resistor 718, and a transistor 719. The signal CLKA is a clock output from the engine controller 50,
This is a rectangular wave having a frequency fc = 50 KHz and a duty = 50%. The clock CLKA has an amplitude = Vc and the terminal 7
16 and is input to the electrode 42 a of the second developer amount detecting member 42.

The terminal 701 is connected to the output electrode 42b on the measuring electrode 42A side of the second developer amount detecting member 42 via an electric contact (not shown). Common input electrode 42a
When the clock output from the terminal 716 is applied to
The alternating current I12 flows through the terminal 701 due to the capacitance Ct between the measurement side output electrode 42b and the common input electrode 42a. Here, the magnitude of the alternating current I12 depends on the capacitance value C
The value corresponds to t. The alternating current I12 is supplied to the diode 703 and the diode 7 provided at the input of the terminal 701.
04 is rectified. Then, the rectified current I1
3 is an operational amplifier 710, a resistor 712, and a capacitor 7
13 is input to the integrating circuit. Here, the current I13 is a one-way component current (half-wave current) of the current I12.
It is.

On the other hand, the terminal 702 is connected to an output electrode 42c on the reference electrode side of the second developer amount detecting member 42 via an electric contact (not shown). By the clock output from the terminal 716, a current I14 having a magnitude corresponding to the capacitance Cr between the reference side output electrode 42c and the common input electrode 42a flows through the terminal 702. The current I14 is supplied to the diode 7 set in the opposite direction to the input of the terminal 701.
08 and the diode 705 rectify the current I1
5 is input to the integration circuit. The current I14 is a half-wave current having a polarity opposite to that of the current I13. The currents I13 and I15 input to the integration circuit are integrated, and a DC voltage Vd1 corresponding to the average value of the sum of the currents I13 and I15 is generated across the resistor 712. The resistance value of the resistor 712 is Rs1
Then, the voltage Vd1 has a characteristic expressed by the following equation.

Vd1 = K5 × Rs1 × fc × Vc × (Ct−Cr) (Equation 5) Here, K5 is a predetermined constant.

On the other hand, a predetermined reference voltage Vt 1 is input to the positive input of the operational amplifier 710,
Has the following characteristics.

Vs1 = Vt1-K5 × Rs1 × fc × Vc × (Ct−Cr) (Equation 6)

As shown in the above equation 6, the operational amplifier 71
The output voltage Vs1 of 0 is applied to the electrode 42b on the measurement electrode 42A side.
And the capacitance between the common electrode 42a and the reference electrode 42
The voltage value corresponds to the difference between the capacitance between the B-side electrode 42c and the common input electrode 42a, that is, the voltage value according to the amount of toner in the process cartridge 2. Output Vs1 of operational amplifier 710
Is output from the output terminal 715.

The terminal 715 is connected to the engine controller 50
Connected to the analog-to-digital conversion terminal of the central processing unit. Voltage level Vs1 according to toner amount
Is converted into digital data and converted into a toner amount value.

The conversion processing to the toner amount value is performed using a conversion table stored in the central processing unit in the engine controller 50 in advance. Table 2 shows a part of the data structure of the conversion table used in the present embodiment.

[0089]

[Table 2]

The conversion table in this embodiment is DAT
The two data A5 and DATA6 are configured as one set. DATA5 is data corresponding to the output Vs1 of the second capacitance detecting device 62. On the other hand, DATA6
Is toner remaining amount data Tr1 representing the toner remaining amount corresponding to DATA5 in percentage.

For example, when Vs1 = 3.17V, the remaining toner amount Tr1 is converted to 73%, which is a detection result by the second developer amount detection member 42. Table 2 exemplarily shows a part of the conversion table. In the present embodiment, the conversion table is provided with DATA1 in the range of 0V to 5V.

Next, a detection result Vs2 by the first developer amount detecting member (antenna electrode) 41 detected in the same manner as in the method described in the first embodiment, and a detection result Vs2 by the second developer amount detecting member 42 From the two detection results of the detection result Tr1,
A method for determining the final detection result Tr3 of the remaining amount of toner will be described.

FIG. 14 is a flowchart showing a method of determining two detection results by the first and second developer amount detecting members 41 and 42.

First, the detection result Tr2 'of the remaining amount of toner by the first developer amount detecting member (antenna electrode) 41 is read (step 201). Here, the toner remaining amount Tr2 '
Is a value obtained by performing correction processing on the installation position of the antenna electrode 41 and the voltage value of the developing AC bias as described in the first embodiment.

Subsequently, it is determined whether or not the detection result Tr2 'of the remaining amount of toner by the antenna electrode 41 is equal to or less than 20% (step 202). Here, when it is determined that it is less than 20%, the detection result Tr2 ′ of the remaining amount of toner by the antenna electrode 41 is determined as the final remaining toner value Tr3 (step 203). Then, for example, a signal for displaying the remaining toner value Tr3 is transmitted and displayed on the display unit 10 provided in the apparatus main body 1, and is notified to the user (step 204).

On the other hand, if it is determined in step 202 that the detection value Tr2 'of the remaining amount of toner by the antenna electrode 41 is equal to or more than 20%, the toner by the second developer amount detection member (electrode member) 42 The remaining amount detection value Tr1 is read (step 205), and the detection result Tr1 of the remaining toner amount is determined as the final toner remaining amount value Tr3 (step 206). Then, as described above, the remaining amount of toner is displayed on the display unit 10 or the like to notify the user (step 2).
04).

As in the first embodiment, a signal for displaying the detection result of the remaining amount of toner is transmitted to an external device (not shown) such as a personal computer communicably connected to the apparatus main body 1. Alternatively, the user may be notified on a display unit such as a display panel provided in the external device.

As described above, in the developer remaining amount detecting device of the image forming apparatus according to the present embodiment, the conversion table when the position of the antenna electrode and the voltage value of the developing AC bias are the predetermined center value, Using the conversion table when the position and the voltage value of the development AC bias deviate from the predetermined center value, the conversion from the capacitance to the remaining toner value is performed,
Based on the result, it is determined whether to switch the detection result of the detection member that detects a different detection area. Thereby, even when the antenna electrode position and the voltage value of the developing AC bias deviate from the predetermined center value, it is possible to accurately switch the detection results of the plurality of detection members.

[0099]

As described above, according to the image forming apparatus, the electrophotographic image forming apparatus, and the process cartridge of the present invention, the position and / or the position of the electrode provided in the electrostatic capacity measuring type developer amount detecting means are provided. Even when the voltage value applied to the electrode deviates from a predetermined value, the amount of developer can be detected with high accuracy. Further, according to the present invention, in a configuration in which a plurality of developer amount detecting means for detecting regions of different developer amounts is provided, and a detection result of a wide region is selected by selecting one of the detection results, Even when the position of the electrode provided in the developer amount detecting means and / or the voltage applied to the electrode deviates from a predetermined value, the detection results of the plurality of developer amount detecting means can be accurately switched. . Therefore, according to the image forming apparatus, the electrophotographic image forming apparatus, and the process cartridge of the present invention, it is possible to improve the detection accuracy of the developer amount.

[Brief description of the drawings]

FIG. 1 is a schematic sectional view of an embodiment of an image forming apparatus according to the present invention.

FIG. 2 is a schematic sectional view of a process cartridge that can be attached to and detached from the image forming apparatus of FIG. 1;

FIG. 3 is a side view of the process cartridge for explaining an embodiment of a mounting portion of a memory unit of the process cartridge.

FIG. 4 is a system block diagram of an embodiment of an image forming apparatus according to the present invention.

FIG. 5 is an internal circuit diagram of the first capacitance detecting device according to the present invention.

FIG. 6 is a graph showing an example of an output characteristic of the first capacitance detection device.

FIG. 7 is a graph illustrating an example of output characteristics of the first capacitance detection device according to the position of an electrode member and an applied voltage.

FIG. 8 is a flowchart for explaining an embodiment of a developer amount conversion process according to the present invention.

FIG. 9 is a graph illustrating an example of an output characteristic of the first capacitance detection device for explaining a correction coefficient used for correcting the detection result of the developer amount according to the present invention.

FIG. 10 is a schematic cross-sectional view of another embodiment of the process cartridge detachable from the image forming apparatus according to the present invention.

FIG. 11 is a system block diagram of another embodiment of the image forming apparatus according to the present invention.

FIG. 12 is an internal circuit diagram of a second capacitance detection device according to the present invention.

FIG. 13A shows a configuration of a second developer amount detecting member.
It is a development view, (b) perspective view.

FIG. 14 is a flowchart for explaining another embodiment of the developer amount conversion processing according to the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Image forming apparatus main body 2 Process cartridge 10 Display unit 21 Photosensitive drum (image carrier, electrophotographic photosensitive member) 23 Developing device 23a Developing roller (developing unit) 23d Toner container (developer accommodating unit) 30 Memory unit (storage unit) Reference Signs List 50 engine controller 41 first developer amount detecting member 42 second developer amount detecting member 61 first capacitance detecting device (capacitance detecting means) 62 second capacitance detecting device (capacitance) Detection means)

Continued on front page F term (reference) 2H027 DD02 DE04 DE07 DE09 GB03 HB13 HB15 HB17 2H071 BA04 BA13 BA27 BA33 DA06 DA08 DA13 DA15 DA32 DA34 EA08 2H077 AA12 AB03 AC03 AD02 AD06 AD13 AD17 AD24 AD36 AE03 DA15 DA42 DA58 DA59 EA

Claims (25)

[Claims] A first developer amount detecting means including a developer accommodating portion for accommodating a developer, a plurality of electrodes disposed in the developer accommodating portion, and a first developer amount detecting device; First capacitance detecting means for detecting capacitance between a plurality of electrodes, and first developer amount converting means for converting the detection result of the first capacitance detecting means into a developer amount And correcting the conversion result by the first developer amount conversion means in accordance with the detection result of the first capacitance detection means at a predetermined timing, so that the developer in the developer accommodating section is corrected. An image forming apparatus for detecting an amount. 2. The method according to claim 1, wherein the predetermined timing is set in a developer amount region in which a detection result of the first capacitance detecting unit does not change with a change in a developer amount in the developer accommodating portion. 2. The image forming apparatus according to claim 1, wherein: 3. The first developer amount conversion unit converts a detection result of the first capacitance detection unit and a first correlation table representing a relationship between a capacitance value and a developer amount. 3. The image forming apparatus according to claim 1, wherein the amount of the developer is calculated by comparison. 4. The first correlation table, a second correlation table representing a relationship between a capacitance value and a developer amount different from the first correlation table, and the first correlation table at the predetermined timing. A correction width is determined in accordance with the detection result of the capacitance detecting means, and the correction width is added to the conversion result by the first developer amount converting means, thereby obtaining the conversion result by the developer amount converting means. 4. The image forming apparatus according to claim 1, wherein the correction is performed. 5. The correction width includes: (a) a relation between a capacitance value and a developer amount according to the detection result of the first capacitance detection means at the predetermined timing according to the first correlation table. The difference between the default value in the case and the actual detection result, and the default value when the relationship between the capacitance value and the developer amount follows the first correlation table, the capacitance value and the developer amount value (B) comparing the detection result of the first capacitance detecting means with the first correlation table, based on a difference from a predetermined value when the relation of the second correlation table follows the second correlation table. By multiplying the difference between the calculated amount of the developer and the amount of the developer calculated by comparing the detection result of the first capacitance detecting means with the second correlation table by the correction coefficient. The image forming apparatus according to claim 4, wherein the determination is made. 6. The first correlation table and the second correlation table, wherein the capacitance value and the developer when the relative positions of the plurality of electrodes of the first developer amount detecting unit are different from each other. The image forming apparatus according to claim 4, wherein the image forming apparatus represents a relationship with an amount. 7. The first capacitance detecting means detects a capacitance generated between the electrodes when a voltage is applied to at least one of the plurality of electrodes of the first developer amount detecting means. Wherein the first correlation table and the second correlation table have different voltage values of voltages applied to at least one of the plurality of electrodes of the first developer amount detecting means. 7. The image forming apparatus according to claim 4, wherein the relationship between the capacitance value and the developer amount is expressed. 8. The image forming apparatus according to claim 1, wherein at least the developer accommodating portion is a cartridge detachably mountable to an apparatus main body. 9. The cartridge according to claim 8, wherein the cartridge includes a storage unit, and the storage unit stores data corresponding to a detection result of the first capacitance detection unit at the predetermined timing. Image forming device. 10. The data according to the detection result of the first capacitance detecting means at the predetermined timing stored in the storage means of the cartridge, the first correlation table, and the first correlation table. And a second correlation table representing the relationship between the capacitance value and the developer amount, which is different from the first correction amount, and adds the correction width to the conversion result of the first developer amount conversion means. The image forming apparatus according to claim 9, wherein the conversion result is corrected by the first developer amount conversion unit. 11. The data stored in the storage means,
Regarding the detection result of the first capacitance detecting means at the predetermined timing, a difference between a default value and an actual detection result when the relationship between the capacitance value and the developer amount follows the first correlation table; And a default value when the relationship between the capacitance value and the developer amount follows the first correlation table, and a default value when the relationship between the capacitance value and the developer amount value follows the second correlation table. A correction coefficient obtained based on a difference between the correction amount and the value, and the correction width is a developer amount calculated by comparing a detection result of the first capacitance detection unit with the first correlation table; 2. The method according to claim 1, wherein a difference between a detection result of the first capacitance detecting unit and a developer amount calculated by comparing the detection result with the second correlation table is multiplied by the correction coefficient. 10 image forming apparatus. 12. The first correlation table and the second correlation table, wherein the capacitance value and the developer when the relative positions of the plurality of electrodes of the first developer amount detecting means are different from each other. 11. The method according to claim 10, wherein the relationship with the quantity is represented.
Or 11 of the image forming apparatus. 13. The first capacitance detecting means detects a capacitance generated between the electrodes when a voltage is applied to at least one of the plurality of electrodes of the first developer amount detecting means. Wherein the first correlation table and the second correlation table
The correlation table indicates that the relationship between the capacitance value and the developer amount when the voltage value of the voltage applied to at least one of the plurality of electrodes of the first developer amount detection unit is different. The image forming apparatus according to claim 10, 11 or 12, wherein: 14. The image forming apparatus according to claim 1, wherein one of the plurality of electrodes of the first developer amount detecting means is a developing means for supplying a developer to the image carrier. An image forming apparatus according to any of the above items. 15. The first capacitance detecting means detects a capacitance generated between the developing means and an electrode forming a pair with the developing means when an AC voltage is applied to the developing means. The image forming apparatus according to claim 14, wherein: 16. A second developer amount detecting means provided in the developer accommodating portion for detecting a developer amount in an area different from the first developer amount detecting means; And a second developer amount conversion means for converting a detection result of the second developer amount detection means into a developer amount, based on a value obtained by correcting the conversion result of the first developer amount conversion means. ,
4. The method according to claim 1, wherein a conversion result by said first developer amount conversion means or a conversion result by said second developer amount conversion means is selected to detect a developer amount in said developer container. Item 15. The image forming apparatus according to any one of Items 15. 17. The second developer amount detecting means includes a plurality of electrodes, and a second capacitance for detecting a capacitance between the plurality of electrodes of the second developer amount detecting means. 17. The image forming apparatus according to claim 16, wherein a detection result of the detection unit is converted into a developer amount by the second developer amount conversion unit. 18. The first developer amount detecting means for measuring a capacitance between the developing means for supplying a developer to the image carrier as the plurality of electrodes and the developing means. The second developer amount detecting means has a pair of input and output electrodes formed on the same plane in parallel at a predetermined interval, and a capacitance between the electrodes. 18. The image forming apparatus according to claim 17, wherein the image forming apparatus comprises: an electrode member for measuring the measurement value; 19. The apparatus according to claim 16, wherein said first developer amount detecting means has sensitivity to a developer in a developer amount region smaller than said second developer amount detecting means.
17 or 18. 20. An electrophotographic image forming apparatus which detachably attaches a process cartridge and forms an image on a recording medium, comprising: (a) an electrophotographic photosensitive member; and an electrostatic latent image formed on the electrophotographic photosensitive member. A developer accommodating portion for accommodating a developer used for developing, a developing unit for developing an electrostatic latent image formed on the electrophotographic photoreceptor, and a capacitance between the developing unit Mounting means for removably mounting a process cartridge having first developer amount detecting means comprising: an electrode member for measurement; and storage means; and (b) mounting the process cartridge. A first electrostatic capacity detecting means for detecting an electrostatic capacity between the developing means and the electrode of the first developer amount detecting means in the state; and (c) a first electrostatic capacity detecting means. The detection result of the capacity detection means And a first correlation table representing a relationship between the capacitance value and the developer amount, thereby converting the detection result of the first capacitance detecting means into a developer amount. Means for converting the amount of medicine, wherein data corresponding to the detection result of the first capacitance detecting means at a predetermined timing is stored in the storage means of the process cartridge, and the data stored in the storage means; The first correlation table and a second correlation table different from those of the first correlation table, each representing a relationship between a capacitance value and a developer amount.
The correction width is determined according to the correlation table
By adding the correction width to the conversion result of the developer amount conversion unit, the conversion result by the first developer amount conversion unit is added to the detection result of the first capacitance detection unit at the predetermined timing. An electrophotographic image forming apparatus, wherein the amount of the developer in the developer accommodating portion is detected by correcting the amount of the developer. 21. An electrode member for measuring a capacitance between electrodes, wherein the process cartridge further has a pair of input and output electrodes formed on the same plane in parallel at a predetermined interval. And a second developer amount detecting means having a measurement side electrode in contact with the developer and a reference electrode not in contact with the developer, and the apparatus main body further includes a state in which the process cartridge is mounted, A second capacitance detecting means for detecting a capacitance between a pair of electrodes of the second developer amount detecting means; and a detection result of the second capacitance detecting means as a developer amount. And a second developer amount conversion unit that converts the conversion result of the first developer amount conversion unit based on the corrected value of the conversion result of the first developer amount conversion unit. Selecting the conversion result of the second developer amount conversion means, 21. The electrophotographic image forming apparatus according to claim 20, wherein the amount of the developer in the developer container is detected. 22. The electronic device according to claim 20, wherein the process cartridge further includes at least one of a charging unit for charging the electrophotographic photosensitive member and a cleaning unit for cleaning the electrophotographic photosensitive member. Photographic image forming device. 23. A process cartridge detachable from an electrophotographic image forming apparatus, wherein: (a) an electrophotographic photosensitive member; and (b) a developing device for developing an electrostatic latent image formed on the electrophotographic photosensitive member. A developer accommodating section for accommodating an agent, (c) developing means for developing an electrostatic latent image formed on the electrophotographic photosensitive member, and a pair with the developing means,
A first developer amount detecting unit including an electrode member for measuring a capacitance between the developing unit and the developing unit; and (d) a storing unit, wherein the storing unit includes the electronic device. In the main body of the photographic image forming apparatus, at a predetermined timing, data corresponding to a result of detecting a capacitance between the developing means forming the first developer amount detecting means and the electrode member is stored. And process cartridge. 24. An electrode member having a pair of electrodes on an input side and an output side which are formed on a same plane in parallel at a predetermined interval and for measuring a capacitance between the electrodes. 24. The process cartridge according to claim 23, further comprising a second developer amount detecting means having a measurement side electrode in contact with the developer and a reference electrode not in contact with the developer. 25. The process cartridge according to claim 23, further comprising at least one of charging means for charging said electrophotographic photosensitive member and cleaning means for cleaning said electrophotographic photosensitive member.