JP2001228698A - Developer residual amount detecting device, developing device, cartridge and electrophotographic image forming device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To successively and accurately detect toner residual amount from a state where toner is full until a state where it is used up. SOLUTION: By providing two devices, that is, an optical system developer residual amount detecting device detecting the toner residual amount inside a developer container 17 by transmitting light through the container 17 and receiving the light transmitted through the container 17, and an antenna system developer residual amount detecting device detecting the toner residual amount inside the container 17 by providing an antenna electrode 13 near the container 17 and detecting the electrostatic capacity of the toner existing between a developing roller 3 and the electrode 13, the toner residual amount is detected by using the antenna system developer residual amount detecting device while the toner residual amount is 100% to 50% and using the optical system developer residual amount detecting device when the toner residual amount is <=50%.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention generally relates to an electrophotographic system in which an electrostatic latent image is formed on an image carrier by an electrophotographic method, and the electrostatic latent image is visualized by a developer contained in a developing device. Regarding the photographic image forming apparatus, in particular, a developer remaining amount detecting device for sequentially detecting the remaining amount of the developer contained in the developer container, an electrophotographic image forming apparatus having the developer remaining amount detecting device, The present invention relates to a cartridge and a developing device.

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

[0003] The cartridge includes a process cartridge and a developing cartridge. The process cartridge is formed by integrally forming at least one of a charging unit, a developing unit and a cleaning unit and an electrophotographic photosensitive member. Is removable from the electrophotographic image forming apparatus body, or
At least the developing means and the electrophotographic photosensitive member are integrally formed into a cartridge, and this cartridge is detachable from the main body of the electrophotographic image forming apparatus. Further, the developing cartridge means a cartridge in which at least the developing means and the developer container are integrally formed as a cartridge, and which is detachably mountable to the main body of the electrophotographic image forming apparatus.

[0004]

2. Description of the Related Art In electrophotographic image forming apparatuses such as copiers and laser printers, various kinds of developer remaining amount detecting devices have been proposed. The developer remaining amount detecting device is a device that presents information to the user that the developer (toner) in the cartridge has been consumed and it is time to replace the developer, for example.
This is one of the important usability functions. The user can recognize from the developer remaining amount detecting device that the cartridge is about to be replaced. As a result, it is possible to purchase and prepare a new cartridge in advance before the toner is exhausted, and it is easy to determine that the image disturbance due to the low remaining amount of toner is not a failure of the electrophotographic image forming apparatus. It becomes possible.

As an example of the developer remaining amount detecting device, a method of detecting the amount of light passing through the cartridge using an optical semiconductor element, an antenna electrode provided opposite to a developing roller as a developer carrying member, There has been proposed a method of detecting the electrostatic capacity of toner formed between the developing roller and the antenna electrode by applying an AC bias to the developing roller.

A developer remaining amount detecting device using an optical semiconductor element is provided with two transparent windows so that light passes through the cartridge when the remaining amount of toner becomes small. A light emitting element and a light receiving element are respectively arranged near each transparent window. When the toner is filled, the light emitted from the light emitting element cannot pass through the cartridge because it is blocked by the toner. When the remaining amount of toner becomes small, light emitted from the light emitting element can gradually pass through the cartridge, and the remaining amount of toner can be detected according to the amount of transmitted light (transmission time).

On the other hand, as described above, the developer remaining amount detecting device using an antenna electrode is provided with an antenna electrode opposed to the developing roller, and by applying an AC bias to the developing roller, the developing roller is connected to the electrode. The capacitance of the toner formed therebetween is detected. That is, since the change in the capacitance of the toner is detected, it is possible to sequentially detect the transition from when the cartridge is fully filled with the toner to when the remaining amount of the toner becomes zero.

[0008]

However, an apparatus for detecting the remaining amount of developer using an optical semiconductor element requires an optical path through which light passes without toner to detect the remaining amount of toner. . That is, it is difficult to detect a change in the remaining amount of toner until the remaining amount of toner is low, and it is possible to sequentially detect a change in the remaining amount of toner from the time when the toner is fully charged to the time when the toner is empty. There was a problem that it was difficult.

Further, since the developer remaining amount detecting device using the antenna electrode detects the capacitance of the toner, the capacitance becomes extremely small when the amount of the remaining toner becomes small. . Therefore, when the amount of remaining toner is small, it is difficult to detect the change in capacitance.
In addition, since an unstable element such as a small capacitance is detected, there is a problem that the variation in detection is large and the accuracy is poor when a small amount of toner is important for usability.

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a developer remaining amount detecting device capable of sequentially and accurately detecting the remaining amount of a developer from the full amount to the empty amount. An object of the present invention is to provide a developing device, a cartridge, and an electrophotographic image forming apparatus provided with an amount detecting device.

[0011]

The above object is achieved by a developer remaining amount detecting device, a developing device, a cartridge, and an electrophotographic image forming apparatus according to the present invention. In summary, the present invention provides a developer carrier for housing a developer for developing an electrostatic latent image formed on an electrophotographic photosensitive member, and transporting the developer to the electrophotographic photosensitive member. In an electrophotographic image forming apparatus provided with a developing device having a developer container provided, light is incident on the developer container in a developer remaining amount detecting device for detecting a developer remaining amount in the developer container. A first detecting unit for detecting a remaining amount of the developer in the developer container by receiving light transmitted through the developer container, and an electrode in the developer container or in the vicinity of the developer container. And a second detecting means for detecting a remaining amount of the developer in the developer container by detecting a capacitance of a developer existing between the developer carrying member and the electrode. The first detecting means or the second detecting means in accordance with the remaining amount of the developer. A developer remaining amount detecting apparatus characterized by selectively using the detection means.

According to a second aspect of the present invention, the developer is mounted on the main body of the electrophotographic image forming apparatus and contains a developer for developing an electrostatic latent image formed on the electrophotographic photosensitive member. A developer container having a developer carrier for conveying the electrophotographic photoreceptor, and a developer remaining amount detecting device for detecting a remaining amount of the developer in the developer container, A first detection unit configured to detect a remaining amount of the developer in the developer container by irradiating the developer container with light and receiving light transmitted through the developer container; Means, an electrode is provided in the developer container, or in the vicinity of the developer, and by detecting the electrostatic capacity of the developer existing between the developer carrier and the electrode, the inside of the developer container is detected. Developing means for detecting the remaining amount of the developer. It said first detection means in accordance with the remaining amount,
Alternatively, a developing device is provided, wherein the second detecting means is selectively used.

According to a third aspect of the present invention, there is provided a cartridge detachably mountable to an electrophotographic image forming apparatus main body.
(A) an electrophotographic photosensitive member; and (b) a developer for developing an electrostatic latent image formed on the electrophotographic photosensitive member.
A developing device having a developer container provided with a developer carrier for transporting the developer to the electrophotographic photosensitive member;
(C) a developer remaining amount detecting device for detecting a remaining amount of the developer in the developer container, wherein the developer remaining amount detecting device emits light to the developer container, A first detection unit that detects the remaining amount of the developer in the developer container by receiving light transmitted through the developer container, and an electrode provided in the developer container or in the vicinity of the developer container. And a second detection unit for detecting a remaining amount of the developer in the developer container by detecting a capacitance of a developer existing between the developer carrier and the electrode. A cartridge is provided, wherein the first detection means or the second detection means is selectively used in accordance with the remaining amount of the medicine.

According to a fourth aspect of the present invention, in a cartridge detachable from an electrophotographic image forming apparatus main body,
(A) a developer container containing a developer for developing an electrostatic latent image formed on an electrophotographic photosensitive member and a developer carrier for transporting the developer to the electrophotographic photosensitive member; And (b) a developer remaining amount detecting device for detecting the remaining amount of the developer in the developer container, wherein the developer remaining amount detecting device is provided in the developer container. First detection means for detecting the remaining amount of the developer in the developer container by receiving light transmitted through the developer container and receiving light, and the developer container or the developer container A second detecting means for providing an electrode in the vicinity and detecting a remaining amount of the developer in the developer container by detecting a capacitance of a developer existing between the developer carrier and the electrode; ,
, And wherein the first detection means or the second detection means is selectively used in accordance with the remaining amount of the developer.

According to a fifth aspect of the present invention, there is provided an electrophotographic image forming apparatus for forming an image on a recording medium, comprising: (a) an electrophotographic photosensitive member; Electrostatic latent image forming means for forming a latent image,
(C) a developer containing a developer for developing an electrostatic latent image formed on the electrophotographic photosensitive member, and a developer including a developer carrier for transporting the developer to the electrophotographic photosensitive member A developing device having a container, and (d) a developer remaining amount detecting device for detecting a remaining amount of the developer in the developer container, wherein the developer remaining amount detecting device is provided with the developer container. And detecting the remaining amount of the developer in the developer container by receiving light transmitted through the developer container.
By providing an electrode in the developer container or in the vicinity of the developer container, and detecting the electrostatic capacity of the developer existing between the developer carrier and the electrode by detecting the electrostatic capacity of the developer. And a second detecting means for detecting the remaining amount of the developer in the container, wherein the first detecting means according to the remaining amount of the developer,
Alternatively, there is provided an electrophotographic image forming apparatus characterized by selectively using the second detecting means.

According to a sixth aspect of the present invention, there is provided an electrophotographic image forming apparatus for detachably mounting a cartridge and forming an image on a recording medium, comprising: (a) an electrophotographic photosensitive member; A developing device for storing a developer for developing the electrostatic latent image formed on the photoconductor, and a developer container having a developer carrier for transporting the developer to the electrophotographic photoconductor; And (b) a developer remaining amount detecting device for detecting a remaining amount of the developer in the developer container. An amount detection device configured to detect light remaining on the developer container by irradiating the developer container with light and receiving light transmitted through the developer container; and In the developer container or near the developer container A second detecting means for detecting the remaining amount of the developer in the developer container by detecting the electrostatic capacity of the developer existing between the developer carrying member and the electrode, Wherein the first detection means or the second detection means is selectively used according to the remaining amount of the developer.

According to a seventh aspect of the present invention, there is provided an electrophotographic image forming apparatus for forming an image on a recording medium in which a cartridge is detachable, wherein (a) the electrophotographic photosensitive member is formed on the electrophotographic photosensitive member. A cartridge having a developing device that contains a developer for developing an electrostatic latent image and has a developer container having a developer carrier for transporting the developer to the electrophotographic photosensitive member is detachable. Mounting means for mounting, and (b) a developer remaining amount detecting device for detecting a remaining amount of the developer in the developer container, wherein the developing agent remaining amount detecting device comprises: Light enters the container,
First detection means for detecting the amount of the developer remaining in the developer container by receiving light transmitted through the developer container, and an electrode provided in the developer container or in the vicinity of the developer container And a second detection unit that detects a remaining amount of the developer in the developer container by detecting a capacitance of a developer existing between the developer carrier and the electrode, An electrophotographic image forming apparatus is provided, wherein either the first detecting means or the second detecting means is selectively used according to a remaining amount of a developer.

In each of the above-mentioned inventions, according to one embodiment, when the remaining amount of the developer is at most half or less of the full amount, the first detecting means is used.

According to another embodiment, when the remaining amount of the developer is at least one fifth or less of the full amount, the second detecting means is used.

According to still another embodiment, the electrophotographic image forming apparatus has a plurality of the developing devices, and the number of the electrodes is at most less than the number of the developing devices.

According to another embodiment, the electrophotographic image forming apparatus has a plurality of the cartridges, and the number of the electrodes is at most less than the number of the cartridges.

[0022]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a developer remaining amount detecting device, a developing device, a cartridge, and an electrophotographic image forming apparatus according to the present invention will be described in more detail with reference to the drawings.

Embodiment 1 FIG. 1 shows a first embodiment of the present invention.
This will be described with reference to FIG.

First, the schematic operation of the color laser printer which is the electrophotographic image forming apparatus of this embodiment will be described with reference to FIG. The printer of this embodiment employs a rotary rotation system in which four developing cartridges can be interchanged.

A high voltage bias is applied to a charging roller 2 serving as a charging unit, and a photosensitive drum 1 serving as an electrophotographic photosensitive member is applied.
4 is charged to a uniform potential. The surface of the photoreceptor drum 14 charged to a uniform potential is laser-exposed by the laser unit 1 serving as an electrostatic latent image forming unit to form an electrostatic latent image. The latent image formed on the photosensitive drum 14 is
The developer is developed via the developing roller 3 by the developer (toner) supplied from the developer container 17 of the developing cartridge 11a. The toner image developed on the photosensitive drum 14 is
The image is transferred onto the intermediate transfer belt 4 by the primary transfer roller 5 to which the primary transfer bias is applied. The process of charging, exposure, development, and primary transfer is performed in each developing cartridge 11a.
The processing is sequentially performed on 11b, 11c, and 11d. The toner images of the respective colors superimposed and transferred on the intermediate transfer belt 4 are conveyed to a position in contact with the secondary transfer roller 6 and are collectively transferred onto the transfer material P again. Transfer material P on which toner image has been transferred
Is conveyed to the fixing device 12, is heated and fixed, and is discharged out of the apparatus.

FIG. 2 shows a color laser printer according to this embodiment.
As shown in FIG. 1, the yellow, magenta, cyan, and black developing cartridges 11a to 11d can be loaded into the developing rotary 11 via the mounting means 15 (see FIG. 1). Light guides 7 and 10 made of a transparent resin are provided in the loading portions of the respective developing cartridges 11 a to 11 d of the developing rotary 11.
1a to 11d are arranged respectively. Further, a stirring rod 16 for stirring the toner is provided inside each of the developing cartridges 11a to 11d, and is rotatably driven during a developing process.

Next, the developer remaining amount detecting device of the present embodiment will be described with reference to FIG. FIG. 1 shows only the developing cartridge 11a for convenience.

The developer remaining amount detecting device of this embodiment uses both an optical developer remaining amount detecting device (first detecting means) and an antenna type developer remaining amount detecting device (second detecting means). By doing so, the remaining amount of toner can be sequentially detected from the time when the toner in the developing cartridge is full to the time when it is empty.

The optical type developer remaining amount detection device detects the amount of transmitted light (transmission time) by passing light through the developing cartridge 11a, and measures the amount of remaining toner. The antenna type developer remaining amount detecting device is provided with an antenna electrode 13 opposed to the developing roller 3 so that the developing roller 3
Is applied with an AC developing bias, the electrostatic capacity of the toner formed between the developing roller 3 and the antenna electrode 13 is detected to measure the remaining amount of toner.

First, an optical type developer remaining amount detecting device will be described in detail. As shown in FIGS. 1 and 2, transparent windows 8 and 9 are provided on the outer surface of the developing cartridge 11a for detecting the amount of remaining toner in an optical system, respectively. The remaining amount of toner is detected by monitoring the transmission amount (transmission time).

The light guide 7 includes a developing cartridge 11
2 is located at a position where it is in contact with the photosensitive drum 14, that is, at the position of the developing cartridge 11a in FIG.
The light emitted by 22a (disposed in the front direction in FIG. 2) is guided to the transparent window 8 in the developing cartridge 11a. The light guide 10 is provided between the transparent window 8 and the developing cartridge 11.
2A, the transmitted light passing through the transparent window 9 is again transmitted to the optical sensor 22b (FIG.
In front of the camera).

FIG. 3 shows the relationship between the detected transmitted light and time. When the amount of remaining toner is large, the light from the LED 22a does not pass through the inside of the developing cartridge 11a and is blocked by the toner even if the toner is stirred by the stirring rod 16, and as a result, does not reach the optical sensor 22b. However, when the amount of remaining toner becomes small, the stirring of the stirring rod 16 causes
The light from a gradually passes through the inside of the developing cartridge 11a, and as a result, reaches the optical sensor 22b. By monitoring the transmission amount (transmission time) of the light passing through the developing cartridge 11a, the remaining amount of toner is measured. The light transmission amount (transmission time) is determined based on the time when the pulse-like detection signal SNSA falls below the light presence / absence threshold. In FIG. 3, the light transmission time is A <B <(C +
In the order of D), the toner amount increases, and accordingly, the remaining toner amount decreases in that order.

More specifically, the detection signal SNSA
Is A of the CPU 25a in the controller 25 shown in FIG.
After being transmitted to the / D port, the CPU 25a measures a time period during which the received detection signal is equal to or less than a predetermined light presence / absence threshold value, and stores the data in the RAM 25b.
Then, the remaining toner amount is calculated from a table stored in the ROM 25c in advance.

FIG. 4B shows the relationship between the light transmission time and the remaining amount of toner. When the remaining amount of toner is equal to or more than 50%, it is difficult to transmit light, so that a change in the remaining amount of toner cannot be detected. On the other hand, when the remaining amount of toner is 25% or less,
A change in the remaining amount can be detected accurately. If the light transmission time is within the range of Ta, Tb, and Tc, the remaining toner amounts are 25%, 15%, and 0%, respectively. The other developing cartridges 11b to 11d are arranged at the same position by the rotation of the developing rotary 11, and the remaining toner amount is similarly measured in the same manner.

Next, an antenna type developer remaining amount detecting device will be described in detail. As shown in FIG. 2, in this embodiment, since the four developing cartridges 11a to 11d are provided in the developing rotary 11, the antenna electrodes 13 are provided.
Is disposed at the central portion of the developing rotary opposite to the developing roller 3 and is commonly used for the respective color developing cartridges 11a to 11d. The developer containers 17 of the developing cartridges 11 a to 11 d are arranged between the developing roller 3 and the antenna electrode 13, and apply an AC bias to the developing roller 3 so that toner formed between the developing roller 3 and the electrode 13 is removed. The capacitance is detected from the antenna electrode 13. Note that the antenna electrode 13 can be arranged at an appropriate position in the developer container 17.

FIG. 1 is a schematic block diagram thereof. The antenna type toner remaining amount detecting circuit 20 includes a developing rotary 24
, A high-voltage power supply 21 for supplying a developing bias, and a controller 25, and capacitors C1 and C3, a high-voltage capacitor Cr, a diode D1,
D2, D3, and D4, and resistors R1 and R3.

The AC current flowing through the electrostatic capacitance of the toner detected from the antenna electrode 13 and the AC current flowing from the high voltage power supply 21 to the high voltage capacitor Cr are rectified and converted, and the difference voltage is used as a toner remaining amount detection signal SNSB. , To the controller 25. However, between the developing roller 3 and the antenna electrode 13, the toner capacitance Ct
s and a distribution capacitance Ctr due to members other than the toner. Therefore, the antenna electrode 13 detects the current flowing through the distributed capacitance Ctr even when the remaining amount of toner becomes zero. That is, when the remaining amount of toner is 0%, the detection value does not become zero.

FIG. 4A shows the relationship between the detected value of the capacitance between the developing roller and the antenna electrode and the remaining amount of toner. If the detected value is within each range of Va, Vb, Vc, Vd, and Ve,
The remaining toner amounts are 100%, 75%, 50%, and 25%, respectively.
%, 0%. Each detection value Va in each toner remaining amount state,
Since Vb, Vc, Vd, and Ve vary, it is difficult to accurately detect the remaining amount of toner.
It is detected linearly from the% state to the 0% state.

As described above, the optical type toner remaining amount detection circuit 22 in this embodiment detects an accurate remaining amount of toner when the remaining amount of toner is small. The remaining amount of toner is linearly detected throughout the period from when the amount of toner is large to when the amount is small.

The CPU 25a in the controller 25 has two pieces of information of the toner remaining amount signal SNSA detected by the optical type developer remaining amount detecting device and the toner remaining amount signal SNSB detected by the antenna type developer remaining amount detecting device. By
The remaining toner amount to be displayed on the toner remaining amount display 23 as the developer remaining amount display means is determined.

The display of the remaining amount of toner includes "no toner", "notification of toner absence" of 0% to 15% of remaining toner, "15% to 25%" of remaining toner, and "25% to 50" of remaining toner.
% ", The remaining toner amount" 50% to 75% ", and the remaining toner amount" 75% to 100% ".

The CPU 25a controls each developing cartridge 11
When a to 11d are set at predetermined positions where development is performed, the light transmission amount (transmission time) of the light emitted by the optical type toner remaining amount detection circuit 22 is measured, and the conversion table stored in the ROM 25c is stored. Calculates the toner remaining amount data corresponding to the light transmission amount (transmission time).
5b.

Next, at the timing when the developing bias is applied to the developing roller 3, the remaining amount of toner is detected by the antenna system. In the detection of the remaining amount of toner by the antenna method, a plurality of samplings are performed in one detection sequence to detect a voltage. The data is temporarily stored in the RAM 25b.
To memorize. Thereafter, an averaging process of the stored plurality of detected voltage values is performed, and the averaged detected voltage value is stored in the ROM 2.
Based on the table stored in 5c, the remaining toner data corresponding to the voltage value is calculated and stored in the RAM 25b.

The CPU 25a determines that the remaining amount of toner is 100% or less.
During the period of 50%, a signal is transmitted to be displayed on the toner remaining amount display 23 according to the antenna type developer remaining amount detecting device. That is, when the detected value in FIG. 4A is Va, a signal is transmitted to the remaining toner indicator 23 so as to display the remaining toner as “75% to 100%”. Until the remaining toner amount of 75% is detected, the remaining toner amount is “7”
5% to 100%. " When the toner remaining amount 75% is detected, a signal is transmitted to the toner remaining amount indicator 23 so as to display the toner remaining amount “50% to 75%”. Until the remaining toner amount of 50% is detected, the remaining toner amount is “50% to 7%”.
5% ". When the remaining toner amount of 50% is detected, the remaining toner amount “25% to 50%” is displayed.
A signal is transmitted to the remaining toner indicator 23. Thereafter, the remaining toner amount “25% to 50%” is kept displayed until the optical toner remaining amount detection circuit 22 detects the remaining toner amount of 25%.

When the toner remaining amount detection circuit 22 of the optical system detects that the remaining amount of toner is 25% or less, a signal is sent to the remaining toner amount indicator 23 so as to display the remaining amount of toner "15% to 25%". Send. After that, the remaining amount of toner “15% to 25%” is kept displayed until the remaining amount of toner 15% is detected in accordance with the toner remaining amount detection circuit 22 of the optical system. When the remaining toner amount of 15% is detected, a signal is transmitted to the toner remaining amount display 23 so as to display "notification of no toner". Until the remaining toner amount of 0% is detected, the display of "notification of no toner" is continuously displayed. When 0% of the remaining toner is detected,
In order to display "no toner", the toner remaining amount indicator 2
3 to send a signal.

As described above, according to the present embodiment, an optical toner remaining amount detecting circuit and an antenna toner remaining amount detecting circuit are provided, and when the toner remaining amount is large, the antenna toner remaining amount detecting circuit is provided. The circuit is selected to calculate the remaining amount of toner, and when the remaining amount of toner is small, the optical remaining amount detection circuit is selected to calculate the remaining amount of toner. It can detect the remaining amount linearly and sequentially, and even when the amount of toner is small, it can display the accurate amount of remaining toner. Therefore, usability can be improved.

In this embodiment, the remaining toner amount is displayed in six levels, but the present invention is not limited to this, and may be other than six levels.

Embodiment 2 Next, a second embodiment of the present invention will be described with reference to FIG.

The configuration of the present embodiment is a modification of the method of displaying on the toner remaining amount display 23 of the CPU 25a used in the first embodiment. The use of both the optical type toner remaining amount detection circuit 22 and the antenna type toner remaining amount detection circuit 20 is the same, and a description thereof will be omitted.

The CPU 25a in the controller 25 has dual information of a toner remaining amount signal SNSA detected by an optical type developer remaining amount detecting device and a toner remaining amount signal SNSB detected by an antenna type developer remaining amount detecting device. By
The remaining toner amount to be displayed on the remaining toner indicator 23 is determined.

The toner remaining amount display indicates a predetermined toner remaining amount range, and can be displayed in increments of 1%. For example, the display is updated to display “45% to 65%” once, and to display “44% to 64%” when the predetermined toner amount decreases.

The CPU 25a controls each developing cartridge 11
When a to 11d are set at predetermined positions where a development process is performed, the light transmission amount (transmission time) is measured by an optical method, and the calculation is performed by a predetermined calculation formula to obtain the light transmission amount (transmission time). Is calculated. After that, the calculated data is stored in the RAM 25b as a toner remaining amount range in consideration of a predetermined variation width.

Next, at the timing when the developing bias is applied to the developing roller 3, the remaining amount of toner is detected by the antenna system. In the detection of the remaining amount of toner by the antenna method, a plurality of samplings are performed in the first detection sequence to detect a voltage. The data is temporarily stored in the RAM 25
b. Thereafter, an averaging process of the stored plurality of detected voltage values is performed, and the averaged detected voltage value is calculated by a predetermined formula to calculate toner remaining amount data corresponding to the voltage value. It is stored in the RAM 25b. After that, the calculated data is stored in the RAM 25b as a toner remaining amount range in consideration of a predetermined variation width.

The CPU 25a transmits a signal so as to be displayed on the toner remaining amount display 23 in accordance with the antenna type developer remaining amount detecting device until the lower limit of the toner remaining amount display width becomes 25%. . In other words, until the detected value in FIG.
A signal is transmitted to the remaining toner indicator 23 so as to display “0%”. Thereafter, when the detected value is Vb ′, a signal is transmitted to the toner remaining amount display 23 so that the remaining amount of toner is displayed as, for example, “65% to 85%”. When the detected value is Vc ′, the remaining toner amount is set to “25”.
A signal is transmitted to the toner remaining amount indicator 23 so as to display “% to 45%”. Vb ′ indicates an arbitrary voltage between Va ′ and Vc ′, and “8” according to the fluctuation of Vb ′.
From 5% to 100% display to 25% to 45% display, the remaining toner amount is displayed in steps of 1%.

After the lower limit value of the toner remaining amount display width reaches 25%, the remaining amount of toner is "25% to 45%" until the optical toner amount detecting circuit 22 detects the remaining toner amount of 25%.
Continue to be displayed. When the optical toner remaining amount detection circuit 22 detects the remaining toner amount of 25%, a signal is thereafter transmitted to be displayed on the toner remaining amount display 23 in accordance with the optical toner remaining amount detection circuit 22. When the remaining toner amount of 25% is detected, the display indicates “2” in consideration of a predetermined variation range.
2% to 28% "is displayed. Thereafter, until the lower limit of the toner remaining amount display width reaches 0%, the toner remaining amount is sequentially displayed in increments of 1%.

In this manner, it is possible to linearly detect from 100% of the remaining amount of toner to no remaining amount of toner, and it is possible to improve usability for a cartridge which is a replacement part of a laser printer or the like. .

In the above embodiment, the case where the present invention is applied to an electrophotographic image forming apparatus provided with a developing cartridge has been described. However, the technical idea of the present invention will be described at least by the electrophotographic photosensitive member and the developing device. The present invention can be applied to a process cartridge detachably mounted on the main body of an electrophotographic image forming apparatus, and an electrophotographic image forming apparatus including the process cartridge.

[0058]

As is apparent from the above description, according to the developer remaining amount detecting device, the developing device, the cartridge and the electrophotographic image forming apparatus of the present invention, light is incident on the developer container, First detecting means for detecting the remaining amount of the developer in the developer container by receiving light transmitted through the developer container, and an electrode provided in the developer container or in the vicinity of the developer container, A second detection unit that detects a remaining amount of the developer in the developer container by detecting a capacitance of a developer existing between the developer carrier and the electrode;
And selectively using the first detection means or the second detection means in accordance with the remaining amount of the developer, so that the remaining amount of the developer is changed from full to empty. The amount can be detected sequentially and accurately, and usability can be improved.

[Brief description of the drawings]

FIG. 1 is a schematic block diagram showing an embodiment of a developer remaining amount detecting device according to the present invention.

FIG. 2 is a schematic configuration diagram showing one embodiment of an electrophotographic image forming apparatus according to the present invention.

FIG. 3 is an explanatory diagram showing a relationship between a light detection waveform and a toner remaining amount characteristic in an optical type toner remaining amount detection circuit.

FIG. 4 is a diagram showing a toner remaining amount detection characteristic of the developer remaining amount detecting device in the first embodiment.

FIG. 5 is a diagram illustrating a toner remaining amount detection characteristic of a developer remaining amount detecting device according to a second embodiment.

[Description of Signs] 1 Laser unit (electrostatic latent image forming means) 3 Developing roller (developer carrier) 11a, 11b, 11c, 11d Developing cartridge 13 Antenna electrode 17 Developer container 15 Mounting means 20 Antenna type toner remaining amount Detection circuit 22 Optical type toner remaining amount detection circuit 22a LED 22b Optical sensor 23 Toner remaining amount indicator

Claims (18)

[Claims] 1. A developing device comprising a developer for developing an electrostatic latent image formed on an electrophotographic photosensitive member, and a developer carrying member for transporting the developer to the electrophotographic photosensitive member. An electrophotographic image forming apparatus including a developing device having a developer container, a developer remaining amount detecting device for detecting a developer remaining amount in the developer container, wherein light is incident on the developer container, A first detection unit that detects the remaining amount of the developer in the developer container by receiving light transmitted through the developer container, and an electrode provided in the developer container or in the vicinity of the developer container. And a second detection unit for detecting a remaining amount of the developer in the developer container by detecting a capacitance of a developer existing between the developer carrier and the electrode. The first detecting means or the second detecting means according to the remaining amount of the medicine. Developer remaining amount detecting apparatus characterized by selectively using. 2. The developer remaining amount detecting device according to claim 1, wherein the first detecting means is used when the remaining amount of the developer is at most half the full amount or less. 3. The developer remaining amount is at least one fifth of the full amount.
2. The developer remaining amount detecting device according to claim 1, wherein said second detecting means is used. 4. The developer remaining amount detecting device according to claim 1, wherein the electrophotographic image forming apparatus has a plurality of developing devices, and the number of the electrodes is at most less than the number of the developing devices. apparatus. 5. An electrophotographic image forming apparatus main body,
A developer container containing a developer for developing the electrostatic latent image formed on the electrophotographic photosensitive member, and a developer carrier for transporting the developer to the electrophotographic photosensitive member; A developer remaining amount detecting device for detecting a remaining amount of the developer in the developer container, wherein the developer remaining amount detecting device makes light incident on the developer container, A first detecting unit for detecting a remaining amount of the developer in the developer container by receiving light transmitted through the developer container; and an electrode provided in the developer container or in the vicinity of the developer container. Second detection means for detecting the remaining amount of the developer in the developer container by detecting the capacitance of the developer existing between the carrier and the electrode;
Wherein the first detecting means or the second detecting means is selectively used in accordance with a remaining amount of the developer. 6. The developing device according to claim 5, wherein the first detecting means is used when the remaining amount of the developer is at most half or less of the full amount. 7. The developer remaining amount is at least one fifth of the full amount.
6. The developing device according to claim 5, wherein said second detecting means is used. 8. A cartridge detachable from a main body of an electrophotographic image forming apparatus, comprising: (a) an electrophotographic photosensitive member;
(B) a developer containing a developer for developing the electrostatic latent image formed on the electrophotographic photosensitive member, and a developer including a developer carrier for transporting the developer to the electrophotographic photosensitive member; A developing device having a container, and (c) a developer remaining amount detecting device for detecting a remaining amount of the developer in the developer container, wherein the developer remaining amount detecting device includes the developer container. And detecting the remaining amount of the developer in the developer container by receiving light transmitted through the developer container.
By providing an electrode in the developer container or in the vicinity of the developer container, and detecting the electrostatic capacity of the developer existing between the developer carrier and the electrode by detecting the electrostatic capacity of the developer. And a second detecting means for detecting the remaining amount of the developer in the container, wherein the first detecting means according to the remaining amount of the developer,
Alternatively, the cartridge selectively uses the second detecting means. 9. A cartridge detachably mountable to the main body of an electrophotographic image forming apparatus, wherein (a) a developer is stored for developing an electrostatic latent image formed on an electrophotographic photosensitive member, and the developer is transferred to the electrophotographic image forming apparatus. A developing device having a developer container provided with a developer carrier for transporting the developer to the photographic photoreceptor; (b) a developer remaining amount detecting device for detecting the remaining amount of the developer in the developer container; The developer remaining amount detection device detects the remaining amount of the developer in the developer container by making light incident on the developer container and receiving the light transmitted through the developer container. A first detection unit, and an electrode provided in the developer container or in the vicinity of the developer container, and detecting an electrostatic capacitance of a developer existing between the developer carrier and the electrode by detecting the capacitance. Second detecting means for detecting the remaining amount of the developer in the developer container; Wherein the first detection means or the second detection means is selectively used in accordance with the remaining amount of the developer. 10. The cartridge according to claim 8, wherein the first detecting means is used when the remaining amount of the developer is at most half or less of the full amount. 11. The cartridge according to claim 8, wherein the second detection unit is used when the remaining amount of the developer is at least one fifth or less of the full amount. 12. An electrophotographic image forming apparatus for forming an image on a recording medium, comprising: (a) an electrophotographic photosensitive member;
(B) an electrostatic latent image forming means for forming an electrostatic latent image on the electrophotographic photosensitive member; and (c) a developer for developing the electrostatic latent image formed on the electrophotographic photosensitive member. A developing device having a developer container having a developer carrying member for housing and transporting the developer to the electrophotographic photosensitive member; and (d) detecting a remaining amount of the developer in the developer container. A developer remaining amount detecting device, wherein the developer remaining amount detecting device is configured to irradiate light to the developer container and receive light transmitted through the developer container, thereby receiving the developer container. First detecting means for detecting the remaining amount of developer in the developer container;
Alternatively, an electrode is provided in the vicinity of the developer container, and a remaining amount of the developer in the developer container is detected by detecting a capacitance of a developer existing between the developer carrier and the electrode. 2. An electrophotographic image forming apparatus, comprising: a first detection unit and a second detection unit that selectively use the first detection unit or the second detection unit according to a remaining amount of a developer. 13. An electrophotographic image forming apparatus for detachably mounting a cartridge and forming an image on a recording medium, comprising: (a) an electrophotographic photosensitive member; and an electrostatic latent member formed on the electrophotographic photosensitive member. Containing a developer for developing an image, a developing device having a developer container having a developer carrier for transporting the developer to the electrophotographic photoreceptor;
Mounting means for removably mounting a cartridge having: (b) a developer remaining amount detecting device for detecting the remaining amount of developer in the developer container; A detecting device configured to detect light remaining in the developer container by irradiating light to the developer container and receiving light transmitted through the developer container; An electrode is provided in the developer container or in the vicinity of the developer container, and the remaining amount of the developer in the developer container is detected by detecting the capacitance of the developer existing between the developer carrier and the electrode. And a second detecting means for detecting the remaining amount of the developer, wherein the first detecting means or the second detecting means is selectively used according to the remaining amount of the developer. apparatus. 14. An electrophotographic image forming apparatus for detachably mounting a cartridge and forming an image on a recording medium, wherein: (a) developing an electrostatic latent image formed on the electrophotographic photosensitive member; Mounting means for removably mounting a cartridge having a developing device having a developer container having a developer carrier for storing the developer and transporting the developer to the electrophotographic photosensitive member; b) a developer remaining amount detecting device for detecting a remaining amount of the developer in the developer container, wherein the developer remaining amount detecting device emits light to the developer container, First detecting means for detecting the remaining amount of the developer in the developer container by receiving light transmitted through the developer container, and an electrode provided in the developer container or in the vicinity of the developer container, There is a gap between the developer carrier and the electrode. Second detecting means for detecting the remaining amount of the developer in the developer container by detecting the capacitance of the existing developer, and the first detecting means according to the remaining amount of the developer. Or an electrophotographic image forming apparatus, wherein the second detecting means is selectively used. 15. The electrophotographic image forming apparatus according to claim 12, wherein the first detecting means is used when the remaining amount of the developer is at most half or less of the full amount. 16. The electrophotographic image forming apparatus according to claim 12, wherein the second detecting means is used when the remaining amount of the developer is at least one fifth or less of the full amount. apparatus. 17. The electrophotographic image forming apparatus according to claim 12, wherein the electrophotographic image forming apparatus has a plurality of the developing devices, and the number of the electrodes is at most less than the number of the developing devices. . 18. The apparatus according to claim 1, wherein the electrophotographic image forming apparatus has a plurality of the cartridges, and the number of the electrodes is at most less than the number of the cartridges.
The electrophotographic image forming apparatus according to 3 or 14.