JPH08114977A - Developing method and device - Google Patents

Abstract

PURPOSE: To detect the remaining amount and consumption of developer by allowing an electrode having a dielectric layer on the surface to press-contact with a developer carrier and detecting capacitance between the electrode and the developer carrier. CONSTITUTION: A magnet 5 is installed in a developing sleeve 3 and toner T is held thereon and carried to the side of a photoreceptor drum. A voltage applying means 6 composed of AC and DC power sources 11 and 10, as a developing electric field generating means for developing an electrostatic latent image on the drum is connected to the sleeve 3 and controlled by a controller 9. Then, a conductive layer is formed on the surface of urethane rubber on the side of a developing blade 1 in a rubbing part 4 and connected to a residual toner detecting circuit 12. It detects a change in the thickness of an insulating toner layer on the developing sleeve 3 as the change in the capacitance between the conductive layer and the sleeve 3.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a developing method and apparatus for forming a latent image on an image bearing member such as an electrophotographic photosensitive member or an electrostatic recording dielectric member and visualizing the latent image. is there.

[0002]

2. Description of the Related Art As an output means of an external device such as a computer or a copying machine, an image forming apparatus using an electrophotographic method as shown in FIG. 9 has been proposed. Electrophotographic photosensitive member 100 which is usually in the shape of a drum as a latent image carrier
Are uniformly charged by the primary charger 117. Next, the exposure device 123 irradiates the photoconductor 100 with light corresponding to the image information input from the external device to form a latent image. In the developing device 140, the electrostatic latent image on the photosensitive drum 1OO is reversely developed by the developer T having the same polarity as that of the primary charger 117 to form a visible image, that is, a toner image. The toner image is transferred to the transfer material P by the transfer charger 114. The transfer material P is separated from the photoconductor 100, and then the fixing device 12
After being conveyed to No. 6, it becomes a permanent image after fixing. On the other hand, the developer T on the photosensitive drum 100 that remains without being transferred by the transfer charger 114 is removed by the cleaning device 116,
The photosensitive drum 100 is subjected to the next image forming process.

The developing device 140 shown in FIG. 9 will be described in detail with reference to FIG. The developing device has a developing container 140a containing a toner T which is an insulating one-component developer. In this example, the toner T is a negatively chargeable magnetic toner that is negatively chargeable and contains a magnetic material. Further, the developing device 1
Reference numeral 40 denotes a conductive cylindrical sleeve having a diameter of 16φ and made of a non-magnetic metal such as aluminum or stainless steel containing a magnet roll, and is arranged at a constant distance from the sleeve by a gap regulating member (not shown). A magnet roller 104, which is a magnetic field generating means, is concentrically arranged in the developing sleeve 102 with a gap maintained. The magnet roller 104 is fixed to the image forming apparatus and is not rotated, and the developing sleeve 102 rotates around the built-in magnet roller 104 to convey the developer T.

The magnet roller 104 is provided with four magnetic poles S1, S2, N1 and N2 as shown in the figure.
The magnetic pole S1 is a developing pole, the magnetic pole N1 is a toner amount regulating pole, and the magnetic pole S is
Reference numeral 2 is a pole for taking in and carrying toner, and magnetic pole N2 is a pole for preventing toner blowout.

An elastic blade 103 is fixed above the developing sleeve as a toner amount regulating member and hangs down on the developing sleeve 102 and elastically abuts on the developing sleeve 102 to regulate the toner on the developing sleeve 102 to form a thin toner layer. Is defined and the amount of toner conveyed to the developing area is regulated. The amount of toner conveyed to the developing area is determined by the contact pressure and contact length of the elastic blade 103 that contacts the developing sleeve 102. Conventionally, the amount of transported toner is 1. per unit surface area of the developing sleeve 102. O-2. It is regulated to about Omg / cm ² .

An electrode rod 105 (hereinafter abbreviated as an antenna electrode) for detecting the remaining amount of toner is provided behind the developing sleeve 102.
The developing sleeve 102 is arranged in parallel with the developing sleeve 102 with a constant gap.

The toner conveyed to the developing area is
By the developing electric field generated by the developing bias applied between the developing sleeve 102 and the photosensitive drum 1OO, the developing sleeve 1
It flies from 02 onto the photosensitive drum 100 rotating in the direction of arrow A, adheres to the latent image on the photosensitive drum 100, and visualizes the latent image as a toner image.

Here, the toner remaining amount detection will be described in detail. The antenna electrode 105 is a conductive developing sleeve 10.
It is arranged with a constant gap between the two and insulating toner or air is present in the middle, so that it functions as a condenser. When the toner is sufficiently present in the developing container 140a, the antenna electrode is in the toner, and therefore the dielectric constant of the toner forms a capacitor having a large electrostatic capacitance. However, when the toner amount in the developing container 14Oa becomes small, a gap is generated between the antenna electrode and the developing sleeve, and the relative dielectric constant of air is small, so that the capacitance of the capacitor becomes small.

The antenna electrode is electrically connected to the remaining amount detecting circuit shown in FIG. The remaining amount detecting circuit detects the electrostatic capacity between the antenna electrode and the developing sleeve as a change in the electrostatic capacity by supplying the same AC signal, for example, a rectangular wave, to the comparison capacitor C1. When the electrostatic capacity between the antenna electrode and the developing sleeve becomes less than the electrostatic capacity of the comparison capacitor, the output of the comparator is inverted from high level to low level. That is, when an image defect occurs due to insufficient toner supply, the capacitance between the antenna electrode and the developing sleeve is measured in advance,
The remaining toner amount is detected by setting the electrostatic capacity of the comparison capacitor.

[0010]

In the above-mentioned conventional apparatus, by detecting the remaining amount of toner by the antenna electrode, it has succeeded in preventing a defective image such as white lines and white spots due to insufficient toner supply with a simple structure. There is. However, arranging the antenna electrodes has caused the following problems.

First, the antenna electrode needs to be arranged in the developing device with high accuracy. This is because the position of the antenna electrode greatly affects the electrostatic capacitance with the developing sleeve. In order to prevent the malfunction of the remaining toner amount detection, it is necessary to make the electrostatic capacity constant or adjust each of the comparison capacitors. Here, in order to make the capacitance constant, it is necessary to accurately determine the distance and angle (parallel to the developing sleeve) with the developing sleeve, but this leads to an increase in cost. Even if each of the comparative capacitors is adjusted, the number of inspection steps during assembly is increased, and the cost is similarly increased.

Next, the antenna electrode hinders the toner flow in the developing container. In particular, if the antenna electrode and the wall of the developing container are clogged with toner when the toner remaining amount decreases, it is difficult to replenish the toner to the developing sleeve. A streak image occurs and a normal image cannot be output.

In the present situation, in order to solve the above problems, it is necessary to finely adjust the antenna position during product design and assembly, which inevitably leads to an increase in cost.

[0014]

To solve the above problems, the following developing method and developing apparatus are used. An electrode having a dielectric layer on the surface is pressed against a developer carrier, a voltage having a polarity opposite to that of the developer is applied to the electrode, and the developer charged to a regular charging polarity is attracted toward the electrode to charge the developer. And the electrostatic capacity between the electrode and the developer carrier to detect the remaining amount or consumption of the developer.

In a developing device used in an image forming apparatus such as an electrophotographic system and an electrostatic recording device, a dielectric layer is formed on the surface of a developer regulating member which is pressed against a developer carrier to form a thin layer of the developer. And an electrode having a polarity opposite to that of the developer is applied to the electrode to attract the developer charged to a regular charging polarity toward the electrode to promote the charging of the developer and to develop the electrode and the developer. A developing device characterized in that the remaining amount or the consumption amount of the developer can be detected by detecting the electrostatic capacity between the agent carriers.

By using the developing method of the present invention, the position of the remaining toner amount detecting antenna electrode can be easily determined by the thickness of the dielectric, and the inspection process at the time of manufacturing can be omitted and the yield can be improved. It became possible and the cost was reduced. In addition, since the amount of toner that hinders the toner flow in the developing container is reduced, it becomes possible to stably supply the toner to the developing sleeve, and the image is stabilized.

By applying a voltage having a polarity opposite to that of the developer to the electrode, the developer charged to the regular charging polarity is attracted, and the developer charged to the opposite polarity is pressed on the developer carrying member. Promotes triboelectric charging of the toner,
It is possible to realize uniform charging of the toner.

[0018]

【Example】

 (Embodiment 1) FIG. 1 shows a first embodiment of the present invention.

In FIG. 1, reference numeral 1 is a developing blade which is a developer regulating member. The developing blade 1 in the figure is a supporting metal plate 2.
Made of 1 mm thick urethane rubber attached to
The developing sleeve 3 having an outer diameter of 16 mm, which is a developer carrier, is in contact with the developing sleeve 3 in a direction opposite to the rotation direction of the developing sleeve 3.
Here, urethane rubber is used as the developer regulating member, but basically any material may be used as long as the toner can be regulated to form a thin toner layer uniformly. In this embodiment, the rubbing portion between the developing sleeve 3 and the developing blade 1 is about 2 mm, and the contact pressure per unit longitudinal direction is about 20 g / cm. The peripheral speed of the developing sleeve 3 is about 100 mm / sec.

Further, in the present embodiment, since the toner remaining amount detecting member is integrated with the regulating member, there is no antenna electrode near the developing sleeve as in the conventional case.

In this embodiment, the toner T is an insulating toner having a negative polarity. For example, 60w of magnetite is added to a binder resin whose main component is styrene-acrylic copolymer.
t% and a silica fine particle that is hydrophobized to increase fluidity, based on an insulating magnetic toner having a volume resistance of about 10 ¹³ Ωcm and containing 1 wt% of a metal complex salt of a monoazo dye as a negative charge control material. O. to the toner weight. 4w
It is possible to use the one in which t% is externally added.

A magnet 5 is installed inside the developing sleeve 3, holds the toner T on the developing sleeve 3, and conveys it to the photosensitive drum side which is arranged with a gap of 300 μm from the developing sleeve 3. The toner on the developing sleeve 3 is regulated by the developing blade 4 while being conveyed, and is uniformly applied onto the developing sleeve 3. The toner T conveyed on the developing sleeve 3 is developed on the photosensitive drum in the developing area where the developing sleeve 3 and the photosensitive drum face each other. The toner that did not contribute to the development remains on the developing sleeve 3,
It is collected from the opening below the developing sleeve 3.

An AC power supply 11 is provided on the developing sleeve 3 as a developing electric field generating means for developing the electrostatic latent image on the photosensitive drum.
And a voltage applying means 6 composed of a DC power source 10 is connected,
The voltage applying means is controlled by the controller 9. In this embodiment, the DC voltage is −500 V and the AC voltage is 1
A developing bias of 640 volts (Vpp) and an alternating frequency of 1800 Hz was used.

The toner remaining amount detection in the present invention will be described in detail with reference to FIG. FIG. 6 is an enlarged view of the rubbing portion 4 of the developing blade 1 and the developing sleeve 3.

As shown in FIG. 6, a conductive layer 1b having a width of 2 mm is formed on the surface of the urethane rubber of the rubbing portion 4 on the side of the developing blade 1. In this embodiment, polyethylene having carbon dispersed therein to reduce the resistance is used for the conductive layer 1b. The conductive layer 1b is connected to the toner remaining amount detecting circuit 12 as shown in FIG. A dielectric layer 1c is formed on the surface of the conductive layer 1b. As the dielectric layer 1c, a material having a high insulating property, flexibility, and charging the toner to a regular polarity (negative polarity in this embodiment) in a charging series is suitable. In this example, nylon was coated on the conductive layer 21 to a thickness of 50 μm.

The toner remaining amount detecting circuit detects a change in the thickness of the insulating toner layer on the developing sleeve 3 as a change in the electrostatic capacitance between the conductive layer 1b and the developing sleeve 3.
This will be described below with reference to FIG. Between the conductive layer 1b and the developing sleeve 3, the electrostatic capacity C1 by the toner layer and the dielectric layer 1c are provided.
Is present and is grounded via a resistor R. When a developing bias is applied to the developing sleeve 3 from the developing power sources 10 and 11, a current i corresponding to the impedance of C1, C2, and R flows.

Here, when the image is output by the image forming apparatus equipped with the main developing device and the toner is consumed, C
As for the changes of 1 and C2, first, C2 is determined by the dielectric constant, thickness, etc. of the dielectric layer 1c, and is unchanged with respect to the toner consumption. On the other hand, the size of C1 depends on the toner layer thickness, and as the toner is consumed and the toner layer thickness on the developing sleeve becomes thinner, C1 becomes larger. Therefore, the change in C1 can be detected by detecting the combined capacitance C1 · C2 / (C1 + C2) of C1 and C2, and the toner layer thickness and the toner consumption amount can be detected.

As shown in FIG. 5, by consuming a certain amount of toner, the toner layer on the developing sleeve 3 becomes thin (a), and the electrostatic capacitance C1 of the toner layer becomes large (b). At this time, the impedance due to C1, C2, and R decreases, the current i increases, and the voltage Va generated in the resistor 15 increases. This voltage Va reflects the toner layer thickness (c).

On the other hand, the comparison capacitor Cr is preset to the combined electrostatic capacitance of C1 and C2 when an image defect occurs due to insufficient toner supply, and is grounded via a similar resistor R. Therefore, by comparing Va and Vb with the comparator 13, it is possible to detect the toner supply shortage. C1 and C2 increase, and voltage Va> V
When it becomes b, the output signal Z of the comparator 13 is switched from the low level to the high level, and it is possible to inform the user that the toner remaining amount is insufficient.

This is the principle of toner remaining amount detection in the present invention. Next, as another effect of the present invention, uniform charging of toner will be described.

The developing sleeve 3 has a DC voltage of -5OOV from the DC power source 10 and an AC voltage of 164 from the AC power source 11.
A developing bias of 0 volt (Vpp) and an alternating frequency of 1800 Hz is applied. That is, when the developing bias is applied, a large electric field is generated between the conductive layer 1b on the developing blade and the developing sleeve 3 which are grounded via the resistor R.

Hereinafter, the charging of the toner will be described in detail with reference to FIG. First, the toner T on the developing sleeve 3 is charged by frictional charging. At this time, the toner rubbed against the developing sleeve 3 is charged to a negative polarity as normal by the charge control material in the toner (referred to as a regular toner T1). However, about 10% of the toner T is contained in the developing sleeve 3.
Instead, the toner is frictionally charged with each other, and the reversal toner T is positively charged and has a polarity opposite to the regular charging polarity.
2 occurs. Since the electric field E has not been applied in the past, the reversal toner T2 is conveyed to the developing area while having the toner distribution mixed with the regular toner T1, and the toner is jetted to the photosensitive drum by the developing bias to perform the development. Was there.
Therefore, the image is fogged in the non-image area and the image quality is degraded.

On the other hand, according to the present invention, the electric field E is applied to the rubbing portion 4, so that the negatively charged regular toner T1 is attracted to the side 1b of the developing blade having a higher potential. On the contrary, the reversal toner T2 is pressed against the developing sleeve 3 side, and the toner that is originally rubbed against the developing sleeve 3 is recharged to the regular negative polarity by the charge control material. As a result, the amount of the reversal toner T2 in the toner T is reduced, and a high-quality image with less fog is obtained in the output image.

Here, the DC voltage has the effect of pressing the reversal toner against the developing sleeve 3 and recharging it to the normal polarity (negative polarity), while the AC voltage agitates the toner and facilitates its movement in the toner layer. Further, it is effective in further promoting uniform charging of the toner, erasing the charging history of the toner, and preventing ghost.

Therefore, according to the present embodiment, by integrating the antenna electrode for detecting the remaining amount of toner and the developing blade, it is possible to easily improve the positional accuracy when the antenna electrode is attached, and the toner flow by the antenna electrode is also improved. Sexual inhibition has also been resolved. Further, by applying an electric field when the toner is charged, the reversed toner is attracted to the developing sleeve 3 and recharged to the normal polarity, so that the reverse fog can be reduced from the output image.

In this embodiment, the conductive layer and the dielectric layer are provided on the conventional elastic blade to form a three-layer structure. However, for the sake of simplicity, the conductive blade is provided on the back surface of the elastic blade to provide two layers. There is no problem with the structure. Furthermore,
The dielectric layer on the surface of the conductive layer prevents development bias leakage,
Moreover, the purpose is to improve the charge amount of the toner,
Regarding the detection of the remaining amount of toner, the electrostatic capacity of the toner layer can be measured as long as the developer regulating member has the conductive layer or even the conductive member. Therefore, by omitting the dielectric layer on the surface of the conductive layer, the remaining toner amount can be detected more easily.

(Embodiment 2) FIG. 4 is a conceptual diagram showing the vicinity of the developing blade and the remaining toner amount detection circuit in the developing method and developing apparatus of the present invention in Embodiment 2. This example is the same as Example 1 except that during development (during paper passing), electric power is supplied to the electrodes on the developing blade by a high-voltage power source to stir the toner layer on the developing blade more strongly than in Example 1. On the other hand, when the paper is not passed, the upper electrode (conductive layer 1b) of the developing sleeve 3 is connected to the electrostatic capacitance detection circuit, so that the developing sleeve 3
The upper toner layer thickness is detected to detect the remaining amount of toner.

The high-voltage power supplies 18 and 19 supply power to the conductive layer 1b through the switch 17, and the switch 17 and the high-voltage power supplies 18 and 19 are controlled by the controller 9. An electrostatic capacitance detection circuit for detecting a change in electrostatic capacitance is connected to the conductive layer 1b and the comparison capacitor 14. The other structure of this embodiment is basically the same as that of the first embodiment, and the same reference numerals as those in FIG. 3 represent the same members.

First, the controller 9 electrically connects the high-voltage power supplies 18 and 19 to the conductive layer 1b when the paper is passed. The high-voltage power supply is generated by superimposing a DC voltage of + 500V having a polarity opposite to that of the toner from the DC power supply 19 and an AC voltage of 1 kV (Vpp) from the AC power supply 18. Here, the DC voltage has the effect of pressing the reversal toner against the developing sleeve 3 and recharging it to the normal polarity, while the AC voltage stirs the toner and makes it easier to move in the toner layer, so that the toner is uniformly charged. It has the effects of further promoting, erasing the charge history of the toner, and preventing ghost. Therefore, in this embodiment, since the DC voltage and the AC voltage are supplied by the high voltage power source, it is possible to charge the toner with a larger electric field as compared with the first embodiment, so that the toner can be further uniformly charged and the reversal fog is caused. A good image with no ghosts was obtained.

Next, since it is not necessary to uniformly charge the toner when the paper is not passed, the controller 9 switches the switch 17 to connect the conductive layer 1b and the capacitance detection circuit 1. Similar to the first embodiment, the electrostatic capacitance C1 due to the toner layer and the electrostatic capacitance C2 due to the dielectric layer 1c exist between the conductive layer 1b formed on the urethane developing blade as the elastic body and the developing sleeve 3. . As the toner is consumed and the toner layer on the developing sleeve 3 becomes thinner, C1 becomes larger and C1 becomes larger.
When the combined capacitance of 1 and C2 becomes larger than Cr, the output signal Z of the comparator is inverted from low level to high level. C when an image defect occurs due to insufficient toner amount
By setting the size of Cr in advance to the combined electrostatic capacitance of 1 and C2, it is possible to notify the user of the image forming apparatus of the toner amount shortage by the output signal Z, and the output of the defective image can be prevented. It became possible to prevent it.

In the second embodiment, a larger electric field is generated between the developing blade 1 and the developing sleeve 3 as compared with the first embodiment, so that the dielectric sleeve 1c and the developing sleeve 3 having low resistance are electrically conductive due to the dielectric breakdown. A leak is likely to occur between the layers 1b. Therefore, as shown in FIG. 2, by making the conductive layer 1b shorter than the toner coat length, it is possible to prevent the high resistance toner layer from leaking to the developing sleeve 3. At this time, if the conductive layer 1b is longer than the image forming portion on the photosensitive drum in the longitudinal direction of the developing sleeve 3, there is no problem on the image.

(Embodiment 3) FIG. 7 shows another embodiment of the developing method of the present invention.

In Example 1 and Example 2, the conductive layer and the dielectric layer were provided on the developer regulating member to detect the remaining amount of toner, but any existing member arranged near the developer carrying member may be used. It is not necessarily on the developer regulating member, and for example, in the case of color development, a non-magnetic one-component toner is supplied to the developer carrying member, and a conductive layer and a dielectric layer similar to those of the present embodiment are provided on the developer supplying roller. It is also possible to detect the remaining amount of toner by providing, and the toner layer is thicker and easier to detect than the developer regulating member.

In the third embodiment, the remaining amount detecting electrode is formed not on the developing blade but on the supply roller 20 for supplying the developer to the developing sleeve 3. The supply roller 20 is pressed against the developing sleeve 3 and driven in a counter direction with the developing sleeve 3 at a peripheral speed ratio of 50%, so that the toner T is triboelectrically charged between the supplying roller 20 and the developing sleeve 3 into toner. An electric charge is applied, and the toner is applied to the developing sleeve 3 by the image force generated by the electric charge. The applied toner T is conveyed by a developing sleeve, and after being formed into a uniform thin layer by an ordinary developing blade 21 made of a urethane elastic body, it is conveyed to a developing area.

FIG. 8 shows a sectional view of the supply roller 20 and its vicinity. 2Oa is a cored bar made of a metal rod, which is driven in the direction C in the figure by an external motor (not shown). The cored bar 20a is electrically connected to the remaining amount detection circuit 12 as in the above embodiment. Reference numeral 20b denotes a conductive elastic body that allows the toner to rub evenly when pressed against the developing sleeve 3. Reference numeral 20c is a dielectric layer formed on the conductive elastic body, which prevents the developing bias from leaking to the supply roller 20 and makes it possible to give more charge to the toner by frictional charging. In this embodiment, the supply roller 20 is formed by coating 20b with ethylene propylene rubber having conductive carbon black fine particles dispersed therein, and with 2Oc, urethane resin having a thickness of 20 μm.

That is, the supply roller is in contact with the developing sleeve 3 via the toner T having a constant layer thickness, and the electrostatic capacity of the toner layer is changed by the toner remaining amount detection circuit 12 as in the above embodiment. It is possible to detect the toner shortage by measuring. Even with such a configuration, it is possible to detect the remaining toner amount without disposing the antenna electrode as in the above-described embodiment, and to invert by applying a voltage having a polarity opposite to that of the toner to the supply port. It was confirmed that a high-quality image with less reversal fog was obtained because the reversal toner was reduced by pressing the toner against the developing sleeve 3 to promote recharge to the normal polarity.

[0047]

By using the developing method or the developing apparatus according to the present invention, the position of the toner remaining amount detecting electrode can be easily determined, and the inspection process at the time of manufacturing can be omitted and the yield can be improved. The cost reduction was realized. In addition, since the amount of toner (antenna electrode) that hinders the toner flow in the developing container is reduced, it is possible to stably supply the toner to the developing sleeve, and the image is stabilized.

By applying a voltage having a polarity opposite to that of the developer to the electrode, the developer charged to the regular charging polarity is attracted, and the developer charged to the opposite polarity is pressed on the developer carrier. Promotes recharging to normal polarity,
It was possible to realize uniform charging of the toner. Along with this, it has become possible to obtain good images with less reversal fog.

Further, by providing a dielectric layer on the surface of the electrode,
It has become possible to prevent the development bias from leaking and improve the toner charge amount.

[Brief description of drawings]

FIG. 1 is a sectional view showing an embodiment of a developing device according to the present invention.

FIG. 2 is a front view of a developing blade according to the present invention.

FIG. 3 is a schematic diagram of a toner remaining amount detecting device used in Embodiment 1 of the present invention.

FIG. 4 is a schematic diagram of a toner remaining amount detecting device used in a second embodiment of the present invention.

FIG. 5 shows the toner layer thickness, the electrostatic capacitance, and the toner consumption amount.
Diagram showing changes in potential

FIG. 6 is an enlarged view of a developing blade and a developing sleeve sliding portion.

FIG. 7 is a sectional view of a developing device in Embodiment 3 of the present invention.

FIG. 8 is a schematic diagram of a supply roller according to a third embodiment of the present invention.

FIG. 9 is a diagram showing an example of a conventional image forming apparatus.

FIG. 10 is a diagram showing an example of a conventional developing device.

FIG. 11 is a schematic view of a conventional toner remaining amount detecting device.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Developing blade 1b ... Conductive layer 1c ... Dielectric layer 2 ... Conductive sheet metal 3 ... Conductive developing sleeve 10, 11 ... Developing power supply 12 ... Toner remaining amount detection circuit 20 ... Supply roller

Claims (8)

[Claims] 1. A residual amount or a consumption amount of a developer is detected by pressing a member having at least an electrode against a developer carrier and detecting an electrostatic capacitance between the electrode and the developer carrier. A developing method characterized by the above. 2. A residual amount or a consumed amount of the developer is detected by pressing an electrode having a dielectric layer on the surface thereof against a developer carrier and detecting the capacitance between the electrode and the developer carrier. A developing method characterized in that. 3. A voltage having a polarity opposite to the charge polarity of the developer is applied to the electrode to attract the developer charged to the regular charge polarity toward the electrode to accelerate the charge of the developer and to develop the electrode and the developer. A developing method characterized in that the remaining amount or the consumption amount of the developer is detected by detecting the electrostatic capacity between the agent carriers. 4. A latent image is formed on an image bearing member, and the latent image is developed using a developer on the developer bearing member.
In a developing device used in an image forming apparatus such as an electrophotographic system or an electrostatic recording device, a member having at least an electrode pressed against a developer carrier and an electrostatic capacitance between the electrode and the developer carrier are detected. And a means for detecting the remaining amount or consumption of the developer. 5. A latent image is formed on an image bearing member, and the latent image is developed using a developer on the developer bearing member.
In a developing device used in an image forming apparatus such as an electrophotographic system and an electrostatic recording device, an electrode having a dielectric layer on the surface pressed against a developer carrier and an electrostatic capacitance between the electrode and the developer carrier. And a means for detecting the remaining amount or the consumption amount of the developer, and a developing device. 6. The developing device according to claim 4, wherein the electrode is formed on a developer supply member that supplies the developer to the developer carrier. 7. The developing device according to claim 5, wherein the dielectric layer is formed on a developer supply member that supplies the developer to the developer carrier. 8. A developer carrying member for transferring a developer thinned by a developer regulating member to an electrostatic holding surface to form an electrostatic latent image as a visible image, the developer regulating member. Is
In the longitudinal direction of the developer carrying member, there is an electrode that is larger than the image region width and shorter than the developer coating length, and the electrode has a dielectric layer on the surface, and the dielectric layer is the longitudinal direction of the developer carrying member. Regarding the developing device, the developing device is longer than the electrode.