JPH05216385A - Electrophotographic device - Google Patents

Abstract

PURPOSE:To prevent free carriers generated by an exposure from remaining on a photosensitive body before an electrostatic charging process, and to reduce the fogging of an image by allowing deelectrification light with which the photosensitive body before the electrostatic charging process is irradiated, from a deelectrification means, to intermittently emit at speed faster than the moving speed of the photosensitive body, by means of the control of the deelectrification light. CONSTITUTION:Out of the contact area of the photosensitive drum 1 and toner, a deelectrification light control means 30 allows the deelectrification light of a deelectrification device 27 to be intermittently emitted at the speed sufficiently faster than the moving speed of the photosensitive drum, 1 so that the photosensitive drum 1 is irradiated and its surface is uniformly deelectrified. Since the free carriers generated by the deelectrification can be prevented from remaining on the photosensitive drum 1, it can be sufficiently charged without offsetting a charge obtained by electrostatic charging, by the free carriers, in the next electrostatic charging.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrophotographic apparatus provided with a discharging means for discharging the surface of a photosensitive member by irradiating the photosensitive member before the charging step with discharging light.

[0002]

2. Description of the Related Art Conventionally, in an electrophotographic apparatus such as a copying machine or a laser printer, the surface of the photosensitive member is charged by a charging roller or the like.
After being uniformly charged, the exposure device performs exposure according to the writing signal, and an electrostatic latent image is formed on the surface of the photoconductor. This electrostatic latent image is visualized as a toner image by the toner supplied from the developing device, and the toner image is transferred to a recording material or the like by a transfer roller.

The above-mentioned photosensitive member is continuously exposed by a static eliminator after being developed by a developing device and until next charged by a charging roller, for example, after being transferred by a transfer roller. As a result, the surface of the photoconductor is uniformly discharged, and the surface of the photoconductor is stabilized in preparation for the next charging.

Further, in recent years, by applying a voltage to a developing sleeve having a magnetic roller or the like inside thereof, the toner held on the developing sleeve is brought into contact with the photosensitive member, so that the surface of the photosensitive member is exposed via the toner. An electrophotographic apparatus that employs a method of injecting an electric charge to charge the surface of the photoconductor has also been proposed. In such an electrophotographic apparatus, the surface of the photoconductor is neutralized by continuously performing the exposure by the static eliminator outside the contact area between the photoconductor and the toner.

[0005]

However, in the electrophotographic apparatus using each of the charging methods as described above, even if the minimum current that the static eliminator lights up is passed and the static elimination is performed with the minimum light amount, the static elimination is performed. Free carriers generated by the irradiation of light remain on the surface of the photoconductor. Therefore, at the time of the next charging performed after the charge removal, the charge injected into the photoconductor is
Since the free carriers cancel each other out, the photoconductor cannot be sufficiently charged even when the static eliminator is used with the minimum amount of light, which causes a problem of image fog.

Further, in order to minimize the above-described image fogging, when the static eliminator is turned on with a light amount as small as possible, the light amount of the static eliminator is likely to vary, and the surface potential of the photoconductor is reduced. Since there are irregularities, there is a risk that an afterimage will occur.

[0007]

In order to solve the above-mentioned problems, the electrophotographic apparatus of the present invention comprises a charge removing means for a photoconductor from the completion of the developing process by the developing device to the start of the next charging process. In the electrophotographic apparatus for removing the charge on the surface of the photoconductor by performing the exposure by, the charge removal light applied to the photoconductor by the charge removing unit is intermittently turned on at a speed faster than the moving speed of the photoconductor. It is characterized in that a static elimination light control means is provided.

[0008]

According to the above construction, the charge eliminating light emitted from the charge eliminating means to the photoconductor from the end of the developing step to the start of the charging step is controlled by the charge eliminating light control means to be higher than the moving speed of the photoreceptor. By turning on the light intermittently at a high speed,
Even when the static eliminator is used in a stable light amount range, it is possible to prevent the free carriers generated by the exposure from remaining on the photoconductor before the charging step, and the image fog is reduced.
Furthermore, unlike the conventional method, to minimize image fogging, there is no need to use the static eliminator in a small light amount range,
Since the static eliminator can be used in a stable light quantity region, unevenness in the quantity of light of the static eliminator is reduced and unevenness of the surface potential of the photoconductor is also reduced, which in turn avoids the possibility of an afterimage.

[0009]

【Example】

[Embodiment 1] FIG. 1 to FIG. 7 showing an embodiment of the present invention.
The explanation is based on the following.

As shown in FIG. 2, the electrophotographic apparatus of this embodiment is provided with a cylindrical photosensitive drum (photosensitive member) 1 rotatable in the direction A in the apparatus. A developing device 2 is arranged on the right side of the photoconductor drum 1, an exposure device 7 and a charge eliminating device 27 are arranged in the photoconductor drum 1, and a transfer / fixing belt 8 is arranged above the photoconductor drum 1. It is set up.

The developing device 2 is provided with a developing tank 3 for storing the toner T and rotatably in the developing tank 3.
A stirring roller 4 that stirs the toner carrier 5, a toner carrier 5 disposed at a position facing the photosensitive drum 1 in the opening 3a of the developing tank 3, and a position below the toner carrier 5 in the opening 3a of the developing tank 3. It is composed of a doctor blade 6 fixedly mounted on the.

The toner carrier 5 extends along the longitudinal direction of the photosensitive drum 1 and has N polarity and S in the circumferential direction.
A magnetic roller 5a in which magnets with polarities are alternately arranged and a non-magnetic conductive member such as aluminum or martensitic stainless steel, and a developing device provided so as to cover the outer peripheral surface of the magnetic roller 5a. It is composed of a sleeve 5b.

The toner carrier 5 is the magnetic roller 5
The magnetic force of a attracts the toner T and holds it on the surface of the developing sleeve 5b, and the alternating magnetic field generated by the rotation of the magnetic roller 5a in the B direction causes the toner T to be in the rotational direction B of the magnetic roller 5a. B'in the opposite direction
It is designed to be conveyed in the direction. Further, the doctor blade 6 adjusts the carrying amount of the toner T, which is held on the surface of the developing sleeve 5b and is carried in the B ′ direction as described above, to a predetermined amount.

As shown in FIG. 4, the photosensitive drum 1 has a surface of an optically transparent cylindrical transparent support 1a,
A transparent conductive layer 1b made of a sputtered film such as In ₂ O ₃ or SnO ₂ ,
A photoconductive layer 1c made of a photoconductive material such as Se, ZnO, CdS, or amorphous Si is sequentially laminated.
In this embodiment, the transparent conductive layer 1b has a film thickness of
An In ₂ O ₃ layer having a thickness of 0.5 μm is formed, and an amorphous Si layer having a thickness of 3 μm is formed as the photoconductive layer 1c. On the other hand, the toner T is prepared by kneading resin such as styrene-acrylic copolymer with magnetic powder such as iron powder and ferrite, carbon black, etc.
It is composed of powder made into

As shown in FIG. 2, the exposure device 7 disposed in the photosensitive drum 1 is composed of an LED (Light Emitting Diode) array in which a short focus lens is combined with a light emitting diode. Light is emitted toward the developing device 2 in accordance with a write signal from an exposure control means (not shown).

Further, inside the photosensitive drum 1, below the exposure device 7, a static eliminator 27 made of, for example, an LED is installed. The static eliminator 27 is controlled by a static eliminator control means 30 described later so as to intermittently turn on at a speed sufficiently higher than the moving speed of the photosensitive drum 1. Such static elimination light control means 30 is shown in FIG.
As shown in (a), the power supply 28, the transistor 29, the resistor R, and the static eliminator 27 are connected in series,
By inputting the pulse signal A as shown in (b) to the transistor 29, the static eliminator 27 can be intermittently turned on. The irradiation of the static elimination light by the static elimination device 27 is performed after the exposure by the exposure device 7 is performed and a toner image is formed on the surface of the photosensitive drum 1.

The transfer / fixing belt 8 is formed in an endless belt shape using a film material mainly composed of a polyimide resin having excellent mechanical strength and high heat resistance. The transfer / fixing belt 8 is a transfer roller 9 made of a conductive elastic member disposed above the photosensitive drum 1.
A heating device 10 to be described later, which is arranged on the left side of the transfer roller 9 and slightly above, and a tension roller 11 which is arranged on the lower left side of the heating device 10.
It is wrapped around these so as to surround and from the outside. The transfer / fixing belt 8 is sandwiched between the photosensitive drum 1 and the transfer roller 9 by the photosensitive drum 1 and the transfer roller 9.

The heating device 10 is for heating and melting the toner T transferred onto the surface of the transfer / fixing belt 8 as will be described later, and has a planar shape on the alumina ceramic substrate.
It is composed of a ceramic heater in which a Mo-based heating resistor 10a is printed and a glass coat is printed and laminated thereon. The heating device 10 is configured to quickly raise the temperature to a predetermined heating temperature by energizing the heating resistor 10a, and this heating surface is transferred / fixed to the belt 8.
It is placed so as to be in direct contact with the surface of.

A pressure roller 12 that rotates while applying a pressing force in a direction toward the heating device 10 via the transfer / fixing belt 8 is provided on the upper portion of the heating device 10.
The pressure roller 12 sandwiches the transfer paper P conveyed by the transfer paper conveying means 14 described later at the pressure contact portion with the transfer / fixing belt 8. ..

Further, in the electrophotographic apparatus, as shown in FIG. 1, a cooling fan 24 for cooling the transfer / fixing belt 8 from the lower side, and the above-described static elimination light control means for controlling the lighting of the static elimination device 27. 30, a main motor 13 which is a drive source of the apparatus, and the above-mentioned transfer paper conveying means 14 which conveys the transfer paper P to a pressure contact portion between the transfer / fixing belt 8 and the pressure roller 12.
And a paper output means 21 for discharging the transfer paper P from inside the apparatus.

The transfer paper conveying means 14 is arranged above the photoconductor drum 1, the developing device 2 and the transfer / fixing belt 8 and has a transfer paper supply opening (not shown) as its constituent member. From the transfer / fixing belt 8 to the pressure contact portion of the pressure roller 12, a conveyance guide plate 15, a paper feed actuator 16 and paper feed rollers 18 and 18 arranged near the transfer paper supply opening. And the registration rollers 19 arranged on the way of the conveyance guide plate 15.
19 and a sheet feeding solenoid 20 that controls the rotation of the registration rollers 19 and 19.

The paper output means 21 is a transfer / fixing belt 8
It is disposed on the left side of the pressure contact portion between the pressure roller 12 and the pressure roller 12, and as its constituent member, connects the pressure contact portion between the transfer / fixing belt 8 and the pressure roller 12 to a transfer paper discharge opening (not shown). A paper output guide plate 22 forming a paper path, a paper output actuator 23 arranged in the vicinity of the pressure contact portion between the transfer / fixing belt 8 and the pressure roller 12, and a conveyance arranged on the end side of the paper output guide plate 22. And rollers 25, 25.

Next, the operation of the electrophotographic apparatus having the above structure will be described below.

First, the transfer paper feeding means (not shown)
When a sheet of transfer paper P is fed from the transfer paper supply opening,
When the leading edge of the transfer paper P pushes up the paper feed actuator 16, a paper feed detection switch (not shown) detects the supply of the transfer paper P and sends a paper feed detection signal to the main motor 13 to drive the drive source. The main motor 13 is driven to rotate. Next, the rotation of the main motor 13 is transmitted to the paper feed rollers 18 and 18 via a rotation transmission mechanism (not shown), whereby the paper feed rollers 18 and 18 are rotated, and the rotation of the paper feed rollers 18 and 18 is performed. Accordingly, the transfer paper P is conveyed to the registration rollers 19 and 19.

As described above, the registration roller 19.1
The transfer sheet P conveyed to the sheet 9 is transferred to the registration rollers 19 and 19
However, since the rotation is stopped by the control of the paper feeding solenoid 20, the transportation is temporarily stopped. At this time,
The sheet feeding rollers 18 and 18 are in a state of sandwiching the rear end side of the transfer sheet P, and because the resistance of the roller surface is small, slippage occurs on both sides of the transfer sheet P as the transfer sheet P stops being conveyed. It is in the state of having done.

Here, the electrophotographic apparatus is in a standby state,
If the print start signal is not generated within the predetermined time, the main motor 13 is stopped. On the other hand, when the print start signal is generated in the standby state, all the rotating parts other than the registration rollers 19 are rotated by the rotation transmission mechanism.

Next, the toner T will be described with reference to FIGS.
The developing process will be described.

First, the developing tank 3 is caused by an alternating magnetic field generated by the rotation of the magnetic roller 5a in the B direction (see FIG. 2).
As shown in FIG. 4, the toner T stored in the inside is held on the surface of the developing sleeve 5b, and at the same time, the developing sleeve 5b is held.
Is conveyed in the direction B ', which is opposite to the direction A, which is the rotation direction of the photosensitive drum 1. That is, in the contact area between the toner T held on the surface of the developing sleeve 5b and the photoconductor drum 1, the toner T charged by the developing sleeve 5b is rotatively conveyed toward the upstream portion in the photoconductor advancing direction to rotate the toner. A pool of T is formed. During this period, charges are injected from the developing sleeve 5b through the toner T into the photoconductive layer 1c on the surface of the photoconductor drum 1, and the photoconductive layer 1c is charged.
Is charged to substantially the same potential as the developing sleeve 5b. Therefore, in the portion where the toner T and the photoconductive layer 1c are separated, the toner T is predominantly acted on by the magnetic force generated by the magnetic roller 5a, and therefore does not adhere to the photosensitive drum 1.

On the other hand, as shown in FIG. 5, the photosensitive drum 1
When the LED corresponding to the writing signal is sequentially selected from the exposure device 7 to perform exposure at the portion C immediately before the toner T and the toner T are separated from each other, free carriers due to electronic excitation due to light absorption are generated in the photoconductive layer 1c. Is generated. This free career
The electric field acting in the photoconductive layer 1c neutralizes the charges injected into the photoconductive layer 1c by coming into contact with the toner T. Therefore, the surface potential of the photoconductive layer 1c is equal to that of the transparent conductive layer 1b.
And the potential difference is generated between the photoconductive layer 1c and the developing sleeve 5b.

After that, due to the potential difference as described above, the photoconductive layer 1c is passed again from the developing sleeve 5b through the toner T.
The charge is injected into the toner. However, since the photosensitive drum 1 and the developing sleeve 5b are separated from each other before the charge is sufficiently injected, the toner T is in a state where the charge is injected as shown in FIG. The magnetic roller 5a receives the action of the electric field acting between the developing sleeve 5b and the surface of the photosensitive drum 1 and the van der Waals force acting between the photosensitive drum 1 and the toner T.
The magnetic force of the above is shaken off to adhere to the surface of the photosensitive drum 1. As a result, a toner image corresponding to the write signal is formed on the surface of the photosensitive drum 1.

After the toner image is formed as described above and the photoconductor drum 1 passes through the contact area with the toner T, the neutralization device 27 is removed from the inside of the photoconductor drum 1 and the photoconductor drum 1 is removed.
By intermittently illuminating and exposing at a speed sufficiently higher than the moving speed of, the surface of the photosensitive drum 1 is discharged. The conditions for intermittently lighting the static eliminator 27 are as follows: peripheral speed v (mm / s) of the photosensitive drum 1, slit width a (mm) of the static eliminator 27, lighting time t ₁ (s),
If the extinguishing time is t ₂ (s), then t ₁ <a / v t ₂ = (a / v) −t ₁ . The condition of the exposure amount by the static eliminator 27 is W ₂ ≧ W ₁ when the exposure amount by the exposure device 7 is W ₁ and the exposure amount by the static eliminator 27 is W ₂ . That is, the static eliminator 27 is used with an exposure amount equal to or larger than the exposure amount of the exposure device 7.

Under the above conditions, for example, FIG.
As shown in FIG. 3, when the pulse signal A as shown in FIG. 3B is input to the transistor 29 to which the power source 28, the resistor R, and the static eliminator 27 are connected, for example, the pulse signal A for t ₁ seconds.
However, when it is at a high level, the transistor 29 is turned on, and a current flows through the static eliminator 27 to light. next,
When the pulse becomes Low level for t ₂ seconds after t ₁ seconds, the transistor 29 is turned off and the static eliminator 27 is discharged.
No current flows through the lamp and it goes out. By repeating such an operation, the static eliminator 27 is intermittently lit at a speed sufficiently higher than the moving speed of the photosensitive drum 1.

As described above, by exposing the photoconductor drum 1 while the static elimination device 27 is intermittently turned on, free carriers are generated in the photoconductive layer 1c of the photoconductor drum 1,
The charge on the photoconductor drum 1 is eliminated by neutralizing the charges injected into the photoconductive layer 1c by contact with the toner T.

As shown in FIG. 1, the toner image formed on the surface of the photosensitive drum 1 is applied to the transfer roller 9 by applying a voltage having a polarity opposite to the injected charge of the toner image, It is transferred onto the surface of the transfer / fixing belt 8 at the pressure contact portion between the photosensitive drum 1 and the transfer roller 9. Further, the toner remaining on the surface of the photosensitive drum 1 without being transferred is collected by the developing sleeve 5b. As shown in FIG. 7, in order to collect the toner T remaining on the photosensitive drum 1 after transferring the toner image on the photosensitive drum 1 to the transfer belt 8 by pressure contact with the transfer belt 8, The scraper 26 made of flexible rubber or the like may be provided above the toner carrier 5. By this scraper 26, the toner T remaining on the photosensitive drum 1 is collected again in the developing tank 3.

On the other hand, the transfer / fixing belt 8 on the heating device 10 and the pressure roller 12 are pressed against each other at the pressure contact portion.
The CPU (Central Processi) of the engine controller (not shown) is arranged so that the toner image on the surface and the transfer sheet P correspond to each other.
signal is output to the paper feed solenoid 20 from the (ng Unit), the above-mentioned rotation stop state of the registration rollers 19 and 19 is released, and the transfer paper P comes into contact with its leading end and the leading end of the transfer / fixing belt 8. Transfer at the timing that matches.
It is conveyed to the pressure contact portion between the fixing belt 8 and the pressure roller 12.

Then, a transfer / transfer of the above toner image is performed.
Since the fixing belt 8 and the transfer paper P are conveyed while being overlapped between the heating device 10 and the pressure roller 12,
The transfer and fixing of the toner image on the transfer paper P are simultaneously performed. That is, when the transfer paper P is sent out by being pressed against the transfer / fixing belt 8 and the pressure roller 12, the releasability of the toner T heated and melted by the heating device 10 is
Since the surface of the transfer / fixing belt 8 is better than the transfer paper P, most of the toner T on the surface of the transfer / fixing belt 8 is transferred / fixed onto the transfer paper P.

After that, the transfer paper P on which the above-mentioned toner image has been transferred and fixed is pushed up by the paper output actuator 23 and is discharged from the apparatus through the transfer paper discharge opening by the rotation of the conveying rollers 25. Then, after the transfer paper P is discharged to the outside of the apparatus and a predetermined time has elapsed, the heating device 10
When the heating resistor 10a is energized and the driving of the main motor 13 is stopped, the series of operations described above ends.

As described above, after the toner image is formed, the exposure device 7 is used to perform the exposure by the charge removing device 27 to remove the charge on the surface of the photoconductor drum 1 outside the contact area between the photoconductor drum 1 and the toner T. With the exposure amount equal to or more than the exposure amount, the static eliminator 27 is intermittently lit at a speed sufficiently higher than the moving speed of the photoconductor drum 1 so that, as in the conventional case,
It is possible to prevent the free carriers generated by the irradiation of the static elimination light from remaining on the surface of the photoconductor drum 1 as compared with the case where the exposure by the static eliminator 27 is continuously performed. Therefore, at the next charging of the photoconductor drum 1 due to the contact with the toner T held on the developing sleeve 5b, the charge due to the charging is not canceled by the free carrier, and the photoconductor drum 1 is sufficiently charged. It becomes possible. As a result, image fogging can be reduced.

Further, as described above, by using the static eliminator 27 with an exposure amount greater than that of the exposure device 7,
Since the static eliminator 27 is used in a stable light amount region, unevenness in the light amount due to the static eliminator 27 in the paper feeding direction in the image is also avoided, and unevenness of the surface potential of the photosensitive drum 1 can be reduced. As a result, the occurrence of afterimage can be reduced.

The present invention is not limited to the above embodiment, but various modifications can be made within the present invention. For example, in the above-described embodiment, an example in which the static eliminator 27 is intermittently turned on from the inside of the photoconductor drum 1 is shown. However, the static eliminator is provided outside the photoconductor drum and intermittently from the outside of the photoconductor drum. It is also possible to light it.

[Embodiment 2] Next, another embodiment of the present invention will be described below with reference to FIG.

In the electrophotographic apparatus of this embodiment, as shown in FIG. 8, a charging roller 32, an exposure device 33, a developing tank 35, a transfer roller 36, and a blade are provided around a photosensitive drum 31 having a photosensitive layer on the surface. 37, a waste toner box 38, and a static eliminator 40 are sequentially arranged. The developing tank 35 includes a magnet roller 34 that conveys a developer including a carrier and toner (not shown) to the photosensitive drum 31 side, and a stirring rod 39 that stirs the developer in the developing tank 35.
Is equipped with.

In the above structure, when a copying operation is performed, the charging roller 32 first causes the photosensitive drum 31 to move.
Are uniformly charged on the negative electrode side. Then, the exposure device 33 lights up in response to a write signal sent from a controller (not shown), so that a dot pattern of an electrostatic latent image is formed on the surface of the photosensitive drum 31. Next, in the developing tank 35, the toner and the toner are charged to the negative electrode side by stirring the carrier and the toner with the stirring rod 39, and a voltage lower than the surface potential of the photosensitive drum 31 by 100 V is applied to the magnet roller 34. Apply. As a result, the toner conveyed by the magnet roller 34 adheres to the portion of the photosensitive drum 31 where the surface potential is lowered,
A visible image is formed on the photosensitive drum 31.

Then, by transferring the transfer paper between the transfer roller 36 to which the positive voltage is applied and the photosensitive drum 31, the toner image formed on the photosensitive drum 31 is transferred onto the transfer paper. Transcribed. On the other hand, the toner remaining on the photoconductor drum 31 without being transferred to the transfer paper is the blade 3
It is scraped off by 7 and collected in the waste toner box. After that, the static eliminator 40 is intermittently turned on under the same conditions as in the first embodiment, and the surface of the photosensitive drum 31 is uniformly neutralized.

As described above, using the charging roller 32,
Even when the photoconductor drum 31 is charged, the first embodiment
As shown in FIG.
In the same manner as in the case of charging, the static elimination device 40 is intermittently turned on, so that it is possible to prevent the free carrier generated by the exposure by the static elimination device 40 from remaining on the photosensitive drum 31. At the time of the next charging by the charging roller 32, the free carriers do not cancel the charges, and the surface of the photosensitive drum 31 can be uniformly charged to a predetermined potential. As a result, image fogging can be reduced. In addition, since it is possible to turn on the static eliminator 40 in a stable light amount region, it is possible to reduce an afterimage without causing uneven light amount.

[0046]

As described above, the electrophotographic apparatus of the present invention is a static elimination light for intermittently lighting the static elimination light applied to the photoconductor by the static elimination means at a speed higher than the moving speed of the photoconductor. The control means is provided.

Therefore, the static elimination light emitted from the static elimination means to the photoconductor before the charging step is controlled by the static elimination light control means.
Even if the static eliminator is used in a stable light amount range, the free carriers generated by exposure remain on the photoconductor before the charging process by intermittently lighting at a speed faster than the moving speed of the photoconductor. It is possible to prevent the above, and it is possible to obtain the effect of reducing the fogging of the image.

Further, as described above, since the static eliminator can be used in a stable light quantity region, unevenness of the light quantity of the static eliminator is reduced and unevenness of the surface potential of the photoconductor is also reduced, so that an afterimage is caused. The effect that the fear of being avoided is also achieved.

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram showing various components constituting an electrophotographic apparatus according to an embodiment of the present invention.

FIG. 2 is a main part configuration diagram showing a photosensitive drum, a developing device, an exposure device, a charge eliminating device, and a dielectric belt in the electrophotographic apparatus.

3A is a circuit diagram showing a control method for intermittently lighting the static eliminator, and FIG. 3B is a waveform diagram showing a pulse signal given to the circuit of FIG. 3A.

FIG. 4 is an explanatory diagram showing a state where the surface of the photosensitive drum is charged by contact with toner T.

FIG. 5 is an explanatory diagram showing a state in which charges on the surface of the photosensitive drum are neutralized by exposure of an exposure device.

FIG. 6 is an explanatory diagram showing a state in which a toner image is formed on the surface of the photosensitive drum.

FIG. 7 is a main part configuration diagram showing another embodiment of the present invention.

FIG. 8 is a schematic configuration diagram showing still another embodiment of the present invention.

[Explanation of symbols]

 1.31 Photoreceptor drum (photoreceptor) 2 Developing device (developing means) 27.40 Static eliminator (static elimination means) 30 Static elimination light control means

Claims (1)

[Claims] 1. An electrophotographic apparatus for discharging the surface of a photoconductor by exposing the photoconductor from the end of the developing process by the developing device to the start of the next charging process by the charge removing device. An electrophotographic apparatus, comprising: static elimination light control means for intermittently turning on the static elimination light applied to the photoconductor by the means at a speed higher than the moving speed of the photoconductor.