JPH07191590A - Cleaning method of photoreceptor and electrophotographic copying machine - Google Patents

Abstract

PURPOSE:To provide the cleaning method of a photoreceptor not generating a failure in cleaning by sufficiently attenuating the potential by electrification of the photoreceptor charged by a transfer means and an electrophotographic copying machine not affecting the accuracy for receiving light of a photodetecting means with light emitted from a light irradiation means. CONSTITUTION:In the electrophotographic copying machine provided with the photoreceptor 1, a transfer means 3 having a transfer member 8 to which a transfer voltage is applied by a transfer electrifying means 4 having a voltage control means, a cleaning means 2 removing toner remaining on the photoreceptor 1 after a transfer process and the electrifying means 5 of the photoreceptor 1, a light irradiation means 6 is provided between the transfer means 3 and the cleaning means 2 and the photoreceptor 1 is irradiated with discharged light for attenuating the potential by the electrification made on the photoreceptor 1 by the transfer means 3, by the light irradiating means 6 to attenuate the potential by the electrification and then, cleaned by the cleaning means 2 to make the wavelength of the light emitted from the light irradiation means 6 different from that of the light received by the photodetecting means.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for cleaning a photoconductor of an electrophotographic copying machine and an electrophotographic copying machine.

[0002]

2. Description of the Related Art Conventionally, in a cleaning method of an electrophotographic copying machine and a photoconductor of this kind, the cleaning method of the photoconductor 1 is such that the toner electrostatically adhered to the photoconductor 1 after the transfer process is first. (1) The cleaning member 13 is loosened by mechanical rubbing, and at the same time, also has a charge eliminating function to eliminate the charge on the photoconductor 1 to reduce the cleaning load on the second cleaning member 14, and then the photoconductor 1 is cleaned. Those disclosed in JP-A-56-24382 are publicly known. As shown in FIG. 8, the cleaning means 2 provided on the downstream side of the transfer means 3 in the rotation direction of the photoconductor 1 is in contact with the photoconductor 1 under pressure.
And a second cleaning member 14 disposed behind the first cleaning member.
A conductive elastic roller 13 is used, a voltage having a polarity opposite to that of the ground or the electrostatic latent image is applied, and an elastic cleaning blade is used as the second cleaning member 14.

When the photosensitive member 1 is photo-electrified by the light irradiating means 6, the wavelength of the erasing light is irradiating with light of substantially the same color as the color of the toner to be developed in the last order to eliminate the electric charge, and the cleaning means 2 is used. A method for cleaning the photosensitive member 1 for cleaning is disclosed in Japanese Patent Laid-Open No. 307773/1993 and is publicly known. As shown in FIG. 9, the transfer means 3 transfers the color toner image obtained on the photoconductor 1 to the paper, and the transfer means 3 transfers the color toner image to the paper and then fixes the color toner image by heat fixing. A container 22, a cleaning means 2 for removing the color toner remaining on the photoconductor 1 after transfer, and a light irradiation means 6 for destaticizing the photoconductor 1 between the transfer means 3 and the cleaning means 2. is there. Figure 7,
In FIG. 8, 4 is a transfer charger, 5 is a charging unit, 8 is a transfer belt, and 9 is a developing unit.

[0003]

SUMMARY OF THE INVENTION In the conventional method for cleaning a photosensitive member, in which the charge is electrically eliminated before mechanically cleaning the photosensitive member as described above and in the prior art, the photosensitive member charged by the transfer means is charged. There is a problem that the electric potential cannot be sufficiently removed and cleaning failure of the photoconductor is likely to occur.

Therefore, an object of the present invention is to eliminate the above-mentioned problems of the conventional method for cleaning a photosensitive member, to sufficiently remove the charging potential of the photosensitive member charged by the transfer means, and to cause a cleaning failure. Another object of the present invention is to provide a method for cleaning a photoreceptor, and an electrophotographic copying machine in which the emitted light of the light irradiation means for eliminating the charge potential of the photoreceptor does not deteriorate the detection accuracy of the light detection means provided in the vicinity thereof.

[0005]

In order to achieve the above-mentioned object, the invention of claim 1 applies a transfer potential by a photoconductor and a transfer charging means having a voltage control means. A transfer unit having a belt- or roller-shaped transfer member, a cleaning unit that removes toner remaining on the photoconductor after the transfer process, and a charging unit that charges the photoconductor to form an electrostatic latent image. In the electrophotographic copying machine, a light irradiating unit is provided between the transfer unit and the cleaning unit, and the light irradiating unit irradiates the charge removing light for attenuating the charging potential generated on the photoconductor by the transfer unit to the photoconductor. After the charging potential of (1) is attenuated, the photosensitive member is cleaned by the cleaning means. According to a second aspect of the present invention, a photoconductor, a transfer unit including a belt- or roller-shaped transfer member to which a transfer potential is applied by a transfer charging unit having a voltage control unit, and the transfer unit remains on the photoconductor after the transfer process. In an electrophotographic copying machine including a cleaning unit for removing toner and a charging unit for charging a photoconductor to form an electrostatic latent image, the transfer potential control unit is charged by the transfer member with a current flowing through the transfer member. The charging potential of the photosensitive member is limited to a charging potential or less charged by the charging unit during image formation, a voltage is applied to the transfer member, and the photosensitive member is cleaned by the cleaning unit after the transfer step. Is. According to a third aspect of the present invention, there is provided a photoconductor, a transfer unit including a belt- or roller-shaped transfer member to which a transfer potential is applied by a transfer charging unit having a voltage control unit, and the transfer unit remains on the photoconductor after the transfer process. An electrophotographic copying machine comprising: a cleaning unit for removing toner, a charging unit for charging a photosensitive member to form an electrostatic latent image, and a developing unit for developing a latent image formed on the photosensitive member with a toner. , A surface potential detecting means for detecting the surface potential of the photoconductor is provided between a portion of the exposure point for forming a latent image on the photoconductor and the developing means, and the photoconductor is operated while the operation of the charging means is stopped. The photoconductor is rotated to charge the photoconductor by the transfer member, and the charged potential is detected by the surface potential detection means and output to the voltage control means, which voltage control means is within a preset range for the transfer member. Voltage to Correct by applying, after the transfer step,
It is characterized in that the photosensitive member is cleaned by the cleaning means. According to a fourth aspect of the present invention, a photoconductor, a transfer unit including a belt- or roller-shaped transfer member to which a transfer potential is applied by a transfer charging unit having a voltage control unit, and the transfer unit remains on the photoconductor after the transfer process. In an electrophotographic copying machine having a cleaning means for removing toner and a charging means for charging a photoconductor to form an electrostatic latent image, the cleaning means has a conductive fur brush that rotates. A potential applying means for applying a potential to the brush is provided, and when the conductive fur brush comes into contact with the photoconductor, the potential applying means prevents the discharge of the transfer potential between the conductive fur brush and the photoconductor. Voltage is applied to the conductive fur brush in accordance with the above, the photosensitive member is rubbed by the conductive fur brush, and the photosensitive member is cleaned by the cleaning means. And it is characterized in and. According to a fifth aspect of the present invention, there is provided a photoconductor, a transfer unit including a belt- or roller-shaped transfer member to which a transfer potential is applied by a transfer charging unit having a voltage control unit,
After the transfer step, in an electrophotographic copying machine equipped with a cleaning means for removing the toner remaining on the photoconductor and a charging means for charging the photoconductor to form an electrostatic latent image, the cleaning means rotates the conductive material. Have a fur brush,
A conductive member electrically provided on the upstream side in the rotation direction of the conductive fur brush at the portion where the photoconductor and the conductive fur brush come into contact is provided in contact with the conductive fur brush, and the conductive fur brush is provided. Before contacting the photoconductor, the conductive fur brush contacts the conductive member to discharge the charging potential of the conductive fur brush, and the conductive fur brush rubs the photoconductor to remove the charge. It is characterized in that the photoconductor is cleaned. According to a sixth aspect of the present invention, there is provided a photoconductor, a transfer unit including a belt- or roller-shaped transfer member to which a transfer potential is applied by a transfer charging unit having a voltage control unit, and the transfer unit remains on the photoconductor after the transfer process. In an electrophotographic copying machine including a cleaning unit that removes toner, a charging unit that charges a photosensitive member to form an electrostatic latent image, and a toner supply control unit, between the transfer unit and the cleaning unit. In addition to providing the light irradiation means, the reflected light of the toner image formed on the photoconductor is detected and output, and the output is input to the toner supply control means to set the toner concentration and the replenishment amount of the developer to predetermined amounts. A light detecting means for maintaining the light is provided in the vicinity of the light irradiating means, and the light irradiating means irradiates a discharging light for attenuating the charge potential generated on the photoconductor by the transfer means to attenuate the charge potential of the photoconductor. Peak wavelength of the emission energy the light irradiating means for cleaning the photosensitive member by Ningu means emits light, detection sensitivity energy of said light detecting means is characterized in that different from the wavelength of maximum.

[0006]

In this invention as described above, the invention of claim 1 irradiates the photosensitive member with a discharging light for attenuating the charging potential of the photosensitive member by the light irradiation means provided between the transfer means and the cleaning means. After the transfer means attenuates the charging potential generated on the photoconductor, the cleaning means cleans the photoconductor. According to a second aspect of the present invention, the voltage control means limits the voltage applied to the transfer member to a value equal to or less than the charge potential charged by the charging means at the time of image formation by the current flowing through the transfer member so that the charging potential of the photoconductor is charged. Is applied, and the photoconductor is cleaned by a cleaning means after the transfer step. According to a third aspect of the present invention, a surface potential detecting means for detecting the surface potential of the photosensitive member is provided between the exposure point portion for forming a latent image on the photosensitive member and the developing means, and the charging means operates. The photosensitive member is rotated by the transfer member while being stopped, the photosensitive member is charged by the transfer member, and the charged potential is detected and output by the surface potential detecting means and input to the voltage control means. The voltage is corrected and applied to the member within a preset range, and after the transfer step, the photosensitive member is cleaned by the cleaning unit. According to a fourth aspect of the present invention, the cleaning means has a rotating conductive fur brush, and the potential applying means for applying a potential to the conductive fur brush is provided, and the conductive fur brush contacts the photoconductor. At the time of contact, the potential applying means changes the voltage corresponding to the transfer potential and applies it to the conductive fur brush so that no discharge occurs between the conductive fur brush and the photosensitive body. The discharge is prevented between the fur brush and the conductive fur brush, and the photosensitive member is rubbed by the conductive fur brush without adhering the toner to the conductive fur brush, and the photosensitive member is cleaned by the cleaning unit. According to a fifth aspect of the present invention, the cleaning unit has a rotating conductive fur brush, and is electrically installed on the upstream side of the rotating direction of the conductive fur brush at the portion where the photoconductor and the conductive fur brush come into contact with each other. The electrically conductive fur brush is provided in contact with the electrically conductive fur brush, and the electrically conductive member discharges the charging potential of the electrically conductive fur brush before the electrically conductive fur brush rotates and comes into contact with the photoconductor. At the same time, the photoconductor is rubbed, and the photoconductor is cleaned by the cleaning means. According to a sixth aspect of the present invention, a light irradiation unit is provided between the transfer unit and the cleaning unit, and the reflected light of the toner image formed on the photoconductor is detected and output, and the output is the toner supply control unit. Is provided in the vicinity of the light irradiating means for maintaining the toner concentration and the replenishment amount of the developer at a predetermined amount, and the light irradiating means is used to remove the charge eliminating light to the photoreceptor. After the irradiation, the charging potential of the photoconductor is attenuated, and then the peak wavelength of the light emission energy emitted by the light irradiation unit for cleaning the photoconductor by the cleaning unit generated on the photoconductor by the transfer unit is detected by the light detection unit. Even if the light of the light irradiation means is incident on the light detection means, the detection accuracy of the light detection means is not affected even if the light of the light irradiation means has a wavelength different from the maximum sensitivity energy.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS In the electrophotographic copying machine embodying the present invention, the same parts as those of the conventional one will be designated by the same reference numerals, and the description thereof will be omitted.

The first embodiment shown in FIG. 1 includes a transfer means 3 and
A light irradiation unit 6 (hereinafter referred to as PCL) having a charge eliminating lamp for removing the charging potential of the photoconductor 1 is provided between the cleaning unit 2 and the transfer unit 3, and the transfer unit 3 is a belt or roller transfer member 8 and the transfer member 8 thereof. And a transfer charging means 4 having a voltage control means 18 having a calculation means (not shown) for applying a transfer potential. Reference numeral 9 is a developing means, 30 is a discharge lamp after cleaning, 31 is a cleaning blade, and 32 is a toner carrying coil.

In such a structure, after the transfer step, the photoconductor 1 is irradiated with light at a level at which the charging potential of the photoconductor 1 is attenuated by the PCL 6, and then the photoconductor 1 is cleaned by the cleaning means 2. . That is, the charging potential of the photoconductor 1 has risen as shown in FIG. 2 after the transfer process, and when the PCL 6 is not provided, the paper is fed in the B5 portrait mode, and the transfer current applied to the transfer member 8 is −80 μA. If
A defective cleaning image is generated on the copy image. On the other hand, when the PCL 6 irradiates light, the charging potential of the photoconductor 1 can be attenuated even if the transfer current is −100 μA, and the defective cleaning does not occur. However, even when light irradiation is performed, the charging potential of the photoconductor 1 that has received the light irradiation of the PCL 6 is cleaned by performing light irradiation at an energy level such that the absolute value thereof is lower than 600 V as shown in FIG. Since no bad image occurs,
It is sufficient that the light irradiation energy level has the same energy level as the exposure intensity for image formation, and does not affect the light fatigue of the photoconductor 1.

In the above-mentioned embodiment, if the PCL is not provided, the transfer voltage is applied to the transfer member by the voltage control means, and the transfer current flowing according to the transfer potential value at that time, that is, the transfer potential is proportional to the transfer current. The transfer member is charged by limiting the transfer current, and the photosensitive member 1 is cleaned without causing cleaning failure in the cleaning performed after the transfer process. It limits the transfer current flowing through the transfer member so that when the transfer member is brought into contact with the photoconductor, it becomes equal to or lower than the charging potential of the photoconductor given by the charging means during normal image formation. The maximum upper limit value is set to -150 μA, which can be switched depending on the transfer paper size. As the transfer paper has a narrower width, the current easily flows toward the photoconductor, so that the transfer current upper limit value is set corresponding to each transfer paper size. The width of the transfer paper is narrower than that of the wide paper, and it is set to be -60 μA for B5 vertical paper size and -80 μA for A4 horizontal paper size. After selecting and applying to the transfer member 8, the photoconductor 1 is cleaned after the transfer process.

In the second embodiment shown in FIG. 3, a surface potential detecting means 16 having a potential sensor is provided with an exposing portion 15 for forming a latent image on the photoconductor 1 and a developing means 9 for developing the latent image with toner. It is provided between them. Before starting the image forming operation, the operation of the charging means 5 for charging the photoconductor 1 to form a latent image is stopped, the photoconductor 1 is rotated, and two levels of the transfer current, that is, −20 μA, Then −100 μA
Are applied to the transfer member 8 to charge the photoconductor 1, and the charging potential of the photoconductor 1 by them is detected by the surface potential detection means 16 and output, and the output and the paper size signal are controlled by the voltage control means 18. Is input to a calculation unit (not shown) to perform a calculation process for correcting a variation in the charging potential of the photoconductor 1 due to a transfer member difference, a mechanical difference, a photoconductor difference, and the like, and the paper size.
As for the transfer current, as shown in FIG.
After correction so as to give 600 V in the vertical direction and 400 V in the A4 horizontal direction, the image forming operation is executed, and the photoconductor 1 is cleaned after the transfer step. As a result, the cleaning of the photoconductor 1 can be made more reliable.

In the second embodiment, in which the conductive fur brush is used as the cleaning means, the bias voltage is applied to the conductive fur brush so that the discharge phenomenon does not occur due to the potential difference between the conductive fur brush and the photosensitive member. It is applied by a voltage applying means. As shown in FIGS. 2 and 6, the absolute value is 400 V or less under the condition that the discharge phenomenon due to the potential difference between the conductive fur brush and the photosensitive member does not occur. Apply to clean the photoreceptor.

The cleaning means 2 in the second embodiment is as shown in FIGS.
Is the static elimination brush 11 shown in FIG. 4 or the static elimination wire shown in FIG. 5 before the conductive fur brush 10 contacts the photoconductor 1.
Twelve are provided. These discharging means are electrically installed, thereby discharging the charge of the conductive fur brush 10, and the static elimination brush 11 or the static elimination wire 12 is always the conductive fur brush 10 whose toner is removed by flicker. The cleaning performance is maintained by being cleaned, and the electroconductive fur brush 10 rubs the photoreceptor 1 for cleaning.

In the third embodiment shown in FIG. 7, the transfer means 3 has a belt- or roller-shaped transfer member 8 and a voltage control means 18 having a calculation means (not shown) for applying a transfer potential to the transfer member 8. Transfer charging means 4 and transfer means 3
And a cleaning means 2 are provided with a PCL 6 having a discharge lamp for removing the charging potential of the photoconductor 1.
A light detecting means 7 having a light detecting sensor (hereinafter referred to as a P sensor) is provided in the vicinity of L6. This P sensor 7
Has an optical sensor (not shown) for detecting the developing ability of the toner image formed on the photoconductor 1 by detecting reflected light.
When cleaning the photoconductor 1 by attenuating the charging potential of the photoconductor 1 by the light irradiation of CL6, even if the light of the PCL6 enters the P sensor 7, it does not affect the detection accuracy of the P sensor 7. And the peak wavelength of the light emission of the PCL6 and the peak wavelength of the light receiving sensitivity of the P sensor 7 are different, and those wavelengths are such that the light emission peak wavelength of the PCL6 is 600 to 700 nm (red light), P The peak wavelength of the light receiving sensitivity of the sensor 7 is 900 to 950 nm (infrared light). Reference numeral 9 is a developing means, 30 is a discharge lamp after cleaning, 31 is a cleaning blade, and 32 is a toner carrying coil.

[0015]

The present invention is as described above, and the invention of claim 1 provides a belt-shaped or roller-shaped transfer member to which a transfer potential is applied by a transfer charging unit having a voltage control unit. An electrophotographic copying machine comprising: a transfer unit, a cleaning unit that removes toner remaining on the photoconductor after the transfer process, and a charging unit that charges the photoconductor to form an electrostatic latent image. After the light irradiating means is provided between the transfer means and the cleaning means, the light irradiating means irradiates the charge removing potential for attenuating the charge potential generated on the photoconductor by the transfer means to attenuate the charge potential of the photoconductor. Since the photosensitive member is cleaned by the cleaning unit, the charging potential of the photosensitive member charged by the transfer unit can be sufficiently removed, and the cleaning failure does not occur. According to a second aspect of the present invention, a photoconductor, a transfer unit including a belt- or roller-shaped transfer member to which a transfer potential is applied by a transfer charging unit having a voltage control unit, and the transfer unit remains on the photoconductor after the transfer process. In an electrophotographic copying machine including a cleaning unit for removing toner and a charging unit for charging a photoconductor to form an electrostatic latent image, the voltage control unit is charged by the transfer member with a current flowing through the transfer member. The charging potential of the photosensitive member is limited so as to be equal to or lower than the charging potential charged by the charging unit during image formation, and a voltage is applied to the transfer member, and the photosensitive member is cleaned by the cleaning unit after the transfer step. There is an effect that excessive charging of the body can be prevented and defective cleaning can be prevented. According to a third aspect of the present invention, there is provided a photoconductor, a transfer unit including a belt- or roller-shaped transfer member to which a transfer potential is applied by a transfer charging unit having a voltage control unit, and the transfer unit remains on the photoconductor after the transfer process. An electrophotographic copying machine comprising: a cleaning unit for removing toner, a charging unit for charging a photosensitive member to form an electrostatic latent image, and a developing unit for developing a latent image formed on the photosensitive member with a toner. , A surface potential detecting means for detecting the surface potential of the photoconductor is provided between a portion of the exposure point for forming a latent image on the photoconductor and the developing means, and the photoconductor is operated while the operation of the charging means is stopped. The photoconductor is rotated to charge the photoconductor by the transfer member, and the charged potential is detected by the surface potential detection means and output to the voltage control means, which voltage control means is within a preset range for the transfer member. Voltage to After the transfer step is applied to correct, because cleaning the photosensitive member of the photosensitive member by a cleaning means, there is an effect that since the excessive charging of the photosensitive member can be prevented can be reliably prevented poor cleaning. According to a fourth aspect of the present invention, a photoconductor, a transfer unit including a belt- or roller-shaped transfer member to which a transfer potential is applied by a transfer charging unit having a voltage control unit, and the transfer unit remains on the photoconductor after the transfer process. In an electrophotographic copying machine having a cleaning means for removing toner and a charging means for charging a photoconductor to form an electrostatic latent image, the cleaning means has a conductive brush that rotates, and the conductive brush is A potential applying means for applying a potential is provided, and when the conductive brush comes into contact with the photoconductor, the potential applying means responds to the transfer potential so that no discharge occurs between the conductive brush and the photoconductor. The voltage is changed and applied to the conductive brush, and the photosensitive member is rubbed by the conductive brush, and the cleaning unit cleans the photosensitive member. If any time prevents discharge between the photosensitive member and the conductive brush, the toner is not reduced toner removal effect of the conductive brush without charge, there is an effect that generates no cleaning failure. According to a fifth aspect of the present invention, the photoconductor, the transfer means having a belt or roller-shaped transfer member to which a transfer electric potential is applied by the transfer charging means having the voltage control means, and the transfer means remaining on the photoconductor after the transfer step. In an electrophotographic copying machine having a cleaning means for removing toner and a charging means for charging a photoconductor to form an electrostatic latent image, the cleaning means has a conductive brush that rotates.
A conductive member that is electrically grounded is provided in contact with the conductive brush on the upstream side in the rotation direction of the conductive brush at the portion where the photosensitive member and the conductive brush come into contact, and the conductive brush is attached to the photosensitive member. Before contacting, the charging potential of the conductive brush is discharged by the conductive member and the photoconductor is rubbed,
Since the cleaning means cleans the photoconductor, the conductive brush is neutralized, so that even if the charge potential is high in the transfer step of the photoconductor, the charge potential is neutralized, and there is no effect that a cleaning failure does not occur. is there. According to a sixth aspect of the present invention, there is provided a photoconductor, a transfer unit including a belt- or roller-shaped transfer member to which a transfer electric potential is applied by a transfer charging unit having a voltage control unit, and the transfer unit remains on the photoconductor after the transfer process. In an electrophotographic copying machine including a cleaning unit that removes toner, a charging unit that charges a photosensitive member to form an electrostatic latent image, and a toner supply control unit, between the transfer unit and the cleaning unit. A light irradiation unit is provided, and the reflected light of the toner image formed on the photoconductor is detected and output, and the output is input to the toner supply control unit to set the toner concentration and the replenishment amount of the developer to predetermined amounts. A light detecting means for maintaining the light is provided in the vicinity of the light irradiating means, and the light irradiating means irradiates the charge removing light for attenuating the charging potential generated on the photoreceptor by the transfer means to attenuate the charging potential of the photoreceptor, Since the peak wavelength of the light emission energy emitted by the light irradiation means for cleaning the photoconductor by the burning means is different from the wavelength at which the detection sensitivity energy of the light detection means becomes maximum, the light detection means may be erroneous due to the light emission of the light irradiation means. There is an effect that the detection accuracy is high without performing the detection.

[Brief description of drawings]

FIG. 1 is a schematic vertical sectional view of a first embodiment of the present invention.

FIG. 2 is a characteristic diagram showing a relationship between a transfer current, a cleaning grandk and a photoconductor charging potential, which are the same as the above.

FIG. 3 is a schematic vertical sectional view of a second embodiment of the above.

FIG. 4 is a schematic vertical sectional view showing a portion of the cleaning means of the second embodiment of the above.

FIG. 5 is a schematic vertical sectional view showing a portion of another cleaning means of the second embodiment.

FIG. 6 is a characteristic diagram showing the relationship between the conductive fur brush current and the transfer current in the above.

FIG. 7 is a schematic vertical sectional view of a third embodiment of the above.

FIG. 8 is a schematic vertical sectional view of a conventional electrophotographic copying machine.

FIG. 9 is a schematic vertical sectional view of another electrophotographic copying machine of the above.

[Explanation of symbols]

 1 Photoreceptor 2 Cleaning Means 3 Transfer Means 4 Transfer Charging Means 5 Charging Means 6 Light Irradiating Means 7 Light Receiving Means 8 Transfer Member 10 Conductive Fur Brush 11 Eliminating Brush 12 Wire 16 Surface Potential Detecting Means

Continuation of front page (51) Int.Cl. ⁶ Identification number Office reference number FI Technical display location G03G 21/08 G03G 21/00 340 342 (72) Inventor Sadao Takahashi 1-3-6 Nakamagome, Ota-ku, Tokyo No. Stock Company Ricoh

Claims (6)

[Claims] 1. A transfer member comprising a photosensitive member, a belt- or roller-shaped transfer member to which a transfer electric potential is applied by a transfer charging unit having a voltage control unit, and toner remaining on the photosensitive member after the transfer step. In an electrophotographic copying machine having a cleaning means for removing and a charging means for charging a photoconductor to form an electrostatic latent image, a light irradiation means is provided between the transfer means and the cleaning means. Cleaning of the photoconductor, characterized in that the irradiation unit irradiates the charge potential of the photoconductor on the photoconductor by the transfer unit to attenuate the charge potential of the photoconductor and then the cleaning unit cleans the photoconductor. Method. 2. A transfer member comprising a photosensitive member, a belt- or roller-shaped transfer member to which a transfer electric potential is applied by a transfer charging unit having a voltage control unit, and toner remaining on the photosensitive member after the transfer step. In an electrophotographic copying machine comprising cleaning means for removing and charging means for charging the photoconductor to form an electrostatic latent image, the voltage control means comprises:
The charge potential of the photoconductor charged by the transfer member by the current flowing in the transfer member is limited to the charge potential charged by the charging unit or less at the time of image formation to apply a voltage to the transfer member, and after the transfer process, the cleaning unit A method for cleaning a photoconductor, which comprises cleaning the photoconductor with. 3. A transfer member comprising a photosensitive member, a belt or roller-shaped transfer member to which a transfer potential is applied by a transfer charging unit having a voltage control unit, and toner remaining on the photosensitive member after the transfer step. Cleaning means for removing, charging means for charging the photoreceptor to form an electrostatic latent image,
In an electrophotographic copying machine equipped with a developing means for developing a latent image formed on a photosensitive member with a toner, a photosensitive member is provided between a portion of an exposure point for forming a latent image on the photosensitive member and the developing means. Surface potential detecting means for detecting the surface potential is provided, the photosensitive member is rotated while the operation of the charging means is stopped and the photosensitive member is charged by the transfer member, and the charged potential is detected by the surface potential detecting means and output. Then, the voltage control means corrects and applies the voltage to the transfer member within a preset range, and the cleaning means cleans the photoconductor after the transfer step. How to clean the photoreceptor. 4. A transfer member comprising a photosensitive member, a belt- or roller-shaped transfer member to which a transfer potential is applied by a transfer charging unit having a voltage control unit, and toner remaining on the photosensitive member after the transfer step. In an electrophotographic copying machine having a cleaning means for removing and a charging means for charging a photoconductor to form an electrostatic latent image, the cleaning means has a rotating conductive fur brush. An electric potential applying means for applying an electric potential is provided, and when the conductive fur brush comes into contact with the photoconductor, the electric potential applying means responds to the transfer electric potential so as not to generate discharge between the conductive fur brush and the photoconductor. Then, the voltage is changed and applied to the conductive fur brush. The conductive fur brush rubs the photosensitive member, and the cleaning unit cleans the photosensitive member. A characteristic method for cleaning a photoconductor. 5. A transfer member comprising a photosensitive member, a belt- or roller-shaped transfer member to which a transfer potential is applied by a transfer charging unit having a voltage control unit, and toner remaining on the photosensitive member after the transfer step. In an electrophotographic copying machine having a cleaning means for removing and a charging means for charging the photoconductor to form an electrostatic latent image, the cleaning means has a conductive fur brush, and the photoconductor and the conductive fur brush are rotated. A conductive member, which is electrically grounded, is provided in contact with the conductive fur brush on the upstream side in the rotation direction of the conductive fur brush at the portion in contact with the brush, and the conductive fur brush contacts the photoconductor. Before, the charging potential of the conductive fur brush is discharged by the conductive member, the photosensitive member is rubbed, and the photosensitive member is cleaned by a cleaning unit. How to clean the photoreceptor. 6. A transfer member comprising a photosensitive member, a belt- or roller-shaped transfer member to which a transfer electric potential is applied by a transfer charging unit having a voltage control unit, and toner remaining on the photosensitive member after the transfer step. Cleaning means for removing, charging means for charging the photoreceptor to form an electrostatic latent image,
In an electrophotographic copying machine including a toner supply unit, a light irradiation unit is provided between the transfer unit and the cleaning unit, and the reflected light of the toner image formed on the photoconductor is detected and output. A light detection unit for inputting the output to the toner supply control unit to maintain the toner concentration and the replenishment amount of the developer at a predetermined amount is provided in the vicinity of the light irradiation unit, and the light irradiation unit causes the transfer unit to generate on the photoconductor. The peak wavelength of the emission energy emitted by the light irradiating means for cleaning the photoconductor by the cleaning means after irradiating the charge eliminating light for attenuating the charge potential to attenuate the charge potential of the photoreceptor is detected by the light detecting means. An electrophotographic copying machine characterized in that the sensitivity energy is different from the maximum wavelength.