JPH07191588A - Cleaning method and device for image forming device - Google Patents

Abstract

PURPOSE:To provide a cleaning method and device maintaining cleaning performance over a long period of time without the occurrence of flaws and a stress on an image information forming body and being effective in the prolongation of the image information forming body and coloring as well and applicable to a high-speed machine and a large-scaled machine as well without requiring a mechanism letting a cleaning member contact/uncontact. CONSTITUTION:A fluid viscous flow generated by a fluid viscous flow generating member 2 disposed with a gap with respect to the image information forming body 1 is led to the gap 3, the depositions of the toner, etc, stuck to the surface of the image information forming body 1 is removed and the depositions after the removal is recovered by a recovering/carrying member 4. Further, a bias voltage by only a DC voltage, the vibrating voltage of only an alternating current, the vibrating voltage obtained by superimposing the alternating current on a direct current, etc., are applied to the gap 3.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image forming apparatus used in a field using an electrophotographic system such as a copying machine, a laser printer, a facsimile, etc., and an electronic latent image formed on an image information forming body by toner or the like. The present invention relates to a cleaning method and apparatus for an image forming apparatus that removes adhering substances such as toner remaining on the surface of an image information forming body after development and transfer to a transfer body.

[0002]

2. Description of the Related Art FIG. 10 shows a conventional electrophotographic image forming apparatus. An electrostatic latent image, a charge latent image, a conductive latent image, or other electronic latent image formed on the surface of the image information forming body 1 is visualized by developing a developer 18 which is charged fine particles colored with carbon black or the like. It is a process of forming a toner latent image on the surface of the body 1, transferring the toner latent image to a transfer body 14 such as paper, and then fixing it. In this process, in the transfer process of transferring the toner latent image to the transfer body, the transfer is not completed completely, and about 20% of the toner latent image remains on the image information forming body. This residual toner latent image is called residual toner 6. The remaining toner 6 affects the subsequent processes such as charging and exposure of the image information forming body 1 and remarkably deteriorates image quality such as fog, resolution and solid black density. As a method (cleaning method) for removing the residual toner 6 from the image information forming body, a cleaning method in which a cleaning member such as a cleaning blade, a magnetic brush, a fur brush, or a cleaning roller is brought into contact with or in contact with the image information forming body is often used. Has been. Among these methods, there is a method using a cleaning blade having a simple configuration and relatively good cleaning performance. In a cleaning device of an image forming apparatus using this method, a cleaning member is an image information forming member. It is in contact with and comes into contact with, and the image quality is apt to deteriorate due to scratches and filming on the surface of the image information forming body due to foreign matter being caught, etc., which has a drawback in terms of life and maintenance. .

Further, the toner, which is a colored particle, has a small particle size,
In the case of spheroidizing, the toner rubs off and the sufficient cleaning performance is not exhibited, and it is very difficult to remove the toner, and in consideration of colorization, the contact with a method other than the method using a cleaning blade Since they are in contact with each other, a mechanism for bringing the cleaning member into and out of contact with the cleaning device is required.

As a cleaning device which solves the above-mentioned drawbacks, Japanese Patent Publication Nos. 5-17552 and 5-23436.
As disclosed in, cleaning using an air suction method in which non-contact suction of residual toner is performed at an air suction port close to the peripheral surface of the photosensitive drum or an air blowing method in which non-contact blows residual toner away at the air outlet. There is a device. But,
The former method requires a relatively large suction means for sucking the toner, causes a decrease in suction force due to clogging of the suction port when the cleaning device is continuously used, and further sucks the toner. Maintenance such as replacement of the filter to efficiently separate the toner from the air is also necessary, and in the latter method it is necessary to separately provide a blower device for sending the air blown onto the toner, and to guide the air mixed with the toner. It is necessary to keep the blades in contact with each other and also to perform maintenance such as replacement of a filter for efficiently separating the toner from the discharged air.

[0005]

In the conventional cleaning method and apparatus, any of those using a brush or a blade comes into contact with or abuts against the surface of the image information forming body and rubs against it, so that the surface is easily scratched and the life is shortened. However, there are problems such as shortening of image quality and deterioration of image quality. In addition, the method using a cleaning blade has a problem that filming of toner, talc, or the like is likely to occur.

As a method of not contacting or abutting, there are an air suction method and an air blowing method for removing toner and the like in a non-contact manner, but a cleaning device using these methods requires a suction device, a blowing device and a filter. However, there is a problem that the suction port and the like are clogged, and the cleaning device tends to be large.

In view of the above-mentioned problems, the present invention cleans the image information forming body in a non-contact manner while keeping a small gap, and the image information forming body is free from scratches and the like. It maintains cleaning performance for a long period of time, and is also effective for extending the life of the image information forming body and coloring it, and does not require a device for separating and contacting the cleaning member,
An object of the present invention is to provide an image forming apparatus cleaning method and apparatus applicable to high speed machines and large machines.

[0008]

According to the present invention, there is provided a fluid viscous flow generating member, which is disposed in the vicinity of an image information forming body with a slight gap maintained with respect to the image information forming body. Rotate about an axis perpendicular to the axis perpendicular to the surface of the green body. Further, a cleaning unit is provided for removing adhered matters such as toner on the image information forming body by the fluid viscous flow generated by the rotation of the fluid viscous flow generating member itself. And, further, the fluid viscous flow is guided to the gap, and the adhered matters such as the toner adhered on the image information forming body are removed,
The present invention is characterized by having a sea-boat transporting means for collecting the adhered substances such as the toner after the removal by the collecting and transporting member.

Further, according to the present invention, the recovery / transport member of the recovery / transport means is made of a non-insulating material. Then, the adhered substances such as the toner after the removal are removed by the recovery bias applying means.
It is characterized in that the collecting and conveying member of the collecting and conveying means applies a collecting bias voltage to the gap between the image information forming body and the collecting and conveying member.

Further, according to the present invention, the fluid viscous flow generating member of the cleaning means is made of a non-insulating material, and the auxiliary bias voltage by the DC bias voltage is applied to the gap between the cleaning means and the image information forming body by the auxiliary bias applying means. The auxiliary bias applying means is provided so as to apply the voltage.

Further, according to the present invention, in the gap between the fluid viscous flow generating member of the cleaning means and the image information forming body, the auxiliary bias applying means converts the oscillating voltage of only the alternating bias voltage or the alternating bias voltage into the alternating bias voltage. It is characterized in that the auxiliary bias applying means is provided so as to apply an auxiliary bias voltage by an oscillating voltage superposed with.

Further, according to the present invention, the frequency of the alternating bias voltage of the alternating bias voltage by the auxiliary bias applying means or the alternating bias voltage of the oscillating voltage obtained by superposing the alternating bias voltage on the direct bias voltage is 500 Hz to 10 kHz.
z, and an auxiliary bias applying means for applying an auxiliary bias voltage for applying a peak-to-peak voltage of 500 V to 5 kVp-p.

Further, according to the present invention, the frequency of the alternating bias voltage of only the alternating bias voltage by the auxiliary bias applying means or the alternating bias voltage of the oscillating voltage obtained by superimposing the alternating bias voltage on the direct bias voltage is 1.5 kHz to 5 kHz.
z, and an auxiliary bias applying means for applying an auxiliary bias voltage for applying a peak-to-peak voltage of 1 kV to 4 kVp-p.

Further, the viscous fluid flow generating member of the cleaning means is made of insulating rubber, plastic material,
It is characterized by being a material insulating material composed of a high molecular weight organic material such as a porous material or a foaming material.

Further, the viscous fluid flow generating member of the cleaning means is made of a conductive or semi-conductive polymer organic material containing a conductive material such as carbon, aluminum, copper, steel and their alloy materials. It is characterized by being a non-insulating material such as a conductive metal material.

Further, in the above-mentioned constitution, at least one of a discharging means for making the specific charge of the toner uniform and a discharging means for removing the residual charge of the image information forming body is provided on the upstream side of the cleaning means. .

The viscous fluid flow generating member of the cleaning means is made of an insulating or non-insulating material.
As long as it is a non-insulating material, a conductive metal material such as aluminum, copper, steel and their alloy materials, a conductive or semi-conductive polymer organic material containing a conductive material such as carbon, etc. Is. Examples of the insulating material include rubber having an insulating property, a plastic material, a porous material, and a foaming polymer organic material.

The recovery / conveyance member of the recovery / conveyance means applies a recovery bias voltage, and therefore is made of a conductive or semi-conductive material containing a conductive material such as aluminum, copper and their alloy materials, carbon. Composed of non-insulating material.

The recovery bias applying means and the auxiliary bias applying means are high-voltage power supply devices, and can output an oscillating voltage based on a DC bias voltage of both positive and negative polarities, an AC bias voltage of an arbitrary waveform, or an oscillating voltage obtained by superposing them.

[0020]

When cleaning is performed using the above-described cleaning device, the viscous fluid flow generating member of the cleaning means rotates about an axis perpendicular to the axis perpendicular to the surface of the image information forming body, whereby the image information forming There will be a velocity difference between the two wall surfaces of the body and the viscous fluid flow generating member.
A fluid viscous flow is generated by viscous action of air represented by Newton's law of viscosity due to this velocity difference.

The fluid viscous flow generated by the rotation of the fluid viscous flow generating member itself of the cleaning means is introduced into the gap between the image information forming body and the fluid viscous flow generating member. And
For adhered substances such as toner adhered to the surface of the image information forming body,
A shear force is applied by the fluid viscous flow. By making the shearing force larger than the adhesive force of the adhered matter such as toner with the image information forming body, the adhered matter such as the toner is peeled off from the surface of the image information forming body and removed from the image information forming body,
Cleaning is performed.

If the velocity difference between the two wall faces, that is, the velocity gradient between the two wall faces is large, the shear stress applied to the adhered material such as toner is large.

The adhered substances such as the toner after the removal are electrostatically collected by the collecting and conveying member to which the collecting bias applying means applies the collecting bias voltage having the polarity opposite to the polarity of the toner and the like.

Further, the auxiliary bias applying means applies an auxiliary bias voltage to the gap between the image information forming body and the fluid viscous flow generating member to apply an auxiliary electrostatic force, so that the toner, etc. The electrostatic force acts on the adhered substances and makes it easier to remove. The auxiliary bias voltage includes an oscillating voltage having only a DC bias voltage, an AC bias voltage only, or an oscillating voltage in which an AC bias voltage is superimposed on a DC bias voltage, and an auxiliary electrostatic force is given depending on which of these. .

Furthermore, a charge removing unit for making the specific charge of the toner uniform and a charge removing unit for removing the residual charge of the image information forming body are provided on the upstream side of the cleaning unit, and the adhered substances such as the toner such as the residual toner are removed. The adhesion to the image information forming body is reduced and cleaning is further facilitated.

[0026]

Embodiments of the cleaning method and apparatus for an image forming apparatus according to the present invention will be described below.

(Embodiment 1) FIG. 1 is a schematic configuration diagram of a cleaning device according to an embodiment of the present invention. The image information forming body 1 of the present embodiment includes an aluminum drum base and an organic photoconductor layer (OPC) formed on the outer peripheral surface of the drum base.
Layer) with an outer diameter of 80 mm and a length of 310 mm,
Predetermined peripheral speed (process speed), eg 175m
It is rotationally driven at m / s. The image information forming body 1 is not limited to the drum substrate, but may be in the form of a sheet.
Further, the material is not limited to aluminum.

The surface of the rotating image information forming body 1 is
After charging by a charger (not shown) to the opposite polarity to the toner, an electrostatic latent image is formed on the outer peripheral surface of the image information forming body 1 by exposure according to image information, and the toner is developed and visualized by a developer (not shown). The image is transferred onto a transfer body such as paper by a transfer device (not shown). At this time, the transfer residual toner 6 remains on the surface of the image information forming body 1.

The fluid viscous flow generating member of the cleaning means is made of an insulating or non-insulating material. For example, if it is a non-insulating material, a conductive or semi-conductive solid material containing a conductive metal material such as aluminum, copper, steel and their alloy materials, a conductive material such as carbon, Examples include porous or foamable polymer organic materials. If it is an insulating material, it can be constituted by a solid or hollow cylindrical roller such as rubber, plastic material, porous material, or foaming polymer organic material having insulating properties.
Alternatively, a multi-layer structure in which the cylindrical roller is coated with a conductive or semi-conductive polymer organic material containing a conductive material such as carbon can be used.

By constructing the fluid viscous flow generating member with a non-insulating material, it is possible to use a conductive metal material such as aluminum, copper, iron and steel and their alloy materials, and the strength, wear resistance, etc. An excellent fluid viscous flow generating member can be configured, and since it is a non-insulating material and has conductivity, an arbitrary bias voltage can be applied.

Further, by using a conductive or semi-conductive polymer organic material containing a conductive material such as carbon, FRP in which conductive fibers such as carbon fibers are dispersed in engineering plastic is used. Plastic materials, conductive engineering plastics and rubber, etc., as well as conductive engineering plastics such as solid, porous or foamable materials, conductive ceramics, functionally graded materials, etc. it can. By forming the fluid viscous flow generating member with an insulating material, for example, a plastic material such as polyester, polyethylene, acrylic, etc., which has no conductivity and good productivity, and a foamable polymer organic material such as urethane, conductive Ceramics, functionally graded materials, etc. can be used.

The viscous fluid flow generating member is, for example, 10 m in diameter.
m, a length of 310 mm, an aluminum solid cylindrical metal roller 2, the surface of which is smooth, and the image information forming body 1
The space 3 having a diameter of 200 μm is held therein. The size of the void 3 is not limited to 200 μm, and can be arbitrarily selected due to mechanical constraints, electrical constraints, and the like.
Usually, it is in the range of 200 μm to 500 μm, but the smaller it is, the more viscous the action is.

The metal roller 2 is rotated at a high speed, for example, at a peripheral speed of 3000 mm / s or more at which the viscous action becomes remarkable, preferably at 4000-15000 mm / s at which the viscous action becomes remarkable and mechanical restrictions are relaxed. Let At this time, an air flow which is a fluid viscous flow 7 is generated in the void 3 due to the fluid friction of the air. Since there is a velocity difference between the two wall surfaces of the vicinity of the surface of the metal roller 2 and the image information forming body, a viscous action of air represented by Newton's law of viscosity causes a viscous fluid flow 7 to generate the image. Shear stress is applied to the residual toner 6 on the surface of the information forming body.

The Newton's law of viscosity will be described in more detail with reference to FIG. A fluid (air in this embodiment) is filled between parallel walls having a relatively small distance Y between the two wall surfaces, the fixed wall B is fixed, and the moving wall A (upper plate) is moved at a velocity U.
Consider the case of moving in parallel with the fixed wall B at. In this case, the fluid in contact with the fixed wall B remains attached to the wall surface and does not move, and the fluid in contact with the moving wall A is dragged by the moving wall A and moves at a velocity U. At this time, the velocity distribution of the fluid is not linear,
The fluid moves along the moving wall A with a velocity gradient in the direction perpendicular to the flow represented by du / dy, and between the fluid at the position y from the fixed wall B and the fluid at the position y + dy. Shear stress acts due to the friction of each other.

The shear stress acting on each fluid layer between the wall surfaces is defined by τ
Then, τ = μ · U / Y (1) μ is the viscosity of the fluid corresponding to the lateral elastic coefficient of the elastic body, U is the moving speed of the moving wall A, Y is the distance between the two wall surfaces, and U / Y has the same physical meaning as the velocity gradient du / dy. To have.

Fluid viscosity μ is related to the rate at which fluid strain occurs. U is the peripheral speed of the metal roller 2 and Y is the gap 3
If the viscosity of air is constant, the shear stress τ on the surface of the image information forming body 1 is expressed by the equation (1), is proportional to the peripheral velocity U, and is inversely proportional to the size Y of the void 3. Therefore, the shear stress can be increased by reducing the size Y of the gap 3 as much as possible and increasing the peripheral velocity U of the metal roller 2 as much as possible.

The shearing stress acting can be increased depending on the surface shape / surface roughness of the metal roller 2, the presence / absence / shape of the hood for efficiently guiding the air flow, and the like. For example, to increase the contact area with air, that is, to increase the friction with air, knurling the surface, engraving grooves in the circumferential or axial directions, providing protrusions or depressions, or Can be increased by roughening the surface. Further, the shape is not limited to the cylindrical roller, and it may be one that increases friction with air and disturbs the flow, so one having a spiral screw in the rotation center direction, one having blades , Cross section is hexagonal,
It may have a cross section other than a circle, such as an octagon or a polygon such as a regular polygon.

With the above-mentioned structure, when the same shear stress is obtained for a smooth surface, the peripheral speed of the metal roller 2 is low, for example, 10,000 mm /
It can be set to s or less, mechanical constraints such as strength and life can be relaxed, and the same cleaning performance as when the peripheral speed is high can be obtained.

By rotating the metal roller 2 at the above-described peripheral speed and reducing the gap 3, the shear force due to the shear stress of the fluid viscous flow 7 is applied to the residual toner 6 by the image information forming body of the residual toner. It is made to act stronger than the adhesive force to 1 and peeled off from the surface. This peeled residual toner 6
Is applied to the collecting / conveying roller 4 as a collecting / conveying member by a collecting bias applying means 5 to apply a collecting bias voltage having a polarity opposite to that of the residual toner (negative voltage in the case of positive polarity toner). The peeled residual toner 6 is subjected to a Coulomb force represented by F = q · E (2) to electrostatically attract and collect it.

The collecting / conveying roller 4 is rotated at a peripheral speed ratio with the image information forming body 1 such that the recovered residual toner 6 does not scatter, for example, a peripheral speed ratio of 1 with respect to the process speed. The collecting and conveying roller 4, which is a collecting and conveying means,
For example, a solid aluminum cylindrical roller having a diameter of 20 mm and a length of 310 mm is used.

In the case of positive polarity toner, if the gap between the image information forming member 1 and the image forming member 1 is 500 μm, for example, the range where no discharge occurs, for example, the absolute value of the DC bias voltage is greater than the absolute value of the charging potential of the image information forming member 1. Is also large and 2.7k
By applying a DC bias voltage −2 kV, which is a recovery bias voltage by the recovery bias applying means 5 at V or less, an electric field strength of 4 MV / m can be applied. The Coulomb force due to the electric field strength becomes larger than the Coulomb force between the image information forming body 1 and the residual toner 6 and acts on the peeled residual toner 6, so that the residual toner 6
Is a positive polarity, the image information forming body 1 and the metal roller 2
It is possible to electrostatically attract and collect by the collecting and conveying roller 4 having a lower electric potential than that, and it is possible to prevent the peeled residual toner 6 from adhering to the image information forming body 1 or the metal roller 2.

Since the collecting / conveying roller 4 is required to have conductivity, not only aluminum but also a conductive metal material such as aluminum alloy material, copper, steel and their alloy materials, and conductive material such as carbon. It may be made of a non-insulating material such as a conductive or semi-conductive material containing a material having a property, and the shape thereof is not necessarily a cylindrical roller as long as the toner can be scraped off from the collecting and conveying roller 4. There is no.

Plastics such as FRP in which conductive fibers such as carbon fibers are dispersed in engineering plastics by being composed of a conductive or semi-conductive polymer organic material containing a material having conductivity such as carbon Use materials such as conductive engineering plastics and rubbers, as well as conductive engineering plastics such as solid, porous or expandable polymer organic materials, conductive ceramics, and functionally graded materials. You can

Electrostatically sucked by the collecting and conveying roller 4,
The collected collected toner 8 is scraped off from the collecting and conveying roller 4 by the blade 15 provided in contact with the collecting and conveying roller 4, and is collected in a collecting bottle.

(Embodiment 2) FIG. 3 has the same configuration as that shown in Embodiment 1, and when the residual toner 6 remaining on the surface of the image information forming body 1 is peeled off by the fluid viscous flow 7,
This is an example in which the auxiliary bias voltage is applied to the gap 3 between the image information forming body 1 and the metal roller 2 which is the fluid viscous flow generating member by the auxiliary bias applying means 9.

Since the fluid viscous flow generating member may be made of a non-insulating material, that is, having conductivity, for example, aluminum,
Consists of solid or hollow cylindrical rollers such as conductive metal materials such as copper, steel and their alloy materials, conductive or semi-conductive materials containing conductive materials such as carbon, and The same image information forming body 1 as in Example 1
To use.

As in the case of the first embodiment, the collecting / conveying roller 4 need only have a non-insulating material, that is, a conductive material. Therefore, a conductive metal material such as aluminum, copper, steel and their alloy materials can be used. Alternatively, it may be constituted by a solid or hollow cylindrical roller such as a conductive or semiconductive material containing a conductive material such as carbon. A plastic material such as FRP in which conductive fibers such as carbon fibers are dispersed in engineering plastic by being composed of a conductive or semi-conductive polymer organic material containing a material having conductivity such as carbon,
Conductive engineering plastics, rubbers, etc., and solid, porous or expandable polymer organic materials such as conductive engineering plastics, conductive ceramics, functionally graded materials, etc. can be used. .

The fluid viscous flow generating member is, for example, 10 m in diameter.
m, length 310 mm, solid aluminum roller 2 made of aluminum, and collecting and conveying roller 4 having a diameter of 20 m, for example.
m, length 310 mm, solid aluminum cylindrical roller. The metal roller 2 which is the fluid viscous flow generating member and the collecting and conveying roller 4 which is the collecting and conveying member do not necessarily have to be cylindrical rollers as shown in the first embodiment.

By using the above structure, the residual toner 6
In addition to the shearing force due to the fluid viscous flow 7, the Coulomb force expressed by the above equation (2) acts on the residual toner 6 which is the charged particles in the direction of the fluid viscous flow generating member, and not only the shearing force Since an electrostatic force is applied, the image information forming body 1 is easily peeled off from the surface.

If the gap 3 is set to 200 μm, for example, in the case of positive polarity toner, the range in which discharge does not occur, for example, the absolute value of the DC bias voltage is larger than the absolute value of the charging potential of the image information forming body 1, and 2. By applying a DC bias voltage of -1 kV as an auxiliary bias voltage by the auxiliary bias applying means 9 at a voltage of 7 kV or less, an electric field strength of 5 MV / m can be applied, and the Coulomb force corresponding to the charge amount of the residual toner 9 can be exerted. It can act on the residual toner.

The removed residual toner 6 is applied with a bias voltage having a polarity opposite to that of the residual toner (negative voltage in the case of a positive polarity toner) by the recovery bias applying means 5 to be removed as charged particles. The residual toner 6 is subjected to the Coulomb force expressed by the above-mentioned formula (2), and electrostatically attracted to the collecting / conveying roller 4 as a collecting / conveying member to collect it. The peeled residual toner 6 is collected by the collecting and conveying roller 4 by the Coulomb force by the auxiliary bias applying unit 9, the Coulomb force by the collecting bias applying unit 5, and the air flow by the fluid viscous flow.

The collecting / conveying roller 4 is rotated at a peripheral speed ratio with the image information forming body 1 such that the recovered residual toner 6 is not scattered, for example, a peripheral speed ratio of 1 with respect to the process speed.

In the case of positive polarity toner, if the gap between the image information forming body 1 and the image forming body 1 is 500 μm, for example, the range in which no discharge occurs, for example, the absolute value of the DC bias voltage is greater than the absolute value of the charging potential of the image forming body 1. Is also large and 2.7k
By applying the DC bias voltage −2.5 kV as the recovery bias voltage by the recovery bias applying means 5 at V or less, an electric field strength of 5 MV / m can be applied. Since the Coulomb force due to the electric field strength acts on the peeled residual toner 6, if the residual toner 6 has a positive polarity, the collecting and conveying roller 4 having a lower potential than the image information forming body 1 and the metal roller 2 is electrostatically charged. The residual toner 6 thus peeled off can be prevented from adhering to the image information forming body 1 or the metal roller 2.

When electrostatically attracted to the collecting and conveying roller 4,
The collected collected toner 8 is scraped off from the collecting and conveying roller 4 by the blade 15 provided in contact with the collecting and conveying roller 4, and is collected in a collecting bottle.

(Embodiment 3) FIG. 4 shows an example of a concrete embodiment of the bias applying method by the auxiliary bias applying means 9 shown in the second embodiment.

With the same configuration as that of the second embodiment, both the recovery bias applying means 5 and the auxiliary bias applying means 9 are used as a DC bias voltage applying device, and the absolute value of the DC bias voltage of the recovering bias applying means 5 is set to the auxiliary bias applying means 9. Is higher than the absolute value of the DC bias voltage of, for example, by the recovery bias applying unit 5, a DC bias voltage of −2.5 kV as the recovery bias voltage, and by the auxiliary bias applying unit 9.
DC bias voltage −0.8 kV as auxiliary bias voltage
It is possible to collect the residual toner 6 on the collecting and conveying roller 4 by applying.

In the case of the positive polarity toner, assuming that the gap between the toner and the image information forming body 1 is 500 μm, for example, the range in which no discharge occurs, for example, the absolute value of the DC bias voltage is greater than the absolute value of the charging potential of the image information forming body 1. Is also large and 2.7k
A voltage of 5.4 MV / m or less can be applied by applying a DC bias voltage of −2.7 kV as the recovery bias voltage by the recovery bias applying means 5 at a voltage of V or less. By applying the DC bias voltage -1 kV as the auxiliary bias voltage by the bias applying means 9, the electric field strength of 5 MV / m can be applied.

When the residual toner 6 has a positive polarity by applying the bias voltage as described above, the image information forming body 1
Can be electrostatically attracted to and collected by the collecting / conveying roller 4 having a lower potential than the metal roller 2 and the peeled residual toner 6 adheres to the image information forming body 1 and the metal roller 2. You can turn it off.

The collecting / conveying roller 4 is rotated at a peripheral speed ratio with the image information forming body 1 such that the recovered residual toner 6 is not scattered, for example, a peripheral speed ratio of 1 with respect to the process speed.

Since the collecting / conveying roller 4 has only to be conductive, not only aluminum but also a conductive metal material such as aluminum alloy material, copper, steel and their alloy materials, and conductive material such as carbon. It is also possible to use a non-insulating material such as a conductive or semi-conductive material containing a material having properties. FR that is made of conductive or semi-conductive polymer organic material containing conductive material such as carbon to disperse conductive fiber such as carbon fiber in engineering plastic.
Plastic materials such as P, conductive engineering plastics and rubbers, etc., and solid, porous or expandable polymer organic materials such as conductive engineering plastics, conductive ceramics, functionally graded materials Etc. can be used.

The collecting and conveying roller 4 is electrostatically attracted,
The collected collected toner 8 is scraped off from the collecting and conveying roller 4 by the blade 15 provided in contact with the collecting and conveying roller 4, and is collected in a collecting bottle.

(Embodiment 4) FIG. 5 shows an example of a concrete embodiment of the bias applying method by the auxiliary bias applying means 9 shown in the second embodiment.

When the recovery bias applying means 5 is a DC bias voltage applying device and the auxiliary bias applying means 9 is an AC bias voltage applying device in the same configuration as in the second embodiment, the residual toner 6 is electrostatically charged by the AC bias voltage. Reciprocating motion is given in a direction connecting the center of rotation between the image information forming body 1 and the metal roller 2 by a typical vibration force, and becomes a mist with air. In this state, the fluid viscous flow generating member of the cleaning means causes the fluid viscous flow to act, so that the fluid viscous flow is easily peeled off from the surface of the image information forming body 1, and the shear force due to the fluid viscous flow 7 causes both forces. It is removed from the surface of the image information forming body 1.

For example, when the gap 3 is 200 μm,
Regarding the frequency and the peak-to-peak voltage of the AC bias voltage, for example, the absolute value of one amplitude of the oscillating voltage of only the AC bias voltage is larger than the absolute value of the charging potential of the image information forming body 1, and 2 The condition is set to 0.7 kV or less, and the condition that the residual toner 6 easily vibrates electrostatically is set. The frequency of the AC bias voltage is 500 Hz to 10 kHz and the peak-to-peak voltage is 500 to 5 kVp-p. For example, the frequency of the AC bias voltage is 3 kHz and the peak-to-peak voltage is 2 k.
Apply Vp-p. The residual toner 6 after the removal is electrostatically sucked and collected by the collecting and conveying roller 4.

In the case of positive polarity toner, if the gap between the collecting and conveying roller 4 and the image information forming body 1 is 500 μm,
For example, the absolute value of the DC bias voltage is larger than the absolute value of the charging potential of the image information forming body 1 and is 2.7 kV or less within a range in which the discharge does not occur, and the recovery bias applying unit 5 uses the recovery bias voltage as the recovery bias voltage. An electric field strength of 5.4 MV / m can be applied by applying a DC bias voltage of -2.7 kV.

When the residual toner 6 has a positive polarity, the residual toner 6 can be electrostatically attracted and collected by the collecting and conveying roller 4 having a lower potential than the image information forming body 1 and the metal roller 2, and the peeled residue remains. The toner 6 can be prevented from adhering to the image information forming body 1 or the metal roller 2.

The collecting / conveying roller 4 is rotated at a peripheral speed ratio with the image information forming body 1 such that the collected residual toner 6 is not scattered from the collecting / conveying roller 4, for example, a peripheral speed ratio of 1 with respect to the process speed.

Since the collecting / conveying roller 4 is required to have conductivity, not only aluminum but also a conductive metal material such as aluminum alloy material, copper, steel and their alloy materials, and conductive material such as carbon. It is also possible to use a non-insulating material such as a conductive or semi-conductive material containing a material having properties. FR made of conductive fiber such as carbon fiber dispersed in engineering plastic by being composed of conductive or semi-conductive polymer organic material containing conductive material such as carbon
Plastic materials such as P, conductive engineering plastics and rubbers, etc., and solid, porous or expandable polymer organic materials such as conductive engineering plastics, conductive ceramics, functionally graded materials Etc. can be used.

When electrostatically attracted to the collecting and conveying roller 4,
The collected collected toner 8 is scraped off from the collecting and conveying roller 4 by the blade 15 provided in contact with the collecting and conveying roller 4, and is collected in a collecting bottle.

The AC bias voltage applied by the AC bias voltage applying device may be applied to the residual toner 6 by electrostatic vibration force. Therefore, the applied waveform of the AC bias voltage may be a sine wave, a rectangular wave, a triangular wave, a differentiated wave of a rectangular wave, an integrated wave, or the like, but is not limited to the applied waveform, and it vibrates at the zero potential. It goes without saying that any applied waveform may be used.

(Embodiment 5) FIG. 6 shows an example of a specific embodiment of the bias applying method by the auxiliary bias applying means 9 shown in the second embodiment.

With the same configuration as that of the second embodiment, the bias voltage applying device for applying the recovery bias applying means 5 to the DC bias voltage applying device and the auxiliary bias applying means 9 for applying the oscillating voltage obtained by superposing the AC bias voltage on the DC bias voltage. In the case of, the residual toner 6 is reciprocated in the direction connecting the center of rotation between the image information forming body 1 and the metal roller 2 by the electrostatic biasing force by the AC bias voltage, and further the DC bias is applied. It becomes mist with air due to electrostatic attraction due to voltage. In this state, the fluid viscous flow generating member of the cleaning means causes the fluid viscous flow to act, so that the fluid viscous flow is easily peeled off from the surface of the image information forming body 1, and the shear force due to the fluid viscous flow 7 causes both forces. The image information forming body 1
Is removed from the surface.

For example, when the gap 3 is 200 μm,
In a range where discharge does not occur, for example, the absolute value of one-sided amplitude of the oscillating voltage obtained by superimposing the AC bias voltage on the DC bias voltage is larger than the absolute value of the charging potential of the image information forming body 1 and is 2.7 kV or less. Further, the condition that the residual toner 6 is easily vibrated electrostatically is set. The frequency of the AC bias voltage is 500 Hz to 10 kHz, and the peak-to-peak voltage is 5
The frequency of the AC bias is 3 kHz and the peak-to-peak voltage 2 kVp-p is applied.

The absolute value of the DC bias voltage of the recovery bias applying means 5 is made higher than the absolute value of the DC bias voltage of the auxiliary bias applying means 9. For example, in the case of positive polarity toner, the gap between the collecting / conveying roller 4 and the image information forming body 1 is 5
When it is set to 00 μm, the recovery bias applying means 5 recovers a range where discharge does not occur, for example, the absolute value of the DC bias voltage is larger than the absolute value of the charging potential of the image information forming body 1 and is 2.7 kV or less. A DC bias voltage of −2.7 kV as a bias voltage, and a DC bias voltage of − as an auxiliary bias voltage by the auxiliary bias applying unit 9.
Apply 200V.

When the residual toner 6 has a positive polarity, the residual toner 6 can be electrostatically sucked and collected by the collecting and conveying roller 4 having a lower potential than the image information forming body 1 and the metal roller 2, and the peeled residual It is possible to prevent the toner 6 from adhering to the image information forming body 1 or the metal roller 2.

The collecting / conveying roller 4 is rotated at a peripheral speed ratio with the image information forming body 1 at a value at which the residual toner 6 collected does not scatter from the collecting / conveying roller 4, for example, at a peripheral speed ratio of 1 with respect to the process speed. .

Since the collecting / conveying roller 4 is required to have conductivity, not only aluminum but also a conductive metal material such as aluminum alloy material, copper, steel and their alloy materials, and conductive material such as carbon. It is also possible to use a non-insulating material such as a conductive or semi-conductive material containing a material having properties. FR that is made of conductive or semi-conductive polymer organic material containing conductive material such as carbon to disperse conductive fiber such as carbon fiber in engineering plastic.
Plastic materials such as P, conductive engineering plastics and rubbers, etc., and solid, porous or expandable polymer organic materials such as conductive engineering plastics, conductive ceramics, functionally graded materials Etc. can be used.

When electrostatically attracted to the collecting and conveying roller 4,
The collected collected toner 8 is scraped off from the collecting and conveying roller 4 by the blade 15 provided in contact with the collecting and conveying roller 4, and is collected in a collecting bottle.

The AC bias voltage applied by the bias voltage applying device for applying the vibration voltage in which the AC bias voltage is superimposed on the DC bias voltage may be applied to the residual toner 6 by electrostatic vibration force. Therefore, the applied waveform of the AC bias voltage may be a sine wave, a rectangular wave, a triangular wave, a differential wave of a rectangular wave, an integrated wave, or the like, but is not limited to the applied waveform, and a DC voltage on which an AC bias is superimposed is applied. It goes without saying that an applied waveform that oscillates at the potential of the bias voltage may be used.

(Embodiment 6) This embodiment is an example of a concrete embodiment of the bias application conditions by the auxiliary bias applying means 9 shown in the embodiments 4 and 5. Among the bias applying methods of the auxiliary bias applying means 9, the frequency is 500 Hz to 10 k as an AC bias voltage applying condition when applying an oscillating voltage based on only an AC bias or an oscillating voltage in which an AC bias voltage is superimposed on a DC bias voltage.
Hz and a peak-to-peak voltage of 500 V to 5 kVp-p, preferably a frequency of 1.5 to 5 kHz due to stability such as cleaning efficiency, toner flight threshold voltage and flight resonance frequency.
Moreover, by setting the peak-to-peak voltage to 1 to 4 kVp-p, the degree of the residual toner 6 and the air becoming a mist becomes high,
The image information forming body 1 is easily peeled off from the surface.
Then, as shown in the graphs of FIGS. 7 and 8 showing an example of the relationship of the cleaning efficiency, when the specific charge of the toner is 13 μ / C, the cleaning efficiency showing the cleaning property is significantly improved as compared with the other ranges. The cleaning efficiency is dramatically improved as compared with the case where the auxiliary bias voltage is not applied and the case where the direct current bias voltage is applied as the auxiliary bias voltage.

The cleaning efficiency representing the cleaning property in FIGS. 7 and 8 is represented by measuring the optical density of the toner adhering on the image information forming body 1 before and after cleaning. Specifically, the toner on the image information forming body 1 is peeled off with a tape based on JIS K7611 “Method for measuring photographic characteristics of general-purpose photographic printing paper”. At the time of this peeling, a 1 kg weight is slowly put on and reciprocated twice. After that, the tape is peeled off from the surface of the image information forming body 1 at an angle of 180 degrees. At this time, the optical density of the toner adhered to the tape is measured by a reflection densitometer.

This density was measured before and after cleaning,
The cleaning efficiency is calculated by the following equation (3). When the cleaning efficiency is CR and the reflection density ratio before and after cleaning is R, R = density after cleaning / density before cleaning CR = (1−R) × 100 (3)

The residual toner 6 in the form of mist due to the oscillating voltage based on only the AC bias or the oscillating voltage obtained by superimposing the AC bias voltage on the DC bias voltage causes image information to be generated by the fluid viscous flow 7 generated by the fluid viscous flow generating member. It is peeled off from the forming body 1 and cleaned.

The residual toner 6 after the removal is electrostatically attracted and collected by the collecting and conveying roller 4 by the collecting bias voltage applied to the collecting and conveying roller 4 which is a collecting and conveying member.

The collecting and conveying roller 4 is electrostatically sucked,
The collected collected toner 8 is scraped off from the collecting and conveying roller 4 by the blade 15 provided in contact with the collecting and conveying roller 4, and is collected in a collecting bottle.

(Embodiment 7) FIG. 9 has the same basic configuration as that of Embodiment 1, but the adhesive force of the residual toner 6 attached to the surface of the image information forming body 1 to the image information forming body 1. In order to weaken the static electricity, a static elimination step by means of a static elimination means (for example, a corona charger such as a corotron or a scorotron) for making the specific charge of the toner uniform on the upstream side of the cleaning means, and a static elimination means for removing the residual charges of the image information forming body ( For example, an example in the case of performing a static elimination step using a static elimination lamp) will be described.

The viscous fluid flow generating member may have the same structure as that of the first embodiment. For example, the viscous fluid flow generating member is a solid metal roller 2 made of aluminum and the gap 3 is 20.
It can be 0 μm.

By appropriately applying a charge having a polarity opposite to the polarity of the residual toner 6 by the corona charger, the residual toner 6
Since the specific charges of the residual toner 6 are uniform and the residual charge of the image information forming body 1 can be removed by the charge eliminating lamp, the electrostatic adhesion force (Coulomb force) of the residual toner 6 to the image information forming body 1 can be weakened. The cleaning efficiency can be improved as compared with the case where there is no static elimination step by the static elimination means.

The residual toner 6 removed from the image information forming body 1 can be collected in the same manner as in the above-mentioned embodiment.

[0090]

As described above, according to the cleaning method and apparatus for an image forming apparatus of the present invention, it is possible to non-contactly clean the adhered matter such as toner adhered on the image information forming body. No stress is applied to the information forming body, and there is no risk of damage.

Further, since it is not affected by the developing method such as magnetic / non-magnetic, one-component / two-component developing method, it is effective in colorization, and stable cleaning performance can be obtained even in a high speed machine and a large machine, and a good image can be obtained. It has the effect of ensuring quality for a long time.

Further, the toner particles used in the electrophotographic process have a rough surface shape produced by a conventional grinding method or a cleaning blade having a smooth surface shape produced by a polymerization method or the like. Since it is possible to remove the toner that is difficult to clean by a cleaning method of contacting or abutting the same, there is an effect that a good cleaning performance is obtained, which is hardly affected by the shape, material, characteristics, etc. of the toner.

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram of a cleaning device of an image forming apparatus embodying the present invention.

FIG. 2 is a principle diagram for generating a viscous fluid flow.

FIG. 3 is a schematic configuration of a cleaning device of an image forming apparatus in which an auxiliary bias applying unit 9 for applying a bias voltage is added to a gap 3 between an image information forming body 1 and a fluid viscous flow generating member 2 to improve cleaning performance. It is a figure.

FIG. 4 is a schematic configuration diagram of a cleaning device of an image forming apparatus in which an auxiliary bias voltage is applied by an auxiliary bias applying unit 9 so as to apply a DC bias voltage.

FIG. 5 is a schematic configuration diagram of a cleaning device of an image forming apparatus in which an auxiliary bias voltage is applied by an auxiliary bias applying unit 9 so that an oscillating voltage of only an AC bias voltage is applied.

FIG. 6 is a schematic configuration diagram of a cleaning device of an image forming apparatus in which an auxiliary bias voltage is applied by an auxiliary bias applying unit 9 so as to apply an oscillating voltage in which an AC bias voltage is superimposed on a DC bias voltage.

FIG. 7 is a graph showing an example of the relationship between the frequency of AC bias voltage and cleaning efficiency.

FIG. 8 is a graph showing an example of a relationship between a peak-to-peak voltage of an AC bias voltage and cleaning efficiency.

FIG. 9 is an image formation provided with a corona charger that is a charge eliminating unit that makes the specific charge of toner uniform on the upstream side of the fluid viscous flow generating member, and a charge eliminating lamp that is a charge eliminating unit that removes residual charges of the image information forming body. FIG. 3 is a schematic configuration diagram of a cleaning device of the apparatus.

FIG. 10 is a schematic configuration diagram of a conventional electrophotographic image forming apparatus.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Image information forming body 2 Fluid viscous flow generation member 3 Gap 4 Recovery conveyance member 5 Recovery bias application means 6 Residual toner 7 Fluid viscous flow 8 Recovery toner 9 Auxiliary bias application means 15 Blade 16 Corona charger 17 Static elimination lamp

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Masaaki Ozaki 22-22 Nagaikecho, Abeno-ku, Osaka-shi, Osaka Prefecture Sharp Corporation (72) Masanori Yamada 22-22 Nagaike-cho, Abeno-ku, Osaka Prefecture, Osaka Within the corporation

Claims (20)

[Claims] 1. A method for cleaning an image forming apparatus, which develops and transfers an electronic latent image obtained on the surface of an image information forming body by an electrophotographic method and transfers the latent image in the vicinity of the image information forming body. And the toner on the image information forming body is generated by the fluid viscous flow generated by the fluid viscous flow generating member that is disposed around the image information forming body and rotates about an axis perpendicular to the axis perpendicular to the surface of the image information forming body. A method for cleaning an image forming apparatus, characterized in that adhered matters such as toner are removed and cleaned, and the removed adhered matters such as toner are collected by a collecting and conveying member. 2. The cleaning method for an image forming apparatus according to claim 1, wherein a recovery bias voltage is applied to a gap between the recovery conveyance member and the image information forming body. 3. The cleaning method for an image forming apparatus according to claim 1, wherein an auxiliary bias voltage is applied to a gap between the viscous fluid flow generating member and the image information forming body. 4. The cleaning method for an image forming apparatus according to claim 2, wherein an auxiliary bias voltage is applied to a gap between the viscous fluid flow generating member and the image information forming body. 5. The DC bias voltage is applied as the auxiliary bias voltage when the auxiliary bias voltage is applied to the gap between the fluid viscous flow generating member and the image information forming body. Item 4. A method for cleaning an image forming apparatus according to item 4. 6. When an auxiliary bias voltage is applied to the space between the fluid viscous flow generating member and the image information forming body, an AC bias voltage is added to the oscillation voltage of only the AC bias voltage or the DC bias voltage as the auxiliary bias voltage. The cleaning method for an image forming apparatus according to claim 3, wherein any one of the superposed oscillating voltages is applied. 7. The AC bias voltage of the oscillating voltage has a frequency of 500 Hz to 10 kHz and a peak-to-peak voltage of 50.
7. The cleaning method for an image forming apparatus according to claim 6, wherein the cleaning voltage is 0 V to 5 kVp-p. 8. The frequency of the alternating bias voltage of the oscillating voltage is 1.5 kHz to 5 kHz, and the peak-to-peak voltage is 1 k.
7. The method for cleaning an image forming apparatus according to claim 6, wherein the cleaning method is V to 4 kVp-p. 9. The method according to claim 1, wherein at least one of a static elimination step of making the specific charge of the toner uniform and a static elimination step of removing the residual charges of the image information forming body is performed before cleaning. 9. The method for cleaning an image forming apparatus according to any one of items 8. 10. A cleaning device of an image forming apparatus, which develops and transfers an electronic latent image obtained on the surface of an image information forming body by an electrophotographic method with toner or the like, and holds a slight gap near the image information forming body. A fluid viscous flow generating member that generates a fluid viscous flow by rotating about an axis orthogonal to an axis perpendicular to the surface of the image information forming body,
A cleaning device for an image forming apparatus, comprising: a cleaning unit that removes adhered substances such as toner on the image information forming body; and a collecting and conveying unit that collects the adhered substances such as removed toner by a collecting and conveying member. apparatus. 11. A recovery bias applying unit adapted to apply an auxiliary bias voltage to a gap between the recovery transport member and the image information forming body, wherein the recovery transport member of the recovery transport unit is made of a non-insulating material. Claim 1 characterized by the above-mentioned.
A cleaning device of the image forming apparatus described in 0. 12. An image forming apparatus according to claim 10, further comprising an auxiliary bias applying unit for applying an auxiliary bias voltage in a space between the fluid viscous flow generating member of the cleaning unit and the image information forming body. Equipment cleaning device. 13. An image forming apparatus according to claim 11, further comprising auxiliary bias applying means for applying an auxiliary bias voltage in a gap between the fluid viscous flow generating member of the cleaning means and the image information forming body. Equipment cleaning device. 14. The cleaning device for an image forming apparatus according to claim 12, wherein the auxiliary bias applying unit applies a DC bias voltage. 15. The auxiliary bias applying means applies a bias voltage of either an oscillating voltage of only an AC bias voltage or an oscillating voltage in which an AC bias voltage is superimposed on a DC bias voltage. The cleaning device for an image forming apparatus according to claim 13. 16. The auxiliary bias applying means sets the frequency of the alternating bias voltage of the oscillating voltage to 500 Hz to 10 Hz.
kHz and a peak-to-peak voltage of 500 V to 5 kVp-
The cleaning device for an image forming apparatus according to claim 15, wherein p is applied. 17. The auxiliary bias applying means sets the frequency of the alternating bias voltage of the oscillating voltage to 1.5 kHz to 5 kHz.
kHz, and 1 kV to 4 kVp-p as peak-to-peak voltage
16. The cleaning device for an image forming apparatus according to claim 15, wherein the cleaning device is applied. 18. The cleaning device for an image forming apparatus according to claim 10, wherein the fluid viscous flow generating member of the cleaning means is made of an insulating material. 19. The fluid viscous flow generating member of the cleaning means is made of a non-insulating material.
18. The cleaning device for an image forming apparatus according to claim 17. 20. An upstream side of the cleaning means is provided with at least one of a neutralization means for making the specific charge of the toner uniform and a neutralization means for removing the residual charge of the image information forming body. The cleaning device for an image forming apparatus according to claim 19.