JP2001117329A - Image forming device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an image forming device where a service life of a cleaning member is prolonged by maintaining a good function of the cleaning member for a longer period of time to eliminate foreign matter in the cleaning member that eliminates the foreign matter that is attached to an electrifying member. SOLUTION: In the device, widths of each member of the image forming device are set so that width α of the electrifying member 9 >= width β of a cleaning member 18 > width γ of developing members 13a, 14a, 15a and 16a > width δ of the cleaning member 10 > width ε of image range on OPC 2. Toner that is leaked from space at both ends of a cleaning member 18, toner that is leaked from space at both ends of a developing member, worn powder of a photoreceptor caused by contact with the developing member or toner slipped through a worn part of the photoreceptor are accumulated localized in a place outside a cleaning range of the cleaning member 10 of the electrifying member 9. The service life of the cleaning member 10 is prolonged since localized existence of the accumulated matter inside the cleaning member is eliminated for cleaning of the accumulated matter is not carried out by the cleaning member 10.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rotatable charging member such as a charging roller which is in contact with a rotatable photosensitive member, charges the photosensitive member while rotating, and forms an electrostatic latent image on the charged photosensitive member. Belongs to the technical field of an image forming apparatus that forms an image by forming an image, and in particular, a cleaning member provided so as to be able to be separated from and attached to the charging member, adheres to the charging member by contacting the charging member. It belongs to the technical field of an image forming apparatus designed to remove foreign matter such as toner.

[0002]

2. Description of the Related Art An image forming apparatus such as an electrostatic copying machine or a printer is provided with a charging device for charging a photosensitive member, and corona charging has been widely used as a charging device. However, since the corona charging generates ozone and nitrogen oxides and adheres to the surface of the photoreceptor, there is a problem that an image defect is caused.

A contact charging system in which a charging member made of, for example, urethane rubber or the like to which a voltage is applied is brought into contact with the photosensitive member to charge the photosensitive member is proposed in Japanese Patent Laid-Open No. 63-149668. Have been. According to the contact charging method, the problem caused by the corona charging described above is solved. However, in the contact charging method, since the charging member is in contact with the photoreceptor, foreign substances such as toner on the photoreceptor slipped from the cleaning device and toner scattered from the developing device adhere to the surface of the charging member. In particular, in recent years, the particle size of the toner has been reduced or the amount of the flowability improver added to the toner has been increased, and the cleaning property has deteriorated. Thus, the slip-through toner is pressed against the nip portion between the charging member and the photosensitive member, and adheres more firmly as the charging member rotates.

For this reason, an image forming apparatus provided with a cleaning member for removing foreign substances such as toner adhered to the surface of a charging member has been disclosed in, for example, Japanese Patent No. 2853208 and Japanese Patent Application Laid-Open No. 07-128954. Proposed. If the cleaning member of these image forming apparatuses is constantly in contact with the charging member, the surface of the charging member will be damaged and charging failure will occur. The cleaning member is cleaned by rotating the charging member in contact with the charging member only when cleaning the charging member, and is set to be separated from the charging member when the charging member is not cleaned. Has become. In this case, the cleaning of the charging member is generally performed regularly, and therefore, the operation of separating and connecting the cleaning member is also performed regularly. According to the image forming apparatus provided with the cleaning member, the surface of the charging member is cleaned, and the charging of the photoconductor is improved.

[0005]

By repeating the cleaning of the charging member by the cleaning member, foreign matters such as toner removed from the charging member gradually accumulate on the cleaning member. On the other hand, an end face sealing material is provided opposite to both ends of the cleaning blade, and the end face sealing material prevents toner from leaking from both sides of the cleaning blade toward the charging member. However, since there is a gap between the end of the cleaning blade and the end face sealing material,
Some toner leakage occurs through this gap. Also, opposite end seals are provided on both ends of a developing member such as a developing roller of a developing device, so that toner is prevented from leaking from both sides of the developing member toward the charging member. However, since a gap also exists between the end of the developing member and the end face sealing material, a slight leakage of toner similarly occurs through this gap. Since each of these toner leaks is larger than the toner leak in the image area,
A large amount of toner adheres to both ends of the charging member.

If a large amount of toner adheres to both ends of the charging member in a biased manner as described above, the cleaning member also cleans a portion of the charging member that has a large amount of toner adhered thereto when cleaning the charging member. Of the cleaning member rapidly decreases and saturates relatively early, shortening the life of the cleaning member. Therefore, not only is the cleaning member unable to effectively remove foreign matter from the charging member, but also it becomes impossible to remove the foreign matter relatively early. Even if the cleaning member is provided, the photosensitive member can be relatively quickly removed. It causes poor charging of the body.

SUMMARY OF THE INVENTION The present invention has been made in view of such circumstances, and an object of the present invention is to provide a cleaning member which removes foreign matter adhering to a charging member so that the foreign matter removing ability can be maintained satisfactorily for a long time. Accordingly, an object of the present invention is to provide an image forming apparatus capable of extending the life of a cleaning member.

[0008]

In order to solve this problem, the present invention is directed to a photoreceptor on which an electrostatic latent image is formed and a photoreceptor charged while rotating while being in contact with the photoreceptor. A developing device for developing the electrostatic latent image on the photoconductor; a cleaning device for cleaning the photoconductor after transferring the developed image on the photoconductor; An image forming apparatus including at least a cleaning member that is provided so as to be capable of contacting and cleans the charging member, wherein an image area on the photoconductor on which an image is formed, a charging member of the charging device, and a cleaning member of the cleaning device. Each width of the cleaning member and the cleaning member is, respectively, the width of the charging member ≧
The width of the cleaning member> the width of the cleaning member> the width of the image area on the photoconductor is set. Further, according to the invention of claim 2, the width of the developing member of the developing device is such that the width of the charging member ≧ the width of the cleaning member> the width of the developing member> the width of the cleaning member> the width of the image area on the photoconductor. It is characterized by being set.

[0009]

In the image forming apparatus according to the present invention, the width of the charging member ≧ the width of the cleaning member> the width of the cleaning member> the width of the image area on the photosensitive member. The toner leaking toward the charging member from the gaps at both ends of the charging member adheres and accumulates outside the cleaning area of the charging member by the cleaning member. In this case, the amount of toner leaking through these gaps is larger than the amount of toner leaking in the image area on the photoconductor, and therefore, the amount of toner that adheres and accumulates outside the cleaning area of the charging member increases. However, since the location of the charging member where a large amount of toner adheres and accumulates is outside the cleaning area by the cleaning member, when the cleaning member removes foreign matter from the charging member, the cleaning member uses the charging member where the large amount of toner adheres and accumulates. Never clean the place.

Therefore, a large amount of toner does not unevenly adhere and accumulate on the cleaning member, and the uneven distribution of toner in the cleaning member is eliminated. Thereby, the foreign matter removing ability of the cleaning member does not rapidly decrease and does not saturate relatively early,
The life of the cleaning member is prolonged. As a result, the removal of foreign matter from the charging member by the cleaning member is effectively performed over a long period of time, and the occurrence of poor charging in the image area of the photoconductor is reduced.

In particular, in the present invention, the width of the charging member is greater than the width of the cleaning member> the width of the developing member> the width of the cleaning member> the width of the image area on the photosensitive member. The toner leaking from the gaps at both ends to the charging member via the cleaning member similarly adheres and accumulates at a location outside the cleaning region of the charging member. In this case, the amount of toner leaking through these gaps is larger than the amount of toner leaking in the image area on the photoconductor, so that a large amount of toner adheres and accumulates outside the cleaning area of the charging member. However, since the location of the charging member where the toner leaking from the gaps at both ends of the developing member adheres and accumulates is outside the cleaning area, the cleaning member does not clean this location as described above.

Accordingly, the toner leaking through the gaps at both ends of the developing member can be cleaned in the same manner as described above.
A large amount of toner does not adhere to and accumulate at zero, and uneven distribution of accumulated toner in the cleaning member 10 is eliminated. As a result, the life of the cleaning member is extended as described above, and the cleaning member effectively removes foreign matter from the charging member for a long period of time.

Further, the contact portion between the end portion of each developing member and the photoreceptor wears the photosensitive layer more than other portions of the photoreceptor due to the concentration of stress at the end portion. The amount of toner that slips through increases. However, like the toner leaking from the gaps at both ends of the developing member, the abrasion powder and the slip-through toner adhere to and accumulate in a location of the charging member outside the cleaning area of the cleaning member, so that the cleaning member The same operation as described above is performed without cleaning the place of the charging member where the abrasion powder and the slip-through toner adhere and accumulate.

[0014]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a view schematically showing a full-color intermediate transfer type image forming apparatus to which an example of an embodiment of the image forming apparatus of the present invention is applied. As shown in FIG. 1, an image forming apparatus 1 of this example includes a photoconductor (hereinafter, also referred to as OPC) 2, a charging device 3, an exposure device 4, a developing device 5, an intermediate transfer device 6, and a cleaning device 7.
And a transfer device (not shown) for transferring the intermediate transfer image transferred to the transfer belt 6a of the intermediate transfer device 6 to a transfer material such as transfer paper, and a fixing device for fixing the transfer image transferred to the transfer material. It has. Charging device 3,
The exposure device 4, the developing device 5, the intermediate transfer device 6, and the cleaning device 7 include an OPC as in the conventional image forming apparatus.
2 are arranged clockwise in the figure in these order.

As shown in FIG. 1, the charging device 3 includes an OPC
A charging member 9 such as a charging roller rotatably supported by a housing 8 to contact the OPC 2 and charge the OPC 2;
A cleaning member 10 for cleaning the surface of the charging member 9, the cleaning member 10 being provided so as to be detachable from the charging member 9,
, And a holding member 11 that operates so as to move the cleaning member 10 toward and away from the charging member 3.
An elastic member 12 made of a spring or the like is provided on the surface opposite to the side holding the cleaning member 10. In the illustrated state, the cleaning member 10 is in contact with the charging member 3 by the elastic force of the elastic member 12, but the cleaning member 10 and the holding member 11 are not shown, but are known cleaning member separation / contact driving means. Thereby, it can be set in a state separated from the charging member 3 against the elastic force of the elastic member 12. An electromagnetic solenoid, an electric motor, or the like can be used as the known cleaning member separating / contacting driving means. Any cleaning member separation / contact driving means including the contact driving means can be used. However, the cleaning member separation / contact driving means itself is not a characteristic part of the present invention, and a description thereof will be omitted. In a normal state where the charging member 9 is not cleaned, the cleaning member 10 is kept separated from the charging member 9, and the cleaning member 1 is
0 is set to the state shown in the drawing in contact with the charging member 9.

The charging device 3 is disclosed in the aforementioned Japanese Patent No. 2853.
In the image forming apparatus 1 using one process cartridge in which the photosensitive member 2 is accommodated as disclosed in Japanese Patent Publication No. 208-208, the image forming apparatus 1 is provided in this process cartridge and disclosed in Japanese Patent Application Laid-Open No. 07-128954. In the image forming apparatus 1 in which the cleaning member 10 is provided in the image forming apparatus main body, the cleaning member 10 is provided together with the image forming apparatus main body.

The developing device 5 includes yellow, magenta, cyan, and black developing devices 13, 14, 15, and 16, similarly to the developing device of the conventional full-color image forming apparatus. Containers 13, 14, 15, 16 are OPC
2 are arranged along the outer periphery. In that case, the arrangement order of the developing units 13, 14, 15, 16 of each color is not limited to the above-mentioned order, but is arbitrarily set. In the following description, for convenience of description, each developing unit 1 is arranged in the order of the above-described colors, that is, in the order of yellow, magenta, cyan, and black.
It is assumed that 3, 14, 15, and 16 are provided.

Each of the developing units 13, 14, 15, 16 has a developing member 13a, 14a, 15a, 16a such as a developing roll, and these developing members 13a, 14a, 15a, 16a.
Are designed to convey yellow, magenta, cyan, and black toners adhered to their surfaces, respectively, toward the OPC 2. The cleaning device 7 also includes a cleaner housing 17 and a cleaning member 18 such as a cleaning blade, like the conventional full-color image forming apparatus. In that case, cleaner housing 1
7 is formed integrally with the housing 8 of the charging device 3 as shown. Note that the cleaner housing 17 can be formed separately from the housing 8.

As shown in FIG. 2, in the image forming apparatus 1 of this embodiment, similarly to the conventional image forming apparatus, the sealing member 19 is opposed to the end faces of both ends of the cleaning member 18 and has a slight gap. , 20 are provided respectively. These seal members 19 and 20 prevent the toner from leaking from the sides of both ends of the cleaning member 18 toward the charging member 9. Further, each of the developing devices 13, 14, 15,
Similarly, the developing members 13a, 14a, 1
Seal members 21 and 22 are respectively disposed opposite to the end faces of both ends of 5a and 16a with a slight gap.

Further, in the image forming apparatus 1 of this embodiment, the charging member 9, the cleaning member 10, and the developing members 13a, 14a, 15
The widths (lengths in the direction orthogonal to the paper surface in FIG. 1) of the cleaning members 18a and 16a are set as follows. That is, the width α of the charging member 9 ≧ the width β of the cleaning member 18> the developing members 13a, 14a, 15a, 1
6a> the width δ of the cleaning member 10> the width ε of the image area on the OPC2.

The image forming apparatus 1 of the example configured as described above.
The operation of will be described. When the image forming apparatus 1 is operated to form an image, the charging member 9 and the OPC 2 are rotated as in a conventional general image forming apparatus, and the charging member 9 is rotated.
After the surface of the OPC 2 is charged, the exposure device 4 exposes the charged portion on the OPC 2 as an electrostatic latent image. Then, the electrostatic latent images on the OPC 2 are developed by yellow, magenta, cyan, and black developing units 13, 14, 15,
Then, the developed image on the OPC 2 is sent to the transfer device via the intermediate transfer device 6 and color-matched by the transfer device and transferred to a transfer material. By fixing by the apparatus, a desired image can be obtained on the transfer material.

After the developed image is transferred to the transfer material, the residual toner remaining on the OPC 2 is removed by the cleaning member 18 of the cleaning device 7 and stored in the cleaner housing 17. Thus, the image forming apparatus 1 completes the image formation, and after the OPC 2 is neutralized, the OPC 2 is charged again by the charging member 9 for the next image formation, and the same image forming operation is performed thereafter.

By the way, after the transfer, the residual toner remaining on the OPC 2 is
2 and is accommodated in the cleaner housing 17, but a part thereof is not removed, but passes through the cleaning blade 18 and moves toward the charging member 9, and adheres to the charging member 9. Become like Further, the toner scattered from the developing device during the image formation for a predetermined period may adhere to the charging member 9, or the scattered dust and dust around the photoconductor 2 may adhere to the charging member 9. . For this reason, in the image forming apparatus 1 of this example, the foreign matter attached to the charging member 9 is periodically removed by the cleaning member 10.

When the cleaning member 10 removes foreign matter from the charging member 9, the cleaning member 10 which is separated from the charging member 9 except for the cleaning operation is actuated by the cleaning member separation / contact driving means by the elastic force of the elastic member 12. , With a predetermined pressing force, and the charging member 9 is rotated in this state. Thus, as described above, the foreign matter adhering to and accumulating on the charging member 9 after passing through the cleaning member 18, the foreign matter adhering to and accumulating on the charging member 9 while being scattered from the developing device during image formation for a predetermined period, and Foreign substances such as dust and dust that scatter around the body 2 and adhere to and accumulate on the charging member 9 are removed by the cleaning member 10. The foreign matter removed by the cleaning member 10 is accommodated in the cleaner housing 17 or, if a housing portion is provided separately from the cleaner housing 17, is housed in the housing portion.

In the image forming apparatus 1 of this embodiment,
However, the end of the cleaning member 18 and the sealing members 19, 2
0 and the gap a₁, a_TwoExisted
These gaps a₁, a_TwoThrough the charging member 9
Leaks towards you. In that case, the image forming apparatus of this example
1, the width α of the charging member 9 and the width of the cleaning member 18
β, the width δ of the cleaning member 10 and the image area on the OPC 2
The width ε is the width α of the charging member 9 ≧ the width of the cleaning member 18.
β> width of cleaning member 10 δ> width ε of image area on OPC2
, The toner leaking toward the charging member 9
Is biased outside the cleaning area of the charging member 9 by the cleaning member 10
It becomes attached and accumulated. In that case, the gap a ₁, a_TwoThrough
The toner that leaks out is the toner in the image area of OPC2.
More than the leakage, so the charging member 9 is biased out of the cleaning area
The amount of toner deposited and accumulated also increases. But many tona
The location of the charging member 9 where the toner adheres and accumulates is the cleaning member 1
0, the band is outside the cleaning area, and
When removing foreign matter from the electrical member 9, the cleaning member 10 removes a large amount of toner.
Cleaning the place of the charging member 9 where the toner accumulates unevenly
There is no.

Accordingly, a large amount of toner is not unevenly attached to and accumulated on the cleaning member 10, and the uneven distribution of the accumulated toner in the cleaning member 10 is eliminated. As a result, the foreign matter removing ability of the cleaning member 10 does not rapidly decrease and does not saturate relatively early, and the life of the cleaning member 10 is extended. As a result, the removal of foreign matter from the charging member 9 by the cleaning member 10 is effectively performed for a long period of time, and the occurrence of poor charging in the image area of the OPC 2 is reduced.

On the other hand, developing members 13a, 14a, 15a, 1
Since gaps b ₁ , b ₂ also exist between each end of 6 a and the sealing members 21, 22, these gaps b ₁ , b ₂
Through the cleaning member 18, the toner leaking to the cleaning member 18 passes through the cleaning member 18 and moves toward the charging member 9. In this case, in the image forming apparatus 1 of this example, the width α of the charging member 9, the width β of the cleaning member 18, the developing members 13a, 1
4a, 15a, 16a, the width δ of the cleaning member 10 and the width ε of the image area on the OPC 2 are such that the width α of the charging member 9 ≧ the width β of the cleaning member 18> the developing members 13a, 14a, 1
Since the width γ of 5a and 16a is set to be greater than the width δ of the cleaning member 10> the width ε of the image area on the OPC 2, the toner that has slipped from the cleaning member 18 is outside the cleaning area of the charging member 9 by the cleaning member 10. It accumulates and accumulates in a part of the area. At this time, the amount of toner leaking through the gaps b ₁ and b ₂ is larger than the amount of toner leaking in the image area of the OPC ₂ , so that the amount of toner that adheres and accumulates outside the cleaning area of the charging member 9 increases. However, because many places in the charging member 9 which toner adheres accumulates unevenly a cleaning area outside by the cleaning member 10, as in the case where the above-described toner leakage through the gap a _1, a _2, charging by the cleaning member 10 When removing foreign matter from the member 9, the cleaning member 10 does not clean the location of the charging member 9 where a large amount of toner adheres and accumulates unevenly.

Therefore, the developing members 13a, 14a, 15
The toner leaking through the gaps b ₁ , b ₂ at both ends of the cleaning member 18 is also fixed to the gaps a ₁ , a _{2 at} both ends of the cleaning member 18.
As in the case of the toner leaking through the cleaning member 10, a large amount of toner does not unevenly adhere and accumulate on the cleaning member 10, and the uneven distribution of the accumulated toner in the cleaning member 10 is eliminated. Accordingly, the foreign matter removing ability of the cleaning member 10 does not rapidly decrease and does not saturate relatively early, and the life of the cleaning member 10 is extended. Therefore, the foreign matter removal of the charging member 9 by the cleaning member 10 is effective for a long time. And the occurrence of charging failure in the image area of the OPC 2 is reduced.

Further, each of the developing members 13a, 14a, 15a,
At the contact portion between the end portion 16a and the OPC 2, the wear of the photosensitive layer is larger than that of the other portion of the OPC 2 due to the concentration of the stress at the end portion. However, these abrasion powders and slip-through toner are charged to the charging member 9 outside the cleaning area by the cleaning member 10 as in the case of the toner leaking from the gaps b ₁ and b ₂ described above.
Therefore, the cleaning member 10 does not clean the place of the charging member 9 where the abrasion powder and the toner passing therethrough adhere and accumulate, and the same operation as described above is performed.

As described above, according to the image forming apparatus 1 of this embodiment, the toner leaking through the gaps a ₁ and a ₂ at both ends of the cleaning member 18 and the developing members 13a, 14a, 15a, 1
The charging member outside the cleaning area by the cleaning member 10 removes toner leaking through the gaps b ₁ and b ₂ at both ends of the OPC 2, abrasion powder of the photosensitive layer of the OPC 2 that is worn by contact with the developing device, and toner that slips from the abraded portion of the OPC 2. 9 to accumulate
Since these toners are not cleaned by the cleaning member 10, uneven distribution of accumulated toner and abrasion powder in the cleaning member 10 can be eliminated. Therefore, it is possible to prevent a rapid decrease in the ability of the cleaning member 10 to remove foreign substances, and to prevent saturation at an early stage. Accordingly, the life of the cleaning member 10 can be prolonged, and foreign matter removal of the charging member 9 by the cleaning member 10 can be effectively performed over a long period of time. Therefore, occurrence of OPC charging failure by the charging member 9 can be reduced.

Then, since the uneven distribution of the accumulated toner and the accumulated wear powder in the cleaning member 10 is eliminated, the cleaning member 1 is removed.
Thus, the accumulated toner capacity of the cleaning member 10 defined by the shape and size of 0 can be maximized. Thereby, in realizing the same life of the cleaning member 10, the cleaning member 10 can be downsized,
The size and cost of the device can be reduced.

Further, since the accumulated toner is not unevenly distributed, the amount of the accumulated toner in the cleaning member 10 can be increased, and the life of the charging member 9 and the cleaning member 10 can be prolonged.
Since the replacement period of the consumable parts can be extended, special effects such as reduction of running cost and elimination of complicated user maintenance can be obtained.

In the above-described example, each developing member 13a,
Although the width γ of 14a, 15a, 16a is also specified, the present invention is not limited to this, and the width γ is not particularly specified, and the width α of the charging member 9 ≧ the width β of the cleaning member 18> The width δ of the cleaning member 10 can be set to be greater than the width ε of the image area on the OPC2, whereby the above-described operation and effect can be obtained with respect to toner leakage from the gaps a ₁ and a ₂ at both ends of the cleaning member 18. .

Further, in the above-described example, the present invention
However, the present invention is not limited to this, and an image including a charging member for charging the photoconductor and a cleaning member for cleaning the charging member is described. The present invention can be applied to any image forming apparatus as long as it is a forming apparatus.

[0035]

As is apparent from the above description, according to the image forming apparatus of the present invention, the uneven distribution of the toner leaking toward the charging member from the gaps at both ends of the cleaning member is eliminated. As a result, it is possible to prevent the foreign matter removing ability of the cleaning member from rapidly decreasing and saturating relatively quickly, thereby extending the life of the cleaning member. This makes it possible to effectively remove foreign matters from the charging member by the cleaning member over a long period of time, and to reduce the occurrence of poor charging in the image area of the photoconductor.

Further, since the uneven distribution of the accumulated toner amount in the cleaning member is eliminated, the accumulated toner capacity of the cleaning member defined by the shape and size of the cleaning member can be utilized to the maximum. This makes it possible to reduce the size of the cleaning member to achieve the same life of the cleaning member, thereby achieving a reduction in size and cost of the apparatus. Furthermore,
By increasing the amount of toner accumulated in the cleaning member and extending the life of the charging member and the cleaning member, the replacement period of consumable parts can be extended, thereby reducing running costs and eliminating the complexity of user maintenance. A special effect, such as the ability to perform, can also be obtained.

In addition to the above, according to the invention of claim 2,
Since the uneven distribution of the toner leaking from the gaps at both ends of the developing member into the cleaning member is also eliminated, it is possible to prevent the foreign matter removing ability of the cleaning member from decreasing more rapidly and to prevent the cleaning member from saturating relatively quickly, and Can be further extended. This makes it possible to more effectively remove foreign matter from the charging member by the cleaning member over a long period of time, and to further reduce the occurrence of charging failure in the image area of the photoconductor.

Further, the abrasion powder of the photosensitive layer of the photoreceptor, which is worn by contact with the end of each developing member, and the toner that slips through the abraded portion are the same as the case of the toner leaking from the gaps at both ends of the developing member. Since the uneven distribution of the toner in the cleaning member is also eliminated, the life of the cleaning member can be further extended, and the foreign matter on the charging member can be more effectively removed by the cleaning member for a long period of time. The occurrence of charging failure in the image area can be further reduced.

[Brief description of the drawings]

FIG. 1 is a diagram schematically showing a full-color intermediate transfer type image forming apparatus to which an example of an embodiment of the image forming apparatus of the present invention is applied.

FIG. 2 is a diagram illustrating a magnitude relationship among respective widths of a charging member, a developing member, a cleaning member, and a cleaning member used in the image forming apparatus of the example illustrated in FIG.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Image forming apparatus, 2 ... Photoconductor (OPC), 3 ... Charging device, 5 ... Developing device, 7 ... Cleaning device, 8 ... Housing, 9 ... Charging member, 10 ... Cleaning member, 11 ... Holding member, 12 ... Spring, 13, 14, 15, 16: developing device, 13a, 14a, 15a, 16a: developing member, 18:
Cleaning member, 19, 20, 21, 22 ... sealing _{member, a 1, a 2, b} 1, b 2 ... clearance

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 2H003 AA12 BB11 CC05 2H034 BF01 2H071 DA06 DA08 DA13 EA18 2H077 AD02 AD06 GA03 GA13

Claims (2)

[Claims] 1. A photosensitive member on which an electrostatic latent image is formed, a charging device for charging the photosensitive member while rotating while being in contact with the photosensitive member, and a developing device for developing the electrostatic latent image on the photosensitive member And a cleaning device that cleans the photoconductor after transfer of the developed image on the photoconductor, and a cleaning member that is provided so as to be detachable from the charging member and cleans the charging member. In the image forming apparatus, an image area on the photoconductor on which an image is formed, a charging member of the charging device, a cleaning member of the cleaning device, and a width of the cleaning member are respectively: width of the charging member ≧ cleaning Member width> Cleaning member width>
An image forming apparatus, wherein the width is set to the width of an image area on a photoconductor. 2. The developing device according to claim 1, wherein the width of the developing member is such that: width of charging member ≧ width of cleaning member> width of developing member>
2. The image forming apparatus according to claim 1, wherein the width of the cleaning member is set to be greater than the width of the image area on the photosensitive member.