JP2002023585A - Cleaning device and image forming device provided with the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a cleaning device which enables retaining excellent cleaning performance over a long period and an image forming device equipped with the cleaning device. SOLUTION: This cleaning device is provided with a rotational brush member which slidingly rubs the surface of rotating image carrier on the prescribed position of slidingly rubbing and a blade member which is brought into pressurized contact with the rotating image carrier on the prescribed position of pressurized contact, and removes foreign matter in the region to be cleaned which is a part of the surface of the image carrier. Therein, the position of pressurized contact exists on the downstream side of the rotation direction of the image carrier in the region to be cleaned than the position of the slidingly rubbing and the position of the pressurized contact exists downward in the gravitational direction than the position of the slidingly rubbing.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cleaning device for an electrophotographic image forming apparatus such as a copying machine, a printer, a facsimile machine, and a multifunction peripheral thereof.

[0002]

2. Description of the Related Art Conventionally, in an image forming apparatus such as a copying machine using an electrophotographic process, a cleaning device is widely used to remove foreign matters such as toner adhered to the surface of a rotating image carrier. ing. For example, JP-A-5-313512, JP-A-10-69146
In this publication, an inlet seal, a brush member, and a blade member are sequentially arranged from the upstream side to the downstream side in the rotation direction of a partial region of the surface of the image carrier, and the blade member exists above the brush member in the direction of gravity. A cleaning device is disclosed.

[0003]

However, Japanese Patent Application Laid-Open No. 5-3
In the technology disclosed in JP-A-135512 and JP-A-10-69146, toner or the like scraped off by the blade member accumulates over time on the blade edge portion, and when the accumulation reaches a certain amount or more, the brush member is overheated. To clean the brush member and impair the cleaning performance.

[0004] The present invention has been made in view of such problems, and an object of the present invention is to provide a cleaning apparatus capable of maintaining good cleaning performance for a long period of time and an image forming apparatus provided with the cleaning apparatus. To provide.

[0005]

According to the present invention, there is provided a rotating brush member which rubs a rotating image carrier surface at a predetermined rubbing position, and a blade which presses the rotating image carrier surface at a predetermined pressing position. A cleaning device for removing foreign matter in a region to be cleaned, which is a part of the surface of the image carrier, wherein the pressure contact position is located downstream of the rubbing position in the rotation direction of the image carrier in the region to be cleaned. And the pressure contact position exists below the rubbing position in the direction of gravity (claim 1).

FIG. 1 is a conceptual diagram illustrating the basic configuration of the present invention. As shown in FIG.
It rotates in the direction shown by. The rotating brush member rubs the surface of the image carrier at a predetermined position (sliding position) on the surface of the image carrier, and the blade member moves at a predetermined position (pressure contact position) downstream in the rotation direction from the rubbing position. It is in pressure contact with the surface of the image carrier. Further, the pressure contact position exists below the sliding position in the direction of gravity. Here, the press-contact position may be located below the rubbing position in the direction of gravity, that is, in a region below the horizontal plane including the rubbing position in the direction of gravity, and the press-contact position is necessarily located immediately below the rubbing position. No need. Note that a part of the surface of the image carrier including the rubbing position and the pressing position is a region to be cleaned.

In such a cleaning device, foreign matter adhering to the surface of the image carrier reaches the area to be cleaned along with the rotation of the image carrier, and is rubbed by a rotating brush member at a rubbing position, and then at a pressing position. It is blocked by the blade member and does not move downstream of the area to be cleaned, and exhibits a cleaning effect. Here, in the cleaning device according to the present invention, even if foreign matter caught by the blade member accumulates over time, the foreign matter does not fall on the rotating brush member and contaminate it, so that good cleaning performance can be obtained for a long period of time. Can be demonstrated.

In the rubbing position, the rotation direction of the image carrier and the rotation direction of the rotating brush member may be the same (see arrow C in the figure), but may be opposite to each other (arrow B in the figure).
Is preferable from the viewpoint of cleaning properties (claim 2). This is because if the rotating directions are opposite to each other (see arrow B in the drawing), the foreign matter flies upstream in the rotational direction from the rubbing position due to the rubbing of the rotating brush member, and flows downstream from the rubbing position. This is because foreign substances are less likely to adhere again to the area to be cleaned.

The foreign matter to be cleaned generally contains toner and paper dust, and the toner is charged positively or negatively. Therefore, the present invention
The foreign matter may include a charged toner, the rotating brush member may include a conductive brush, and a bias voltage having a polarity opposite to the polarity of the toner may be applied to the conductive brush. With such a configuration of the cleaning device, an electrostatic attraction is generated between the toner and the conductive brush, so that the foreign matter (toner) can be more effectively removed.

[0010] In general, the smaller the particle size of the toner is, the higher the quality of the toner image can be obtained. On the other hand, when the toner adheres to the image carrier, it is difficult to clean. Therefore, by employing the cleaning device according to the present invention, the cleaning performance can be improved, and as a result, a toner having a smaller particle size can be used without sacrificing the cleaning performance, and a high-quality image can be obtained. Can be obtained. That is, the foreign matter can include a toner having a small particle size (a volume average particle size is 3 to 7 [μm]).

In the above-mentioned blade member, a part other than a part which is in pressure contact with the surface of the image carrier may be made conductive and electrically grounded. With this configuration of the cleaning device, it is possible to prevent the charged toner from adhering to the blade member.

The image bearing member includes a photosensitive member, an intermediate transfer member, a sheet conveying member, and the like, and may have a drum shape or an endless belt shape. In the case of an endless belt, the image carrier is an endless belt stretched by a plurality of rolls, and the rubbing position and the pressing position are opposed to one of the plurality of rolls. Item 6) can be adopted. By configuring the cleaning device in this manner, the one roll can be used not only as a tension roll of the endless belt but also as a counter roll of the rotating brush member and the blade member, thereby reducing the total number of parts. And cost can be reduced.

The one roll may be a steering roll for controlling the movement of the endless belt in the width direction (claim 7). In this case, the rotation of the rotating brush member or the blade member is changed according to the change in the attitude of the steering roll. It is preferable to provide an interlocking mechanism for changing the posture (claim 8).
With this configuration of the cleaning device, the relative positional relationship between the steering roll, the rotating brush member (sliding position), and the blade member (pressing position) is maintained during the steering operation of the steering roll. Further, the steering roll may be a steering drive roll having a drive function of driving an endless belt (image carrier).

These cleaning devices include a housing that covers the area to be cleaned and has the rotating brush member and the blade member disposed therein, and a seal that seals the housing and the surface of the image carrier at the upstream end of the area to be cleaned. The blade member may seal the housing and the surface of the image carrier at the downstream end of the area to be cleaned. Further, the present invention is also an image forming apparatus provided with these cleaning devices.

[0015]

[Embodiment] FIG. 2 and FIG.
1 shows a tandem type color image forming apparatus using an intermediate transfer belt according to an embodiment of the present invention.

The color image forming apparatus includes an intermediate transfer belt (image carrier) 1, a steering drive roll (steering member of an active steering device) 2 for supporting the intermediate transfer belt 1, a tension roll 3,
And a secondary transfer backup roll 4, a yellow image forming unit 5, a magenta image forming unit 6, which is disposed between the steering drive roll 2 and the tension roll 3 so as to face the intermediate transfer belt 1. The image forming unit 7 for cyan and the image forming unit 8 for black, the belt cleaning unit 9 disposed in the vicinity of the steering drive roll 2, and the secondary transfer backup roll 4 are disposed opposite to each other. A secondary transfer device 10 having a secondary transfer roll 10a, and a ROS (Raser Output Scanner) unit for writing an electrostatic latent image on each of the photosensitive drums 5a to 8a of the image forming units 5 to 8
11, a paper tray unit 12, and a fixing unit 13. The steering drive roll 2 is formed of an aluminum bar, and has a surface roughness of Ra 1.
6 is formed.

The intermediate transfer belt 1 is prepared by dispersing an appropriate amount of a conductive agent such as carbon black in a synthetic resin such as polyimide, polycarbonate, polyester, or polypropylene, or various rubbers, and having a volume resistivity of 10 ⁶ to 10 ^14. Ω
-It is composed of a film-shaped belt adjusted to be cm. The thickness of the intermediate transfer belt 1 is set to, for example, 0.1 mm. Further, the intermediate transfer belt 1 has a Young's modulus of 370 kgf / mm ² and a surface roughness Ra of 6.0.

Here, each of the image forming units 5 to 8 is
The developing devices 5b to 8b corresponding to the respective colors are provided adjacent to the photosensitive drums 5a to 8a, and the developing devices 5b to 8b are provided with toner cartridges 14 to 8 corresponding to the respective colors by toner supply means (not shown). From 17, toner of each color is supplied. In the drawings, reference numerals 18 to 21 denote backup rolls for primary transfer arranged so as to face the photosensitive drums 5a to 8a of the image forming units 5 to 8, respectively.

Here, the volume average particle size and the particle size distribution of the toner particles of each color are substantially the same, and the volume average particle size measured with a Coulter counter (manufactured by Coulter Co.) is 3 to 7 μm.
m and the particle size distribution index (GSD) was 1.23. The toner particles used had an average shape factor of 125 or less. Here, the shape factor refers to a magnified photograph of toner particles obtained by an optical microscope (Microphoto FXA: manufactured by Nikon Corporation) taken by an image analyzer Luzex.
3 (manufactured by NIRECO), image analysis was performed, and the shape factor = ((absolute maximum length of toner diameter) ² × (π / 4) × 10
0) / (projected area of toner).

That is, the toner shape factor is expressed by the ratio of the projected area of the toner to the area of a circle circumscribing the projected area.
The value is 100 in the case of a true sphere, and the value increases as the shape of the toner particles collapses. An appropriate amount of inorganic fine particles (external additives) such as silica and titania having an average particle diameter of 10 to 150 nm is externally added to the toner, and the average particle diameter is 35 μm.
m was mixed with a carrier made of ferrite beads to obtain a developer.

In the color image forming apparatus of the first embodiment, the single-color toner images formed by the image forming units 5 to 8 are superposed on the intermediate transfer belt 1 to form a multicolor toner image. The toner image moves to the secondary transfer device 10, where the paper route P
As shown in (1), the image is secondarily transferred onto the sheet supplied from the sheet tray unit 12, and then discharged to the outside of the apparatus via the fixing unit 13.

As shown in FIG. 4, the belt cleaning unit (cleaning device) 9 used in the first embodiment is provided within an overlap area where the intermediate transfer belt 1 is wound around the steering drive roll 2. In the casing 9a, a predetermined position (sliding position) P on the surface of the intermediate transfer belt 1 is set.
_{In 2} , the rotating brush (rotating brush member) 9 c rubs the surface of the intermediate transfer belt, and the cleaning blade (blade member) 9 b moves at a predetermined position (pressure contact position) P ₃ in the rotation direction downstream of the rubbing position P _2. It is in pressure contact with the intermediate transfer belt 1. Further, the contact position P ₃ is present in the direction of gravity below the scraping position P _2.

[0023] Then, the cleaning blade 9b in contact position P ₃ is also the upper sealing 9e at a predetermined position P ₁ has a seal between the casing 9a respectively with the intermediate transfer belt 1. Cleaning unit 9
An auger 9d is provided at the bottom of the casing 9a. Incidentally, the region of the intermediate transfer belt surface surrounded by these position P ₁ and the pressure-contact position P ₃ is set to be cleaned region.

Further, in the rubbing position P _2, the rotation direction of the intermediate transfer belt 1 (in the arrow A) to the rotating direction of the rotating brush 9c (in the arrow B) are opposite to each other. The brush portion of the rotating brush 9c is made of a conductive member of nylon and carbon, has a diameter of about 20 mm, and a portion overlapping the intermediate transfer belt 1 is set at about 1.5 mm. A bias voltage is applied to the rotating brush 9c. The polarity of the bias voltage is such that a voltage having a polarity opposite to the charge polarity of the toner attached to the intermediate transfer belt 1 is applied. In the present embodiment, a voltage of plus 400 V is applied to the rotating brush 9c. I have.
The steering drive roll 2 is electrically grounded.

Furthermore, the rotary brush 9c is configured to rub the de-toning rolls 9f at a position substantially opposite to the rubbing position P _2. Detoning roll 9
f is a pipe-shaped member having a diameter of about 18 mm that has been anodized, to which a bias voltage has been applied. The polarity of the bias voltage is such that a voltage having a polarity opposite to that of the toner charged on the intermediate transfer belt 1 is applied, and the absolute value of the voltage is larger than the absolute value of the voltage applied to the rotating brush 9c. Applied. In the present embodiment, a voltage of plus 800 V is applied to the detoning roll 9f. The distortion roll 9f is configured to rotate in a direction opposite to that of the rotating brush 9c, and a portion overlapping the rotating brush 9c is set to about 1.0 mm. Note that a blade 9g for scraping off the toner and the like on the surface of the distortion roll 9f is in pressure contact with the distortion roll 9f.

FIG. 5 illustrates the structure of the cleaning blade 9b of the cleaning unit 9 shown in FIG. 4 in more detail. This cleaning blade 9b
It is pressed against the surface of the intermediate transfer belt 1 in a so-called doctor direction. This cleaning blade 9b
An elastic blade body 90b made of polyurethane;
A sheet metal 92b made of stainless steel or aluminum and supporting the blade body 90b;
0b, the conductive paint 91b is applied and hardened to a portion other than the portion that comes into pressure contact with the intermediate transfer belt 1. The cleaning blade 9b is set at a blade setting angle (Bl
ade Set Angle; BSA) 22 °, blade penetration 1.
It is set to 1 mm. The conductive paint 91b is in contact with the sheet metal 92b, and the sheet metal 92b is electrically grounded.

The application of the conductive paint 91b is performed, for example,
This is performed in a state where a portion of the blade main body 90b that comes into pressure contact with the intermediate transfer belt 1 is masked. As the conductive paint 91b, for example, Dotite (trade name) manufactured by Fujikura Kasei Co., Ltd., which is a silver paste paint, is used. The thickness of the conductive paint 91b is set, for example, to 50 μm or less, and the resistance value is set to 10 ⁵ Ω or less, and preferably to 10 ³ to 10 ⁴ Ω or less. As the conductive paint 91b, a paint that does not affect the basic characteristics (elasticity and the like) of the blade body 90b is employed.

The conductive treatment is not limited to applying and curing such a conductive paint 91b. For example, a conductive sheet may be adhered to the blade 90b body,
A metal such as aluminum may be deposited on the blade 90b body.

Next, such a cleaning unit 9
Will be described. Foreign matter adhering to the surface of the intermediate transfer belt 1 reaches the overlap region with the rotation of the intermediate transfer belt 1, and further passes through the upper seal 9e to reach the region to be cleaned. When reaching the rubbing position P2, a part of the foreign matter is scattered by the rotation of the rotating brush 9c.

At this time, the toner in the foreign matter adhering to the intermediate transfer belt 1 is negatively charged in many cases in this embodiment. On the other hand, a voltage of plus 400 V is applied to the rotating brush 9c as described above. Therefore, the foreign matter (toner) on the intermediate transfer belt 1 is more easily cleaned by the electrostatic force due to the electric field in addition to the physical force due to the rubbing. The rotating brush 9c
Foreign matter flying by the rotation of the cleaning blade 9
Since it flies in the opposite direction to b, the cleaning blade 9b is not excessively soiled.

In particular, in this embodiment, the rotating brush 9c is configured to rub against the rotating detoning roll 9f, and the detoning roll 9f has an additional 800.
Since the voltage of V is applied, the foreign matter (toner) adhering to the rotating brush 9c without flying is attracted to the distortion roll 9f by a more electrostatic force and adheres thereto, so that the rotating brush 9c 9c is not stored. The foreign matter (toner) attached to the distortion roll 9f is finally scraped off by the blade 9g. As a result, aggregates of foreign substances do not fall from the rotating brush 9c to the cleaning blade 9b below in the direction of gravity.

[0032] were not scattered by the rotating brush 9c foreign body reaches the contact position P ₃ along with rotation of the intermediate transfer belt 1 is held by a cleaning blade 9b. When the foreign matter held by the cleaning blade 9b exceeds a certain amount, the foreign matter falls from the edge of the cleaning blade 9b, and is finally conveyed to the outside of the cleaning unit 9 by the auger 9d and discarded. Also,
The same applies to foreign substances scraped off by the blade 9g.
At this time, with the direction of gravity positional relationship between the rubbing position P ₂ and the pressure-contact position P _3, the foreign matter falling from the edge portion of the cleaning blade 9b is unlikely be dirty rotating brush 9c.

Next, in this embodiment, FIGS.
As shown in FIG. 8, a movable frame 22 that rotatably supports the steering drive roll 2 is disposed on a block main 1b that forms the transfer body frame 1a of the intermediate transfer belt 1. The casing 9a of the belt cleaning unit 9 is detachably attached to the movable frame 22.

The movable frame 22 has a block main 22a located opposite to the block main 1b on the transfer body frame 1a side, and an inner frame 22b and an outer frame 22c attached to both ends of the block main 22a. The steering drive roll 2 is rotatably supported between the inner frame 22b and the outer frame 22c of the movable frame 22.

The transfer frame 1a of the intermediate transfer belt 1
A pivot 23 is fixed to the block main 22a of the movable frame 22 between the block main 1b and the block main 22a of the movable frame 22 near the inner side in the belt width direction of the intermediate transfer belt 1 (upper side in FIG. 6). The leading end of the pivot 23 is the block main of the transfer body frame 1a.
The movable frame 22 is rotatably fitted in a through hole 24 formed on the 1b side, so that the outside of the movable frame 22 can be displaced in the vertical direction about the pivot 23 as a rotation axis. FIG.
FIGS. 6 and 8 are cross-sectional explanatory views showing a pivot 23 attached between a block main 1b forming a transfer body frame 1a and a block main 22a of a movable frame 22.

As shown in FIG. 6, FIG. 7, and FIG. 8, the block main 1b side of the transfer body frame 1a near the outer side in the belt width direction of the intermediate transfer belt 1 (the lower side in FIG. 6). A roller 25 is attached to the block 23, and the block main 1b of the transfer body frame 1a and the block main 22a of the movable frame 22 are accurately arranged in parallel with each other while maintaining a predetermined distance d by the pivot 23 and the roller 25. ing. FIG. 10 is an explanatory cross-sectional view showing the roller 25 attached to the block main 1b side of the transfer body frame 1a in FIG. FIG. 11 shows VIII-VI of FIG.
FIG. 2 is a sectional view taken along line II.

A steering cam 26 is provided below the outer frame 22c constituting the movable frame 22, and the outer frame 22c of the movable frame 22 is placed above the steering cam 26. The steering cam 26 is driven by a steering motor 27 that is controlled by a signal from a sensor (not shown) that detects the meandering phenomenon of the intermediate transfer belt 1.

Accordingly, in this embodiment, when the meandering phenomenon occurs in the intermediate transfer belt 1, the steering motor 27 rotates in a predetermined direction by a predetermined amount in response to a signal from a sensor detecting the meandering of the intermediate transfer belt 1. The movable frame 22 is displaced up and down on the outer frame 22c side with the pivot 23 as a rotation axis, so that the steering drive roll 2 attached to the movable frame 22 is moved.
Changes its posture for its steering action,
The cleaning blade 9b and the rotating brush 9c of the belt cleaning unit 9 attached to the movable frame 22
Also changes the posture in accordance with the change in posture caused by the steering operation of the steering / drive roll 2, and changes the steering / drive roll 2 and the cleaning blade 9.
b, the relative positional relationship with the rotating brush 9c is maintained.

In this embodiment, as shown in FIG. 8, between the outside of the transfer body frame 1a and the outside frame 22c of the movable frame 22, the block main 1b of the transfer body frame 1a and the block main of the movable frame 22 are moved. A tension spring 28 is provided for urging the outer frame 22c of the movable frame 22 toward the steering cam 26, thereby urging the outer frame 22c of the movable frame 22 toward the steering cam 26. The parallelism between the block main 1b of the movable frame 22 and the block main 22a of the movable frame 22 is not impaired, and the movement of the steering cam 26 is accurately transmitted to the movable frame 22 without play.

In this embodiment, as shown in FIGS. 6 and 8, between the belt cleaning unit 9 and the movable frame 22, a pin 99 provided on the belt cleaning unit 9 side is movable. It is positioned by a pin hole 22e provided in an inner frame 22b of the frame 22.
Between the inner frame 22b and the outer frame 22c, the inner frame 22b and the outer frame 22c and the rear frame 22d.
And between the casing 9a of the belt cleaning unit 9 and the outer frame 22c of the movable frame 22 are fixed by mounting screws 29.

Accordingly, the belt cleaning unit 9
As shown in FIG. 8, the mounting frame 29 can be easily removed from the movable frame 22 by removing the mounting screws 29 connecting the casing 9a to the rear frame 22d and the outer frame 22c of the movable frame 22. When the amount of toner collected from the surface of the intermediate transfer belt 1 by the cleaning blade 9b and sent to a toner collection box (not shown) via the auger 9d reaches a predetermined amount, the belt cleaning unit 9 can be replaced.

In the belt cleaning unit 9, a toner collecting box may be detachably mounted, and only the toner collecting box may be removed so that the collected toner can be discarded.

When a test operation of the color image forming apparatus of this embodiment was performed with such set values,
Even during the steering operation by the drive roll 2, the intermediate transfer belt 1 does not slip in the belt rotation direction,
Also, no cleaning failure was observed.

Further, in this embodiment, the pivot 23 and the roller 25 are used to move the block main 1b of the transfer body frame 1a.
The distance d between the movable frame 22 and the block main 22a
Is maintained so that the parallelism between the two is obtained. However, instead of the roller 25, as shown in FIG. 12, the block main 22a of the movable frame 22 (or the block main 1b of the transfer body frame 1a) is used. A spacer 32 made of resin or the like having excellent slipperiness may be provided on the side of ()).

Further, in this embodiment, a conductive brush is used as the rotating brush 9c and is electrically grounded. However, an insulating brush (a so-called disturber brush) may be used. . At this time, the insulating brush may collide with the flicker bar as it rotates, and the foreign matter attached by the impact of the collision may be shaken off.

Test Example In order to confirm the effect of the present invention, the present inventors conducted the following cleaning test using a comparative example. First, as the cleaning unit 9,
As shown in FIG. 13A as Comparative Example 1, the relationship between the pressure contact position P3 and the rubbing position P2 in the direction of gravity is different from that of the embodiment, and the intermediate transfer belt at the rubbing position P2 is used. As shown in FIG. 13B, the relationship between the pressing position P3 and the rubbing position P2 in the direction of gravity is different from that of the embodiment, as shown in FIG. (The rotation of the intermediate transfer belt 1 and the rotating brush 9c in the rotation direction at the rubbing position P2 is the same as that of the embodiment).

The three types of cleaning units 9 were used over time under the same conditions, and the cleaning performance and the state inside the casing 9a at that time were observed, evaluated, and examined. The cleaning apparatus was used under a low-temperature, low-humidity environment (temperature: 10 degrees Celsius, humidity: 15 percent), which is a condition that is generally difficult to clean. The results are as follows.

Comparative Example 1 Although the cleaning property was good in the initial state,
Insufficient cleaning occurred after about 10,000 images were formed. When the inside of the cleaner unit 9 was examined, it was found that the rotating brush 9c was contaminated, and that the ability of the intermediate transfer belt 1 to scrape off the toner was reduced due to the contamination. The cause of the contamination of the rotating brush 9c is as follows.
Since the toner scraped off by the cleaning blade 9b falls on the rotating brush 9c and promotes dirt, and since the rotating direction of the rotating brush 9c is on the cleaning blade 9b side, the flying toner re-adheres to the area to be cleaned. It is mentioned that.

Comparative Example Cleanability was good both in the initial state and after the formation of about 10,000 images. This is comparative example 1.
This is presumably because the above-mentioned elements do not exist. On the other hand, since the rotating direction of the rotating brush 9c is on the side of the seal 9e, a phenomenon that the target toner is deposited around the seal 9e and a part of the toner passes through the seal 9e and drops into the machine or paper is confirmed.

Example In the initial state, after forming about 10,000 sheets of images, of course,
Even after about 100,000 sheets of images were formed, the cleaning property was good. Also, the casing 9 of the cleaner unit 9
Also, it was not confirmed that the toner dropped from a in the machine or on paper.

[0051]

As described above in detail, according to the present invention, there is provided a cleaning device capable of maintaining good cleaning performance for a long period of time and preventing foreign substances from leaking from the cleaner device. can do.

[Brief description of the drawings]

FIG. 1 is a conceptual diagram showing a basic configuration of the present invention.

FIG. 2 is a schematic cross-sectional view of the image forming apparatus according to the embodiment.

FIG. 3 is a schematic sectional view illustrating a peripheral configuration of an intermediate transfer belt of the image forming apparatus shown in FIG. 2;

FIG. 4 is a schematic sectional view of a cleaning unit according to the embodiment.

FIG. 5 illustrates the cleaning blade of the cleaning unit shown in FIG. 4 in more detail.

FIG. 6 shows a cleaning unit disposed near a steering drive roll.

FIG. 7 is a sectional view taken along line IV-IV of FIG. 6;

FIG. 8 is an exploded view of the part shown in FIG. 6;

9 is an explanatory cross-sectional view showing a pivot attached between a block main of a movable frame and a block main of a transfer frame in FIG. 8;

FIG. 10 is an explanatory cross-sectional view showing a roller attached to a block main of the transfer frame in FIG. 8;

FIG. 11 is an explanatory cross-sectional view taken along line VIII-VIII of FIG. 10;

FIG. 12 is an explanatory cross-sectional view showing a spacer attached in place of the roller of FIG. 10;

FIG. 13 is a schematic cross-sectional view illustrating a configuration of a cleaning unit according to a comparative example.

[Explanation of symbols]

1. Intermediate transfer belt (image carrier) 2. Steering
Drive roll (one roll), 9 cleaning unit, 9a casing, 9b cleaning blade (blade member), 9c rotating brush (rotating brush member), 9d auger, 9e upper seal

 ──────────────────────────────────────────────────の Continuing on the front page (72) Nobuo Hyakutake 2274 Hongo, Ebina-shi, Kanagawa Prefecture, F-term in Fuji Xerox Co., Ltd. Ebina Works (reference) 2H034 AA06 BA01 BA02 BA03 BD04 BD06 BD07 BD09 BF04 BF05 BF06

Claims (10)

[Claims] A rotating brush member that rubs the rotating image carrier surface at a predetermined rubbing position; and a blade member that presses the rotating image carrier surface at a predetermined pressing position. In the cleaning device for removing foreign matter in a cleaning region which is a part of the surface, the pressure contact position is located downstream of the cleaning region in the image carrier rotation direction with respect to the rubbing position, and the pressure contact position is The cleaning device is located below the rubbing position in the direction of gravity. 2. The cleaning device according to claim 1, wherein in the rubbing position, the rotation direction of the image carrier and the rotation direction of the rotary brush member are opposite to each other. 3. The method according to claim 1, wherein the foreign matter includes charged toner, the rotating brush member includes a conductive brush, and a bias voltage having a polarity opposite to the polarity of the toner is applied to the conductive brush. 3. The cleaning device according to 2. 4. The foreign matter has a volume average particle size of 3 to 7 μm.
The cleaning device according to any one of claims 1 to 3, further comprising: 5. The cleaning device according to claim 1, wherein a portion of the blade member other than a portion that is in pressure contact with the surface of the image carrier is subjected to a conductive treatment and is electrically grounded. 6. The image bearing member is an endless belt stretched by a plurality of rolls, and the rubbing position and the pressing position are opposed to one of the plurality of rolls. The cleaning device according to any one of the above. 7. The cleaning device according to claim 6, wherein the one roll is a steering roll for controlling movement of the endless belt in a width direction. 8. The cleaning device according to claim 7, further comprising an interlocking mechanism that changes the positions of the rotating brush member and the blade member in accordance with the change in the position of the steering roll. 9. A housing for covering the area to be cleaned and disposing the rotating brush member and the blade member therein, and a seal member for sealing the housing and the surface of the image carrier at an upstream end of the area to be cleaned. ,
9. The cleaning device according to claim 1, wherein the blade member seals the housing and the surface of the image carrier at a downstream end of the area to be cleaned. 10. An image forming apparatus comprising the cleaning device according to claim 1.