JP2004109495A - Cleaning device and image forming apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a cleaning device which prevents partial soil on a brush roller and ensures, for a long time, satisfactory cleaning of a member to be cleaned and to provide an image forming apparatus having the cleaning device. <P>SOLUTION: The cleaning device has a brush roller 20 having a brush which abuts on the member 110 to be cleaned. In the cleaning device, the brush roller 20 is swung in its axial direction G. In such a structure, even if the member to be cleaned is soiled with foreign matter such as residual toner or paper powder on axial part of the brush roller 20, the foreign matter sticking to the brush roller 20 is distributed in its axial direction. As a result, the brush roller 20 is prevented from being soiled partly, and the cleaning capability of the brush roller 20 is maintained. Soil on the member to be cleaned is satisfactorily removed over time. Thus, satisfactory removal of soil on the member to be cleaned is ensured for a long time. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a cleaning device provided in an image forming apparatus such as a copying machine, a facsimile, a printer, and the like, for cleaning dirt such as toner adhered to members provided in the image forming apparatus, and an image forming apparatus having the same.
[0002]
[Prior art]
2. Description of the Related Art In an image forming apparatus such as a copying machine, a printer, a facsimile, or the like, a toner image is carried on a sheet-shaped recording medium by an image forming process mechanism such as an electrophotographic method. Such an image forming process mechanism forms a toner image carried on a recording medium on an image carrier such as a photoreceptor. Conventionally, an image carrier, which performs such a toner image forming step, A cleaning device that cleans the surface of a charging roller, a transfer belt, or the like is used. The cleaning device is for removing dirt such as toner and paper dust adhered to the member to be cleaned such as the image carrier.
[0003]
As such a cleaning device, a device provided with a brush roller that comes into contact with the surface of a member to be cleaned is known as disclosed in [Patent Document 1] and [Patent Document 2]. This type of conventional cleaning device rotates a brush roller by a driving device, and applies a difference between a linear velocity of the brush contacting the surface of the member to be cleaned and a linear speed of the surface of the member to be cleaned, so that the surface of the member is cleaned. This is to remove the adhered foreign matter and clean the surface.
[0004]
In addition, the applicant has previously filed an application for a cleaning device provided with a brush roller having a brush fiber length of 2 mm or less, but the technique according to this application uses the brush roller and the member to be cleaned as described above. The cleaning is performed by suppressing the elastic deformation of the brush, making the tip end surface of the brush fiber abut against the surface of the member to be cleaned, and ejecting the foreign matter on the surface instead of performing the cleaning by the linear velocity difference from the above.
[0005]
However, in such a brush roller that foreign matter attached to the member to be cleaned, mainly toner and paper dust, is blown out of the member to be cleaned at the tip end surface of the brush fiber, the foreign matter that has been blown out gradually accumulates mainly in the brush fiber. As the accumulation of foreign matter in the brush increases, the cleaning ability decreases.
[0006]
[Patent Document 1]
JP-A-6-95570 [Patent Document 2]
JP-A-7-140763
[Problems to be solved by the invention]
In particular, for example, the member to be cleaned is a charging roller, and dirt that has adhered to the image carrier and has not been partially removed adheres to the charging roller, contaminates a portion of the charging roller in the axial direction, and has a streak-like surface on the surface. When dirt occurs, the cleaning brush accumulates dirt at a portion that comes into contact with the streak-like dirt, the cleaning ability of the portion is reduced, and dirt on the member to be cleaned is accelerated at the portion. In addition, there is a problem in that contamination of a specific portion of the brush occurs, and it becomes impossible to remove the corresponding dirt of the specific portion of the member to be cleaned.
[0008]
SUMMARY OF THE INVENTION It is an object of the present invention to provide a cleaning device which prevents local contamination of a brush roller and cleans a member to be cleaned satisfactorily for a long period of time, and an image forming apparatus having the same.
[0009]
[Means for Solving the Problems]
In order to achieve the above object, the invention according to claim 1 is characterized in that in a cleaning device provided with a brush roller having a brush abutting on a member to be cleaned, the brush roller swings in the axial direction thereof.
[0010]
According to a second aspect of the present invention, in the cleaning device according to the first aspect, a swing member that engages with the brush roller and swings the brush roller in an axial direction thereof is provided.
[0011]
According to a third aspect of the present invention, in the cleaning device according to the first or second aspect, the brush roller rotates following a member to be cleaned.
[0012]
The invention according to claim 4 is the cleaning device according to any one of claims 1 to 3, wherein the length of the brush is 2 mm or less.
[0013]
According to a fifth aspect of the present invention, in the cleaning device according to any one of the first to fourth aspects, the thickness of the fiber of the brush is 2 denier or less, and the density of the fiber is 20,000 fibers / cm ² or more. There is a feature.
[0014]
According to a sixth aspect of the present invention, there is provided an image forming apparatus having the cleaning device according to any one of the first to fifth aspects.
[0015]
According to a seventh aspect of the present invention, in the image forming apparatus according to the sixth aspect, a toner produced by a polymerization method is used.
[0016]
According to an eighth aspect of the present invention, in the image forming apparatus according to the sixth or seventh aspect, at least the cleaning device constitutes a process cartridge.
[0017]
【Example】
FIG. 1 schematically shows an image forming apparatus to which the present invention is applied. The image forming apparatus may be any known one such as a copying machine, a facsimile, and a printer, but the image forming apparatus in this embodiment is a printer. Although the image forming apparatus of this embodiment forms a single color image, it may form a color image.
[0018]
The image forming apparatus 100 has a higher heat capacity than plain paper generally used for copying and the like, 90K paper such as OHP sheets, cards, and postcards, thick paper having a basis weight of about 100 g / m ² or more, and envelopes. Any of the large so-called special sheets can be used as a sheet-shaped recording medium for fixing a toner image. The size of the recording medium may be a size conforming to a general standard such as A4 size or A3 size, or may be a size out of the standard formed by cutting or the like.
[0019]
The image forming apparatus 100 is a photoconductive photosensitive drum (hereinafter, referred to as a “photosensitive member”) in which an organic photosensitive material or the like is applied to the surface of a cylindrical image carrier that is driven to rotate in the direction of arrow A. ) 101, a charging roller 110 serving as a charging device as charging means for uniformly charging the photoconductor 101, and a laser beam 103 for forming a latent image corresponding to image information on the photoconductor 101 after charging. And an exposure device (not shown) as an exposure means for performing optical scanning.
[0020]
The image forming apparatus 100 also includes a developing device 104 that is a developing unit as a developing unit that develops a latent image on the photoconductor 101 after exposure, and a static eliminator that neutralizes the developed photoconductor 101 by emitting static electricity 105a. A transfer unit 105 for electrostatically transferring the toner image on the photoconductor 101 obtained by development by the developing device 104 to a sheet (not shown) which is a transfer material as a sheet-shaped recording medium that is brought into close contact with the photoconductor 101 And a registration roller 108 that conveys the sheet at a predetermined timing to a transfer area 107 which is a portion where the photoconductor 101 and the transfer device 109 are opposed to each other.
[0021]
The image forming apparatus 100 also separates the transfer sheet from the photoconductor 101 by a separating claw 111 as a sheet separating unit, and scrapes off the transfer residual toner remaining on the photoconductor 101 after transfer from the photoconductor 101. Accordingly, a cleaning device 106 as a cleaning unit that cleans the photoconductor 101, and a static elimination device 102 as a static elimination unit that emits static elimination light 102 a to the photoconductor 101 before charging by the charging roller 110. And
[0022]
The image forming apparatus 100 also includes a paper feed tray (not shown) on which paper is loaded, a paper feed roller (not shown) serving as paper feeding means for feeding the paper loaded on the paper feed tray toward the registration roller 108, and a transfer device 109. A fixing device (not shown) as a fixing unit for fixing the toner image on the sheet on which the toner image on the photosensitive member 101 is transferred, and a cleaning device 1 for cleaning the charging roller 110 as a member to be cleaned. I have. The sheet after fixing is discharged to the outside of the image forming apparatus 100.
[0023]
The developing roller 104a provided in the developing device 104 rotates in the direction B that moves in the same direction as the direction A at a position facing the photoconductor 101. The cleaning device 106 removes toner and fine paper powder remaining on the surface of the photoconductor 101 by the blade 106a. As the transfer means, a transfer charger, a transfer belt, or the like can be used instead of the transfer roller. The toner used for image formation in the image forming apparatus 100, that is, toner used for development by the developing device 104 is a toner produced by a polymerization method.
[0024]
As shown in FIG. 2, the brush roller 20 constituting the cleaning device 1 and the charging roller 110 with which the brush roller 20 is in contact are rotatable at both ends of their respective shafts 20a, 110a with arm members 11a, 11b, respectively. It is supported by. The arm members 11a and 11b are rotatably supported by shafts 12a and 12b projecting from a process cartridge housing (not shown), respectively. The charging rollers 110 are supported by compression springs 13a and 13b supported by the process cartridge housing. Is contacted to the photoconductor 101. Note that the process cartridge includes at least the cleaning device 1, and in the present embodiment, the cleaning device 1 constitutes a process cartridge together with the charging device 110 and the photoconductor 101.
[0025]
The photosensitive member 101 is driven to rotate in the direction of arrow C in FIG. 2 by gears 14 located at both ends of the photosensitive member 101 by a driving source (not shown), and the charging roller 110 is driven by the photosensitive member 101 by its own weight in the direction of arrow D in FIG. By rotation, the brush 20 rotates in the direction of arrow E in FIG. The gear 14 meshes with a gear 15 as a swing member rotatably supported by the arm member 11a. The gear 15 is driven to rotate in the direction F in the figure by the gear 14. The end of the shaft 20a on the side of the arm member 11a penetrates the arm member 11a and engages with the gear 15 as described later. The gear 15 forms the cleaning device 1.
[0026]
As shown in FIG. 3, a compression spring 16 is wound around one end of the shaft 20a. The compression spring 16 is located between the arm member 11b end surface of the brush roller 20 and the arm member 11b, and urges the brush roller 20 toward the arm member 11a. The compression spring 16 constitutes the cleaning device 1. The other end of the shaft 20a abuts a cam surface 15a protruding from an end surface of the gear 15 on the arm member 11a side. Note that the rotation center of the gear 15 and the axis of the shaft 20a are displaced, and the amount of this displacement matches the rotation radius of the cam surface 15. Accordingly, when the gear 15 rotates in the F direction following the rotation of the photosensitive member 101 in the C direction, the brush roller 20 is rotated by the urging force of the compression spring 16 and the shaft 20a abutting the cam surface 15a. In the G direction, which is the direction, a periodic reciprocating motion of a certain distance is performed to swing.
[0027]
In this embodiment, since the pressing of the brush roller against the charging roller 110, which is the member to be cleaned, is set by the weight of the brush roller 20, a member that regulates the amount of the brush of the brush roller 20 that bites the charging roller 110 is unnecessary. Yes, reducing costs. In addition, the length of the bristle of the brush is reduced to 2 mm or less, the thickness of the brush fiber is 2 denier or less, and the density of the fiber is 20,000 fibers / cm ² or more. The amount of deformation is small and prevents the brush fiber from falling over a long period of time.
[0028]
In this embodiment, when the image formation is started by a predetermined operation, the photosensitive member 101 is driven to rotate, and the photosensitive member 101 is rotated in the direction A by the above-described configuration. The exposure process by the developing device 103, the developing process by the developing device 104, the transferring process by the transfer device 109, the cleaning process by the cleaning device 106, the discharging process by the discharging device 102, and the next image forming cycle in which the charging by the charging roller 110 is performed again .
[0029]
In the process of image formation, it is ideal that the residual toner adhering to the photoreceptor 101 after transfer is completely removed by the cleaning device 106, but a small amount of toner can be removed by the cleaning device 106. Without passing through the blade 106a. The passed toner adheres to the charging roller 110, but the toner on the surface of the charging roller 110 is removed by the cleaning roller 20 that is driven and rotated by the charging roller 110. In addition, paper powder adheres to the photoconductor 101 from the paper contacting the photoconductor 101 during the transfer of the photoconductor 101, and the paper powder similarly adheres and accumulates on the charging roller 110 without being removed by the cleaning device 106. However, the paper dust adhering to the charging roller 110 is also removed by the cleaning roller 20 in the same manner.
[0030]
Even when the charging roller 110 is contaminated by foreign matter such as residual toner and paper dust in a part of the axial direction, the foreign matter adheres to the brush roller 20 because the brush roller 20 swings in the axial direction G. The brush roller 20 is dispersed, and a part of the brush roller 20 is not locally stained, the cleaning ability of the brush roller 20 is maintained, and the stain on the charging roller 110 is well cleaned and removed over time.
[0031]
Since the toner prepared by the polymerization method has an extremely uniform charge-to-charge mass ratio for each particle, the transfer efficiency in the transfer step performed electrostatically can be extremely increased, and the toner remains on the photoconductor 101. The amount of toner is reduced as compared to toner made by other methods. Therefore, the use of the toner produced by the polymerization method also suppresses the adhesion of dirt on the surface of the charging roller 110 due to the residual toner. If the shape of the toner is irregular, the removal efficiency of the cleaning unit 106 is increased as compared to a shape close to a true sphere. Therefore, the toner can be formed so as to have an irregular shape, or the charging roller 110 can be used over time. It is effective to keep it clean.
[0032]
The cleaning device to which the present invention is applied and the image forming apparatus having the same have been described. However, if possible, another member, for example, a photosensitive member may be a member to be cleaned. In this embodiment, not only the cleaning device 1 but also the charging roller 110 whose life is greatly improved by the cleaning device 1 is included in at least the process cartridge, and the cleaning device 1 and the charging roller 110 whose life has been shortened in the past are used for the process. Although the advantage such as good operability of the process cartridge body is utilized while avoiding shortening the life of the entire cartridge, the cleaning device 1 does not necessarily have to constitute the process cartridge.
[0033]
【The invention's effect】
The present invention relates to a cleaning device including a brush roller having a brush abutting on a member to be cleaned, wherein the brush roller oscillates in the axial direction thereof. Even when contaminated with foreign matter such as paper dust, the adhesion of the foreign matter to the brush roller is dispersed in the axial direction, and a part of the brush roller is not locally stained, and the cleaning ability of the brush roller is maintained. In addition, it is possible to provide a cleaning device that can clean and remove dirt on the member to be cleaned with time, and can clean the member for cleaning for a long time.
[0034]
If a swinging member is provided which engages with the brush roller and swings the brush roller in the axial direction, the use of the swinging member allows the member to be cleaned to have residual toner or paper dust in a part of the brush roller in the axial direction. Even when the brush roller is contaminated by foreign matter, the adhesion of the foreign matter to the brush roller is dispersed in the axial direction, a part of the brush roller is not locally stained, and the cleaning ability of the brush roller is maintained, It is possible to provide a cleaning device that can clean and remove dirt on a member to be cleaned with time, and can clean the member for cleaning over a long period of time.
[0035]
If the brush roller rotates in accordance with the member to be cleaned, a member for regulating the amount of the brush of the brush roller that bites into the member to be cleaned is not required, and the structure is relatively simple and the cost can be reduced. A cleaning device that can be provided.
[0036]
If the length of the brush is 2 mm or less, it is possible to provide a cleaning device in which the amount of elastic deformation of the fiber of the brush constituting the brush roller is small and the fiber can be prevented from falling down for a long period of time.
[0037]
If the thickness of the fiber of the brush is 2 denier or less and the density of the fiber is 20000 / cm ² or more, the amount of elastic deformation of the fiber of the brush constituting the brush roller is small, It is possible to provide a cleaning device capable of preventing a fall.
[0038]
Since the present invention resides in an image forming apparatus having the cleaning device according to any one of claims 1 to 5, the image forming apparatus includes a developing cleaning device having each of the above-described effects, and satisfactorily cleans a member to be cleaned for a long period of time. Thus, it is possible to provide an image forming apparatus capable of preventing a member to be cleaned from being contaminated by foreign matter such as residual toner and paper dust for a long period of time and capable of forming a good image over a long period of time.
[0039]
If a toner produced by a polymerization method is used, it is possible to suppress adhesion of dirt due to residual toner to a member to be cleaned, and an image forming apparatus capable of performing good image formation for a long period of time. Can be provided.
[0040]
If at least the cleaning device constitutes the process cartridge, it has advantages such as good operability while avoiding shortening the life of the entire process cartridge by the cleaning device, which had a life earlier in the past. An image forming apparatus having a process cartridge can be provided.
[Brief description of the drawings]
FIG. 1 is a side view schematically showing a cleaning device to which the present invention is applied and an image forming apparatus having the same.
FIG. 2 is a perspective view of a cleaning device and a member to be cleaned shown in FIG. 1;
FIG. 3 is a perspective view showing a main part of the cleaning device shown in FIG. 2;
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Cleaning device 15 Swinging member 20 Brush roller 100 Image forming device 110 Member to be cleaned G Axial direction of brush roller

Claims (8)

What is claimed is: 1. A cleaning apparatus comprising: a brush roller having a brush abutting on a member to be cleaned, wherein the brush roller swings in an axial direction thereof. 2. The cleaning device according to claim 1, further comprising a swing member that engages with the brush roller and swings the brush roller in the axial direction. 3. The cleaning device according to claim 1, wherein the brush roller rotates following a member to be cleaned. 4. The cleaning device according to claim 1, wherein the length of the brush is 2 mm or less. The cleaning device according to any one of claims 1 to 4, wherein the brush has a fiber thickness of 2 deniers or less and a density of the fibers of 20000 fibers / cm ² or more. . An image forming apparatus comprising the cleaning device according to claim 1. 7. The image forming apparatus according to claim 6, wherein a toner produced by a polymerization method is used. 8. The image forming apparatus according to claim 6, wherein at least the cleaning device forms a process cartridge.

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